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.syrj...@linux.intel.com>
Cc: Jani Nikula <jani.nik...@linux.intel.com>
Cc: Wayne Lin <wayne...@amd.com>
Cc: Lee Shawn C <shawn.c....@intel.com>
Signed-off-by: William Tseng <william.ts...@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

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