drm/edid: parse source physical address

CEC needs the source physical address. Parsing it is trivial with the
existing EDID CEA DB infrastructure.

Default to CEC_PHYS_ADDR_INVALID (0xffff) instead of 0 to cater for
easier CEC usage.

Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: linux-media@vger.kernel.org
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/8c6b6403932536b6849e0b44e1ee6e7ebdbe4a69.1692884619.git.jani.nikula@intel.com

drivers/gpu/drm/drm_edid.c

@@ -29,6 +29,7 @@
  */
 
 #include <linux/bitfield.h>
+#include <linux/cec.h>
 #include <linux/hdmi.h>
 #include <linux/i2c.h>
 #include <linux/kernel.h>
@@ -6205,6 +6206,8 @@ drm_parse_hdmi_vsdb_video(struct drm_connector *connector, const u8 *db)
 
 	info->is_hdmi = true;
 
+	info->source_physical_address = (db[4] << 8) | db[5];
+
 	if (len >= 6)
 		info->dvi_dual = db[6] & 1;
 	if (len >= 7)
@@ -6483,6 +6486,8 @@ static void drm_reset_display_info(struct drm_connector *connector)
 	info->vics_len = 0;
 
 	info->quirks = 0;
+
+	info->source_physical_address = CEC_PHYS_ADDR_INVALID;
 }
 
 static void update_displayid_info(struct drm_connector *connector,

include/drm/drm_connector.h

@@ -816,6 +816,14 @@ struct drm_display_info {
 	 * @quirks: EDID based quirks. Internal to EDID parsing.
 	 */
 	u32 quirks;
+
+	/**
+	 * @source_physical_address: Source Physical Address from HDMI
+	 * Vendor-Specific Data Block, for CEC usage.
+	 *
+	 * Defaults to CEC_PHYS_ADDR_INVALID (0xffff).
+	 */
+	u16 source_physical_address;
 };
 
 int drm_display_info_set_bus_formats(struct drm_display_info *info,