ALSA: fireworks: change the range of critical section for stream data in PCM.hw_free callback

The operation of duplex streams should be in critical section.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/firewire/fireworks/fireworks_pcm.c

@@ -247,14 +247,15 @@ static int pcm_hw_free(struct snd_pcm_substream *substream)
 {
 	struct snd_efw *efw = substream->private_data;
 
-	if (substream->runtime->status->state != SNDRV_PCM_STATE_OPEN) {
 	mutex_lock(&efw->mutex);
+
+	if (substream->runtime->status->state != SNDRV_PCM_STATE_OPEN)
 		--efw->substreams_counter;
-		mutex_unlock(&efw->mutex);
-	}
 
 	snd_efw_stream_stop_duplex(efw);
 
+	mutex_unlock(&efw->mutex);
+
 	return snd_pcm_lib_free_vmalloc_buffer(substream);
 }