Fix #459 - properly support remote SPI with pigpio

Sorry! Dave's messing around with the pin implementations again.
Hopefully the last time. The pin_factory is now really a factory object
which can be asked to produce individual pins or pin-based interfaces
like SPI (which can be supported properly via pigpio).

docs/api_exc.rst

@@ -59,6 +59,20 @@ Errors
 
 .. autoexception:: SPIBadArgs
 
+.. autoexception:: SPIBadChannel
+
+.. autoexception:: SPIFixedClockMode
+
+.. autoexception:: SPIInvalidClockMode
+
+.. autoexception:: SPIFixedBitOrder
+
+.. autoexception:: SPIFixedSelect
+
+.. autoexception:: SPIFixedWordSize
+
+.. autoexception:: SPIInvalidWordSize
+
 .. autoexception:: GPIODeviceError
 
 .. autoexception:: GPIODeviceClosed
@@ -83,23 +97,31 @@ Errors
 
 .. autoexception:: PinInvalidEdges
 
+.. autoexception:: PinInvalidBounce
+
 .. autoexception:: PinSetInput
 
 .. autoexception:: PinFixedPull
 
 .. autoexception:: PinEdgeDetectUnsupported
 
+.. autoexception:: PinGPIOUnsupported
+
+.. autoexception:: PinSPIUnsupported
+
 .. autoexception:: PinPWMError
 
 .. autoexception:: PinPWMUnsupported
 
 .. autoexception:: PinPWMFixedValue
 
+.. autoexception:: PinUnknownPi
+
 .. autoexception:: PinMultiplePins
 
 .. autoexception:: PinNoPins
 
-.. autoexception:: PinUnknownPi
+.. autoexception:: PinInvalidPin
 
 Warnings
 ========
@@ -110,3 +132,7 @@ Warnings
 
 .. autoexception:: SPISoftwareFallback
 
+.. autoexception:: PinFactoryFallback
+
+.. autoexception:: PinNonPhysical
+

docs/api_pins.rst

@@ -11,68 +11,68 @@ are concerned with. However, some users may wish to take advantage of the
 capabilities of alternative GPIO implementations or (in future) use GPIO
 extender chips. This is the purpose of the pins portion of the library.
 
-When you construct a device, you pass in a GPIO pin number. However, what the
+When you construct a device, you pass in a pin specification. However, what the
-library actually expects is a :class:`Pin` implementation. If it finds a simple
+library actually expects is a :class:`Pin` implementation. If it finds anything
-integer number instead, it uses one of the following classes to provide the
+else, it uses the existing ``Device._pin_factory`` to construct a :class:`Pin`
-:class:`Pin` implementation (classes are listed in favoured order):
+implementation based on the specification.
 
-1. :class:`gpiozero.pins.rpigpio.RPiGPIOPin`
+Changing the pin factory
+========================
 
-2. :class:`gpiozero.pins.rpio.RPIOPin`
+The default pin factory can be replaced by specifying a value for the
+``GPIOZERO_PIN_FACTORY`` environment variable. For example:
 
-3. :class:`gpiozero.pins.pigpiod.PiGPIOPin`
+.. code-block:: console
 
-4. :class:`gpiozero.pins.native.NativePin`
+    pi@raspberrypi $ GPIOZERO_PIN_FACTORY=native python
+    Python 3.4.2 (default, Oct 19 2014, 13:31:11)
+    [GCC 4.9.1] on linux
+    Type "help", "copyright", "credits" or "license" for more information.
+    >>> import gpiozero
+    >>> gpiozero.Device._pin_factory
+    <gpiozero.pins.native.NativeFactory object at 0x762c26b0>
 
-You can change the default pin implementation by over-writing the
+The following values, and the corresponding :class:`Factory` and :class:`Pin`
-``pin_factory`` global in the ``devices`` module like so::
+classes are listed in the table below. Factories are listed in the order that
+they are tried by default.
 
-    from gpiozero.pins.native import NativePin
++---------+-----------------------------------------------+-------------------------------------------+
-    import gpiozero.devices
+| Name    | Factory class                                 | Pin class                                 |
-    # Force the default pin implementation to be NativePin
++=========+===============================================+===========================================+
-    gpiozero.devices.pin_factory = NativePin
+| rpigpio | :class:`gpiozero.pins.rpigpio.RPiGPIOFactory` | :class:`gpiozero.pins.rpigpio.RPiGPIOPin` |
++---------+-----------------------------------------------+-------------------------------------------+
+| rpio    | :class:`gpiozero.pins.rpio.RPIOFactory`       | :class:`gpiozero.pins.rpio.RPIOPin`       |
++---------+-----------------------------------------------+-------------------------------------------+
+| pigpio  | :class:`gpiozero.pins.pigpiod.PiGPIOFactory`  | :class:`gpiozero.pins.pigpiod.PiGPIOPin`  |
++---------+-----------------------------------------------+-------------------------------------------+
+| native  | :class:`gpiozero.pins.native.NativeFactory`   | :class:`gpiozero.pins.native.NativePin`   |
++---------+-----------------------------------------------+-------------------------------------------+
+
+If you need to change the default pin factory from within a script, use the
+``Device._set_pin_factory`` class method, passing in the instance of the new
+factory to use. This is only supported at script startup (replacing the factory
+closes all existing pin instances which can have interesting consequences for
+any devices using them)::
+
+    from gpiozero.pins.native import NativeFactory
+    from gpiozero import *
+    Device._set_pin_factory(NativeFactory())
 
     from gpiozero import LED
 
     # This will now use NativePin instead of RPiGPIOPin
     led = LED(16)
 
-``pin_factory`` is a concrete descendent of the abstract :class:`Pin` class.
+Certain factories may take default information from additional sources.
-The descendent may take additional parameters in its constructor provided they
-are optional; GPIO Zero will expect to be able to construct instances with
-nothing more than an integer pin number.
-
-However, the descendent may take default information from additional sources.
 For example, to default to creating pins with
 :class:`gpiozero.pins.pigpiod.PiGPIOPin` on a remote pi called ``remote-pi``
 you can set the :envvar:`PIGPIO_ADDR` environment variable when running your
-script::
+script:
 
-    $ PIGPIO_ADDR=remote-pi python my_script.py
+.. code-block:: console
 
-It is worth noting that instead of passing an integer to device constructors,
+    $ export GPIOZERO_PIN_FACTORY=pigpio
-you can pass an object derived from :class:`Pin` itself::
+    $ PIGPIO_ADDR=remote-pi python3 my_script.py
-
-    from gpiozero.pins.native import NativePin
-    from gpiozero import LED
-
-    led = LED(NativePin(16))
-
-In future, this separation of pins and devices should also permit the library
-to utilize pins that are part of IO extender chips. For example::
-
-    from gpiozero import IOExtender, LED
-
-    ext = IOExtender()
-    led = LED(ext.pins[0])
-    led.on()
-
-.. warning::
-
-    While the devices API is now considered stable and won't change in
-    backwards incompatible ways, the pins API is *not* yet considered stable.
-    It is potentially subject to change in future versions. We welcome any
-    comments from testers!
 
 .. warning::
 
@@ -83,41 +83,48 @@ to utilize pins that are part of IO extender chips. For example::
     actual raspberry pie, you have only yourself to blame.
 
 
-RPiGPIOPin
+RPi.GPIO
-==========
+========
+
+.. autoclass:: gpiozero.pins.rpigpio.RPiGPIOFactory
 
 .. autoclass:: gpiozero.pins.rpigpio.RPiGPIOPin
 
 
-RPIOPin
+RPIO
-=======
+====
+
+.. autoclass:: gpiozero.pins.rpio.RPIOFactory
 
 .. autoclass:: gpiozero.pins.rpio.RPIOPin
 
 
-PiGPIOPin
+PiGPIO
-=========
+======
+
+.. autoclass:: gpiozero.pins.pigpiod.PiGPIOFactory
 
 .. autoclass:: gpiozero.pins.pigpiod.PiGPIOPin
 
 
-NativePin
+Native
-=========
+======
+
+.. autoclass:: gpiozero.pins.native.NativeFactory
 
 .. autoclass:: gpiozero.pins.native.NativePin
 
 
-Abstract Pin
+Base classes
 ============
 
+.. autoclass:: Factory
+    :members:
+
 .. autoclass:: Pin
     :members:
 
-
+.. autoclass:: SPI
-Local Pin
-=========
-
-.. autoclass:: LocalPin
     :members:
 
 

docs/notes.rst

@@ -4,6 +4,7 @@ Notes
 
 .. currentmodule:: gpiozero
 
+
 .. _keep-your-script-running:
 
 Keep your script running
@@ -46,6 +47,7 @@ events to be detected::
     button.when_pressed = hello
     pause()
 
+
 Importing from GPIO Zero
 ========================
 
@@ -70,12 +72,15 @@ In this case, all references to items within GPIO Zero must be prefixed::
 
     button = gpiozero.Button(2)
 
+
 How can I tell what version of gpiozero I have installed?
 =========================================================
 
 The gpiozero library relies on the setuptools package for installation
 services.  You can use the setuptools ``pkg_resources`` API to query which
-version of gpiozero is available in your Python environment like so::
+version of gpiozero is available in your Python environment like so:
+
+.. code-block:: pycon
 
     >>> from pkg_resources import require
     >>> require('gpiozero')
@@ -89,7 +94,9 @@ the first entry in the list will be the version that ``import gpiozero`` will
 import.
 
 If you receive the error "No module named pkg_resources", you need to install
-the ``pip`` utility. This can be done with the following command in Raspbian::
+the ``pip`` utility. This can be done with the following command in Raspbian:
+
+.. code-block:: console
 
     $ sudo apt-get install python-pip
 

docs/recipes.rst

@@ -9,7 +9,7 @@ library. Please note that all recipes are written assuming Python 3. Recipes
 *may* work under Python 2, but no guarantees!
 
 
-.. _pin_numbering:
+.. _pin-numbering:
 
 Pin Numbering
 =============
@@ -429,7 +429,9 @@ functionality without the need to wire up your own LEDs (also useful because
 the power and activity LEDs are "known good").
 
 Firstly you need to disable the usual triggers for the built-in LEDs. This can
-be done from the terminal with the following commands::
+be done from the terminal with the following commands:
+
+.. code-block:: console
 
     $ echo none | sudo tee /sys/class/leds/led0/trigger
     $ echo gpio | sudo tee /sys/class/leds/led1/trigger
@@ -439,7 +441,9 @@ Now you can control the LEDs with gpiozero like so:
 .. literalinclude:: examples/led_builtin.py
 
 To revert the LEDs to their usual purpose you can either reboot your Pi or
-run the following commands::
+run the following commands:
+
+.. code-block:: console
 
     $ echo mmc0 | sudo tee /sys/class/leds/led0/trigger
     $ echo input | sudo tee /sys/class/leds/led1/trigger

gpiozero/__init__.py

@@ -6,8 +6,9 @@ from __future__ import (
 )
 
 from .pins import (
+    Factory,
     Pin,
-    LocalPin,
+    SPI,
 )
 from .pins.data import (
     PiBoardInfo,
@@ -15,47 +16,9 @@ from .pins.data import (
     PinInfo,
     pi_info,
 )
-from .exc import (
+# Yes, import * is naughty, but exc imports nothing else so there's no cross
-    GPIOZeroError,
+# contamination here ... and besides, have you *seen* the list lately?!
-    DeviceClosed,
+from .exc import *
-    BadEventHandler,
-    BadWaitTime,
-    BadQueueLen,
-    CompositeDeviceError,
-    CompositeDeviceBadName,
-    CompositeDeviceBadOrder,
-    CompositeDeviceBadDevice,
-    SPIError,
-    SPIBadArgs,
-    EnergenieSocketMissing,
-    EnergenieBadSocket,
-    GPIODeviceError,
-    GPIODeviceClosed,
-    GPIOPinInUse,
-    GPIOPinMissing,
-    InputDeviceError,
-    OutputDeviceError,
-    OutputDeviceBadValue,
-    PinError,
-    PinInvalidFunction,
-    PinInvalidState,
-    PinInvalidPull,
-    PinInvalidEdges,
-    PinSetInput,
-    PinFixedPull,
-    PinEdgeDetectUnsupported,
-    PinPWMError,
-    PinPWMUnsupported,
-    PinPWMFixedValue,
-    PinUnknownPi,
-    PinMultiplePins,
-    PinNoPins,
-    GPIOZeroWarning,
-    SPIWarning,
-    SPISoftwareFallback,
-    PinWarning,
-    PinNonPhysical,
-)
 from .devices import (
     Device,
     GPIODevice,

gpiozero/devices.py

@@ -10,15 +10,16 @@ str = type('')
 import os
 import atexit
 import weakref
+import warnings
 from collections import namedtuple
 from itertools import chain
 from types import FunctionType
-from threading import RLock
+from threading import Lock
 
 import pkg_resources
 
+from .pins import Pin
 from .threads import _threads_shutdown
-from .pins import _pins_shutdown
 from .mixins import (
     ValuesMixin,
     SharedMixin,
@@ -32,52 +33,11 @@ from .exc import (
     GPIOPinMissing,
     GPIOPinInUse,
     GPIODeviceClosed,
+    PinFactoryFallback,
     )
 from .compat import frozendict
 
 
-def _default_pin_factory(name=os.getenv('GPIOZERO_PIN_FACTORY', None)):
-    group = 'gpiozero_pin_factories'
-    if name is None:
-        # If no factory is explicitly specified, try various names in
-        # "preferred" order. Note that in this case we only select from
-        # gpiozero distribution so without explicitly specifying a name (via
-        # the environment) it's impossible to auto-select a factory from
-        # outside the base distribution
-        #
-        # We prefer RPi.GPIO here as it supports PWM, and all Pi revisions.  If
-        # no third-party libraries are available, however, we fall back to a
-        # pure Python implementation which supports platforms like PyPy
-        dist = pkg_resources.get_distribution('gpiozero')
-        for name in ('RPiGPIOPin', 'RPIOPin', 'PiGPIOPin', 'NativePin'):
-            try:
-                return pkg_resources.load_entry_point(dist, group, name)
-            except ImportError:
-                pass
-        raise BadPinFactory('Unable to locate any default pin factory!')
-    else:
-        for factory in pkg_resources.iter_entry_points(group, name):
-            return factory.load()
-        raise BadPinFactory('Unable to locate pin factory "%s"' % name)
-
-pin_factory = _default_pin_factory()
-
-
-_PINS = set()
-_PINS_LOCK = RLock() # Yes, this needs to be re-entrant
-
-def _shutdown():
-    _threads_shutdown()
-    with _PINS_LOCK:
-        while _PINS:
-            _PINS.pop().close()
-    # Any cleanup routines registered by pins libraries must be called *after*
-    # cleanup of pin objects used by devices
-    _pins_shutdown()
-
-atexit.register(_shutdown)
-
-
 class GPIOMeta(type):
     # NOTE Yes, this is a metaclass. Don't be scared - it's a simple one.
 
@@ -106,7 +66,7 @@ class GPIOMeta(type):
             # already exists. Only construct the instance if the key's new.
             key = cls._shared_key(*args, **kwargs)
             try:
-                self = cls._INSTANCES[key]
+                self = cls._instances[key]
                 self._refs += 1
             except (KeyError, ReferenceError) as e:
                 self = super(GPIOMeta, cls).__call__(*args, **kwargs)
@@ -122,14 +82,14 @@ class GPIOMeta(type):
                             old_close()
                         finally:
                             try:
-                                del cls._INSTANCES[key]
+                                del cls._instances[key]
                             except KeyError:
                                 # If the _refs go negative (too many closes)
                                 # just ignore the resulting KeyError here -
                                 # it's already gone
                                 pass
                 self.close = close
-                cls._INSTANCES[key] = weakref.proxy(self)
+                cls._instances[key] = weakref.proxy(self)
         else:
             # Construct the instance as normal
             self = super(GPIOMeta, cls).__call__(*args, **kwargs)
@@ -229,13 +189,100 @@ class GPIOBase(GPIOMeta(nstr('GPIOBase'), (), {})):
 class Device(ValuesMixin, GPIOBase):
     """
     Represents a single device of any type; GPIO-based, SPI-based, I2C-based,
-    etc. This is the base class of the device hierarchy. It defines the
+    etc. This is the base class of the device hierarchy. It defines the basic
-    basic services applicable to all devices (specifically the :attr:`is_active`
+    services applicable to all devices (specifically the :attr:`is_active`
     property, the :attr:`value` property, and the :meth:`close` method).
     """
+    _pin_factory = None # instance of a Factory sub-class
+    _reservations = {} # maps pin addresses to lists of devices
+    _res_lock = Lock()
+
     def __repr__(self):
         return "<gpiozero.%s object>" % (self.__class__.__name__)
 
+    @classmethod
+    def _set_pin_factory(cls, new_factory):
+        if cls._pin_factory is not None:
+            cls._pin_factory.close()
+        cls._pin_factory = new_factory
+
+    def _reserve_pins(self, *pins_or_addresses):
+        """
+        Called to indicate that the device reserves the right to use the
+        specified *pins_or_addresses*. This should be done during device
+        construction.  If pins are reserved, you must ensure that the
+        reservation is released by eventually called :meth:`_release_pins`.
+
+        The *pins_or_addresses* can be actual :class:`Pin` instances or the
+        addresses of pin instances (each address is a tuple of strings). The
+        latter form is permitted to ensure that devices do not have to
+        construct :class:`Pin` objects to reserve pins. This is important as
+        constructing a pin often configures it (e.g. as an input) which
+        conflicts with alternate pin functions like SPI.
+        """
+        addresses = (
+            p.address if isinstance(p, Pin) else p
+            for p in pins_or_addresses
+            )
+        with self._res_lock:
+            for address in addresses:
+                try:
+                    conflictors = self._reservations[address]
+                except KeyError:
+                    conflictors = []
+                    self._reservations[address] = conflictors
+                for device_ref in conflictors:
+                    device = device_ref()
+                    if device is not None and self._conflicts_with(device):
+                        raise GPIOPinInUse(
+                            'pin %s is already in use by %r' % (
+                                '/'.join(address), device)
+                        )
+                conflictors.append(weakref.ref(self))
+
+    def _release_pins(self, *pins_or_addresses):
+        """
+        Releases the reservation of this device against *pins_or_addresses*.
+        This is typically called during :meth:`close` to clean up reservations
+        taken during construction. Releasing a reservation that is not
+        currently held will be silently ignored (to permit clean-up after
+        failed / partial construction).
+        """
+        addresses = (
+            p.address if isinstance(p, Pin) else p
+            for p in pins_or_addresses
+            )
+        with self._res_lock:
+            for address in addresses:
+                self._reservations[address] = [
+                    ref for ref in self._reservations[address]
+                    if ref() not in (self, None) # may as well clean up dead refs
+                    ]
+
+    def _release_all(self):
+        """
+        Releases all pin reservations taken out by this device. See
+        :meth:`_release_pins` for further information).
+        """
+        with self._res_lock:
+            Device._reservations = {
+                address: [
+                    ref for ref in conflictors
+                    if ref() not in (self, None)
+                    ]
+                for address, conflictors in self._reservations.items()
+                }
+
+    def _conflicts_with(self, other):
+        """
+        Called by :meth:`_reserve_pin` to test whether the *other*
+        :class:`Device` using a common pin conflicts with this device's intent
+        to use it. The default is ``True`` indicating that all devices conflict
+        with common pins.  Sub-classes may override this to permit more nuanced
+        replies.
+        """
+        return True
+
     @property
     def value(self):
         """
@@ -378,14 +425,12 @@ class GPIODevice(Device):
         self._pin = None
         if pin is None:
             raise GPIOPinMissing('No pin given')
-        if isinstance(pin, int):
+        if isinstance(pin, Pin):
-            pin = pin_factory(pin)
+            self._reserve_pins(pin)
-        with _PINS_LOCK:
+        else:
-            if pin in _PINS:
+            # Check you can reserve *before* constructing the pin
-                raise GPIOPinInUse(
+            self._reserve_pins(self._pin_factory.pin_address(pin))
-                    'pin %r is already in use by another gpiozero object' % pin
+            pin = self._pin_factory.pin(pin)
-                )
-            _PINS.add(pin)
         self._pin = pin
         self._active_state = True
         self._inactive_state = False
@@ -402,12 +447,10 @@ class GPIODevice(Device):
 
     def close(self):
         super(GPIODevice, self).close()
-        with _PINS_LOCK:
+        if self._pin is not None:
-            pin = self._pin
+            self._release_pins(self._pin)
+            self._pin.close()
             self._pin = None
-            if pin in _PINS:
-                _PINS.remove(pin)
-                pin.close()
 
     @property
     def closed(self):
@@ -441,3 +484,41 @@ class GPIODevice(Device):
         except DeviceClosed:
             return "<gpiozero.%s object closed>" % self.__class__.__name__
 
+
+# Defined last to ensure Device is defined before attempting to load any pin
+# factory; pin factories want to load spi which in turn relies on devices (for
+# the soft-SPI implementation)
+def _default_pin_factory(name=os.getenv('GPIOZERO_PIN_FACTORY', None)):
+    group = 'gpiozero_pin_factories'
+    if name is None:
+        # If no factory is explicitly specified, try various names in
+        # "preferred" order. Note that in this case we only select from
+        # gpiozero distribution so without explicitly specifying a name (via
+        # the environment) it's impossible to auto-select a factory from
+        # outside the base distribution
+        #
+        # We prefer RPi.GPIO here as it supports PWM, and all Pi revisions. If
+        # no third-party libraries are available, however, we fall back to a
+        # pure Python implementation which supports platforms like PyPy
+        dist = pkg_resources.get_distribution('gpiozero')
+        for name in ('rpigpio', 'rpio', 'pigpio', 'native'):
+            try:
+                return pkg_resources.load_entry_point(dist, group, name)()
+            except Exception as e:
+                warnings.warn(
+                    PinFactoryFallback(
+                        'Failed to load factory %s: %s' % (name, str(e))))
+        raise BadPinFactory('Unable to load any default pin factory!')
+    else:
+        for factory in pkg_resources.iter_entry_points(group, name.lower()):
+            return factory.load()()
+        raise BadPinFactory('Unable to find pin factory "%s"' % name)
+
+Device._set_pin_factory(_default_pin_factory())
+
+def _shutdown():
+    _threads_shutdown()
+    Device._set_pin_factory(None)
+
+atexit.register(_shutdown)
+

gpiozero/exc.py

@@ -52,6 +52,24 @@ class SPIBadArgs(SPIError, ValueError):
 class SPIBadChannel(SPIError, ValueError):
     "Error raised when an invalid channel is given to an :class:`AnalogInputDevice`"
 
+class SPIFixedClockMode(SPIError, AttributeError):
+    "Error raised when the SPI clock mode cannot be changed"
+
+class SPIInvalidClockMode(SPIError, ValueError):
+    "Error raised when an invalid clock mode is given to an SPI implementation"
+
+class SPIFixedBitOrder(SPIError, AttributeError):
+    "Error raised when the SPI bit-endianness cannot be changed"
+
+class SPIFixedSelect(SPIError, AttributeError):
+    "Error raised when the SPI select polarity cannot be changed"
+
+class SPIFixedWordSize(SPIError, AttributeError):
+    "Error raised when the number of bits per word cannot be changed"
+
+class SPIInvalidWordSize(SPIError, ValueError):
+    "Error raised when an invalid (out of range) number of bits per word is specified"
+
 class GPIODeviceError(GPIOZeroError):
     "Base class for errors specific to the GPIODevice hierarchy"
 
@@ -62,7 +80,7 @@ class GPIOPinInUse(GPIODeviceError):
     "Error raised when attempting to use a pin already in use by another device"
 
 class GPIOPinMissing(GPIODeviceError, ValueError):
-    "Error raised when a pin number is not specified"
+    "Error raised when a pin specification is not given"
 
 class InputDeviceError(GPIODeviceError):
     "Base class for errors specific to the InputDevice hierarchy"
@@ -100,6 +118,12 @@ class PinFixedPull(PinError, AttributeError):
 class PinEdgeDetectUnsupported(PinError, AttributeError):
     "Error raised when attempting to use edge detection on unsupported pins"
 
+class PinGPIOUnsupported(PinError, NotImplementedError):
+    "Error raised when attempting to obtain a GPIO interface on unsupported pins"
+
+class PinSPIUnsupported(PinError, NotImplementedError):
+    "Error raised when attempting to obtain an SPI interface on unsupported pins"
+
 class PinPWMError(PinError):
     "Base class for errors related to PWM implementations"
 
@@ -118,6 +142,9 @@ class PinMultiplePins(PinError, RuntimeError):
 class PinNoPins(PinError, RuntimeError):
     "Error raised when no pins support the requested function"
 
+class PinInvalidPin(PinError, ValueError):
+    "Error raised when an invalid pin specification is provided"
+
 class GPIOZeroWarning(Warning):
     "Base class for all warnings in GPIO Zero"
 
@@ -130,6 +157,9 @@ class SPISoftwareFallback(SPIWarning):
 class PinWarning(GPIOZeroWarning):
     "Base class for warnings related to pin implementations"
 
+class PinFactoryFallback(PinWarning):
+    "Warning raised when a default pin factory fails to load and a fallback is tried"
+
 class PinNonPhysical(PinWarning):
     "Warning raised when a non-physical pin is specified in a constructor"
 

gpiozero/input_devices.py

@@ -165,7 +165,7 @@ class SmoothedInputDevice(EventsMixin, InputDevice):
             if self.partial or self._queue.full.is_set():
                 return super(SmoothedInputDevice, self).__repr__()
             else:
-                return "<gpiozero.%s object on pin=%r, pull_up=%s>" % (
+                return "<gpiozero.%s object on pin %r, pull_up=%s>" % (
                     self.__class__.__name__, self.pin, self.pull_up)
 
     @property
@@ -240,7 +240,7 @@ class Button(HoldMixin, DigitalInputDevice):
         print("The button was pressed!")
 
     :param int pin:
-        The GPIO pin which the button is attached to. See :ref:`pin_numbering`
+        The GPIO pin which the button is attached to. See :ref:`pin-numbering`
         for valid pin numbers.
 
     :param bool pull_up:
@@ -302,7 +302,7 @@ class LineSensor(SmoothedInputDevice):
         pause()
 
     :param int pin:
-        The GPIO pin which the sensor is attached to. See :ref:`pin_numbering`
+        The GPIO pin which the sensor is attached to. See :ref:`pin-numbering`
         for valid pin numbers.
 
     :param int queue_len:
@@ -371,7 +371,7 @@ class MotionSensor(SmoothedInputDevice):
         print("Motion detected!")
 
     :param int pin:
-        The GPIO pin which the sensor is attached to. See :ref:`pin_numbering`
+        The GPIO pin which the sensor is attached to. See :ref:`pin-numbering`
         for valid pin numbers.
 
     :param int queue_len:
@@ -435,7 +435,7 @@ class LightSensor(SmoothedInputDevice):
         print("Light detected!")
 
     :param int pin:
-        The GPIO pin which the sensor is attached to. See :ref:`pin_numbering`
+        The GPIO pin which the sensor is attached to. See :ref:`pin-numbering`
         for valid pin numbers.
 
     :param int queue_len:
@@ -543,11 +543,11 @@ class DistanceSensor(SmoothedInputDevice):
 
     :param int echo:
         The GPIO pin which the ECHO pin is attached to. See
-        :ref:`pin_numbering` for valid pin numbers.
+        :ref:`pin-numbering` for valid pin numbers.
 
     :param int trigger:
         The GPIO pin which the TRIG pin is attached to. See
-        :ref:`pin_numbering` for valid pin numbers.
+        :ref:`pin-numbering` for valid pin numbers.
 
