Re: [PATCH v4 26/39] drm/msm/dp: abstract out the dp_display stream helpers to accept a panel

[Dmitry Baryshkov]

On Fri, Apr 10, 2026 at 05:34:01PM +0800, Yongxing Mou wrote:
> From: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
> 
> Currently the dp_display bridge helpers, in particular the
> dp_display_enable()/dp_display_disable() use the cached panel.
> To be able to re-use these helpers for MST use-case abstract the
> helpers to use the panel which is passed in to them.

This commit is doing more than just passing the panel. Please move
relevant parts to the previos one and write a proper commit message for
the rest of the changes.

> 
> Signed-off-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
> Signed-off-by: Yongxing Mou <yongxing.mou@xxxxxxxxxxxxxxxx>
> ---
>  drivers/gpu/drm/msm/dp/dp_display.c | 117 ++++++++++++++++++++++++------------
>  drivers/gpu/drm/msm/dp/dp_display.h |  12 ++++
>  2 files changed, 91 insertions(+), 38 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
> index 88a078e53dc1..33d8539afee7 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -635,12 +635,14 @@ static int msm_dp_display_set_mode(struct msm_dp *msm_dp_display,
>  	return 0;
>  }
>  
> -static int msm_dp_display_prepare(struct msm_dp_display_private *dp)
> +int msm_dp_display_prepare(struct msm_dp *msm_dp_display)
>  {
> -	struct msm_dp *msm_dp_display = &dp->msm_dp_display;
> +	struct msm_dp_display_private *dp;
>  	int rc = 0;
>  	bool force_link_train = false;
>  
> +	dp = container_of(msm_dp_display, struct msm_dp_display_private, msm_dp_display);
> +
>  	drm_dbg_dp(dp->drm_dev, "sink_count=%d\n", dp->link->sink_count);
>  
>  	if (msm_dp_display->is_edp)
> @@ -680,7 +682,7 @@ static int msm_dp_display_enable(struct msm_dp_display_private *dp,
>  		return 0;
>  	}
>  
> -	rc = msm_dp_ctrl_on_stream(dp->ctrl, dp->panel);
> +	rc = msm_dp_ctrl_on_stream(dp->ctrl, msm_dp_panel);
>  	if (!rc)
>  		msm_dp_display->power_on = true;
>  
> @@ -738,18 +740,6 @@ static int msm_dp_display_disable(struct msm_dp_display_private *dp,
>  
>  	msm_dp_ctrl_off_pixel_clk(dp->ctrl, msm_dp_panel->stream_id);
>  
> -	/* dongle is still connected but sinks are disconnected */
> -	if (dp->link->sink_count == 0)
> -		msm_dp_link_psm_config(dp->link, &msm_dp_panel->link_info, true);
> -
> -	msm_dp_ctrl_off_link(dp->ctrl);
> -
> -	if (dp->link->sink_count == 0)
> -		/* re-init the PHY so that we can listen to Dongle disconnect */
> -		msm_dp_ctrl_reinit_phy(dp->ctrl);
> -	else
> -		msm_dp_display_host_phy_exit(dp);
> -
>  	msm_dp_display->power_on = false;
>  
>  	drm_dbg_dp(dp->drm_dev, "sink count: %d\n", dp->link->sink_count);
> @@ -1495,76 +1485,116 @@ int msm_dp_modeset_init(struct msm_dp *msm_dp_display, struct drm_device *dev,
>  	return 0;
>  }
>  
> -void msm_dp_display_atomic_prepare(struct msm_dp *msm_dp_display,
> -				   struct drm_atomic_state *state)
> +int msm_dp_display_set_mode_helper(struct msm_dp *msm_dp_display,
> +				   struct drm_atomic_state *state,
> +				   struct drm_encoder *drm_encoder,
> +				   struct msm_dp_panel *msm_dp_panel)
>  {
>  	struct drm_crtc *crtc;
>  	struct drm_crtc_state *crtc_state;
> +
