[PATCH v4] drm/edid: Fill PAR in AVI infoframe based on CEA mode list

[Vandana Kannan]

Populate PAR in infoframe structure. PAR is taken from CEA mode list if
VIC is found. Else, PAR is NONE as per initialization.

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.

v4: Added description for the param video_code. Absence of the description
led to a warning while executing "make htmldocs", as reported by
Wu, Fengguang.
Modified commit message.

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 at intel.com>
Cc: Jesse Barnes <jesse.barnes at intel.com>
Cc: Vijay Purushothaman <vijay.a.purushothaman at intel.com>
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Cc: intel-gfx at lists.freedesktop.org
Cc: Wu, Fengguang <fengguang.wu at intel.com>
Reviewed-by: Jesse Barnes <jbarnes at virtuousgeek.org>
---
 drivers/gpu/drm/drm_edid.c | 22 ++++++++++++++++++++++
 include/drm/drm_crtc.h     |  1 +
 2 files changed, 23 insertions(+)

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 @@ u8 drm_match_cea_mode(const struct drm_display_mode *to_match)
 }
 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 @@ drm_hdmi_avi_infoframe_from_display_mode(struct hdmi_avi_infoframe *frame,
 	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;
 
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 27f828c..50dc55a 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -983,6 +983,7 @@ extern int drm_mode_gamma_get_ioctl(struct drm_device *dev,
 extern int drm_mode_gamma_set_ioctl(struct drm_device *dev,
 				    void *data, struct drm_file *file_priv);
 extern u8 drm_match_cea_mode(const struct drm_display_mode *to_match);
+extern enum hdmi_picture_aspect drm_get_cea_aspect_ratio(const u8 video_code);
 extern bool drm_detect_hdmi_monitor(struct edid *edid);
 extern bool drm_detect_monitor_audio(struct edid *edid);
 extern bool drm_rgb_quant_range_selectable(struct edid *edid);
-- 
1.9.1