| 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@redhat.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. |