Re: [PATCH 58/78] media: exynos-gsc: use pm_runtime_resume_and_get()

[Sylwester Nawrocki]

On 24.04.2021 08:45, Mauro Carvalho Chehab wrote:
> Commit dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
> added pm_runtime_resume_and_get() in order to automatically handle
> dev->power.usage_count decrement on errors.
> 
> Use the new API, in order to cleanup the error check logic.
> 
> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
> ---
>  drivers/media/platform/exynos-gsc/gsc-core.c | 3 +--
>  drivers/media/platform/exynos-gsc/gsc-m2m.c  | 2 +-
>  2 files changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/media/platform/exynos-gsc/gsc-core.c b/drivers/media/platform/exynos-gsc/gsc-core.c
> index 9f41c2e7097a..9d5841194f6b 100644
> --- a/drivers/media/platform/exynos-gsc/gsc-core.c
> +++ b/drivers/media/platform/exynos-gsc/gsc-core.c
> @@ -1210,7 +1210,7 @@ static int gsc_remove(struct platform_device *pdev)
>  	struct gsc_dev *gsc = platform_get_drvdata(pdev);
>  	int i;
>  
> -	pm_runtime_get_sync(&pdev->dev);
> +	pm_runtime_resume_and_get(&pdev->dev);
>  
>  	gsc_unregister_m2m_device(gsc);
>  	v4l2_device_unregister(&gsc->v4l2_dev);
> @@ -1219,7 +1219,6 @@ static int gsc_remove(struct platform_device *pdev)
>  	for (i = 0; i < gsc->num_clocks; i++)
>  		clk_disable_unprepare(gsc->clock[i]);
>  
> -	pm_runtime_put_noidle(&pdev->dev);

If we do this then the device usage count will not get decremented
after the pm_runtime_resume_and_get() call above and after driver
unload/load cycle it will not be possible to suspend the device.
I wouldn't be changing anything in gsc_remove(), pm_runtime_get_sync()
works better in that case.

Regards,
Sylwester

>  	pm_runtime_disable(&pdev->dev);
>  
>  	dev_dbg(&pdev->dev, "%s driver unloaded\n", pdev->name