Add new BH1750 light level sensor (#8050)

* new sensor platform
* requirements_all and .coveragerc update

.coveragerc

@@ -378,6 +378,7 @@ omit =
     homeassistant/components/sensor/arest.py
     homeassistant/components/sensor/arwn.py
     homeassistant/components/sensor/bbox.py
+    homeassistant/components/sensor/bh1750.py
     homeassistant/components/sensor/bitcoin.py
     homeassistant/components/sensor/blockchain.py
     homeassistant/components/sensor/bme280.py

homeassistant/components/sensor/bh1750.py

+"""
+Support for BH1750 light sensor.
+
+For more details about this platform, please refer to the documentation at
+https://home-assistant.io/components/sensor.bh1750/
+"""
+import asyncio
+from functools import partial
+import logging
+
+import voluptuous as vol
+
+from homeassistant.components.sensor import PLATFORM_SCHEMA
+import homeassistant.helpers.config_validation as cv
+from homeassistant.const import CONF_NAME
+from homeassistant.helpers.entity import Entity
+
+REQUIREMENTS = ['i2csense==0.0.3',
+                'smbus-cffi==0.5.1']
+
+_LOGGER = logging.getLogger(__name__)
+
+CONF_I2C_ADDRESS = 'i2c_address'
+CONF_I2C_BUS = 'i2c_bus'
+CONF_OPERATION_MODE = 'operation_mode'
+CONF_SENSITIVITY = 'sensitivity'
+CONF_DELAY = 'measurement_delay_ms'
+CONF_MULTIPLIER = 'multiplier'
+
+# Operation modes for BH1750 sensor (from the datasheet). Time typically 120ms
+# In one time measurements, device is set to Power Down after each sample.
+CONTINUOUS_LOW_RES_MODE = "continuous_low_res_mode"
+CONTINUOUS_HIGH_RES_MODE_1 = "continuous_high_res_mode_1"
+CONTINUOUS_HIGH_RES_MODE_2 = "continuous_high_res_mode_2"
+ONE_TIME_LOW_RES_MODE = "one_time_low_res_mode"
+ONE_TIME_HIGH_RES_MODE_1 = "one_time_high_res_mode_1"
+ONE_TIME_HIGH_RES_MODE_2 = "one_time_high_res_mode_2"
+OPERATION_MODES = {
+    CONTINUOUS_LOW_RES_MODE: (0x13, True),  # 4lx resolution
+    CONTINUOUS_HIGH_RES_MODE_1: (0x10, True),  # 1lx resolution.
+    CONTINUOUS_HIGH_RES_MODE_2: (0X11, True),  # 0.5lx resolution.
+    ONE_TIME_LOW_RES_MODE: (0x23, False),  # 4lx resolution.
+    ONE_TIME_HIGH_RES_MODE_1: (0x20, False),  # 1lx resolution.
+    ONE_TIME_HIGH_RES_MODE_2: (0x21, False),  # 0.5lx resolution.
+}
+
+SENSOR_UNIT = 'lx'
+DEFAULT_NAME = 'BH1750 Light Sensor'
+DEFAULT_I2C_ADDRESS = '0x23'
+DEFAULT_I2C_BUS = 1
+DEFAULT_MODE = CONTINUOUS_HIGH_RES_MODE_1
+DEFAULT_DELAY_MS = 120
+DEFAULT_SENSITIVITY = 69  # from 31 to 254
+
+PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({
+    vol.Optional(CONF_NAME, default=DEFAULT_NAME): cv.string,
+    vol.Optional(CONF_I2C_ADDRESS, default=DEFAULT_I2C_ADDRESS): cv.string,
+    vol.Optional(CONF_I2C_BUS, default=DEFAULT_I2C_BUS): vol.Coerce(int),
+    vol.Optional(CONF_OPERATION_MODE, default=DEFAULT_MODE):
+        vol.In(OPERATION_MODES),
+    vol.Optional(CONF_SENSITIVITY, default=DEFAULT_SENSITIVITY):
+        cv.positive_int,
+    vol.Optional(CONF_DELAY, default=DEFAULT_DELAY_MS): cv.positive_int,
+    vol.Optional(CONF_MULTIPLIER, default=1.): vol.Range(min=0.1, max=10),
+})
+
+
+# pylint: disable=import-error
+@asyncio.coroutine
+def async_setup_platform(hass, config, async_add_devices, discovery_info=None):
+    """Set up the BH1750 sensor."""
