The commit [
9bef72bdb26e: ALSA: pcxhr: Use nonatomic PCM ops]
converted to non-atomic PCM ops, but shamelessly with an unbalanced
mutex locking, which leads to the hangup easily.  Fix it.
Fixes: 9bef72bdb26e ('ALSA: pcxhr: Use nonatomic PCM ops')
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=116441
Cc: <stable@vger.kernel.org> # 3.18+
Signed-off-by: Takashi Iwai <tiwai@suse.de>
        }
 
        pcxhr_msg_thread(mgr);
+       mutex_unlock(&mgr->lock);
        return IRQ_HANDLED;
 }