Re: [PATCH] regulator: pf1550: fix which regulator is notified

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] The interrupt handler unconditionally returns IRQ_HANDLED even when it completely fails to recognize the interrupt, defeating spurious interrupt detection.
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commit 756013e824bd37aa338c50b32f4e6024e5f64dfc
Author: Donggeun Yoo <donggeunyoo.kernel@gmail.com>

    regulator: pf1550: fix which regulator is notified

This commit fixes the regulator notification logic in the pf1550 driver.
It replaces string-based matching of regulator names with ID-based lookups
to reliably notify the correct consumer when a fault occurs.

> diff --git a/drivers/regulator/pf1550-regulator.c b/drivers/regulator/pf1550-regulator.c
> index 610eac9bb9cb2..ceee553a84b23 100644
> --- a/drivers/regulator/pf1550-regulator.c
> +++ b/drivers/regulator/pf1550-regulator.c
[ ... ]
> @@ -283,63 +283,61 @@ static struct pf1550_desc pf1550_regulators[] = {
[ ... ]
>  static irqreturn_t pf1550_regulator_irq_handler(int irq, void *data)
>  {
> +	const struct pf1550_regulator_irq *map;
>  	struct pf1550_regulator_info *info = data;
>  	struct device *dev = info->dev;
>  	struct platform_device *pdev = to_platform_device(dev);
>  	int i, irq_type = -1;
> -	unsigned int event;
>  
>  	for (i = 0; i < PF1550_REGULATOR_IRQ_NR; i++)
>  		if (irq == platform_get_irq(pdev, i))
>  			irq_type = i;
>  
[ ... ]
> +	if (irq_type < 0 || irq_type >= (int)ARRAY_SIZE(pf1550_regulator_irqs)) {
> +		dev_err(dev, "regulator interrupt: irq %d occurred\n", irq_type);
> +		return IRQ_HANDLED;
                ^^^^^^^^^^^^^^^^^^^
[Severity: High]
This is a pre-existing issue, but returning IRQ_HANDLED when the driver
completely fails to recognize the interrupt defeats the kernel's spurious
interrupt detection.

If pf1550_regulator_irq_handler() is invoked with an IRQ that does not match
any index in the loop, irq_type remains -1 and this branch is taken. Since
IRQ_HANDLED is returned, the spurious interrupt detection is falsely told
the interrupt was handled successfully and will not mask the virtual IRQ line.

If the PMIC continuously asserts an unhandled fault, could the parent
regmap-irq thread loop endlessly resulting in an interrupt storm and CPU
lockup? Should this return IRQ_NONE instead?

>  	}
>  
> +	map = &pf1550_regulator_irqs[irq_type];
> +
> +	for (i = 0; i < PF1550_MAX_REGULATOR; i++)
> +		if (rdev_get_id(info->rdevs[i]) == map->id)
> +			regulator_notifier_call_chain(info->rdevs[i],
> +						      map->event, NULL);
> +
>  	return IRQ_HANDLED;
>  }

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260904105624.48577-1-donggeunyoo.kernel@gmail.com?part=1