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Il Han195a4b42015-08-30 20:44:26 +09001Kernel driver max31790
2======================
3
4Supported chips:
Mauro Carvalho Chehabb04f2f72019-04-17 06:46:28 -03005
Il Han195a4b42015-08-30 20:44:26 +09006 * Maxim MAX31790
Mauro Carvalho Chehabb04f2f72019-04-17 06:46:28 -03007
Il Han195a4b42015-08-30 20:44:26 +09008 Prefix: 'max31790'
Mauro Carvalho Chehabb04f2f72019-04-17 06:46:28 -03009
Il Han195a4b42015-08-30 20:44:26 +090010 Addresses scanned: -
Mauro Carvalho Chehabb04f2f72019-04-17 06:46:28 -030011
Alexander A. Klimovad736c12020-07-19 19:55:12 +020012 Datasheet: https://pdfserv.maximintegrated.com/en/ds/MAX31790.pdf
Il Han195a4b42015-08-30 20:44:26 +090013
14Author: Il Han <corone.il.han@gmail.com>
15
16
17Description
18-----------
19
20This driver implements support for the Maxim MAX31790 chip.
21
22The MAX31790 controls the speeds of up to six fans using six independent
23PWM outputs. The desired fan speeds (or PWM duty cycles) are written
24through the I2C interface. The outputs drive "4-wire" fans directly,
25or can be used to modulate the fan's power terminals using an external
26pass transistor.
27
28Tachometer inputs monitor fan tachometer logic outputs for precise (+/-1%)
29monitoring and control of fan RPM as well as detection of fan failure.
30Six pins are dedicated tachometer inputs. Any of the six PWM outputs can
31also be configured to serve as tachometer inputs.
32
33
34Sysfs entries
35-------------
36
Mauro Carvalho Chehabb04f2f72019-04-17 06:46:28 -030037================== === =======================================================
Il Han195a4b42015-08-30 20:44:26 +090038fan[1-12]_input RO fan tachometer speed in RPM
39fan[1-12]_fault RO fan experienced fault
40fan[1-6]_target RW desired fan speed in RPM
41pwm[1-6]_enable RW regulator mode, 0=disabled, 1=manual mode, 2=rpm mode
42pwm[1-6] RW fan target duty cycle (0-255)
Mauro Carvalho Chehabb04f2f72019-04-17 06:46:28 -030043================== === =======================================================