0001 Kernel driver max31790
0002 ======================
0003
0004 Supported chips:
0005
0006 * Maxim MAX31790
0007
0008 Prefix: 'max31790'
0009
0010 Addresses scanned: -
0011
0012 Datasheet: https://pdfserv.maximintegrated.com/en/ds/MAX31790.pdf
0013
0014 Author: Il Han <corone.il.han@gmail.com>
0015
0016
0017 Description
0018 -----------
0019
0020 This driver implements support for the Maxim MAX31790 chip.
0021
0022 The MAX31790 controls the speeds of up to six fans using six independent
0023 PWM outputs. The desired fan speeds (or PWM duty cycles) are written
0024 through the I2C interface. The outputs drive "4-wire" fans directly,
0025 or can be used to modulate the fan's power terminals using an external
0026 pass transistor.
0027
0028 Tachometer inputs monitor fan tachometer logic outputs for precise (+/-1%)
0029 monitoring and control of fan RPM as well as detection of fan failure.
0030 Six pins are dedicated tachometer inputs. Any of the six PWM outputs can
0031 also be configured to serve as tachometer inputs.
0032
0033
0034 Sysfs entries
0035 -------------
0036
0037 ================== === =======================================================
0038 fan[1-12]_input RO fan tachometer speed in RPM
0039 fan[1-12]_fault RO fan experienced fault
0040 fan[1-6]_target RW desired fan speed in RPM
0041 pwm[1-6]_enable RW regulator mode, 0=disabled (duty cycle=0%), 1=manual mode, 2=rpm mode
0042 pwm[1-6] RW read: current pwm duty cycle,
0043 write: target pwm duty cycle (0-255)
0044 ================== === =======================================================
