ALSA: usb-audio: Fix deadlocks at resuming
authorTakashi Iwai <tiwai@suse.de>
Fri, 2 May 2014 16:17:06 +0000 (18:17 +0200)
committerTakashi Iwai <tiwai@suse.de>
Fri, 2 May 2014 16:17:06 +0000 (18:17 +0200)
commit1ee23fe07ee83a38ecee927e701f762888ada942
treef8af5087956bef2a461410b49584dc3bd2cd988c
parent1c53e7253ed8769a00afa0f06777d731dbe1ba6f
ALSA: usb-audio: Fix deadlocks at resuming

The recent addition of the USB audio mixer suspend/resume may lead to
deadlocks when the driver tries to call usb_autopm_get_interface()
recursively, since the function tries to sync with the finish of the
other calls.  For avoiding it, introduce a flag indicating the resume
operation and avoids the recursive usb_autopm_get_interface() calls
during the resume.

Reported-and-tested-by: Bryan Quigley <gquigs@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
sound/usb/card.c
sound/usb/usbaudio.h