[PATCH v2 26/38] drm/msm/dp: skip reading the EDID for MST cases

[Dmitry Baryshkov]

On Mon, Jun 09, 2025 at 08:21:45PM +0800, Yongxing Mou wrote:
> From: Abhinav Kumar <quic_abhinavk at quicinc.com>
> 
> For MST cases, EDID is handled through AUX sideband messaging.
> Skip the EDID read during hotplug handle for MST cases.

Why? It makes sense to read it during the HPD processing, ping HDMI
codec, update CEC info, etc.

> 
> Signed-off-by: Abhinav Kumar <quic_abhinavk at quicinc.com>
> Signed-off-by: Yongxing Mou <quic_yongmou at quicinc.com>
> ---
>  drivers/gpu/drm/msm/dp/dp_display.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
> index 88cae0ca66015377e59bee757462edeae5ae91bf..b1b025d1d356046f8f9e3d243fc774185df24318 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -438,9 +438,11 @@ static int msm_dp_display_process_hpd_high(struct msm_dp_display_private *dp)
>  	if (rc)
>  		goto end;
>  
> -	rc = msm_dp_panel_read_edid(dp->panel, connector);
> -	if (rc)
> -		goto end;
> +	if (!dp->mst_supported || !drm_dp_read_mst_cap(dp->aux, dp->panel->dpcd)) {
> +		rc = msm_dp_panel_read_edid(dp->panel, connector);
> +		if (rc)
> +			goto end;
> +	}
>  
>  	msm_dp_link_process_request(dp->link);
>  
> 
> -- 
> 2.34.1
> 

-- 
With best wishes
Dmitry