ALSA: dice: Change the way to start stream

Streaming functionality can start streams when rate is given but currently
some codes are in PCM functionality.

This commit changes the way to start stream and add some arrangement
to make it easy to understand the way.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/firewire/dice/dice-pcm.c

@@ -169,65 +169,11 @@ static int playback_hw_params(struct snd_pcm_substream *substream,
 			      struct snd_pcm_hw_params *hw_params)
 {
 	struct snd_dice *dice = substream->private_data;
-	unsigned int mode, rate, channels, i;
-	int err;
-
-	mutex_lock(&dice->mutex);
-	snd_dice_stream_stop(dice);
-	mutex_unlock(&dice->mutex);
-
-	err = snd_pcm_lib_alloc_vmalloc_buffer(substream,
-					       params_buffer_bytes(hw_params));
-	if (err < 0)
-		return err;
-
-	rate = params_rate(hw_params);
-	err = snd_dice_transaction_set_rate(dice, rate);
-	if (err < 0)
-		return err;
-
-	if (snd_dice_stream_get_rate_mode(dice, rate, &mode) < 0)
-		return err;
-
-	/*
-	 * At 176.4/192.0 kHz, Dice has a quirk to transfer two PCM frames in
-	 * one data block of AMDTP packet. Thus sampling transfer frequency is
-	 * a half of PCM sampling frequency, i.e. PCM frames at 192.0 kHz are
-	 * transferred on AMDTP packets at 96 kHz. Two successive samples of a
-	 * channel are stored consecutively in the packet. This quirk is called
-	 * as 'Dual Wire'.
-	 * For this quirk, blocking mode is required and PCM buffer size should
-	 * be aligned to SYT_INTERVAL.
-	 */
-	channels = params_channels(hw_params);
-	if (mode > 1) {
-		if (channels > AMDTP_MAX_CHANNELS_FOR_PCM / 2) {
-			err = -ENOSYS;
-			return err;
-		}
-
-		rate /= 2;
-		channels *= 2;
-		dice->rx_stream.double_pcm_frames = true;
-	} else {
-		dice->rx_stream.double_pcm_frames = false;
-	}
-
-	amdtp_stream_set_parameters(&dice->rx_stream, rate, channels,
-				    dice->rx_midi_ports[mode]);
-	if (mode > 1) {
-		channels /= 2;
-
-		for (i = 0; i < channels; i++) {
-			dice->rx_stream.pcm_positions[i] = i * 2;
-			dice->rx_stream.pcm_positions[i + channels] = i * 2 + 1;
-		}
-	}
-
 	amdtp_stream_set_pcm_format(&dice->rx_stream,
 				    params_format(hw_params));
 
-	return 0;
+	return snd_pcm_lib_alloc_vmalloc_buffer(substream,
+						params_buffer_bytes(hw_params));
 }
 
 static int playback_hw_free(struct snd_pcm_substream *substream)
@@ -247,21 +193,12 @@ static int playback_prepare(struct snd_pcm_substream *substream)
 	int err;
 
 	mutex_lock(&dice->mutex);
-
-	if (amdtp_streaming_error(&dice->rx_stream))
-		snd_dice_stream_stop_packets(dice);
-
-	err = snd_dice_stream_start(dice);
-	if (err < 0) {
+	err = snd_dice_stream_start(dice, substream->runtime->rate);
 	mutex_unlock(&dice->mutex);
-		return err;
-	}
-
-	mutex_unlock(&dice->mutex);
-
+	if (err >= 0)
 		amdtp_stream_pcm_prepare(&dice->rx_stream);
 
-	return 0;
+	return err;
 }
 
 static int playback_trigger(struct snd_pcm_substream *substream, int cmd)

sound/firewire/dice/dice-stream.c

@@ -9,6 +9,8 @@
 
 #include "dice.h"
 
+#define	CALLBACK_TIMEOUT	200
+
 const unsigned int snd_dice_rates[SND_DICE_RATES_COUNT] = {
 	/* mode 0 */
 	[0] =  32000,
@@ -39,83 +41,162 @@ int snd_dice_stream_get_rate_mode(struct snd_dice *dice, unsigned int rate,
 	return -EINVAL;
 }
 
-int snd_dice_stream_start_packets(struct snd_dice *dice)
+static void release_resources(struct snd_dice *dice)
 {
-	int err;
-
-	if (amdtp_stream_running(&dice->rx_stream))
-		return 0;
-
-	err = amdtp_stream_start(&dice->rx_stream, dice->rx_resources.channel,
-				 fw_parent_device(dice->unit)->max_speed);
-	if (err < 0)
-		return err;
+	unsigned int channel;
 
