[alsa-devel] [PATCH 09/13] dice: Change the way to start stream

Takashi Sakamoto o-takashi at sakamocchi.jp
Sun May 18 15:36:34 CEST 2014


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 at sakamocchi.jp>
---
 sound/firewire/dice/dice.c        |  10 +-
 sound/firewire/dice/dice.h        |   4 +-
 sound/firewire/dice/dice_pcm.c    |  67 ++------------
 sound/firewire/dice/dice_stream.c | 190 +++++++++++++++++++++++++++-----------
 4 files changed, 145 insertions(+), 126 deletions(-)

diff --git a/sound/firewire/dice/dice.c b/sound/firewire/dice/dice.c
index 88446a0..33c5253 100644
--- a/sound/firewire/dice/dice.c
+++ b/sound/firewire/dice/dice.c
@@ -303,12 +303,8 @@ 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);
 }
 
@@ -324,11 +320,7 @@ static void dice_bus_reset(struct fw_unit *unit)
 	}
 	dice->global_enabled = false;
 
-	mutex_lock(&dice->mutex);
-
-	snd_dice_stream_stop_packets(dice);
-
-	mutex_unlock(&dice->mutex);
+	snd_dice_stream_update(dice);
 }
 
 #define DICE_INTERFACE	0x000001
diff --git a/sound/firewire/dice/dice.h b/sound/firewire/dice/dice.h
index 969189a..8be530f 100644
--- a/sound/firewire/dice/dice.h
+++ b/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);
diff --git a/sound/firewire/dice/dice_pcm.c b/sound/firewire/dice/dice_pcm.c
index 6473676..79958e5 100644
--- a/sound/firewire/dice/dice_pcm.c
+++ b/sound/firewire/dice/dice_pcm.c
@@ -169,63 +169,19 @@ 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 rates above 96 kHz, pretend that the stream runs at half the
-	 * actual sample rate with twice the number of channels; two samples
-	 * of a channel are stored consecutively in the packet. Requires
-	 * blocking mode 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;
-		}
-
-		for (i = 0; i < channels; i++) {
-			dice->rx_stream.pcm_positions[i * 2] = i;
-			dice->rx_stream.pcm_positions[i * 2 + 1] = i + channels;
-		}
-
-		rate /= 2;
-		channels *= 2;
-	}
-
-	amdtp_stream_set_parameters(&dice->rx_stream, rate, channels,
-				    dice->rx_midi_ports[mode]);
 	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)
 {
 	struct snd_dice *dice = substream->private_data;
 
-	mutex_lock(&dice->mutex);
 	snd_dice_stream_stop(dice);
-	mutex_unlock(&dice->mutex);
 
 	return snd_pcm_lib_free_vmalloc_buffer(substream);
 }
@@ -235,22 +191,11 @@ static int playback_prepare(struct snd_pcm_substream *substream)
 	struct snd_dice *dice = substream->private_data;
 	int err;
 
-	mutex_lock(&dice->mutex);
+	err = snd_dice_stream_start(dice, substream->runtime->rate);
+	if (err >= 0)
+		amdtp_stream_pcm_prepare(&dice->rx_stream);
 
-	if (amdtp_streaming_error(&dice->rx_stream))
-		snd_dice_stream_stop_packets(dice);
-
-	err = snd_dice_stream_start(dice);
-	if (err < 0) {
-		mutex_unlock(&dice->mutex);
-		return err;
-	}
-
-	mutex_unlock(&dice->mutex);
-
-	amdtp_stream_pcm_prepare(&dice->rx_stream);
-
-	return 0;
+	return err;
 }
 
 static int playback_trigger(struct snd_pcm_substream *substream, int cmd)
diff --git a/sound/firewire/dice/dice_stream.c b/sound/firewire/dice/dice_stream.c
index ba8fe8d..ed5c961 100644
--- a/sound/firewire/dice/dice_stream.c
+++ b/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,
@@ -38,82 +40,157 @@ 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;
+	unsigned int channel;
 
-	if (amdtp_stream_running(&dice->rx_stream))
-		return 0;
+	/* Reset channel number */
+	channel = cpu_to_be32((u32)-1);
+	snd_dice_transaction_write_rx(dice, RX_ISOCHRONOUS, &channel, 4);
 
-	err = amdtp_stream_start(&dice->rx_stream, dice->rx_resources.channel,
-				 fw_parent_device(dice->unit)->max_speed);
+	fw_iso_resources_free(&dice->rx_resources);
+}
+
+static int keep_resources(struct snd_dice *dice, unsigned int max_payload_bytes)
+{
+	unsigned int channel;
+	int err;
+
+	err = fw_iso_resources_allocate(&dice->rx_resources, max_payload_bytes,
+			fw_parent_device(dice->unit)->max_speed);
 	if (err < 0)
-		return err;
+		goto end;
 
