[ 3.8.y.z extended stable ] Patch "ALSA: usb-audio - Fix invalid volume resolution on Logitech HD webcam" has been added to staging queue

[Kamal Mostafa]

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

    ALSA: usb-audio - Fix invalid volume resolution on Logitech HD webcam

to the linux-3.8.y-queue branch of the 3.8.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-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.3.

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

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From e01d05f5a17d431842716cc3c748d5a23bd7289e Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai at suse.de>
Date: Wed, 5 Jun 2013 08:35:26 +0200
Subject: ALSA: usb-audio - Fix invalid volume resolution on Logitech HD webcam
 c270
MIME-Version: 1.0
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Content-Transfer-Encoding: 8bit

commit 11e7064f35bb87da8f427d1aa4bbd8b7473a3993 upstream.

USB audio driver spews an error message when probing Logitech HD
webcam c270:
  ALSA mixer.c:1300 usb_audio: Warning! Unlikely big volume range (=6144), cval->res is probably wrong.
  ALSA mixer.c:1304 usb_audio: [5] FU [Mic Capture Volume] ch = 1, val = 1536/7680/1

Obviously the device needs a fixed volume resolution (cval->res = 384)
like other Logitech devices.

Bugzilla: https://bugzilla.novell.com/show_bug.cgi?id=821735

Reported-and-tested-by: Cristian Rodríguez <crrodriguez at opensuse.org>
Signed-off-by: Takashi Iwai <tiwai at suse.de>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 sound/usb/mixer.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index 64a564d..0a1e869 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -885,6 +885,7 @@ static void volume_control_quirks(struct usb_mixer_elem_info *cval,
 	case USB_ID(0x046d, 0x0808):
 	case USB_ID(0x046d, 0x0809):
 	case USB_ID(0x046d, 0x081d): /* HD Webcam c510 */
+	case USB_ID(0x046d, 0x0825): /* HD Webcam c270 */
 	case USB_ID(0x046d, 0x0991):
 	/* Most audio usb devices lie about volume resolution.
 	 * Most Logitech webcams have res = 384.
--
1.8.1.2