ALSA: line6: Skip volume manipulation during silence copying

A minor optimization; while pausing, the driver just copies the zero
that doesn't need any volume changes.

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

1 files changed, 3 insertions, 2 deletions

diff --git a/sound/usb/line6/playback.c b/sound/usb/line6/playback.c
index cbcd97f5d629..3762a98026aa 100644
--- a/sound/usb/line6/playback.c
+++ b/sound/usb/line6/playback.c
@@ -234,13 +234,14 @@ static int submit_audio_out_urb(struct snd_line6_pcm *line6pcm)
                 line6pcm->out.pos += urb_frames;
                 if (line6pcm->out.pos >= runtime->buffer_size)
                         line6pcm->out.pos -= runtime->buffer_size;
+
+                change_volume(urb_out, line6pcm->volume_playback,
+                              bytes_per_frame);
         } else {
                 memset(urb_out->transfer_buffer, 0,
                        urb_out->transfer_buffer_length);
         }
 
-        change_volume(urb_out, line6pcm->volume_playback, bytes_per_frame);
-
         if (line6pcm->prev_fbuf != NULL) {
                 if (line6pcm->flags & LINE6_BITS_PCM_IMPULSE) {
                         create_impulse_test_signal(line6pcm, urb_out,