[PATCH 2/3] drm/edid: don't log errors on absent CEA SAD blocks

[Jean Delvare]

It is fine for displays without audio functionality to not provide
any SAD block in their EDID. Do not log an error in that case,
just return quietly.

Inspired by a similar fix to the amdgpu driver in the context of bug
fdo#107825:
https://bugs.freedesktop.org/show_bug.cgi?id=107825

Signed-off-by: Jean Delvare <jdelvare at suse.de>
Cc: Alex Deucher <alexander.deucher at amd.com>
Cc: "Christian König" <christian.koenig at amd.com>
Cc: "David (ChunMing) Zhou" <David1.Zhou at amd.com>
Cc: David Airlie <airlied at linux.ie>
Cc: Daniel Vetter <daniel at ffwll.ch>
---
 drivers/gpu/drm/radeon/radeon_audio.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- linux-5.2.orig/drivers/gpu/drm/radeon/radeon_audio.c	2019-08-30 18:04:15.125056697 +0200
+++ linux-5.2/drivers/gpu/drm/radeon/radeon_audio.c	2019-08-30 18:04:35.078311347 +0200
@@ -367,10 +367,10 @@ static void radeon_audio_write_sad_regs(
 		return;
 
 	sad_count = drm_edid_to_sad(radeon_connector_edid(connector), &sads);
-	if (sad_count <= 0) {
+	if (sad_count < 0)
 		DRM_ERROR("Couldn't read SADs: %d\n", sad_count);
+	if (sad_count <= 0)
 		return;
-	}
 	BUG_ON(!sads);
 
 	if (radeon_encoder->audio && radeon_encoder->audio->write_sad_regs)

-- 
Jean Delvare
SUSE L3 Support