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Part 3: Move the drivers documentation, plus two general documentation files. Note that the patch "adds trailing whitespace", because it does move the files as-is, and some files happen to have trailing whitespace. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
97 lines
4.2 KiB
Plaintext
97 lines
4.2 KiB
Plaintext
Kernel driver it87
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==================
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Supported chips:
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* IT8705F
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Prefix: 'it87'
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Addresses scanned: from Super I/O config space, or default ISA 0x290 (8 I/O ports)
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Datasheet: Publicly available at the ITE website
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http://www.ite.com.tw/
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* IT8712F
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Prefix: 'it8712'
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Addresses scanned: I2C 0x28 - 0x2f
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from Super I/O config space, or default ISA 0x290 (8 I/O ports)
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Datasheet: Publicly available at the ITE website
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http://www.ite.com.tw/
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* SiS950 [clone of IT8705F]
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Prefix: 'sis950'
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Addresses scanned: from Super I/O config space, or default ISA 0x290 (8 I/O ports)
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Datasheet: No longer be available
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Author: Christophe Gauthron <chrisg@0-in.com>
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Module Parameters
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-----------------
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* update_vbat: int
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0 if vbat should report power on value, 1 if vbat should be updated after
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each read. Default is 0. On some boards the battery voltage is provided
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by either the battery or the onboard power supply. Only the first reading
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at power on will be the actual battery voltage (which the chip does
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automatically). On other boards the battery voltage is always fed to
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the chip so can be read at any time. Excessive reading may decrease
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battery life but no information is given in the datasheet.
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* fix_pwm_polarity int
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Force PWM polarity to active high (DANGEROUS). Some chips are
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misconfigured by BIOS - PWM values would be inverted. This option tries
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to fix this. Please contact your BIOS manufacturer and ask him for fix.
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Description
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-----------
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This driver implements support for the IT8705F, IT8712F and SiS950 chips.
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This driver also supports IT8712F, which adds SMBus access, and a VID
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input, used to report the Vcore voltage of the Pentium processor.
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The IT8712F additionally features VID inputs.
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These chips are 'Super I/O chips', supporting floppy disks, infrared ports,
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joysticks and other miscellaneous stuff. For hardware monitoring, they
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include an 'environment controller' with 3 temperature sensors, 3 fan
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rotation speed sensors, 8 voltage sensors, and associated alarms.
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Temperatures are measured in degrees Celsius. An alarm is triggered once
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when the Overtemperature Shutdown limit is crossed.
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Fan rotation speeds are reported in RPM (rotations per minute). An alarm is
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triggered if the rotation speed has dropped below a programmable limit. Fan
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readings can be divided by a programmable divider (1, 2, 4 or 8) to give the
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readings more range or accuracy. Not all RPM values can accurately be
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represented, so some rounding is done. With a divider of 2, the lowest
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representable value is around 2600 RPM.
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Voltage sensors (also known as IN sensors) report their values in volts. An
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alarm is triggered if the voltage has crossed a programmable minimum or
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maximum limit. Note that minimum in this case always means 'closest to
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zero'; this is important for negative voltage measurements. All voltage
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inputs can measure voltages between 0 and 4.08 volts, with a resolution of
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0.016 volt. The battery voltage in8 does not have limit registers.
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The VID lines (IT8712F only) encode the core voltage value: the voltage
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level your processor should work with. This is hardcoded by the mainboard
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and/or processor itself. It is a value in volts.
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If an alarm triggers, it will remain triggered until the hardware register
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is read at least once. This means that the cause for the alarm may already
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have disappeared! Note that in the current implementation, all hardware
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registers are read whenever any data is read (unless it is less than 1.5
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seconds since the last update). This means that you can easily miss
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once-only alarms.
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The IT87xx only updates its values each 1.5 seconds; reading it more often
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will do no harm, but will return 'old' values.
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To change sensor N to a thermistor, 'echo 2 > tempN_type' where N is 1, 2,
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or 3. To change sensor N to a thermal diode, 'echo 3 > tempN_type'.
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Give 0 for unused sensor. Any other value is invalid. To configure this at
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startup, consult lm_sensors's /etc/sensors.conf. (2 = thermistor;
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3 = thermal diode)
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The fan speed control features are limited to manual PWM mode. Automatic
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"Smart Guardian" mode control handling is not implemented. However
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if you want to go for "manual mode" just write 1 to pwmN_enable.
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