From 849369d6c66d3054688672f97d31fceb8e8230fb Mon Sep 17 00:00:00 2001 From: root Date: Fri, 25 Dec 2015 04:40:36 +0000 Subject: initial_commit --- Documentation/hwmon/sht15 | 74 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+) create mode 100644 Documentation/hwmon/sht15 (limited to 'Documentation/hwmon/sht15') diff --git a/Documentation/hwmon/sht15 b/Documentation/hwmon/sht15 new file mode 100644 index 00000000..02850bdf --- /dev/null +++ b/Documentation/hwmon/sht15 @@ -0,0 +1,74 @@ +Kernel driver sht15 +=================== + +Authors: + * Wouter Horre + * Jonathan Cameron + * Vivien Didelot + * Jerome Oufella + +Supported chips: + * Sensirion SHT10 + Prefix: 'sht10' + + * Sensirion SHT11 + Prefix: 'sht11' + + * Sensirion SHT15 + Prefix: 'sht15' + + * Sensirion SHT71 + Prefix: 'sht71' + + * Sensirion SHT75 + Prefix: 'sht75' + +Datasheet: Publicly available at the Sensirion website +http://www.sensirion.ch/en/pdf/product_information/Datasheet-humidity-sensor-SHT1x.pdf + +Description +----------- + +The SHT10, SHT11, SHT15, SHT71, and SHT75 are humidity and temperature +sensors. + +The devices communicate using two GPIO lines. + +Supported resolutions for the measurements are 14 bits for temperature and 12 +bits for humidity, or 12 bits for temperature and 8 bits for humidity. + +The humidity calibration coefficients are programmed into an OTP memory on the +chip. These coefficients are used to internally calibrate the signals from the +sensors. Disabling the reload of those coefficients allows saving 10ms for each +measurement and decrease power consumption, while loosing on precision. + +Some options may be set directly in the sht15_platform_data structure +or via sysfs attributes. + +Notes: + * The regulator supply name is set to "vcc". + * If a CRC validation fails, a soft reset command is sent, which resets + status register to its hardware default value, but the driver will try to + restore the previous device configuration. + +Platform data +------------- + +* checksum: + set it to true to enable CRC validation of the readings (default to false). +* no_otp_reload: + flag to indicate not to reload from OTP (default to false). +* low_resolution: + flag to indicate the temp/humidity resolution to use (default to false). + +Sysfs interface +--------------- + +* temp1_input: temperature input +* humidity1_input: humidity input +* heater_enable: write 1 in this attribute to enable the on-chip heater, + 0 to disable it. Be careful not to enable the heater + for too long. +* temp1_fault: if 1, this means that the voltage is low (below 2.47V) and + measurement may be invalid. +* humidity1_fault: same as temp1_fault. -- cgit v1.2.3