Re: [PATCH v3] drm/msm: use compatible lists to find mdp node

From: Dmitry Baryshkov
Date: Tue Nov 09 2021 - 08:23:56 EST


On Tue, 9 Nov 2021 at 12:47, Krishna Manikandan
<quic_mkrishn@xxxxxxxxxxx> wrote:
>
> In the current implementation, substring comparison
> using device node name is used to find mdp node
> during driver probe. Use compatible string list instead
> of node name to get mdp node from the parent mdss node.
>
> Signed-off-by: Krishna Manikandan <quic_mkrishn@xxxxxxxxxxx>
>
> Changes in v2:
> - Use compatible lists instead of duplicate string
> check (Stephen Boyd)
>
> Changes in v3:
> - Use match tables to find the mdp node (Stephen Boyd)
> ---
> drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 3 ++-
> drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c | 3 ++-
> drivers/gpu/drm/msm/msm_drv.c | 7 ++++---
> drivers/gpu/drm/msm/msm_kms.h | 3 +++
> 4 files changed, 11 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> index ad247c0..c778b6d 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> @@ -1273,7 +1273,7 @@ static const struct dev_pm_ops dpu_pm_ops = {
> pm_runtime_force_resume)
> };
>
> -static const struct of_device_id dpu_dt_match[] = {
> +const struct of_device_id dpu_dt_match[] = {
> { .compatible = "qcom,sdm845-dpu", },
> { .compatible = "qcom,sc7180-dpu", },
> { .compatible = "qcom,sc7280-dpu", },
> @@ -1282,6 +1282,7 @@ static const struct of_device_id dpu_dt_match[] = {
> {}
> };
> MODULE_DEVICE_TABLE(of, dpu_dt_match);
> +EXPORT_SYMBOL(dpu_dt_match);

There is no need to export these symbols, as they will be used within
the module.

>
> static struct platform_driver dpu_driver = {
> .probe = dpu_dev_probe,
> diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
> index 7b24224..8b97008 100644
> --- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
> +++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c
> @@ -1031,13 +1031,14 @@ static const struct dev_pm_ops mdp5_pm_ops = {
> SET_RUNTIME_PM_OPS(mdp5_runtime_suspend, mdp5_runtime_resume, NULL)
> };
>
> -static const struct of_device_id mdp5_dt_match[] = {
> +const struct of_device_id mdp5_dt_match[] = {
> { .compatible = "qcom,mdp5", },
> /* to support downstream DT files */
> { .compatible = "qcom,mdss_mdp", },
> {}
> };
> MODULE_DEVICE_TABLE(of, mdp5_dt_match);
> +EXPORT_SYMBOL(mdp5_dt_match);
>
> static struct platform_driver mdp5_driver = {
> .probe = mdp5_dev_probe,
> diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
> index 7936e8d..445788f 100644
> --- a/drivers/gpu/drm/msm/msm_drv.c
> +++ b/drivers/gpu/drm/msm/msm_drv.c
> @@ -1277,9 +1277,10 @@ static int add_components_mdp(struct device *mdp_dev,
> return 0;
> }
>
> -static int compare_name_mdp(struct device *dev, void *data)
> +static int find_mdp_node(struct device *dev, void *data)
> {
> - return (strstr(dev_name(dev), "mdp") != NULL);
> + return of_match_node(dpu_dt_match, dev->of_node) ||
> + of_match_node(mdp5_dt_match, dev->of_node);
> }
>
> static int add_display_components(struct platform_device *pdev,
> @@ -1304,7 +1305,7 @@ static int add_display_components(struct platform_device *pdev,
> return ret;
> }
>
> - mdp_dev = device_find_child(dev, NULL, compare_name_mdp);
> + mdp_dev = device_find_child(dev, NULL, find_mdp_node);
> if (!mdp_dev) {
> DRM_DEV_ERROR(dev, "failed to find MDSS MDP node\n");
> of_platform_depopulate(dev);
> diff --git a/drivers/gpu/drm/msm/msm_kms.h b/drivers/gpu/drm/msm/msm_kms.h
> index 6a42b81..8b132c8 100644
> --- a/drivers/gpu/drm/msm/msm_kms.h
> +++ b/drivers/gpu/drm/msm/msm_kms.h
> @@ -198,6 +198,9 @@ struct msm_kms *mdp4_kms_init(struct drm_device *dev);
> struct msm_kms *mdp5_kms_init(struct drm_device *dev);
> struct msm_kms *dpu_kms_init(struct drm_device *dev);
>
> +extern const struct of_device_id dpu_dt_match[];
> +extern const struct of_device_id mdp5_dt_match[];
> +
> struct msm_mdss_funcs {
> int (*enable)(struct msm_mdss *mdss);
> int (*disable)(struct msm_mdss *mdss);
> --
> 2.7.4
>


--
With best wishes
Dmitry