Re: [PATCH v7 07/12] gpio: mxc: use __free guard for runtime PM cleanup

[Frank Li <Frank.li@oss.nxp.com>]

On Tue, Oct 27, 2026 at 08:09:34PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@nxp.com>
>
> Use a scope-based cleanup guard to disable runtime PM and drop the
> probe-scoped pm_runtime_get_noresume() reference on error paths.  Disarm
> it with retain_and_null_ptr() before the success-path
> pm_runtime_put_autosuspend().
>
> The guard keeps the required order: pm_runtime_disable() runs before
> pm_runtime_put_noidle(), so dropping the reference cannot trigger a
> runtime suspend callback while probe is still unwinding.
>
> Signed-off-by: Peng Fan <peng.fan@nxp.com>
> ---

Reviewed-by: Frank Li <Frank.Li@nxp.com>

>  drivers/gpio/gpio-mxc.c | 21 +++++++++++++++++++--
>  1 file changed, 19 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c
> index 21c74b244c1f..68857730b5e3 100644
> --- a/drivers/gpio/gpio-mxc.c
> +++ b/drivers/gpio/gpio-mxc.c
> @@ -28,6 +28,20 @@
>  #include <linux/of.h>
>  #include <linux/bug.h>
>
> +static void mxc_gpio_pm_release(struct device *dev)
> +{
> +	if (!dev)
> +		return;
> +
> +	if (pm_runtime_enabled(dev))
> +		pm_runtime_disable(dev);
> +
> +	pm_runtime_put_noidle(dev);
> +}
> +
> +DEFINE_FREE(mxc_gpio_pm_cleanup, struct device *,
> +	    mxc_gpio_pm_release(_T))
> +
>  #define IMX_SCU_WAKEUP_OFF		0
>  #define IMX_SCU_WAKEUP_LOW_LVL		4
>  #define IMX_SCU_WAKEUP_FALL_EDGE	5
> @@ -487,6 +501,9 @@ static int mxc_gpio_probe(struct platform_device *pdev)
>  		return PTR_ERR(port->clk);
>
>  	pm_runtime_get_noresume(dev);
> +
> +	struct device *pm_guard __free(mxc_gpio_pm_cleanup) = dev;
> +
>  	pm_runtime_set_active(dev);
>  	pm_runtime_enable(dev);
>
> @@ -562,6 +579,8 @@ static int mxc_gpio_probe(struct platform_device *pdev)
>  	mxc_update_irq_chained_handler(port, true);
>
>  	platform_set_drvdata(pdev, port);
> +
> +	retain_and_null_ptr(pm_guard);
>  	pm_runtime_put_autosuspend(dev);
>
>  	return 0;
> @@ -569,8 +588,6 @@ static int mxc_gpio_probe(struct platform_device *pdev)
>  out_irqdomain_remove:
>  	irq_domain_remove(port->domain);
>  out_bgio:
> -	pm_runtime_disable(dev);
> -	pm_runtime_put_noidle(dev);
>  	dev_info(dev, "%s failed with errno %d\n", __func__, err);
>  	return err;
>  }
>
> --
> 2.51.0
>
>