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  Kernel driver sht15
  ===================
  
  Authors:
    * Wouter Horre
    * Jonathan Cameron
    * Vivien Didelot <vivien.didelot@savoirfairelinux.com>
    * Jerome Oufella <jerome.oufella@savoirfairelinux.com>
  
  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 losing 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.