1Kernel driver w83793
2====================
3
4Supported chips:
5
6  * Winbond W83793G/W83793R
7
8    Prefix: 'w83793'
9
10    Addresses scanned: I2C 0x2c - 0x2f
11
12    Datasheet: Still not published
13
14Authors:
15    - Yuan Mu (Winbond Electronics)
16    - Rudolf Marek <r.marek@assembler.cz>
17
18
19Module parameters
20-----------------
21
22* reset int
23    (default 0)
24
25    This parameter is not recommended, it will lose motherboard specific
26    settings. Use 'reset=1' to reset the chip when loading this module.
27
28* force_subclients=bus,caddr,saddr1,saddr2
29    This is used to force the i2c addresses for subclients of
30    a certain chip. Typical usage is `force_subclients=0,0x2f,0x4a,0x4b`
31    to force the subclients of chip 0x2f on bus 0 to i2c addresses
32    0x4a and 0x4b.
33
34
35Description
36-----------
37
38This driver implements support for Winbond W83793G/W83793R chips.
39
40* Exported features
41    This driver exports 10 voltage sensors, up to 12 fan tachometer inputs,
42    6 remote temperatures, up to 8 sets of PWM fan controls, SmartFan
43    (automatic fan speed control) on all temperature/PWM combinations, 2
44    sets of 6-pin CPU VID input.
45
46* Sensor resolutions
47    If your motherboard maker used the reference design, the resolution of
48    voltage0-2 is 2mV, resolution of voltage3/4/5 is 16mV, 8mV for voltage6,
49    24mV for voltage7/8. Temp1-4 have a 0.25 degree Celsius resolution,
50    temp5-6 have a 1 degree Celsiis resolution.
51
52* Temperature sensor types
53    Temp1-4 have 2 possible types. It can be read from (and written to)
54    temp[1-4]_type.
55
56    - If the value is 3, it starts monitoring using a remote termal diode
57      (default).
58    - If the value is 6, it starts monitoring using the temperature sensor
59      in Intel CPU and get result by PECI.
60
61    Temp5-6 can be connected to external thermistors (value of
62    temp[5-6]_type is 4).
63
64* Alarm mechanism
65    For voltage sensors, an alarm triggers if the measured value is below
66    the low voltage limit or over the high voltage limit.
67    For temperature sensors, an alarm triggers if the measured value goes
68    above the high temperature limit, and wears off only after the measured
69    value drops below the hysteresis value.
70    For fan sensors, an alarm triggers if the measured value is below the
71    low speed limit.
72
73* SmartFan/PWM control
74    If you want to set a pwm fan to manual mode, you just need to make sure it
75    is not controlled by any temp channel, for example, you want to set fan1
76    to manual mode, you need to check the value of temp[1-6]_fan_map, make
77    sure bit 0 is cleared in the 6 values. And then set the pwm1 value to
78    control the fan.
79
80    Each temperature channel can control all the 8 PWM outputs (by setting the
81    corresponding bit in tempX_fan_map), you can set the temperature channel
82    mode using temp[1-6]_pwm_enable, 2 is Thermal Cruise mode and 3
83    is the SmartFanII mode. Temperature channels will try to speed up or
84    slow down all controlled fans, this means one fan can receive different
85    PWM value requests from different temperature channels, but the chip
86    will always pick the safest (max) PWM value for each fan.
87
88    In Thermal Cruise mode, the chip attempts to keep the temperature at a
89    predefined value, within a tolerance margin. So if tempX_input >
90    thermal_cruiseX + toleranceX, the chip will increase the PWM value,
91    if tempX_input < thermal_cruiseX - toleranceX, the chip will decrease
92    the PWM value. If the temperature is within the tolerance range, the PWM
93    value is left unchanged.
94
95    SmartFanII works differently, you have to define up to 7 PWM, temperature
96    trip points, defining a PWM/temperature curve which the chip will follow.
97    While not fundamentally different from the Thermal Cruise mode, the
98    implementation is quite different, giving you a finer-grained control.
99
100* Chassis
101    If the case open alarm triggers, it will stay in this state unless cleared
102    by writing 0 to the sysfs file "intrusion0_alarm".
103
104* VID and VRM
105    The VRM version is detected automatically, don't modify the it unless you
106    *do* know the cpu VRM version and it's not properly detected.
107
108
109Notes
110-----
111
112  Only Fan1-5 and PWM1-3 are guaranteed to always exist, other fan inputs and
113  PWM outputs may or may not exist depending on the chip pin configuration.
114