[alsa-devel] [PATCH bugfix v3.4] ALSA: hda - fix "silence after S3" regression

[Konstantin Khlebnikov]

This fixes regression in shd-hda-codec after 785f857d1cb0856b612b46a0545b74aa2
("ALSA: hda - Set codec to D3 forcibly even if not used")

hda_set_power_state() call must be explicitly protected against recursive
snd_hda_power_up/down() calls, otherwise it accidentally switches device into
D0 right before suspend. As result after resume sound device stays in D3 state
and does not works because driver believes that the device is on already.

Signed-off-by: Konstantin Khlebnikov <khlebnikov at openvz.org>
---
 sound/pci/hda/hda_codec.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
index 7a8fcc4..a0ea9d6 100644
--- a/sound/pci/hda/hda_codec.c
+++ b/sound/pci/hda/hda_codec.c
@@ -5444,10 +5444,14 @@ int snd_hda_suspend(struct hda_bus *bus)
 	list_for_each_entry(codec, &bus->codec_list, list) {
 		if (hda_codec_is_power_on(codec))
 			hda_call_codec_suspend(codec);
-		else /* forcibly change the power to D3 even if not used */
+		else {
+			/* forcibly change the power to D3 even if not used */
+			codec->power_transition = 1;
 			hda_set_power_state(codec,
 					    codec->afg ? codec->afg : codec->mfg,
 					    AC_PWRST_D3);
+			codec->power_transition = 0;
+		}
 		if (codec->patch_ops.post_suspend)
 			codec->patch_ops.post_suspend(codec);
 	}