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Based on kernel version 2.6.33. Page generated on 2010-02-24 15:36 EST.

1	Kernel driver f71882fg
2	======================
3	
4	Supported chips:
5	  * Fintek F71858FG
6	    Prefix: 'f71858fg'
7	    Addresses scanned: none, address read from Super I/O config space
8	    Datasheet: Available from the Fintek website
9	  * Fintek F71862FG and F71863FG
10	    Prefix: 'f71862fg'
11	    Addresses scanned: none, address read from Super I/O config space
12	    Datasheet: Available from the Fintek website
13	  * Fintek F71882FG and F71883FG
14	    Prefix: 'f71882fg'
15	    Addresses scanned: none, address read from Super I/O config space
16	    Datasheet: Available from the Fintek website
17	  * Fintek F71889FG
18	    Prefix: 'f71889fg'
19	    Addresses scanned: none, address read from Super I/O config space
20	    Datasheet: Should become available on the Fintek website soon
21	  * Fintek F8000
22	    Prefix: 'f8000'
23	    Addresses scanned: none, address read from Super I/O config space
24	    Datasheet: Not public
25	
26	Author: Hans de Goede <hdegoede[AT]redhat[DOT]com>
27	
28	
29	Description
30	-----------
31	
32	Fintek F718xxFG/F8000 Super I/O chips include complete hardware monitoring
33	capabilities. They can monitor up to 9 voltages (3 for the F8000), 4 fans and
34	3 temperature sensors.
35	
36	These chips also have fan controlling features, using either DC or PWM, in
37	three different modes (one manual, two automatic).
38	
39	The driver assumes that no more than one chip is present, which seems
40	reasonable.
41	
42	
43	Monitoring
44	----------
45	
46	The Voltage, Fan and Temperature Monitoring uses the standard sysfs
47	interface as documented in sysfs-interface, without any exceptions.
48	
49	
50	Fan Control
51	-----------
52	
53	Both PWM (pulse-width modulation) and DC fan speed control methods are
54	supported. The right one to use depends on external circuitry on the
55	motherboard, so the driver assumes that the BIOS set the method
56	properly.
57	
58	Note that the lowest numbered temperature zone trip point corresponds to
59	to the border between the highest and one but highest temperature zones, and
60	vica versa. So the temperature zone trip points 1-4 (or 1-2) go from high temp
61	to low temp! This is how things are implemented in the IC, and the driver
62	mimicks this.
63	
64	There are 2 modes to specify the speed of the fan, PWM duty cycle (or DC
65	voltage) mode, where 0-100% duty cycle (0-100% of 12V) is specified. And RPM
66	mode where the actual RPM of the fan (as measured) is controlled and the speed
67	gets specified as 0-100% of the fan#_full_speed file.
68	
69	Since both modes work in a 0-100% (mapped to 0-255) scale, there isn't a
70	whole lot of a difference when modifying fan control settings. The only
71	important difference is that in RPM mode the 0-100% controls the fan speed
72	between 0-100% of fan#_full_speed. It is assumed that if the BIOS programs
73	RPM mode, it will also set fan#_full_speed properly, if it does not then
74	fan control will not work properly, unless you set a sane fan#_full_speed
75	value yourself.
76	
77	Switching between these modes requires re-initializing a whole bunch of
78	registers, so the mode which the BIOS has set is kept. The mode is
79	printed when loading the driver.
80	
81	Three different fan control modes are supported; the mode number is written
82	to the pwm#_enable file. Note that not all modes are supported on all
83	chips, and some modes may only be available in RPM / PWM mode.
84	Writing an unsupported mode will result in an invalid parameter error.
85	
86	* 1: Manual mode
87	  You ask for a specific PWM duty cycle / DC voltage or a specific % of
88	  fan#_full_speed by writing to the pwm# file. This mode is only
89	  available on the F71858FG / F8000 if the fan channel is in RPM mode.
90	
91	* 2: Normal auto mode
92	  You can define a number of temperature/fan speed trip points, which % the
93	  fan should run at at this temp and which temp a fan should follow using the
94	  standard sysfs interface. The number and type of trip points is chip
95	  depended, see which files are available in sysfs.
96	  Fan/PWM channel 3 of the F8000 is always in this mode!
97	
98	* 3: Thermostat mode (Only available on the F8000 when in duty cycle mode)
99	  The fan speed is regulated to keep the temp the fan is mapped to between
100	  temp#_auto_point2_temp and temp#_auto_point3_temp.
101	
102	Both of the automatic modes require that pwm1 corresponds to fan1, pwm2 to
103	fan2 and pwm3 to fan3.
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