Re: [PATCH v5 3/5] phy: fsl-imx8mq-usb: add runtime PM support

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] Missing `pm_runtime_disable()` in `imx8mq_usb_phy_probe()` error paths causes a `disable_depth` imbalance and PM state corruption.
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commit e9418c8d510e8492ef9a52ace4cb6d672041d448
Author: Xu Yang <xu.yang_2@nxp.com>

phy: fsl-imx8mq-usb: add runtime PM support

This commit adds runtime PM support to ensure the PHY is properly powered
and clocked during register access, preventing potential system hangs.

> diff --git a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> --- a/drivers/phy/freescale/phy-fsl-imx8mq-usb.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8mq-usb.c

[ ... ]

> @@ -708,6 +695,9 @@ static int imx8mq_usb_phy_probe(struct platform_device *pdev)
>  	if (IS_ERR(imx_phy->base))
>  		return PTR_ERR(imx_phy->base);
>  
> +	pm_runtime_set_active(dev);
> +	pm_runtime_enable(dev);
> +
>  	phy_ops = of_device_get_match_data(dev);
>  	if (!phy_ops)
>  		return -EINVAL;

[Severity: High]
Does this code need a cleanup path to call pm_runtime_disable() on probe
failures?

If functions following pm_runtime_enable() fail (such as
of_device_get_match_data(), devm_phy_create(), or devm_regulator_get()),
the driver returns the error directly without cleaning up the PM state.

This can leave the disable_depth counter out of sync. If the device probe
defers (for example, if devm_regulator_get() returns -EPROBE_DEFER) and
runs again, the subsequent pm_runtime_enable() could drop the counter
below zero. This might trigger an unbalanced pm_runtime_enable warning
and leave the device permanently stuck in RPM_ACTIVE.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260630-imx8mp-usb-phy-improvement-v5-0-25d616403844@nxp.com?part=3

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