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author | Mauro Carvalho Chehab <mchehab+samsung@kernel.org> | 2019-04-17 12:46:29 +0300 |
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committer | Guenter Roeck <linux@roeck-us.net> | 2019-04-17 20:37:23 +0300 |
commit | 7ebd8b66dd9e5a0b65e5ee5e2b8e7ca382ec97b7 (patch) | |
tree | 9db30159bd32bec125c7d49e80a79bb7c4da0c8e /Documentation/hwmon/sht21.rst | |
parent | b04f2f7d387b3160883c2a1f5e2285483a791e82 (diff) | |
download | linux-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>
Diffstat (limited to 'Documentation/hwmon/sht21.rst')
-rw-r--r-- | Documentation/hwmon/sht21.rst | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/Documentation/hwmon/sht21.rst b/Documentation/hwmon/sht21.rst new file mode 100644 index 000000000000..f1f5da030108 --- /dev/null +++ b/Documentation/hwmon/sht21.rst @@ -0,0 +1,68 @@ +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. |