sht15 1.9 KB

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  1. Kernel driver sht15
  2. ===================
  3. Authors:
  4. * Wouter Horre
  5. * Jonathan Cameron
  6. * Vivien Didelot <vivien.didelot@savoirfairelinux.com>
  7. Supported chips:
  8. * Sensirion SHT10
  9. Prefix: 'sht10'
  10. * Sensirion SHT11
  11. Prefix: 'sht11'
  12. * Sensirion SHT15
  13. Prefix: 'sht15'
  14. * Sensirion SHT71
  15. Prefix: 'sht71'
  16. * Sensirion SHT75
  17. Prefix: 'sht75'
  18. Datasheet: Publicly available at the Sensirion website
  19. http://www.sensirion.ch/en/pdf/product_information/Datasheet-humidity-sensor-SHT1x.pdf
  20. Description
  21. -----------
  22. The SHT10, SHT11, SHT15, SHT71, and SHT75 are humidity and temperature
  23. sensors.
  24. The devices communicate using two GPIO lines.
  25. Supported resolutions for the measurements are 14 bits for temperature and 12
  26. bits for humidity, or 12 bits for temperature and 8 bits for humidity.
  27. The humidity calibration coefficients are programmed into an OTP memory on the
  28. chip. These coefficients are used to internally calibrate the signals from the
  29. sensors. Disabling the reload of those coefficients allows saving 10ms for each
  30. measurement and decrease power consumption, while loosing on precision.
  31. Some options may be set directly in the sht15_platform_data structure
  32. or via sysfs attributes.
  33. Note: The regulator supply name is set to "vcc".
  34. Platform data
  35. -------------
  36. * no_otp_reload:
  37. flag to indicate not to reload from OTP (default to false).
  38. * low_resolution:
  39. flag to indicate the temp/humidity resolution to use (default to false).
  40. Sysfs interface
  41. ---------------
  42. * temp1_input: temperature input
  43. * humidity1_input: humidity input
  44. * heater_enable: write 1 in this attribute to enable the on-chip heater,
  45. 0 to disable it. Be careful not to enable the heater
  46. for too long.
  47. * temp1_fault: if 1, this means that the voltage is low (below 2.47V) and
  48. measurement may be invalid.
  49. * humidity1_fault: same as temp1_fault.