     :param int queue_len:
         The length of the queue used to store values read from the sensor.

gpiozero/mixins.py

@@ -127,7 +127,7 @@ class SharedMixin(object):
     When :meth:`close` is called, an internal reference counter will be
     decremented and the instance will only close when it reaches zero.
     """
-    _INSTANCES = {}
+    _instances = {}
 
     def __del__(self):
         self._refs = 0

gpiozero/output_devices.py

@@ -128,8 +128,8 @@ class DigitalOutputDevice(OutputDevice):
     """
     def __init__(self, pin=None, active_high=True, initial_value=False):
         self._blink_thread = None
-        super(DigitalOutputDevice, self).__init__(pin, active_high, initial_value)
         self._controller = None
+        super(DigitalOutputDevice, self).__init__(pin, active_high, initial_value)
 
     @property
     def value(self):
@@ -217,7 +217,7 @@ class LED(DigitalOutputDevice):
         led.on()
 
     :param int pin:
-        The GPIO pin which the LED is attached to. See :ref:`pin_numbering` for
+        The GPIO pin which the LED is attached to. See :ref:`pin-numbering` for
         valid pin numbers.
 
     :param bool active_high:
@@ -252,7 +252,7 @@ class Buzzer(DigitalOutputDevice):
         bz.on()
 
     :param int pin:
-        The GPIO pin which the buzzer is attached to. See :ref:`pin_numbering`
+        The GPIO pin which the buzzer is attached to. See :ref:`pin-numbering`
         for valid pin numbers.
 
     :param bool active_high:
@@ -276,7 +276,7 @@ class PWMOutputDevice(OutputDevice):
     Generic output device configured for pulse-width modulation (PWM).
 
     :param int pin:
-        The GPIO pin which the device is attached to. See :ref:`pin_numbering`
+        The GPIO pin which the device is attached to. See :ref:`pin-numbering`
         for valid pin numbers.
 
     :param bool active_high:
@@ -483,7 +483,7 @@ class PWMLED(PWMOutputDevice):
     an optional resistor to prevent the LED from burning out.
 
     :param int pin:
-        The GPIO pin which the LED is attached to. See :ref:`pin_numbering` for
+        The GPIO pin which the LED is attached to. See :ref:`pin-numbering` for
         valid pin numbers.
 
     :param bool active_high:
@@ -562,8 +562,12 @@ class RGBLED(SourceMixin, Device):
             raise GPIOPinMissing('red, green, and blue pins must be provided')
         LEDClass = PWMLED if pwm else LED
         super(RGBLED, self).__init__()
-        self._leds = tuple(LEDClass(pin, active_high) for pin in (red, green, blue))
+        try:
-        self.value = initial_value
+            self._leds = tuple(LEDClass(pin, active_high) for pin in (red, green, blue))
+            self.value = initial_value
+        except:
+            self.close()
+            raise
 
     red = _led_property(0)
     green = _led_property(1)
@@ -926,7 +930,7 @@ class Servo(SourceMixin, CompositeDevice):
             sleep(1)
 
     :param int pin:
-        The GPIO pin which the device is attached to. See :ref:`pin_numbering`
+        The GPIO pin which the device is attached to. See :ref:`pin-numbering`
         for valid pin numbers.
 
     :param float initial_value:
@@ -1116,7 +1120,7 @@ class AngularServo(Servo):
         expectations of minimum and maximum.
 
     :param int pin:
-        The GPIO pin which the device is attached to. See :ref:`pin_numbering`
+        The GPIO pin which the device is attached to. See :ref:`pin-numbering`
         for valid pin numbers.
 
     :param float initial_angle:

gpiozero/pins/__init__.py

@@ -1,3 +1,5 @@
+# vim: set fileencoding=utf-8:
+
 from __future__ import (
     unicode_literals,
     absolute_import,
@@ -6,32 +8,124 @@ from __future__ import (
     )
 str = type('')
 
-import io
-
-from .data import pi_info
 from ..exc import (
     PinInvalidFunction,
     PinSetInput,
     PinFixedPull,
+    PinSPIUnsupported,
     PinPWMUnsupported,
     PinEdgeDetectUnsupported,
+    SPIFixedClockMode,
+    SPIFixedBitOrder,
+    SPIFixedSelect,
+    SPIFixedWordSize,
     )
 
 
-PINS_CLEANUP = []
+class Factory(object):
-def _pins_shutdown():
+    """
-    for routine in PINS_CLEANUP:
+    Generates pins, SPI, and I2C interfaces for devices. This is an abstract
-        routine()
+    base class for pin factories. Descendents must override:
+
+    * :meth:`_get_address`
+    * :meth:`pin_address`
+
+    Descendents may override:
+
+    * :meth:`close`
+    * :meth:`pin`
+    * :meth:`spi`
+    * :meth:`_get_pi_info`
+    """
+
+    def close(self):
+        """
+        Closes the pin factory. This is expected to clean up all resources
+        manipulated by the factory. It it typically called at script
+        termination.
+        """
+        pass
+
+    def pin(self, spec):
+        """
+        Creates an instance of a :class:`Pin` descendent representing the
+        specified pin.
+
+        .. warning::
+
+            Descendents must ensure that pin instances representing the same
+            hardware are identical; i.e. two separate invocations of
+            :meth:`pin` for the same pin specification must return the same
+            object.
+        """
+        raise PinGPIOUnsupported("GPIO not supported by this pin factory")
+
+    def pin_address(self, spec):
+        """
+        Returns the address that a pin *would* have if constructed from the
+        given *spec*.
+
+        This unusual method is used by the pin reservation system to check
+        for conflicts *prior* to pin construction; with most implementations,
+        pin construction implicitly alters the state of the pin (e.g. setting
+        it to an input). This allows pin reservation to take place without
+        affecting the state of other components.
+        """
+        raise NotImplementedError
+
+    def spi(self, **spi_args):
+        """
+        Returns an instance of an :class:`SPI` interface, for the specified SPI
+        *port* and *device*, or for the specified pins (*clock_pin*,
+        *mosi_pin*, *miso_pin*, and *select_pin*).  Only one of the schemes can
+        be used; attempting to mix *port* and *device* with pin numbers will
+        raise :exc:`SPIBadArgs`.
+        """
+        raise PinSPIUnsupported('SPI not supported by this pin factory')
+
+    def _get_address(self):
+        raise NotImplementedError
+
+    address = property(
+        lambda self: self._get_address(),
+        doc="""\
+        Returns a tuple of strings representing the address of the factory.
+        For the Pi itself this is a tuple of one string representing the Pi's
+        address (e.g. "localhost"). Expander chips can return a tuple appending
+        whatever string they require to uniquely identify the expander chip
+        amongst all factories in the system.
+
+        .. note::
+
+            This property *must* return an immutable object capable of being
+            used as a dictionary key.
+        """)
+
+    def _get_pi_info(self):
+        return None
+
+    pi_info = property(
+        lambda self: self._get_pi_info(),
+        doc="""\
+        Returns a :class:`PiBoardInfo` instance representing the Pi that
+        instances generated by this factory will be attached to.
+
+        If the pins represented by this class are not *directly* attached to a
+        Pi (e.g. the pin is attached to a board attached to the Pi, or the pins
+        are not on a Pi at all), this may return ``None``.
+        """)
 
 
 class Pin(object):
     """
-    Abstract base class representing a GPIO pin or a pin from an IO extender.
+    Abstract base class representing a pin attached to some form of controller,
+    be it GPIO, SPI, ADC, etc.
 
     Descendents should override property getters and setters to accurately
     represent the capabilities of pins. The following functions *must* be
     overridden:
 
+    * :meth:`_get_address`
     * :meth:`_get_function`
     * :meth:`_set_function`
     * :meth:`_get_state`
@@ -39,6 +133,8 @@ class Pin(object):
     The following functions *may* be overridden if applicable:
 
     * :meth:`close`
+    * :meth:`output_with_state`
+    * :meth:`input_with_pull`
     * :meth:`_set_state`
     * :meth:`_get_frequency`
     * :meth:`_set_frequency`
@@ -50,20 +146,10 @@ class Pin(object):
     * :meth:`_set_edges`
     * :meth:`_get_when_changed`
     * :meth:`_set_when_changed`
-    * :meth:`pi_info`
-    * :meth:`output_with_state`
-    * :meth:`input_with_pull`
-
-    .. warning::
-
-        Descendents must ensure that pin instances representing the same
-        physical hardware are identical, right down to object identity. The
-        framework relies on this to correctly clean up resources at interpreter
-        shutdown.
     """
 
     def __repr__(self):
-        return "Abstract pin"
+        return self.address[-1]
 
     def close(self):
         """
@@ -105,6 +191,18 @@ class Pin(object):
         self.function = 'input'
         self.pull = pull
 
+    def _get_address(self):
+        raise NotImplementedError
+
+    address = property(
+        lambda self: self._get_address(),
+        doc="""\
+        The address of the pin. This property is a tuple of strings constructed
+        from the owning factory's address with the unique address of the pin
+        appended to it. The tuple as a whole uniquely identifies the pin
+        amongst all pins attached to the system.
+        """)
+
     def _get_function(self):
         return "input"
 
@@ -140,10 +238,19 @@ class Pin(object):
         doc="""\
         The state of the pin. This is 0 for low, and 1 for high. As a low level
         view of the pin, no swapping is performed in the case of pull ups (see
-        :attr:`pull` for more information).
+        :attr:`pull` for more information):
 
-        If PWM is currently active (when :attr:`frequency` is not ``None``),
+        .. code-block:: text
-        this represents the PWM duty cycle as a value between 0.0 and 1.0.
+
+            HIGH - - - - >       ,----------------------
+                                 |
+                                 |
+            LOW  ----------------'
+
+        Descendents which implement analog, or analog-like capabilities can
+        return values between 0 and 1. For example, pins implementing PWM
+        (where :attr:`frequency` is not ``None``) return a value between 0.0
+        and 1.0 representing the current PWM duty cycle.
 
         If a pin is currently configured for input, and an attempt is made to
         set this attribute, :exc:`PinSetInput` will be raised. If an invalid
@@ -205,6 +312,26 @@ class Pin(object):
         detection, measured in seconds. If bounce detection is not currently in
         use, this is ``None``.
 
+        For example, if :attr:`edge` is currently "rising", :attr:`bounce` is
+        currently 5/1000 (5ms), then the waveform below will only fire
+        :attr:`when_changed` on two occasions despite there being three rising
+        edges:
+
+        .. code-block:: text
+
+            TIME 0...1...2...3...4...5...6...7...8...9...10..11..12 ms
+
+            bounce elimination   |===================| |==============
+
+            HIGH - - - - >       ,--. ,--------------. ,--.
+                                 |  | |              | |  |
+                                 |  | |              | |  |
+            LOW  ----------------'  `-'              `-'  `-----------
+                                 :                     :
+                                 :                     :
+                           when_changed          when_changed
+                               fires                 fires
+
         If the pin does not support edge detection, attempts to set this
         property will raise :exc:`PinEdgeDetectUnsupported`. If the pin
         supports edge detection, the class must implement bounce detection,
@@ -223,7 +350,18 @@ class Pin(object):
         doc="""\
         The edge that will trigger execution of the function or bound method
         assigned to :attr:`when_changed`. This can be one of the strings
-        "both" (the default), "rising", "falling", or "none".
+        "both" (the default), "rising", "falling", or "none":
+
+        .. code-block:: text
+
+            HIGH - - - - >           ,--------------.
+                                     |              |
+                                     |              |
+            LOW  --------------------'              `--------------
+                                     :              :
+                                     :              :
+            Fires when_changed     "both"         "both"
+            when edges is ...     "rising"       "falling"
 
         If the pin does not support edge detection, attempts to set this
         property will raise :exc:`PinEdgeDetectUnsupported`.
@@ -247,48 +385,300 @@ class Pin(object):
         property will raise :exc:`PinEdgeDetectUnsupported`.
         """)
 
-    @classmethod
-    def pi_info(cls):
-        """
-        Returns a :class:`PiBoardInfo` instance representing the Pi that
-        instances of this pin class will be attached to.
 
-        If the pins represented by this class are not *directly* attached to a
+class SPI(object):
-        Pi (e.g. the pin is attached to a board attached to the Pi, or the pins
-        are not on a Pi at all), this may return ``None``.
-        """
-        return None
-
-
-class LocalPin(Pin):
     """
-    Abstract base class representing pins attached locally to a Pi. This forms
+    Abstract interface for `Serial Peripheral Interface`_ (SPI) implementations.
-    the base class for local-only pin interfaces (:class:`RPiGPIOPin`,
+    Descendents *must* override the following:
-    :class:`RPIOPin`, and :class:`NativePin`).
+
+    * :meth:`transfer`
+    * :meth:`_get_clock_mode`
+
+    Descendents *may* override the following methods:
+
+    * :meth:`read`
+    * :meth:`write`
+    * :meth:`_set_clock_mode`
+    * :meth:`_get_lsb_first`
+    * :meth:`_set_lsb_first`
+    * :meth:`_get_select_high`
+    * :meth:`_set_select_high`
+    * :meth:`_get_bits_per_word`
+    * :meth:`_set_bits_per_word`
+
+    .. _Serial Peripheral Interface: https://en.wikipedia.org/wiki/Serial_Peripheral_Interface_Bus
     """
-    _PI_REVISION = None
 
-    @classmethod
+    def read(self, n):
-    def pi_info(cls):
         """
-        Returns a :class:`PiBoardInfo` instance representing the local Pi.
+        Read *n* words of data from the SPI interface, returning them as a
-        The Pi's revision is determined by reading :file:`/proc/cpuinfo`. If
+        sequence of unsigned ints, each no larger than the configured
-        no valid revision is found, returns ``None``.
+        :attr:`bits_per_word` of the interface.
-        """
+
-        # Cache the result as we can reasonably assume it won't change during
+        This method is typically used with read-only devices that feature
-        # runtime (this is LocalPin after all; descendents that deal with
+        half-duplex communication. See :meth:`transfer` for full duplex
-        # remote Pis should inherit from Pin instead)
+        communication.
-        if cls._PI_REVISION is None:
+        """
-            with io.open('/proc/cpuinfo', 'r') as f:
+        return self.transfer((0,) * n)
-                for line in f:
+
-                    if line.startswith('Revision'):
+    def write(self, data):
-                        revision = line.split(':')[1].strip().lower()
+        """
-                        overvolted = revision.startswith('100')
+        Write *data* to the SPI interface. *data* must be a sequence of
-                        if overvolted:
+        unsigned integer words each of which will fit within the configured
-                            revision = revision[-4:]
+        :attr:`bits_per_word` of the interface. The method returns the number
-                        cls._PI_REVISION = revision
+        of words written to the interface (which may be less than or equal to
-                        break
+        the length of *data*).
-                if cls._PI_REVISION is None:
+
-                    return None # something weird going on
+        This method is typically used with write-only devices that feature
-        return pi_info(cls._PI_REVISION)
+        half-duplex communication. See :meth:`transfer` for full duplex
+        communication.
+        """
+        return len(self.transfer(data))
+
+    def transfer(self, data):
+        """
+        Write *data* to the SPI interface. *data* must be a sequence of
+        unsigned integer words each of which will fit within the configured
+        :attr:`bits_per_word` of the interface. The method returns the sequence
+        of words read from the interface while writing occurred (full duplex
+        communication).
+
+        The length of the sequence returned dictates the number of words of
+        *data* written to the interface. Each word in the returned sequence
+        will be an unsigned integer no larger than the configured
+        :attr:`bits_per_word` of the interface.
+        """
+        raise NotImplementedError
+
+    @property
+    def clock_polarity(self):
+        """
+        The polarity of the SPI clock pin. If this is ``False`` (the default),
+        the clock pin will idle low, and pulse high. Setting this to ``True``
+        will cause the clock pin to idle high, and pulse low. On many data
+        sheets this is documented as the CPOL value.
+
+        The following diagram illustrates the waveform when
+        :attr:`clock_polarity` is ``False`` (the default), equivalent to CPOL
+        0:
+
+        .. code-block:: text
+
+                   on      on      on      on      on      on      on
+                  ,---.   ,---.   ,---.   ,---.   ,---.   ,---.   ,---.
+            CLK   |   |   |   |   |   |   |   |   |   |   |   |   |   |
+                  |   |   |   |   |   |   |   |   |   |   |   |   |   |
+            ------'   `---'   `---'   `---'   `---'   `---'   `---'   `------
+            idle       off     off     off     off     off     off       idle
+
+        The following diagram illustrates the waveform when
+        :attr:`clock_polarity` is ``True``, equivalent to CPOL 1:
+
+        .. code-block:: text
+
+            idle       off     off     off     off     off     off       idle
+            ------.   ,---.   ,---.   ,---.   ,---.   ,---.   ,---.   ,------
+                  |   |   |   |   |   |   |   |   |   |   |   |   |   |
+            CLK   |   |   |   |   |   |   |   |   |   |   |   |   |   |
+                  `---'   `---'   `---'   `---'   `---'   `---'   `---'
+                   on      on      on      on      on      on      on
+        """
+        return bool(self.clock_mode & 2)
+
+    @clock_polarity.setter
+    def clock_polarity(self, value):
+        self.clock_mode = self.clock_mode & (~2) | (bool(value) << 1)
+
+    @property
+    def clock_phase(self):
+        """
+        The phase of the SPI clock pin. If this is ``False`` (the default),
+        data will be read from the MISO pin when the clock pin activates.
+        Setting this to ``True`` will cause data to be read from the MISO pin
+        when the clock pin deactivates. On many data sheets this is documented
+        as the CPHA value. Whether the clock edge is rising or falling when the
+        clock is considered activated is controlled by the
+        :attr:`clock_polarity` attribute (corresponding to CPOL).
+
+        The following diagram indicates when data is read when
+        :attr:`clock_polarity` is ``False``, and :attr:`clock_phase` is
+        ``False`` (the default), equivalent to CPHA 0:
+
+        .. code-block:: text
+
+                ,---.   ,---.   ,---.   ,---.   ,---.   ,---.   ,---.
+            CLK |   |   |   |   |   |   |   |   |   |   |   |   |   |
+                |   |   |   |   |   |   |   |   |   |   |   |   |   |
+            ----'   `---'   `---'   `---'   `---'   `---'   `---'   `-------
+                :       :       :       :       :       :       :
+            MISO---.   ,---.   ,---.   ,---.   ,---.   ,---.   ,---.
+              /     \ /     \ /     \ /     \ /     \ /     \ /     \\
+            -{  Bit  X  Bit  X  Bit  X  Bit  X  Bit  X  Bit  X  Bit  }------
+              \     / \     / \     / \     / \     / \     / \     /
+               `---'   `---'   `---'   `---'   `---'   `---'   `---'
+
+        The following diagram indicates when data is read when
+        :attr:`clock_polarity` is ``False``, but :attr:`clock_phase` is
+        ``True``, equivalent to CPHA 1:
+
+        .. code-block:: text
+
+                ,---.   ,---.   ,---.   ,---.   ,---.   ,---.   ,---.
+            CLK |   |   |   |   |   |   |   |   |   |   |   |   |   |
+                |   |   |   |   |   |   |   |   |   |   |   |   |   |
+            ----'   `---'   `---'   `---'   `---'   `---'   `---'   `-------
+                    :       :       :       :       :       :       :
+            MISO   ,---.   ,---.   ,---.   ,---.   ,---.   ,---.   ,---.
+                  /     \ /     \ /     \ /     \ /     \ /     \ /     \\
+            -----{  Bit  X  Bit  X  Bit  X  Bit  X  Bit  X  Bit  X  Bit  }--
+                  \     / \     / \     / \     / \     / \     / \     /
+                   `---'   `---'   `---'   `---'   `---'   `---'   `---'
+        """
+        return bool(self.clock_mode & 1)
+
+    @clock_phase.setter
+    def clock_phase(self, value):
+        self.clock_mode = self.clock_mode & (~1) | bool(value)
+
+    def _get_clock_mode(self):
+        raise NotImplementedError
+
+    def _set_clock_mode(self, value):
+        raise SPIFixedClockMode("clock_mode cannot be changed on %r" % self)
+
+    clock_mode = property(
+        lambda self: self._get_clock_mode(),
+        lambda self, value: self._set_clock_mode(value),
+        doc="""\
+        Presents a value representing the :attr:`clock_polarity` and
+        :attr:`clock_phase` attributes combined according to the following
+        table:
+
+        +------+-----------------+--------------+
+        | mode | polarity (CPOL) | phase (CPHA) |
+        +======+=================+==============+
+        | 0    | False           | False        |
+        | 1    | False           | True         |
+        | 2    | True            | False        |
+        | 3    | True            | True         |
+        +------+-----------------+--------------+
+
+        Adjusting this value adjusts both the :attr:`clock_polarity` and
+        :attr:`clock_phase` attributes simultaneously.
+        """)
+
+    def _get_lsb_first(self):
+        return False
+
+    def _set_lsb_first(self, value):
+        raise SPIFixedBitOrder("lsb_first cannot be changed on %r" % self)
+
+    lsb_first = property(
+        lambda self: self._get_lsb_first(),
+        lambda self, value: self._set_lsb_first(value),
+        doc="""\
+        Controls whether words are read and written LSB in (Least Significant
+        Bit first) order. The default is ``False`` indicating that words are
+        read and written in MSB (Most Significant Bit first) order.
+        Effectively, this controls the `Bit endianness`_ of the connection.
+
+        The following diagram shows the a word containing the number 5 (binary
+        0101) transmitted on MISO with :attr:`bits_per_word` set to 4, and
+        :attr:`clock_mode` set to 0, when :attr:`lsb_first` is ``False`` (the
+        default):
+
+        .. code-block:: text
+
+                ,---.   ,---.   ,---.   ,---.
+            CLK |   |   |   |   |   |   |   |
+                |   |   |   |   |   |   |   |
+            ----'   `---'   `---'   `---'   `-----
+                :     ,-------. :     ,-------.
+            MISO:     | :     | :     | :     |
+                :     | :     | :     | :     |
+            ----------' :     `-------' :     `----
+                :       :       :       :
+               MSB                     LSB
+
+        And now with :attr:`lsb_first` set to ``True`` (and all other
+        parameters the same):
+
+        .. code-block:: text
+
+                ,---.   ,---.   ,---.   ,---.
+            CLK |   |   |   |   |   |   |   |
+                |   |   |   |   |   |   |   |
+            ----'   `---'   `---'   `---'   `-----
+              ,-------. :     ,-------. :
+            MISO:     | :     | :     | :
+              | :     | :     | :     | :
+            --' :     `-------' :     `-----------
+                :       :       :       :
+               LSB                     MSB
+
+        .. _Bit endianness: https://en.wikipedia.org/wiki/Endianness#Bit_endianness
+        """)
+
+    def _get_select_high(self):
+        return False
+
+    def _set_select_high(self, value):
+        raise SPIFixedSelect("select_high cannot be changed on %r" % self)
+
+    select_high = property(
+        lambda self: self._get_select_high(),
+        lambda self, value: self._set_select_high(value),
+        doc="""\
+        If ``False`` (the default), the chip select line is considered active
+        when it is pulled low. When set to ``True``, the chip select line is
+        considered active when it is driven high.
+
+        The following diagram shows the waveform of the chip select line, and
+        the clock when :attr:`clock_polarity` is ``False``, and
+        :attr:`select_high` is ``False`` (the default):
+
+        .. code-block:: text
+
+            ---.                                                     ,------
+            __ |                                                     |
+            CS |      chip is selected, and will react to clock      |  idle
+               `-----------------------------------------------------'
+
+                ,---.   ,---.   ,---.   ,---.   ,---.   ,---.   ,---.
+            CLK |   |   |   |   |   |   |   |   |   |   |   |   |   |
+                |   |   |   |   |   |   |   |   |   |   |   |   |   |
+            ----'   `---'   `---'   `---'   `---'   `---'   `---'   `-------
+
+        And when :attr:`select_high` is ``True``:
+
+        .. code-block:: text
+
+               ,-----------------------------------------------------.
+            CS |      chip is selected, and will react to clock      |  idle
+               |                                                     |
+            ---'                                                     `------
+
+                ,---.   ,---.   ,---.   ,---.   ,---.   ,---.   ,---.
+            CLK |   |   |   |   |   |   |   |   |   |   |   |   |   |
+                |   |   |   |   |   |   |   |   |   |   |   |   |   |
+            ----'   `---'   `---'   `---'   `---'   `---'   `---'   `-------
+        """)
+
+    def _get_bits_per_word(self):
+        return 8
+
+    def _set_bits_per_word(self, value):
+        raise SPIFixedWordSize("bits_per_word cannot be changed on %r" % self)
+
+    bits_per_word = property(
+        lambda self: self._get_bits_per_word(),
+        lambda self, value: self._set_bits_per_word(value),
+        doc="""\
+        Controls the number of bits that make up a word, and thus where the
+        word boundaries appear in the data stream, and the maximum value of a
+        word. Defaults to 8 meaning that words are effectively bytes.
+
+        Several implementations do not support non-byte-sized words.
+        """)
+
 

gpiozero/pins/data.py

@@ -13,7 +13,7 @@ from itertools import cycle
 from operator import attrgetter
 from collections import namedtuple
 
-from ..exc import PinUnknownPi, PinMultiplePins, PinNoPins
+from ..exc import PinUnknownPi, PinMultiplePins, PinNoPins, PinInvalidPin
 
 
 # Some useful constants for describing pins
@@ -119,8 +119,8 @@ A_BOARD = """\
 
 BPLUS_BOARD = """\
 {style:white on green},--------------------------------.{style:reset}
-{style:white on green}| {P1:{style} col2}{style:white on green} P1     {style:black on white}+===={style:reset}
+{style:white on green}| {J8:{style} col2}{style:white on green} J8     {style:black on white}+===={style:reset}
-{style:white on green}| {P1:{style} col1}{style:white on green}        {style:black on white}| USB{style:reset}
+{style:white on green}| {J8:{style} col1}{style:white on green}        {style:black on white}| USB{style:reset}
 {style:white on green}|                             {style:black on white}+===={style:reset}
 {style:white on green}|      {style:bold}Pi Model {model:2s} V{pcb_revision:3s}{style:normal}          |{style:reset}
 {style:white on green}|      {style:on black}+----+{style:on green}                 {style:black on white}+===={style:reset}
@@ -134,8 +134,8 @@ BPLUS_BOARD = """\
 
 APLUS_BOARD = """\
 {style:white on green},--------------------------.{style:reset}
-{style:white on green}| {P1:{style} col2}{style:white on green} P1  |{style:reset}
+{style:white on green}| {J8:{style} col2}{style:white on green} J8  |{style:reset}
-{style:white on green}| {P1:{style} col1}{style:white on green}     |{style:reset}
+{style:white on green}| {J8:{style} col1}{style:white on green}     |{style:reset}
 {style:white on green}|                          |{style:reset}
 {style:white on green}|      {style:bold}Pi Model {model:2s} V{pcb_revision:3s}{style:normal}    |{style:reset}
 {style:white on green}|      {style:on black}+----+{style:on green}           {style:black on white}+===={style:reset}
@@ -149,8 +149,8 @@ APLUS_BOARD = """\
 
 ZERO12_BOARD = """\
 {style:white on green},-------------------------.{style:reset}
-{style:white on green}| {P1:{style} col2}{style:white on green} P1 |{style:reset}
+{style:white on green}| {J8:{style} col2}{style:white on green} J8 |{style:reset}
-{style:white on green}| {P1:{style} col1}{style:white on green}    |{style:reset}
+{style:white on green}| {J8:{style} col1}{style:white on green}    |{style:reset}
 {style:black on white}---+{style:white on green}       {style:on black}+---+{style:on green}  {style:bold}PiZero{style:normal}  |{style:reset}
 {style:black on white} sd|{style:white on green}       {style:on black}|SoC|{style:on green}   {style:bold}V{pcb_revision:3s}{style:normal}   |{style:reset}
 {style:black on white}---+|hdmi|{style:white on green} {style:on black}+---+{style:on green}  {style:black on white}usb{style:on green} {style:black on white}pwr{style:white on green} |{style:reset}
@@ -158,8 +158,8 @@ ZERO12_BOARD = """\
 
