| Kernel driver it87 | |
| ================== | |
| Supported chips: | |
| * IT8705F | |
| Prefix: 'it87' | |
| Addresses scanned: from Super I/O config space (8 I/O ports) | |
| Datasheet: Publicly available at the ITE website | |
| http://www.ite.com.tw/ | |
| * IT8712F | |
| Prefix: 'it8712' | |
| Addresses scanned: I2C 0x2d | |
| from Super I/O config space (8 I/O ports) | |
| Datasheet: Publicly available at the ITE website | |
| http://www.ite.com.tw/ | |
| * SiS950 [clone of IT8705F] | |
| Prefix: 'it87' | |
| Addresses scanned: from Super I/O config space (8 I/O ports) | |
| Datasheet: No longer be available | |
| Author: Christophe Gauthron <chrisg@0-in.com> | |
| Module Parameters | |
| ----------------- | |
| * update_vbat: int | |
| 0 if vbat should report power on value, 1 if vbat should be updated after | |
| each read. Default is 0. On some boards the battery voltage is provided | |
| by either the battery or the onboard power supply. Only the first reading | |
| at power on will be the actual battery voltage (which the chip does | |
| automatically). On other boards the battery voltage is always fed to | |
| the chip so can be read at any time. Excessive reading may decrease | |
| battery life but no information is given in the datasheet. | |
| * fix_pwm_polarity int | |
| Force PWM polarity to active high (DANGEROUS). Some chips are | |
| misconfigured by BIOS - PWM values would be inverted. This option tries | |
| to fix this. Please contact your BIOS manufacturer and ask him for fix. | |
| Description | |
| ----------- | |
| This driver implements support for the IT8705F, IT8712F and SiS950 chips. | |
| This driver also supports IT8712F, which adds SMBus access, and a VID | |
| input, used to report the Vcore voltage of the Pentium processor. | |
| The IT8712F additionally features VID inputs. | |
| These chips are 'Super I/O chips', supporting floppy disks, infrared ports, | |
| joysticks and other miscellaneous stuff. For hardware monitoring, they | |
| include an 'environment controller' with 3 temperature sensors, 3 fan | |
| rotation speed sensors, 8 voltage sensors, and associated alarms. | |
| Temperatures are measured in degrees Celsius. An alarm is triggered once | |
| when the Overtemperature Shutdown limit is crossed. | |
| Fan rotation speeds are reported in RPM (rotations per minute). An alarm is | |
| triggered if the rotation speed has dropped below a programmable limit. Fan | |
| readings can be divided by a programmable divider (1, 2, 4 or 8) to give the | |
| readings more range or accuracy. Not all RPM values can accurately be | |
| represented, so some rounding is done. With a divider of 2, the lowest | |
| representable value is around 2600 RPM. | |
| Voltage sensors (also known as IN sensors) report their values in volts. An | |
| alarm is triggered if the voltage has crossed a programmable minimum or | |
| maximum limit. Note that minimum in this case always means 'closest to | |
| zero'; this is important for negative voltage measurements. All voltage | |
| inputs can measure voltages between 0 and 4.08 volts, with a resolution of | |
| 0.016 volt. The battery voltage in8 does not have limit registers. | |
| The VID lines (IT8712F only) encode the core voltage value: the voltage | |
| level your processor should work with. This is hardcoded by the mainboard | |
| and/or processor itself. It is a value in volts. | |
| If an alarm triggers, it will remain triggered until the hardware register | |
| is read at least once. This means that the cause for the alarm may already | |
| have disappeared! Note that in the current implementation, all hardware | |
| registers are read whenever any data is read (unless it is less than 1.5 | |
| seconds since the last update). This means that you can easily miss | |
| once-only alarms. | |
| The IT87xx only updates its values each 1.5 seconds; reading it more often | |
| will do no harm, but will return 'old' values. | |
| To change sensor N to a thermistor, 'echo 2 > tempN_type' where N is 1, 2, | |
| or 3. To change sensor N to a thermal diode, 'echo 3 > tempN_type'. | |
| Give 0 for unused sensor. Any other value is invalid. To configure this at | |
| startup, consult lm_sensors's /etc/sensors.conf. (2 = thermistor; | |
| 3 = thermal diode) | |
| The fan speed control features are limited to manual PWM mode. Automatic | |
| "Smart Guardian" mode control handling is not implemented. However | |
| if you want to go for "manual mode" just write 1 to pwmN_enable. |