drm/edid: build ELD in drm_add_edid_modes()

Call drm_edid_to_eld() from drm_add_edid_modes() to fill in the ELD
automatically. There's no harm in doing this for connectors that do not
support audio.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/551b2e1cf19be04c510e7865d7539cfc2f54ea89.1509545641.git.jani.nikula@intel.com

drivers/gpu/drm/drm_edid.c

@@ -4612,8 +4612,8 @@ static int add_displayid_detailed_modes(struct drm_connector *connector,
  * @edid: EDID data
  *
  * Add the specified modes to the connector's mode list. Also fills out the
- * &drm_display_info structure in @connector with any information which can be
- * derived from the edid.
+ * &drm_display_info structure and ELD in @connector with any information which
+ * can be derived from the edid.
  *
  * Return: The number of modes added or 0 if we couldn't find any.
  */
@@ -4623,9 +4623,11 @@ int drm_add_edid_modes(struct drm_connector *connector, struct edid *edid)
 	u32 quirks;
 
 	if (edid == NULL) {
+		clear_eld(connector);
 		return 0;
 	}
 	if (!drm_edid_is_valid(edid)) {
+		clear_eld(connector);
 		dev_warn(connector->dev->dev, "%s: EDID invalid.\n",
 			 connector->name);
 		return 0;
@@ -4633,6 +4635,8 @@ int drm_add_edid_modes(struct drm_connector *connector, struct edid *edid)
 
 	quirks = edid_get_quirks(edid);
 
+	drm_edid_to_eld(connector, edid);
+
 	/*
 	 * CEA-861-F adds ycbcr capability map block, for HDMI 2.0 sinks.
 	 * To avoid multiple parsing of same block, lets parse that map