[3.8.y.z extended stable] Patch "ALSA: usb-audio: work around KEF X300A firmware bug" 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: work around KEF X300A firmware bug

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 3.8.13.20.

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 1190acddd04cd2c3934f8aca580499b5dcc78d6c Mon Sep 17 00:00:00 2001
From: Clemens Ladisch <clemens at ladisch.de>
Date: Sun, 16 Feb 2014 17:11:10 +0100
Subject: ALSA: usb-audio: work around KEF X300A firmware bug

commit 624aef494f86ed0c58056361c06347ad62b26806 upstream.

When the driver tries to access Function Unit 10, the KEF X300A
speakers' firmware apparently locks up, making even PCM streaming
impossible.  Work around this by ignoring this FU.

Signed-off-by: Clemens Ladisch <clemens at ladisch.de>
Signed-off-by: Takashi Iwai <tiwai at suse.de>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 sound/usb/mixer_maps.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/sound/usb/mixer_maps.c b/sound/usb/mixer_maps.c
index 65e1d7a..87db644 100644
--- a/sound/usb/mixer_maps.c
+++ b/sound/usb/mixer_maps.c
@@ -328,6 +328,11 @@ static struct usbmix_name_map gamecom780_map[] = {
 	{}
 };

+static const struct usbmix_name_map kef_x300a_map[] = {
+	{ 10, NULL }, /* firmware locks up (?) when we try to access this FU */
+	{ 0 }
+};
+
 /*
  * Control map entries
  */
@@ -415,6 +420,10 @@ static struct usbmix_ctl_map usbmix_ctl_maps[] = {
 		.id = USB_ID(0x200c, 0x1018),
 		.map = ebox44_map,
 	},
+	{
+		.id = USB_ID(0x27ac, 0x1000),
+		.map = kef_x300a_map,
+	},
 	{ 0 } /* terminator */
 };

--
1.8.3.2