drm/dp_helper: Add helper to check DSC support with given o/p format

Add helper to check if the DP sink supports DSC with the given
o/p format.

v2: Add documentation for the helper. (Uma Shankar)

v3: /** instead of  /* (Uma Shankar)
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230309062855.393087-2-suraj.kandpal@intel.com

include/drm/display/drm_dp_helper.h

@@ -194,6 +194,19 @@ drm_dp_dsc_sink_max_slice_width(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE])
 		DP_DSC_SLICE_WIDTH_MULTIPLIER;
 }
 
+/**
+ * drm_dp_dsc_sink_supports_format() - check if sink supports DSC with given output format
+ * @dsc_dpcd : DSC-capability DPCDs of the sink
+ * @output_format: output_format which is to be checked
+ *
+ * Returns true if the sink supports DSC with the given output_format, false otherwise.
+ */
+static inline bool
+drm_dp_dsc_sink_supports_format(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_SIZE], u8 output_format)
+{
+	return dsc_dpcd[DP_DSC_DEC_COLOR_FORMAT_CAP - DP_DSC_SUPPORT] & output_format;
+}
+
 /* Forward Error Correction Support on DP 1.4 */
 static inline bool
 drm_dp_sink_supports_fec(const u8 fec_capable)