 ZERO13_BOARD = """\
 {style:white on green}.-------------------------.{style:reset}
-{style:white on green}| {P1:{style} col2}{style:white on green} P1 |{style:reset}
+{style:white on green}| {J8:{style} col2}{style:white on green} J8 |{style:reset}
-{style:white on green}| {P1:{style} col1}{style:white on green}   {style:black on white}|c{style:reset}
+{style:white on green}| {J8:{style} col1}{style:white on green}   {style:black on white}|c{style:reset}
 {style:black on white}---+{style:white on green}       {style:on black}+---+{style:on green} {style:bold}Pi{model:6s}{style:normal}{style:black on white}|s{style:reset}
 {style:black on white} sd|{style:white on green}       {style:on black}|SoC|{style:on green}   {style:bold}V{pcb_revision:3s}{style:normal}  {style:black on white}|i{style:reset}
 {style:black on white}---+|hdmi|{style:white on green} {style:on black}+---+{style:on green}  {style:black on white}usb{style:on green} {style:on white}pwr{style:white on green} |{style:reset}
@@ -216,7 +216,7 @@ REV2_P5 = {
     7:  (GND,    False), 8:  (GND,    False),
     }
 
-PLUS_P1 = {
+PLUS_J8 = {
     1:  (V3_3,   False), 2:  (V5,     False),
     3:  (GPIO2,  True),  4:  (V5,     False),
     5:  (GPIO3,  True),  6:  (GND,    False),
@@ -379,12 +379,12 @@ PI_REVISIONS = {
     0xd:      ('B',    '2.0', '2012Q4', 'BCM2835', 'Egoman',    512,  'SD',      2,  1,  False, False, 1,  1,  {'P1': REV2_P1, 'P5': REV2_P5}, REV2_BOARD,   ),
     0xe:      ('B',    '2.0', '2012Q4', 'BCM2835', 'Sony',      512,  'SD',      2,  1,  False, False, 1,  1,  {'P1': REV2_P1, 'P5': REV2_P5}, REV2_BOARD,   ),
     0xf:      ('B',    '2.0', '2012Q4', 'BCM2835', 'Qisda',     512,  'SD',      2,  1,  False, False, 1,  1,  {'P1': REV2_P1, 'P5': REV2_P5}, REV2_BOARD,   ),
-    0x10:     ('B+',   '1.2', '2014Q3', 'BCM2835', 'Sony',      512,  'MicroSD', 4,  1,  False, False, 1,  1,  {'P1': PLUS_P1},                BPLUS_BOARD,  ),
+    0x10:     ('B+',   '1.2', '2014Q3', 'BCM2835', 'Sony',      512,  'MicroSD', 4,  1,  False, False, 1,  1,  {'J8': PLUS_J8},                BPLUS_BOARD,  ),
     0x11:     ('CM',   '1.1', '2014Q2', 'BCM2835', 'Sony',      512,  'eMMC',    1,  0,  False, False, 2,  2,  {'SODIMM': CM_SODIMM},          CM_BOARD,     ),
-    0x12:     ('A+',   '1.1', '2014Q4', 'BCM2835', 'Sony',      256,  'MicroSD', 1,  0,  False, False, 1,  1,  {'P1': PLUS_P1},                APLUS_BOARD,  ),
+    0x12:     ('A+',   '1.1', '2014Q4', 'BCM2835', 'Sony',      256,  'MicroSD', 1,  0,  False, False, 1,  1,  {'J8': PLUS_J8},                APLUS_BOARD,  ),
-    0x13:     ('B+',   '1.2', '2015Q1', 'BCM2835', 'Egoman',    512,  'MicroSD', 4,  1,  False, False, 1,  1,  {'P1': PLUS_P1},                BPLUS_BOARD,  ),
+    0x13:     ('B+',   '1.2', '2015Q1', 'BCM2835', 'Egoman',    512,  'MicroSD', 4,  1,  False, False, 1,  1,  {'J8': PLUS_J8},                BPLUS_BOARD,  ),
     0x14:     ('CM',   '1.1', '2014Q2', 'BCM2835', 'Embest',    512,  'eMMC',    1,  0,  False, False, 2,  2,  {'SODIMM': CM_SODIMM},          CM_BOARD,     ),
-    0x15:     ('A+',   '1.1', '2014Q4', 'BCM2835', 'Embest',    256,  'MicroSD', 1,  0,  False, False, 1,  1,  {'P1': PLUS_P1},                APLUS_BOARD,  ),
+    0x15:     ('A+',   '1.1', '2014Q4', 'BCM2835', 'Embest',    256,  'MicroSD', 1,  0,  False, False, 1,  1,  {'J8': PLUS_J8},                APLUS_BOARD,  ),
     }
 
 
@@ -529,7 +529,8 @@ class HeaderInfo(namedtuple('HeaderInfo', (
 
         from gpiozero import *
 
-        print('{0:full}'.format(pi_info().headers['P1']))
+        print('{0}'.format(pi_info().headers['J8']))
+        print('{0:full}'.format(pi_info().headers['J8']))
         print('{0:col2}'.format(pi_info().headers['P1']))
         print('{0:row1}'.format(pi_info().headers['P1']))
 
@@ -537,10 +538,9 @@ class HeaderInfo(namedtuple('HeaderInfo', (
     the use of `ANSI color codes`_. If neither is specified, ANSI codes will
     only be used if stdout is detected to be a tty::
 
-        print('{0:color row2}'.format(pi_info().headers['P1'])) # force use of ANSI codes
+        print('{0:color row2}'.format(pi_info().headers['J8'])) # force use of ANSI codes
         print('{0:mono row2}'.format(pi_info().headers['P1'])) # force plain ASCII
 
-    .. _ANSI color codes: https://en.wikipedia.org/wiki/ANSI_escape_code
     The following attributes are defined:
 
     .. automethod:: pprint
@@ -548,7 +548,7 @@ class HeaderInfo(namedtuple('HeaderInfo', (
     .. attribute:: name
 
         The name of the header, typically as it appears silk-screened on the
-        board (e.g. "P1").
+        board (e.g. "P1" or "J8").
 
     .. attribute:: rows
 
@@ -561,6 +561,8 @@ class HeaderInfo(namedtuple('HeaderInfo', (
     .. attribute:: pins
 
         A dictionary mapping physical pin numbers to :class:`PinInfo` tuples.
+
+    .. _ANSI color codes: https://en.wikipedia.org/wiki/ANSI_escape_code
     """
     __slots__ = () # workaround python issue #24931
 
@@ -685,6 +687,7 @@ class PiBoardInfo(namedtuple('PiBoardInfo', (
 
         from gpiozero import *
 
+        print('{0}'.format(pi_info()))
         print('{0:full}'.format(pi_info()))
         print('{0:board}'.format(pi_info()))
         print('{0:specs}'.format(pi_info()))
@@ -801,8 +804,8 @@ class PiBoardInfo(namedtuple('PiBoardInfo', (
 
         A dictionary which maps header labels to :class:`HeaderInfo` tuples.
         For example, to obtain information about header P1 you would query
-        ``headers['P1']``. To obtain information about pin 12 on header P1 you
+        ``headers['P1']``. To obtain information about pin 12 on header J8 you
-        would query ``headers['P1'].pins[12]``.
+        would query ``headers['J8'].pins[12]``.
 
         A rendered version of this data can be obtained by using the
         :class:`PiBoardInfo` object in a format string::
@@ -937,10 +940,10 @@ class PiBoardInfo(namedtuple('PiBoardInfo', (
                     }.get(model, csi)
                 headers = {
                     'A':   {'P1': REV2_P1, 'P5': REV2_P5},
-                    'B':   {'P1': REV2_P1, 'P5': REV2_P5} if pcb_revision == '2.0' else {'P1': REV1_P1},
+                    'B':   {'P1': REV1_P1} if pcb_revision == '1.0' else {'P1': REV2_P1, 'P5': REV2_P5},
                     'CM':  {'SODIMM': CM_SODIMM},
                     'CM3': {'SODIMM': CM3_SODIMM},
-                    }.get(model, {'P1': PLUS_P1})
+                    }.get(model, {'J8': PLUS_J8})
                 board = {
                     'A':      A_BOARD,
                     'B':      REV1_BOARD if pcb_revision == '1.0' else REV2_BOARD,
@@ -1115,8 +1118,8 @@ class PiBoardInfo(namedtuple('PiBoardInfo', (
         """
         Pretty-print a representation of the board along with header diagrams.
 
-        If *color* is ``None`` (the default, the diagram will include ANSI
+        If *color* is ``None`` (the default), the diagram will include ANSI
-        color codes if stdout is a color-capable terminal). Otherwise *color*
+        color codes if stdout is a color-capable terminal. Otherwise *color*
         can be set to ``True`` or ``False`` to force color or monochrome
         output.
         """
@@ -1134,13 +1137,10 @@ def pi_info(revision=None):
         the model of Pi it is running on and return information about that.
     """
     if revision is None:
-        # NOTE: This import is declared locally for two reasons. Firstly it
+        # The reason this import is located here is to avoid a circular
-        # avoids a circular dependency (devices->pins->pins.data->devices).
+        # dependency; devices->pins.local->pins.data->devices
-        # Secondly, pin_factory is one global which might potentially be
+        from ..devices import Device
-        # re-written by a user's script at runtime hence we should re-import
+        result = Device._pin_factory.pi_info
-        # here in case it's changed since initialization
-        from ..devices import pin_factory
-        result = pin_factory.pi_info()
         if result is None:
             raise PinUnknownPi('The default pin_factory is not attached to a Pi')
         else:

gpiozero/pins/local.py

@@ -0,0 +1,241 @@
+from __future__ import (
+    unicode_literals,
+    absolute_import,
+    print_function,
+    division,
+    )
+str = type('')
+
+import io
+import weakref
+import warnings
+
+try:
+    from spidev import SpiDev
+except ImportError:
+    SpiDev = None
+
+from . import SPI
+from .pi import PiFactory, PiPin
+from .spi import SPISoftwareBus
+from ..devices import Device, SharedMixin
+from ..output_devices import OutputDevice
+from ..exc import DeviceClosed, PinUnknownPi, SPIInvalidClockMode
+
+
+class LocalPiFactory(PiFactory):
+    """
+    Abstract base class representing pins attached locally to a Pi. This forms
+    the base class for local-only pin interfaces (:class:`RPiGPIOPin`,
+    :class:`RPIOPin`, and :class:`NativePin`).
+    """
+    pins = {}
+
+    def __init__(self):
+        super(LocalPiFactory, self).__init__()
+        self.spi_hardware_class = LocalPiHardwareSPI
+        self.spi_software_class = LocalPiSoftwareSPI
+        self.shared_spi_hardware_class = LocalPiHardwareSPIShared
+        self.shared_spi_software_class = LocalPiSoftwareSPIShared
+        # Override the pins dict to be this class' pins dict. This is a bit of
+        # a dirty hack, but ensures that anyone evil enough to mix pin
+        # implementations doesn't try and control the same pin with different
+        # backends
+        self.pins = LocalPiFactory.pins
+
+    def _get_address(self):
+        return ('localhost',)
+
+    def _get_revision(self):
+        # Cache the result as we can reasonably assume it won't change during
+        # runtime (this is LocalPin after all; descendents that deal with
+        # remote Pis should inherit from Pin instead)
+        with io.open('/proc/cpuinfo', 'r') as f:
+            for line in f:
+                if line.startswith('Revision'):
+                    revision = line.split(':')[1].strip().lower()
+                    overvolted = revision.startswith('100')
+                    if overvolted:
+                        revision = revision[-4:]
+                    return revision
+        raise PinUnknownPi('unable to locate Pi revision in /proc/cpuinfo')
+
+
+class LocalPiPin(PiPin):
+    """
+    Abstract base class representing a multi-function GPIO pin attached to the
+    local Raspberry Pi.
+    """
+    pass
+
+
+class LocalPiHardwareSPI(SPI, Device):
+    def __init__(self, factory, port, device):
+        if SpiDev is None:
+            raise ImportError('failed to import spidev')
+        self._port = port
+        self._device = device
+        self._intf = None
+        self._address = factory.address + ('SPI(port=%d, device=%d)' % (port, device),)
+        super(LocalPiHardwareSPI, self).__init__()
+        self._reserve_pins(
+            factory.pin_address(11),
+            factory.pin_address(10),
+            factory.pin_address(9),
+            factory.pin_address((8, 7)[device])
+            )
+        self._intf = SpiDev()
+        self._intf.open(port, device)
+        self._intf.max_speed_hz = 500000
+
+    def _conflicts_with(self, other):
+        return not (
+            isinstance(other, LocalPiHardwareSPI) and
+            (self._port, self._device) != (other._port, other._device)
+            )
+
+    def close(self):
+        if self._intf:
+            try:
+                self._intf.close()
+            finally:
+                self._intf = None
+        self._release_all()
+        super(LocalPiHardwareSPI, self).close()
+
+    @property
+    def closed(self):
+        return self._intf is None
+
+    def __repr__(self):
+        try:
+            self._check_open()
+            return 'SPI(port=%d, device=%d)' % (self._port, self._device)
+        except DeviceClosed:
+            return 'SPI(closed)'
+
+    def transfer(self, data):
+        """
+        Writes data (a list of integer words where each word is assumed to have
+        :attr:`bits_per_word` bits or less) to the SPI interface, and reads an
+        equivalent number of words, returning them as a list of integers.
+        """
+        return self._intf.xfer2(data)
+
+    def _get_clock_mode(self):
+        return self._intf.mode
+
+    def _set_clock_mode(self, value):
+        self._intf.mode = value
+
+    def _get_lsb_first(self):
+        return self._intf.lsbfirst
+
+    def _set_lsb_first(self, value):
+        self._intf.lsbfirst = bool(value)
+
+    def _get_select_high(self):
+        return self._intf.cshigh
+
+    def _set_select_high(self, value):
+        self._intf.cshigh = bool(value)
+
+    def _get_bits_per_word(self):
+        return self._intf.bits_per_word
+
+    def _set_bits_per_word(self, value):
+        self._intf.bits_per_word = value
+
+
+class LocalPiSoftwareSPI(SPI, OutputDevice):
+    def __init__(self, factory, clock_pin, mosi_pin, miso_pin, select_pin):
+        self._bus = None
+        self._address = factory.address + (
+            'SPI(clock_pin=%d, mosi_pin=%d, miso_pin=%d, select_pin=%d)' % (
+            clock_pin, mosi_pin, miso_pin, select_pin),
+            )
+        super(LocalPiSoftwareSPI, self).__init__(select_pin, active_high=False)
+        try:
+            self._clock_phase = False
+            self._lsb_first = False
+            self._bits_per_word = 8
+            self._bus = SPISoftwareBus(clock_pin, mosi_pin, miso_pin)
+        except:
+            self.close()
+            raise
+
+    def close(self):
+        if self._bus:
+            self._bus.close()
+            self._bus = None
+        super(LocalPiSoftwareSPI, self).close()
+
+    @property
+    def closed(self):
+        return self._bus is None
+
+    def __repr__(self):
+        try:
+            self._check_open()
+            return 'SPI(clock_pin=%d, mosi_pin=%d, miso_pin=%d, select_pin=%d)' % (
+                self._bus.clock.pin.number,
+                self._bus.mosi.pin.number,
+                self._bus.miso.pin.number,
+                self.pin.number)
+        except DeviceClosed:
+            return 'SPI(closed)'
+
+    def transfer(self, data):
+        with self._bus.lock:
+            self.on()
+            try:
+                return self._bus.transfer(
+                    data, self._clock_phase, self._lsb_first, self._bits_per_word)
+            finally:
+                self.off()
+
+    def _get_clock_mode(self):
+        with self._bus.lock:
+            return (not self._bus.clock.active_high) << 1 | self._clock_phase
+
+    def _set_clock_mode(self, value):
+        if not (0 <= value < 4):
+            raise SPIInvalidClockMode("%d is not a valid clock mode" % value)
+        with self._bus.lock:
+            self._bus.clock.active_high = not (value & 2)
+            self._clock_phase = bool(value & 1)
+
+    def _get_lsb_first(self):
+        return self._lsb_first
+
+    def _set_lsb_first(self, value):
+        self._lsb_first = bool(value)
+
+    def _get_bits_per_word(self):
+        return self._bits_per_word
+
+    def _set_bits_per_word(self, value):
+        if value < 1:
+            raise ValueError('bits_per_word must be positive')
+        self._bits_per_word = int(value)
+
+    def _get_select_high(self):
+        return self.active_high
+
+    def _set_select_high(self, value):
+        with self._bus.lock:
+            self.active_high = value
+            self.off()
+
+
+class LocalPiHardwareSPIShared(SharedMixin, LocalPiHardwareSPI):
+    @classmethod
+    def _shared_key(cls, factory, port, device):
+        return (port, device)
+
+
+class LocalPiSoftwareSPIShared(SharedMixin, LocalPiSoftwareSPI):
+    @classmethod
+    def _shared_key(cls, factory, clock_pin, mosi_pin, miso_pin, select_pin):
+        return (select_pin,)
+

gpiozero/pins/mock.py

@@ -15,56 +15,28 @@ try:
 except ImportError:
     from ..compat import isclose
 
-from . import Pin
+from ..exc import PinPWMUnsupported, PinSetInput, PinFixedPull
-from .data import pi_info
+from ..devices import Device
-from ..exc import PinSetInput, PinPWMUnsupported, PinFixedPull
+from .pi import PiPin
+from .local import LocalPiFactory
 
 
 PinState = namedtuple('PinState', ('timestamp', 'state'))
 
-class MockPin(Pin):
+class MockPin(PiPin):
     """
     A mock pin used primarily for testing. This class does *not* support PWM.
     """
 
-    _PINS = {}
+    def __init__(self, factory, number):
-
+        super(MockPin, self).__init__(factory, number)
-    @classmethod
+        self._function = 'input'
-    def clear_pins(cls):
+        self._state = False
-        cls._PINS.clear()
+        self._pull = 'floating'
-
+        self._bounce = None
-    @classmethod
+        self._edges = 'both'
-    def pi_info(cls):
+        self._when_changed = None
-        return pi_info('a21041') # Pretend we're a Pi 2B
+        self.clear_states()
-
-    def __new__(cls, number):
-        if not (0 <= number < 54):
-            raise ValueError('invalid pin %d specified (must be 0..53)' % number)
-        try:
-            old_pin = cls._PINS[number]
-        except KeyError:
-            self = super(MockPin, cls).__new__(cls)
-            cls._PINS[number] = self
-            self._number = number
-            self._function = 'input'
-            self._state = False
-            self._pull = 'floating'
-            self._bounce = None
-            self._edges = 'both'
-            self._when_changed = None
-            self.clear_states()
-            return self
-        # Ensure the pin class expected supports PWM (or not)
-        if issubclass(cls, MockPWMPin) != isinstance(old_pin, MockPWMPin):
-            raise ValueError('pin %d is already in use as a %s' % (number, old_pin.__class__.__name__))
-        return old_pin
-
-    def __repr__(self):
-        return 'MOCK%d' % self._number
-
-    @property
-    def number(self):
-        return self._number
 
     def close(self):
         self.when_changed = None
@@ -186,8 +158,8 @@ class MockChargingPin(MockPin):
     (as if attached to, e.g. a typical circuit using an LDR and a capacitor
     to time the charging rate).
     """
-    def __init__(self, number):
+    def __init__(self, factory, number):
-        super(MockChargingPin, self).__init__()
+        super(MockChargingPin, self).__init__(factory, number)
         self.charge_time = 0.01 # dark charging time
         self._charge_stop = Event()
         self._charge_thread = None
@@ -225,8 +197,8 @@ class MockTriggerPin(MockPin):
     corresponding pin instance. When this pin is driven high it will trigger
     the echo pin to drive high for the echo time.
     """
-    def __init__(self, number):
+    def __init__(self, factory, number):
-        super(MockTriggerPin, self).__init__()
+        super(MockTriggerPin, self).__init__(factory, number)
         self.echo_pin = None
         self.echo_time = 0.04 # longest echo time
         self._echo_thread = None
@@ -250,8 +222,8 @@ class MockPWMPin(MockPin):
     """
     This derivative of :class:`MockPin` adds PWM support.
     """
-    def __init__(self, number):
+    def __init__(self, factory, number):
-        super(MockPWMPin, self).__init__()
+        super(MockPWMPin, self).__init__(factory, number)
         self._frequency = None
 
     def close(self):
@@ -283,8 +255,8 @@ class MockSPIClockPin(MockPin):
     rather, construct a :class:`MockSPIDevice` with various pin numbers, and
     this class will be used for the clock pin.
     """
-    def __init__(self, number):
+    def __init__(self, factory, number):
-        super(MockSPIClockPin, self).__init__()
+        super(MockSPIClockPin, self).__init__(factory, number)
         if not hasattr(self, 'spi_devices'):
             self.spi_devices = []
 
@@ -301,8 +273,8 @@ class MockSPISelectPin(MockPin):
     tests; rather, construct a :class:`MockSPIDevice` with various pin numbers,
     and this class will be used for the select pin.
     """
-    def __init__(self, number):
+    def __init__(self, factory, number):
-        super(MockSPISelectPin, self).__init__()
+        super(MockSPISelectPin, self).__init__(factory, number)
         if not hasattr(self, 'spi_device'):
             self.spi_device = None
 
@@ -314,13 +286,13 @@ class MockSPISelectPin(MockPin):
 
 class MockSPIDevice(object):
     def __init__(
-            self, clock_pin, mosi_pin, miso_pin, select_pin=None,
+            self, clock_pin, mosi_pin=None, miso_pin=None, select_pin=None,
             clock_polarity=False, clock_phase=False, lsb_first=False,
             bits_per_word=8, select_high=False):
-        self.clock_pin = MockSPIClockPin(clock_pin)
+        self.clock_pin = Device._pin_factory.pin(clock_pin, pin_class=MockSPIClockPin)
-        self.mosi_pin = None if mosi_pin is None else MockPin(mosi_pin)
+        self.mosi_pin = None if mosi_pin is None else Device._pin_factory.pin(mosi_pin)
-        self.miso_pin = None if miso_pin is None else MockPin(miso_pin)
+        self.miso_pin = None if miso_pin is None else Device._pin_factory.pin(miso_pin)
-        self.select_pin = None if select_pin is None else MockSPISelectPin(select_pin)
+        self.select_pin = None if select_pin is None else Device._pin_factory.pin(select_pin, pin_class=MockSPISelectPin)
         self.clock_polarity = clock_polarity
         self.clock_phase = clock_phase
         self.lsb_first = lsb_first
@@ -413,3 +385,34 @@ class MockSPIDevice(object):
             bits = reversed(bits)
         self.tx_buf.extend(bits)
 
+
+class MockFactory(LocalPiFactory):
+    def __init__(self, revision='a21041', pin_class=MockPin):
+        super(MockFactory, self).__init__()
+        self._revision = revision
+        self.pin_class = pin_class
+
+    def _get_address(self):
+        return ('mock',)
+
+    def _get_revision(self):
+        return self._revision
+
+    def reset(self):
+        self.pins.clear()
+
+    def pin(self, spec, pin_class=None):
+        if pin_class is None:
+            pin_class = self.pin_class
+        n = self._to_gpio(spec)
+        try:
+            pin = self.pins[n]
+        except KeyError:
+            pin = pin_class(self, n)
+            self.pins[n] = pin
+        else:
+            # Ensure the pin class expected supports PWM (or not)
+            if issubclass(pin_class, MockPWMPin) != isinstance(pin, MockPWMPin):
+                raise ValueError('pin %d is already in use as a %s' % (n, pin.__class__.__name__))
+        return pin
+

gpiozero/pins/native.py

@@ -13,20 +13,18 @@ import mmap
 import errno
 import struct
 import warnings
+import weakref
 from time import sleep
 from threading import Thread, Event, Lock
 from collections import Counter
 
-from . import LocalPin, PINS_CLEANUP
+from .local import LocalPiPin, LocalPiFactory
-from .data import pi_info
 from ..exc import (
     PinInvalidPull,
     PinInvalidEdges,
     PinInvalidFunction,
     PinFixedPull,
     PinSetInput,
-    PinNonPhysical,
-    PinNoPins,
     )
 
 
@@ -149,7 +147,7 @@ class GPIOFS(object):
                     f.write(str(pin).encode('ascii'))
 
 
-class NativePin(LocalPin):
+class NativeFactory(LocalPiFactory):
     """
     Uses a built-in pure Python implementation to interface to the Pi's GPIO
     pins. This is the default pin implementation if no third-party libraries
@@ -169,10 +167,17 @@ class NativePin(LocalPin):
 
         led = LED(NativePin(12))
     """
+    def __init__(self):
+        super(NativeFactory, self).__init__()
+        self.mem = GPIOMemory()
+        self.pin_class = NativePin
 
-    _MEM = None
+    def close(self):
-    _PINS = {}
+        super(NativeFactory, self).close()
+        self.mem.close()
 
+
+class NativePin(LocalPiPin):
     GPIO_FUNCTIONS = {
         'input':   0b000,
         'output':  0b001,
@@ -202,89 +207,62 @@ class NativePin(LocalPin):
     GPIO_PULL_UP_NAMES = {v: k for (k, v) in GPIO_PULL_UPS.items()}
     GPIO_EDGES_NAMES = {v: k for (k, v) in GPIO_EDGES.items()}
 
