Fix #521

Rename pigpiod module to pigpio

gpiozero/pins/pigpio.py

@@ -0,0 +1,521 @@
+from __future__ import (
+    unicode_literals,
+    absolute_import,
+    print_function,
+    division,
+    )
+str = type('')
+
+import os
+from weakref import proxy
+
+import pigpio
+
+from . import SPI
+from .pi import PiPin, PiFactory, SPI_HARDWARE_PINS
+from .data import pi_info
+from ..devices import Device
+from ..mixins import SharedMixin
+from ..exc import (
+    PinInvalidFunction,
+    PinSetInput,
+    PinFixedPull,
+    PinInvalidPull,
+    PinInvalidBounce,
+    PinInvalidState,
+    SPIBadArgs,
+    SPIInvalidClockMode,
+    )
+
+
+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
+    access to the GPIO pins, and communicates with this daemon over a network
+    socket.
+
+    While this does mean only the daemon itself should control the pins, the
+    architecture does have several advantages:
+
+    * Pins can be remote controlled from another machine (the other
+      machine doesn't even have to be a Raspberry Pi; it simply needs the
+      `pigpio`_ client library installed on it)
+    * The daemon supports hardware PWM via the DMA controller
+    * Your script itself doesn't require root privileges; it just needs to
+      be able to communicate with the daemon
+
+    You can construct pigpio pins manually like so::
+
+        from gpiozero.pins.pigpio import PiGPIOPin
+        from gpiozero import LED
+
+        led = LED(PiGPIOPin(12))
+
+    This is particularly useful for controlling pins on a remote machine. To
+    accomplish this simply specify the host (and optionally port) when
+    constructing the pin::
+
+        from gpiozero.pins.pigpio import PiGPIOPin
+        from gpiozero import LED
+        from signal import pause
+
+        led = LED(PiGPIOPin(12, host='192.168.0.2'))
+
+    .. note::
+
+        In some circumstances, especially when playing with PWM, it does appear
+        to be possible to get the daemon into "unusual" states. We would be
+        most interested to hear any bug reports relating to this (it may be a
+        bug in our pin implementation). A workaround for now is simply to
+        restart the ``pigpiod`` daemon.
+
+    .. _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_classes = {
+            ('hardware', 'exclusive'): PiGPIOHardwareSPI,
+            ('hardware', 'shared'):    PiGPIOHardwareSPIShared,
+            ('software', 'exclusive'): PiGPIOSoftwareSPI,
+            ('software', 'shared'):    PiGPIOSoftwareSPIShared,
+            }
+        self._connection = pigpio.pi(host, port)
+        # Annoyingly, pigpio doesn't raise an exception when it fails to make a
+        # connection; it returns a valid (but disconnected) pi object
+        if self.connection is None:
+            raise IOError('failed to connect to %s:%s' % (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)
+    GPIO_FUNCTIONS = {
+        'input':   pigpio.INPUT,
+        'output':  pigpio.OUTPUT,
+        'alt0':    pigpio.ALT0,
+        'alt1':    pigpio.ALT1,
+        'alt2':    pigpio.ALT2,
+        'alt3':    pigpio.ALT3,
+        'alt4':    pigpio.ALT4,
+        'alt5':    pigpio.ALT5,
+        }
+
+    GPIO_PULL_UPS = {
+        'up':       pigpio.PUD_UP,
+        'down':     pigpio.PUD_DOWN,
+        'floating': pigpio.PUD_OFF,
+        }
+
+    GPIO_EDGES = {
+        'both':    pigpio.EITHER_EDGE,
+        'rising':  pigpio.RISING_EDGE,
+        'falling': pigpio.FALLING_EDGE,
+        }
+
+    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()}
+    GPIO_EDGES_NAMES = {v: k for (k, v) in GPIO_EDGES.items()}
+
+    def __init__(self, factory, number):
+        super(PiGPIOPin, self).__init__(factory, number)
+        self._pull = 'up' if factory.pi_info.pulled_up(self.address[-1]) else 'floating'
+        self._pwm = False
+        self._bounce = None
+        self._callback = None
+        self._edges = pigpio.EITHER_EDGE
+        try:
+            self.factory.connection.set_mode(self.number, pigpio.INPUT)
+        except pigpio.error as e:
+            raise ValueError(e)
+        self.factory.connection.set_pull_up_down(self.number, self.GPIO_PULL_UPS[self._pull])
+        self.factory.connection.set_glitch_filter(self.number, 0)
+
+    def close(self):
+        if self.factory.connection:
+            self.frequency = None
+            self.when_changed = None
+            self.function = 'input'
+            self.pull = 'up' if self.factory.pi_info.pulled_up(self.address[-1]) else 'floating'
+
+    def _get_function(self):
+        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.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.factory.connection.get_PWM_dutycycle(self.number) /
+                self.factory.connection.get_PWM_range(self.number)
+                )
+        else:
+            return bool(self.factory.connection.read(self.number))
+
+    def _set_state(self, value):
+        if self._pwm:
+            try:
+                value = int(value * self.factory.connection.get_PWM_range(self.number))
+                if value != self.factory.connection.get_PWM_dutycycle(self.number):
+                    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.factory.connection.write(self.number, bool(value))
+
+    def _get_pull(self):
+        return self._pull
+
+    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.factory.pi_info.pulled_up(self.address[-1]):
+            raise PinFixedPull('%r has a physical pull-up resistor' % self)
+        try:
+            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.factory.connection.get_PWM_frequency(self.number)
+        return None
+
+    def _set_frequency(self, value):
+        if not self._pwm and value is not None:
+            if self.function != 'output':
+                raise PinPWMFixedValue('cannot start PWM on pin %r' % self)
