|  | Kernel driver f71805f | 
|  | ===================== | 
|  |  | 
|  | Supported chips: | 
|  | * Fintek F71805F/FG | 
|  | Prefix: 'f71805f' | 
|  | Addresses scanned: none, address read from Super I/O config space | 
|  | Datasheet: Available from the Fintek website | 
|  | * Fintek F71806F/FG | 
|  | Prefix: 'f71872f' | 
|  | Addresses scanned: none, address read from Super I/O config space | 
|  | Datasheet: Available from the Fintek website | 
|  | * Fintek F71872F/FG | 
|  | Prefix: 'f71872f' | 
|  | Addresses scanned: none, address read from Super I/O config space | 
|  | Datasheet: Available from the Fintek website | 
|  |  | 
|  | Author: Jean Delvare <khali@linux-fr.org> | 
|  |  | 
|  | Thanks to Denis Kieft from Barracuda Networks for the donation of a | 
|  | test system (custom Jetway K8M8MS motherboard, with CPU and RAM) and | 
|  | for providing initial documentation. | 
|  |  | 
|  | Thanks to Kris Chen and Aaron Huang from Fintek for answering technical | 
|  | questions and providing additional documentation. | 
|  |  | 
|  | Thanks to Chris Lin from Jetway for providing wiring schematics and | 
|  | answering technical questions. | 
|  |  | 
|  |  | 
|  | Description | 
|  | ----------- | 
|  |  | 
|  | The Fintek F71805F/FG Super I/O chip includes complete hardware monitoring | 
|  | capabilities. It can monitor up to 9 voltages (counting its own power | 
|  | source), 3 fans and 3 temperature sensors. | 
|  |  | 
|  | This chip also has fan controlling features, using either DC or PWM, in | 
|  | three different modes (one manual, two automatic). | 
|  |  | 
|  | The Fintek F71872F/FG Super I/O chip is almost the same, with two | 
|  | additional internal voltages monitored (VSB and battery). It also features | 
|  | 6 VID inputs. The VID inputs are not yet supported by this driver. | 
|  |  | 
|  | The Fintek F71806F/FG Super-I/O chip is essentially the same as the | 
|  | F71872F/FG, and is undistinguishable therefrom. | 
|  |  | 
|  | The driver assumes that no more than one chip is present, which seems | 
|  | reasonable. | 
|  |  | 
|  |  | 
|  | Voltage Monitoring | 
|  | ------------------ | 
|  |  | 
|  | Voltages are sampled by an 8-bit ADC with a LSB of 8 mV. The supported | 
|  | range is thus from 0 to 2.040 V. Voltage values outside of this range | 
|  | need external resistors. An exception is in0, which is used to monitor | 
|  | the chip's own power source (+3.3V), and is divided internally by a | 
|  | factor 2. For the F71872F/FG, in9 (VSB) and in10 (battery) are also | 
|  | divided internally by a factor 2. | 
|  |  | 
|  | The two LSB of the voltage limit registers are not used (always 0), so | 
|  | you can only set the limits in steps of 32 mV (before scaling). | 
|  |  | 
|  | The wirings and resistor values suggested by Fintek are as follow: | 
|  |  | 
|  | pin                                           expected | 
|  | name    use           R1      R2     divider  raw val. | 
|  |  | 
|  | in0     VCC     VCC3.3V     int.    int.        2.00    1.65 V | 
|  | in1     VIN1    VTT1.2V      10K       -        1.00    1.20 V | 
|  | in2     VIN2    VRAM        100K    100K        2.00   ~1.25 V (1) | 
|  | in3     VIN3    VCHIPSET     47K    100K        1.47    2.24 V (2) | 
|  | in4     VIN4    VCC5V       200K     47K        5.25    0.95 V | 
|  | in5     VIN5    +12V        200K     20K       11.00    1.05 V | 
|  | in6     VIN6    VCC1.5V      10K       -        1.00    1.50 V | 
|  | in7     VIN7    VCORE        10K       -        1.00   ~1.40 V (1) | 
|  | in8     VIN8    VSB5V       200K     47K        1.00    0.95 V | 
|  | in10    VSB     VSB3.3V     int.    int.        2.00    1.65 V (3) | 
|  | in9     VBAT    VBATTERY    int.    int.        2.00    1.50 V (3) | 
|  |  | 
|  | (1) Depends on your hardware setup. | 