-    PI_INFO = None
+    def __init__(self, factory, number):
-
+        super(NativePin, self).__init__(factory, number)
-    def __new__(cls, number):
+        self._func_offset = self.factory.mem.GPFSEL_OFFSET + (number // 10)
-        if not cls._PINS:
+        self._func_shift = (number % 10) * 3
-            cls._MEM = GPIOMemory()
+        self._set_offset = self.factory.mem.GPSET_OFFSET + (number // 32)
-            PINS_CLEANUP.append(cls._MEM.close)
+        self._set_shift = number % 32
-        if cls.PI_INFO is None:
+        self._clear_offset = self.factory.mem.GPCLR_OFFSET + (number // 32)
-            cls.PI_INFO = pi_info()
+        self._clear_shift = number % 32
-        if not (0 <= number < 54):
+        self._level_offset = self.factory.mem.GPLEV_OFFSET + (number // 32)
-            raise ValueError('invalid pin %d specified (must be 0..53)' % number)
+        self._level_shift = number % 32
-        try:
+        self._pull_offset = self.factory.mem.GPPUDCLK_OFFSET + (number // 32)
-            return cls._PINS[number]
+        self._pull_shift = number % 32
-        except KeyError:
+        self._edge_offset = self.factory.mem.GPEDS_OFFSET + (number // 32)
-            self = super(NativePin, cls).__new__(cls)
+        self._edge_shift = number % 32
-            try:
+        self._rising_offset = self.factory.mem.GPREN_OFFSET + (number // 32)
-                cls.PI_INFO.physical_pin('GPIO%d' % number)
+        self._rising_shift = number % 32
-            except PinNoPins:
+        self._falling_offset = self.factory.mem.GPFEN_OFFSET + (number // 32)
-                warnings.warn(
+        self._falling_shift = number % 32
-                    PinNonPhysical(
+        self._when_changed = None
-                        'no physical pins exist for GPIO%d' % number))
+        self._change_thread = None
-            self._number = number
+        self._change_event = Event()
-            self._func_offset = self._MEM.GPFSEL_OFFSET + (number // 10)
+        self.function = 'input'
-            self._func_shift = (number % 10) * 3
+        self.pull = 'up' if factory.pi_info.pulled_up('GPIO%d' % number) else 'floating'
-            self._set_offset = self._MEM.GPSET_OFFSET + (number // 32)
+        self.bounce = None
-            self._set_shift = number % 32
+        self.edges = 'both'
-            self._clear_offset = self._MEM.GPCLR_OFFSET + (number // 32)
-            self._clear_shift = number % 32
-            self._level_offset = self._MEM.GPLEV_OFFSET + (number // 32)
-            self._level_shift = number % 32
-            self._pull_offset = self._MEM.GPPUDCLK_OFFSET + (number // 32)
-            self._pull_shift = number % 32
-            self._edge_offset = self._MEM.GPEDS_OFFSET + (number // 32)
-            self._edge_shift = number % 32
-            self._rising_offset = self._MEM.GPREN_OFFSET + (number // 32)
-            self._rising_shift = number % 32
-            self._falling_offset = self._MEM.GPFEN_OFFSET + (number // 32)
-            self._falling_shift = number % 32
-            self._when_changed = None
-            self._change_thread = None
-            self._change_event = Event()
-            self.function = 'input'
-            self.pull = 'up' if cls.PI_INFO.pulled_up('GPIO%d' % number) else 'floating'
-            self.bounce = None
-            self.edges = 'both'
-            cls._PINS[number] = self
-            return self
-
-    def __repr__(self):
-        return "GPIO%d" % self._number
-
-    @property
-    def number(self):
-        return self._number
 
     def close(self):
+        self.frequency = None
         self.when_changed = None
         self.function = 'input'
-        self.pull = 'up' if self.PI_INFO.pulled_up('GPIO%d' % self.number) else 'floating'
+        self.pull = 'up' if self.factory.pi_info.pulled_up('GPIO%d' % self.number) else 'floating'
 
     def _get_function(self):
-        return self.GPIO_FUNCTION_NAMES[(self._MEM[self._func_offset] >> self._func_shift) & 7]
+        return self.GPIO_FUNCTION_NAMES[(self.factory.mem[self._func_offset] >> self._func_shift) & 7]
 
     def _set_function(self, value):
         try:
             value = self.GPIO_FUNCTIONS[value]
         except KeyError:
             raise PinInvalidFunction('invalid function "%s" for pin %r' % (value, self))
-        self._MEM[self._func_offset] = (
+        self.factory.mem[self._func_offset] = (
-            self._MEM[self._func_offset]
+            self.factory.mem[self._func_offset]
             & ~(7 << self._func_shift)
             | (value << self._func_shift)
             )
 
     def _get_state(self):
-        return bool(self._MEM[self._level_offset] & (1 << self._level_shift))
+        return bool(self.factory.mem[self._level_offset] & (1 << self._level_shift))
 
     def _set_state(self, value):
         if self.function == 'input':
             raise PinSetInput('cannot set state of pin %r' % self)
         if value:
-            self._MEM[self._set_offset] = 1 << self._set_shift
+            self.factory.mem[self._set_offset] = 1 << self._set_shift
         else:
-            self._MEM[self._clear_offset] = 1 << self._clear_shift
+            self.factory.mem[self._clear_offset] = 1 << self._clear_shift
 
     def _get_pull(self):
         return self.GPIO_PULL_UP_NAMES[self._pull]
@@ -292,23 +270,23 @@ class NativePin(LocalPin):
     def _set_pull(self, value):
         if self.function != 'input':
             raise PinFixedPull('cannot set pull on non-input pin %r' % self)
-        if value != 'up' and self.PI_INFO.pulled_up('GPIO%d' % self.number):
+        if value != 'up' and self.factory.pi_info.pulled_up('GPIO%d' % self.number):
             raise PinFixedPull('%r has a physical pull-up resistor' % self)
         try:
             value = self.GPIO_PULL_UPS[value]
         except KeyError:
             raise PinInvalidPull('invalid pull direction "%s" for pin %r' % (value, self))
-        self._MEM[self._MEM.GPPUD_OFFSET] = value
+        self.factory.mem[self.factory.mem.GPPUD_OFFSET] = value
         sleep(0.000000214)
-        self._MEM[self._pull_offset] = 1 << self._pull_shift
+        self.factory.mem[self._pull_offset] = 1 << self._pull_shift
         sleep(0.000000214)
-        self._MEM[self._MEM.GPPUD_OFFSET] = 0
+        self.factory.mem[self.factory.mem.GPPUD_OFFSET] = 0
-        self._MEM[self._pull_offset] = 0
+        self.factory.mem[self._pull_offset] = 0
         self._pull = value
 
     def _get_edges(self):
-        rising = bool(self._MEM[self._rising_offset] & (1 << self._rising_shift))
+        rising = bool(self.factory.mem[self._rising_offset] & (1 << self._rising_shift))
-        falling = bool(self._MEM[self._falling_offset] & (1 << self._falling_shift))
+        falling = bool(self.factory.mem[self._falling_offset] & (1 << self._falling_shift))
         return self.GPIO_EDGES_NAMES[(rising, falling)]
 
     def _set_edges(self, value):
@@ -319,13 +297,13 @@ class NativePin(LocalPin):
         f = self.when_changed
         self.when_changed = None
         try:
-            self._MEM[self._rising_offset] = (
+            self.factory.mem[self._rising_offset] = (
-                self._MEM[self._rising_offset]
+                self.factory.mem[self._rising_offset]
                 & ~(1 << self._rising_shift)
                 | (rising << self._rising_shift)
                 )
-            self._MEM[self._falling_offset] = (
+            self.factory.mem[self._falling_offset] = (
-                self._MEM[self._falling_offset]
+                self.factory.mem[self._falling_offset]
                 & ~(1 << self._falling_shift)
                 | (falling << self._falling_shift)
                 )
@@ -353,9 +331,9 @@ class NativePin(LocalPin):
     def _change_watch(self):
         offset = self._edge_offset
         mask = 1 << self._edge_shift
-        self._MEM[offset] = mask # clear any existing detection bit
+        self.factory.mem[offset] = mask # clear any existing detection bit
         while not self._change_event.wait(0.001):
-            if self._MEM[offset] & mask:
+            if self.factory.mem[offset] & mask:
-                self._MEM[offset] = mask
+                self.factory.mem[offset] = mask
                 self._when_changed()
 

gpiozero/pins/pi.py

@@ -0,0 +1,214 @@
+from __future__ import (
+    unicode_literals,
+    absolute_import,
+    print_function,
+    division,
+    )
+str = type('')
+
+import io
+import weakref
+import warnings
+
+try:
+    from spidev import SpiDev
+except ImportError:
+    SpiDev = None
+
+from . import Factory, Pin
+from .data import pi_info
+from ..exc import (
+    PinNoPins,
+    PinNonPhysical,
+    PinInvalidPin,
+    SPIBadArgs,
+    SPISoftwareFallback,
+    )
+
+
+class PiFactory(Factory):
+    """
+    Abstract base class representing hardware attached to a Raspberry Pi. This
+    forms the base of :class:`LocalPiFactory`.
+    """
+    def __init__(self):
+        self._info = None
+        self.pins = {}
+        self.pin_class = None
+        self.spi_hardware_class = None
+        self.spi_software_class = None
+        self.shared_spi_hardware_class = None
+        self.shared_spi_software_class = None
+
+    def close(self):
+        for pin in self.pins.values():
+            pin.close()
+        self.pins.clear()
+
+    def pin(self, spec):
+        n = self._to_gpio(spec)
+        try:
+            pin = self.pins[n]
+        except KeyError:
+            pin = self.pin_class(self, n)
+            self.pins[n] = pin
+        return pin
+
+    def pin_address(self, spec):
+        n = self._to_gpio(spec)
+        return self.address + ('GPIO%d' % n,)
+
+    def _to_gpio(self, spec):
+        """
+        Converts the pin *spec* to a GPIO port number.
+        """
+        if not 0 <= spec < 54:
+            raise PinInvalidPin('invalid GPIO port %d specified (range 0..53) ' % spec)
+        return spec
+
+    def _get_revision(self):
+        raise NotImplementedError
+
+    def _get_pi_info(self):
+        if self._info is None:
+            self._info = pi_info(self._get_revision())
+        return self._info
+
+    def spi(self, **spi_args):
+        """
+        Returns an SPI interface, for the specified SPI *port* and *device*, or
+        for the specified pins (*clock_pin*, *mosi_pin*, *miso_pin*, and
+        *select_pin*).  Only one of the schemes can be used; attempting to mix
+        *port* and *device* with pin numbers will raise :exc:`SPIBadArgs`.
+
+        If the pins specified match the hardware SPI pins (clock on GPIO11,
+        MOSI on GPIO10, MISO on GPIO9, and chip select on GPIO8 or GPIO7), and
+        the spidev module can be imported, a :class:`SPIHardwareInterface`
+        instance will be returned. Otherwise, a :class:`SPISoftwareInterface`
+        will be returned which will use simple bit-banging to communicate.
+
+        Both interfaces have the same API, support clock polarity and phase
+        attributes, and can handle half and full duplex communications, but the
+        hardware interface is significantly faster (though for many things this
+        doesn't matter).
+        """
+        spi_args, kwargs = self._extract_spi_args(**spi_args)
+        shared = kwargs.pop('shared', False)
+        if kwargs:
+            raise SPIBadArgs(
+                'unrecognized keyword argument %s' % kwargs.popitem()[0])
+        if all((
+                spi_args['clock_pin'] == 11,
+                spi_args['mosi_pin'] == 10,
+                spi_args['miso_pin'] == 9,
+                spi_args['select_pin'] in (7, 8),
+                )):
+            try:
+                hardware_spi_args = {
+                    'port': 0,
+                    'device': {8: 0, 7: 1}[spi_args['select_pin']],
+                    }
+                if shared:
+                    return self.shared_spi_hardware_class(self, **hardware_spi_args)
+                else:
+                    return self.spi_hardware_class(self, **hardware_spi_args)
+            except Exception as e:
+                warnings.warn(
+                    SPISoftwareFallback(
+                        'failed to initialize hardware SPI, falling back to '
+                        'software (error was: %s)' % str(e)))
+        # Convert all pin arguments to integer GPIO numbers. This is necessary
+        # to ensure the shared-key for shared implementations get matched
+        # correctly, and is a bit of a hack for the pigpio bit-bang
+        # implementation which just wants the pin numbers too.
+        spi_args = {
+            key: pin.number if isinstance(pin, Pin) else pin
+            for key, pin in spi_args.items()
+            }
+        if shared:
+            return self.shared_spi_software_class(self, **spi_args)
+        else:
+            return self.spi_software_class(self, **spi_args)
+
+    def _extract_spi_args(self, **kwargs):
+        """
+        Given a set of keyword arguments, splits it into those relevant to SPI
+        implementations and all the rest. SPI arguments are augmented with
+        defaults and converted into the pin format (from the port/device
+        format) if necessary.
+
+        Returns a tuple of ``(spi_args, other_args)``.
+        """
+        pin_defaults = {
+            'clock_pin': 11,
+            'mosi_pin': 10,
+            'miso_pin': 9,
+            'select_pin': 8,
+            }
+        dev_defaults = {
+            'port': 0,
+            'device': 0,
+            }
+        spi_args = {
+            key: value for (key, value) in kwargs.items()
+            if key in pin_defaults or key in dev_defaults
+            }
+        kwargs = {
+            key: value for (key, value) in kwargs.items()
+            if key not in spi_args
+            }
+        if not spi_args:
+            spi_args = pin_defaults
+        elif set(spi_args) <= set(pin_defaults):
+            spi_args = {
+                key: self._to_gpio(spi_args.get(key, default))
+                for key, default in pin_defaults.items()
+                }
+        elif set(spi_args) <= set(dev_defaults):
+            spi_args = {
+                key: spi_args.get(key, default)
+                for key, default in dev_defaults.items()
+                }
+            if spi_args['port'] != 0:
+                raise SPIBadArgs('port 0 is the only valid SPI port')
+            if spi_args['device'] not in (0, 1):
+                raise SPIBadArgs('device must be 0 or 1')
+            spi_args = {
+                key: value if key != 'select_pin' else (8, 7)[spi_args['device']]
+                for key, value in pin_defaults.items()
+                }
+        else:
+            raise SPIBadArgs(
+                'you must either specify port and device, or clock_pin, '
+                'mosi_pin, miso_pin, and select_pin; combinations of the two '
+                'schemes (e.g. port and clock_pin) are not permitted')
+        return spi_args, kwargs
+
+
+class PiPin(Pin):
+    """
+    Abstract base class representing a multi-function GPIO pin attached to a
+    Raspberry Pi.
+    """
+    def __init__(self, factory, number):
+        super(PiPin, self).__init__()
+        try:
+            factory.pi_info.physical_pin('GPIO%d' % number)
+        except PinNoPins:
+            warnings.warn(
+                PinNonPhysical(
+                    'no physical pins exist for GPIO%d' % number))
+        self._factory = weakref.proxy(factory)
+        self._number = number
+
+    @property
+    def number(self):
+        return self._number
+
+    @property
+    def factory(self):
+        return self._factory
+
+    def _get_address(self):
+        return self.factory.address + ('GPIO%d' % self.number,)
+

gpiozero/pins/pigpiod.py

@@ -6,12 +6,15 @@ from __future__ import (
     )
 str = type('')
 
-import warnings
+import weakref
 import pigpio
 import os
 
-from . import Pin
+from . import SPI
+from .pi import PiPin, PiFactory
 from .data import pi_info
+from ..devices import Device
+from ..mixins import SharedMixin
 from ..exc import (
     PinInvalidFunction,
     PinSetInput,
@@ -19,12 +22,12 @@ from ..exc import (
     PinInvalidPull,
     PinInvalidBounce,
     PinInvalidState,
-    PinNonPhysical,
+    SPIBadArgs,
-    PinNoPins,
+    SPIInvalidClockMode,
     )
 
 
-class PiGPIOPin(Pin):
+class PiGPIOFactory(PiFactory):
     """
     Uses the `pigpio`_ library to interface to the Pi's GPIO pins. The pigpio
     library relies on a daemon (``pigpiod``) to be running as root to provide
@@ -68,10 +71,65 @@ class PiGPIOPin(Pin):
 
     .. _pigpio: http://abyz.co.uk/rpi/pigpio/
     """
+    def __init__(
+            self, host=os.getenv('PIGPIO_ADDR', 'localhost'),
+            port=int(os.getenv('PIGPIO_PORT', 8888))):
+        super(PiGPIOFactory, self).__init__()
+        self.pin_class = PiGPIOPin
+        self.spi_hardware_class = PiGPIOHardwareSPI
+        self.spi_software_class = PiGPIOSoftwareSPI
+        self.shared_spi_hardware_class = PiGPIOHardwareSPIShared
+        self.shared_spi_software_class = PiGPIOSoftwareSPIShared
+        self._connection = pigpio.pi(host, port)
+        self._host = host
+        self._port = port
+        self._spis = []
 
+    def close(self):
+        super(PiGPIOFactory, self).close()
+        # We *have* to keep track of SPI interfaces constructed with pigpio;
+        # if we fail to close them they prevent future interfaces from using
+        # the same pins
+        if self.connection:
+            while self._spis:
+                self._spis[0].close()
+            self.connection.stop()
+            self._connection = None
+
+    @property
+    def connection(self):
+        # If we're shutting down, the connection may have disconnected itself
+        # already. Unfortunately, the connection's "connected" property is
+        # rather buggy - disconnecting doesn't set it to False! So we're
+        # naughty and check an internal variable instead...
+        try:
+            if self._connection.sl.s is not None:
+                return self._connection
+        except AttributeError:
+            pass
+
+    @property
+    def host(self):
+        return self._host
+
+    @property
+    def port(self):
+        return self._port
+
+    def _get_revision(self):
+        return self.connection.get_hardware_revision()
+
+    def _get_address(self):
+        return ("%s:%d" % (self.host, self.port),)
+
+    def spi(self, **spi_args):
+        intf = super(PiGPIOFactory, self).spi(**spi_args)
+        self._spis.append(intf)
+        return intf
+
+
+class PiGPIOPin(PiPin):
     _CONNECTIONS = {} # maps (host, port) to (connection, pi_info)
-    _PINS = {}
-
     GPIO_FUNCTIONS = {
         'input':   pigpio.INPUT,
         'output':  pigpio.OUTPUT,
@@ -99,101 +157,64 @@ class PiGPIOPin(Pin):
     GPIO_PULL_UP_NAMES = {v: k for (k, v) in GPIO_PULL_UPS.items()}
     GPIO_EDGES_NAMES = {v: k for (k, v) in GPIO_EDGES.items()}
 
-    def __new__(
+    def __init__(self, factory, number):
-            cls, number, host=os.getenv('PIGPIO_ADDR', 'localhost'),
+        super(PiGPIOPin, self).__init__(factory, number)
-            port=int(os.getenv('PIGPIO_PORT', 8888))):
+        self._pull = 'up' if factory.pi_info.pulled_up('GPIO%d' % number) else 'floating'
+        self._pwm = False
+        self._bounce = None
+        self._when_changed = None
+        self._callback = None
+        self._edges = pigpio.EITHER_EDGE
         try:
-            return cls._PINS[(host, port, number)]
+            self.factory.connection.set_mode(self.number, pigpio.INPUT)
-        except KeyError:
+        except pigpio.error as e:
-            self = super(PiGPIOPin, cls).__new__(cls)
+            raise ValueError(e)
-            cls.pi_info(host, port) # implicitly creates connection
+        self.factory.connection.set_pull_up_down(self.number, self.GPIO_PULL_UPS[self._pull])
-            self._connection, self._pi_info = cls._CONNECTIONS[(host, port)]
+        self.factory.connection.set_glitch_filter(self.number, 0)
-            try:
-                self._pi_info.physical_pin('GPIO%d' % number)
-            except PinNoPins:
-                warnings.warn(
-                    PinNonPhysical(
-                        'no physical pins exist for GPIO%d' % number))
-            self._host = host
-            self._port = port
-            self._number = number
-            self._pull = 'up' if self._pi_info.pulled_up('GPIO%d' % number) else 'floating'
-            self._pwm = False
-            self._bounce = None
-            self._when_changed = None
-            self._callback = None
-            self._edges = pigpio.EITHER_EDGE
-            try:
-                self._connection.set_mode(self._number, pigpio.INPUT)
-            except pigpio.error as e:
-                raise ValueError(e)
-            self._connection.set_pull_up_down(self._number, self.GPIO_PULL_UPS[self._pull])
-            self._connection.set_glitch_filter(self._number, 0)
-            cls._PINS[(host, port, number)] = self
-            return self
-
-    def __repr__(self):
-        if self._host == 'localhost':
-            return "GPIO%d" % self._number
-        else:
-            return "GPIO%d on %s:%d" % (self._number, self._host, self._port)
-
-    @property
-    def host(self):
-        return self._host
-
-    @property
-    def port(self):
-        return self._port
-
-    @property
-    def number(self):
-        return self._number
 
     def close(self):
-        # If we're shutting down, the connection may have disconnected itself
+        if self.factory.connection:
-        # already. Unfortunately, the connection's "connected" property is
-        # rather buggy - disconnecting doesn't set it to False! So we're
-        # naughty and check an internal variable instead...
-        if self._connection.sl.s is not None:
             self.frequency = None
             self.when_changed = None
             self.function = 'input'
-            self.pull = 'up' if self._pi_info.pulled_up('GPIO%d' % self.number) else 'floating'
+            self.pull = 'up' if self.factory.pi_info.pulled_up('GPIO%d' % self.number) else 'floating'
+
+    def _get_address(self):
+        return self.factory.address + ('GPIO%d' % self.number,)
 
     def _get_function(self):
-        return self.GPIO_FUNCTION_NAMES[self._connection.get_mode(self._number)]
+        return self.GPIO_FUNCTION_NAMES[self.factory.connection.get_mode(self.number)]
 
     def _set_function(self, value):
         if value != 'input':
             self._pull = 'floating'
         try:
-            self._connection.set_mode(self._number, self.GPIO_FUNCTIONS[value])
+            self.factory.connection.set_mode(self.number, self.GPIO_FUNCTIONS[value])
         except KeyError:
             raise PinInvalidFunction('invalid function "%s" for pin %r' % (value, self))
 
     def _get_state(self):
         if self._pwm:
             return (
-                self._connection.get_PWM_dutycycle(self._number) /
+                self.factory.connection.get_PWM_dutycycle(self.number) /
-                self._connection.get_PWM_range(self._number)
+                self.factory.connection.get_PWM_range(self.number)
                 )
         else:
-            return bool(self._connection.read(self._number))
+            return bool(self.factory.connection.read(self.number))
 
     def _set_state(self, value):
         if self._pwm:
             try:
-                value = int(value * self._connection.get_PWM_range(self._number))
+                value = int(value * self.factory.connection.get_PWM_range(self.number))
-                if value != self._connection.get_PWM_dutycycle(self._number):
+                if value != self.factory.connection.get_PWM_dutycycle(self.number):
-                    self._connection.set_PWM_dutycycle(self._number, value)
+                    self.factory.connection.set_PWM_dutycycle(self.number, value)
             except pigpio.error:
                 raise PinInvalidState('invalid state "%s" for pin %r' % (value, self))
         elif self.function == 'input':
             raise PinSetInput('cannot set state of pin %r' % self)
         else:
             # write forces pin to OUTPUT, hence the check above
-            self._connection.write(self._number, bool(value))
+            self.factory.connection.write(self.number, bool(value))
 
     def _get_pull(self):
         return self._pull
@@ -201,31 +222,31 @@ class PiGPIOPin(Pin):
     def _set_pull(self, value):
         if self.function != 'input':
             raise PinFixedPull('cannot set pull on non-input pin %r' % self)
-        if value != 'up' and self._pi_info.pulled_up('GPIO%d' % self._number):
+        if value != 'up' and self.factory.pi_info.pulled_up('GPIO%d' % self.number):
             raise PinFixedPull('%r has a physical pull-up resistor' % self)
         try:
-            self._connection.set_pull_up_down(self._number, self.GPIO_PULL_UPS[value])
+            self.factory.connection.set_pull_up_down(self.number, self.GPIO_PULL_UPS[value])
             self._pull = value
         except KeyError:
             raise PinInvalidPull('invalid pull "%s" for pin %r' % (value, self))
 
     def _get_frequency(self):
         if self._pwm:
-            return self._connection.get_PWM_frequency(self._number)
+            return self.factory.connection.get_PWM_frequency(self.number)
         return None
 
     def _set_frequency(self, value):
         if not self._pwm and value is not None:
-            self._connection.set_PWM_frequency(self._number, value)
+            self.factory.connection.set_PWM_frequency(self.number, value)
-            self._connection.set_PWM_range(self._number, 10000)
+            self.factory.connection.set_PWM_range(self.number, 10000)
-            self._connection.set_PWM_dutycycle(self._number, 0)
+            self.factory.connection.set_PWM_dutycycle(self.number, 0)
             self._pwm = True
         elif self._pwm and value is not None:
-            if value != self._connection.get_PWM_frequency(self._number):
+            if value != self.factory.connection.get_PWM_frequency(self.number):
-                self._connection.set_PWM_frequency(self._number, value)
+                self.factory.connection.set_PWM_frequency(self.number, value)
-                self._connection.set_PWM_range(self._number, 10000)
+                self.factory.connection.set_PWM_range(self.number, 10000)
         elif self._pwm and value is None:
-            self._connection.write(self._number, 0)
+            self.factory.connection.write(self.number, 0)
             self._pwm = False
 
     def _get_bounce(self):
@@ -236,7 +257,7 @@ class PiGPIOPin(Pin):
             value = 0
         elif value < 0:
             raise PinInvalidBounce('bounce must be 0 or greater')
-        self._connection.set_glitch_filter(self._number, int(value * 1000000))
+        self.factory.connection.set_glitch_filter(self.number, int(value * 1000000))
 
     def _get_edges(self):
         return self.GPIO_EDGES_NAMES[self._edges]
@@ -259,20 +280,224 @@ class PiGPIOPin(Pin):
             self._callback.cancel()
             self._callback = None
         if value is not None:
-            self._callback = self._connection.callback(
+            self._callback = self.factory.connection.callback(
-                    self._number, self._edges,
+                    self.number, self._edges,
                     lambda gpio, level, tick: value())
 
