mirror of
https://github.com/torvalds/linux.git
synced 2024-11-29 23:51:37 +00:00
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>
281 lines
8.4 KiB
ReStructuredText
281 lines
8.4 KiB
ReStructuredText
Kernel driver NCT6775
|
|
=====================
|
|
|
|
.. note::
|
|
|
|
This driver supersedes the NCT6775F and NCT6776F support in the W83627EHF
|
|
driver.
|
|
|
|
Supported chips:
|
|
|
|
* Nuvoton NCT6102D/NCT6104D/NCT6106D
|
|
|
|
Prefix: 'nct6106'
|
|
|
|
Addresses scanned: ISA address retrieved from Super I/O registers
|
|
|
|
Datasheet: Available from the Nuvoton web site
|
|
|
|
* Nuvoton NCT5572D/NCT6771F/NCT6772F/NCT6775F/W83677HG-I
|
|
|
|
Prefix: 'nct6775'
|
|
|
|
Addresses scanned: ISA address retrieved from Super I/O registers
|
|
|
|
Datasheet: Available from Nuvoton upon request
|
|
|
|
* Nuvoton NCT5573D/NCT5577D/NCT6776D/NCT6776F
|
|
|
|
Prefix: 'nct6776'
|
|
|
|
Addresses scanned: ISA address retrieved from Super I/O registers
|
|
|
|
Datasheet: Available from Nuvoton upon request
|
|
|
|
* Nuvoton NCT5532D/NCT6779D
|
|
|
|
Prefix: 'nct6779'
|
|
|
|
Addresses scanned: ISA address retrieved from Super I/O registers
|
|
|
|
Datasheet: Available from Nuvoton upon request
|
|
|
|
* Nuvoton NCT6791D
|
|
|
|
Prefix: 'nct6791'
|
|
|
|
Addresses scanned: ISA address retrieved from Super I/O registers
|
|
|
|
Datasheet: Available from Nuvoton upon request
|
|
|
|
* Nuvoton NCT6792D
|
|
|
|
Prefix: 'nct6792'
|
|
|
|
Addresses scanned: ISA address retrieved from Super I/O registers
|
|
|
|
Datasheet: Available from Nuvoton upon request
|
|
|
|
* Nuvoton NCT6793D
|
|
|
|
Prefix: 'nct6793'
|
|
|
|
Addresses scanned: ISA address retrieved from Super I/O registers
|
|
|
|
Datasheet: Available from Nuvoton upon request
|
|
|
|
* Nuvoton NCT6795D
|
|
|
|
Prefix: 'nct6795'
|
|
|
|
Addresses scanned: ISA address retrieved from Super I/O registers
|
|
|
|
Datasheet: Available from Nuvoton upon request
|
|
|
|
* Nuvoton NCT6796D
|
|
|
|
Prefix: 'nct6796'
|
|
|
|
Addresses scanned: ISA address retrieved from Super I/O registers
|
|
|
|
Datasheet: Available from Nuvoton upon request
|
|
|
|
|
|
|
|
Authors:
|
|
|
|
Guenter Roeck <linux@roeck-us.net>
|
|
|
|
Description
|
|
-----------
|
|
|
|
This driver implements support for the Nuvoton NCT6775F, NCT6776F, and NCT6779D
|
|
and compatible super I/O chips.
|
|
|
|
The chips support up to 25 temperature monitoring sources. Up to 6 of those are
|
|
direct temperature sensor inputs, the others are special sources such as PECI,
|
|
PCH, and SMBUS. Depending on the chip type, 2 to 6 of the temperature sources
|
|
can be monitored and compared against minimum, maximum, and critical
|
|
temperatures. The driver reports up to 10 of the temperatures to the user.
|
|
There are 4 to 5 fan rotation speed sensors, 8 to 15 analog voltage sensors,
|
|
one VID, alarms with beep warnings (control unimplemented), and some automatic
|
|
fan regulation strategies (plus manual fan control mode).
|
|
|
|
The temperature sensor sources on all chips are configurable. The configured
|
|
source for each of the temperature sensors is provided in tempX_label.
|
|
|
|
Temperatures are measured in degrees Celsius and measurement resolution is
|
|
either 1 degC or 0.5 degC, depending on the temperature source and
|
|
configuration. An alarm is triggered when the temperature gets higher than
|
|
the high limit; it stays on until the temperature falls below the hysteresis
|
|
value. Alarms are only supported for temp1 to temp6, depending on the chip type.
|
|
|
|
Fan rotation speeds are reported in RPM (rotations per minute). An alarm is
|
|
triggered if the rotation speed has dropped below a programmable limit. On
|
|
NCT6775F, 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 other chips
|
|
do not have a fan speed divider. The driver sets the most suitable fan divisor
|
|
itself; specifically, it increases the divider value each time a fan speed
|
|
reading returns an invalid value, and it reduces it if the fan speed reading
|
|
is lower than optimal. 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-fan5.
