ALSA: line6: Drop superfluous spinlock for trigger

The trigger callback is already spinlocked, so we need no more lock
here (even for the linked substreams).  Let's drop it.

Tested-by: Chris Rorvick <chris@rorvick.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

2 files changed, 6 insertions, 22 deletions

diff --git a/sound/usb/line6/pcm.c b/sound/usb/line6/pcm.c
index 9a2a15f4c4e4..adbcac46b785 100644
--- a/sound/usb/line6/pcm.c
+++ b/sound/usb/line6/pcm.c
@@ -226,9 +226,8 @@ int snd_line6_trigger(struct snd_pcm_substream *substream, int cmd)
 {
         struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
         struct snd_pcm_substream *s;
-        int err;
+        int err = 0;
 
-        spin_lock(&line6pcm->lock_trigger);
         clear_bit(LINE6_INDEX_PREPARED, &line6pcm->flags);
 
         snd_pcm_group_for_each_entry(s, substream) {
@@ -237,32 +236,23 @@ int snd_line6_trigger(struct snd_pcm_substream *substream, int cmd)
                 switch (s->stream) {
                 case SNDRV_PCM_STREAM_PLAYBACK:
                         err = snd_line6_playback_trigger(line6pcm, cmd);
-
-                        if (err < 0) {
-                                spin_unlock(&line6pcm->lock_trigger);
-                                return err;
-                        }
-
                         break;
 
                 case SNDRV_PCM_STREAM_CAPTURE:
                         err = snd_line6_capture_trigger(line6pcm, cmd);
-
-                        if (err < 0) {
-                                spin_unlock(&line6pcm->lock_trigger);
-                                return err;
-                        }
-
                         break;
 
                 default:
                         dev_err(line6pcm->line6->ifcdev,
                                 "Unknown stream direction %d\n", s->stream);
+                        err = -EINVAL;
+                        break;
                 }
+                if (err < 0)
+                        break;
         }
 
-        spin_unlock(&line6pcm->lock_trigger);
-        return 0;
+        return err;
 }
 
 /* control info callback */
@@ -427,7 +417,6 @@ int line6_init_pcm(struct usb_line6 *line6,
 
         spin_lock_init(&line6pcm->lock_audio_out);
         spin_lock_init(&line6pcm->lock_audio_in);
-        spin_lock_init(&line6pcm->lock_trigger);
         line6pcm->impulse_period = LINE6_IMPULSE_DEFAULT_PERIOD;
 
         line6->line6pcm = line6pcm;
diff --git a/sound/usb/line6/pcm.h b/sound/usb/line6/pcm.h
index c742b33666eb..a84753ee0fa2 100644
--- a/sound/usb/line6/pcm.h
+++ b/sound/usb/line6/pcm.h
@@ -308,11 +308,6 @@ struct snd_line6_pcm {
         spinlock_t lock_audio_in;
 
         /**
-                 Spin lock to protect trigger.
-        */
-        spinlock_t lock_trigger;
-
-        /**
                  PCM playback volume (left and right).
         */
         int volume_playback[2];