drm/msm/dp: check if VSC SDP is supported in DP programming

In the DP driver, check if VSC SDP is supported and propagate this value
to dp_panel. In dp_display's dp_mode, the out_fmt_is_yuv_420 parameter
must also utilize this value since YUV420 is only allowed when VSC SDP
is supported.

Changes in v2:
	- Move DP programming when VSC SDP is supported to this patch
Signed-off-by: Paloma Arellano <quic_parellan@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/579625/
Link: https://lore.kernel.org/r/20240222194025.25329-9-quic_parellan@quicinc.comSigned-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

drivers/gpu/drm/msm/dp/dp_display.c

@@ -1550,8 +1550,10 @@ void dp_bridge_mode_set(struct drm_bridge *drm_bridge,
 	struct msm_dp_bridge *dp_bridge = to_dp_bridge(drm_bridge);
 	struct msm_dp *dp = dp_bridge->dp_display;
 	struct dp_display_private *dp_display;
+	struct dp_panel *dp_panel;
 
 	dp_display = container_of(dp, struct dp_display_private, dp_display);
+	dp_panel = dp_display->panel;
 
 	memset(&dp_display->dp_mode, 0x0, sizeof(struct dp_display_mode));
 
@@ -1572,7 +1574,8 @@ void dp_bridge_mode_set(struct drm_bridge *drm_bridge,
 		!!(dp_display->dp_mode.drm_mode.flags & DRM_MODE_FLAG_NHSYNC);
 
 	dp_display->dp_mode.out_fmt_is_yuv_420 =
-		drm_mode_is_420_only(&dp->connector->display_info, adjusted_mode);
+		drm_mode_is_420_only(&dp->connector->display_info, adjusted_mode) &&
+		dp_panel->vsc_sdp_supported;
 
 	/* populate wide_bus_support to different layers */
 	dp_display->ctrl->wide_bus_en =

drivers/gpu/drm/msm/dp/dp_panel.c

@@ -57,6 +57,7 @@ static int dp_panel_read_dpcd(struct dp_panel *dp_panel)
 	if (rc)
 		return rc;
 
+	dp_panel->vsc_sdp_supported = drm_dp_vsc_sdp_supported(panel->aux, dpcd);
 	link_info = &dp_panel->link_info;
 	link_info->revision = dpcd[DP_DPCD_REV];
 	major = (link_info->revision >> 4) & 0x0f;

drivers/gpu/drm/msm/dp/dp_panel.h

@@ -46,6 +46,7 @@ struct dp_panel {
 	struct dp_display_mode dp_mode;
 	struct dp_panel_psr psr_cap;
 	bool video_test;
+	bool vsc_sdp_supported;
 
 	u32 vic;
 	u32 max_dp_lanes;