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diff --git a/Documentation/hwmon/w83793 b/Documentation/hwmon/w83793 new file mode 100644 index 000000000000..45e5408340e0 --- /dev/null +++ b/Documentation/hwmon/w83793 @@ -0,0 +1,110 @@ +Kernel driver w83793 +==================== + +Supported chips: + * Winbond W83793G/W83793R + Prefix: 'w83793' + Addresses scanned: I2C 0x2c - 0x2f + Datasheet: Still not published + +Authors: + Yuan Mu (Winbond Electronics) + Rudolf Marek <r.marek@assembler.cz> + + +Module parameters +----------------- + +* reset int + (default 0) + This parameter is not recommended, it will lose motherboard specific + settings. Use 'reset=1' to reset the chip when loading this module. + +* force_subclients=bus,caddr,saddr1,saddr2 + This is used to force the i2c addresses for subclients of + a certain chip. Typical 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 Winbond W83793G/W83793R chips. + +* Exported features + This driver exports 10 voltage sensors, up to 12 fan tachometer inputs, + 6 remote temperatures, up to 8 sets of PWM fan controls, SmartFan + (automatic fan speed control) on all temperature/PWM combinations, 2 + sets of 6-pin CPU VID input. + +* Sensor resolutions + If your motherboard maker used the reference design, the resolution of + voltage0-2 is 2mV, resolution of voltage3/4/5 is 16mV, 8mV for voltage6, + 24mV for voltage7/8. Temp1-4 have a 0.25 degree Celsius resolution, + temp5-6 have a 1 degree Celsiis resolution. + +* Temperature sensor types + Temp1-4 have 3 possible types. It can be read from (and written to) + temp[1-4]_type. + - If the value of 0, the related temperature channel stops + monitoring. + - If the value is 3, it starts monitoring using a remote termal diode + (default). + - If the value is 5, it starts monitoring using the temperature sensor + in AMD CPU and get result by AMDSI. + - If the value is 6, it starts monitoring using the temperature sensor + in Intel CPU and get result by PECI. + Temp5-6 can be connected to external thermistors (value of + temp[5-6]_type is 4). They can also be disabled (value is 0). + +* Alarm mechanism + For voltage sensors, an alarm triggers if the measured value is below + the low voltage limit or over the high voltage limit. + For temperature sensors, an alarm triggers if the measured value goes + above the high temperature limit, and wears off only after the measured + value drops below the hysteresis value. + For fan sensors, an alarm triggers if the measured value is below the + low speed limit. + +* SmartFan/PWM control + If you want to set a pwm fan to manual mode, you just need to make sure it + is not controlled by any temp channel, for example, you want to set fan1 + to manual mode, you need to check the value of temp[1-6]_fan_map, make + sure bit 0 is cleared in the 6 values. And then set the pwm1 value to + control the fan. + + Each temperature channel can control all the 8 PWM outputs (by setting the + corresponding bit in tempX_fan_map), you can set the temperature channel + mode using temp[1-6]_pwm_enable, 2 is Thermal Cruise mode and 3 + is the SmartFanII mode. Temperature channels will try to speed up or + slow down all controlled fans, this means one fan can receive different + PWM value requests from different temperature channels, but the chip + will always pick the safest (max) PWM value for each fan. + + In Thermal Cruise mode, the chip attempts to keep the temperature at a + predefined value, within a tolerance margin. So if tempX_input > + thermal_cruiseX + toleranceX, the chip will increase the PWM value, + if tempX_input < thermal_cruiseX - toleranceX, the chip will decrease + the PWM value. If the temperature is within the tolerance range, the PWM + value is left unchanged. + + SmartFanII works differently, you have to define up to 7 PWM, temperature + trip points, defining a PWM/temperature curve which the chip will follow. + While not fundamentally different from the Thermal Cruise mode, the + implementation is quite different, giving you a finer-grained control. + +* Chassis + If the case open alarm triggers, it will stay in this state unless cleared + by any write to the sysfs file "chassis". + +* VID and VRM + The VRM version is detected automatically, don't modify the it unless you + *do* know the cpu VRM version and it's not properly detected. + + +Notes +----- + + Only Fan1-5 and PWM1-3 are guaranteed to always exist, other fan inputs and + PWM outputs may or may not exist depending on the chip pin configuration. |