diff --git a/docs/images/gpio_device_hierarchy.pdf b/docs/images/gpio_device_hierarchy.pdf
index 66ce3e1..8b7e9fa 100644
Binary files a/docs/images/gpio_device_hierarchy.pdf and b/docs/images/gpio_device_hierarchy.pdf differ
diff --git a/docs/images/gpio_device_hierarchy.png b/docs/images/gpio_device_hierarchy.png
index 8af9cbd..7c9ca57 100644
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