Kernel driver sg2042-mcu¶

Supported chips:

Onboard MCU for sg2042

Addresses scanned: -

Prefix: ‘sg2042-mcu’

Authors:

Inochi Amaoto <inochiama@outlook.com>

Description¶

This driver supprts hardware monitoring for onboard MCU with i2c interface.

This driver does not auto-detect devices. You will have to instantiate the devices explicitly. Please see How to instantiate I2C devices for details.

The following table shows the standard entries support by the driver:

Name	Description
temp1_input	Measured temperature of SoC
temp1_crit	Critical high temperature
temp1_crit_hyst	hysteresis temperature restore from Critical
temp2_input	Measured temperature of the base board

The following table shows the extra entries support by the driver (the MCU device is in i2c subsystem):

Name	Perm	Description
reset_count	RO	Reset count of the SoC
uptime	RO	Seconds after the MCU is powered
reset_reason	RO	Reset reason for the last reset
repower_policy	RW	Execution policy when triggering repower

repower_policy: The repower is triggered when the temperature of the SoC falls below the hysteresis temperature after triggering a shutdown due to reaching the critical temperature. The valid values for this entry are “repower” and “keep”. “keep” will leave the SoC down when the triggering repower, and “repower” will boot the SoC.

If debugfs is available, this driver exposes some hardware specific data in /sys/kernel/debug/sg2042-mcu/*/.

Name	Format	Description
firmware_version	0x%02x	firmware version of the MCU
pcb_version	0x%02x	version number of the base board
board_type	0x%02x	identifiers for the base board
mcu_type	%d	type of the MCU: 0 is STM32, 1 is GD32