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authorLinus Torvalds <torvalds@linux-foundation.org>2011-01-10 08:57:46 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-10 08:57:46 -0800
commita08948812b30653eb2c536ae613b635a989feb6f (patch)
tree7f648ea16caf9c210dcdd4f30e13648f51624830 /Documentation
parent0bd2cbcdfaff9cb22267d66fc843fa4f73f0c281 (diff)
parent6099469805c24af14250e182bb9ca082b8a6b716 (diff)
downloadop-kernel-dev-a08948812b30653eb2c536ae613b635a989feb6f.zip
op-kernel-dev-a08948812b30653eb2c536ae613b635a989feb6f.tar.gz
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/ds62034
-rw-r--r--Documentation/hwmon/sht2149
-rw-r--r--Documentation/hwmon/sysfs-interface49
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
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