Re: [RFT PATCH v2 01/12] drm/imx/dcss: Call drm_atomic_helper_shutdown() at shutdown time

[Laurentiu Palcu]

Hi,

On Thu, Sep 21, 2023 at 12:26:44PM -0700, Douglas Anderson wrote:
> Based on grepping through the source code this driver appears to be
> missing a call to drm_atomic_helper_shutdown() at system shutdown
> time. Among other things, this means that if a panel is in use that it
> won't be cleanly powered off at system shutdown time.
> 
> The fact that we should call drm_atomic_helper_shutdown() in the case
> of OS shutdown/restart comes straight out of the kernel doc "driver
> instance overview" in drm_drv.c.
> 
> Suggested-by: Maxime Ripard <mripard@xxxxxxxxxx>
> Reviewed-by: Maxime Ripard <mripard@xxxxxxxxxx>
> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>

No issues found on i.MX8MQ.

Tested-by: Laurentiu Palcu <laurentiu.palcu@xxxxxxxxxxx>
Reviewed-by: Laurentiu Palcu <laurentiu.palcu@xxxxxxxxxxx>

Thanks,
Laurentiu

> ---
> This commit is only compile-time tested.
> 
> (no changes since v1)
> 
>  drivers/gpu/drm/imx/dcss/dcss-drv.c | 8 ++++++++
>  drivers/gpu/drm/imx/dcss/dcss-kms.c | 7 +++++++
>  drivers/gpu/drm/imx/dcss/dcss-kms.h | 1 +
>  3 files changed, 16 insertions(+)
> 
> diff --git a/drivers/gpu/drm/imx/dcss/dcss-drv.c b/drivers/gpu/drm/imx/dcss/dcss-drv.c
> index c68b0d93ae9e..b61cec0cc79d 100644
> --- a/drivers/gpu/drm/imx/dcss/dcss-drv.c
> +++ b/drivers/gpu/drm/imx/dcss/dcss-drv.c
> @@ -92,6 +92,13 @@ static int dcss_drv_platform_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> +static void dcss_drv_platform_shutdown(struct platform_device *pdev)
> +{
> +	struct dcss_drv *mdrv = dev_get_drvdata(&pdev->dev);
> +
> +	dcss_kms_shutdown(mdrv->kms);
> +}
> +
>  static struct dcss_type_data dcss_types[] = {
>  	[DCSS_IMX8MQ] = {
>  		.name = "DCSS_IMX8MQ",
> @@ -114,6 +121,7 @@ MODULE_DEVICE_TABLE(of, dcss_of_match);
>  static struct platform_driver dcss_platform_driver = {
>  	.probe	= dcss_drv_platform_probe,
>  	.remove	= dcss_drv_platform_remove,
> +	.shutdown = dcss_drv_platform_shutdown,
>  	.driver	= {
>  		.name = "imx-dcss",
>  		.of_match_table	= dcss_of_match,
> diff --git a/drivers/gpu/drm/imx/dcss/dcss-kms.c b/drivers/gpu/drm/imx/dcss/dcss-kms.c
> index 896de946f8df..d0ea4e97cded 100644
> --- a/drivers/gpu/drm/imx/dcss/dcss-kms.c
> +++ b/drivers/gpu/drm/imx/dcss/dcss-kms.c
> @@ -172,3 +172,10 @@ void dcss_kms_detach(struct dcss_kms_dev *kms)
>  	dcss_crtc_deinit(&kms->crtc, drm);
>  	drm->dev_private = NULL;
>  }
> +
> +void dcss_kms_shutdown(struct dcss_kms_dev *kms)
> +{
> +	struct drm_device *drm = &kms->base;
> +
> +	drm_atomic_helper_shutdown(drm);
> +}
> diff --git a/drivers/gpu/drm/imx/dcss/dcss-kms.h b/drivers/gpu/drm/imx/dcss/dcss-kms.h
> index dfe5dd99eea3..62521c1fd6d2 100644
> --- a/drivers/gpu/drm/imx/dcss/dcss-kms.h
> +++ b/drivers/gpu/drm/imx/dcss/dcss-kms.h
> @@ -34,6 +34,7 @@ struct dcss_kms_dev {
>  
>  struct dcss_kms_dev *dcss_kms_attach(struct dcss_dev *dcss);
>  void dcss_kms_detach(struct dcss_kms_dev *kms);
> +void dcss_kms_shutdown(struct dcss_kms_dev *kms);
>  int dcss_crtc_init(struct dcss_crtc *crtc, struct drm_device *drm);
>  void dcss_crtc_deinit(struct dcss_crtc *crtc, struct drm_device *drm);
>  struct dcss_plane *dcss_plane_init(struct drm_device *drm,
> -- 
> 2.42.0.515.g380fc7ccd1-goog
>