[PATCH v2] drm/amd/display: Don't warn about vendor infoframe for non-infoframe sinks

[PATCH v2] drm/amd/display: Don't warn about vendor infoframe for non-infoframe sinks

[Paul Menzel]

With an EIZO EV2781 connected over HDMI to an AMD Ryzen 3 2200G (Raven)
on an MSI B350M MORTAR (MS-7A37), Linux logs at every boot since v6.16:

    amdgpu 0000:30:00.0: [drm] Failed to setup vendor infoframe on connector HDMI-A-1: -22

Commit 6027cbee1900 ("drm/amd/display: Add error check for avi and
vendor infoframe setup function") started to log the return value of
drm_hdmi_vendor_infoframe_from_display_mode(). With `frame` and `mode`
being non-NULL, the helper only fails with -EINVAL, if the sink does
not support HDMI infoframes, that means, if
`connector->display_info.has_hdmi_infoframe` is false, and its
kernel-doc says, that this error can be safely ignored.
drm_parse_hdmi_vsdb_video() only sets `has_hdmi_infoframe`, if the HDMI
VSDB has HDMI_Video_present set, and drm_parse_hdmi_forum_scds() sets
it for sinks with an HF-SCDB. So an HDMI sink, whose VSDB lacks
HDMI_Video_present, triggers the warning, although nothing failed.

The EIZO EV2781 is such a sink. Its HDMI VSDB has a payload of only
seven bytes (source physical address, Supports_AI, and a maximum TMDS
clock of 250 MHz), so the byte with HDMI_Video_present is absent, and
the EDID has no HF-SCDB:

    67 03 0c 00 10 00 80 32

Only warn, if the sink supports HDMI infoframes. The infoframe setup
itself is unchanged.

Fixes: 6027cbee1900 ("drm/amd/display: Add error check for avi and vendor infoframe setup function")
Closes: https://gitlab.freedesktop.org/drm/amd/-/work_items/5025
Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
---

v1 → v2: Add Signed-off-by line.

Notes:

claude-opus-5-5 (Claude Code) assisted in analysis, code change and
commit message.

 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_connector.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_connector.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_connector.c
index ded8e21897f1c..636dd2dedd73d 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_connector.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_connector.c
@@ -941,7 +941,8 @@ STATIC_IFN_KUNIT void fill_stream_properties_from_drm_display_mode(
 		err = drm_hdmi_vendor_infoframe_from_display_mode(&hv_frame,
 								  (struct drm_connector *)connector,
 								  mode_in);
-		if (err < 0)
+		/* Sinks without HDMI infoframe support make it fail with -EINVAL. */
+		if (err < 0 && info->has_hdmi_infoframe)
 			drm_warn_once(connector->dev, "Failed to setup vendor infoframe on connector %s: %zd\n",
 				      connector->name, err);
 		timing_out->hdmi_vic = hv_frame.vic;

base-commit: 77f548b127c6de34ce271fa09ba270cb1ef9f2da
-- 
2.54.0