[PATCH v3 1/5] dt-bindings: mfd: rk806: allow to customize PMIC reset mode

Krzysztof Kozlowski krzk at kernel.org
Thu Jun 19 02:54:15 PDT 2025


On Wed, Jun 18, 2025 at 12:32:40PM GMT, Quentin Schulz wrote:
> From: Quentin Schulz <quentin.schulz at cherry.de>
> 
> The RK806 PMIC allows to configure its reset/restart behavior whenever
> the PMIC is reset either programmatically or via some external pins
> (e.g. PWRCTRL or RESETB).
> 
> The following modes exist:
>  - 0; restart PMU,
>  - 1; reset all power off reset registers and force state to switch to
>    ACTIVE mode,
>  - 2; same as mode 1 and also pull RESETB pin down for 5ms,
> 
> For example, some hardware may require a full restart (mode 0) in order
> to function properly as regulators are shortly interrupted in this mode.
> 
> This is the case for RK3588 Jaguar and RK3588 Tiger which have a
> companion microcontroller running on an independent power supply and
> monitoring the PMIC power rail to know the state of the main system.
> When it detects a restart, it resets its own IPs exposed to the main
> system as if to simulate its own reset. Failing to perform this fake
> reset of the microcontroller may break things (e.g. watchdog not
> automatically disabled, buzzer still running until manually disabled,
> leftover configuration from previous main system state, etc...).

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski at linaro.org>

Best regards,
Krzysztof




More information about the linux-arm-kernel mailing list