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author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-01-10 08:57:46 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-01-10 08:57:46 -0800 |
commit | a08948812b30653eb2c536ae613b635a989feb6f (patch) | |
tree | 7f648ea16caf9c210dcdd4f30e13648f51624830 /Documentation | |
parent | 0bd2cbcdfaff9cb22267d66fc843fa4f73f0c281 (diff) | |
parent | 6099469805c24af14250e182bb9ca082b8a6b716 (diff) | |
download | kernel_samsung_espresso10-a08948812b30653eb2c536ae613b635a989feb6f.zip kernel_samsung_espresso10-a08948812b30653eb2c536ae613b635a989feb6f.tar.gz kernel_samsung_espresso10-a08948812b30653eb2c536ae613b635a989feb6f.tar.bz2 |
Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/staging
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/staging: (44 commits)
hwmon: Support for Dallas Semiconductor DS620
hwmon: driver for Sensirion SHT21 humidity and temperature sensor
hwmon: Add humidity attribute to sysfs ABI
hwmon: sysfs ABI updates
hwmon: (via-cputemp) sync hotplug handling with coretemp/pkgtemp
hwmon: (lm95241) Rewrite to avoid using macros
hwmon: (applesmc) Fix checkpatch errors and fix value range checks
hwmon: (applesmc) Update copyright information
hwmon: (applesmc) Silence driver
hwmon: (applesmc) Simplify feature sysfs handling
hwmon: (applesmc) Dynamic creation of fan files
hwmon: (applesmc) Extract all features generically
hwmon: (applesmc) Handle new temperature format
hwmon: (applesmc) Dynamic creation of temperature files
hwmon: (applesmc) Introduce a register lookup table
hwmon: (applesmc) Use pr_fmt and pr_<level>
hwmon: (applesmc) Relax the severity of device init failure
hwmon: (applesmc) Add MacBookAir3,1(3,2) support
hwmon: (w83627hf) Use pr_fmt and pr_<level>
hwmon: (w83627ehf) Use pr_fmt and pr_<level>
...
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/hwmon/ds620 | 34 | ||||
-rw-r--r-- | Documentation/hwmon/sht21 | 49 | ||||
-rw-r--r-- | Documentation/hwmon/sysfs-interface | 49 |
3 files changed, 125 insertions, 7 deletions
diff --git a/Documentation/hwmon/ds620 b/Documentation/hwmon/ds620 new file mode 100644 index 0000000..1fbe3cd --- /dev/null +++ b/Documentation/hwmon/ds620 @@ -0,0 +1,34 @@ +Kernel driver ds620 +=================== + +Supported chips: + * Dallas Semiconductor DS620 + Prefix: 'ds620' + Datasheet: Publicly available at the Dallas Semiconductor website + http://www.dalsemi.com/ + +Authors: + Roland Stigge <stigge@antcom.de> + based on ds1621.c by + Christian W. Zuckschwerdt <zany@triq.net> + +Description +----------- + +The DS620 is a (one instance) digital thermometer and thermostat. It has both +high and low temperature limits which can be user defined (i.e. programmed +into non-volatile on-chip registers). Temperature range is -55 degree Celsius +to +125. Between 0 and 70 degree Celsius, accuracy is 0.5 Kelvin. The value +returned via sysfs displays post decimal positions. + +The thermostat function works as follows: When configured via platform_data +(struct ds620_platform_data) .pomode == 0 (default), the thermostat output pin +PO is always low. If .pomode == 1, the thermostat is in PO_LOW mode. I.e., the +output pin PO becomes active when the temperature falls below temp1_min and +stays active until the temperature goes above temp1_max. + +Likewise, with .pomode == 2, the thermostat is in PO_HIGH mode. I.e., the PO +output pin becomes active when the temperature goes above temp1_max and stays +active until the temperature falls below temp1_min. + +The PO output pin of the DS620 operates active-low. diff --git a/Documentation/hwmon/sht21 b/Documentation/hwmon/sht21 new file mode 100644 index 0000000..db17fda --- /dev/null +++ b/Documentation/hwmon/sht21 @@ -0,0 +1,49 @@ +Kernel driver sht21 +=================== + +Supported chips: + * Sensirion SHT21 + Prefix: 'sht21' + Addresses scanned: none + Datasheet: Publicly available at the Sensirion website + http://www.sensirion.com/en/pdf/product_information/Datasheet-humidity-sensor-SHT21.pdf + + * Sensirion SHT25 + Prefix: 'sht21' + Addresses scanned: none + Datasheet: Publicly available at the Sensirion website + http://www.sensirion.com/en/pdf/product_information/Datasheet-humidity-sensor-SHT25.pdf + +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 + +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, using the CRC checksum and reading +the serial number are not supported yet. diff --git a/Documentation/hwmon/sysfs-interface b/Documentation/hwmon/sysfs-interface index 6456990..c6559f1 100644 --- a/Documentation/hwmon/sysfs-interface +++ b/Documentation/hwmon/sysfs-interface @@ -384,10 +384,20 @@ curr[1-*]_min Current min value. Unit: milliampere RW +curr[1-*]_lcrit Current critical low value + Unit: milliampere + RW + +curr[1-*]_crit Current critical high value. + Unit: milliampere + RW + curr[1-*]_input Current input value Unit: milliampere RO +Also see the Alarms section for status flags associated with currents. + ********* * Power * ********* @@ -450,13 +460,6 @@ power[1-*]_accuracy Accuracy of the power meter. Unit: Percent RO -power[1-*]_alarm 1 if the system is drawing more power than the - cap allows; 0 otherwise. A poll notification is - sent to this file when the power use exceeds the - cap. This file only appears if the cap is known - to be enforced by hardware. - RO - power[1-*]_cap If power use rises above this limit, the system should take action to reduce power use. A poll notification is sent to this file if the @@ -479,6 +482,20 @@ power[1-*]_cap_min Minimum cap that can be set. Unit: microWatt RO +power[1-*]_max Maximum power. + Unit: microWatt + RW + +power[1-*]_crit Critical maximum power. + If power rises to or above this limit, the + system is expected take drastic action to reduce + power consumption, such as a system shutdown or + a forced powerdown of some devices. + Unit: microWatt + RW + +Also see the Alarms section for status flags associated with power readings. + ********** * Energy * ********** @@ -488,6 +505,15 @@ energy[1-*]_input Cumulative energy use RO +************ +* Humidity * +************ + +humidity[1-*]_input Humidity + Unit: milli-percent (per cent mille, pcm) + RO + + ********** * Alarms * ********** @@ -501,6 +527,7 @@ implementation. in[0-*]_alarm curr[1-*]_alarm +power[1-*]_alarm fan[1-*]_alarm temp[1-*]_alarm Channel alarm @@ -512,12 +539,20 @@ OR in[0-*]_min_alarm in[0-*]_max_alarm +in[0-*]_lcrit_alarm +in[0-*]_crit_alarm curr[1-*]_min_alarm curr[1-*]_max_alarm +curr[1-*]_lcrit_alarm +curr[1-*]_crit_alarm +power[1-*]_cap_alarm +power[1-*]_max_alarm +power[1-*]_crit_alarm fan[1-*]_min_alarm fan[1-*]_max_alarm temp[1-*]_min_alarm temp[1-*]_max_alarm +temp[1-*]_lcrit_alarm temp[1-*]_crit_alarm temp[1-*]_emergency_alarm Limit alarm |