[PATCH V2 3/4] drm/panel: Add prepare_upstream_first flag to drm_panel

[Dmitry Baryshkov]

On 04/03/2022 18:17, Dave Stevenson wrote:
> Mapping to the drm_bridge flag pre_enable_upstream_first,
> add a new flag prepare_upstream_first to drm_panel to allow
> the panel driver to request that the upstream bridge should
> be pre_enabled before the panel prepare.
> 
> Signed-off-by: Dave Stevenson <dave.stevenson at raspberrypi.com>

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>

> ---
>   drivers/gpu/drm/bridge/panel.c |  3 +++
>   include/drm/drm_panel.h        | 10 ++++++++++
>   2 files changed, 13 insertions(+)
> 
> diff --git a/drivers/gpu/drm/bridge/panel.c b/drivers/gpu/drm/bridge/panel.c
> index 5be057575183..2ea08b3ba326 100644
> --- a/drivers/gpu/drm/bridge/panel.c
> +++ b/drivers/gpu/drm/bridge/panel.c
> @@ -234,6 +234,9 @@ struct drm_bridge *drm_panel_bridge_add_typed(struct drm_panel *panel,
>   	panel_bridge->bridge.ops = DRM_BRIDGE_OP_MODES;
>   	panel_bridge->bridge.type = connector_type;
>   
> +	panel_bridge->bridge.pre_enable_upstream_first =
> +						panel->prepare_upstream_first;
> +
>   	drm_bridge_add(&panel_bridge->bridge);
>   
>   	return &panel_bridge->bridge;
> diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
> index 1ba2d424a53f..c0f39dfbd071 100644
> --- a/include/drm/drm_panel.h
> +++ b/include/drm/drm_panel.h
> @@ -179,6 +179,16 @@ struct drm_panel {
>   	 * Panel entry in registry.
>   	 */
>   	struct list_head list;
> +
> +	/**
> +	 * @prepare_upstream_first:
> +	 *
> +	 * The upstream controller should be prepared first, before the prepare
> +	 * for the panel is called. This is largely required for DSI panels
> +	 * where the DSI host controller should be initialised to LP-11 before
> +	 * the panel is powered up.
> +	 */
> +	bool prepare_upstream_first;
>   };
>   
>   void drm_panel_init(struct drm_panel *panel, struct device *dev,


-- 
With best wishes
Dmitry