On Wed, Jan 04, 2023 at 12:05:16PM +0200, Jani Nikula wrote:

We try to avoid sending VICs defined in the later specs in AVI infoframes to sinks that conform to the earlier specs, to not upset them, and use 0 for the VIC instead. However, we do this detection and conversion to 0 too early, as we'll need the actual VIC to figure out the aspect ratio.

In particular, for a mode with 64:27 aspect ratio, 0 for VIC fails the AVI infoframe generation altogether with -EINVAL.

Separate the VIC lookup from the "filtering", and postpone the filtering, to use the proper VIC for aspect ratio handling, and the 0 VIC for the infoframe video code as needed.

Reported-by: William Tseng william.tseng@intel.com Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/6153 References: https://lore.kernel.org/r/20220920062316.43162-1-william.tseng@intel.com Cc: stable@vger.kernel.org Cc: Ville Syrjälä ville.syrjala@linux.intel.com Signed-off-by: Jani Nikula jani.nikula@intel.com

Reviewed-by: Ville Syrjälä ville.syrjala@linux.intel.com

---

drivers/gpu/drm/drm_edid.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 3841aba17abd..23f7146e6a9b 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -6885,8 +6885,6 @@ 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) {

• u8 vic;
• /*
  • HDMI spec says if a mode is found in HDMI 1.4b 4K modes
  • we should send its VIC in vendor infoframes, else send the

@@ -6896,13 +6894,18 @@ static u8 drm_mode_cea_vic(const struct drm_connector *connector, if (drm_mode_hdmi_vic(connector, mode)) return 0;

• vic = drm_match_cea_mode(mode);

• return drm_match_cea_mode(mode);

+}

• /*

• * HDMI 1.4 VIC range: 1 <= VIC <= 64 (CEA-861-D) but
  

• * HDMI 2.0 VIC range: 1 <= VIC <= 107 (CEA-861-F). So we
  

• * have to make sure we dont break HDMI 1.4 sinks.
  

• */
  

+/*

• • Avoid sending VICs defined in HDMI 2.0 in AVI infoframes to sinks that
• • conform to HDMI 1.4.
• • HDMI 1.4 (CTA-861-D) VIC range: [1..64]
• • HDMI 2.0 (CTA-861-F) VIC range: [1..107]
• */

+static u8 vic_for_avi_infoframe(const struct drm_connector *connector, u8 vic) +{ if (!is_hdmi2_sink(connector) && vic > 64) return 0; @@ -6978,7 +6981,7 @@ 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 = vic_for_avi_infoframe(connector, vic); frame->picture_aspect = picture_aspect; frame->active_aspect = HDMI_ACTIVE_ASPECT_PICTURE; frame->scan_mode = HDMI_SCAN_MODE_UNDERSCAN;

-- 2.34.1