mirror of
https://github.com/torvalds/linux.git
synced 2024-11-17 09:31:50 +00:00
657c93b10f
Signed-off-by: David Hubbard <david.c.hubbard@gmail.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
126 lines
5.2 KiB
Plaintext
126 lines
5.2 KiB
Plaintext
Kernel driver w83627ehf
|
|
=======================
|
|
|
|
Supported chips:
|
|
* Winbond W83627EHF/EHG/DHG (ISA access ONLY)
|
|
Prefix: 'w83627ehf'
|
|
Addresses scanned: ISA address retrieved from Super I/O registers
|
|
Datasheet:
|
|
http://www.winbond-usa.com/products/winbond_products/pdfs/PCIC/W83627EHF_%20W83627EHGb.pdf
|
|
DHG datasheet confidential.
|
|
|
|
Authors:
|
|
Jean Delvare <khali@linux-fr.org>
|
|
Yuan Mu (Winbond)
|
|
Rudolf Marek <r.marek@assembler.cz>
|
|
David Hubbard <david.c.hubbard@gmail.com>
|
|
|
|
Description
|
|
-----------
|
|
|
|
This driver implements support for the Winbond W83627EHF, W83627EHG, and
|
|
W83627DHG super I/O chips. We will refer to them collectively as Winbond chips.
|
|
|
|
The chips implement three temperature sensors, five fan rotation
|
|
speed sensors, ten analog voltage sensors (only nine for the 627DHG), alarms
|
|
with beep warnings (control unimplemented), and some automatic fan regulation
|
|
strategies (plus manual fan control mode).
|
|
|
|
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 high limit; 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. The driver sets the most
|
|
suitable fan divisor itself. Some fans might not be present because they
|
|
share pins with other functions.
|
|
|
|
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.
|
|
|
|
The driver supports automatic fan control mode known as Thermal Cruise.
|
|
In this mode, the chip attempts to keep the measured temperature in a
|
|
predefined temperature range. If the temperature goes out of range, fan
|
|
is driven slower/faster to reach the predefined range again.
|
|
|
|
The mode works for fan1-fan4. Mapping of temperatures to pwm outputs is as
|
|
follows:
|
|
|
|
temp1 -> pwm1
|
|
temp2 -> pwm2
|
|
temp3 -> pwm3
|
|
prog -> pwm4 (the programmable setting is not supported by the driver)
|
|
|
|
/sys files
|
|
----------
|
|
|
|
name - this is a standard hwmon device entry. For the W83627EHF and W83627EHG,
|
|
it is set to "w83627ehf" and for the W83627DHG it is set to "w83627dhg"
|
|
|
|
pwm[1-4] - this file stores PWM duty cycle or DC value (fan speed) in range:
|
|
0 (stop) to 255 (full)
|
|
|
|
pwm[1-4]_enable - this file controls mode of fan/temperature control:
|
|
* 1 Manual Mode, write to pwm file any value 0-255 (full speed)
|
|
* 2 Thermal Cruise
|
|
|
|
Thermal Cruise mode
|
|
-------------------
|
|
|
|
If the temperature is in the range defined by:
|
|
|
|
pwm[1-4]_target - set target temperature, unit millidegree Celsius
|
|
(range 0 - 127000)
|
|
pwm[1-4]_tolerance - tolerance, unit millidegree Celsius (range 0 - 15000)
|
|
|
|
there are no changes to fan speed. Once the temperature leaves the interval,
|
|
fan speed increases (temp is higher) or decreases if lower than desired.
|
|
There are defined steps and times, but not exported by the driver yet.
|
|
|
|
pwm[1-4]_min_output - minimum fan speed (range 1 - 255), when the temperature
|
|
is below defined range.
|
|
pwm[1-4]_stop_time - how many milliseconds [ms] must elapse to switch
|
|
corresponding fan off. (when the temperature was below
|
|
defined range).
|
|
|
|
Note: last two functions are influenced by other control bits, not yet exported
|
|
by the driver, so a change might not have any effect.
|
|
|
|
Implementation Details
|
|
----------------------
|
|
|
|
Future driver development should bear in mind that the following registers have
|
|
different functions on the 627EHF and the 627DHG. Some registers also have
|
|
different power-on default values, but BIOS should already be loading
|
|
appropriate defaults. Note that bank selection must be performed as is currently
|
|
done in the driver for all register addresses.
|
|
|
|
0x49: only on DHG, selects temperature source for AUX fan, CPU fan0
|
|
0x4a: not completely documented for the EHF and the DHG documentation assigns
|
|
different behavior to bits 7 and 6, including extending the temperature
|
|
input selection to SmartFan I, not just SmartFan III. Testing on the EHF
|
|
will reveal whether they are compatible or not.
|
|
|
|
0x58: Chip ID: 0xa1=EHF 0xc1=DHG
|
|
0x5e: only on DHG, has bits to enable "current mode" temperature detection and
|
|
critical temperature protection
|
|
0x45b: only on EHF, bit 3, vin4 alarm (EHF supports 10 inputs, only 9 on DHG)
|
|
0x552: only on EHF, vin4
|
|
0x558: only on EHF, vin4 high limit
|
|
0x559: only on EHF, vin4 low limit
|
|
0x6b: only on DHG, SYS fan critical temperature
|
|
0x6c: only on DHG, CPU fan0 critical temperature
|
|
0x6d: only on DHG, AUX fan critical temperature
|
|
0x6e: only on DHG, CPU fan1 critical temperature
|
|
|
|
0x50-0x55 and 0x650-0x657 are marked "Test Register" for the EHF, but "Reserved
|
|
Register" for the DHG
|
|
|
|
The DHG also supports PECI, where the DHG queries Intel CPU temperatures, and
|
|
the ICH8 southbridge gets that data via PECI from the DHG, so that the
|
|
southbridge drives the fans. And the DHG supports SST, a one-wire serial bus.
|