Better diagnostic when VIDIOC_S_EXT_CTRLS returns < 0: read
back error_idx and print which control id rejected (or
"ioctl-level" when error_idx == count, meaning the rejection
was generic, not per-control).
Made it possible to triage the daedalus_v4l2 phase 8.13 issue
by separating "the actual stateless control failed" (would
show failing_ctrl_id=0xa40a2c VP9_FRAME) from "libva probing
H264/HEVC profile/level we don't expose" (failing_ctrl_id=
0xa40900 H264_PROFILE etc.) — the latter is harmless on a
VP9-only context.
Before:
v4l2-request: Unable to set control(s): Invalid argument
After (per-control):
v4l2-request: Unable to set control(s): Invalid argument
(error_idx=0/2 failing_ctrl_id=0xa40900 size=0)
After (ioctl-level):
v4l2-request: Unable to set control(s): Invalid argument
(error_idx=2/2 ioctl-level)
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
marfrit
de27e95571