|  | (2) Obviously not correct, swapping R1 and R2 would make more sense. | 
|  | (3) F71872F/FG only. | 
|  |  | 
|  | These values can be used as hints at best, as motherboard manufacturers | 
|  | are free to use a completely different setup. As a matter of fact, the | 
|  | Jetway K8M8MS uses a significantly different setup. You will have to | 
|  | find out documentation about your own motherboard, and edit sensors.conf | 
|  | accordingly. | 
|  |  | 
|  | Each voltage measured has associated low and high limits, each of which | 
|  | triggers an alarm when crossed. | 
|  |  | 
|  |  | 
|  | Fan Monitoring | 
|  | -------------- | 
|  |  | 
|  | Fan rotation speeds are reported as 12-bit values from a gated clock | 
|  | signal. Speeds down to 366 RPM can be measured. There is no theoretical | 
|  | high limit, but values over 6000 RPM seem to cause problem. The effective | 
|  | resolution is much lower than you would expect, the step between different | 
|  | register values being 10 rather than 1. | 
|  |  | 
|  | The chip assumes 2 pulse-per-revolution fans. | 
|  |  | 
|  | An alarm is triggered if the rotation speed drops below a programmable | 
|  | limit or is too low to be measured. | 
|  |  | 
|  |  | 
|  | Temperature Monitoring | 
|  | ---------------------- | 
|  |  | 
|  | Temperatures are reported in degrees Celsius. Each temperature measured | 
|  | has a high limit, those crossing triggers an alarm. There is an associated | 
|  | hysteresis value, below which the temperature has to drop before the | 
|  | alarm is cleared. | 
|  |  | 
|  | All temperature channels are external, there is no embedded temperature | 
|  | sensor. Each channel can be used for connecting either a thermal diode | 
|  | or a thermistor. The driver reports the currently selected mode, but | 
|  | doesn't allow changing it. In theory, the BIOS should have configured | 
|  | everything properly. | 
|  |  | 
|  |  | 
|  | 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. The driver will report the method, but won't let you change | 
|  | it. | 
|  |  | 
|  | When the PWM method is used, you can select the operating frequency, | 
|  | from 187.5 kHz (default) to 31 Hz. The best frequency depends on the | 
|  | fan model. As a rule of thumb, lower frequencies seem to give better | 
|  | control, but may generate annoying high-pitch noise. So a frequency just | 
|  | above the audible range, such as 25 kHz, may be a good choice; if this | 
|  | doesn't give you good linear control, try reducing it. Fintek recommends | 
|  | not going below 1 kHz, as the fan tachometers get confused by lower | 
|  | frequencies as well. | 
|  |  | 
|  | When the DC method is used, Fintek recommends not going below 5 V, which | 
|  | corresponds to a pwm value of 106 for the driver. The driver doesn't | 
|  | enforce this limit though. | 
|  |  | 
|  | Three different fan control modes are supported; the mode number is written | 
|  | to the pwm<n>_enable file. | 
|  |  | 
|  | * 1: Manual mode | 
|  | You ask for a specific PWM duty cycle or DC voltage by writing to the | 
|  | pwm<n> file. | 
|  |  | 
|  | * 2: Temperature mode | 
|  | You define 3 temperature/fan speed trip points using the | 
|  | pwm<n>_auto_point<m>_temp and _fan files. These define a staircase | 
|  | relationship between temperature and fan speed with two additional points | 
|  | interpolated between the values that you define. When the temperature | 
|  | is below auto_point1_temp the fan is switched off. | 
|  |  | 
|  | * 3: Fan speed mode | 
|  | You ask for a specific fan speed by writing to the fan<n>_target file. | 
|  |  | 
|  | Both of the automatic modes require that pwm1 corresponds to fan1, pwm2 to | 
|  | fan2 and pwm3 to fan3. Temperature mode also requires that temp1 corresponds | 
|  | to pwm1 and fan1, etc. |