ALSA: fireworks: share PCM buffer size for both direction

This commit allows ALSA fireworks driver to share PCM buffer size for
both capture and playback PCM substream. When AMDTP domain starts for
one of the PCM substream, buffer size of the PCM substream is stores
to AMDTP domain structure. Some AMDTP streams have already run with the
buffer size when another PCM substream starts, therefore the PCM
substream has a constraint to its buffer size.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20191017155424.885-4-o-takashi@sakamocchi.jpSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/firewire/fireworks/fireworks.h

@@ -208,7 +208,8 @@ int snd_efw_command_set_sampling_rate(struct snd_efw *efw, unsigned int rate);
 
 int snd_efw_stream_init_duplex(struct snd_efw *efw);
 int snd_efw_stream_reserve_duplex(struct snd_efw *efw, unsigned int rate,
-				  unsigned int frames_per_period);
+				  unsigned int frames_per_period,
+				  unsigned int frames_per_buffer);
 int snd_efw_stream_start_duplex(struct snd_efw *efw);
 void snd_efw_stream_stop_duplex(struct snd_efw *efw);
 void snd_efw_stream_update_duplex(struct snd_efw *efw);

sound/firewire/fireworks/fireworks_midi.c

@@ -17,7 +17,7 @@ static int midi_open(struct snd_rawmidi_substream *substream)
 		goto end;
 
 	mutex_lock(&efw->mutex);
-	err = snd_efw_stream_reserve_duplex(efw, 0, 0);
+	err = snd_efw_stream_reserve_duplex(efw, 0, 0, 0);
 	if (err >= 0) {
 		++efw->substreams_counter;
 		err = snd_efw_stream_start_duplex(efw);

sound/firewire/fireworks/fireworks_pcm.c

@@ -197,6 +197,7 @@ static int pcm_open(struct snd_pcm_substream *substream)
 	if ((clock_source != SND_EFW_CLOCK_SOURCE_INTERNAL) ||
 	    (efw->substreams_counter > 0 && d->events_per_period > 0)) {
 		unsigned int frames_per_period = d->events_per_period;
+		unsigned int frames_per_buffer = d->events_per_buffer;
 		unsigned int sampling_rate;
 
 		err = snd_efw_command_get_sampling_rate(efw, &sampling_rate);
@@ -215,6 +216,14 @@ static int pcm_open(struct snd_pcm_substream *substream)
 				mutex_unlock(&efw->mutex);
 				goto err_locked;
 			}
+
+			err = snd_pcm_hw_constraint_minmax(substream->runtime,
+					SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
+					frames_per_buffer, frames_per_buffer);
+			if (err < 0) {
+				mutex_unlock(&efw->mutex);
+				goto err_locked;
+			}
 		}
 	}
 
@@ -249,10 +258,11 @@ static int pcm_hw_params(struct snd_pcm_substream *substream,
 	if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN) {
 		unsigned int rate = params_rate(hw_params);
 		unsigned int frames_per_period = params_period_size(hw_params);
+		unsigned int frames_per_buffer = params_buffer_size(hw_params);
 
 		mutex_lock(&efw->mutex);
 		err = snd_efw_stream_reserve_duplex(efw, rate,
-						    frames_per_period);
+					frames_per_period, frames_per_buffer);
 		if (err >= 0)
 			++efw->substreams_counter;
 		mutex_unlock(&efw->mutex);

sound/firewire/fireworks/fireworks_stream.c

@@ -182,7 +182,8 @@ static int keep_resources(struct snd_efw *efw, struct amdtp_stream *stream,
 }
 
 int snd_efw_stream_reserve_duplex(struct snd_efw *efw, unsigned int rate,
-				  unsigned int frames_per_period)
+				  unsigned int frames_per_period,
+				  unsigned int frames_per_buffer)
 {
 	unsigned int curr_rate;
 	int err;
@@ -231,7 +232,7 @@ int snd_efw_stream_reserve_duplex(struct snd_efw *efw, unsigned int rate,
 		}
 
 		err = amdtp_domain_set_events_per_period(&efw->domain,
-							 frames_per_period, 0);
+					frames_per_period, frames_per_buffer);
 		if (err < 0) {
 			cmp_connection_release(&efw->in_conn);
 			cmp_connection_release(&efw->out_conn);