[ 3.5.y.z extended stable ] Patch "ALSA: usb-audio - Fix invalid volume resolution on Logitech" 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: usb-audio - Fix invalid volume resolution on Logitech

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 4a7adb192b508d9208369c49852e6b0261fb7542 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai at suse.de>
Date: Wed, 5 Jun 2013 08:35:26 +0200
Subject: [PATCH] ALSA: usb-audio - Fix invalid volume resolution on Logitech
 HD webcam c270
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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: Luis Henriques <luis.henriques 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 4d8ddc6..a3308e1 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -842,6 +842,7 @@ 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