[Intel-gfx] [PATCH v4] drm/edid: ignore the CEA modes not defined in CEA-861-D

[William Tseng]

This is a workaround for HDMI 1.4 sink which has a CEA mode with higher vic
than what is defined in CEA-861-D.

As an example, a HDMI 1.4 sink has the video format 2560x1080p to be
displayed and the video format is indicated by both SVD (with vic 90 and
picture aspect ratio 64:27) and DTD.  When connecting to such sink,
source can't output the video format in SVD because an error is returned by
drm_hdmi_avi_infoframe_from_display_mode(), which can't fill the infoframe
with picture aspect ratio 64:27 and the vic, which is originally 90 and is
changed to 0 by drm_mode_cea_vic().

To work around it, do not set the vic 0 so the corresponding mode may be
accepted in drm_hdmi_avi_infoframe_from_display_mode() and be dispalyed.

v1: initial version.
v2: change the logic in drm_hdmi_avi_infoframe_from_display_mode().
v3: fix typo.
v4: add revision history.

Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Cc: Jani Nikula <jani.nikula at linux.intel.com>
Cc: Wayne Lin <waynelin at amd.com>
Cc: Lee Shawn C <shawn.c.lee at intel.com>
Signed-off-by: William Tseng <william.tseng at intel.com>
---
 drivers/gpu/drm/drm_edid.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index eaa819381281..3c6a4e09b2d6 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -6640,7 +6640,8 @@ static u8 drm_mode_hdmi_vic(const struct drm_connector *connector,
 }
 
 static u8 drm_mode_cea_vic(const struct drm_connector *connector,
-			   const struct drm_display_mode *mode)
+			   const struct drm_display_mode *mode,
+			   bool is_hdmi2_sink)
 {
 	u8 vic;
 
@@ -6660,7 +6661,7 @@ static u8 drm_mode_cea_vic(const struct drm_connector *connector,
 	 * HDMI 2.0 VIC range: 1 <= VIC <= 107 (CEA-861-F). So we
 	 * have to make sure we dont break HDMI 1.4 sinks.
 	 */
-	if (!is_hdmi2_sink(connector) && vic > 64)
+	if (!is_hdmi2_sink && vic > 64)
 		return 0;
 
 	return vic;
@@ -6691,7 +6692,7 @@ drm_hdmi_avi_infoframe_from_display_mode(struct hdmi_avi_infoframe *frame,
 	if (mode->flags & DRM_MODE_FLAG_DBLCLK)
 		frame->pixel_repeat = 1;
 
-	vic = drm_mode_cea_vic(connector, mode);
+	vic = drm_mode_cea_vic(connector, mode, true);
 	hdmi_vic = drm_mode_hdmi_vic(connector, mode);
 
 	frame->picture_aspect = HDMI_PICTURE_ASPECT_NONE;
@@ -6735,7 +6736,8 @@ drm_hdmi_avi_infoframe_from_display_mode(struct hdmi_avi_infoframe *frame,
 		picture_aspect = HDMI_PICTURE_ASPECT_NONE;
 	}
 
-	frame->video_code = vic;
+	frame->video_code = drm_mode_cea_vic(connector, mode,
+						is_hdmi2_sink(connector));
 	frame->picture_aspect = picture_aspect;
 	frame->active_aspect = HDMI_ACTIVE_ASPECT_PICTURE;
 	frame->scan_mode = HDMI_SCAN_MODE_UNDERSCAN;
-- 
2.25.1