-    @classmethod
+
-    def pi_info(
+class PiGPIOHardwareSPI(SPI, Device):
-            cls, host=os.getenv('PIGPIO_ADDR', 'localhost'),
+    def __init__(self, factory, port, device):
-            port=int(os.getenv('PIGPIO_PORT', 8888))):
+        self._port = port
-        try:
+        self._device = device
-            connection, info = cls._CONNECTIONS[(host, port)]
+        self._factory = weakref.proxy(factory)
-        except KeyError:
+        super(PiGPIOHardwareSPI, self).__init__()
-            connection = pigpio.pi(host, port)
+        self._reserve_pins(*(
-            revision = '%04x' % connection.get_hardware_revision()
+            factory.address + ('GPIO%d' % pin,)
-            info = pi_info(revision)
+            for pin in (11, 10, 9, (8, 7)[device])
-            cls._CONNECTIONS[(host, port)] = (connection, info)
+            ))
-        return info
+        self._mode = 0
+        self._select_high = False
+        self._bits_per_word = 8
+        self._baud = 500000
+        self._handle = self._factory.connection.spi_open(
+            device, self._baud, self._spi_flags())
+
+    def close(self):
+        try:
+            self._factory._spis.remove(self)
+        except (ReferenceError, ValueError):
+            # If the factory has died already or we're not present in its
+            # internal list, ignore the error
+            pass
+        if not self.closed:
+            self._factory.connection.spi_close(self._handle)
+        self._handle = None
+        self._release_all()
+        super(PiGPIOHardwareSPI, self).close()
+
+    @property
+    def closed(self):
+        return self._handle is None or self._factory.connection is None
+
+    @property
+    def factory(self):
+        return self._factory
+
+    def __repr__(self):
+        try:
+            self._check_open()
+            return 'SPI(port=%d, device=%d)' % (self._port, self._device)
+        except DeviceClosed:
+            return 'SPI(closed)'
+
+    def _spi_flags(self):
+        return (
+            self._mode          << 0                  |
+            self._select_high   << (2 + self._device) |
+            self._bits_per_word << 16
+            )
+
+    def _get_clock_mode(self):
+        return self._clock_mode
+
+    def _set_clock_mode(self, value):
+        self._check_open()
+        if not 0 <= value < 4:
+            raise SPIInvalidClockmode("%d is not a valid SPI clock mode" % value)
+        self._factory.connection.spi_close(self._handle)
+        self._clock_mode = value
+        self._handle = self._factory.connection.spi_open(
+            self._device, self._baud, self._spi_flags())
+
+    def _get_select_high(self):
+        return self._select_high
+
+    def _set_select_high(self, value):
+        self._check_open()
+        self._factory.connection.spi_close(self._handle)
+        self._select_high = bool(value)
+        self._handle = self._factory.connection.spi_open(
+            self._device, self._baud, self._spi_flags())
+
+    def _get_bits_per_word(self):
+        return self._bits_per_word
+
+    def _set_bits_per_word(self, value):
+        self._check_open()
+        self._factory.connection.spi_close(self._handle)
+        self._bits_per_word = value
+        self._handle = self._factory.connection.spi_open(
+            self._device, self._baud, self._spi_flags())
+
+    def transfer(self, data):
+        self._check_open()
+        count, data = self._factory.connection.spi_xfer(self._handle, data)
+        if count < 0:
+            raise IOError('SPI transfer error %d' % count)
+        # Convert returned bytearray to list of ints. XXX Not sure how non-byte
+        # sized words (aux intf only) are returned ... padded to 16/32-bits?
+        return [int(b) for b in data]
+
+
+class PiGPIOSoftwareSPI(SPI, Device):
+    def __init__(self, factory, clock_pin, mosi_pin, miso_pin, select_pin):
+        self._select_pin = None
+        self._factory = weakref.proxy(factory)
+        self._address = factory.address + (
+            )
+        super(PiGPIOSoftwareSPI, self).__init__()
+        self._reserve_pins(
+            factory.pin_address(clock_pin),
+            factory.pin_address(mosi_pin),
+            factory.pin_address(miso_pin),
+            factory.pin_address(select_pin),
+            )
+        self._mode = 0
+        self._select_high = False
+        self._lsb_first = False
+        self._baud = 100000
+        try:
+            self._factory.connection.bb_spi_open(
+                select_pin, miso_pin, mosi_pin, clock_pin,
+                self._baud, self._spi_flags())
+            # Only set after opening bb_spi; if that fails then close() will
+            # also fail if bb_spi_close is attempted on an un-open interface
+            self._select_pin = select_pin
+            self._clock_pin = clock_pin
+            self._mosi_pin = mosi_pin
+            self._miso_pin = miso_pin
+        except:
+            self.close()
+            raise
+
+    def close(self):
+        try:
+            self._factory._spis.remove(self)
+        except (ReferenceError, ValueError):
+            # If the factory has died already or we're not present in its
+            # internal list, ignore the error
+            pass
+        if not self.closed:
+            self._factory.connection.bb_spi_close(self._select_pin)
+        self._select_pin = None
+        self._release_all()
+        super(PiGPIOSoftwareSPI, self).close()
+
+    @property
+    def closed(self):
+        return self._select_pin is None or self._factory.connection is None
+
+    def __repr__(self):
+        try:
+            self._check_open()
+            return (
+                'SPI(clock_pin=%d, mosi_pin=%d, miso_pin=%d, select_pin=%d)' % (
+                self._clock_pin, self._mosi_pin, self._miso_pin, self._select_pin
+                ))
+        except DeviceClosed:
+            return 'SPI(closed)'
+
+    def _spi_flags(self):
+        return (
+            self._mode          << 0  |
+            self._select_high   << 2  |
+            self._lsb_first     << 14 |
+            self._lsb_first     << 15
+            )
+
+    def _get_clock_mode(self):
+        return self._clock_mode
+
+    def _set_clock_mode(self, value):
+        self._check_open()
+        if not 0 <= value < 4:
+            raise SPIInvalidClockmode("%d is not a valid SPI clock mode" % value)
+        self._factory.connection.bb_spi_close(self._select_pin)
+        self._clock_mode = value
+        self._factory.connection.bb_spi_open(
+            self._select_pin, self._miso_pin, self._mosi_pin, self._clock_pin,
+            self._baud, self._spi_flags())
+
+    def _get_select_high(self):
+        return self._select_high
+
+    def _set_select_high(self, value):
+        self._check_open()
+        self._factory.connection.bb_spi_close(self._select_pin)
+        self._select_high = bool(value)
+        self._factory.connection.bb_spi_open(
+            self._select_pin, self._miso_pin, self._mosi_pin, self._clock_pin,
+            self._baud, self._spi_flags())
+
+    def _get_lsb_first(self):
+        return self._lsb_first
+
+    def _set_lsb_first(self, value):
+        self._check_open()
+        self._factory.connection.bb_spi_close(self._select_pin)
+        self._lsb_first = bool(value)
+        self._factory.connection.bb_spi_open(
+            self._select_pin, self._miso_pin, self._mosi_pin, self._clock_pin,
+            self._baud, self._spi_flags())
+
+    def transfer(self, data):
+        self._check_open()
+        count, data = self._factory.connection.bb_spi_xfer(self._select_pin, data)
+        if count < 0:
+            raise IOError('SPI transfer error %d' % count)
+        # Convert returned bytearray to list of ints. bb_spi only supports
+        # byte-sized words so no issues here
+        return [int(b) for b in data]
+
+
+class PiGPIOHardwareSPIShared(SharedMixin, PiGPIOHardwareSPI):
+    @classmethod
+    def _shared_key(cls, factory, port, device):
+        return (factory, port, device)
+
+
+class PiGPIOSoftwareSPIShared(SharedMixin, PiGPIOSoftwareSPI):
+    @classmethod
+    def _shared_key(cls, factory, clock_pin, mosi_pin, miso_pin, select_pin):
+        return (factory, select_pin)
 

gpiozero/pins/rpigpio.py

@@ -7,10 +7,10 @@ from __future__ import (
 str = type('')
 
 import warnings
+import weakref
 from RPi import GPIO
 
-from . import LocalPin
+from .local import LocalPiFactory, LocalPiPin
-from .data import pi_info
 from ..exc import (
     PinInvalidFunction,
     PinSetInput,
@@ -19,12 +19,10 @@ from ..exc import (
     PinInvalidState,
     PinInvalidBounce,
     PinPWMFixedValue,
-    PinNonPhysical,
-    PinNoPins,
     )
 
 
-class RPiGPIOPin(LocalPin):
+class RPiGPIOFactory(LocalPiFactory):
     """
     Uses the `RPi.GPIO`_ library to interface to the Pi's GPIO pins. This is
     the default pin implementation if the RPi.GPIO library is installed.
@@ -39,7 +37,7 @@ class RPiGPIOPin(LocalPin):
 
     However, you can also construct RPi.GPIO pins manually if you wish::
 
-        from gpiozero.pins.rpigpio import RPiGPIOPin
+        from gpiozero.pins.rpigpio import RPiGPIOFactory
         from gpiozero import LED
 
         led = LED(RPiGPIOPin(12))
@@ -47,8 +45,18 @@ class RPiGPIOPin(LocalPin):
     .. _RPi.GPIO: https://pypi.python.org/pypi/RPi.GPIO
     """
 
-    _PINS = {}
+    def __init__(self):
+        super(RPiGPIOFactory, self).__init__()
+        GPIO.setmode(GPIO.BCM)
+        GPIO.setwarnings(False)
+        self.pin_class = RPiGPIOPin
 
+    def close(self):
+        super(RPiGPIOFactory, self).close()
+        GPIO.cleanup()
+
+
+class RPiGPIOPin(LocalPiPin):
     GPIO_FUNCTIONS = {
         'input':   GPIO.IN,
         'output':  GPIO.OUT,
@@ -75,69 +83,43 @@ class RPiGPIOPin(LocalPin):
     GPIO_PULL_UP_NAMES = {v: k for (k, v) in GPIO_PULL_UPS.items()}
     GPIO_EDGES_NAMES = {v: k for (k, v) in GPIO_EDGES.items()}
 
-    PI_INFO = None
+    def __init__(self, factory, number):
-
+        super(RPiGPIOPin, self).__init__(factory, number)
-    def __new__(cls, number):
+        self._pull = 'up' if factory.pi_info.pulled_up('GPIO%d' % number) else 'floating'
-        if not cls._PINS:
+        self._pwm = None
-            GPIO.setmode(GPIO.BCM)
+        self._frequency = None
-            GPIO.setwarnings(False)
+        self._duty_cycle = None
-        if cls.PI_INFO is None:
+        self._bounce = -666
-            cls.PI_INFO = pi_info()
+        self._when_changed = None
-        try:
+        self._edges = GPIO.BOTH
-            return cls._PINS[number]
+        GPIO.setup(self.number, GPIO.IN, self.GPIO_PULL_UPS[self._pull])
-        except KeyError:
-            self = super(RPiGPIOPin, cls).__new__(cls)
-            try:
-                cls.PI_INFO.physical_pin('GPIO%d' % number)
-            except PinNoPins:
-                warnings.warn(
-                    PinNonPhysical(
-                        'no physical pins exist for GPIO%d' % number))
-            self._number = number
-            self._pull = 'up' if cls.PI_INFO.pulled_up('GPIO%d' % number) else 'floating'
-            self._pwm = None
-            self._frequency = None
-            self._duty_cycle = None
-            self._bounce = -666
-            self._when_changed = None
-            self._edges = GPIO.BOTH
-            GPIO.setup(self._number, GPIO.IN, self.GPIO_PULL_UPS[self._pull])
-            cls._PINS[number] = self
-            return self
-
-    def __repr__(self):
-        return "GPIO%d" % self._number
-
-    @property
-    def number(self):
-        return self._number
 
     def close(self):
         self.frequency = None
         self.when_changed = None
-        GPIO.cleanup(self._number)
+        GPIO.cleanup(self.number)
 
     def output_with_state(self, state):
         self._pull = 'floating'
-        GPIO.setup(self._number, GPIO.OUT, initial=state)
+        GPIO.setup(self.number, GPIO.OUT, initial=state)
 
     def input_with_pull(self, pull):
-        if pull != 'up' and self.PI_INFO.pulled_up('GPIO%d' % self._number):
+        if pull != 'up' and self.factory.pi_info.pulled_up('GPIO%d' % self.number):
             raise PinFixedPull('%r has a physical pull-up resistor' % self)
         try:
-            GPIO.setup(self._number, GPIO.IN, self.GPIO_PULL_UPS[pull])
+            GPIO.setup(self.number, GPIO.IN, self.GPIO_PULL_UPS[pull])
             self._pull = pull
         except KeyError:
             raise PinInvalidPull('invalid pull "%s" for pin %r' % (pull, self))
 
     def _get_function(self):
-        return self.GPIO_FUNCTION_NAMES[GPIO.gpio_function(self._number)]
+        return self.GPIO_FUNCTION_NAMES[GPIO.gpio_function(self.number)]
 
     def _set_function(self, value):
         if value != 'input':
             self._pull = 'floating'
         if value in ('input', 'output') and value in self.GPIO_FUNCTIONS:
-            GPIO.setup(self._number, self.GPIO_FUNCTIONS[value], self.GPIO_PULL_UPS[self._pull])
+            GPIO.setup(self.number, self.GPIO_FUNCTIONS[value], self.GPIO_PULL_UPS[self._pull])
         else:
             raise PinInvalidFunction('invalid function "%s" for pin %r' % (value, self))
 
@@ -145,7 +127,7 @@ class RPiGPIOPin(LocalPin):
         if self._pwm:
             return self._duty_cycle
         else:
-            return GPIO.input(self._number)
+            return GPIO.input(self.number)
 
     def _set_state(self, value):
         if self._pwm:
@@ -156,7 +138,7 @@ class RPiGPIOPin(LocalPin):
             self._duty_cycle = value
         else:
             try:
-                GPIO.output(self._number, value)
+                GPIO.output(self.number, value)
             except ValueError:
                 raise PinInvalidState('invalid state "%s" for pin %r' % (value, self))
             except RuntimeError:
@@ -168,10 +150,10 @@ class RPiGPIOPin(LocalPin):
     def _set_pull(self, value):
         if self.function != 'input':
             raise PinFixedPull('cannot set pull on non-input pin %r' % self)
-        if value != 'up' and self.PI_INFO.pulled_up('GPIO%d' % self._number):
+        if value != 'up' and self.factory.pi_info.pulled_up('GPIO%d' % self.number):
             raise PinFixedPull('%r has a physical pull-up resistor' % self)
         try:
-            GPIO.setup(self._number, GPIO.IN, self.GPIO_PULL_UPS[value])
+            GPIO.setup(self.number, GPIO.IN, self.GPIO_PULL_UPS[value])
             self._pull = value
         except KeyError:
             raise PinInvalidPull('invalid pull "%s" for pin %r' % (value, self))
@@ -182,7 +164,7 @@ class RPiGPIOPin(LocalPin):
     def _set_frequency(self, value):
         if self._frequency is None and value is not None:
             try:
-                self._pwm = GPIO.PWM(self._number, value)
+                self._pwm = GPIO.PWM(self.number, value)
             except RuntimeError:
                 raise PinPWMFixedValue('cannot start PWM on pin %r' % self)
             self._pwm.start(0)
@@ -228,11 +210,11 @@ class RPiGPIOPin(LocalPin):
         if self._when_changed is None and value is not None:
             self._when_changed = value
             GPIO.add_event_detect(
-                self._number, self._edges,
+                self.number, self._edges,
                 callback=lambda channel: self._when_changed(),
                 bouncetime=self._bounce)
         elif self._when_changed is not None and value is None:
-            GPIO.remove_event_detect(self._number)
+            GPIO.remove_event_detect(self.number)
             self._when_changed = None
         else:
             self._when_changed = value

gpiozero/pins/rpio.py

@@ -8,11 +8,12 @@ str = type('')
 
 
 import warnings
+import weakref
 import RPIO
 import RPIO.PWM
 from RPIO.Exceptions import InvalidChannelException
 
-from . import LocalPin, PINS_CLEANUP
+from .local import LocalPiPin, LocalPiFactory
 from .data import pi_info
 from ..exc import (
     PinInvalidFunction,
@@ -22,12 +23,10 @@ from ..exc import (
     PinInvalidBounce,
     PinInvalidState,
     PinPWMError,
-    PinNonPhysical,
-    PinNoPins,
     )
 
 
-class RPIOPin(LocalPin):
+class RPIOFactory(LocalPiFactory):
     """
     Uses the `RPIO`_ library to interface to the Pi's GPIO pins. This is
     the default pin implementation if the RPi.GPIO library is not installed,
@@ -48,9 +47,22 @@ class RPIOPin(LocalPin):
 
     .. _RPIO: https://pythonhosted.org/RPIO/
     """
+    def __init__(self):
+        super(RPIOFactory, self).__init__()
+        RPIO.setmode(RPIO.BCM)
+        RPIO.setwarnings(False)
+        RPIO.wait_for_interrupts(threaded=True)
+        RPIO.PWM.setup()
+        RPIO.PWM.init_channel(0, 10000)
+        self.pin_class = RPIOPin
 
-    _PINS = {}
+    def close(self):
+        RPIO.PWM.cleanup()
+        RPIO.stop_waiting_for_interrupts()
+        RPIO.cleanup()
 
+
+class RPIOPin(LocalPiPin):
     GPIO_FUNCTIONS = {
         'input':   RPIO.IN,
         'output':  RPIO.OUT,
@@ -66,64 +78,32 @@ class RPIOPin(LocalPin):
     GPIO_FUNCTION_NAMES = {v: k for (k, v) in GPIO_FUNCTIONS.items()}
     GPIO_PULL_UP_NAMES = {v: k for (k, v) in GPIO_PULL_UPS.items()}
 
-    PI_INFO = None
+    def __init__(self, factory, number):
-
+        super(RPIOPin, self).__init__(factory, number)
-    def __new__(cls, number):
+        self._pull = 'up' if factory.pi_info.pulled_up('GPIO%d' % number) else 'floating'
-        if not cls._PINS:
+        self._pwm = False
-            RPIO.setmode(RPIO.BCM)
+        self._duty_cycle = None
-            RPIO.setwarnings(False)
+        self._bounce = None
-            RPIO.wait_for_interrupts(threaded=True)
+        self._when_changed = None
-            RPIO.PWM.setup()
+        self._edges = 'both'
-            RPIO.PWM.init_channel(0, 10000)
-            PINS_CLEANUP.append(RPIO.PWM.cleanup)
-            PINS_CLEANUP.append(RPIO.stop_waiting_for_interrupts)
-            PINS_CLEANUP.append(RPIO.cleanup)
-        if cls.PI_INFO is None:
-            cls.PI_INFO = pi_info()
         try:
-            return cls._PINS[number]
+            RPIO.setup(self.number, RPIO.IN, self.GPIO_PULL_UPS[self._pull])
-        except KeyError:
+        except InvalidChannelException as e:
-            self = super(RPIOPin, cls).__new__(cls)
+            raise ValueError(e)
-            try:
-                cls.PI_INFO.physical_pin('GPIO%d' % number)
-            except PinNoPins:
-                warnings.warn(
-                    PinNonPhysical(
-                        'no physical pins exist for GPIO%d' % number))
-            self._number = number
-            self._pull = 'up' if cls.PI_INFO.pulled_up('GPIO%d' % number) else 'floating'
-            self._pwm = False
-            self._duty_cycle = None
-            self._bounce = None
-            self._when_changed = None
-            self._edges = 'both'
-            try:
-                RPIO.setup(self._number, RPIO.IN, self.GPIO_PULL_UPS[self._pull])
-            except InvalidChannelException as e:
-                raise ValueError(e)
-            cls._PINS[number] = self
-            return self
-
-    def __repr__(self):
-        return "GPIO%d" % self._number
-
-    @property
-    def number(self):
-        return self._number
 
     def close(self):
         self.frequency = None
         self.when_changed = None
-        RPIO.setup(self._number, RPIO.IN, RPIO.PUD_OFF)
+        RPIO.setup(self.number, RPIO.IN, RPIO.PUD_OFF)
 
     def _get_function(self):
-        return self.GPIO_FUNCTION_NAMES[RPIO.gpio_function(self._number)]
+        return self.GPIO_FUNCTION_NAMES[RPIO.gpio_function(self.number)]
 
     def _set_function(self, value):
         if value != 'input':
             self._pull = 'floating'
         try:
-            RPIO.setup(self._number, self.GPIO_FUNCTIONS[value], self.GPIO_PULL_UPS[self._pull])
+            RPIO.setup(self.number, self.GPIO_FUNCTIONS[value], self.GPIO_PULL_UPS[self._pull])
         except KeyError:
             raise PinInvalidFunction('invalid function "%s" for pin %r' % (value, self))
 
@@ -131,23 +111,23 @@ class RPIOPin(LocalPin):
         if self._pwm:
             return self._duty_cycle
         else:
-            return RPIO.input(self._number)
+            return RPIO.input(self.number)
 
     def _set_state(self, value):
         if not 0 <= value <= 1:
             raise PinInvalidState('invalid state "%s" for pin %r' % (value, self))
         if self._pwm:
-            RPIO.PWM.clear_channel_gpio(0, self._number)
+            RPIO.PWM.clear_channel_gpio(0, self.number)
             if value == 0:
-                RPIO.output(self._number, False)
+                RPIO.output(self.number, False)
             elif value == 1:
-                RPIO.output(self._number, True)
+                RPIO.output(self.number, True)
             else:
-                RPIO.PWM.add_channel_pulse(0, self._number, start=0, width=int(1000 * value))
+                RPIO.PWM.add_channel_pulse(0, self.number, start=0, width=int(1000 * value))
             self._duty_cycle = value
         else:
             try:
-                RPIO.output(self._number, value)
+                RPIO.output(self.number, value)
             except ValueError:
                 raise PinInvalidState('invalid state "%s" for pin %r' % (value, self))
             except RuntimeError:
@@ -159,10 +139,10 @@ class RPIOPin(LocalPin):
     def _set_pull(self, value):
         if self.function != 'input':
             raise PinFixedPull('cannot set pull on non-input pin %r' % self)
-        if value != 'up' and self.PI_INFO.pulled_up('GPIO%d' % self._number):
+        if value != 'up' and self.factory.pi_info.pulled_up('GPIO%d' % self.number):
             raise PinFixedPull('%r has a physical pull-up resistor' % self)
         try:
-            RPIO.setup(self._number, RPIO.IN, self.GPIO_PULL_UPS[value])
+            RPIO.setup(self.number, RPIO.IN, self.GPIO_PULL_UPS[value])
             self._pull = value
         except KeyError:
             raise PinInvalidPull('invalid pull "%s" for pin %r' % (value, self))
@@ -182,10 +162,10 @@ class RPIOPin(LocalPin):
             self._pwm = True
             # Dirty hack to get RPIO's PWM support to setup, but do nothing,
             # for a given GPIO pin
-            RPIO.PWM.add_channel_pulse(0, self._number, start=0, width=0)
+            RPIO.PWM.add_channel_pulse(0, self.number, start=0, width=0)
-            RPIO.PWM.clear_channel_gpio(0, self._number)
+            RPIO.PWM.clear_channel_gpio(0, self.number)
         elif self._pwm and value is None:
-            RPIO.PWM.clear_channel_gpio(0, self._number)
+            RPIO.PWM.clear_channel_gpio(0, self.number)
             self._pwm = False
 
     def _get_bounce(self):
@@ -219,12 +199,12 @@ class RPIOPin(LocalPin):
         if self._when_changed is None and value is not None:
             self._when_changed = value
             RPIO.add_interrupt_callback(
-                self._number,
+                self.number,
                 lambda channel, value: self._when_changed(),
                 self._edges, self.GPIO_PULL_UPS[self._pull], self._bounce)
         elif self._when_changed is not None and value is None:
             try:
-                RPIO.del_interrupt_callback(self._number)
+                RPIO.del_interrupt_callback(self.number)
             except KeyError:
                 # Ignore this exception which occurs during shutdown; this
                 # simply means RPIO's built-in cleanup has already run and

gpiozero/pins/spi.py

@@ -0,0 +1,86 @@
+from __future__ import (
+    unicode_literals,
+    print_function,
+    absolute_import,
+    division,
+    )
+str = type('')
+
+
+import operator
+from threading import RLock
+
+from ..devices import Device, SharedMixin
+from ..input_devices import InputDevice
+from ..output_devices import OutputDevice
+
+
+class SPISoftwareBus(SharedMixin, Device):
+    def __init__(self, clock_pin, mosi_pin, miso_pin):
+        self.lock = None
+        self.clock = None
+        self.mosi = None
+        self.miso = None
+        super(SPISoftwareBus, self).__init__()
+        self.lock = RLock()
+        try:
+            self.clock = OutputDevice(clock_pin, active_high=True)
+            if mosi_pin is not None:
+                self.mosi = OutputDevice(mosi_pin)
+            if miso_pin is not None:
+                self.miso = InputDevice(miso_pin)
+        except:
+            self.close()
+            raise
+
+    def close(self):
+        super(SPISoftwareBus, self).close()
+        if self.lock:
+            with self.lock:
+                if self.miso is not None:
+                    self.miso.close()
+                    self.miso = None
+                if self.mosi is not None:
+                    self.mosi.close()
+                    self.mosi = None
+                if self.clock is not None:
+                    self.clock.close()
+                    self.clock = None
+            self.lock = None
+
+    @property
+    def closed(self):
+        return self.lock is None
+
+    @classmethod
+    def _shared_key(cls, clock_pin, mosi_pin, miso_pin):
+        return (clock_pin, mosi_pin, miso_pin)
+
+    def transfer(self, data, clock_phase=False, lsb_first=False, bits_per_word=8):
+        """
+        Writes data (a list of integer words where each word is assumed to have
+        :attr:`bits_per_word` bits or less) to the SPI interface, and reads an
+        equivalent number of words, returning them as a list of integers.
+        """
+        result = []
+        with self.lock:
+            shift = operator.lshift if lsb_first else operator.rshift
+            for write_word in data:
+                mask = 1 if lsb_first else 1 << (bits_per_word - 1)
+                read_word = 0
+                for _ in range(bits_per_word):
+                    if self.mosi is not None:
+                        self.mosi.value = bool(write_word & mask)
+                    self.clock.on()
+                    if self.miso is not None and not clock_phase:
+                        if self.miso.value:
+                            read_word |= mask
+                    self.clock.off()
+                    if self.miso is not None and clock_phase:
+                        if self.miso.value:
+                            read_word |= mask
+                    mask = shift(mask, 1)
+                result.append(read_word)
+        return result
+
+

