R.Marek@sh.cvut.cz | 7f15b66 | 2005-05-26 12:42:19 +0000 | [diff] [blame] | 1 | Kernel driver it87 |
| 2 | ================== |
| 3 | |
| 4 | Supported chips: |
| 5 | * IT8705F |
| 6 | Prefix: 'it87' |
Jean Delvare | 9174999 | 2005-10-08 00:10:00 +0200 | [diff] [blame^] | 7 | Addresses scanned: from Super I/O config space (8 I/O ports) |
R.Marek@sh.cvut.cz | 7f15b66 | 2005-05-26 12:42:19 +0000 | [diff] [blame] | 8 | Datasheet: Publicly available at the ITE website |
| 9 | http://www.ite.com.tw/ |
| 10 | * IT8712F |
| 11 | Prefix: 'it8712' |
| 12 | Addresses scanned: I2C 0x28 - 0x2f |
Jean Delvare | 9174999 | 2005-10-08 00:10:00 +0200 | [diff] [blame^] | 13 | from Super I/O config space (8 I/O ports) |
R.Marek@sh.cvut.cz | 7f15b66 | 2005-05-26 12:42:19 +0000 | [diff] [blame] | 14 | Datasheet: Publicly available at the ITE website |
| 15 | http://www.ite.com.tw/ |
| 16 | * SiS950 [clone of IT8705F] |
Jean Delvare | 9174999 | 2005-10-08 00:10:00 +0200 | [diff] [blame^] | 17 | Prefix: 'it87' |
| 18 | Addresses scanned: from Super I/O config space (8 I/O ports) |
R.Marek@sh.cvut.cz | 7f15b66 | 2005-05-26 12:42:19 +0000 | [diff] [blame] | 19 | Datasheet: No longer be available |
| 20 | |
| 21 | Author: Christophe Gauthron <chrisg@0-in.com> |
| 22 | |
| 23 | |
| 24 | Module Parameters |
| 25 | ----------------- |
| 26 | |
| 27 | * update_vbat: int |
| 28 | |
| 29 | 0 if vbat should report power on value, 1 if vbat should be updated after |
| 30 | each read. Default is 0. On some boards the battery voltage is provided |
| 31 | by either the battery or the onboard power supply. Only the first reading |
| 32 | at power on will be the actual battery voltage (which the chip does |
| 33 | automatically). On other boards the battery voltage is always fed to |
| 34 | the chip so can be read at any time. Excessive reading may decrease |
| 35 | battery life but no information is given in the datasheet. |
| 36 | |
| 37 | * fix_pwm_polarity int |
| 38 | |
| 39 | Force PWM polarity to active high (DANGEROUS). Some chips are |
| 40 | misconfigured by BIOS - PWM values would be inverted. This option tries |
| 41 | to fix this. Please contact your BIOS manufacturer and ask him for fix. |
| 42 | |
| 43 | Description |
| 44 | ----------- |
| 45 | |
| 46 | This driver implements support for the IT8705F, IT8712F and SiS950 chips. |
| 47 | |
| 48 | This driver also supports IT8712F, which adds SMBus access, and a VID |
| 49 | input, used to report the Vcore voltage of the Pentium processor. |
| 50 | The IT8712F additionally features VID inputs. |
| 51 | |
| 52 | These chips are 'Super I/O chips', supporting floppy disks, infrared ports, |
| 53 | joysticks and other miscellaneous stuff. For hardware monitoring, they |
| 54 | include an 'environment controller' with 3 temperature sensors, 3 fan |
| 55 | rotation speed sensors, 8 voltage sensors, and associated alarms. |
| 56 | |
| 57 | Temperatures are measured in degrees Celsius. An alarm is triggered once |
| 58 | when the Overtemperature Shutdown limit is crossed. |
| 59 | |
| 60 | Fan rotation speeds are reported in RPM (rotations per minute). An alarm is |
| 61 | triggered if the rotation speed has dropped below a programmable limit. Fan |
| 62 | readings can be divided by a programmable divider (1, 2, 4 or 8) to give the |
| 63 | readings more range or accuracy. Not all RPM values can accurately be |
| 64 | represented, so some rounding is done. With a divider of 2, the lowest |
| 65 | representable value is around 2600 RPM. |
| 66 | |
| 67 | Voltage sensors (also known as IN sensors) report their values in volts. An |
| 68 | alarm is triggered if the voltage has crossed a programmable minimum or |
| 69 | maximum limit. Note that minimum in this case always means 'closest to |
| 70 | zero'; this is important for negative voltage measurements. All voltage |
| 71 | inputs can measure voltages between 0 and 4.08 volts, with a resolution of |
| 72 | 0.016 volt. The battery voltage in8 does not have limit registers. |
| 73 | |
| 74 | The VID lines (IT8712F only) encode the core voltage value: the voltage |
| 75 | level your processor should work with. This is hardcoded by the mainboard |
| 76 | and/or processor itself. It is a value in volts. |
| 77 | |
| 78 | If an alarm triggers, it will remain triggered until the hardware register |
| 79 | is read at least once. This means that the cause for the alarm may already |
| 80 | have disappeared! Note that in the current implementation, all hardware |
| 81 | registers are read whenever any data is read (unless it is less than 1.5 |
| 82 | seconds since the last update). This means that you can easily miss |
| 83 | once-only alarms. |
| 84 | |
| 85 | The IT87xx only updates its values each 1.5 seconds; reading it more often |
| 86 | will do no harm, but will return 'old' values. |
| 87 | |
| 88 | To change sensor N to a thermistor, 'echo 2 > tempN_type' where N is 1, 2, |
| 89 | or 3. To change sensor N to a thermal diode, 'echo 3 > tempN_type'. |
| 90 | Give 0 for unused sensor. Any other value is invalid. To configure this at |
| 91 | startup, consult lm_sensors's /etc/sensors.conf. (2 = thermistor; |
| 92 | 3 = thermal diode) |
| 93 | |
| 94 | The fan speed control features are limited to manual PWM mode. Automatic |
| 95 | "Smart Guardian" mode control handling is not implemented. However |
| 96 | if you want to go for "manual mode" just write 1 to pwmN_enable. |