[PATCH 5.10 12/33] drm/amd/display: Fix for the no Audio bug with Tiled Displays

From: Greg Kroah-Hartman
Date: Wed Dec 15 2021 - 12:25:34 EST


From: Mustapha Ghaddar <mghaddar@xxxxxxx>

[ Upstream commit 5ceaebcda9061c04f439c93961f0819878365c0f ]

[WHY]
It seems like after a series of plug/unplugs we end up in a situation
where tiled display doesnt support Audio.

[HOW]
The issue seems to be related to when we check streams changed after an
HPD, we should be checking the audio_struct as well to see if any of its
values changed.

Reviewed-by: Jun Lei <Jun.Lei@xxxxxxx>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@xxxxxxx>
Signed-off-by: Mustapha Ghaddar <mustapha.ghaddar@xxxxxxx>
Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/amd/display/dc/core/dc_resource.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
index 59d48cf819ea8..5f4cdb05c4db9 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -1698,6 +1698,10 @@ bool dc_is_stream_unchanged(
if (old_stream->ignore_msa_timing_param != stream->ignore_msa_timing_param)
return false;

+ // Only Have Audio left to check whether it is same or not. This is a corner case for Tiled sinks
+ if (old_stream->audio_info.mode_count != stream->audio_info.mode_count)
+ return false;
+
return true;
}

--
2.33.0