drm/msm: add support for parsing YUV 420 deep color

Current upstream parser only handles RGB deep color
modes.

Add support in the SDE EDID parser module to parse
HDMI VSDB block and indicate support for YUV 420
deep color modes in the sink.

Change-Id: If6c007263094e7716a29cae503d3e3471ae04306
Signed-off-by: Abhinav Kumar <abhinavk@codeaurora.org>

2 files changed, 78 insertions, 0 deletions

diff --git a/drivers/gpu/drm/msm/sde_edid_parser.c b/drivers/gpu/drm/msm/sde_edid_parser.c
index 69ab367307ea..ca9229ede251 100644
--- a/drivers/gpu/drm/msm/sde_edid_parser.c
+++ b/drivers/gpu/drm/msm/sde_edid_parser.c
@@ -93,6 +93,21 @@ for ((i) = (start); \
 (i) < (end) && (i) + sde_cea_db_payload_len(&(cea)[(i)]) < (end); \
 (i) += sde_cea_db_payload_len(&(cea)[(i)]) + 1)
 
+static bool sde_cea_db_is_hdmi_hf_vsdb(const u8 *db)
+{
+	int hdmi_id;
+
+	if (sde_cea_db_tag(db) != VENDOR_SPECIFIC_DATA_BLOCK)
+		return false;
+
+	if (sde_cea_db_payload_len(db) < 7)
+		return false;
+
+	hdmi_id = db[1] | (db[2] << 8) | (db[3] << 16);
+
+	return hdmi_id == HDMI_IEEE_OUI_HF;
+}
+
 static u8 *sde_edid_find_extended_tag_block(struct edid *edid, int blk_id)
 {
 	u8 *db = NULL;
@@ -339,6 +354,63 @@ struct drm_connector *connector, struct sde_edid_ctrl *edid_ctrl)
 	SDE_EDID_DEBUG("%s -\n", __func__);
 }
 
+static void _sde_edid_update_dc_modes(
+struct drm_connector *connector, struct sde_edid_ctrl *edid_ctrl)
+{
+	int i, start, end;
+	u8 *edid_ext, *hdmi;
+	struct drm_display_info *disp_info;
+	u32 hdmi_dc_yuv_modes = 0;
+
+	SDE_EDID_DEBUG("%s +\n", __func__);
+
+	if (!connector || !edid_ctrl) {
+		SDE_ERROR("invalid input\n");
+		return;
+	}
+
+	disp_info = &connector->display_info;
+
+	edid_ext = sde_find_cea_extension(edid_ctrl->edid);
+
+	if (!edid_ext) {
+		SDE_ERROR("no cea extension\n");
+		return;
+	}
+
+	if (sde_cea_db_offsets(edid_ext, &start, &end))
+		return;
+
+	sde_for_each_cea_db(edid_ext, i, start, end) {
+		if (sde_cea_db_is_hdmi_hf_vsdb(&edid_ext[i])) {
+
+			hdmi = &edid_ext[i];
+
+			if (sde_cea_db_payload_len(hdmi) < 7)
+				continue;
+
+			if (hdmi[7] & DRM_EDID_YCBCR420_DC_30) {
+				hdmi_dc_yuv_modes |= DRM_EDID_YCBCR420_DC_30;
+				SDE_EDID_DEBUG("Y420 30-bit supported\n");
+			}
+
+			if (hdmi[7] & DRM_EDID_YCBCR420_DC_36) {
+				hdmi_dc_yuv_modes |= DRM_EDID_YCBCR420_DC_36;
+				SDE_EDID_DEBUG("Y420 36-bit supported\n");
+			}
+
+			if (hdmi[7] & DRM_EDID_YCBCR420_DC_48) {
+				hdmi_dc_yuv_modes |= DRM_EDID_YCBCR420_DC_36;
+				SDE_EDID_DEBUG("Y420 48-bit supported\n");
+			}
+		}
+	}
+
+	disp_info->edid_hdmi_dc_modes |= hdmi_dc_yuv_modes;
+
+	SDE_EDID_DEBUG("%s -\n", __func__);
+}
+
 static void _sde_edid_extract_audio_data_blocks(
 	struct sde_edid_ctrl *edid_ctrl)
 {
@@ -476,6 +548,7 @@ int _sde_edid_update_modes(struct drm_connector *connector,
 
 		rc = drm_add_edid_modes(connector, edid_ctrl->edid);
 		sde_edid_set_mode_format(connector, edid_ctrl);
+		_sde_edid_update_dc_modes(connector, edid_ctrl);
 		SDE_EDID_DEBUG("%s -", __func__);
 		return rc;
 	}
diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h
index 4317ea41382f..69cb2ba37116 100644
--- a/include/drm/drm_edid.h
+++ b/include/drm/drm_edid.h
@@ -209,6 +209,11 @@ struct detailed_timing {
 #define DRM_EDID_HDMI_DC_30               (1 << 4)
 #define DRM_EDID_HDMI_DC_Y444             (1 << 3)
 
+/* YCBCR 420 deep color modes */
+#define DRM_EDID_YCBCR420_DC_48  (1 << 2)
+#define DRM_EDID_YCBCR420_DC_36  (1 << 1)
+#define DRM_EDID_YCBCR420_DC_30  (1 << 0)
+
 /* ELD Header Block */
 #define DRM_ELD_HEADER_BLOCK_SIZE	4