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