ALSA: usb - fix race in creation of M-Audio Fast track pro driver
authorDavid Henningsson <david.henningsson@canonical.com>
Fri, 4 Jan 2013 16:02:18 +0000 (17:02 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 21 Jan 2013 19:45:24 +0000 (11:45 -0800)
commitee415da5538413edc5d63c07899abc0b2b36bc54
treebb974df2a43c028a23eb256623bae7fc130da0f2
parentd2e42ef98559ce48a516d40b64a7a489676d69f0
ALSA: usb - fix race in creation of M-Audio Fast track pro driver

commit b98ae2729dea161edc96c9d177459b6c28bcbba5 upstream.

A patch in the 3.2 kernel caused regression with hotplugging the
M-Audio Fast track pro, or sound after suspend. I don't have the
device so I haven't done a full analysis, but it seems userspace
(both udev and pulseaudio) got confused when a card was created,
immediately destroyed, and then created again.

However, at least one person in the bug report (martin djfun)
reports that this patch resolves the issue for him. It also leaves
a message in the log:
"snd-usb-audio: probe of 1-1.1:1.1 failed with error -5" which is
a bit misleading. It is better than non-working audio, but maybe
there's a more elegant solution?

BugLink: https://bugs.launchpad.net/bugs/1095315
Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: CAI Qian <caiqian@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sound/usb/quirks.c