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1 | Kernel driver it87 | ||
2 | ================== | ||
3 | |||
4 | Supported chips: | ||
5 | * IT8705F | ||
6 | Prefix: 'it87' | ||
7 | Addresses scanned: from Super I/O config space, or default ISA 0x290 (8 I/O ports) | ||
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 | ||
13 | from Super I/O config space, or default ISA 0x290 (8 I/O ports) | ||
14 | Datasheet: Publicly available at the ITE website | ||
15 | http://www.ite.com.tw/ | ||
16 | * SiS950 [clone of IT8705F] | ||
17 | Prefix: 'sis950' | ||
18 | Addresses scanned: from Super I/O config space, or default ISA 0x290 (8 I/O ports) | ||
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. | ||