ALSA: firewire-lib: add an argument for Dice's dual wire mode

In IEC 61883-6, one data block represents one event. In ALSA, the event is
one PCM frame. Therefore, when processing one data block, current
implementation counts one PCM frame.

On the other hand, Dice platform has a quirk called as 'dual wire' at
higher sampling rate. In detail, see comment of commit 6eb6c81eee
("ALSA: dice: Split stream functionality into a file").

Currently, to handle this quirk, AMDTP stream structure has a
'double_pcm_frames' member. When this is enabled, two PCM frames are
counted. Each driver set this flag by accessing the structure member
directly.

In future commit, some members related to AM824 data block will be moved
to specific structure, to separate packet streaming layer and data block
processing layer. The access will be limited by opaque pointer.

For this reason, this commit adds an argument into
amdtp_stream_set_parameter() to set the flag.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/firewire/amdtp.c

@@ -193,6 +193,7 @@ EXPORT_SYMBOL(amdtp_stream_add_pcm_hw_constraints);
  * @pcm_channels: the number of PCM samples in each data block, to be encoded
  *                as AM824 multi-bit linear audio
  * @midi_ports: the number of MIDI ports (i.e., MPX-MIDI Data Channels)
+ * @double_pcm_frames: one data block transfers two PCM frames
  *
  * The parameters must be set before the stream is started, and must not be
  * changed while the stream is running.
@@ -200,7 +201,8 @@ EXPORT_SYMBOL(amdtp_stream_add_pcm_hw_constraints);
 int amdtp_stream_set_parameters(struct amdtp_stream *s,
 				unsigned int rate,
 				unsigned int pcm_channels,
-				unsigned int midi_ports)
+				unsigned int midi_ports,
+				bool double_pcm_frames)
 {
 	unsigned int i, sfc, midi_channels;
 

sound/firewire/amdtp.h

@@ -177,7 +177,8 @@ void amdtp_stream_destroy(struct amdtp_stream *s);
 int amdtp_stream_set_parameters(struct amdtp_stream *s,
 				unsigned int rate,
 				unsigned int pcm_channels,
-				unsigned int midi_ports);
+				unsigned int midi_ports,
+				bool double_pcm_frames);
 unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
 
 int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed);

sound/firewire/bebob/bebob_stream.c

@@ -428,14 +428,16 @@ make_both_connections(struct snd_bebob *bebob, unsigned int rate)
 	pcm_channels = bebob->tx_stream_formations[index].pcm;
 	midi_channels = bebob->tx_stream_formations[index].midi;
 	err = amdtp_stream_set_parameters(&bebob->tx_stream, rate,
-					  pcm_channels, midi_channels * 8);
+					  pcm_channels, midi_channels * 8,
+					  false);
 	if (err < 0)
 		goto end;
 
 	pcm_channels = bebob->rx_stream_formations[index].pcm;
 	midi_channels = bebob->rx_stream_formations[index].midi;
 	err = amdtp_stream_set_parameters(&bebob->rx_stream, rate,
-					  pcm_channels, midi_channels * 8);
+					  pcm_channels, midi_channels * 8,
+					  false);
 	if (err < 0)
 		goto end;
 

sound/firewire/dice/dice-stream.c

@@ -100,6 +100,7 @@ static int start_stream(struct snd_dice *dice, struct amdtp_stream *stream,
 {
 	struct fw_iso_resources *resources;
 	unsigned int i, mode, pcm_chs, midi_ports;
+	bool double_pcm_frames;
 	int err;
 
 	err = snd_dice_stream_get_rate_mode(dice, rate, &mode);
@@ -125,19 +126,18 @@ static int start_stream(struct snd_dice *dice, struct amdtp_stream *stream,
 	 * For this quirk, blocking mode is required and PCM buffer size should
 	 * be aligned to SYT_INTERVAL.
 	 */
-	if (mode > 1) {
+	double_pcm_frames = mode > 1;
+	if (double_pcm_frames) {
 		rate /= 2;
 		pcm_chs *= 2;
-		stream->double_pcm_frames = true;
-	} else {
-		stream->double_pcm_frames = false;
 	}
 
-	err = amdtp_stream_set_parameters(stream, rate, pcm_chs, midi_ports);
+	err = amdtp_stream_set_parameters(stream, rate, pcm_chs, midi_ports,
+					  false);
 	if (err < 0)
 		goto end;
 
-	if (mode > 1) {
+	if (double_pcm_frames) {
 		pcm_chs /= 2;
 
 		for (i = 0; i < pcm_chs; i++) {

sound/firewire/fireworks/fireworks_stream.c

@@ -74,7 +74,7 @@ start_stream(struct snd_efw *efw, struct amdtp_stream *stream,
 	}
 
 	err = amdtp_stream_set_parameters(stream, sampling_rate,
-					  pcm_channels, midi_ports);
+					  pcm_channels, midi_ports, false);
 	if (err < 0)
 		goto end;
 

sound/firewire/oxfw/oxfw-stream.c

@@ -156,7 +156,7 @@ static int start_stream(struct snd_oxfw *oxfw, struct amdtp_stream *stream,
 		goto end;
 	}
 	err = amdtp_stream_set_parameters(stream, rate,
-					  pcm_channels, midi_ports);
+					  pcm_channels, midi_ports, false);
 	if (err < 0)
 		goto end;