-	err = snd_dice_transaction_set_enable(dice);
-	if (err < 0) {
-		amdtp_stream_stop(&dice->rx_stream);
-		return err;
-	}
+	/* Set channel number */
+	channel = cpu_to_be32(dice->rx_resources.channel);
+	err = snd_dice_transaction_write_rx(dice, RX_ISOCHRONOUS,
+					    &channel, 4);
+	if (err < 0)
+		release_resources(dice);
+end:
+	return err;
+}
 
-	return 0;
+static void stop_stream(struct snd_dice *dice)
+{
+	amdtp_stream_pcm_abort(&dice->rx_stream);
+	amdtp_stream_stop(&dice->rx_stream);
+	release_resources(dice);
 }
 
-int snd_dice_stream_start(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;
 
-	if (!dice->rx_resources.allocated) {
-		err = fw_iso_resources_allocate(&dice->rx_resources,
-				amdtp_stream_get_max_payload(&dice->rx_stream),
-				fw_parent_device(dice->unit)->max_speed);
-		if (err < 0)
-			goto error;
-
-		channel = cpu_to_be32(dice->rx_resources.channel);
-		err = snd_dice_transaction_write_tx(dice, TX_ISOCHRONOUS,
-						    &channel, 4);
-		if (err < 0)
-			goto err_resources;
+	err = snd_dice_stream_get_rate_mode(dice, rate, &mode);
+	if (err < 0)
+		goto end;
+
+	/*
+	 * At rates above 96 kHz, pretend that the stream runs at half the
+	 * actual sample rate with twice the number of channels; two samples
+	 * of a channel are stored consecutively in the packet. Requires
+	 * blocking mode 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 >= 2) {
+		for (i = 0; i < pcm_chs; i++) {
+			dice->rx_stream.pcm_positions[i * 2] = i;
+			dice->rx_stream.pcm_positions[i * 2 + 1] = i + pcm_chs;
+		}
+
+		rate /= 2;
+		pcm_chs *= 2;
 	}
 
-	err = snd_dice_stream_start_packets(dice);
-	if (err < 0)
-		goto err_rx_channel;
+	amdtp_stream_set_parameters(&dice->rx_stream, rate,
+				    pcm_chs, midi_ports);
 
-	return 0;
+	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_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:
+	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;
 }
 
-void snd_dice_stream_stop_packets(struct snd_dice *dice)
+int snd_dice_stream_start(struct snd_dice *dice, unsigned int rate)
 {
-	if (amdtp_stream_running(&dice->rx_stream)) {
+	unsigned int curr_rate;
+	int err;
+
+	mutex_lock(&dice->mutex);
+
+	/* 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);
-		amdtp_stream_stop(&dice->rx_stream);
+
+		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:
+	mutex_unlock(&dice->mutex);
+	return err;
 }
 
 void snd_dice_stream_stop(struct snd_dice *dice)
 {
-	__be32 channel;
-
-	snd_dice_stream_stop_packets(dice);
+	mutex_lock(&dice->mutex);
 
-	if (!dice->rx_resources.allocated)
-		return;
+	snd_dice_transaction_clear_enable(dice);
+	stop_stream(dice);
 
-	channel = cpu_to_be32((u32)-1);
-	snd_dice_transaction_write_rx(dice, RX_ISOCHRONOUS, &channel, 4);
-
-	fw_iso_resources_free(&dice->rx_resources);
+	mutex_unlock(&dice->mutex);
 }
 
 int snd_dice_stream_init(struct snd_dice *dice)
@@ -143,10 +220,14 @@ error:
 
 void snd_dice_stream_destroy(struct snd_dice *dice)
 {
-	amdtp_stream_pcm_abort(&dice->rx_stream);
-	snd_dice_stream_stop(dice);
+	mutex_lock(&dice->mutex);
+
+	snd_dice_transaction_clear_enable(dice);
+	stop_stream(dice);
 	amdtp_stream_destroy(&dice->rx_stream);
 	fw_iso_resources_destroy(&dice->rx_resources);
+
+	mutex_unlock(&dice->mutex);
 }
 
 void snd_dice_stream_update(struct snd_dice *dice)
@@ -159,9 +240,12 @@ void snd_dice_stream_update(struct snd_dice *dice)
 	 * to stop so that the application can restart them in an orderly
 	 * manner.
 	 */
-	amdtp_stream_pcm_abort(&dice->rx_stream);
-	snd_dice_stream_stop_packets(dice);
+	mutex_lock(&dice->mutex);
+
+	stop_stream(dice);
 	fw_iso_resources_update(&dice->rx_resources);
+
+	mutex_unlock(&dice->mutex);
 }
 
 static void dice_lock_changed(struct snd_dice *dice)
-- 
1.8.3.2



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