Re: [PATCH v14 2/6] reboot: hw_protection_trigger: use standardized numeric shutdown/reboot reasons instead of strings

[Faruque Ansari]

Hi Daniel Lezcano,

On 02-Oct-26 1:17 PM, Daniel Lezcano wrote:
> On Mon, Sep 21, 2026 at 11:14:17PM +0530, Faruque Ansari wrote:
>
> [ ... ]
>
> > +/**
> > + * enum psc_reason - Enumerates reasons for power state changes.
> > + *
> > + * This enum defines various reasons why a system might transition into a
> > + * shutdown, reboot, or kexec state. While originally intended for hardware
> > + * protection events, `psc_reason` can be extended to track other system
> > + * transitions, such as controlled reboots triggered by software or
> > + * maintenance operations.
> > + *
> > + * The values in this enumeration provide structured and standardized
> > + * identifiers that replace free-form string descriptions. They are designed
> > + * to be stored efficiently, making them suitable for use in environments
> > + * with limited storage, such as battery-backed RTC registers, non-volatile
> > + * memory, or bootloader communication mechanisms.
> > + *
> > + * Importantly, the order of these values **must remain stable**, as
> > + * bootloaders, user-space tools, or post-mortem investigation utilities
> > + * may rely on their numerical representation for consistent behavior.
> > + *
> > + * @PSCR_UNKNOWN: Unknown or unspecified reason for the power state change.
> > + *	This value serves as a default when no explicit cause is recorded.
> > + *
> > + * @PSCR_UNDER_VOLTAGE: Shutdown or reboot triggered due to supply voltage
> > + *      dropping below a safe threshold. This helps prevent instability or
> > + *      corruption caused by insufficient power.
> > + *
> > + * @PSCR_OVER_CURRENT: System shutdown or reboot due to excessive current draw,
> > + *      which may indicate a short circuit, an overloaded power rail, or other
> > + *      hardware faults requiring immediate action.
> > + *
> > + * @PSCR_REGULATOR_FAILURE: A critical failure in a voltage regulator, causing
> > + *      improper power delivery. This may be due to internal component failure,
> > + *      transient conditions, or external load issues requiring mitigation.
> > + *
> > + * @PSCR_OVER_TEMPERATURE: System shutdown or reboot due to excessive thermal
> > + *	conditions. This attempts to prevent hardware damage when temperature
> > + *	sensors detect unsafe levels, often impacting CPUs, GPUs, or power
> > + *	components.
> > + *
> > + * @PSCR_EC_PANIC: Shutdown or reboot triggered by an Embedded Controller (EC)
> > + *	panic. The EC is a microcontroller responsible for low-level system
> > + *	management, including power sequencing, thermal control, and battery
> > + *	management. An EC panic may indicate critical firmware issues, power
> > + *	management errors, or an unrecoverable hardware fault requiring
> > + *	immediate response.
> > + *
> > + * @PSCR_REASON_COUNT: Number of defined power state change reasons. This
> > + *	value is useful for range checking and potential future extensions
> > + *	while maintaining compatibility.
> > + */
> > +enum psc_reason {
> > +	PSCR_UNKNOWN,
> > +	PSCR_UNDER_VOLTAGE,
> > +	PSCR_OVER_CURRENT,
> > +	PSCR_REGULATOR_FAILURE,
> > +	PSCR_OVER_TEMPERATURE,
> > +	PSCR_EC_PANIC,
> > +
> > +	/* Number of reasons */
> > +	PSCR_REASON_COUNT,
> > +};
> > +
> > +#define PSCR_MAX_REASON	(PSCR_REASON_COUNT - 1)
>
> May be I missed it but where is PSCR_MAX_REASON used in this series?

Ack. Agree, PSCR_MAX_REASON is not used anywhere in this series. 
It appears to be a leftover from an earlier revision. I'll remove 
it in the next version. Thanks for catching that.

> [ ... ]
>
> > +/**
> > + * psc_reason_to_str - Converts a power state change reason enum to a string.
> > + * @reason: The `psc_reason` enum value to be converted.
> > + *
> > + * This function provides a human-readable string representation of the power
> > + * state change reason, making it easier to interpret logs and debug messages.
> > + *
> > + * Return:
> > + * - A string corresponding to the given `psc_reason` value.
> > + * - `"Invalid"` if the value is not recognized.
> > + */
> > +const char *psc_reason_to_str(enum psc_reason reason)
> > +{
> > +	if (reason < 0 || reason >= PSCR_REASON_COUNT)
> > +		return "Invalid";
>
> s/Invalid/Invalid reason/
>
> [ ... ]

Ack. I'll fix it in the next revision.

Thanks,
Faruque Ansari

> With that fixed you can add:
>
> Reviewed-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxxxxxxxx>