1 files changed, 26 insertions, 8 deletions

diff --git a/sound/firewire/tascam/tascam-pcm.c b/sound/firewire/tascam/tascam-pcm.c
index cea26d5eff1a..6cd3a420fbdf 100644
--- a/sound/firewire/tascam/tascam-pcm.c
+++ b/sound/firewire/tascam/tascam-pcm.c
@@ -43,13 +43,13 @@ static int pcm_init_hw_params(struct snd_tscm *tscm,
 static int pcm_open(struct snd_pcm_substream *substream)
 {
 	struct snd_tscm *tscm = substream->private_data;
+	struct amdtp_domain *d = &tscm->domain;
 	enum snd_tscm_clock clock;
-	unsigned int rate;
 	int err;
 
 	err = snd_tscm_stream_lock_try(tscm);
 	if (err < 0)
-		goto end;
+		return err;
 
 	err = pcm_init_hw_params(tscm, substream);
 	if (err < 0)
@@ -59,19 +59,37 @@ static int pcm_open(struct snd_pcm_substream *substream)
 	if (err < 0)
 		goto err_locked;
 
-	if (clock != SND_TSCM_CLOCK_INTERNAL ||
-	    amdtp_stream_pcm_running(&tscm->rx_stream) ||
-	    amdtp_stream_pcm_running(&tscm->tx_stream)) {
+	mutex_lock(&tscm->mutex);
+
+	// When source of clock is not internal or any stream is reserved for
+	// transmission of PCM frames, the available sampling rate is limited
+	// at current one.
+	if (clock != SND_TSCM_CLOCK_INTERNAL || tscm->substreams_counter > 0) {
+		unsigned int frames_per_period = d->events_per_period;
+		unsigned int rate;
+
 		err = snd_tscm_stream_get_rate(tscm, &rate);
-		if (err < 0)
+		if (err < 0) {
+			mutex_unlock(&tscm->mutex);
 			goto err_locked;
+		}
 		substream->runtime->hw.rate_min = rate;
 		substream->runtime->hw.rate_max = rate;
+
+		err = snd_pcm_hw_constraint_minmax(substream->runtime,
+					SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
+					frames_per_period, frames_per_period);
+		if (err < 0) {
+			mutex_unlock(&tscm->mutex);
+			goto err_locked;
+		}
 	}
 
+	mutex_unlock(&tscm->mutex);
+
 	snd_pcm_set_sync(substream);
-end:
-	return err;
+
+	return 0;
 err_locked:
 	snd_tscm_stream_lock_release(tscm);
 	return err;