[PATCH resend v3] reset: renesas: Fix Runtime PM usage

[PATCH resend v3] reset: renesas: Fix Runtime PM usage

[Heiner Kallweit]

If pm_runtime_resume_and_get() fails then it returns w/o the RPM usage
counter being incremented. In this case call pm_runtime_put() in
remove() will result in a usage counter imbalance. Therefore check the
return code of pm_runtime_resume_and_get() and bail out in case of error.

Fixes: bee08559701f ("reset: renesas: Add RZ/G2L usbphy control driver")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
v2:
- bail out in case of error instead of switching to pm_runtime_get_sync()
v3:
- add dev_err_probe() in case of error
---
 drivers/reset/reset-rzg2l-usbphy-ctrl.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/reset/reset-rzg2l-usbphy-ctrl.c b/drivers/reset/reset-rzg2l-usbphy-ctrl.c
index e0704fd2b..46fcd2218 100644
--- a/drivers/reset/reset-rzg2l-usbphy-ctrl.c
+++ b/drivers/reset/reset-rzg2l-usbphy-ctrl.c
@@ -137,7 +137,12 @@ static int rzg2l_usbphy_ctrl_probe(struct platform_device *pdev)
 	dev_set_drvdata(dev, priv);
 
 	pm_runtime_enable(&pdev->dev);
-	pm_runtime_resume_and_get(&pdev->dev);
+	error = pm_runtime_resume_and_get(&pdev->dev);
+	if (error < 0) {
+		pm_runtime_disable(&pdev->dev);
+		reset_control_assert(priv->rstc);
+		return dev_err_probe(&pdev->dev, error, "pm_runtime_resume_and_get failed");
+	}
 
 	/* put pll and phy into reset state */
 	spin_lock_irqsave(&priv->lock, flags);
-- 
2.34.1

RE: [PATCH resend v3] reset: renesas: Fix Runtime PM usage

[Biju Das]

Hi Heiner,

Thanks for the patch.

> Subject: [PATCH resend v3] reset: renesas: Fix Runtime PM usage
> 
> If pm_runtime_resume_and_get() fails then it returns w/o the RPM usage
> counter being incremented. In this case call pm_runtime_put() in
> remove() will result in a usage counter imbalance. Therefore check the
> return code of pm_runtime_resume_and_get() and bail out in case of error.
> 
> Fixes: bee08559701f ("reset: renesas: Add RZ/G2L usbphy control driver")
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>

Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>

Cheers,
Biju

> ---
> v2:
> - bail out in case of error instead of switching to pm_runtime_get_sync()
> v3:
> - add dev_err_probe() in case of error
> ---
>  drivers/reset/reset-rzg2l-usbphy-ctrl.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/reset/reset-rzg2l-usbphy-ctrl.c
> b/drivers/reset/reset-rzg2l-usbphy-ctrl.c
> index e0704fd2b..46fcd2218 100644
> --- a/drivers/reset/reset-rzg2l-usbphy-ctrl.c
> +++ b/drivers/reset/reset-rzg2l-usbphy-ctrl.c
> @@ -137,7 +137,12 @@ static int rzg2l_usbphy_ctrl_probe(struct
> platform_device *pdev)
>  	dev_set_drvdata(dev, priv);
> 
>  	pm_runtime_enable(&pdev->dev);
> -	pm_runtime_resume_and_get(&pdev->dev);
> +	error = pm_runtime_resume_and_get(&pdev->dev);
> +	if (error < 0) {
> +		pm_runtime_disable(&pdev->dev);
> +		reset_control_assert(priv->rstc);
> +		return dev_err_probe(&pdev->dev, error,
> "pm_runtime_resume_and_get failed");
> +	}
> 
>  	/* put pll and phy into reset state */
>  	spin_lock_irqsave(&priv->lock, flags);
> --
> 2.34.1

Re: [PATCH resend v3] reset: renesas: Fix Runtime PM usage

[Philipp Zabel]

On Wed, 2021-12-15 at 10:18 +0000, Biju Das wrote:
> Hi Heiner,
> 
> Thanks for the patch.
> 
> > Subject: [PATCH resend v3] reset: renesas: Fix Runtime PM usage
> > 
> > If pm_runtime_resume_and_get() fails then it returns w/o the RPM usage
> > counter being incremented. In this case call pm_runtime_put() in
> > remove() will result in a usage counter imbalance. Therefore check the
> > return code of pm_runtime_resume_and_get() and bail out in case of error.
> > 
> > Fixes: bee08559701f ("reset: renesas: Add RZ/G2L usbphy control driver")
> > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> 
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>

Thank you both, applied to reset/fixes.

regards
Philipp