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Based on kernel version 3.13. Page generated on 2014-01-20 22:03 EST.

1	Kernel driver f71882fg
2	======================
3	
4	Supported chips:
5	  * Fintek F71808E
6	    Prefix: 'f71808e'
7	    Addresses scanned: none, address read from Super I/O config space
8	    Datasheet: Not public
9	  * Fintek F71808A
10	    Prefix: 'f71808a'
11	    Addresses scanned: none, address read from Super I/O config space
12	    Datasheet: Not public
13	  * Fintek F71858FG
14	    Prefix: 'f71858fg'
15	    Addresses scanned: none, address read from Super I/O config space
16	    Datasheet: Available from the Fintek website
17	  * Fintek F71862FG and F71863FG
18	    Prefix: 'f71862fg'
19	    Addresses scanned: none, address read from Super I/O config space
20	    Datasheet: Available from the Fintek website
21	  * Fintek F71869F and F71869E
22	    Prefix: 'f71869'
23	    Addresses scanned: none, address read from Super I/O config space
24	    Datasheet: Available from the Fintek website
25	  * Fintek F71869A
26	    Prefix: 'f71869a'
27	    Addresses scanned: none, address read from Super I/O config space
28	    Datasheet: Not public
29	  * Fintek F71882FG and F71883FG
30	    Prefix: 'f71882fg'
31	    Addresses scanned: none, address read from Super I/O config space
32	    Datasheet: Available from the Fintek website
33	  * Fintek F71889FG
34	    Prefix: 'f71889fg'
35	    Addresses scanned: none, address read from Super I/O config space
36	    Datasheet: Available from the Fintek website
37	  * Fintek F71889ED
38	    Prefix: 'f71889ed'
39	    Addresses scanned: none, address read from Super I/O config space
40	    Datasheet: Should become available on the Fintek website soon
41	  * Fintek F71889A
42	    Prefix: 'f71889a'
43	    Addresses scanned: none, address read from Super I/O config space
44	    Datasheet: Should become available on the Fintek website soon
45	  * Fintek F8000
46	    Prefix: 'f8000'
47	    Addresses scanned: none, address read from Super I/O config space
48	    Datasheet: Not public
49	  * Fintek F81801U
50	    Prefix: 'f71889fg'
51	    Addresses scanned: none, address read from Super I/O config space
52	    Datasheet: Not public
53	    Note: This is the 64-pin variant of the F71889FG, they have the
54		  same device ID and are fully compatible as far as hardware
55		  monitoring is concerned.
56	  * Fintek F81865F
57	    Prefix: 'f81865f'
58	    Addresses scanned: none, address read from Super I/O config space
59	    Datasheet: Available from the Fintek website
60	
61	Author: Hans de Goede <hdegoede@redhat.com>
62	
63	
64	Description
65	-----------
66	
67	Fintek F718xx/F8000 Super I/O chips include complete hardware monitoring
68	capabilities. They can monitor up to 9 voltages, 4 fans and 3 temperature
69	sensors.
70	
71	These chips also have fan controlling features, using either DC or PWM, in
72	three different modes (one manual, two automatic).
73	
74	The driver assumes that no more than one chip is present, which seems
75	reasonable.
76	
77	
78	Monitoring
79	----------
80	
81	The Voltage, Fan and Temperature Monitoring uses the standard sysfs
82	interface as documented in sysfs-interface, without any exceptions.
83	
84	
85	Fan Control
86	-----------
87	
88	Both PWM (pulse-width modulation) and DC fan speed control methods are
89	supported. The right one to use depends on external circuitry on the
90	motherboard, so the driver assumes that the BIOS set the method
91	properly.
92	
93	Note that the lowest numbered temperature zone trip point corresponds to
94	to the border between the highest and one but highest temperature zones, and
95	vica versa. So the temperature zone trip points 1-4 (or 1-2) go from high temp
96	to low temp! This is how things are implemented in the IC, and the driver
97	mimicks this.
98	
99	There are 2 modes to specify the speed of the fan, PWM duty cycle (or DC
100	voltage) mode, where 0-100% duty cycle (0-100% of 12V) is specified. And RPM
101	mode where the actual RPM of the fan (as measured) is controlled and the speed
102	gets specified as 0-100% of the fan#_full_speed file.
103	
104	Since both modes work in a 0-100% (mapped to 0-255) scale, there isn't a
105	whole lot of a difference when modifying fan control settings. The only
106	important difference is that in RPM mode the 0-100% controls the fan speed
107	between 0-100% of fan#_full_speed. It is assumed that if the BIOS programs
108	RPM mode, it will also set fan#_full_speed properly, if it does not then
109	fan control will not work properly, unless you set a sane fan#_full_speed
110	value yourself.
111	
112	Switching between these modes requires re-initializing a whole bunch of
113	registers, so the mode which the BIOS has set is kept. The mode is
114	printed when loading the driver.
115	
116	Three different fan control modes are supported; the mode number is written
117	to the pwm#_enable file. Note that not all modes are supported on all
118	chips, and some modes may only be available in RPM / PWM mode.
119	Writing an unsupported mode will result in an invalid parameter error.
120	
121	* 1: Manual mode
122	  You ask for a specific PWM duty cycle / DC voltage or a specific % of
123	  fan#_full_speed by writing to the pwm# file. This mode is only
124	  available on the F71858FG / F8000 if the fan channel is in RPM mode.
125	
126	* 2: Normal auto mode
127	  You can define a number of temperature/fan speed trip points, which % the
128	  fan should run at at this temp and which temp a fan should follow using the
129	  standard sysfs interface. The number and type of trip points is chip
130	  depended, see which files are available in sysfs.
131	  Fan/PWM channel 3 of the F8000 is always in this mode!
132	
133	* 3: Thermostat mode (Only available on the F8000 when in duty cycle mode)
134	  The fan speed is regulated to keep the temp the fan is mapped to between
135	  temp#_auto_point2_temp and temp#_auto_point3_temp.
136	
137	All of the automatic modes require that pwm1 corresponds to fan1, pwm2 to
138	fan2 and pwm3 to fan3.
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