-	err = snd_dice_transaction_set_enable(dice);
-	if (err < 0) {
-		amdtp_stream_stop(&dice->rx_stream);
-		return err;
-	}
+	/* Reset channel number */
+	channel = cpu_to_be32((u32)-1);
+	snd_dice_transaction_write_rx(dice, RX_ISOCHRONOUS, &channel, 4);
 
-	return 0;
+	fw_iso_resources_free(&dice->rx_resources);
 }
 
-int snd_dice_stream_start(struct snd_dice *dice)
+static int keep_resources(struct snd_dice *dice, unsigned int max_payload_bytes)
 {
-	__be32 channel;
+	unsigned int channel;
 	int err;
 
-	if (!dice->rx_resources.allocated) {
-		err = fw_iso_resources_allocate(&dice->rx_resources,
-				amdtp_stream_get_max_payload(&dice->rx_stream),
+	err = fw_iso_resources_allocate(&dice->rx_resources, max_payload_bytes,
 				fw_parent_device(dice->unit)->max_speed);
 	if (err < 0)
-			goto error;
+		goto end;
 
+	/* Set channel number */
 	channel = cpu_to_be32(dice->rx_resources.channel);
-		err = snd_dice_transaction_write_tx(dice, RX_ISOCHRONOUS,
+	err = snd_dice_transaction_write_rx(dice, RX_ISOCHRONOUS,
 					    &channel, 4);
 	if (err < 0)
-			goto err_resources;
-	}
-
-	err = snd_dice_stream_start_packets(dice);
-	if (err < 0)
-		goto err_rx_channel;
-
-	return 0;
-
-err_rx_channel:
-	channel = cpu_to_be32((u32)-1);
-	snd_dice_transaction_write_rx(dice, RX_ISOCHRONOUS, &channel, 4);
-err_resources:
-	fw_iso_resources_free(&dice->rx_resources);
-error:
+		release_resources(dice);
+end:
 	return err;
 }
 
-void snd_dice_stream_stop_packets(struct snd_dice *dice)
+static void stop_stream(struct snd_dice *dice)
 {
 	if (!amdtp_stream_running(&dice->rx_stream))
 		return;
 
-	snd_dice_transaction_clear_enable(dice);
+	amdtp_stream_pcm_abort(&dice->rx_stream);
 	amdtp_stream_stop(&dice->rx_stream);
+	release_resources(dice);
 }
 
-void snd_dice_stream_stop(struct snd_dice *dice)
+static int start_stream(struct snd_dice *dice, unsigned int rate)
 {
-	__be32 channel;
+	unsigned int i, mode, pcm_chs, midi_ports;
+	int err;
 
-	snd_dice_stream_stop_packets(dice);
+	err = snd_dice_stream_get_rate_mode(dice, rate, &mode);
+	if (err < 0)
+		goto end;
 
-	if (!dice->rx_resources.allocated)
-		return;
+	/*
+	 * At 176.4/192.0 kHz, Dice has a quirk to transfer two PCM frames in
+	 * one data block of AMDTP packet. Thus sampling transfer frequency is
+	 * a half of PCM sampling frequency, i.e. PCM frames at 192.0 kHz are
+	 * transferred on AMDTP packets at 96 kHz. Two successive samples of a
+	 * channel are stored consecutively in the packet. This quirk is called
+	 * as 'Dual Wire'.
+	 * For this quirk, blocking mode is required and PCM buffer size should
+	 * be aligned to SYT_INTERVAL.
+	 */
+	pcm_chs = dice->rx_channels[mode];
+	midi_ports = dice->rx_midi_ports[mode];
+	if (mode > 1) {
+		rate /= 2;
+		pcm_chs *= 2;
+		dice->rx_stream.double_pcm_frames = true;
+	} else {
+		dice->rx_stream.double_pcm_frames = false;
+	}
 
-	channel = cpu_to_be32((u32)-1);
-	snd_dice_transaction_write_rx(dice, RX_ISOCHRONOUS, &channel, 4);
+	amdtp_stream_set_parameters(&dice->rx_stream, rate,
+				    pcm_chs, midi_ports);
+	if (mode > 1) {
+		pcm_chs /= 2;
 
