mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-27 14:43:58 +08:00
7ebd8b66dd
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>
200 lines
6.1 KiB
ReStructuredText
200 lines
6.1 KiB
ReStructuredText
Kernel driver w83792d
|
|
=====================
|
|
|
|
Supported chips:
|
|
|
|
* Winbond W83792D
|
|
|
|
Prefix: 'w83792d'
|
|
|
|
Addresses scanned: I2C 0x2c - 0x2f
|
|
|
|
Datasheet: http://www.winbond.com.tw
|
|
|
|
Author: Shane Huang (Winbond)
|
|
Updated: Roger Lucas
|
|
|
|
|
|
Module Parameters
|
|
-----------------
|
|
|
|
* init int
|
|
(default 1)
|
|
|
|
Use 'init=0' to bypass initializing the chip.
|
|
Try this if your computer crashes when you load the module.
|
|
|
|
* force_subclients=bus,caddr,saddr,saddr
|
|
This is used to force the i2c addresses for subclients of
|
|
a certain chip. Example usage is `force_subclients=0,0x2f,0x4a,0x4b`
|
|
to force the subclients of chip 0x2f on bus 0 to i2c addresses
|
|
0x4a and 0x4b.
|
|
|
|
|
|
Description
|
|
-----------
|
|
|
|
This driver implements support for the Winbond W83792AD/D.
|
|
|
|
Detection of the chip can sometimes be foiled because it can be in an
|
|
internal state that allows no clean access (Bank with ID register is not
|
|
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, seven fan rotation speed
|
|
sensors, nine voltage sensors, and two automatic fan regulation
|
|
strategies called: Smart Fan I (Thermal Cruise mode) and Smart Fan II.
|
|
|
|
The driver also implements up to seven fan control outputs: pwm1-7. Pwm1-7
|
|
can be configured to PWM output or Analogue DC output via their associated
|
|
pwmX_mode. Outputs pwm4 through pwm7 may or may not be present depending on
|
|
how the W83792AD/D was configured by the BIOS.
|
|
|
|
Automatic fan control mode is possible only for fan1-fan3.
|
|
|
|
For all pwmX outputs, a value of 0 means minimum fan speed and a value of
|
|
255 means maximum fan speed.
|
|
|
|
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.
|
|
|
|
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) 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.
|
|
|
|
Alarms are provided as output from "realtime status register". Following bits
|
|
are defined:
|
|
|
|
==== ==========
|
|
bit alarm on
|
|
==== ==========
|
|
0 in0
|
|
1 in1
|
|
2 temp1
|
|
3 temp2
|
|
4 temp3
|
|
5 fan1
|
|
6 fan2
|
|
7 fan3
|
|
8 in2
|
|
9 in3
|
|
10 in4
|
|
11 in5
|
|
12 in6
|
|
13 VID change
|
|
14 chassis
|
|
15 fan7
|
|
16 tart1
|
|
17 tart2
|
|
18 tart3
|
|
19 in7
|
|
20 in8
|
|
21 fan4
|
|
22 fan5
|
|
23 fan6
|
|
==== ==========
|
|
|
|
Tart will be asserted while target temperature cannot be achieved after 3 minutes
|
|
of full speed rotation of corresponding fan.
|
|
|
|
In addition to the alarms described above, there is a CHAS alarm on the chips
|
|
which triggers if your computer case is open (This one is latched, contrary
|
|
to realtime alarms).
|
|
|
|
The chips only update values each 3 seconds; reading them more often will
|
|
do no harm, but will return 'old' values.
|
|
|
|
|
|
W83792D PROBLEMS
|
|
----------------
|
|
Known problems:
|
|
- This driver is only for Winbond W83792D C version device, there
|
|
are also some motherboards with B version W83792D device. The
|
|
calculation method to in6-in7(measured value, limits) is a little
|
|
different between C and B version. C or B version can be identified
|
|
by CR[0x49h].
|
|
- The function of vid and vrm has not been finished, because I'm NOT
|
|
very familiar with them. Adding support is welcome.
|
|
- The function of chassis open detection needs more tests.
|
|
- If you have ASUS server board and chip was not found: Then you will
|
|
need to upgrade to latest (or beta) BIOS. If it does not help please
|
|
contact us.
|
|
|
|
Fan control
|
|
-----------
|
|
|
|
Manual mode
|
|
-----------
|
|
|
|
Works as expected. You just need to specify desired PWM/DC value (fan speed)
|
|
in appropriate pwm# file.
|
|
|
|
Thermal cruise
|
|
--------------
|
|
|
|
In this mode, W83792D provides the Smart Fan system to automatically control
|
|
fan speed to keep the temperatures of CPU and the system within specific
|
|
range. At first a wanted temperature and interval must be set. This is done
|
|
via thermal_cruise# file. The tolerance# file serves to create T +- tolerance
|
|
interval. The fan speed will be lowered as long as the current temperature
|
|
remains below the thermal_cruise# +- tolerance# value. Once the temperature
|
|
exceeds the high limit (T+tolerance), the fan will be turned on with a
|
|
specific speed set by pwm# and automatically controlled its PWM duty cycle
|
|
with the temperature varying. Three conditions may occur:
|
|
|
|
(1) If the temperature still exceeds the high limit, PWM duty
|
|
cycle will increase slowly.
|
|
|
|
(2) If the temperature goes below the high limit, but still above the low
|
|
limit (T-tolerance), the fan speed will be fixed at the current speed because
|
|
the temperature is in the target range.
|
|
|
|
(3) If the temperature goes below the low limit, PWM duty cycle will decrease
|
|
slowly to 0 or a preset stop value until the temperature exceeds the low
|
|
limit. (The preset stop value handling is not yet implemented in driver)
|
|
|
|
Smart Fan II
|
|
------------
|
|
|
|
W83792D also provides a special mode for fan. Four temperature points are
|
|
available. When related temperature sensors detects the temperature in preset
|
|
temperature region (sf2_point@_fan# +- tolerance#) it will cause fans to run
|
|
on programmed value from sf2_level@_fan#. You need to set four temperatures
|
|
for each fan.
|
|
|
|
|
|
/sys files
|
|
----------
|
|
|
|
pwm[1-7]
|
|
- this file stores PWM duty cycle or DC value (fan speed) in range:
|
|
|
|
0 (stop) to 255 (full)
|
|
pwm[1-3]_enable
|
|
- this file controls mode of fan/temperature control:
|
|
|
|
* 0 Disabled
|
|
* 1 Manual mode
|
|
* 2 Smart Fan II
|
|
* 3 Thermal Cruise
|
|
pwm[1-7]_mode
|
|
- Select PWM or DC mode
|
|
|
|
* 0 DC
|
|
* 1 PWM
|
|
thermal_cruise[1-3]
|
|
- Selects the desired temperature for cruise (degC)
|
|
tolerance[1-3]
|
|
- Value in degrees of Celsius (degC) for +- T
|
|
sf2_point[1-4]_fan[1-3]
|
|
- four temperature points for each fan for Smart Fan II
|
|
sf2_level[1-3]_fan[1-3]
|
|
- three PWM/DC levels for each fan for Smart Fan II
|