+            # NOTE: the pin's state *must* be set to zero; if it's currently
+            # high, starting PWM and setting a 0 duty-cycle *doesn't* bring
+            # the pin low; it stays high!
+            self.factory.connection.write(self.number, 0)
+            self.factory.connection.set_PWM_frequency(self.number, value)
+            self.factory.connection.set_PWM_range(self.number, 10000)
+            self.factory.connection.set_PWM_dutycycle(self.number, 0)
+            self._pwm = True
+        elif self._pwm and value is not None:
+            if value != self.factory.connection.get_PWM_frequency(self.number):
+                self.factory.connection.set_PWM_frequency(self.number, value)
+                self.factory.connection.set_PWM_range(self.number, 10000)
+        elif self._pwm and value is None:
+            self.factory.connection.write(self.number, 0)
+            self._pwm = False
+
+    def _get_bounce(self):
+        return None if not self._bounce else self._bounce / 1000000
+
+    def _set_bounce(self, value):
+        if value is None:
+            value = 0
+        elif value < 0:
+            raise PinInvalidBounce('bounce must be 0 or greater')
+        self.factory.connection.set_glitch_filter(self.number, int(value * 1000000))
+
+    def _get_edges(self):
+        return self.GPIO_EDGES_NAMES[self._edges]
+
+    def _set_edges(self, value):
+        f = self.when_changed
+        self.when_changed = None
+        try:
+            self._edges = self.GPIO_EDGES[value]
+        finally:
+            self.when_changed = f
+
+    def _call_when_changed(self, gpio, level, tick):
+        super(PiGPIOPin, self)._call_when_changed()
+
+    def _enable_event_detect(self):
+        self._callback = self.factory.connection.callback(
+                self.number, self._edges, self._call_when_changed)
+
+    def _disable_event_detect(self):
+        if self._callback is not None:
+            self._callback.cancel()
+            self._callback = None
+
+
+class PiGPIOHardwareSPI(SPI, Device):
+    def __init__(self, factory, port, device):
+        self._port = port
+        self._device = device
+        self._factory = proxy(factory)
+        self._handle = None
+        super(PiGPIOHardwareSPI, self).__init__()
+        pins = SPI_HARDWARE_PINS[port]
+        self._reserve_pins(*(
+            factory.address + ('GPIO%d' % pin,)
+            for pin in (
+                pins['clock'],
+                pins['mosi'],
+                pins['miso'],
+                pins['select'][device]
+            )
+        ))
+        self._spi_flags = 8 << 16
+        self._baud = 500000
+        self._handle = self._factory.connection.spi_open(
+            device, self._baud, self._spi_flags)
+
+    def _conflicts_with(self, other):
+        return not (
+            isinstance(other, PiGPIOHardwareSPI) and
+            (self._port, self._device) != (other._port, other._device)
+            )
+
+    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 _get_clock_mode(self):
+        return self._spi_flags & 0x3
+
+    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._spi_flags = (self._spi_flags & ~0x3) | value
+        self._handle = self._factory.connection.spi_open(
+            self._device, self._baud, self._spi_flags)
+
+    def _get_select_high(self):
+        return bool((self._spi_flags >> (2 + self._device)) & 0x1)
+
+    def _set_select_high(self, value):
+        self._check_open()
+        self._factory.connection.spi_close(self._handle)
+        self._spi_flags = (self._spi_flags & ~0x1c) | (bool(value) << (2 + self._device))
+        self._handle = self._factory.connection.spi_open(
+            self._device, self._baud, self._spi_flags)
+
+    def _get_bits_per_word(self):
+        return (self._spi_flags >> 16) & 0x3f
+
+    def _set_bits_per_word(self, value):
+        self._check_open()
+        self._factory.connection.spi_close(self._handle)
+        self._spi_flags = (self._spi_flags & ~0x3f0000) | ((value & 0x3f) << 16)
+        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._closed = True
+        self._select_pin = select_pin
+        self._clock_pin = clock_pin
+        self._mosi_pin = mosi_pin
+        self._miso_pin = miso_pin
+        self._factory = proxy(factory)
+        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._spi_flags = 0
+        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._closed = False
+        except:
+            self.close()
+            raise
+
+    def _conflicts_with(self, other):
+        return not (
+            isinstance(other, PiGPIOSoftwareSPI) and
+            (self._select_pin) != (other._select_pin)
+            )
+
+    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._closed = True
+            self._factory.connection.bb_spi_close(self._select_pin)
+        self._release_all()
+        super(PiGPIOSoftwareSPI, self).close()
+
+    @property
+    def closed(self):
+        return self._closed
+
+    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._spi_flags & 0x3
+
+    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._spi_flags = (self._spi_flags & ~0x3) | 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 bool(self._spi_flags & 0x4)
+
+    def _set_select_high(self, value):
+        self._check_open()
+        self._factory.connection.bb_spi_close(self._select_pin)
+        self._spi_flags = (self._spi_flags & ~0x4) | (bool(value) << 2)
+        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 bool(self._spi_flags & 0xc000)
+
+    def _set_lsb_first(self, value):
+        self._check_open()
+        self._factory.connection.bb_spi_close(self._select_pin)
+        self._spi_flags = (
+            (self._spi_flags & ~0xc000)
+            | (bool(value) << 14)
+            | (bool(value) << 15)
+            )
+        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)
+