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