From 66b7be5743d88c9b8fa69e5ba7d06d33d14de8c7 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Sun, 17 Apr 2016 09:39:41 +0200 Subject: [PATCH] ALSA: hda - Don't trust the reported actual power state commit 50fd4987c4f3c3ebf0ce94d932732011bbdc7c71 upstream. We've got a regression report that the recording on Mac with a cirrus codec doesn't work any longer. This turned out to be the missing power up to D0 by power_save_node enablement. After analyzing the traces, we found out that the culprit is that the codec advertises the "actual" power state of a few nodes to be D0 while the "target" power state is D3. This inconsistency is usually OK, as it implies the power transition. But in the case of cirrus codec, this seems to be stuck to D3 while it's not actually D0. This patch addresses the issue by checking the power state difference more strictly. It sends the power-state change verb unless both the target and the actual power states show the given value. We may introduce yet another flag indicating the possible broken hardware power state, but it's anyway safer to set the proper power state even in a transition (at least it's harmless as long as the target state is same). So this simpler change was applied now. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=116171 Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/pci/hda/hda_generic.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/sound/pci/hda/hda_generic.c b/sound/pci/hda/hda_generic.c index 5c4fa8eba1d0..367dbf0d285e 100644 --- a/sound/pci/hda/hda_generic.c +++ b/sound/pci/hda/hda_generic.c @@ -843,7 +843,7 @@ static hda_nid_t path_power_update(struct hda_codec *codec, bool allow_powerdown) { hda_nid_t nid, changed = 0; - int i, state; + int i, state, power; for (i = 0; i < path->depth; i++) { nid = path->path[i]; @@ -855,7 +855,9 @@ static hda_nid_t path_power_update(struct hda_codec *codec, state = AC_PWRST_D0; else state = AC_PWRST_D3; - if (!snd_hda_check_power_state(codec, nid, state)) { + power = snd_hda_codec_read(codec, nid, 0, + AC_VERB_GET_POWER_STATE, 0); + if (power != (state | (state << 4))) { snd_hda_codec_write(codec, nid, 0, AC_VERB_SET_POWER_STATE, state); changed = nid; -- 2.34.1