-	fw_iso_resources_free(&dice->rx_resources);
+		for (i = 0; i < pcm_chs; i++) {
+			dice->rx_stream.pcm_positions[i] = i * 2;
+			dice->rx_stream.pcm_positions[i + pcm_chs] = i * 2 + 1;
+		}
+	}
+
+	err = keep_resources(dice,
+			     amdtp_stream_get_max_payload(&dice->rx_stream));
+	if (err < 0) {
+		dev_err(&dice->unit->device,
+			"fail to keep isochronous resources\n");
+		goto end;
+	}
+
+	err = amdtp_stream_start(&dice->rx_stream, dice->rx_resources.channel,
+				 fw_parent_device(dice->unit)->max_speed);
+	if (err < 0)
+		release_resources(dice);
+end:
+	return err;
+}
+
+int snd_dice_stream_start(struct snd_dice *dice, unsigned int rate)
+{
+	unsigned int curr_rate;
+	int err;
+
+	/* Some packet queueing errors. */
+	if (amdtp_streaming_error(&dice->rx_stream))
+		stop_stream(dice);
+
+	/* Stop stream if rate is different. */
+	err = snd_dice_transaction_get_rate(dice, &curr_rate);
+	if (err < 0) {
+		dev_err(&dice->unit->device,
+			"fail to get sampling rate\n");
+		goto end;
+	}
+	if (rate != curr_rate)
+		stop_stream(dice);
+
+	if (!amdtp_stream_running(&dice->rx_stream)) {
+		snd_dice_transaction_clear_enable(dice);
+
+		err = snd_dice_transaction_set_rate(dice, rate);
+		if (err < 0) {
+			dev_err(&dice->unit->device,
+				"fail to set sampling rate\n");
+			goto end;
+		}
+
+		/* Start stream. */
+		err = start_stream(dice, rate);
+		if (err < 0) {
+			dev_err(&dice->unit->device,
+				"fail to start AMDTP stream\n");
+			goto end;
+		}
+		err = snd_dice_transaction_set_enable(dice);
+		if (err < 0) {
+			dev_err(&dice->unit->device,
+				"fail to enable interface\n");
+			stop_stream(dice);
+			goto end;
+		}
+
+		if (!amdtp_stream_wait_callback(&dice->rx_stream,
+						CALLBACK_TIMEOUT)) {
+			snd_dice_transaction_clear_enable(dice);
+			stop_stream(dice);
+			err = -ETIMEDOUT;
+		}
+	}
+end:
+	return err;
+}
+
+void snd_dice_stream_stop(struct snd_dice *dice)
+{
+	snd_dice_transaction_clear_enable(dice);
+	stop_stream(dice);
 }
 
 int snd_dice_stream_init(struct snd_dice *dice)
@@ -145,8 +226,8 @@ int snd_dice_stream_init(struct snd_dice *dice)
 
 void snd_dice_stream_destroy(struct snd_dice *dice)
 {
-	amdtp_stream_pcm_abort(&dice->rx_stream);
-	snd_dice_stream_stop(dice);
+	snd_dice_transaction_clear_enable(dice);
+	stop_stream(dice);
 	amdtp_stream_destroy(&dice->rx_stream);
 	fw_iso_resources_destroy(&dice->rx_resources);
 }
@@ -163,8 +244,8 @@ void snd_dice_stream_update(struct snd_dice *dice)
 	 */
 	dice->global_enabled = false;
 
-	amdtp_stream_pcm_abort(&dice->rx_stream);
-	snd_dice_stream_stop_packets(dice);
+	stop_stream(dice);
+
 	fw_iso_resources_update(&dice->rx_resources);
 }
 

sound/firewire/dice/dice.c

@@ -304,12 +304,8 @@ static void dice_remove(struct fw_unit *unit)
 
 	snd_card_disconnect(dice->card);
 
-	mutex_lock(&dice->mutex);
-
 	snd_dice_stream_destroy(dice);
 
-	mutex_unlock(&dice->mutex);
-
 	snd_card_free_when_closed(dice->card);
 }
 

sound/firewire/dice/dice.h

@@ -160,9 +160,7 @@ extern const unsigned int snd_dice_rates[SND_DICE_RATES_COUNT];
 int snd_dice_stream_get_rate_mode(struct snd_dice *dice,
 				  unsigned int rate, unsigned int *mode);
 
-int snd_dice_stream_start_packets(struct snd_dice *dice);
-int snd_dice_stream_start(struct snd_dice *dice);
-void snd_dice_stream_stop_packets(struct snd_dice *dice);
+int snd_dice_stream_start(struct snd_dice *dice, unsigned int rate);
 void snd_dice_stream_stop(struct snd_dice *dice);
 int snd_dice_stream_init(struct snd_dice *dice);
 void snd_dice_stream_destroy(struct snd_dice *dice);