Add RPi GPIO sensor

homeassistant/components/sensor/rpi_gpio.py

@@ -0,0 +1,130 @@
+# -*- coding: utf-8 -*-
+"""
+homeassistant.components.sensor.rpi_gpio
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Allows to configure a binary state sensor using RPi GPIO.
+Note: To use RPi GPIO, Home Assistant must be run as root.
+
+sensor:
+  platform: rpi_gpio
+  pull_mode: "UP"
+  value_high: "Active"
+  value_low: "Inactive"
+  ports:
+    11: PIR Office
+    12: PIR Bedroom
+
+Variables:
+
+pull_mode
+*Optional
+The internal pull to use (UP or DOWN). Default is UP.
+
+value_high
+*Optional
+The value of the sensor when the port is HIGH. Default is "HIGH".
+
+value_low
+*Optional
+The value of the sensor when the port is LOW. Default is "LOW".
+
+bouncetime
+*Optional
+The time in milliseconds for port debouncing. Default is 50ms.
+
+ports
+*Required
+An array specifying the GPIO ports to use and the name to use in the frontend.
+
+"""
+
+import logging
+from homeassistant.helpers.entity import Entity
+try:
+    import RPi.GPIO as GPIO
+except ImportError:
+    GPIO = None
+from homeassistant.const import (DEVICE_DEFAULT_NAME,
+                                 EVENT_HOMEASSISTANT_START,
+                                 EVENT_HOMEASSISTANT_STOP)
+
+DEFAULT_PULL_MODE = "UP"
+DEFAULT_VALUE_HIGH = "HIGH"
+DEFAULT_VALUE_LOW = "LOW"
+DEFAULT_BOUNCETIME = 50
+
+REQUIREMENTS = ['RPi.GPIO>=0.5.11']
+_LOGGER = logging.getLogger(__name__)
+
+
+# pylint: disable=unused-argument
+def setup_platform(hass, config, add_devices, discovery_info=None):
+    """ Sets up the Raspberry PI GPIO ports. """
+    if GPIO is None:
+        _LOGGER.error('RPi.GPIO not available. rpi_gpio ports ignored.')
+        return
+
+    GPIO.setmode(GPIO.BCM)
+
+    sensors = []
+    pull_mode = config.get('pull_mode', DEFAULT_PULL_MODE)
+    value_high = config.get('value_high', DEFAULT_VALUE_HIGH)
+    value_low = config.get('value_low', DEFAULT_VALUE_LOW)
+    bouncetime = config.get('bouncetime', DEFAULT_BOUNCETIME)
+    ports = config.get('ports')
+    for port_num, port_name in ports.items():
+        sensors.append(RPiGPIOSensor(
+            port_name, port_num, pull_mode,
+            value_high, value_low, bouncetime))
+    add_devices(sensors)
+
+    def cleanup_gpio(event):
+        """ Stuff to do before stop home assistant. """
+        # pylint: disable=no-member
+        GPIO.cleanup()
+
+    def prepare_gpio(event):
+        """ Stuff to do when home assistant starts. """
+        hass.bus.listen_once(EVENT_HOMEASSISTANT_STOP, cleanup_gpio)
+
+    hass.bus.listen_once(EVENT_HOMEASSISTANT_START, prepare_gpio)
+
+
+class RPiGPIOSensor(Entity):
+    """ Sets up the Raspberry PI GPIO ports. """
+    def __init__(self, port_name, port_num, pull_mode,
+                 value_high, value_low, bouncetime):
+        self._name = port_name
+        self._port = port_num
+        self._pull = GPIO.PUD_DOWN if pull_mode=="DOWN" else GPIO.PUD_UP
+        self._vhigh = value_high
+        self._vlow = value_low
+        self._bouncetime = bouncetime
+        GPIO.setup(self._port, GPIO.IN, pull_up_down=self._pull)
+        self._state = self._vhigh if GPIO.input(self._port) else self._vlow
+
+        def edge_callback(channel):
+            """ port changed state """
+            self._state = self._vhigh if GPIO.input(channel) else self._vlow
+            self.update_ha_state()
+
+        GPIO.add_event_detect(
+            self._port,
+            GPIO.BOTH,
+            callback=edge_callback,
+            bouncetime=self._bouncetime)
+
+    @property
+    def should_poll(self):
+        """ No polling needed """
+        return False
+
+    @property
+    def name(self):
+        """ The name of the sensor """
+        return self._name
+
+    @property
+    def state(self):
+        """ Returns the state of the entity. """
+        return self._state