drm/amd/display: add DP protocol version

[Why]
We want to know DP protocol version

[How]
In DC create we initialize a cap to indicate the max
DP protocol version supported
Signed-off-by: Anthony Koo <Anthony.Koo@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc.c

@@ -809,6 +809,8 @@ struct dc *dc_create(const struct dc_init_data *init_params)
 	dc->caps.max_audios = dc->res_pool->audio_count;
 	dc->caps.linear_pitch_alignment = 64;
 
+	dc->caps.max_dp_protocol_version = DP_VERSION_1_4;
+
 	/* Populate versioning information */
 	dc->versions.dc_ver = DC_VER;
 

drivers/gpu/drm/amd/display/dc/dc.h

@@ -54,6 +54,10 @@ struct dc_versions {
 	struct dmcu_version dmcu_version;
 };
 
+enum dp_protocol_version {
+	DP_VERSION_1_4,
+};
+
 enum dc_plane_type {
 	DC_PLANE_TYPE_INVALID,
 	DC_PLANE_TYPE_DCE_RGB,
@@ -114,6 +118,7 @@ struct dc_caps {
 	bool extended_aux_timeout_support;
 	bool dmcub_support;
 	bool hw_3d_lut;
+	enum dp_protocol_version max_dp_protocol_version;
 	struct dc_plane_cap planes[MAX_PLANES];
 };