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authorLinus Torvalds <torvalds@linux-foundation.org>2011-01-10 11:57:46 -0500
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-10 11:57:46 -0500
commita08948812b30653eb2c536ae613b635a989feb6f (patch)
tree7f648ea16caf9c210dcdd4f30e13648f51624830 /Documentation
parent0bd2cbcdfaff9cb22267d66fc843fa4f73f0c281 (diff)
parent6099469805c24af14250e182bb9ca082b8a6b716 (diff)
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 000000000000..1fbe3cd916cc
--- /dev/null
+++ b/Documentation/hwmon/ds620
@@ -0,0 +1,34 @@
1Kernel driver ds620
2===================
3
4Supported chips:
5 * Dallas Semiconductor DS620
6 Prefix: 'ds620'
7 Datasheet: Publicly available at the Dallas Semiconductor website
8 http://www.dalsemi.com/
9
10Authors:
11 Roland Stigge <stigge@antcom.de>
12 based on ds1621.c by
13 Christian W. Zuckschwerdt <zany@triq.net>
14
15Description
16-----------
17
18The DS620 is a (one instance) digital thermometer and thermostat. It has both
19high and low temperature limits which can be user defined (i.e. programmed
20into non-volatile on-chip registers). Temperature range is -55 degree Celsius
21to +125. Between 0 and 70 degree Celsius, accuracy is 0.5 Kelvin. The value
22returned via sysfs displays post decimal positions.
23
24The thermostat function works as follows: When configured via platform_data
25(struct ds620_platform_data) .pomode == 0 (default), the thermostat output pin
26PO is always low. If .pomode == 1, the thermostat is in PO_LOW mode. I.e., the
27output pin PO becomes active when the temperature falls below temp1_min and
28stays active until the temperature goes above temp1_max.
29
30Likewise, with .pomode == 2, the thermostat is in PO_HIGH mode. I.e., the PO
31output pin becomes active when the temperature goes above temp1_max and stays
32active until the temperature falls below temp1_min.
33
34The PO output pin of the DS620 operates active-low.
diff --git a/Documentation/hwmon/sht21 b/Documentation/hwmon/sht21
new file mode 100644
index 000000000000..db17fda45c3e
--- /dev/null
+++ b/Documentation/hwmon/sht21
@@ -0,0 +1,49 @@
1Kernel driver sht21
2===================
3
4Supported chips:
5 * Sensirion SHT21
6 Prefix: 'sht21'
7 Addresses scanned: none
8 Datasheet: Publicly available at the Sensirion website
9 http://www.sensirion.com/en/pdf/product_information/Datasheet-humidity-sensor-SHT21.pdf
10
11 * Sensirion SHT25
12 Prefix: 'sht21'
13 Addresses scanned: none
14 Datasheet: Publicly available at the Sensirion website
15 http://www.sensirion.com/en/pdf/product_information/Datasheet-humidity-sensor-SHT25.pdf
16
17Author:
18 Urs Fleisch <urs.fleisch@sensirion.com>
19
20Description
21-----------
22
23The SHT21 and SHT25 are humidity and temperature sensors in a DFN package of
24only 3 x 3 mm footprint and 1.1 mm height. The difference between the two
25devices is the higher level of precision of the SHT25 (1.8% relative humidity,
260.2 degree Celsius) compared with the SHT21 (2.0% relative humidity,
270.3 degree Celsius).
28
29The devices communicate with the I2C protocol. All sensors are set to the same
30I2C address 0x40, so an entry with I2C_BOARD_INFO("sht21", 0x40) can be used
31in the board setup code.
32
33sysfs-Interface
34---------------
35
36temp1_input - temperature input
37humidity1_input - humidity input
38
39Notes
40-----
41
42The driver uses the default resolution settings of 12 bit for humidity and 14
43bit for temperature, which results in typical measurement times of 22 ms for
44humidity and 66 ms for temperature. To keep self heating below 0.1 degree
45Celsius, the device should not be active for more than 10% of the time,
46e.g. maximum two measurements per second at the given resolution.
