| 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: from Super I/O config space (8 I/O ports) |
| Datasheet: Publicly available at the ITE website |
| http://www.ite.com.tw/ |
| * IT8716F/IT8726F |
| Prefix: 'it8716' |
| Addresses scanned: from Super I/O config space (8 I/O ports) |
| Datasheet: Publicly available at the ITE website |
| http://www.ite.com.tw/product_info/file/pc/IT8716F_V0.3.ZIP |
| http://www.ite.com.tw/product_info/file/pc/IT8726F_V0.3.pdf |
| * IT8718F |
| Prefix: 'it8718' |
| Addresses scanned: from Super I/O config space (8 I/O ports) |
| Datasheet: Publicly available at the ITE website |
| http://www.ite.com.tw/product_info/file/pc/IT8718F_V0.2.zip |
| http://www.ite.com.tw/product_info/file/pc/IT8718F_V0%203_(for%20C%20version).zip |
| * SiS950 [clone of IT8705F] |
| Prefix: 'it87' |
| Addresses scanned: from Super I/O config space (8 I/O ports) |
| Datasheet: No longer be available |
| |
| Authors: |
| Christophe Gauthron <chrisg@0-in.com> |
| Jean Delvare <khali@linux-fr.org> |
| |
| |
| 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. |
| |
| |
| Hardware Interfaces |
| ------------------- |
| |
| All the chips suported by this driver are LPC Super-I/O chips, accessed |
| through the LPC bus (ISA-like I/O ports). The IT8712F additionally has an |
| SMBus interface to the hardware monitoring functions. This driver no |
| longer supports this interface though, as it is slower and less reliable |
| than the ISA access, and was only available on a small number of |
| motherboard models. |
| |
| |
| Description |
| ----------- |
| |
| This driver implements support for the IT8705F, IT8712F, IT8716F, |
| IT8718F, IT8726F and SiS950 chips. |
| |
| 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. |
| |
| The IT8712F and IT8716F additionally feature VID inputs, used to report |
| the Vcore voltage of the processor. The early IT8712F have 5 VID pins, |
| the IT8716F and late IT8712F have 6. They are shared with other functions |
| though, so the functionality may not be available on a given system. |
| The driver dumbly assume it is there. |
| |
| The IT8718F also features VID inputs (up to 8 pins) but the value is |
| stored in the Super-I/O configuration space. Due to technical limitations, |
| this value can currently only be read once at initialization time, so |
| the driver won't notice and report changes in the VID value. The two |
| upper VID bits share their pins with voltage inputs (in5 and in6) so you |
| can't have both on a given board. |
| |
| The IT8716F, IT8718F and later IT8712F revisions have support for |
| 2 additional fans. They are supported by the driver for the IT8716F and |
| IT8718F but not for the IT8712F |
| |
| The IT8716F and IT8718F, and late IT8712F and IT8705F also have optional |
| 16-bit tachometer counters for fans 1 to 3. This is better (no more fan |
| clock divider mess) but not compatible with the older chips and |
| revisions. For now, the driver only uses the 16-bit mode on the |
| IT8716F and IT8718F. |
| |
| The IT8726F is just bit enhanced IT8716F with additional hardware |
| for AMD power sequencing. Therefore the chip will appear as IT8716F |
| to userspace applications. |
| |
| 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. When |
| 16-bit tachometer counters aren't used, fan readings can be divided by |
| a programmable divider (1, 2, 4 or 8) to give the readings more range or |
| accuracy. With a divider of 2, the lowest representable value is around |
| 2600 RPM. Not all RPM values can accurately be represented, so some rounding |
| is done. |
| |
| 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/IT8716F/IT8718F) 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) |
| |
| |
| Fan speed control |
| ----------------- |
| |
| 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. |
| |
| If you are only able to control the fan speed with very small PWM values, |
| try lowering the PWM base frequency (pwm1_freq). Depending on the fan, |
| it may give you a somewhat greater control range. The same frequency is |
| used to drive all fan outputs, which is why pwm2_freq and pwm3_freq are |
| read-only. |
