[3.16.y-ckt stable] Patch "ALSA: hda - Fix headphone noise after Dell XPS 13 resume back from S3" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    ALSA: hda - Fix headphone noise after Dell XPS 13 resume back from S3

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt22.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 3f6427b846419f2a54fcdd3e0d43bf0586f771e3 Mon Sep 17 00:00:00 2001
From: Hui Wang <hui.wang at canonical.com>
Date: Tue, 24 Nov 2015 11:08:18 +0800
Subject: ALSA: hda - Fix headphone noise after Dell XPS 13 resume back from S3

commit 8c69729b4439bbda88c3073df7243f755cc418ed upstream.

We have a machine Dell XPS 13 with the codec alc256, after resume back
from S3, the headphone has noise when play sound.

Through comparing with the coeff vaule before and after S3, we found
restoring a coeff register will help remove noise.

BugLink: https://bugs.launchpad.net/bugs/1519168
Cc: Kailang Yang <kailang at realtek.com>
Signed-off-by: Hui Wang <hui.wang at canonical.com>
Signed-off-by: Takashi Iwai <tiwai at suse.de>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 sound/pci/hda/patch_realtek.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c
index e78193d905d9..379ece8c3afc 100644
--- a/sound/pci/hda/patch_realtek.c
+++ b/sound/pci/hda/patch_realtek.c
@@ -4318,6 +4318,7 @@ enum {
 	ALC292_FIXUP_TPT440_DOCK,
 	ALC292_FIXUP_TPT440_DOCK2,
 	ALC275_FIXUP_DELL_XPS,
+	ALC256_FIXUP_DELL_XPS_13_HEADPHONE_NOISE,
 };

 static const struct hda_fixup alc269_fixups[] = {
@@ -4781,6 +4782,17 @@ static const struct hda_fixup alc269_fixups[] = {
 			{}
 		}
 	},
+	[ALC256_FIXUP_DELL_XPS_13_HEADPHONE_NOISE] = {
+		.type = HDA_FIXUP_VERBS,
+		.v.verbs = (const struct hda_verb[]) {
+			/* Disable pass-through path for FRONT 14h */
+			{0x20, AC_VERB_SET_COEF_INDEX, 0x36},
+			{0x20, AC_VERB_SET_PROC_COEF, 0x1737},
+			{}
+		},
+		.chained = true,
+		.chain_id = ALC255_FIXUP_DELL1_MIC_NO_PRESENCE
+	},
 };

 static const struct snd_pci_quirk alc269_fixup_tbl[] = {
@@ -4845,6 +4857,7 @@ static const struct snd_pci_quirk alc269_fixup_tbl[] = {
 	SND_PCI_QUIRK(0x1028, 0x15cd, "Dell X5 Precision", ALC269_FIXUP_DELL2_MIC_NO_PRESENCE),
 	SND_PCI_QUIRK(0x1028, 0x06d9, "Dell", ALC293_FIXUP_DELL1_MIC_NO_PRESENCE),
 	SND_PCI_QUIRK(0x1028, 0x06da, "Dell", ALC293_FIXUP_DELL1_MIC_NO_PRESENCE),
+	SND_PCI_QUIRK(0x1028, 0x0704, "Dell XPS 13", ALC256_FIXUP_DELL_XPS_13_HEADPHONE_NOISE),
 	SND_PCI_QUIRK(0x1028, 0x164a, "Dell", ALC293_FIXUP_DELL1_MIC_NO_PRESENCE),
 	SND_PCI_QUIRK(0x1028, 0x164b, "Dell", ALC293_FIXUP_DELL1_MIC_NO_PRESENCE),
 	SND_PCI_QUIRK(0x103c, 0x1586, "HP", ALC269_FIXUP_HP_MUTE_LED_MIC2),