Re: [PATCH v1 3/3] mfd: max8907: Convert to use device managed poweroff handler

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] mfd: max8907 sys-off handler returns raw error code halting notifier chain
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commit 42fddb54f9db77c2dde889b0a3e0f261fd20ec9b
Author: Svyatoslav Ryhel <clamor95@gmail.com>

mfd: max8907: Convert to use device managed poweroff handler

This commit replaces the legacy global pm_power_off function pointer
assignment with the devm_register_sys_off_handler() helper.

> diff --git a/drivers/mfd/max8907.c b/drivers/mfd/max8907.c
> index 363ac80c0593b..0cecb53b62078 100644
> --- a/drivers/mfd/max8907.c
> +++ b/drivers/mfd/max8907.c
[ ... ]
> @@ -173,19 +174,18 @@ static const struct regmap_irq_chip max8907_rtc_irq_chip = {
>  	.num_irqs = ARRAY_SIZE(max8907_rtc_irqs),
>  };
>  
> -static struct max8907 *max8907_pm_off;
> -static void max8907_power_off(void)
> +static int max8907_power_off(struct sys_off_data *data)
>  {
> -	regmap_update_bits(max8907_pm_off->regmap_gen, MAX8907_REG_RESET_CNFG,
> -			MAX8907_MASK_POWER_OFF, MAX8907_MASK_POWER_OFF);
> +	struct max8907 *max8907 = data->cb_data;
> +
> +	return regmap_update_bits(max8907->regmap_gen, MAX8907_REG_RESET_CNFG,
> +				  MAX8907_MASK_POWER_OFF, MAX8907_MASK_POWER_OFF);
>  }

[Severity: Medium]
Does this inadvertently halt the sys-off notifier chain if the regmap operation
fails?

If regmap_update_bits() in max8907_power_off() encounters an error, such as an
I2C transaction failure, it returns a negative error code like -EIO. Because
notifier chains evaluate return values using the NOTIFY_STOP_MASK (0x8000) bit,
a negative integer will have this bit set. This would immediately abort the
sys-off notifier call chain instead of propagating a proper NOTIFY_* constant.

When this fails, it might prevent lower-priority fallback power-off methods,
like ACPI, PSCI, or EFI shutdown, from being attempted, potentially hanging
the system instead of safely powering off.

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Sashiko AI review · https://sashiko.dev/#/patchset/20260927155745.187758-1-clamor95@gmail.com?part=3