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