Kernel driver max8688

Supported chips:

Author: Guenter Roeck <>


This driver supports hardware monitoring for Maxim MAX8688 Digital Power-Supply Controller/Monitor with PMBus Interface.

The driver is a client driver to the core PMBus driver. Please see Documentation/hwmon/pmbus.rst for details on PMBus client drivers.

Usage Notes

This driver does not auto-detect devices. You will have to instantiate the devices explicitly. Please see Documentation/i2c/instantiating-devices.rst for details.

Platform data support

The driver supports standard PMBus driver platform data.

Sysfs entries

The following attributes are supported. Limits are read-write; all other attributes are read-only.

in1_label “vout1”
in1_input Measured voltage. From READ_VOUT register.
in1_min Minimum Voltage. From VOUT_UV_WARN_LIMIT register.
in1_max Maximum voltage. From VOUT_OV_WARN_LIMIT register.
in1_lcrit Critical minimum Voltage. VOUT_UV_FAULT_LIMIT register.
in1_crit Critical maximum voltage. From VOUT_OV_FAULT_LIMIT register.
in1_min_alarm Voltage low alarm. From VOLTAGE_UV_WARNING status.
in1_max_alarm Voltage high alarm. From VOLTAGE_OV_WARNING status.
in1_lcrit_alarm Voltage critical low alarm. From VOLTAGE_UV_FAULT status.
in1_crit_alarm Voltage critical high alarm. From VOLTAGE_OV_FAULT status.
in1_highest Historical maximum voltage.
in1_reset_history Write any value to reset history.
curr1_label “iout1”
curr1_input Measured current. From READ_IOUT register.
curr1_max Maximum current. From IOUT_OC_WARN_LIMIT register.
curr1_crit Critical maximum current. From IOUT_OC_FAULT_LIMIT register.
curr1_max_alarm Current high alarm. From IOUT_OC_WARN_LIMIT register.
curr1_crit_alarm Current critical high alarm. From IOUT_OC_FAULT status.
curr1_highest Historical maximum current.
curr1_reset_history Write any value to reset history.
temp1_input Measured temperature. From READ_TEMPERATURE_1 register.
temp1_max Maximum temperature. From OT_WARN_LIMIT register.
temp1_crit Critical high temperature. From OT_FAULT_LIMIT register.
temp1_max_alarm Chip temperature high alarm. Set by comparing READ_TEMPERATURE_1 with OT_WARN_LIMIT if TEMP_OT_WARNING status is set.
temp1_crit_alarm Chip temperature critical high alarm. Set by comparing READ_TEMPERATURE_1 with OT_FAULT_LIMIT if TEMP_OT_FAULT status is set.
temp1_highest Historical maximum temperature.
temp1_reset_history Write any value to reset history.