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+Kernel driver w83793
+Supported chips:
+ * Winbond W83793G/W83793R
+ Prefix: 'w83793'
+ Addresses scanned: I2C 0x2c - 0x2f
+ Datasheet: Still not published
+ 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.
+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 2 possible types. It can be read from (and written to)
+ temp[1-4]_type.
+ - If the value is 3, it starts monitoring using a remote termal diode
+ (default).
+ - 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).
+* 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 writing 0 to the sysfs file "intrusion0_alarm".
+* 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.
+ 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.