Patch "ALSA: hda - fix "num_steps = 0" error on ALC256" has been added to the 4.0-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    ALSA: hda - fix "num_steps = 0" error on ALC256

to the 4.0-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     alsa-hda-fix-num_steps-0-error-on-alc256.patch
and it can be found in the queue-4.0 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 7d1b6e29327428993ba568bdd8c66734070f45e0 Mon Sep 17 00:00:00 2001
From: David Henningsson <david.henningsson@canonical.com>
Date: Tue, 21 Apr 2015 10:48:46 +0200
Subject: ALSA: hda - fix "num_steps = 0" error on ALC256

From: David Henningsson <david.henningsson@canonical.com>

commit 7d1b6e29327428993ba568bdd8c66734070f45e0 upstream.

The ALC256 does not have a mixer nid at 0x0b, and there's no
loopback path (the output pins are directly connected to the DACs).

This commit fixes an "num_steps = 0 for NID=0xb (ctl = Beep Playback Volume)"
error (and as a result, problems with amixer/alsamixer).

If there's pcbeep functionality, it certainly isn't controlled by setting an
amp on 0x0b, so disable beep functionality (at least for now).

BugLink: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1446517
Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 sound/pci/hda/patch_realtek.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/sound/pci/hda/patch_realtek.c
+++ b/sound/pci/hda/patch_realtek.c
@@ -5565,6 +5565,7 @@ static int patch_alc269(struct hda_codec
 		break;
 	case 0x10ec0256:
 		spec->codec_variant = ALC269_TYPE_ALC256;
+		spec->gen.mixer_nid = 0; /* ALC256 does not have any loopback mixer path */
 		break;
 	}
 
@@ -5578,8 +5579,8 @@ static int patch_alc269(struct hda_codec
 	if (err < 0)
 		goto error;
 
-	if (!spec->gen.no_analog && spec->gen.beep_nid)
-		set_beep_amp(spec, 0x0b, 0x04, HDA_INPUT);
+	if (!spec->gen.no_analog && spec->gen.beep_nid && spec->gen.mixer_nid)
+		set_beep_amp(spec, spec->gen.mixer_nid, 0x04, HDA_INPUT);
 
 	codec->patch_ops = alc_patch_ops;
 #ifdef CONFIG_PM


Patches currently in stable-queue which might be from david.henningsson@canonical.com are

queue-4.0/alsa-hda-fix-num_steps-0-error-on-alc256.patch