gpiozero/spi.py

@@ -1,419 +0,0 @@
-from __future__ import (
-    unicode_literals,
-    print_function,
-    absolute_import,
-    division,
-    )
-str = type('')
-
-
-import warnings
-import operator
-from threading import RLock
-
-try:
-    from spidev import SpiDev
-except ImportError:
-    SpiDev = None
-
-from .devices import Device, SharedMixin, _PINS, _PINS_LOCK
-from .input_devices import InputDevice
-from .output_devices import OutputDevice
-from .exc import SPIBadArgs, SPISoftwareFallback, GPIOPinInUse, DeviceClosed
-
-
-class SPIHardwareInterface(Device):
-    def __init__(self, port, device):
-        self._device = None
-        super(SPIHardwareInterface, self).__init__()
-        # XXX How can we detect conflicts with existing GPIO instances? This
-        # isn't ideal ... in fact, it's downright crap and doesn't guard
-        # against conflicts created *after* this instance, but it's all I can
-        # come up with right now ...
-        conflicts = (11, 10, 9, (8, 7)[device])
-        with _PINS_LOCK:
-            for pin in _PINS:
-                if pin.number in conflicts:
-                    raise GPIOPinInUse(
-                        'pin %r is already in use by another gpiozero object' % pin
-                    )
-        self._device_num = device
-        self._device = SpiDev()
-        self._device.open(port, device)
-        self._device.max_speed_hz = 500000
-
-    def close(self):
-        if self._device:
-            try:
-                self._device.close()
-            finally:
-                self._device = None
-        super(SPIHardwareInterface, self).close()
-
-    @property
-    def closed(self):
-        return self._device is None
-
-    def __repr__(self):
-        try:
-            self._check_open()
-            return (
-                "hardware SPI on clock_pin=11, mosi_pin=10, miso_pin=9, "
-                "select_pin=%d" % (
-                    8 if self._device_num == 0 else 7))
-        except DeviceClosed:
-            return "hardware SPI closed"
-
-    def read(self, n):
-        return self.transfer((0,) * n)
-
-    def write(self, data):
-        return len(self.transfer(data))
-
-    def transfer(self, data):
-        """
-        Writes data (a list of integer words where each word is assumed to have
-        :attr:`bits_per_word` bits or less) to the SPI interface, and reads an
-        equivalent number of words, returning them as a list of integers.
-        """
-        return self._device.xfer2(data)
-
-    def _get_clock_mode(self):
-        return self._device.mode
-
-    def _set_clock_mode(self, value):
-        self._device.mode = value
-
-    def _get_clock_polarity(self):
-        return bool(self.clock_mode & 2)
-
-    def _set_clock_polarity(self, value):
-        self.clock_mode = self.clock_mode & (~2) | (bool(value) << 1)
-
-    def _get_clock_phase(self):
-        return bool(self.clock_mode & 1)
-
-    def _set_clock_phase(self, value):
-        self.clock_mode = self.clock_mode & (~1) | bool(value)
-
-    def _get_lsb_first(self):
-        return self._device.lsbfirst
-
-    def _set_lsb_first(self, value):
-        self._device.lsbfirst = bool(value)
-
-    def _get_select_high(self):
-        return self._device.cshigh
-
-    def _set_select_high(self, value):
-        self._device.cshigh = bool(value)
-
-    def _get_bits_per_word(self):
-        return self._device.bits_per_word
-
-    def _set_bits_per_word(self, value):
-        self._device.bits_per_word = value
-
-    clock_polarity = property(_get_clock_polarity, _set_clock_polarity)
-    clock_phase = property(_get_clock_phase, _set_clock_phase)
-    clock_mode = property(_get_clock_mode, _set_clock_mode)
-    lsb_first = property(_get_lsb_first, _set_lsb_first)
-    select_high = property(_get_select_high, _set_select_high)
-    bits_per_word = property(_get_bits_per_word, _set_bits_per_word)
-
-
-class SPISoftwareBus(SharedMixin, Device):
-    def __init__(self, clock_pin, mosi_pin, miso_pin):
-        self.lock = None
-        self.clock = None
-        self.mosi = None
-        self.miso = None
-        super(SPISoftwareBus, self).__init__()
-        self.lock = RLock()
-        try:
-            self.clock = OutputDevice(clock_pin, active_high=True)
-            if mosi_pin is not None:
-                self.mosi = OutputDevice(mosi_pin)
-            if miso_pin is not None:
-                self.miso = InputDevice(miso_pin)
-        except:
-            self.close()
-            raise
-
-    def close(self):
-        super(SPISoftwareBus, self).close()
-        if self.lock:
-            with self.lock:
-                if self.miso is not None:
-                    self.miso.close()
-                    self.miso = None
-                if self.mosi is not None:
-                    self.mosi.close()
-                    self.mosi = None
-                if self.clock is not None:
-                    self.clock.close()
-                    self.clock = None
-            self.lock = None
-
-    @property
-    def closed(self):
-        return self.lock is None
-
-    @classmethod
-    def _shared_key(cls, clock_pin, mosi_pin, miso_pin):
-        return (clock_pin, mosi_pin, miso_pin)
-
-    def transfer(self, data, clock_phase=False, lsb_first=False, bits_per_word=8):
-        """
-        Writes data (a list of integer words where each word is assumed to have
-        :attr:`bits_per_word` bits or less) to the SPI interface, and reads an
-        equivalent number of words, returning them as a list of integers.
-        """
-        result = []
-        with self.lock:
-            shift = operator.lshift if lsb_first else operator.rshift
-            for write_word in data:
-                mask = 1 if lsb_first else 1 << (bits_per_word - 1)
-                read_word = 0
-                for _ in range(bits_per_word):
-                    if self.mosi is not None:
-                        self.mosi.value = bool(write_word & mask)
-                    self.clock.on()
-                    if self.miso is not None and not clock_phase:
-                        if self.miso.value:
-                            read_word |= mask
-                    self.clock.off()
-                    if self.miso is not None and clock_phase:
-                        if self.miso.value:
-                            read_word |= mask
-                    mask = shift(mask, 1)
-                result.append(read_word)
-        return result
-
-
-class SPISoftwareInterface(OutputDevice):
-    def __init__(self, clock_pin, mosi_pin, miso_pin, select_pin):
-        self._bus = None
-        super(SPISoftwareInterface, self).__init__(select_pin, active_high=False)
-        try:
-            self._clock_phase = False
-            self._lsb_first = False
-            self._bits_per_word = 8
-            self._bus = SPISoftwareBus(clock_pin, mosi_pin, miso_pin)
-        except:
-            self.close()
-            raise
-
-    def close(self):
-        if self._bus:
-            self._bus.close()
-            self._bus = None
-        super(SPISoftwareInterface, self).close()
-
-    def __repr__(self):
-        try:
-            self._check_open()
-            return (
-                "software SPI on clock_pin=%d, mosi_pin=%d, miso_pin=%d, "
-                "select_pin=%d" % (
-                    self._bus.clock.pin.number,
-                    self._bus.mosi.pin.number,
-                    self._bus.miso.pin.number,
-                    self.pin.number))
-        except DeviceClosed:
-            return "software SPI closed"
-
-    def read(self, n):
-        return self.transfer((0,) * n)
-
-    def write(self, data):
-        return len(self.transfer(data))
-
-    def transfer(self, data):
-        with self._bus.lock:
-            self.on()
-            try:
-                return self._bus.transfer(
-                    data, self._clock_phase, self._lsb_first, self._bits_per_word)
-            finally:
-                self.off()
-
-    def _get_clock_mode(self):
-        return (self.clock_polarity << 1) | self.clock_phase
-
-    def _set_clock_mode(self, value):
-        value = int(value)
-        if not 0 <= value <= 3:
-            raise ValueError('clock_mode must be a value between 0 and 3 inclusive')
-        self.clock_polarity = bool(value & 2)
-        self.clock_phase = bool(value & 1)
-
-    def _get_clock_polarity(self):
-        with self._bus.lock:
-            return not self._bus.clock.active_high
-
-    def _set_clock_polarity(self, value):
-        with self._bus.lock:
-            self._bus.clock.active_high = not value
-            self._bus.clock.off()
-
-    def _get_clock_phase(self):
-        return self._clock_phase
-
-    def _set_clock_phase(self, value):
-        self._clock_phase = bool(value)
-
-    def _get_lsb_first(self):
-        return self._lsb_first
-
-    def _set_lsb_first(self, value):
-        self._lsb_first = bool(value)
-
-    def _get_bits_per_word(self):
-        return self._bits_per_word
-
-    def _set_bits_per_word(self, value):
-        if value < 1:
-            raise ValueError('bits_per_word must be positive')
-        self._bits_per_word = int(value)
-
-    def _get_select_high(self):
-        return self.active_high
-
-    def _set_select_high(self, value):
-        with self._bus.lock:
-            self.active_high = value
-            self.off()
-
-    clock_polarity = property(_get_clock_polarity, _set_clock_polarity)
-    clock_phase = property(_get_clock_phase, _set_clock_phase)
-    clock_mode = property(_get_clock_mode, _set_clock_mode)
-    lsb_first = property(_get_lsb_first, _set_lsb_first)
-    bits_per_word = property(_get_bits_per_word, _set_bits_per_word)
-    select_high = property(_get_select_high, _set_select_high)
-
-
-class SharedSPIHardwareInterface(SharedMixin, SPIHardwareInterface):
-    @classmethod
-    def _shared_key(cls, port, device):
-        return (port, device)
-
-
-class SharedSPISoftwareInterface(SharedMixin, SPISoftwareInterface):
-    @classmethod
-    def _shared_key(cls, clock_pin, mosi_pin, miso_pin, select_pin):
-        return (clock_pin, mosi_pin, miso_pin, select_pin)
-
-
-def extract_spi_args(**kwargs):
-    """
-    Given a set of keyword arguments, splits it into those relevant to SPI
-    implementations and all the rest. SPI arguments are augmented with defaults
-    and converted into the pin format (from the port/device format) if
-    necessary.
-
-    Returns a tuple of ``(spi_args, other_args)``.
-    """
-    pin_defaults = {
-        'clock_pin': 11,
-        'mosi_pin': 10,
-        'miso_pin': 9,
-        'select_pin': 8,
-        }
-    dev_defaults = {
-        'port': 0,
-        'device': 0,
-        }
-    spi_args = {
-        key: value for (key, value) in kwargs.items()
-        if key in pin_defaults or key in dev_defaults
-        }
-    kwargs = {
-        key: value for (key, value) in kwargs.items()
-        if key not in spi_args
-        }
-    if not spi_args:
-        spi_args = pin_defaults
-    elif set(spi_args) <= set(pin_defaults):
-        spi_args = {
-            key: spi_args.get(key, default)
-            for key, default in pin_defaults.items()
-            }
-    elif set(spi_args) <= set(dev_defaults):
-        spi_args = {
-            key: spi_args.get(key, default)
-            for key, default in dev_defaults.items()
-            }
-        if spi_args['port'] != 0:
-            raise SPIBadArgs('port 0 is the only valid SPI port')
-        if spi_args['device'] not in (0, 1):
-            raise SPIBadArgs('device must be 0 or 1')
-        spi_args = {
-            key: value if key != 'select_pin' else (8, 7)[spi_args['device']]
-            for key, value in pin_defaults.items()
-            }
-    else:
-        raise SPIBadArgs(
-            'you must either specify port and device, or clock_pin, mosi_pin, '
-            'miso_pin, and select_pin; combinations of the two schemes (e.g. '
-            'port and clock_pin) are not permitted')
-    return spi_args, kwargs
-
-
-def SPI(**spi_args):
-    """
-    Returns an SPI interface, for the specified SPI *port* and *device*, or for
-    the specified pins (*clock_pin*, *mosi_pin*, *miso_pin*, and *select_pin*).
-    Only one of the schemes can be used; attempting to mix *port* and *device*
-    with pin numbers will raise :exc:`SPIBadArgs`.
-
-    If the pins specified match the hardware SPI pins (clock on GPIO11, MOSI on
-    GPIO10, MISO on GPIO9, and chip select on GPIO8 or GPIO7), and the spidev
-    module can be imported, a :class:`SPIHardwareInterface` instance will be
-    returned. Otherwise, a :class:`SPISoftwareInterface` will be returned which
-    will use simple bit-banging to communicate.
-
-    Both interfaces have the same API, support clock polarity and phase
-    attributes, and can handle half and full duplex communications, but the
-    hardware interface is significantly faster (though for many things this
-    doesn't matter).
-
-    Finally, the *shared* keyword argument specifies whether the resulting
-    SPI interface can be repeatedly created and used by multiple devices
-    (useful with multi-channel devices like numerous ADCs).
-    """
-    spi_args, kwargs = extract_spi_args(**spi_args)
-    shared = kwargs.pop('shared', False)
-    if kwargs:
-        raise SPIBadArgs(
-            'unrecognized keyword argument %s' % kwargs.popitem()[0])
-    if all((
-            spi_args['clock_pin'] == 11,
-            spi_args['mosi_pin'] == 10,
-            spi_args['miso_pin'] == 9,
-            spi_args['select_pin'] in (7, 8),
-            )):
-        if SpiDev is None:
-            warnings.warn(
-                SPISoftwareFallback(
-                    'failed to import spidev, falling back to software SPI'))
-        else:
-            try:
-                hardware_spi_args = {
-                    'port': 0,
-                    'device': {8: 0, 7: 1}[spi_args['select_pin']],
-                    }
-                if shared:
-                    return SharedSPIHardwareInterface(**hardware_spi_args)
-                else:
-                    return SPIHardwareInterface(**hardware_spi_args)
-            except Exception as e:
-                warnings.warn(
-                    SPISoftwareFallback(
-                        'failed to initialize hardware SPI, falling back to '
-                        'software (error was: %s)' % str(e)))
-    if shared:
-        return SharedSPISoftwareInterface(**spi_args)
-    else:
-        return SPISoftwareInterface(**spi_args)
-

gpiozero/spi_devices.py

@@ -16,7 +16,6 @@ except ImportError:
 
 from .exc import DeviceClosed, SPIBadChannel
 from .devices import Device
-from .spi import SPI
 
 
 class SPIDevice(Device):
@@ -28,13 +27,12 @@ class SPIDevice(Device):
     specified with the constructor.
     """
     def __init__(self, **spi_args):
-        self._spi = SPI(**spi_args)
+        self._spi = self._pin_factory.spi(**spi_args)
 
     def close(self):
         if self._spi:
-            s = self._spi
+            self._spi.close()
             self._spi = None
-            s.close()
         super(SPIDevice, self).close()
 
     @property

setup.py

@@ -68,12 +68,12 @@ if sys.version_info[:2] == (3, 2):
 
 __entry_points__ = {
     'gpiozero_pin_factories': [
-        'PiGPIOPin  = gpiozero.pins.pigpiod:PiGPIOPin',
+        'pigpio  = gpiozero.pins.pigpiod:PiGPIOFactory',
-        'RPiGPIOPin = gpiozero.pins.rpigpio:RPiGPIOPin',
+        'rpigpio = gpiozero.pins.rpigpio:RPiGPIOFactory',
-        'RPIOPin    = gpiozero.pins.rpio:RPIOPin',
+        'rpio    = gpiozero.pins.rpio:RPIOFactory',
-        'NativePin  = gpiozero.pins.native:NativePin',
+        'native  = gpiozero.pins.native:NativeFactory',
-        'MockPin    = gpiozero.pins.mock:MockPin',
+        'mock    = gpiozero.pins.mock:MockFactory',
-        'MockPWMPin = gpiozero.pins.mock:MockPWMPin',
+        'mockpwm = gpiozero.pins.mock:MockPWMFactory',
     ],
     'console_scripts': [
         'pinout = gpiozero.cli.pinout:main',

tests/conftest.py

@@ -0,0 +1,10 @@
+from __future__ import (
+    unicode_literals,
+    print_function,
+    absolute_import,
+    division,
+    )
+str = type('')
+
+import os
+os.environ['GPIOZERO_PIN_FACTORY'] = 'mock'

tests/test_boards.py

@@ -11,26 +11,39 @@ import sys
 import pytest
 from time import sleep
 
-from gpiozero.pins.mock import MockPin, MockPWMPin
 from gpiozero import *
+from gpiozero.pins.mock import MockPWMPin, MockPin
 
 
 def setup_function(function):
-    import gpiozero.devices
     # dirty, but it does the job
-    if function.__name__ in ('test_robot', 'test_ryanteck_robot', 'test_camjam_kit_robot', 'test_led_borg', 'test_snow_pi_initial_value_pwm'):
+    Device._pin_factory.pin_class = MockPWMPin if function.__name__ in (
-        gpiozero.devices.pin_factory = MockPWMPin
+        'test_robot',
-    else:
+        'test_ryanteck_robot',
-        gpiozero.devices.pin_factory = MockPin
+        'test_camjam_kit_robot',
+        'test_led_borg',
+        'test_led_board_pwm_value',
+        'test_led_board_pwm_bad_value',
+        'test_snow_pi_initial_value_pwm',
+        'test_led_board_pwm_initial_value',
+        'test_led_board_pwm_bad_initial_value',
+        'test_led_board_fade_background',
+        'test_led_bar_graph_pwm_value',
+        'test_led_bar_graph_pwm_initial_value',
+        ) else MockPin
 
 def teardown_function(function):
-    MockPin.clear_pins()
+    Device._pin_factory.reset()
+
+def teardown_module(module):
+    # make sure we reset the default
+    Device._pin_factory.pwm = False
 
 
 def test_composite_output_on_off():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with CompositeOutputDevice(OutputDevice(pin1), OutputDevice(pin2), foo=OutputDevice(pin3)) as device:
         device.on()
         assert all((pin1.state, pin2.state, pin3.state))
@@ -38,9 +51,9 @@ def test_composite_output_on_off():
         assert not any((pin1.state, pin2.state, pin3.state))
 
 def test_composite_output_toggle():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with CompositeOutputDevice(OutputDevice(pin1), OutputDevice(pin2), foo=OutputDevice(pin3)) as device:
         device.toggle()
         assert all((pin1.state, pin2.state, pin3.state))
@@ -51,9 +64,9 @@ def test_composite_output_toggle():
         assert not pin3.state
 
 def test_composite_output_value():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with CompositeOutputDevice(OutputDevice(pin1), OutputDevice(pin2), foo=OutputDevice(pin3)) as device:
         assert device.value == (0, 0, 0)
         device.toggle()
@@ -64,9 +77,9 @@ def test_composite_output_value():
         assert device[2].is_active
 
 def test_led_board_on_off():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, pin2, foo=pin3) as board:
         assert isinstance(board[0], LED)
         assert isinstance(board[1], LED)
@@ -121,9 +134,9 @@ def test_led_board_on_off():
         assert pin3.state
 
 def test_led_board_active_low():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, pin2, foo=pin3, active_high=False) as board:
         assert not board.active_high
         assert not board[0].active_high
@@ -145,9 +158,9 @@ def test_led_board_active_low():
         assert not pin3.state
 
 def test_led_board_value():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, pin2, foo=pin3) as board:
         assert board.value == (0, 0, 0)
         board.value = (0, 1, 0)
@@ -156,9 +169,9 @@ def test_led_board_value():
         assert board.value == (1, 0, 1)
 
 def test_led_board_pwm_value():
-    pin1 = MockPWMPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPWMPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPWMPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, pin2, foo=pin3, pwm=True) as board:
         assert board.value == (0, 0, 0)
         board.value = (0, 1, 0)
@@ -167,9 +180,9 @@ def test_led_board_pwm_value():
         assert board.value == (0.5, 0, 0.75)
 
 def test_led_board_pwm_bad_value():
-    pin1 = MockPWMPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPWMPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPWMPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, pin2, foo=pin3, pwm=True) as board:
         with pytest.raises(ValueError):
             board.value = (-1, 0, 0)
@@ -177,18 +190,18 @@ def test_led_board_pwm_bad_value():
             board.value = (0, 2, 0)
 
 def test_led_board_initial_value():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, pin2, foo=pin3, initial_value=0) as board:
         assert board.value == (0, 0, 0)
     with LEDBoard(pin1, pin2, foo=pin3, initial_value=1) as board:
         assert board.value == (1, 1, 1)
 
 def test_led_board_pwm_initial_value():
-    pin1 = MockPWMPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPWMPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPWMPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, pin2, foo=pin3, pwm=True, initial_value=0) as board:
         assert board.value == (0, 0, 0)
     with LEDBoard(pin1, pin2, foo=pin3, pwm=True, initial_value=1) as board:
@@ -197,18 +210,18 @@ def test_led_board_pwm_initial_value():
         assert board.value == (0.5, 0.5, 0.5)
 
 def test_led_board_pwm_bad_initial_value():
-    pin1 = MockPWMPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPWMPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPWMPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with pytest.raises(ValueError):
         LEDBoard(pin1, pin2, foo=pin3, pwm=True, initial_value=-1)
     with pytest.raises(ValueError):
         LEDBoard(pin1, pin2, foo=pin3, pwm=True, initial_value=2)
 
 def test_led_board_nested():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, LEDBoard(pin2, pin3)) as board:
         assert list(led.pin for led in board.leds) == [pin1, pin2, pin3]
         assert board.value == (0, (0, 0))
@@ -218,9 +231,9 @@ def test_led_board_nested():
         assert pin3.state
 
 def test_led_board_bad_blink():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, LEDBoard(pin2, pin3)) as board:
         with pytest.raises(ValueError):
             board.blink(fade_in_time=1, fade_out_time=1)
@@ -232,9 +245,9 @@ def test_led_board_bad_blink():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_led_board_blink_background():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, LEDBoard(pin2, pin3)) as board:
         board.blink(0.1, 0.1, n=2)
         board._blink_thread.join() # naughty, but ensures no arbitrary waits in the test
@@ -252,9 +265,9 @@ def test_led_board_blink_background():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_led_board_blink_foreground():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, LEDBoard(pin2, pin3)) as board:
         board.blink(0.1, 0.1, n=2, background=False)
         test = [
@@ -271,9 +284,9 @@ def test_led_board_blink_foreground():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_led_board_blink_control():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, LEDBoard(pin2, pin3)) as board:
         board.blink(0.1, 0.1, n=2)
         # make sure the blink thread's started
@@ -296,9 +309,9 @@ def test_led_board_blink_control():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_led_board_blink_take_over():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, LEDBoard(pin2, pin3)) as board:
         board[1].blink(0.1, 0.1, n=2)
         board.blink(0.1, 0.1, n=2) # immediately take over blinking
@@ -318,9 +331,9 @@ def test_led_board_blink_take_over():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_led_board_blink_control_all():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, LEDBoard(pin2, pin3)) as board:
         board.blink(0.1, 0.1, n=2)
         # make sure the blink thread's started
@@ -340,9 +353,9 @@ def test_led_board_blink_control_all():
         pin3.assert_states_and_times(test)
 
 def test_led_board_blink_interrupt_on():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, LEDBoard(pin2, pin3)) as board:
         board.blink(1, 0.1)
         sleep(0.2)
@@ -352,9 +365,9 @@ def test_led_board_blink_interrupt_on():
         pin3.assert_states([False, True, False])
 
 def test_led_board_blink_interrupt_off():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, LEDBoard(pin2, pin3)) as board:
         board.blink(0.1, 1)
         sleep(0.2)
@@ -366,9 +379,9 @@ def test_led_board_blink_interrupt_off():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_led_board_fade_background():
-    pin1 = MockPWMPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPWMPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPWMPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBoard(pin1, LEDBoard(pin2, pin3, pwm=True), pwm=True) as board:
         board.blink(0, 0, 0.2, 0.2, n=2)
         board._blink_thread.join()
@@ -400,9 +413,9 @@ def test_led_board_fade_background():
         pin3.assert_states_and_times(test)
 
 def test_led_bar_graph_value():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBarGraph(pin1, pin2, pin3) as graph:
         assert isinstance(graph[0], LED)
         assert isinstance(graph[1], LED)
@@ -433,9 +446,9 @@ def test_led_bar_graph_value():
         assert graph.value == -2/3
 
 def test_led_bar_graph_active_low():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBarGraph(pin1, pin2, pin3, active_high=False) as graph:
         assert not graph.active_high
         assert not graph[0].active_high
@@ -455,9 +468,9 @@ def test_led_bar_graph_active_low():
         assert not pin3.state and pin1.state and pin2.state
 
 def test_led_bar_graph_pwm_value():
-    pin1 = MockPWMPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPWMPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPWMPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBarGraph(pin1, pin2, pin3, pwm=True) as graph:
         assert isinstance(graph[0], PWMLED)
         assert isinstance(graph[1], PWMLED)
@@ -482,9 +495,9 @@ def test_led_bar_graph_pwm_value():
         assert graph.value == -1/2
 
 def test_led_bar_graph_bad_value():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBarGraph(pin1, pin2, pin3) as graph:
         with pytest.raises(ValueError):
             graph.value = -2
@@ -492,9 +505,9 @@ def test_led_bar_graph_bad_value():
             graph.value = 2
 
 def test_led_bar_graph_bad_init():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with pytest.raises(TypeError):
         LEDBarGraph(pin1, pin2, foo=pin3)
     with pytest.raises(ValueError):
@@ -503,9 +516,9 @@ def test_led_bar_graph_bad_init():
         LEDBarGraph(pin1, pin2, pin3, initial_value=2)
 
 def test_led_bar_graph_initial_value():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBarGraph(pin1, pin2, pin3, initial_value=1/3) as graph:
         assert graph.value == 1/3
         assert pin1.state and not (pin2.state or pin3.state)
@@ -514,9 +527,9 @@ def test_led_bar_graph_initial_value():
         assert pin3.state and not (pin1.state or pin2.state)
 
 def test_led_bar_graph_pwm_initial_value():
-    pin1 = MockPWMPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPWMPin(3)
+    pin2 = Device._pin_factory.pin(3)
-    pin3 = MockPWMPin(4)
+    pin3 = Device._pin_factory.pin(4)
     with LEDBarGraph(pin1, pin2, pin3, pwm=True, initial_value=0.5) as graph:
         assert graph.value == 0.5
         assert (pin1.state, pin2.state, pin3.state) == (1, 0.5, 0)
@@ -525,17 +538,17 @@ def test_led_bar_graph_pwm_initial_value():
         assert (pin1.state, pin2.state, pin3.state) == (0, 0.5, 1)
 
 def test_led_borg():
-    pins = [MockPWMPin(n) for n in (17, 27, 22)]
+    pins = [Device._pin_factory.pin(n) for n in (17, 27, 22)]
     with LedBorg() as board:
         assert [device.pin for device in board._leds] == pins
 
 def test_pi_liter():
-    pins = [MockPin(n) for n in (4, 17, 27, 18, 22, 23, 24, 25)]
+    pins = [Device._pin_factory.pin(n) for n in (4, 17, 27, 18, 22, 23, 24, 25)]
     with PiLiter() as board:
         assert [device.pin for device in board] == pins
 
 def test_pi_liter_graph():
-    pins = [MockPin(n) for n in (4, 17, 27, 18, 22, 23, 24, 25)]
+    pins = [Device._pin_factory.pin(n) for n in (4, 17, 27, 18, 22, 23, 24, 25)]
     with PiLiterBarGraph() as board:
         board.value = 0.5
         assert [pin.state for pin in pins] == [1, 1, 1, 1, 0, 0, 0, 0]
@@ -543,9 +556,9 @@ def test_pi_liter_graph():
         assert board.value == 5/8
 
 def test_traffic_lights():
-    red_pin = MockPin(2)
+    red_pin = Device._pin_factory.pin(2)
-    amber_pin = MockPin(3)
+    amber_pin = Device._pin_factory.pin(3)
-    green_pin = MockPin(4)
+    green_pin = Device._pin_factory.pin(4)
     with TrafficLights(red_pin, amber_pin, green_pin) as board:
         board.red.on()
         assert board.red.value
@@ -574,15 +587,15 @@ def test_traffic_lights():
 def test_traffic_lights_bad_init():
     with pytest.raises(ValueError):
         TrafficLights()
-    red_pin = MockPin(2)
+    red_pin = Device._pin_factory.pin(2)
-    amber_pin = MockPin(3)
+    amber_pin = Device._pin_factory.pin(3)
-    green_pin = MockPin(4)
+    green_pin = Device._pin_factory.pin(4)
-    yellow_pin = MockPin(5)
+    yellow_pin = Device._pin_factory.pin(5)
     with pytest.raises(ValueError):
         TrafficLights(red=red_pin, amber=amber_pin, yellow=yellow_pin, green=green_pin)
 
 def test_pi_traffic():
-    pins = [MockPin(n) for n in (9, 10, 11)]
+    pins = [Device._pin_factory.pin(n) for n in (9, 10, 11)]
     with PiTraffic() as board:
         assert [device.pin for device in board] == pins
 
@@ -591,27 +604,27 @@ def test_pi_stop():
         PiStop()
     with pytest.raises(ValueError):
         PiStop('E')
-    pins_a = [MockPin(n) for n in (7, 8, 25)]
+    pins_a = [Device._pin_factory.pin(n) for n in (7, 8, 25)]
     with PiStop('A') as board:
         assert [device.pin for device in board] == pins_a
-    pins_aplus = [MockPin(n) for n in (21, 20, 16)]
+    pins_aplus = [Device._pin_factory.pin(n) for n in (21, 20, 16)]
     with PiStop('A+') as board:
         assert [device.pin for device in board] == pins_aplus
-    pins_b = [MockPin(n) for n in (10, 9, 11)]
+    pins_b = [Device._pin_factory.pin(n) for n in (10, 9, 11)]
     with PiStop('B') as board:
         assert [device.pin for device in board] == pins_b
-    pins_bplus = [MockPin(n) for n in (13, 19, 26)]
+    pins_bplus = [Device._pin_factory.pin(n) for n in (13, 19, 26)]
     with PiStop('B+') as board:
         assert [device.pin for device in board] == pins_bplus
-    pins_c = [MockPin(n) for n in (18, 15, 14)]
+    pins_c = [Device._pin_factory.pin(n) for n in (18, 15, 14)]
     with PiStop('C') as board:
         assert [device.pin for device in board] == pins_c
-    pins_d = [MockPin(n) for n in (2, 3, 4)]
+    pins_d = [Device._pin_factory.pin(n) for n in (2, 3, 4)]
     with PiStop('D') as board:
         assert [device.pin for device in board] == pins_d
 
 def test_snow_pi():
-    pins = [MockPin(n) for n in (23, 24, 25, 17, 18, 22, 7, 8, 9)]
+    pins = [Device._pin_factory.pin(n) for n in (23, 24, 25, 17, 18, 22, 7, 8, 9)]
     with SnowPi() as board:
         assert [device.pin for device in board.leds] == pins
 
@@ -626,17 +639,17 @@ def test_snow_pi_initial_value():
         assert all(device.pin.state == True for device in board.leds)
 
 def test_snow_pi_initial_value_pwm():
-    pins = [MockPWMPin(n) for n in (23, 24, 25, 17, 18, 22, 7, 8, 9)]
+    pins = [Device._pin_factory.pin(n) for n in (23, 24, 25, 17, 18, 22, 7, 8, 9)]
     with SnowPi(pwm=True, initial_value=0.5) as board:
         assert [device.pin for device in board.leds] == pins
         assert all(device.pin.state == 0.5 for device in board.leds)
 
 def test_traffic_lights_buzzer():
-    red_pin = MockPin(2)
+    red_pin = Device._pin_factory.pin(2)
-    amber_pin = MockPin(3)
+    amber_pin = Device._pin_factory.pin(3)
-    green_pin = MockPin(4)
+    green_pin = Device._pin_factory.pin(4)
-    buzzer_pin = MockPin(5)
+    buzzer_pin = Device._pin_factory.pin(5)
-    button_pin = MockPin(6)
+    button_pin = Device._pin_factory.pin(6)
     with TrafficLightsBuzzer(
             TrafficLights(red_pin, amber_pin, green_pin),
             Buzzer(buzzer_pin),
@@ -651,17 +664,17 @@ def test_traffic_lights_buzzer():
         assert board.button.is_active
 
 def test_fish_dish():
-    pins = [MockPin(n) for n in (9, 22, 4, 8, 7)]
+    pins = [Device._pin_factory.pin(n) for n in (9, 22, 4, 8, 7)]
     with FishDish() as board:
         assert [led.pin for led in board.lights] + [board.buzzer.pin, board.button.pin] == pins
 
 def test_traffic_hat():
-    pins = [MockPin(n) for n in (24, 23, 22, 5, 25)]
+    pins = [Device._pin_factory.pin(n) for n in (24, 23, 22, 5, 25)]
     with TrafficHat() as board:
         assert [led.pin for led in board.lights] + [board.buzzer.pin, board.button.pin] == pins
 
 def test_robot():
-    pins = [MockPWMPin(n) for n in (2, 3, 4, 5)]
+    pins = [Device._pin_factory.pin(n) for n in (2, 3, 4, 5)]
     with Robot((2, 3), (4, 5)) as robot:
         assert (
             [device.pin for device in robot.left_motor] +
@@ -696,12 +709,12 @@ def test_robot():
         assert robot.value == (0, -0.5)
 
 def test_ryanteck_robot():
-    pins = [MockPWMPin(n) for n in (17, 18, 22, 23)]
+    pins = [Device._pin_factory.pin(n) for n in (17, 18, 22, 23)]
     with RyanteckRobot() as board:
         assert [device.pin for motor in board for device in motor] == pins
 
 def test_camjam_kit_robot():
-    pins = [MockPWMPin(n) for n in (9, 10, 7, 8)]
+    pins = [Device._pin_factory.pin(n) for n in (9, 10, 7, 8)]
     with CamJamKitRobot() as board:
         assert [device.pin for motor in board for device in motor] == pins
 
