[PATCH] ALSA: hda/hdmi: Consider ELD is invalid when no SAD is present

[Kai-Heng Feng]

There's a system that reports a bogus HDMI audio interface:
$ cat eld#2.0
monitor_present         1
eld_valid               1
monitor_name
connection_type         DisplayPort
eld_version             [0x2] CEA-861D or below
edid_version            [0x3] CEA-861-B, C or D
manufacture_id          0xe430
product_id              0x690
port_id                 0x0
support_hdcp            0
support_ai              0
audio_sync_delay        0
speakers                [0xffff] FL/FR LFE FC RL/RR RC FLC/FRC RLC/RRC FLW/FRW FLH/FRH TC FCH
sad_count               0

Since playing audio is not possible without SAD, also consider ELD is
invalid for this case.

Signed-off-by: Kai-Heng Feng <kai.heng.feng at canonical.com>
---
 sound/pci/hda/patch_hdmi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index 415701bd10ac8..e7c2f3167f311 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -1535,7 +1535,7 @@ static void update_eld(struct hda_codec *codec,
 		}
 	}
 
-	if (!eld->eld_valid || eld->eld_size <= 0) {
+	if (!eld->eld_valid || eld->eld_size <= 0 || eld->info.sad_count <= 0) {
 		eld->eld_valid = false;
 		eld->eld_size = 0;
 	}
-- 
2.32.0