> +	crtc = drm_atomic_get_new_crtc_for_encoder(state, drm_encoder);
> +	if (!crtc)
> +		return 0;
> +	crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
> +
> +	return msm_dp_display_set_mode(msm_dp_display, &crtc_state->adjusted_mode, msm_dp_panel);
> +}
> +
> +void msm_dp_display_atomic_prepare(struct msm_dp *msm_dp_display,
> +				   struct drm_atomic_state *state)
> +{
>  	int rc = 0;
>  	struct msm_dp_display_private *dp;
>  
>  	dp = container_of(msm_dp_display, struct msm_dp_display_private, msm_dp_display);
>  
> -	crtc = drm_atomic_get_new_crtc_for_encoder(state,
> -						   msm_dp_display->bridge->encoder);
> -	if (!crtc)
> -		return;
> -	crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
> -
> -	rc = msm_dp_display_set_mode(msm_dp_display, &crtc_state->adjusted_mode, dp->panel);
> +	rc = msm_dp_display_set_mode_helper(msm_dp_display, state,
> +					    msm_dp_display->bridge->encoder, dp->panel);
>  	if (rc) {
>  		DRM_ERROR("Failed to perform a mode set, rc=%d\n", rc);
>  		return;
>  	}
>  
> -	rc = msm_dp_display_prepare(dp);
> +	rc = msm_dp_display_prepare(msm_dp_display);
>  	if (rc)
>  		DRM_ERROR("DP display prepare failed, rc=%d\n", rc);
>  }
>  
> -void msm_dp_display_atomic_enable(struct msm_dp *msm_dp_display)
> +void msm_dp_display_enable_helper(struct msm_dp *msm_dp_display, struct msm_dp_panel *msm_dp_panel)
>  {
>  	struct msm_dp_display_private *dp;
>  	int rc = 0;
>  
>  	dp = container_of(msm_dp_display, struct msm_dp_display_private, msm_dp_display);
>  
> -	msm_dp_display_set_stream_info(msm_dp_display, dp->panel, 0, 0, 0, 0);
> -
> -	rc = msm_dp_display_enable(dp, dp->panel);
> +	rc = msm_dp_display_enable(dp, msm_dp_panel);
>  	if (rc)
>  		DRM_ERROR("DP display enable failed, rc=%d\n", rc);
>  
>  	rc = msm_dp_display_post_enable(msm_dp_display);
>  	if (rc) {
>  		DRM_ERROR("DP display post enable failed, rc=%d\n", rc);
> -		msm_dp_display_disable(dp, dp->panel);
> +		msm_dp_display_disable(dp, msm_dp_panel);
>  	}
>  
>  	drm_dbg_dp(msm_dp_display->drm_dev, "type=%d Done\n", msm_dp_display->connector_type);
>  }
>  
> -void msm_dp_display_atomic_disable(struct msm_dp *msm_dp_display)
> +void msm_dp_display_atomic_enable(struct msm_dp *msm_dp_display)
>  {
>  	struct msm_dp_display_private *dp;
>  
>  	dp = container_of(msm_dp_display, struct msm_dp_display_private, msm_dp_display);
>  
> -	msm_dp_ctrl_push_idle(dp->ctrl, dp->panel);
> +	msm_dp_display_set_stream_info(msm_dp_display, dp->panel, 0, 0, 0, 0);
> +
> +	msm_dp_display_enable_helper(msm_dp_display, dp->panel);
> +}
> +
> +void msm_dp_display_disable_helper(struct msm_dp *msm_dp_display,
> +				   struct msm_dp_panel *msm_dp_panel)
> +{
> +	struct msm_dp_display_private *dp;
> +
> +	dp = container_of(msm_dp_display, struct msm_dp_display_private, msm_dp_display);
> +
> +	msm_dp_ctrl_push_idle(dp->ctrl, msm_dp_panel);
>  	msm_dp_ctrl_mst_stream_channel_slot_setup(dp->ctrl);
>  	msm_dp_ctrl_mst_send_act(dp->ctrl);
>  }
>  
> -static void msm_dp_display_unprepare(struct msm_dp_display_private *dp)
> +void msm_dp_display_atomic_disable(struct msm_dp *msm_dp_display)
>  {
> -	struct msm_dp *msm_dp_display = &dp->msm_dp_display;