@@ -714,7 +727,7 @@ def test_energenie_bad_init():
         Energenie(5)
 
 def test_energenie():
-    pins = [MockPin(n) for n in (17, 22, 23, 27, 24, 25)]
+    pins = [Device._pin_factory.pin(n) for n in (17, 22, 23, 27, 24, 25)]
     with Energenie(1, initial_value=True) as device1, \
             Energenie(2, initial_value=False) as device2:
         assert repr(device1) == '<gpiozero.Energenie object on socket 1>'

tests/test_devices.py

@@ -6,86 +6,87 @@ from __future__ import (
     )
 str = type('')
 
+import warnings
 
 import pytest
 
-from gpiozero.pins.mock import MockPin
 from gpiozero import *
 
 
 def teardown_function(function):
-    MockPin.clear_pins()
+    Device._pin_factory.reset()
+
 
 # TODO add more devices tests!
 
-def test_device_no_pin():
+def test_device_bad_pin():
     with pytest.raises(GPIOPinMissing):
         device = GPIODevice()
+    with pytest.raises(PinInvalidPin):
+        device = GPIODevice(60)
+
+def test_device_non_physical():
+    with warnings.catch_warnings(record=True) as w:
+        device = GPIODevice(37)
+        assert len(w) == 1
+        assert w[0].category == PinNonPhysical
 
 def test_device_init():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with GPIODevice(pin) as device:
         assert not device.closed
         assert device.pin == pin
 
 def test_device_init_twice_same_pin():
-    pin = MockPin(2)
+    with GPIODevice(2) as device:
-    with GPIODevice(pin) as device:
         with pytest.raises(GPIOPinInUse):
-            device2 = GPIODevice(pin)
+            GPIODevice(2)
 
 def test_device_init_twice_different_pin():
-    pin = MockPin(2)
+    with GPIODevice(2) as device:
-    pin2 = MockPin(3)
+        with GPIODevice(3) as device2:
-    with GPIODevice(pin) as device:
-        with GPIODevice(pin2) as device2:
             pass
 
 def test_device_close():
-    pin = MockPin(2)
+    device = GPIODevice(2)
-    device = GPIODevice(pin)
     device.close()
     assert device.closed
     assert device.pin is None
 
 def test_device_reopen_same_pin():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     device = GPIODevice(pin)
     device.close()
     device2 = GPIODevice(pin)
     assert not device2.closed
-    assert device2.pin == pin
+    assert device2.pin is pin
     assert device.closed
     assert device.pin is None
     device2.close()
 
 def test_device_repr():
-    pin = MockPin(2)
+    with GPIODevice(2) as device:
-    with GPIODevice(pin) as device:
+        assert repr(device) == '<gpiozero.GPIODevice object on pin %s, is_active=False>' % device.pin
-        assert repr(device) == '<gpiozero.GPIODevice object on pin %s, is_active=False>' % pin
 
 def test_device_repr_after_close():
-    pin = MockPin(2)
+    device = GPIODevice(2)
-    device = GPIODevice(pin)
     device.close()
     assert repr(device) == '<gpiozero.GPIODevice object closed>'
 
 def test_device_unknown_attr():
-    pin = MockPin(2)
+    with GPIODevice(2) as device:
-    with GPIODevice(pin) as device:
         with pytest.raises(AttributeError):
             device.foo = 1
 
 def test_device_context_manager():
-    pin = MockPin(2)
+    with GPIODevice(2) as device:
-    with GPIODevice(pin) as device:
         assert not device.closed
     assert device.closed
 
 def test_composite_device_sequence():
     with CompositeDevice(
-            InputDevice(MockPin(2)),
+            InputDevice(2),
-            InputDevice(MockPin(3))
+            InputDevice(3)
             ) as device:
         assert len(device) == 2
         assert device[0].pin.number == 2
@@ -94,8 +95,8 @@ def test_composite_device_sequence():
 
 def test_composite_device_values():
     with CompositeDevice(
-            InputDevice(MockPin(2)),
+            InputDevice(2),
-            InputDevice(MockPin(3))
+            InputDevice(3)
             ) as device:
         assert device.value == (0, 0)
         assert not device.is_active
@@ -105,8 +106,8 @@ def test_composite_device_values():
 
 def test_composite_device_named():
     with CompositeDevice(
-            foo=InputDevice(MockPin(2)),
+            foo=InputDevice(2),
-            bar=InputDevice(MockPin(3)),
+            bar=InputDevice(3),
             _order=('foo', 'bar')
             ) as device:
         assert device.namedtuple._fields == ('foo', 'bar')
@@ -121,13 +122,13 @@ def test_composite_device_bad_init():
     with pytest.raises(ValueError):
         CompositeDevice(2)
     with pytest.raises(ValueError):
-        CompositeDevice(MockPin(2))
+        CompositeDevice(Device._pin_factory.pin(2))
 
 def test_composite_device_read_only():
-    device = CompositeDevice(
+    with CompositeDevice(
-        foo=InputDevice(MockPin(2)),
+        foo=InputDevice(2),
-        bar=InputDevice(MockPin(3))
+        bar=InputDevice(3)
-        )
+        ) as device:
-    with pytest.raises(AttributeError):
+        with pytest.raises(AttributeError):
-        device.foo = 1
+            device.foo = 1
 

tests/test_inputs.py

@@ -12,57 +12,52 @@ import pytest
 from threading import Event
 from functools import partial
 
-from gpiozero.pins.mock import (
+from gpiozero.pins.mock import MockPulledUpPin, MockChargingPin, MockTriggerPin
-    MockPin,
-    MockPulledUpPin,
-    MockChargingPin,
-    MockTriggerPin,
-    )
 from gpiozero import *
 
 
 def teardown_function(function):
-    MockPin.clear_pins()
+    Device._pin_factory.reset()
+
 
 def test_input_initial_values():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with InputDevice(pin, pull_up=True) as device:
         assert pin.function == 'input'
         assert pin.pull == 'up'
         assert device.pull_up
-        device.close()
+    with InputDevice(pin, pull_up=False) as device:
-        device = InputDevice(pin, pull_up=False)
         assert pin.pull == 'down'
         assert not device.pull_up
 
 def test_input_is_active_low():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with InputDevice(pin, pull_up=True) as device:
         pin.drive_high()
         assert not device.is_active
-        assert repr(device) == '<gpiozero.InputDevice object on pin MOCK2, pull_up=True, is_active=False>'
+        assert repr(device) == '<gpiozero.InputDevice object on pin GPIO2, pull_up=True, is_active=False>'
         pin.drive_low()
         assert device.is_active
-        assert repr(device) == '<gpiozero.InputDevice object on pin MOCK2, pull_up=True, is_active=True>'
+        assert repr(device) == '<gpiozero.InputDevice object on pin GPIO2, pull_up=True, is_active=True>'
 
 def test_input_is_active_high():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with InputDevice(pin, pull_up=False) as device:
         pin.drive_high()
         assert device.is_active
-        assert repr(device) == '<gpiozero.InputDevice object on pin MOCK2, pull_up=False, is_active=True>'
+        assert repr(device) == '<gpiozero.InputDevice object on pin GPIO2, pull_up=False, is_active=True>'
         pin.drive_low()
         assert not device.is_active
-        assert repr(device) == '<gpiozero.InputDevice object on pin MOCK2, pull_up=False, is_active=False>'
+        assert repr(device) == '<gpiozero.InputDevice object on pin GPIO2, pull_up=False, is_active=False>'
 
 def test_input_pulled_up():
-    pin = MockPulledUpPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPulledUpPin)
     with pytest.raises(PinFixedPull):
         InputDevice(pin, pull_up=False)
 
 def test_input_event_activated():
     event = Event()
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with DigitalInputDevice(pin) as device:
         device.when_activated = lambda: event.set()
         assert not event.is_set()
@@ -71,7 +66,7 @@ def test_input_event_activated():
 
 def test_input_event_deactivated():
     event = Event()
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with DigitalInputDevice(pin) as device:
         device.when_deactivated = lambda: event.set()
         assert not event.is_set()
@@ -82,7 +77,7 @@ def test_input_event_deactivated():
 
 def test_input_partial_callback():
     event = Event()
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     def foo(a, b):
         event.set()
         return a + b
@@ -95,22 +90,22 @@ def test_input_partial_callback():
         assert event.is_set()
 
 def test_input_wait_active():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with DigitalInputDevice(pin) as device:
         pin.drive_high()
         assert device.wait_for_active(1)
         assert not device.wait_for_inactive(0)
 
 def test_input_wait_inactive():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with DigitalInputDevice(pin) as device:
         assert device.wait_for_inactive(1)
         assert not device.wait_for_active(0)
 
 def test_input_smoothed_attrib():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with SmoothedInputDevice(pin, threshold=0.5, queue_len=5, partial=False) as device:
-        assert repr(device) == '<gpiozero.SmoothedInputDevice object on pin=MOCK2, pull_up=False>'
+        assert repr(device) == '<gpiozero.SmoothedInputDevice object on pin GPIO2, pull_up=False>'
         assert device.threshold == 0.5
         assert device.queue_len == 5
         assert not device.partial
@@ -120,7 +115,7 @@ def test_input_smoothed_attrib():
             device.threshold = 1
 
 def test_input_smoothed_values():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with SmoothedInputDevice(pin) as device:
         device._queue.start()
         assert not device.is_active
@@ -130,7 +125,7 @@ def test_input_smoothed_values():
         assert device.wait_for_inactive(1)
 
 def test_input_button():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with Button(pin) as button:
         assert pin.pull == 'up'
         assert not button.is_pressed
@@ -142,7 +137,7 @@ def test_input_button():
         assert button.wait_for_release(1)
 
 def test_input_line_sensor():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with LineSensor(pin) as sensor:
         pin.drive_low() # logic is inverted for line sensor
         assert sensor.wait_for_line(1)
@@ -152,7 +147,7 @@ def test_input_line_sensor():
         assert not sensor.line_detected
 
 def test_input_motion_sensor():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with MotionSensor(pin) as sensor:
         pin.drive_high()
         assert sensor.wait_for_motion(1)
@@ -164,7 +159,7 @@ def test_input_motion_sensor():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_input_light_sensor():
-    pin = MockChargingPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockChargingPin)
     with LightSensor(pin) as sensor:
         pin.charge_time = 0.1
         assert sensor.wait_for_dark(1)
@@ -174,8 +169,8 @@ def test_input_light_sensor():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_input_distance_sensor():
-    echo_pin = MockPin(2)
+    echo_pin = Device._pin_factory.pin(2)
-    trig_pin = MockTriggerPin(3)
+    trig_pin = Device._pin_factory.pin(3, pin_class=MockTriggerPin)
     trig_pin.echo_pin = echo_pin
     trig_pin.echo_time = 0.02
     with pytest.raises(ValueError):

tests/test_mock_pin.py

@@ -11,25 +11,24 @@ from threading import Event
 
 import pytest
 
-from gpiozero.pins.mock import MockPin, MockPWMPin
+from gpiozero.pins.mock import MockPWMPin, MockPin
 from gpiozero import *
 
 
 def teardown_function(function):
-    MockPin.clear_pins()
+    Device._pin_factory.reset()
+
 
 # Some rough tests to make sure our MockPin is up to snuff. This is just
 # enough to get reasonable coverage but it's by no means comprehensive...
 
 def test_mock_pin_init():
-    with pytest.raises(TypeError):
-        MockPin()
     with pytest.raises(ValueError):
-        MockPin(60)
+        Device._pin_factory.pin(60)
-    assert MockPin(2).number == 2
+    assert Device._pin_factory.pin(2).number == 2
 
 def test_mock_pin_defaults():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     assert pin.bounce == None
     assert pin.edges == 'both'
     assert pin.frequency == None
@@ -39,30 +38,23 @@ def test_mock_pin_defaults():
     assert pin.when_changed == None
 
 def test_mock_pin_open_close():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     pin.close()
 
 def test_mock_pin_init_twice_same_pin():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(pin1.number)
+    pin2 = Device._pin_factory.pin(pin1.number)
     assert pin1 is pin2
 
 def test_mock_pin_init_twice_different_pin():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2)
-    pin2 = MockPin(pin1.number+1)
+    pin2 = Device._pin_factory.pin(pin1.number+1)
     assert pin1 != pin2
     assert pin1.number == 2
     assert pin2.number == pin1.number+1
 
-def test_mock_pwm_pin_init():
-    with pytest.raises(TypeError):
-        MockPWMPin()
-    with pytest.raises(ValueError):
-        MockPWMPin(60)
-    assert MockPWMPin(2).number == 2
-
 def test_mock_pwm_pin_defaults():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     assert pin.bounce == None
     assert pin.edges == 'both'
     assert pin.frequency == None
@@ -72,38 +64,38 @@ def test_mock_pwm_pin_defaults():
     assert pin.when_changed == None
 
 def test_mock_pwm_pin_open_close():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     pin.close()
 
 def test_mock_pwm_pin_init_twice_same_pin():
-    pin1 = MockPWMPin(2)
+    pin1 = Device._pin_factory.pin(2, pin_class=MockPWMPin)
-    pin2 = MockPWMPin(pin1.number)
+    pin2 = Device._pin_factory.pin(pin1.number, pin_class=MockPWMPin)
     assert pin1 is pin2
 
 def test_mock_pwm_pin_init_twice_different_pin():
-    pin1 = MockPWMPin(2)
+    pin1 = Device._pin_factory.pin(2, pin_class=MockPWMPin)
-    pin2 = MockPWMPin(pin1.number+1)
+    pin2 = Device._pin_factory.pin(pin1.number + 1, pin_class=MockPWMPin)
     assert pin1 != pin2
     assert pin1.number == 2
     assert pin2.number == pin1.number+1
 
 def test_mock_pin_init_twice_different_modes():
-    pin1 = MockPin(2)
+    pin1 = Device._pin_factory.pin(2, pin_class=MockPin)
-    pin2 = MockPWMPin(pin1.number+1)
+    pin2 = Device._pin_factory.pin(pin1.number + 1, pin_class=MockPWMPin)
     assert pin1 != pin2
     with pytest.raises(ValueError):
-        pin3 = MockPWMPin(pin1.number)
+        Device._pin_factory.pin(pin1.number, pin_class=MockPWMPin)
     with pytest.raises(ValueError):
-        pin4 = MockPin(pin2.number)
+        Device._pin_factory.pin(pin2.number, pin_class=MockPin)
 
 def test_mock_pin_frequency_unsupported():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     pin.frequency = None
     with pytest.raises(PinPWMUnsupported):
         pin.frequency = 100
 
 def test_mock_pin_frequency_supported():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     pin.function = 'output'
     assert pin.frequency is None
     pin.frequency = 100
@@ -112,7 +104,7 @@ def test_mock_pin_frequency_supported():
     assert not pin.state
 
 def test_mock_pin_pull():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     pin.function = 'input'
     assert pin.pull == 'floating'
     pin.pull = 'up'
@@ -121,7 +113,7 @@ def test_mock_pin_pull():
     assert not pin.state
 
 def test_mock_pin_state():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with pytest.raises(PinSetInput):
         pin.state = 1
     pin.function = 'output'
@@ -134,7 +126,7 @@ def test_mock_pin_state():
     assert pin.state == 1
 
 def test_mock_pwm_pin_state():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with pytest.raises(PinSetInput):
         pin.state = 1
     pin.function = 'output'
@@ -147,7 +139,7 @@ def test_mock_pwm_pin_state():
     assert pin.state == 0.5
 
 def test_mock_pin_edges():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     assert pin.when_changed is None
     fired = Event()
     pin.function = 'input'

tests/test_outputs.py

@@ -16,15 +16,16 @@ except ImportError:
 
 import pytest
 
-from gpiozero.pins.mock import MockPin, MockPWMPin
+from gpiozero.pins.mock import MockPWMPin
 from gpiozero import *
 
 
 def teardown_function(function):
-    MockPin.clear_pins()
+    Device._pin_factory.reset()
+
 
 def test_output_initial_values():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with OutputDevice(pin, initial_value=False) as device:
         assert pin.function == 'output'
         assert not pin.state
@@ -35,7 +36,7 @@ def test_output_initial_values():
         assert state == pin.state
 
 def test_output_write_active_high():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with OutputDevice(pin) as device:
         device.on()
         assert pin.state
@@ -43,7 +44,7 @@ def test_output_write_active_high():
         assert not pin.state
 
 def test_output_write_active_low():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with OutputDevice(pin, active_high=False) as device:
         device.on()
         assert not pin.state
@@ -51,7 +52,7 @@ def test_output_write_active_low():
         assert pin.state
 
 def test_output_write_closed():
-    with OutputDevice(MockPin(2)) as device:
+    with OutputDevice(Device._pin_factory.pin(2)) as device:
         device.close()
         assert device.closed
         device.close()
@@ -60,14 +61,14 @@ def test_output_write_closed():
             device.on()
 
 def test_output_write_silly():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with OutputDevice(pin) as device:
         pin.function = 'input'
         with pytest.raises(AttributeError):
             device.on()
 
 def test_output_value():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with OutputDevice(pin) as device:
         assert not device.value
         assert not pin.state
@@ -79,7 +80,7 @@ def test_output_value():
         assert not pin.state
 
 def test_output_digital_toggle():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with DigitalOutputDevice(pin) as device:
         assert not device.value
         assert not pin.state
@@ -93,7 +94,7 @@ def test_output_digital_toggle():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_output_blink_background():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with DigitalOutputDevice(pin) as device:
         start = time()
         device.blink(0.1, 0.1, n=2)
@@ -111,7 +112,7 @@ def test_output_blink_background():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_output_blink_foreground():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with DigitalOutputDevice(pin) as device:
         start = time()
         device.blink(0.1, 0.1, n=2, background=False)
@@ -125,7 +126,7 @@ def test_output_blink_foreground():
             ])
 
 def test_output_blink_interrupt_on():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with DigitalOutputDevice(pin) as device:
         device.blink(1, 0.1)
         sleep(0.2)
@@ -133,7 +134,7 @@ def test_output_blink_interrupt_on():
         pin.assert_states([False, True, False])
 
 def test_output_blink_interrupt_off():
-    pin = MockPin(2)
+    pin = Device._pin_factory.pin(2)
     with DigitalOutputDevice(pin) as device:
         device.blink(0.1, 1)
         sleep(0.2)
@@ -142,14 +143,14 @@ def test_output_blink_interrupt_off():
 
 def test_output_pwm_bad_initial_value():
     with pytest.raises(ValueError):
-        PWMOutputDevice(MockPin(2), initial_value=2)
+        PWMOutputDevice(Device._pin_factory.pin(2), initial_value=2)
 
 def test_output_pwm_not_supported():
     with pytest.raises(AttributeError):
-        PWMOutputDevice(MockPin(2))
+        PWMOutputDevice(Device._pin_factory.pin(2))
 
 def test_output_pwm_states():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with PWMOutputDevice(pin) as device:
         device.value = 0.1
         device.value = 0.2
@@ -157,7 +158,7 @@ def test_output_pwm_states():
         pin.assert_states([0.0, 0.1, 0.2, 0.0])
 
 def test_output_pwm_read():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with PWMOutputDevice(pin, frequency=100) as device:
         assert device.frequency == 100
         device.value = 0.1
@@ -170,14 +171,14 @@ def test_output_pwm_read():
         assert device.frequency is None
 
 def test_output_pwm_write():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with PWMOutputDevice(pin) as device:
         device.on()
         device.off()
         pin.assert_states([False, True, False])
 
 def test_output_pwm_toggle():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with PWMOutputDevice(pin) as device:
         device.toggle()
         device.value = 0.5
@@ -187,7 +188,7 @@ def test_output_pwm_toggle():
         pin.assert_states([False, True, 0.5, 0.1, 0.9, False])
 
 def test_output_pwm_active_high_read():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with PWMOutputDevice(pin, active_high=False) as device:
         device.value = 0.1
         assert isclose(device.value, 0.1)
@@ -196,17 +197,18 @@ def test_output_pwm_active_high_read():
         assert device.value
 
 def test_output_pwm_bad_value():
-    with pytest.raises(ValueError):
+    with PWMOutputDevice(Device._pin_factory.pin(2, pin_class=MockPWMPin)) as device:
-        PWMOutputDevice(MockPWMPin(2)).value = 2
+        with pytest.raises(ValueError):
+            device.value = 2
 
 def test_output_pwm_write_closed():
-    device = PWMOutputDevice(MockPWMPin(2))
+    with PWMOutputDevice(Device._pin_factory.pin(2, pin_class=MockPWMPin)) as device:
-    device.close()
+        device.close()
-    with pytest.raises(GPIODeviceClosed):
+        with pytest.raises(GPIODeviceClosed):
-        device.on()
+            device.on()
 
 def test_output_pwm_write_silly():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with PWMOutputDevice(pin) as device:
         pin.function = 'input'
         with pytest.raises(AttributeError):
@@ -215,7 +217,7 @@ def test_output_pwm_write_silly():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_output_pwm_blink_background():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with PWMOutputDevice(pin) as device:
         start = time()
         device.blink(0.1, 0.1, n=2)
@@ -233,7 +235,7 @@ def test_output_pwm_blink_background():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_output_pwm_blink_foreground():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with PWMOutputDevice(pin) as device:
         start = time()
         device.blink(0.1, 0.1, n=2, background=False)
@@ -249,7 +251,7 @@ def test_output_pwm_blink_foreground():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_output_pwm_fade_background():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with PWMOutputDevice(pin) as device:
         start = time()
         device.blink(0, 0, 0.2, 0.2, n=2)
@@ -283,7 +285,7 @@ def test_output_pwm_fade_background():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_output_pwm_fade_foreground():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with PWMOutputDevice(pin) as device:
         start = time()
         device.blink(0, 0, 0.2, 0.2, n=2, background=False)
@@ -315,7 +317,7 @@ def test_output_pwm_fade_foreground():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_output_pwm_pulse_background():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with PWMOutputDevice(pin) as device:
         start = time()
         device.pulse(0.2, 0.2, n=2)
@@ -349,7 +351,7 @@ def test_output_pwm_pulse_background():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_output_pwm_pulse_foreground():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with PWMOutputDevice(pin) as device:
         start = time()
         device.pulse(0.2, 0.2, n=2, background=False)
@@ -379,7 +381,7 @@ def test_output_pwm_pulse_foreground():
             ])
 
 def test_output_pwm_blink_interrupt():
-    pin = MockPWMPin(2)
+    pin = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with PWMOutputDevice(pin) as device:
         device.blink(1, 0.1)
         sleep(0.2)
@@ -391,7 +393,7 @@ def test_rgbled_missing_pins():
         RGBLED()
 
 def test_rgbled_initial_value():
-    r, g, b = (MockPWMPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i, pin_class=MockPWMPin) for i in (1, 2, 3))
     with RGBLED(r, g, b, initial_value=(0.1, 0.2, 0)) as device:
         assert r.frequency
         assert g.frequency
@@ -401,24 +403,24 @@ def test_rgbled_initial_value():
         assert isclose(b.state, 0.0)
 
 def test_rgbled_initial_value_nonpwm():
-    r, g, b = (MockPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
     with RGBLED(r, g, b, pwm=False, initial_value=(0, 1, 1)) as device:
         assert r.state == 0
         assert g.state == 1
         assert b.state == 1
 
 def test_rgbled_initial_bad_value():
-    r, g, b = (MockPWMPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i, pin_class=MockPWMPin) for i in (1, 2, 3))
     with pytest.raises(ValueError):
         RGBLED(r, g, b, initial_value=(0.1, 0.2, 1.2))
 
 def test_rgbled_initial_bad_value_nonpwm():
-    r, g, b = (MockPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
     with pytest.raises(ValueError):
         RGBLED(r, g, b, pwm=False, initial_value=(0.1, 0.2, 0))
 
 def test_rgbled_value():
-    r, g, b = (MockPWMPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i, pin_class=MockPWMPin) for i in (1, 2, 3))
     with RGBLED(r, g, b) as device:
         assert isinstance(device._leds[0], PWMLED)
         assert isinstance(device._leds[1], PWMLED)
@@ -436,7 +438,7 @@ def test_rgbled_value():
         assert device.value == (0.5, 0.5, 0.5)
 
 def test_rgbled_value_nonpwm():
-    r, g, b = (MockPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
     with RGBLED(r, g, b, pwm=False) as device:
         assert isinstance(device._leds[0], LED)
         assert isinstance(device._leds[1], LED)
@@ -451,7 +453,7 @@ def test_rgbled_value_nonpwm():
         assert device.value == (0, 0, 0)
 
 def test_rgbled_bad_value():
-    r, g, b = (MockPWMPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i, pin_class=MockPWMPin) for i in (1, 2, 3))
     with RGBLED(r, g, b) as device:
         with pytest.raises(ValueError):
             device.value = (2, 0, 0)
@@ -460,7 +462,7 @@ def test_rgbled_bad_value():
             device.value = (0, -1, 0)
 
 def test_rgbled_bad_value_nonpwm():
-    r, g, b = (MockPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
     with RGBLED(r, g, b, pwm=False) as device:
         with pytest.raises(ValueError):
             device.value = (2, 0, 0)
@@ -478,7 +480,7 @@ def test_rgbled_bad_value_nonpwm():
             device.value = (0, 0, 0.5)
 
 def test_rgbled_toggle():
-    r, g, b = (MockPWMPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i, pin_class=MockPWMPin) for i in (1, 2, 3))
     with RGBLED(r, g, b) as device:
         assert not device.is_active
         assert device.value == (0, 0, 0)
@@ -490,7 +492,7 @@ def test_rgbled_toggle():
         assert device.value == (0, 0, 0)
 
 def test_rgbled_toggle_nonpwm():
-    r, g, b = (MockPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
     with RGBLED(r, g, b, pwm=False) as device:
         assert not device.is_active
         assert device.value == (0, 0, 0)
@@ -501,10 +503,18 @@ def test_rgbled_toggle_nonpwm():
         assert not device.is_active
         assert device.value == (0, 0, 0)
 
