drm/amd/display: Flush ISM work before releasing the stream

[Why]
ISM timers are not tied to the atomic commit, so a timer armed before a
DPMS off can still fire after the stream is released. The external display
check in dcn35_apply_idle_power_optimizations() loops over the active
streams, so with none left it never runs and idle is allowed on an
external-only system.

[How]
Wait out pending and in-flight ISM work before dc_stream_release(); dc_lock
is not held there, so the sync wait is safe. Rename amdgpu_dm_ism_fini() to
amdgpu_dm_ism_flush() and assert dc_lock is not held.

Assisted-by: Cursor:Claude-Opus-5
Reviewed-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Ray Wu <ray.wu@amd.com>
Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

0 files changed, 0 insertions, 0 deletions