|
|
|
|
sysfs attributes
|
|
----------------
|
|
|
|
pwm[1-7]
|
|
- this file stores PWM duty cycle or DC value (fan speed) in range:
|
|
|
|
0 (lowest speed) to 255 (full)
|
|
|
|
pwm[1-7]_enable
|
|
- this file controls mode of fan/temperature control:
|
|
|
|
* 0 Fan control disabled (fans set to maximum speed)
|
|
* 1 Manual mode, write to pwm[0-5] any value 0-255
|
|
* 2 "Thermal Cruise" mode
|
|
* 3 "Fan Speed Cruise" mode
|
|
* 4 "Smart Fan III" mode (NCT6775F only)
|
|
* 5 "Smart Fan IV" mode
|
|
|
|
pwm[1-7]_mode
|
|
- controls if output is PWM or DC level
|
|
|
|
* 0 DC output
|
|
* 1 PWM output
|
|
|
|
Common fan control attributes
|
|
-----------------------------
|
|
|
|
pwm[1-7]_temp_sel
|
|
Temperature source. Value is temperature sensor index.
|
|
For example, select '1' for temp1_input.
|
|
|
|
pwm[1-7]_weight_temp_sel
|
|
Secondary temperature source. Value is temperature
|
|
sensor index. For example, select '1' for temp1_input.
|
|
Set to 0 to disable secondary temperature control.
|
|
|
|
If secondary temperature functionality is enabled, it is controlled with the
|
|
following attributes.
|
|
|
|
pwm[1-7]_weight_duty_step
|
|
Duty step size.
|
|
|
|
pwm[1-7]_weight_temp_step
|
|
Temperature step size. With each step over
|
|
temp_step_base, the value of weight_duty_step is added
|
|
to the current pwm value.
|
|
|
|
pwm[1-7]_weight_temp_step_base
|
|
Temperature at which secondary temperature control kicks
|
|
in.
|
|
|
|
pwm[1-7]_weight_temp_step_tol
|
|
Temperature step tolerance.
|
|
|
|
Thermal Cruise mode (2)
|
|
-----------------------
|
|
|
|
If the temperature is in the range defined by:
|
|
|
|
pwm[1-7]_target_temp
|
|
Target temperature, unit millidegree Celsius
|
|
(range 0 - 127000)
|
|
|
|
pwm[1-7]_temp_tolerance
|
|
Target temperature tolerance, unit millidegree Celsius
|
|
|
|
There are no changes to fan speed. Once the temperature leaves the interval, fan
|
|
speed increases (if temperature is higher that desired) or decreases (if
|
|
temperature is lower than desired), using the following limits and time
|
|
intervals.
|
|
|
|
pwm[1-7]_start
|
|
fan pwm start value (range 1 - 255), to start fan
|
|
when the temperature is above defined range.
|
|
|
|
pwm[1-7]_floor
|
|
lowest fan pwm (range 0 - 255) if temperature is below
|
|
the defined range. If set to 0, the fan is expected to
|
|
stop if the temperature is below the defined range.
|
|
|
|
pwm[1-7]_step_up_time
|
|
milliseconds before fan speed is increased
|
|
|
|
pwm[1-7]_step_down_time
|
|
milliseconds before fan speed is decreased
|
|
|
|
pwm[1-7]_stop_time
|
|
how many milliseconds must elapse to switch
|
|
corresponding fan off (when the temperature was below
|
|
defined range).
|
|
|
|
Speed Cruise mode (3)
|
|
---------------------
|
|
|
|
This modes tries to keep the fan speed constant.
|
|
|
|
fan[1-7]_target
|
|
Target fan speed
|
|
|
|
fan[1-7]_tolerance
|
|
Target speed tolerance
|
|
|
|
|
|
Untested; use at your own risk.
|
|
|
|
Smart Fan IV mode (5)
|
|
---------------------
|
|
|
|
This mode offers multiple slopes to control the fan speed. The slopes can be
|
|
controlled by setting the pwm and temperature attributes. When the temperature
|
|
rises, the chip will calculate the DC/PWM output based on the current slope.
|
|
There are up to seven data points depending on the chip type. Subsequent data
|
|
points should be set to higher temperatures and higher pwm values to achieve
|
|
higher fan speeds with increasing temperature. The last data point reflects
|
|
critical temperature mode, in which the fans should run at full speed.
|
|
|
|
pwm[1-7]_auto_point[1-7]_pwm
|
|
pwm value to be set if temperature reaches matching
|
|
temperature range.
|
|
|
|
pwm[1-7]_auto_point[1-7]_temp
|
|
Temperature over which the matching pwm is enabled.
|
|
|
|
pwm[1-7]_temp_tolerance
|
|
Temperature tolerance, unit millidegree Celsius
|
|
|
|
pwm[1-7]_crit_temp_tolerance
|
|
Temperature tolerance for critical temperature,
|
|
unit millidegree Celsius
|
|
|
|
pwm[1-7]_step_up_time
|
|
milliseconds before fan speed is increased
|
|
|
|
pwm[1-7]_step_down_time
|
|
milliseconds before fan speed is decreased
|
|
|
|
Usage Notes
|
|
-----------
|
|
|
|
On various ASUS boards with NCT6776F, it appears that CPUTIN is not really
|
|
connected to anything and floats, or that it is connected to some non-standard
|
|
temperature measurement device. As a result, the temperature reported on CPUTIN
|
|
will not reflect a usable value. It often reports unreasonably high
|
|
temperatures, and in some cases the reported temperature declines if the actual
|
|
temperature increases (similar to the raw PECI temperature value - see PECI
|
|
specification for details). CPUTIN should therefore be be ignored on ASUS
|
|
boards. The CPU temperature on ASUS boards is reported from PECI 0.
|