Re: [PATCH RESEND v9 07/18] media: platform: Improve the implementation of the system PM ops

[Tomasz Figa]

Hi Xia,

On Thu, Jun 04, 2020 at 05:05:42PM +0800, Xia Jiang wrote:
> Add v4l2_m2m_suspend() function call in mtk_jpeg_suspend() to make sure
> that the current frame is processed completely before suspend.
> Add v4l2_m2m_resume() function call in mtk_jpeg_resume() to unblock the
> driver from scheduling next frame.
> 
> Signed-off-by: Xia Jiang <xia.ji...@mediatek.com>
> ---
> v9: use v4l2_m2m_suspend() and v4l2_m2m_resume() to improve the
>     implemention of the system PM ops
> ---
>  drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 

Thank you for the patch. Please see my comments inline.

> diff --git a/drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c 
> b/drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c
> index 7f74597262fc..49bdbf1c435f 100644
> --- a/drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c
> +++ b/drivers/media/platform/mtk-jpeg/mtk_jpeg_core.c
> @@ -1208,10 +1208,13 @@ static __maybe_unused int mtk_jpeg_pm_resume(struct 
> device *dev)
>  static __maybe_unused int mtk_jpeg_suspend(struct device *dev)
>  {
>       int ret;
> +     struct mtk_jpeg_dev *jpeg = dev_get_drvdata(dev);
>  
>       if (pm_runtime_suspended(dev))
>               return 0;
>  
> +     v4l2_m2m_suspend(jpeg->m2m_dev);
> +
>       ret = mtk_jpeg_pm_suspend(dev);
>       return ret;
>  }

This could be simplified into:

{
        struct mtk_jpeg_dev *jpeg = dev_get_drvdata(dev);

        v4l2_m2m_suspend(jpeg->m2m_dev);
        return pm_runtime_force_suspend(dev);
}

> @@ -1219,12 +1222,15 @@ static __maybe_unused int mtk_jpeg_suspend(struct 
> device *dev)
>  static __maybe_unused int mtk_jpeg_resume(struct device *dev)
>  {
>       int ret;
> +     struct mtk_jpeg_dev *jpeg = dev_get_drvdata(dev);
>  
>       if (pm_runtime_suspended(dev))
>               return 0;
>  
>       ret = mtk_jpeg_pm_resume(dev);
>  
> +     v4l2_m2m_resume(jpeg->m2m_dev);
> +
>       return ret;
>  }

Similarly here:

{
        struct mtk_jpeg_dev *jpeg = dev_get_drvdata(dev);
        int ret;

        ret = pm_runtime_force_resume(dev);
        if (ret < 0)
                return ret;

        v4l2_m2m_resume(jpeg->m2m_dev);
}

The pm_runtime_force_*() helpers will make sure that the right runtime PM
state is restored.

Best regards,
Tomasz