+def test_rgbled_blink_nonpwm():
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
+    with RGBLED(r, g, b, pwm=False) as device:
+        with pytest.raises(ValueError):
+            device.blink(fade_in_time=1)
+        with pytest.raises(ValueError):
+            device.blink(fade_out_time=1)
+
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_rgbled_blink_background():
-    r, g, b = (MockPWMPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i, pin_class=MockPWMPin) for i in (1, 2, 3))
     with RGBLED(r, g, b) as device:
         start = time()
         device.blink(0.1, 0.1, n=2)
@@ -525,7 +535,7 @@ def test_rgbled_blink_background():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_rgbled_blink_background_nonpwm():
-    r, g, b = (MockPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
     with RGBLED(r, g, b, pwm=False) as device:
         start = time()
         device.blink(0.1, 0.1, n=2)
@@ -546,7 +556,7 @@ def test_rgbled_blink_background_nonpwm():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_rgbled_blink_foreground():
-    r, g, b = (MockPWMPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i, pin_class=MockPWMPin) for i in (1, 2, 3))
     with RGBLED(r, g, b) as device:
         start = time()
         device.blink(0.1, 0.1, n=2, background=False)
@@ -565,7 +575,7 @@ def test_rgbled_blink_foreground():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_rgbled_blink_foreground_nonpwm():
-    r, g, b = (MockPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
     with RGBLED(r, g, b, pwm=False) as device:
         start = time()
         device.blink(0.1, 0.1, n=2, background=False)
@@ -584,7 +594,7 @@ def test_rgbled_blink_foreground_nonpwm():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_rgbled_fade_background():
-    r, g, b = (MockPWMPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i, pin_class=MockPWMPin) for i in (1, 2, 3))
     with RGBLED(r, g, b) as device:
         start = time()
         device.blink(0, 0, 0.2, 0.2, n=2)
@@ -619,7 +629,7 @@ def test_rgbled_fade_background():
         b.assert_states_and_times(expected)
 
 def test_rgbled_fade_background_nonpwm():
-    r, g, b = (MockPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
     with RGBLED(r, g, b, pwm=False) as device:
         with pytest.raises(ValueError):
             device.blink(0, 0, 0.2, 0.2, n=2)
@@ -627,7 +637,7 @@ def test_rgbled_fade_background_nonpwm():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_rgbled_fade_foreground():
-    r, g, b = (MockPWMPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i, pin_class=MockPWMPin) for i in (1, 2, 3))
     with RGBLED(r, g, b) as device:
         start = time()
         device.blink(0, 0, 0.2, 0.2, n=2, background=False)
@@ -660,7 +670,7 @@ def test_rgbled_fade_foreground():
         b.assert_states_and_times(expected)
 
 def test_rgbled_fade_foreground_nonpwm():
-    r, g, b = (MockPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
     with RGBLED(r, g, b, pwm=False) as device:
         with pytest.raises(ValueError):
             device.blink(0, 0, 0.2, 0.2, n=2, background=False)
@@ -668,7 +678,7 @@ def test_rgbled_fade_foreground_nonpwm():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_rgbled_pulse_background():
-    r, g, b = (MockPWMPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i, pin_class=MockPWMPin) for i in (1, 2, 3))
     with RGBLED(r, g, b) as device:
         start = time()
         device.pulse(0.2, 0.2, n=2)
@@ -703,7 +713,7 @@ def test_rgbled_pulse_background():
         b.assert_states_and_times(expected)
 
 def test_rgbled_pulse_background_nonpwm():
-    r, g, b = (MockPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
     with RGBLED(r, g, b, pwm=False) as device:
         with pytest.raises(ValueError):
             device.pulse(0.2, 0.2, n=2)
@@ -711,7 +721,7 @@ def test_rgbled_pulse_background_nonpwm():
 @pytest.mark.skipif(hasattr(sys, 'pypy_version_info'),
                     reason='timing is too random on pypy')
 def test_rgbled_pulse_foreground():
-    r, g, b = (MockPWMPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i, pin_class=MockPWMPin) for i in (1, 2, 3))
     with RGBLED(r, g, b) as device:
         start = time()
         device.pulse(0.2, 0.2, n=2, background=False)
@@ -744,13 +754,13 @@ def test_rgbled_pulse_foreground():
         b.assert_states_and_times(expected)
 
 def test_rgbled_pulse_foreground_nonpwm():
-    r, g, b = (MockPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
     with RGBLED(r, g, b, pwm=False) as device:
         with pytest.raises(ValueError):
             device.pulse(0.2, 0.2, n=2, background=False)
 
 def test_rgbled_blink_interrupt():
-    r, g, b = (MockPWMPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i, pin_class=MockPWMPin) for i in (1, 2, 3))
     with RGBLED(r, g, b) as device:
         device.blink(1, 0.1)
         sleep(0.2)
@@ -760,7 +770,7 @@ def test_rgbled_blink_interrupt():
         b.assert_states([0, 1, 0])
 
 def test_rgbled_blink_interrupt_nonpwm():
-    r, g, b = (MockPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
     with RGBLED(r, g, b, pwm=False) as device:
         device.blink(1, 0.1)
         sleep(0.2)
@@ -770,7 +780,7 @@ def test_rgbled_blink_interrupt_nonpwm():
         b.assert_states([0, 1, 0])
 
 def test_rgbled_close():
-    r, g, b = (MockPWMPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i, pin_class=MockPWMPin) for i in (1, 2, 3))
     with RGBLED(r, g, b) as device:
         assert not device.closed
         device.close()
@@ -779,7 +789,7 @@ def test_rgbled_close():
         assert device.closed
 
 def test_rgbled_close_nonpwm():
-    r, g, b = (MockPin(i) for i in (1, 2, 3))
+    r, g, b = (Device._pin_factory.pin(i) for i in (1, 2, 3))
     with RGBLED(r, g, b, pwm=False) as device:
         assert not device.closed
         device.close()
@@ -792,8 +802,8 @@ def test_motor_missing_pins():
         Motor()
 
 def test_motor_pins():
-    f = MockPWMPin(1)
+    f = Device._pin_factory.pin(1, pin_class=MockPWMPin)
-    b = MockPWMPin(2)
+    b = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with Motor(f, b) as device:
         assert device.forward_device.pin is f
         assert isinstance(device.forward_device, PWMOutputDevice)
@@ -801,8 +811,8 @@ def test_motor_pins():
         assert isinstance(device.backward_device, PWMOutputDevice)
 
 def test_motor_pins_nonpwm():
-    f = MockPin(1)
+    f = Device._pin_factory.pin(1)
-    b = MockPin(2)
+    b = Device._pin_factory.pin(2)
     with Motor(f, b, pwm=False) as device:
         assert device.forward_device.pin is f
         assert isinstance(device.forward_device, DigitalOutputDevice)
@@ -810,8 +820,8 @@ def test_motor_pins_nonpwm():
         assert isinstance(device.backward_device, DigitalOutputDevice)
 
 def test_motor_close():
-    f = MockPWMPin(1)
+    f = Device._pin_factory.pin(1, pin_class=MockPWMPin)
-    b = MockPWMPin(2)
+    b = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with Motor(f, b) as device:
         device.close()
         assert device.closed
@@ -821,8 +831,8 @@ def test_motor_close():
         assert device.closed
 
 def test_motor_close_nonpwm():
-    f = MockPin(1)
+    f = Device._pin_factory.pin(1)
-    b = MockPin(2)
+    b = Device._pin_factory.pin(2)
     with Motor(f, b, pwm=False) as device:
         device.close()
         assert device.closed
@@ -830,8 +840,8 @@ def test_motor_close_nonpwm():
         assert device.backward_device.pin is None
 
 def test_motor_value():
-    f = MockPWMPin(1)
+    f = Device._pin_factory.pin(1, pin_class=MockPWMPin)
-    b = MockPWMPin(2)
+    b = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with Motor(f, b) as device:
         device.value = -1
         assert device.is_active
@@ -855,8 +865,8 @@ def test_motor_value():
         assert b.state == 0 and f.state == 0
 
 def test_motor_value_nonpwm():
-    f = MockPin(1)
+    f = Device._pin_factory.pin(1)
-    b = MockPin(2)
+    b = Device._pin_factory.pin(2)
     with Motor(f, b, pwm=False) as device:
         device.value = -1
         assert device.is_active
@@ -872,17 +882,21 @@ def test_motor_value_nonpwm():
         assert b.state == 0 and f.state == 0
 
 def test_motor_bad_value():
-    f = MockPWMPin(1)
+    f = Device._pin_factory.pin(1, pin_class=MockPWMPin)
-    b = MockPWMPin(2)
+    b = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with Motor(f, b) as device:
         with pytest.raises(ValueError):
             device.value = -2
         with pytest.raises(ValueError):
             device.value = 2
+        with pytest.raises(ValueError):
+            device.forward(2)
+        with pytest.raises(ValueError):
+            device.backward(2)
 
 def test_motor_bad_value_nonpwm():
-    f = MockPin(1)
+    f = Device._pin_factory.pin(1)
-    b = MockPin(2)
+    b = Device._pin_factory.pin(2)
     with Motor(f, b, pwm=False) as device:
         with pytest.raises(ValueError):
             device.value = -2
@@ -894,8 +908,8 @@ def test_motor_bad_value_nonpwm():
             device.value = -0.5
 
 def test_motor_reverse():
-    f = MockPWMPin(1)
+    f = Device._pin_factory.pin(1, pin_class=MockPWMPin)
-    b = MockPWMPin(2)
+    b = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with Motor(f, b) as device:
         device.forward()
         assert device.value == 1
@@ -911,8 +925,8 @@ def test_motor_reverse():
         assert b.state == 0 and f.state == 0.5
 
 def test_motor_reverse_nonpwm():
-    f = MockPin(1)
+    f = Device._pin_factory.pin(1)
-    b = MockPin(2)
+    b = Device._pin_factory.pin(2)
     with Motor(f, b, pwm=False) as device:
         device.forward()
         assert device.value == 1
@@ -922,13 +936,13 @@ def test_motor_reverse_nonpwm():
         assert b.state == 1 and f.state == 0
 
 def test_servo_pins():
-    p = MockPWMPin(1)
+    p = Device._pin_factory.pin(1, pin_class=MockPWMPin)
     with Servo(p) as device:
         assert device.pwm_device.pin is p
         assert isinstance(device.pwm_device, PWMOutputDevice)
 
 def test_servo_bad_value():
-    p = MockPWMPin(1)
+    p = Device._pin_factory.pin(1, pin_class=MockPWMPin)
     with pytest.raises(ValueError):
         Servo(p, initial_value=2)
     with pytest.raises(ValueError):
@@ -937,12 +951,12 @@ def test_servo_bad_value():
         Servo(p, max_pulse_width=30/1000)
 
 def test_servo_pins_nonpwm():
-    p = MockPin(2)
+    p = Device._pin_factory.pin(2)
     with pytest.raises(PinPWMUnsupported):
         Servo(p)
 
 def test_servo_close():
-    p = MockPWMPin(2)
+    p = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with Servo(p) as device:
         device.close()
         assert device.closed
@@ -951,7 +965,7 @@ def test_servo_close():
         assert device.closed
 
 def test_servo_pulse_width():
-    p = MockPWMPin(2)
+    p = Device._pin_factory.pin(2, pin_class=MockPWMPin)
     with Servo(p, min_pulse_width=5/10000, max_pulse_width=25/10000) as device:
         assert isclose(device.min_pulse_width, 5/10000)
         assert isclose(device.max_pulse_width, 25/10000)
@@ -965,7 +979,7 @@ def test_servo_pulse_width():
         assert device.pulse_width is None
 
 def test_servo_values():
-    p = MockPWMPin(1)
+    p = Device._pin_factory.pin(1, pin_class=MockPWMPin)
     with Servo(p) as device:
         device.min()
         assert device.is_active
@@ -992,13 +1006,13 @@ def test_servo_values():
         assert device.value is None
 
 def test_angular_servo_range():
-    p = MockPWMPin(1)
+    p = Device._pin_factory.pin(1, pin_class=MockPWMPin)
     with AngularServo(p, initial_angle=15, min_angle=0, max_angle=90) as device:
         assert device.min_angle == 0
         assert device.max_angle == 90
 
 def test_angular_servo_angles():
-    p = MockPWMPin(1)
+    p = Device._pin_factory.pin(1, pin_class=MockPWMPin)
     with AngularServo(p) as device:
         device.angle = 0
         assert device.angle == 0

tests/test_pins_data.py

@@ -11,44 +11,44 @@ import re
 import pytest
 from mock import patch, MagicMock
 
-import gpiozero.devices
 import gpiozero.pins.data
-import gpiozero.pins.native
+import gpiozero.pins.local
-from gpiozero.pins.data import pi_info, Style, HeaderInfo, PinInfo
+from gpiozero.pins.local import LocalPiFactory
-from gpiozero import PinMultiplePins, PinNoPins, PinUnknownPi
+from gpiozero.pins.data import Style, HeaderInfo, PinInfo
+from gpiozero import *
 
 
 def test_pi_revision():
-    save_factory = gpiozero.devices.pin_factory
+    # We're not using _set_pin_factory here because we don't want to implicitly
-    try:
+    # close the old instance, just replace it while we test stuff
+    with patch('gpiozero.devices.Device._pin_factory', LocalPiFactory()):
         # Can't use MockPin for this as we want something that'll actually try
         # and read /proc/cpuinfo (MockPin simply parrots the 2B's data);
-        # NativePin is used as we're guaranteed to be able to import it
+        # LocalPiFactory is used as we can definitely instantiate it (strictly
-        gpiozero.devices.pin_factory = gpiozero.pins.native.NativePin
+        # speaking it's abstract but we're only interested in the pi_info
+        # stuff)
         with patch('io.open') as m:
             m.return_value.__enter__.return_value = ['lots of irrelevant', 'lines', 'followed by', 'Revision: 0002', 'Serial:  xxxxxxxxxxx']
             assert pi_info().revision == '0002'
-            # LocalPin caches the revision (because realistically it isn't going to
+            # LocalPiFactory caches the revision (because realistically it
-            # change at runtime); we need to wipe it here though
+            # isn't going to change at runtime); we need to wipe it here though
-            gpiozero.pins.native.NativePin._PI_REVISION = None
+            Device._pin_factory._info = None
             m.return_value.__enter__.return_value = ['Revision: a21042']
             assert pi_info().revision == 'a21042'
             # Check over-volting result (some argument over whether this is 7 or
             # 8 character result; make sure both work)
-            gpiozero.pins.native.NativePin._PI_REVISION = None
+            Device._pin_factory._info = None
             m.return_value.__enter__.return_value = ['Revision: 1000003']
             assert pi_info().revision == '0003'
-            gpiozero.pins.native.NativePin._PI_REVISION = None
+            Device._pin_factory._info = None
             m.return_value.__enter__.return_value = ['Revision: 100003']
             assert pi_info().revision == '0003'
             with pytest.raises(PinUnknownPi):
                 m.return_value.__enter__.return_value = ['nothing', 'relevant', 'at all']
-                gpiozero.pins.native.NativePin._PI_REVISION = None
+                Device._pin_factory._info = None
                 pi_info()
             with pytest.raises(PinUnknownPi):
                 pi_info('0fff')
-    finally:
-        gpiozero.devices.pin_factory = save_factory
 
 def test_pi_info():
     r = pi_info('900011')
@@ -73,14 +73,14 @@ def test_pi_info_other_types():
 
 def test_physical_pins():
     # Assert physical pins for some well-known Pi's; a21041 is a Pi2B
-    assert pi_info('a21041').physical_pins('3V3') == {('P1', 1), ('P1', 17)}
+    assert pi_info('a21041').physical_pins('3V3') == {('J8', 1), ('J8', 17)}
-    assert pi_info('a21041').physical_pins('GPIO2') == {('P1', 3)}
+    assert pi_info('a21041').physical_pins('GPIO2') == {('J8', 3)}
     assert pi_info('a21041').physical_pins('GPIO47') == set()
 
 def test_physical_pin():
     with pytest.raises(PinMultiplePins):
         assert pi_info('a21041').physical_pin('GND')
-    assert pi_info('a21041').physical_pin('GPIO3') == ('P1', 5)
+    assert pi_info('a21041').physical_pin('GPIO3') == ('J8', 5)
     with pytest.raises(PinNoPins):
         assert pi_info('a21041').physical_pin('GPIO47')
 
@@ -114,6 +114,18 @@ def test_pprint_content():
         pi_info('0014').headers['SODIMM'].pprint(color=False)
         assert len(''.join(stdout.output).splitlines()) == 100
 
+def test_format_content():
+    with patch('sys.stdout') as stdout:
+        stdout.output = []
+        stdout.write = lambda buf: stdout.output.append(buf)
+        pi_info('900092').pprint(color=False)
+        s = ''.join(stdout.output)
+        assert '{0:mono}\n'.format(pi_info('900092')) == s
+        stdout.output = []
+        pi_info('900092').pprint(color=True)
+        s = ''.join(stdout.output)
+        assert '{0:color full}\n'.format(pi_info('900092')) == s
+
 def test_pprint_headers():
     assert len(pi_info('0002').headers) == 1
     assert len(pi_info('000e').headers) == 2
@@ -133,7 +145,8 @@ def test_pprint_headers():
         stdout.output = []
         pi_info('900092').pprint()
         s = ''.join(stdout.output)
-        assert 'P1:\n' in s
+        assert 'J8:\n' in s
+        assert 'P1:\n' not in s
         assert 'P5:\n' not in s
 
 def test_pprint_color():
@@ -194,11 +207,12 @@ def test_pprint_missing_pin():
                 assert ('(%d)' % i)
 
 def test_pprint_rows_cols():
-    assert '{0:row1}'.format(pi_info('900092').headers['P1']) == '1o'
+    assert '{0:row1}'.format(pi_info('900092').headers['J8']) == '1o'
-    assert '{0:row2}'.format(pi_info('900092').headers['P1']) == 'oo'
+    assert '{0:row2}'.format(pi_info('900092').headers['J8']) == 'oo'
     assert '{0:col1}'.format(pi_info('0002').headers['P1']) == '1oooooooooooo'
     assert '{0:col2}'.format(pi_info('0002').headers['P1']) == 'ooooooooooooo'
     with pytest.raises(ValueError):
         '{0:row16}'.format(pi_info('0002').headers['P1'])
     with pytest.raises(ValueError):
         '{0:col3}'.format(pi_info('0002').headers['P1'])
+

tests/test_spi.py

@@ -4,93 +4,113 @@ from __future__ import (
     print_function,
     division,
     )
+nstr = str
 str = type('')
 
 
 import sys
-import mock
 import pytest
+from array import array
+from mock import patch
 from collections import namedtuple
 
+from gpiozero.pins.native import NativeFactory
+from gpiozero.pins.local import (
+    LocalPiHardwareSPI,
+    LocalPiSoftwareSPI,
+    LocalPiHardwareSPIShared,
+    LocalPiSoftwareSPIShared,
+    )
+from gpiozero.pins.mock import MockSPIDevice
 from gpiozero import *
-from gpiozero.pins.mock import MockPin, MockSPIDevice
-from gpiozero.spi import *
 
 
-def setup_function(function):
-    import gpiozero.devices
-    gpiozero.devices.pin_factory = MockPin
-
 def teardown_function(function):
-    MockPin.clear_pins()
+    Device._pin_factory.reset()
 
 
 def test_spi_hardware_params():
-    with mock.patch('gpiozero.spi.SpiDev') as spidev:
+    with patch('os.open'), patch('mmap.mmap') as mmap_mmap, patch('io.open') as io_open:
-        with SPI() as device:
+        mmap_mmap.return_value = array(nstr('B'), (0,) * 4096)
-            assert isinstance(device, SPIHardwareInterface)
+        io_open.return_value.__enter__.return_value = ['Revision: a21042']
-        with SPI(port=0, device=0) as device:
+        with patch('gpiozero.devices.Device._pin_factory', NativeFactory()), \
-            assert isinstance(device, SPIHardwareInterface)
+                patch('gpiozero.pins.local.SpiDev'):
-        with SPI(port=0, device=1) as device:
+            with Device._pin_factory.spi() as device:
-            assert isinstance(device, SPIHardwareInterface)
+                assert isinstance(device, LocalPiHardwareSPI)
-        with SPI(clock_pin=11) as device:
+            with Device._pin_factory.spi(port=0, device=0) as device:
-            assert isinstance(device, SPIHardwareInterface)
+                assert isinstance(device, LocalPiHardwareSPI)
-        with SPI(clock_pin=11, mosi_pin=10, select_pin=8) as device:
+            with Device._pin_factory.spi(port=0, device=1) as device:
-            assert isinstance(device, SPIHardwareInterface)
+                assert isinstance(device, LocalPiHardwareSPI)
-        with SPI(clock_pin=11, mosi_pin=10, select_pin=7) as device:
+            with Device._pin_factory.spi(clock_pin=11) as device:
-            assert isinstance(device, SPIHardwareInterface)
+                assert isinstance(device, LocalPiHardwareSPI)
-        with SPI(shared=True) as device:
+            with Device._pin_factory.spi(clock_pin=11, mosi_pin=10, select_pin=8) as device:
-            assert isinstance(device, SharedSPIHardwareInterface)
+                assert isinstance(device, LocalPiHardwareSPI)
-        with pytest.raises(ValueError):
+            with Device._pin_factory.spi(clock_pin=11, mosi_pin=10, select_pin=7) as device:
-            SPI(port=1)
+                assert isinstance(device, LocalPiHardwareSPI)
-        with pytest.raises(ValueError):
+            with Device._pin_factory.spi(shared=True) as device:
-            SPI(device=2)
+                assert isinstance(device, LocalPiHardwareSPIShared)
-        with pytest.raises(ValueError):
+            with pytest.raises(ValueError):
-            SPI(port=0, clock_pin=12)
+                Device._pin_factory.spi(port=1)
-        with pytest.raises(ValueError):
+            with pytest.raises(ValueError):
-            SPI(foo='bar')
+                Device._pin_factory.spi(device=2)
+            with pytest.raises(ValueError):
+                Device._pin_factory.spi(port=0, clock_pin=12)
+            with pytest.raises(ValueError):
+                Device._pin_factory.spi(foo='bar')
 
 def test_spi_software_params():
-    with mock.patch('gpiozero.spi.SpiDev') as spidev:
+    with patch('os.open'), patch('mmap.mmap') as mmap_mmap, patch('io.open') as io_open:
-        with SPI(select_pin=6) as device:
+        mmap_mmap.return_value = array(nstr('B'), (0,) * 4096)
-            assert isinstance(device, SPISoftwareInterface)
+        io_open.return_value.__enter__.return_value = ['Revision: a21042']
-        with SPI(clock_pin=11, mosi_pin=9, miso_pin=10) as device:
+        with patch('gpiozero.devices.Device._pin_factory', NativeFactory()), \
-            assert isinstance(device, SPISoftwareInterface)
+                patch('gpiozero.pins.local.SpiDev'):
-        with SPI(select_pin=6, shared=True) as device:
+            with Device._pin_factory.spi(select_pin=6) as device:
-            assert isinstance(device, SharedSPISoftwareInterface)
+                assert isinstance(device, LocalPiSoftwareSPI)
-    # Ensure software fallback works when SpiDev isn't present
+            with Device._pin_factory.spi(clock_pin=11, mosi_pin=9, miso_pin=10) as device:
-    with SPI() as device:
+                assert isinstance(device, LocalPiSoftwareSPI)
-        assert isinstance(device, SPISoftwareInterface)
+            with Device._pin_factory.spi(select_pin=6, shared=True) as device:
+                assert isinstance(device, LocalPiSoftwareSPIShared)
+        with patch('gpiozero.devices.Device._pin_factory', NativeFactory()):
+            # Clear out the old factory's pins cache (this is only necessary
+            # because we're being very naughty switching out pin factories)
+            Device._pin_factory.pins.clear()
+            # Ensure software fallback works when SpiDev isn't present
+            with Device._pin_factory.spi() as device:
+                assert isinstance(device, LocalPiSoftwareSPI)
 
 def test_spi_hardware_conflict():
-    with mock.patch('gpiozero.spi.SpiDev') as spidev:
+    with patch('gpiozero.pins.local.SpiDev') as spidev:
         with LED(11) as led:
             with pytest.raises(GPIOPinInUse):
-                SPI(port=0, device=0)
+                Device._pin_factory.spi(port=0, device=0)
+    with patch('gpiozero.pins.local.SpiDev') as spidev:
+        with Device._pin_factory.spi(port=0, device=0) as spi:
+            with pytest.raises(GPIOPinInUse):
+                LED(11)
 
 def test_spi_hardware_read():
-    with mock.patch('gpiozero.spi.SpiDev') as spidev:
+    with patch('gpiozero.pins.local.SpiDev') as spidev:
         spidev.return_value.xfer2.side_effect = lambda data: list(range(10))[:len(data)]
-        with SPI() as device:
+        with Device._pin_factory.spi() as device:
             assert device.read(3) == [0, 1, 2]
             assert device.read(6) == list(range(6))
 
 def test_spi_hardware_write():
-    with mock.patch('gpiozero.spi.SpiDev') as spidev:
+    with patch('gpiozero.pins.local.SpiDev') as spidev:
         spidev.return_value.xfer2.side_effect = lambda data: list(range(10))[:len(data)]
-        with SPI() as device:
+        with Device._pin_factory.spi() as device:
             assert device.write([0, 1, 2]) == 3
             assert spidev.return_value.xfer2.called_with([0, 1, 2])
             assert device.write(list(range(6))) == 6
             assert spidev.return_value.xfer2.called_with(list(range(6)))
 
 def test_spi_hardware_modes():
-    with mock.patch('gpiozero.spi.SpiDev') as spidev:
+    with patch('gpiozero.pins.local.SpiDev') as spidev:
         spidev.return_value.mode = 0
         spidev.return_value.lsbfirst = False
         spidev.return_value.cshigh = True
         spidev.return_value.bits_per_word = 8
-        with SPI() as device:
+        with Device._pin_factory.spi() as device:
             assert device.clock_mode == 0
             assert not device.clock_polarity
             assert not device.clock_phase
@@ -116,7 +136,7 @@ def test_spi_software_read():
             super(SPISlave, self).on_start()
             for i in range(10):
                 self.tx_word(i)
-    with SPISlave(11, 10, 9, 8) as slave, SPI() as master:
+    with SPISlave(11, 10, 9, 8) as slave, Device._pin_factory.spi() as master:
         assert master.read(3) == [0, 1, 2]
         assert master.read(6) == [0, 1, 2, 3, 4, 5]
         slave.clock_phase = True
@@ -125,7 +145,7 @@ def test_spi_software_read():
         assert master.read(6) == [0, 1, 2, 3, 4, 5]
 
 def test_spi_software_write():
-    with MockSPIDevice(11, 10, 9, 8) as test_device, SPI() as master:
+    with MockSPIDevice(11, 10, 9, 8) as test_device, Device._pin_factory.spi() as master:
         master.write([0])
         assert test_device.rx_word() == 0
         master.write([2, 0])
@@ -134,7 +154,7 @@ def test_spi_software_write():
         assert test_device.rx_word() == 257
 
 def test_spi_software_clock_mode():
-    with SPI() as master:
+    with Device._pin_factory.spi() as master:
         assert master.clock_mode == 0
         assert not master.clock_polarity
         assert not master.clock_phase
@@ -151,7 +171,7 @@ def test_spi_software_clock_mode():
             master.clock_mode = 5
 
 def test_spi_software_attr():
-    with SPI() as master:
+    with Device._pin_factory.spi() as master:
         assert not master.lsb_first
         assert not master.select_high
         assert master.bits_per_word == 8

tests/test_spi_devices.py

@@ -15,16 +15,12 @@ try:
 except ImportError:
     from gpiozero.compat import isclose
 
-from gpiozero import *
 from gpiozero.pins.mock import MockSPIDevice, MockPin
+from gpiozero import *
 
 
-def setup_function(function):
-    import gpiozero.devices
-    gpiozero.devices.pin_factory = MockPin
-
 def teardown_function(function):
-    MockPin.clear_pins()
+    Device._pin_factory.reset()
 
 def clamp(v, min_value, max_value):
     return min(max_value, max(min_value, v))