47
48Different resolutions, the on-chip heater, using the CRC checksum and reading
49the serial number are not supported yet.
diff --git a/Documentation/hwmon/sysfs-interface b/Documentation/hwmon/sysfs-interface
index 645699010551..c6559f153589 100644
--- a/Documentation/hwmon/sysfs-interface
+++ b/Documentation/hwmon/sysfs-interface
@@ -384,10 +384,20 @@ curr[1-*]_min Current min value.
384 Unit: milliampere 384 Unit: milliampere
385 RW 385 RW
386 386
387curr[1-*]_lcrit Current critical low value
388 Unit: milliampere
389 RW
390
391curr[1-*]_crit Current critical high value.
392 Unit: milliampere
393 RW
394
387curr[1-*]_input Current input value 395curr[1-*]_input Current input value
388 Unit: milliampere 396 Unit: milliampere
389 RO 397 RO
390 398
399Also see the Alarms section for status flags associated with currents.
400
391********* 401*********
392* Power * 402* Power *
393********* 403*********
@@ -450,13 +460,6 @@ power[1-*]_accuracy Accuracy of the power meter.
450 Unit: Percent 460 Unit: Percent
451 RO 461 RO
452 462
453power[1-*]_alarm 1 if the system is drawing more power than the
454 cap allows; 0 otherwise. A poll notification is
455 sent to this file when the power use exceeds the
456 cap. This file only appears if the cap is known
457 to be enforced by hardware.
458 RO
459
460power[1-*]_cap If power use rises above this limit, the 463power[1-*]_cap If power use rises above this limit, the
461 system should take action to reduce power use. 464 system should take action to reduce power use.
462 A poll notification is sent to this file if the 465 A poll notification is sent to this file if the
@@ -479,6 +482,20 @@ power[1-*]_cap_min Minimum cap that can be set.
479 Unit: microWatt 482 Unit: microWatt
480 RO 483 RO
481 484
485power[1-*]_max Maximum power.
486 Unit: microWatt
487 RW
488
489power[1-*]_crit Critical maximum power.
490 If power rises to or above this limit, the
491 system is expected take drastic action to reduce
492 power consumption, such as a system shutdown or
493 a forced powerdown of some devices.
494 Unit: microWatt
495 RW
496
497Also see the Alarms section for status flags associated with power readings.
498
482********** 499**********
483* Energy * 500* Energy *
484********** 501**********
@@ -488,6 +505,15 @@ energy[1-*]_input Cumulative energy use
488 RO 505 RO
489 506
490 507
508************
509* Humidity *
510************
511
512humidity[1-*]_input Humidity
513 Unit: milli-percent (per cent mille, pcm)
514 RO
515
516
491********** 517**********
492* Alarms * 518* Alarms *
493********** 519**********
@@ -501,6 +527,7 @@ implementation.
501 527
502in[0-*]_alarm 528in[0-*]_alarm
503curr[1-*]_alarm 529curr[1-*]_alarm
530power[1-*]_alarm
504fan[1-*]_alarm 531fan[1-*]_alarm
505temp[1-*]_alarm 532temp[1-*]_alarm
506 Channel alarm 533 Channel alarm
@@ -512,12 +539,20 @@ OR
512 539
513in[0-*]_min_alarm 540in[0-*]_min_alarm
514in[0-*]_max_alarm 541in[0-*]_max_alarm
542in[0-*]_lcrit_alarm
543in[0-*]_crit_alarm
515curr[1-*]_min_alarm 544curr[1-*]_min_alarm
516curr[1-*]_max_alarm 545curr[1-*]_max_alarm
546curr[1-*]_lcrit_alarm
547curr[1-*]_crit_alarm
548power[1-*]_cap_alarm
549power[1-*]_max_alarm
550power[1-*]_crit_alarm
517fan[1-*]_min_alarm 551fan[1-*]_min_alarm
518fan[1-*]_max_alarm 552fan[1-*]_max_alarm
519temp[1-*]_min_alarm 553temp[1-*]_min_alarm
520temp[1-*]_max_alarm 554temp[1-*]_max_alarm
555temp[1-*]_lcrit_alarm
521temp[1-*]_crit_alarm 556temp[1-*]_crit_alarm
522temp[1-*]_emergency_alarm 557temp[1-*]_emergency_alarm
523 Limit alarm 558 Limit alarm