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