ALSA: oxfw: share PCM buffer size for both direction

This commit allows ALSA oxfw 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 <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Takashi Iwai <[e-mail]>

sound/firewire/oxfw/oxfw-midi.c

···
 
 	mutex_lock(&oxfw->mutex);
 
-	err = snd_oxfw_stream_reserve_duplex(oxfw, &oxfw->tx_stream, 0, 0, 0);
+	err = snd_oxfw_stream_reserve_duplex(oxfw, &oxfw->tx_stream, 0, 0, 0, 0);
 	if (err >= 0) {
 		++oxfw->substreams_count;
 		err = snd_oxfw_stream_start_duplex(oxfw);
···
 
 	mutex_lock(&oxfw->mutex);
 
-	err = snd_oxfw_stream_reserve_duplex(oxfw, &oxfw->rx_stream, 0, 0, 0);
+	err = snd_oxfw_stream_reserve_duplex(oxfw, &oxfw->rx_stream, 0, 0, 0, 0);
 	if (err >= 0) {
 		++oxfw->substreams_count;
 		err = snd_oxfw_stream_start_duplex(oxfw);

sound/firewire/oxfw/oxfw-pcm.c

···
 	// at current one.
 	if (oxfw->substreams_count > 0 && d->events_per_period > 0) {
 		unsigned int frames_per_period = d->events_per_period;
+		unsigned int frames_per_buffer = d->events_per_buffer;
 
 		err = limit_to_current_params(substream);
 		if (err < 0) {
···
 			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(&oxfw->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(&oxfw->mutex);
 				goto err_locked;
···
 		unsigned int rate = params_rate(hw_params);
 		unsigned int channels = params_channels(hw_params);
 		unsigned int frames_per_period = params_period_size(hw_params);
+		unsigned int frames_per_buffer = params_buffer_size(hw_params);
 
 		mutex_lock(&oxfw->mutex);
 		err = snd_oxfw_stream_reserve_duplex(oxfw, &oxfw->tx_stream,
-					rate, channels, frames_per_period);
+					rate, channels, frames_per_period,
+					frames_per_buffer);
 		if (err >= 0)
 			++oxfw->substreams_count;
 		mutex_unlock(&oxfw->mutex);
···
 		unsigned int rate = params_rate(hw_params);
 		unsigned int channels = params_channels(hw_params);
 		unsigned int frames_per_period = params_period_size(hw_params);
+		unsigned int frames_per_buffer = params_buffer_size(hw_params);
 
 		mutex_lock(&oxfw->mutex);
 		err = snd_oxfw_stream_reserve_duplex(oxfw, &oxfw->rx_stream,
-					rate, channels, frames_per_period);
+					rate, channels, frames_per_period,
+					frames_per_buffer);
 		if (err >= 0)
 			++oxfw->substreams_count;
 		mutex_unlock(&oxfw->mutex);

sound/firewire/oxfw/oxfw-stream.c

···
 int snd_oxfw_stream_reserve_duplex(struct snd_oxfw *oxfw,
 				   struct amdtp_stream *stream,
 				   unsigned int rate, unsigned int pcm_channels,
-				   unsigned int frames_per_period)
+				   unsigned int frames_per_period,
+				   unsigned int frames_per_buffer)
 {
 	struct snd_oxfw_stream_formation formation;
 	enum avc_general_plug_dir dir;
···
 		}
 
 		err = amdtp_domain_set_events_per_period(&oxfw->domain,
-							frames_per_period, 0);
+					frames_per_period, frames_per_buffer);
 		if (err < 0) {
 			cmp_connection_release(&oxfw->in_conn);
 			if (oxfw->has_output)

sound/firewire/oxfw/oxfw.h

···
 int snd_oxfw_stream_reserve_duplex(struct snd_oxfw *oxfw,
 				   struct amdtp_stream *stream,
 				   unsigned int rate, unsigned int pcm_channels,
-				   unsigned int frames_per_period);
+				   unsigned int frames_per_period,
+				   unsigned int frames_per_buffer);
 int snd_oxfw_stream_start_duplex(struct snd_oxfw *oxfw);
 void snd_oxfw_stream_stop_duplex(struct snd_oxfw *oxfw);
 void snd_oxfw_stream_destroy_duplex(struct snd_oxfw *oxfw);