3 files changed, 15 insertions, 11 deletions

diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
index c41181202688..b896c5559524 100644
--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -799,7 +799,9 @@ int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
 /**
  * snd_usb_endpoint_start: start an snd_usb_endpoint
  *
- * @ep: the endpoint to start
+ * @ep:         the endpoint to start
+ * @can_sleep:  flag indicating whether the operation is executed in
+ *              non-atomic context
  *
  * A call to this function will increment the use count of the endpoint.
  * In case it is not already running, the URBs for this endpoint will be
@@ -809,7 +811,7 @@ int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
  *
  * Returns an error if the URB submission failed, 0 in all other cases.
  */
-int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
+int snd_usb_endpoint_start(struct snd_usb_endpoint *ep, int can_sleep)
 {
         int err;
         unsigned int i;
@@ -821,6 +823,11 @@ int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
         if (++ep->use_count != 1)
                 return 0;
 
+        /* just to be sure */
+        deactivate_urbs(ep, 0, can_sleep);
+        if (can_sleep)
+                wait_clear_urbs(ep);
+
         ep->active_mask = 0;
         ep->unlink_mask = 0;
         ep->phase = 0;
diff --git a/sound/usb/endpoint.h b/sound/usb/endpoint.h
index ee2723fb174f..a8e60c1408e5 100644
--- a/sound/usb/endpoint.h
+++ b/sound/usb/endpoint.h
@@ -13,7 +13,7 @@ int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
                                 struct audioformat *fmt,
                                 struct snd_usb_endpoint *sync_ep);
 
-int  snd_usb_endpoint_start(struct snd_usb_endpoint *ep);
+int  snd_usb_endpoint_start(struct snd_usb_endpoint *ep, int can_sleep);
 void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep,
                            int force, int can_sleep, int wait);
 int  snd_usb_endpoint_activate(struct snd_usb_endpoint *ep);
diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index 62ec808ed792..1546577ae458 100644
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -212,7 +212,7 @@ int snd_usb_init_pitch(struct snd_usb_audio *chip, int iface,
         }
 }
 
-static int start_endpoints(struct snd_usb_substream *subs)
+static int start_endpoints(struct snd_usb_substream *subs, int can_sleep)
 {
         int err;
 
@@ -225,7 +225,7 @@ static int start_endpoints(struct snd_usb_substream *subs)
                 snd_printdd(KERN_DEBUG "Starting data EP @%p\n", ep);
 
                 ep->data_subs = subs;
-                err = snd_usb_endpoint_start(ep);
+                err = snd_usb_endpoint_start(ep, can_sleep);
                 if (err < 0) {
                         clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags);
                         return err;
@@ -239,7 +239,7 @@ static int start_endpoints(struct snd_usb_substream *subs)
                 snd_printdd(KERN_DEBUG "Starting sync EP @%p\n", ep);
 
                 ep->sync_slave = subs->data_endpoint;
-                err = snd_usb_endpoint_start(ep);
+                err = snd_usb_endpoint_start(ep, can_sleep);
                 if (err < 0) {
                         clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags);
                         return err;
@@ -544,13 +544,10 @@ static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
         subs->last_frame_number = 0;
         runtime->delay = 0;
 
-        /* clear the pending deactivation on the target EPs */
-        deactivate_endpoints(subs);
-
         /* for playback, submit the URBs now; otherwise, the first hwptr_done
          * updates for all URBs would happen at the same time when starting */
         if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
-                return start_endpoints(subs);
+                return start_endpoints(subs, 1);
 
         return 0;
 }
@@ -1175,7 +1172,7 @@ static int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream
 
         switch (cmd) {
         case SNDRV_PCM_TRIGGER_START:
-                err = start_endpoints(subs);
+                err = start_endpoints(subs, 0);
                 if (err < 0)
                         return err;