| Kernel driver f71882fg |
| ====================== |
| |
| Supported chips: |
| * Fintek F71858FG |
| Prefix: 'f71858fg' |
| Addresses scanned: none, address read from Super I/O config space |
| Datasheet: Available from the Fintek website |
| * Fintek F71862FG and F71863FG |
| Prefix: 'f71862fg' |
| Addresses scanned: none, address read from Super I/O config space |
| Datasheet: Available from the Fintek website |
| * Fintek F71882FG and F71883FG |
| Prefix: 'f71882fg' |
| Addresses scanned: none, address read from Super I/O config space |
| Datasheet: Available from the Fintek website |
| * Fintek F8000 |
| Prefix: 'f8000' |
| Addresses scanned: none, address read from Super I/O config space |
| Datasheet: Not public |
| |
| Author: Hans de Goede <hdegoede@redhat.com> |
| |
| |
| Description |
| ----------- |
| |
| Fintek F718xxFG/F8000 Super I/O chips include complete hardware monitoring |
| capabilities. They can monitor up to 9 voltages (3 for the F8000), 4 fans and |
| 3 temperature sensors. |
| |
| These chips also have fan controlling features, using either DC or PWM, in |
| three different modes (one manual, two automatic). |
| |
| The driver assumes that no more than one chip is present, which seems |
| reasonable. |
| |
| |
| Monitoring |
| ---------- |
| |
| The Voltage, Fan and Temperature Monitoring uses the standard sysfs |
| interface as documented in sysfs-interface, without any exceptions. |
| |
| |
| Fan Control |
| ----------- |
| |
| Both PWM (pulse-width modulation) and DC fan speed control methods are |
| supported. The right one to use depends on external circuitry on the |
| motherboard, so the driver assumes that the BIOS set the method |
| properly. |
| |
| There are 2 modes to specify the speed of the fan, PWM duty cycle (or DC |
| voltage) mode, where 0-100% duty cycle (0-100% of 12V) is specified. And RPM |
| mode where the actual RPM of the fan (as measured) is controlled and the speed |
| gets specified as 0-100% of the fan#_full_speed file. |
| |
| Since both modes work in a 0-100% (mapped to 0-255) scale, there isn't a |
| whole lot of a difference when modifying fan control settings. The only |
| important difference is that in RPM mode the 0-100% controls the fan speed |
| between 0-100% of fan#_full_speed. It is assumed that if the BIOS programs |
| RPM mode, it will also set fan#_full_speed properly, if it does not then |
| fan control will not work properly, unless you set a sane fan#_full_speed |
| value yourself. |
| |
| Switching between these modes requires re-initializing a whole bunch of |
| registers, so the mode which the BIOS has set is kept. The mode is |
| printed when loading the driver. |
| |
| Three different fan control modes are supported; the mode number is written |
| to the pwm#_enable file. Note that not all modes are supported on all |
| chips, and some modes may only be available in RPM / PWM mode. |
| Writing an unsupported mode will result in an invalid parameter error. |
| |
| * 1: Manual mode |
| You ask for a specific PWM duty cycle / DC voltage or a specific % of |
| fan#_full_speed by writing to the pwm# file. This mode is only |
| available on the F71858FG / F8000 if the fan channel is in RPM mode. |
| |
| * 2: Normal auto mode |
| You can define a number of temperature/fan speed trip points, which % the |
| fan should run at at this temp and which temp a fan should follow using the |
| standard sysfs interface. The number and type of trip points is chip |
| depended, see which files are available in sysfs. |
| Fan/PWM channel 3 of the F8000 is always in this mode! |
| |
| * 3: Thermostat mode (Only available on the F8000 when in duty cycle mode) |
| The fan speed is regulated to keep the temp the fan is mapped to between |
| temp#_auto_point2_temp and temp#_auto_point3_temp. |
| |
| Both of the automatic modes require that pwm1 corresponds to fan1, pwm2 to |
| fan2 and pwm3 to fan3. |