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authorMauro Carvalho Chehab <mchehab+samsung@kernel.org>2019-04-17 12:46:29 +0300
committerGuenter Roeck <linux@roeck-us.net>2019-04-17 20:37:23 +0300
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tree9db30159bd32bec125c7d49e80a79bb7c4da0c8e /Documentation/hwmon/sht21.rst
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downloadlinux-7ebd8b66dd9e5a0b65e5ee5e2b8e7ca382ec97b7.tar.xz
docs: hwmon: Add an index file and rename docs to *.rst
Now that all files were converted to ReST format, rename them and add an index. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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+Kernel driver sht21
+===================
+
+Supported chips:
+
+ * Sensirion SHT21
+
+ Prefix: 'sht21'
+
+ Addresses scanned: none
+
+ Datasheet: Publicly available at the Sensirion website
+
+ http://www.sensirion.com/file/datasheet_sht21
+
+
+
+ * Sensirion SHT25
+
+ Prefix: 'sht25'
+
+ Addresses scanned: none
+
+ Datasheet: Publicly available at the Sensirion website
+
+ http://www.sensirion.com/file/datasheet_sht25
+
+
+
+Author:
+
+ Urs Fleisch <urs.fleisch@sensirion.com>
+
+Description
+-----------
+
+The SHT21 and SHT25 are humidity and temperature sensors in a DFN package of
+only 3 x 3 mm footprint and 1.1 mm height. The difference between the two
+devices is the higher level of precision of the SHT25 (1.8% relative humidity,
+0.2 degree Celsius) compared with the SHT21 (2.0% relative humidity,
+0.3 degree Celsius).
+
+The devices communicate with the I2C protocol. All sensors are set to the same
+I2C address 0x40, so an entry with I2C_BOARD_INFO("sht21", 0x40) can be used
+in the board setup code.
+
+sysfs-Interface
+---------------
+
+temp1_input
+ - temperature input
+
+humidity1_input
+ - humidity input
+eic
+ - Electronic Identification Code
+
+Notes
+-----
+
+The driver uses the default resolution settings of 12 bit for humidity and 14
+bit for temperature, which results in typical measurement times of 22 ms for
+humidity and 66 ms for temperature. To keep self heating below 0.1 degree
+Celsius, the device should not be active for more than 10% of the time,
+e.g. maximum two measurements per second at the given resolution.
+
+Different resolutions, the on-chip heater, and using the CRC checksum
+are not supported yet.