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Il Han195a4b42015-08-30 20:44:26 +09001Kernel driver max31790
2======================
3
4Supported chips:
5 * Maxim MAX31790
6 Prefix: 'max31790'
7 Addresses scanned: -
8 Datasheet: http://pdfserv.maximintegrated.com/en/ds/MAX31790.pdf
9
10Author: Il Han <corone.il.han@gmail.com>
11
12
13Description
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15
16This driver implements support for the Maxim MAX31790 chip.
17
18The MAX31790 controls the speeds of up to six fans using six independent
19PWM outputs. The desired fan speeds (or PWM duty cycles) are written
20through the I2C interface. The outputs drive "4-wire" fans directly,
21or can be used to modulate the fan's power terminals using an external
22pass transistor.
23
24Tachometer inputs monitor fan tachometer logic outputs for precise (+/-1%)
25monitoring and control of fan RPM as well as detection of fan failure.
26Six pins are dedicated tachometer inputs. Any of the six PWM outputs can
27also be configured to serve as tachometer inputs.
28
29
30Sysfs entries
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32
33fan[1-12]_input RO fan tachometer speed in RPM
34fan[1-12]_fault RO fan experienced fault
35fan[1-6]_target RW desired fan speed in RPM
36pwm[1-6]_enable RW regulator mode, 0=disabled, 1=manual mode, 2=rpm mode
37pwm[1-6] RW fan target duty cycle (0-255)