currently selected). If you know the address of the chip, use a 'force'
parameter; this will put it into a more well-behaved state first.
-The driver implements three temperature sensors, five fan rotation speed
-sensors, and ten voltage sensors.
+The driver implements three temperature sensors, ten voltage sensors,
+five fan rotation speed sensors and manual PWM control of each fan.
Temperatures are measured in degrees Celsius and measurement resolution is 1
degC for temp1 and 0.5 degC for temp2 and temp3. An alarm is triggered when
the temperature gets higher than the Overtemperature Shutdown value; it stays
on until the temperature falls below the Hysteresis value.
+Voltage sensors (also known as IN sensors) report their values in millivolts.
+An alarm is triggered if the voltage has crossed a programmable minimum
+or maximum limit.
+
Fan rotation speeds are reported in RPM (rotations per minute). An alarm is
triggered if the rotation speed has dropped below a programmable limit. Fan
readings can be divided by a programmable divider (1, 2, 4, 8, 16,
32, 64 or 128 for all fans) to give the readings more range or accuracy.
-Voltage sensors (also known as IN sensors) report their values in millivolts.
-An alarm is triggered if the voltage has crossed a programmable minimum
-or maximum limit.
+Each fan controlled is controlled by PWM. The PWM duty cycle can be read and
+set for each fan separately. Valid values range from 0 (stop) to 255 (full).
+PWM 1-3 support Thermal Cruise mode, in which the PWMs are automatically
+regulated to keep respectively temp 1-3 at a certain target temperature.
+See below for the description of the sysfs-interface.
The w83791d has a global bit used to enable beeping from the speaker when an
alarm is triggered as well as a bitmask to enable or disable the beep for
specific alarms. You need both the global beep enable bit and the
corresponding beep bit to be on for a triggered alarm to sound a beep.
-The sysfs interface to the gloabal enable is via the sysfs beep_enable file.
+The sysfs interface to the global enable is via the sysfs beep_enable file.
This file is used for both legacy and new code.
The sysfs interface to the beep bitmask has migrated from the original legacy
method of a single sysfs beep_mask file to a newer method using multiple
*_beep files as described in .../Documentation/hwmon/sysfs-interface.
-A similar change has occured for the bitmap corresponding to the alarms. The
+A similar change has occurred for the bitmap corresponding to the alarms. The
original legacy method used a single sysfs alarms file containing a bitmap
of triggered alarms. The newer method uses multiple sysfs *_alarm files
(again following the pattern described in sysfs-interface).
The driver reads the hardware chip values at most once every three seconds.
User mode code requesting values more often will receive cached values.
+/sys files
+----------
+The sysfs-interface is documented in the 'sysfs-interface' file. Only
+chip-specific options are documented here.
+
+pwm[1-3]_enable - this file controls mode of fan/temperature control for
+ fan 1-3. Fan/PWM 4-5 only support manual mode.
+ * 1 Manual mode
+ * 2 Thermal Cruise mode
+ * 3 Fan Speed Cruise mode (no further support)
+
+temp[1-3]_target - defines the target temperature for Thermal Cruise mode.
+ Unit: millidegree Celsius
+ RW
+
+temp[1-3]_tolerance - temperature tolerance for Thermal Cruise mode.
+ Specifies an interval around the target temperature
+ in which the fan speed is not changed.
+ Unit: millidegree Celsius
+ RW
+
Alarms bitmap vs. beep_mask bitmask
------------------------------------
For legacy code using the alarms and beep_mask files:
tart3 : alarms: 0x040000 beep_mask: 0x100000 <== mismatch
case_open : alarms: 0x001000 beep_mask: 0x001000
global_enable: alarms: -------- beep_mask: 0x800000 (modified via beep_enable)
-
-W83791D TODO:
----------------
-Provide a patch for smart-fan control (still need appropriate motherboard/fans)
git.openpandora.org / pandora-kernel.git / blobdiff