hwmon: add support for Sensirion SHT3x sensors (7c84f7f8) · Commits · e / devices / android_kernel_fairphone_FP3

Documentation/hwmon/sht3x

0 → 100644

+72 −0

Original line number	Diff line number	Diff line
		Kernel driver sht3x
		===================

		Supported chips:
		* Sensirion SHT3x-DIS
		Prefix: 'sht3x'
		Addresses scanned: none
		Datasheet: http://www.sensirion.com/fileadmin/user_upload/customers/sensirion/Dokumente/Humidity/Sensirion_Humidity_Datasheet_SHT3x_DIS.pdf

		Author:
		David Frey <david.frey@sensirion.com>
		Pascal Sachs <pascal.sachs@sensirion.com>

		Description
		-----------

		This driver implements support for the Sensirion SHT3x-DIS chip, a humidity
		and temperature sensor. Temperature is measured in degrees celsius, relative
		humidity is expressed as a percentage. In the sysfs interface, all values are
		scaled by 1000, i.e. the value for 31.5 degrees celsius is 31500.

		The device communicates with the I2C protocol. Sensors can have the I2C
		addresses 0x44 or 0x45, depending on the wiring. See
		Documentation/i2c/instantiating-devices for methods to instantiate the device.

		There are two options configurable by means of sht3x_platform_data:
		1. blocking (pull the I2C clock line down while performing the measurement) or
		non-blocking mode. Blocking mode will guarantee the fastest result but
		the I2C bus will be busy during that time. By default, non-blocking mode
		is used. Make sure clock-stretching works properly on your device if you
		want to use blocking mode.
		2. high or low accuracy. High accuracy is used by default and using it is
		strongly recommended.

		The sht3x sensor supports a single shot mode as well as 5 periodic measure
		modes, which can be controlled with the update_interval sysfs interface.
		The allowed update_interval in milliseconds are as follows:
		* 0 single shot mode
		* 2000 0.5 Hz periodic measurement
		* 1000 1 Hz periodic measurement
		* 500 2 Hz periodic measurement
		* 250 4 Hz periodic measurement
		* 100 10 Hz periodic measurement

		In the periodic measure mode, the sensor automatically triggers a measurement
		with the configured update interval on the chip. When a temperature or humidity
		reading exceeds the configured limits, the alert attribute is set to 1 and
		the alert pin on the sensor is set to high.
		When the temperature and humidity readings move back between the hysteresis
		values, the alert bit is set to 0 and the alert pin on the sensor is set to
		low.

		sysfs-Interface
		---------------

		temp1_input: temperature input
		humidity1_input: humidity input
		temp1_max: temperature max value
		temp1_max_hyst: temperature hysteresis value for max limit
		humidity1_max: humidity max value
		humidity1_max_hyst: humidity hysteresis value for max limit
		temp1_min: temperature min value
		temp1_min_hyst: temperature hysteresis value for min limit
		humidity1_min: humidity min value
		humidity1_min_hyst: humidity hysteresis value for min limit
		temp1_alarm: alarm flag is set to 1 if the temperature is outside the
		configured limits. Alarm only works in periodic measure mode
		humidity1_alarm: alarm flag is set to 1 if the humidity is outside the
		configured limits. Alarm only works in periodic measure mode
		update_interval: update interval, 0 for single shot, interval in msec
		for periodic measurement. If the interval is not supported
		by the sensor, the next faster interval is chosen

drivers/hwmon/Kconfig

+11 −0

Original line number	Diff line number	Diff line
		@@ -1265,6 +1265,17 @@ config SENSORS_SHT21
		This driver can also be built as a module. If so, the module
		will be called sht21.

		config SENSORS_SHT3x
		tristate "Sensiron humidity and temperature sensors. SHT3x and compat."
		depends on I2C
		select CRC8
		help
		If you say yes here you get support for the Sensiron SHT30 and SHT31
		humidity and temperature sensors.

		This driver can also be built as a module. If so, the module
		will be called sht3x.

		config SENSORS_SHTC1
		tristate "Sensiron humidity and temperature sensors. SHTC1 and compat."
		depends on I2C

drivers/hwmon/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -138,6 +138,7 @@ obj-$(CONFIG_SENSORS_SCH5627) += sch5627.o
		obj-$(CONFIG_SENSORS_SCH5636) += sch5636.o
		obj-$(CONFIG_SENSORS_SHT15) += sht15.o
		obj-$(CONFIG_SENSORS_SHT21) += sht21.o
		obj-$(CONFIG_SENSORS_SHT3x) += sht3x.o
		obj-$(CONFIG_SENSORS_SHTC1) += shtc1.o
		obj-$(CONFIG_SENSORS_SIS5595) += sis5595.o
		obj-$(CONFIG_SENSORS_SMM665) += smm665.o

drivers/hwmon/sht3x.c

0 → 100644

+725 −0

File added.

Preview size limit exceeded, changes collapsed.

include/linux/platform_data/sht3x.h

0 → 100644

+25 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2016 Sensirion AG, Switzerland
		* Author: David Frey <david.frey@sensirion.com>
		* Author: Pascal Sachs <pascal.sachs@sensirion.com>
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License as published by
		* the Free Software Foundation; either version 2 of the License, or
		* (at your option) any later version.
		*
		* This program is distributed in the hope that it will be useful,
		* but WITHOUT ANY WARRANTY; without even the implied warranty of
		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
		* GNU General Public License for more details.
		*
		*/

		#ifndef __SHT3X_H_
		#define __SHT3X_H_

		struct sht3x_platform_data {
		bool blocking_io;
		bool high_precision;
		};
		#endif /* __SHT3X_H_ */