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