ALSA: usb-audio: Switch back to non-latency mode at a later point

[linux-2.6-microblaze.git] / sound / usb / pcm.c

diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index 95ec8ee..57b046e 100644 (file)
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -581,6 +581,12 @@ static int snd_usb_hw_free(struct snd_pcm_substream *substream)
        return 0;
 }
 
+/* free-wheeling mode? (e.g. dmix) */
+static int in_free_wheeling_mode(struct snd_pcm_runtime *runtime)
+{
+       return runtime->stop_threshold > runtime->buffer_size;
+}
+
 /* check whether early start is needed for playback stream */
 static int lowlatency_playback_available(struct snd_pcm_runtime *runtime,
                                         struct snd_usb_substream *subs)
@@ -592,8 +598,7 @@ static int lowlatency_playback_available(struct snd_pcm_runtime *runtime,
        /* disabled via module option? */
        if (!chip->lowlatency)
                return false;
-       /* free-wheeling mode? (e.g. dmix) */
-       if (runtime->stop_threshold > runtime->buffer_size)
+       if (in_free_wheeling_mode(runtime))
                return false;
        /* implicit feedback mode has own operation mode */
        if (snd_usb_endpoint_implicit_feedback_sink(subs->data_endpoint))
@@ -1552,6 +1557,8 @@ static int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substrea
                                              subs);
                if (subs->lowlatency_playback &&
                    cmd == SNDRV_PCM_TRIGGER_START) {
+                       if (in_free_wheeling_mode(substream->runtime))
+                               subs->lowlatency_playback = false;
                        err = start_endpoints(subs);
                        if (err < 0) {
                                snd_usb_endpoint_set_callback(subs->data_endpoint,