[PATCH v2 1/3] drm/amd: be quiet when no SAD block is found

[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.

This fixes half 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>
Cc: Harry Wentland <harry.wentland at amd.com>
Cc: Leo Li <sunpeng.li at amd.com>
---
No change since v1.

 drivers/gpu/drm/amd/amdgpu/dce_v10_0.c                    |    4 ++--
 drivers/gpu/drm/amd/amdgpu/dce_v11_0.c                    |    4 ++--
 drivers/gpu/drm/amd/amdgpu/dce_v6_0.c                     |    4 ++--
 drivers/gpu/drm/amd/amdgpu/dce_v8_0.c                     |    4 ++--
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c |    7 +++----
 5 files changed, 11 insertions(+), 12 deletions(-)

--- linux-5.2.orig/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c	2019-07-08 00:41:56.000000000 +0200
+++ linux-5.2/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c	2019-08-30 14:28:46.081682223 +0200
@@ -1345,10 +1345,10 @@ static void dce_v10_0_audio_write_sad_re
 	}
 
 	sad_count = drm_edid_to_sad(amdgpu_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);
 
 	for (i = 0; i < ARRAY_SIZE(eld_reg_to_type); i++) {
--- linux-5.2.orig/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c	2019-07-08 00:41:56.000000000 +0200
+++ linux-5.2/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c	2019-08-30 14:29:27.276205310 +0200
@@ -1371,10 +1371,10 @@ static void dce_v11_0_audio_write_sad_re
 	}
 
 	sad_count = drm_edid_to_sad(amdgpu_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);
 
 	for (i = 0; i < ARRAY_SIZE(eld_reg_to_type); i++) {
--- linux-5.2.orig/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c	2019-07-08 00:41:56.000000000 +0200
+++ linux-5.2/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c	2019-08-30 17:58:53.613953458 +0200
@@ -1248,10 +1248,10 @@ static void dce_v6_0_audio_write_sad_reg
 	}
 
 	sad_count = drm_edid_to_sad(amdgpu_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;
-	}
 
 	for (i = 0; i < ARRAY_SIZE(eld_reg_to_type); i++) {
 		u32 tmp = 0;
--- linux-5.2.orig/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c	2019-07-08 00:41:56.000000000 +0200
+++ linux-5.2/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c	2019-08-30 14:29:01.948883708 +0200
@@ -1298,10 +1298,10 @@ static void dce_v8_0_audio_write_sad_reg
 	}
 
 	sad_count = drm_edid_to_sad(amdgpu_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);
 
 	for (i = 0; i < ARRAY_SIZE(eld_reg_to_type); i++) {
--- linux-5.2.orig/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c	2019-07-08 00:41:56.000000000 +0200
+++ linux-5.2/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c	2019-08-30 14:31:03.086421910 +0200
@@ -98,11 +98,10 @@ enum dc_edid_status dm_helpers_parse_edi
 			(struct edid *) edid->raw_edid);
 
 	sad_count = drm_edid_to_sad((struct edid *) edid->raw_edid, &sads);
-	if (sad_count <= 0) {
-		DRM_INFO("SADs count is: %d, don't need to read it\n",
-				sad_count);
+	if (sad_count < 0)
+		DRM_ERROR("Couldn't read SADs: %d\n", sad_count);
+	if (sad_count <= 0)
 		return result;
-	}
 
 	edid_caps->audio_mode_count = sad_count < DC_MAX_AUDIO_DESC_COUNT ? sad_count : DC_MAX_AUDIO_DESC_COUNT;
 	for (i = 0; i < edid_caps->audio_mode_count; ++i) {

-- 
Jean Delvare
SUSE L3 Support