| xj | b04a402 | 2021-11-25 15:01:52 +0800 | [diff] [blame] | 1 | Kernel driver max31785 |
| 2 | ====================== |
| 3 | |
| 4 | Supported chips: |
| 5 | * Maxim MAX31785, MAX31785A |
| 6 | Prefix: 'max31785' or 'max31785a' |
| 7 | Addresses scanned: - |
| 8 | Datasheet: https://datasheets.maximintegrated.com/en/ds/MAX31785.pdf |
| 9 | |
| 10 | Author: Andrew Jeffery <andrew@aj.id.au> |
| 11 | |
| 12 | Description |
| 13 | ----------- |
| 14 | |
| 15 | The Maxim MAX31785 is a PMBus device providing closed-loop, multi-channel fan |
| 16 | management with temperature and remote voltage sensing. Various fan control |
| 17 | features are provided, including PWM frequency control, temperature hysteresis, |
| 18 | dual tachometer measurements, and fan health monitoring. |
| 19 | |
| 20 | For dual-rotor configurations the MAX31785A exposes the second rotor tachometer |
| 21 | readings in attributes fan[5-8]_input. By contrast the MAX31785 only exposes |
| 22 | the slowest rotor measurement, and does so in the fan[1-4]_input attributes. |
| 23 | |
| 24 | Usage Notes |
| 25 | ----------- |
| 26 | |
| 27 | This driver does not probe for PMBus devices. You will have to instantiate |
| 28 | devices explicitly. |
| 29 | |
| 30 | Sysfs attributes |
| 31 | ---------------- |
| 32 | |
| 33 | fan[1-4]_alarm Fan alarm. |
| 34 | fan[1-4]_fault Fan fault. |
| 35 | fan[1-8]_input Fan RPM. On the MAX31785A, inputs 5-8 correspond to the |
| 36 | second rotor of fans 1-4 |
| 37 | fan[1-4]_target Fan input target |
| 38 | |
| 39 | in[1-6]_crit Critical maximum output voltage |
| 40 | in[1-6]_crit_alarm Output voltage critical high alarm |
| 41 | in[1-6]_input Measured output voltage |
| 42 | in[1-6]_label "vout[18-23]" |
| 43 | in[1-6]_lcrit Critical minimum output voltage |
| 44 | in[1-6]_lcrit_alarm Output voltage critical low alarm |
| 45 | in[1-6]_max Maximum output voltage |
| 46 | in[1-6]_max_alarm Output voltage high alarm |
| 47 | in[1-6]_min Minimum output voltage |
| 48 | in[1-6]_min_alarm Output voltage low alarm |
| 49 | |
| 50 | pwm[1-4] Fan target duty cycle (0..255) |
| 51 | pwm[1-4]_enable 0: Full-speed |
| 52 | 1: Manual PWM control |
| 53 | 2: Automatic PWM (tach-feedback RPM fan-control) |
| 54 | 3: Automatic closed-loop (temp-feedback fan-control) |
| 55 | |
| 56 | temp[1-11]_crit Critical high temperature |
| 57 | temp[1-11]_crit_alarm Chip temperature critical high alarm |
| 58 | temp[1-11]_input Measured temperature |
| 59 | temp[1-11]_max Maximum temperature |
| 60 | temp[1-11]_max_alarm Chip temperature high alarm |