Kernel driver max31785 ====================== Supported chips: * Maxim MAX31785, MAX31785A Prefix: 'max31785' or 'max31785a' Addresses scanned: - Datasheet: https://datasheets.maximintegrated.com/en/ds/MAX31785.pdf Author: Andrew Jeffery Description ----------- The Maxim MAX31785 is a PMBus device providing closed-loop, multi-channel fan management with temperature and remote voltage sensing. Various fan control features are provided, including PWM frequency control, temperature hysteresis, dual tachometer measurements, and fan health monitoring. For dual-rotor configurations the MAX31785A exposes the second rotor tachometer readings in attributes fan[5-8]_input. By contrast the MAX31785 only exposes the slowest rotor measurement, and does so in the fan[1-4]_input attributes. Usage Notes ----------- This driver does not probe for PMBus devices. You will have to instantiate devices explicitly. Sysfs attributes ---------------- ======================= ======================================================= fan[1-4]_alarm Fan alarm. fan[1-4]_fault Fan fault. fan[1-8]_input Fan RPM. On the MAX31785A, inputs 5-8 correspond to the second rotor of fans 1-4 fan[1-4]_target Fan input target in[1-6]_crit Critical maximum output voltage in[1-6]_crit_alarm Output voltage critical high alarm in[1-6]_input Measured output voltage in[1-6]_label "vout[18-23]" in[1-6]_lcrit Critical minimum output voltage in[1-6]_lcrit_alarm Output voltage critical low alarm in[1-6]_max Maximum output voltage in[1-6]_max_alarm Output voltage high alarm in[1-6]_min Minimum output voltage in[1-6]_min_alarm Output voltage low alarm pwm[1-4] Fan target duty cycle (0..255) pwm[1-4]_enable 0: Full-speed 1: Manual PWM control 2: Automatic PWM (tach-feedback RPM fan-control) 3: Automatic closed-loop (temp-feedback fan-control) temp[1-11]_crit Critical high temperature temp[1-11]_crit_alarm Chip temperature critical high alarm temp[1-11]_input Measured temperature temp[1-11]_max Maximum temperature temp[1-11]_max_alarm Chip temperature high alarm ======================= =======================================================