+    import smbus
+    from i2csense.bh1750 import BH1750
+
+    name = config.get(CONF_NAME)
+    bus_number = config.get(CONF_I2C_BUS)
+    i2c_address = config.get(CONF_I2C_ADDRESS)
+    operation_mode = config.get(CONF_OPERATION_MODE)
+
+    bus = smbus.SMBus(bus_number)
+
+    sensor = yield from hass.async_add_job(
+        partial(BH1750, bus, i2c_address,
+                operation_mode=operation_mode,
+                measurement_delay=config.get(CONF_DELAY),
+                sensitivity=config.get(CONF_SENSITIVITY),
+                logger=_LOGGER)
+    )
+    if not sensor.sample_ok:
+        _LOGGER.error("BH1750 sensor not detected at %s", i2c_address)
+        return False
+
+    dev = [BH1750Sensor(sensor, name, SENSOR_UNIT,
+                        config.get(CONF_MULTIPLIER))]
+    _LOGGER.info("Setup of BH1750 light sensor at %s in mode %s is complete.",
+                 i2c_address, operation_mode)
+
+    async_add_devices(dev)
+
+
+class BH1750Sensor(Entity):
+    """Implementation of the BH1750 sensor."""
+
+    def __init__(self, bh1750_sensor, name, unit, multiplier=1.):
+        """Initialize the sensor."""
+        self._name = name
+        self._unit_of_measurement = unit
+        self._multiplier = multiplier
+        self.bh1750_sensor = bh1750_sensor
+        if self.bh1750_sensor.light_level >= 0:
+            self._state = int(round(self.bh1750_sensor.light_level))
+        else:
+            self._state = None
+
+    @property
+    def name(self) -> str:
+        """Return the name of the sensor."""
+        return self._name
+
+    @property
+    def state(self) -> int:
+        """Return the state of the sensor."""
+        return self._state
+
+    @property
+    def unit_of_measurement(self) -> str:
+        """Return the unit of measurement of the sensor."""
+        return self._unit_of_measurement
+
+    @property
+    def device_class(self) -> str:
+        """Return the class of this device, from component DEVICE_CLASSES."""
+        return 'light'
+
+    @asyncio.coroutine
+    def async_update(self):
+        """Get the latest data from the BH1750 and update the states."""
+        yield from self.hass.async_add_job(self.bh1750_sensor.update)
+        if self.bh1750_sensor.sample_ok \
+                and self.bh1750_sensor.light_level >= 0:
+            self._state = int(round(self.bh1750_sensor.light_level
+                                    * self._multiplier))
+        else:
+            _LOGGER.warning("Bad Update of sensor.%s: %s",
+                            self.name, self.bh1750_sensor.light_level)

requirements_all.txt

@@ -315,6 +315,7 @@ https://github.com/wmalgadey/PyTado/archive/0.1.10.zip#PyTado==0.1.10
 # homeassistant.components.media_player.lg_netcast
 https://github.com/wokar/pylgnetcast/archive/v0.2.0.zip#pylgnetcast==0.2.0
 
+# homeassistant.components.sensor.bh1750
 # homeassistant.components.sensor.bme280
 # homeassistant.components.sensor.htu21d
 # i2csense==0.0.3
@@ -822,6 +823,7 @@ sleekxmpp==1.3.2
 # homeassistant.components.sleepiq
 sleepyq==0.6
 
+# homeassistant.components.sensor.bh1750
 # homeassistant.components.sensor.bme280
 # homeassistant.components.sensor.envirophat
 # homeassistant.components.sensor.htu21d