> +	struct msm_dp_display_private *dp;
>  
> -	pm_runtime_put_sync(&msm_dp_display->pdev->dev);
> +	dp = container_of(msm_dp_display, struct msm_dp_display_private, msm_dp_display);
> +
> +	msm_dp_display_disable_helper(msm_dp_display, dp->panel);
> +}
> +
> +void msm_dp_display_unprepare(struct msm_dp *msm_dp_display)
> +{
> +	struct msm_dp_display_private *dp;
> +
> +	dp = container_of(msm_dp_display, struct msm_dp_display_private, msm_dp_display);
>  
> -	drm_dbg_dp(dp->drm_dev, "type=%d Done\n", msm_dp_display->connector_type);
> +	/* dongle is still connected but sinks are disconnected */
> +	if (dp->link->sink_count == 0)
> +		msm_dp_link_psm_config(dp->link, &dp->panel->link_info, true);
> +
> +	msm_dp_ctrl_off_link(dp->ctrl);
> +
> +	/* re-init the PHY so that we can listen to Dongle disconnect */
> +	if (dp->link->sink_count == 0)
> +		msm_dp_ctrl_reinit_phy(dp->ctrl);
> +	else
> +		msm_dp_display_host_phy_exit(dp);
> +
> +	pm_runtime_put_sync(&msm_dp_display->pdev->dev);
>  }
>  
> -void msm_dp_display_atomic_post_disable(struct msm_dp *dp)
> +void msm_dp_display_atomic_post_disable_helper(struct msm_dp *dp, struct msm_dp_panel *msm_dp_panel)
>  {
>  	struct msm_dp_display_private *msm_dp_display;
>  
> @@ -1575,7 +1605,18 @@ void msm_dp_display_atomic_post_disable(struct msm_dp *dp)
>  
>  	msm_dp_display_audio_notify_disable(msm_dp_display);
>  
> -	msm_dp_display_disable(msm_dp_display, msm_dp_display->panel);
> +	msm_dp_display_disable(msm_dp_display, msm_dp_panel);
> +
> +	drm_dbg_dp(dp->drm_dev, "type=%d Done\n", dp->connector_type);
> +}
> +
> +void msm_dp_display_atomic_post_disable(struct msm_dp *msm_dp_display)
> +{
> +	struct msm_dp_display_private *dp;
> +
> +	dp = container_of(msm_dp_display, struct msm_dp_display_private, msm_dp_display);
> +
> +	msm_dp_display_atomic_post_disable_helper(msm_dp_display, dp->panel);
>  
>  	msm_dp_display_unprepare(msm_dp_display);
>  }
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.h b/drivers/gpu/drm/msm/dp/dp_display.h
> index 0ccdddb223c8..0ede5505be58 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.h
> +++ b/drivers/gpu/drm/msm/dp/dp_display.h
> @@ -46,5 +46,17 @@ enum drm_mode_status msm_dp_display_mode_valid(struct msm_dp *dp,
>  int msm_dp_display_set_stream_info(struct msm_dp *msm_dp_display, struct msm_dp_panel *panel,
>  				   enum msm_dp_stream_id stream_id,
>  				   u32 start_slot, u32 num_slots, u32 pbn);
> +void msm_dp_display_enable_helper(struct msm_dp *msm_dp_display,
> +				  struct msm_dp_panel *msm_dp_panel);
> +void msm_dp_display_disable_helper(struct msm_dp *msm_dp_display,
> +				   struct msm_dp_panel *msm_dp_panel);
> +void msm_dp_display_atomic_post_disable_helper(struct msm_dp *msm_dp_display,
> +					       struct msm_dp_panel *msm_dp_panel);
> +int msm_dp_display_set_mode_helper(struct msm_dp *msm_dp_display,
> +				   struct drm_atomic_state *state,
> +				   struct drm_encoder *drm_encoder,
> +				   struct msm_dp_panel *msm_dp_panel);
> +int msm_dp_display_prepare(struct msm_dp *msm_dp_display);
> +void msm_dp_display_unprepare(struct msm_dp *dp);
>  
>  #endif /* _DP_DISPLAY_H_ */
> 
> -- 
> 2.43.0
> 

-- 
With best wishes
Dmitry