drm/edid: Fill PAR in AVI infoframe based on CEA mode list

Populate PAR in infoframe structure. If there is a user setting for PAR, then
that value is set. Else, value is taken from CEA mode list if VIC is found.
Else, PAR is calculated from resolution. If none of these conditions are
satisfied, PAR is NONE as per initialization.

v2: Removed the part which sets PAR according to user input, based on
Daniel's review comments.

A separate patch will be submitted to create a property that would enable a
user space app to set aspect ratio for AVI infoframe.

v2: Removed the part which sets PAR according to user input, based on
Daniel's review comments.

v3: Removed calculation of PAR for non-CEA modes as per discussion with
Ville.

A separate patch will be submitted to create a property that would enable a
user space app to set aspect ratio for AVI infoframe.

Signed-off-by: Vandana Kannan <vandana.kannan@intel.com>
Cc: Jesse Barnes <jesse.barnes@intel.com>
Cc: Vijay Purushothaman <vijay.a.purushothaman@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: intel-gfx@lists.freedesktop.org
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[danvet: Squash in fixup for htmldocs.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index d4e3f9d..b8d6c51 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -2452,6 +2452,22 @@
 }
 EXPORT_SYMBOL(drm_match_cea_mode);
 
+/**
+ * drm_get_cea_aspect_ratio - get the picture aspect ratio corresponding to
+ * the input VIC from the CEA mode list
+ * @video_code: ID given to each of the CEA modes
+ *
+ * Returns picture aspect ratio
+ */
+enum hdmi_picture_aspect drm_get_cea_aspect_ratio(const u8 video_code)
+{
+	/* return picture aspect ratio for video_code - 1 to access the
+	 * right array element
+	*/
+	return edid_cea_modes[video_code-1].picture_aspect_ratio;
+}
+EXPORT_SYMBOL(drm_get_cea_aspect_ratio);
+
 /*
  * Calculate the alternate clock for HDMI modes (those from the HDMI vendor
  * specific block).
@@ -3613,6 +3629,12 @@
 	frame->video_code = drm_match_cea_mode(mode);
 
 	frame->picture_aspect = HDMI_PICTURE_ASPECT_NONE;
+
+	/* Populate picture aspect ratio from CEA mode list */
+	if (frame->video_code > 0)
+		frame->picture_aspect = drm_get_cea_aspect_ratio(
+						frame->video_code);
+
 	frame->active_aspect = HDMI_ACTIVE_ASPECT_PICTURE;
 	frame->scan_mode = HDMI_SCAN_MODE_UNDERSCAN;