[3.5.y.z extended stable] Patch "ALSA: hda - Add enable_msi=0 workaround for four HP machines" 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 - Add enable_msi=0 workaround for four HP machines

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

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

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 3c57ba753106fee36c11859f20d2529ef32a672d Mon Sep 17 00:00:00 2001
From: David Henningsson <david.henningsson at canonical.com>
Date: Thu, 12 Dec 2013 09:52:03 +0100
Subject: ALSA: hda - Add enable_msi=0 workaround for four HP machines

commit 693e0cb052c607e2d41edf9e9f1fa99ff8c266c1 upstream.

While enabling these machines, we found we would sometimes lose an
interrupt if we change hardware volume during playback, and that
disabling msi fixed this issue. (Losing the interrupt caused underruns
and crackling audio, as the one second timeout is usually bigger than
the period size.)

The machines were all machines from HP, running AMD Hudson controller,
and Realtek ALC282 codec.

BugLink: https://bugs.launchpad.net/bugs/1260225
Signed-off-by: David Henningsson <david.henningsson at canonical.com>
Signed-off-by: Takashi Iwai <tiwai at suse.de>
[ luis: backported to 3.5: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 sound/pci/hda/hda_intel.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index c4b29d4..d13662f 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -2809,6 +2809,10 @@ static void __devinit check_probe_mask(struct azx *chip, int dev)
  * white/black-list for enable_msi
  */
 static struct snd_pci_quirk msi_black_list[] __devinitdata = {
+	SND_PCI_QUIRK(0x103c, 0x2191, "HP", 0), /* AMD Hudson */
+	SND_PCI_QUIRK(0x103c, 0x2192, "HP", 0), /* AMD Hudson */
+	SND_PCI_QUIRK(0x103c, 0x21f7, "HP", 0), /* AMD Hudson */
+	SND_PCI_QUIRK(0x103c, 0x21fa, "HP", 0), /* AMD Hudson */
 	SND_PCI_QUIRK(0x1043, 0x81f2, "ASUS", 0), /* Athlon64 X2 + nvidia */
 	SND_PCI_QUIRK(0x1043, 0x81f6, "ASUS", 0), /* nvidia */
 	SND_PCI_QUIRK(0x1043, 0x822d, "ASUS", 0), /* Athlon64 X2 + nvidia MCP55 */
--
1.8.3.2