Commit 6abce9e6 authored by Clemens Ladisch's avatar Clemens Ladisch
Browse files

ALSA: dice: optimize bus reset handling 



After a bus reset, do not stop the stream completely to avoid having to
reconfigure the device when restarting the stream.

Signed-off-by: default avatarClemens Ladisch <clemens@ladisch.de>
parent 82fbb4f7

sound/firewire/dice.c

+93 −55
Original line number Diff line number Diff line
@@ -559,24 +559,92 @@ static int dice_close(struct snd_pcm_substream *substream) 
	return 0;

}



static void dice_stop_stream(struct dice *dice)

static int dice_stream_start_packets(struct dice *dice)

{

	__be32 channel;

	int err;



	if (dice->stream_running) {

		dice_enable_clear(dice);

	if (dice->stream_running)

		return 0;



	err = amdtp_out_stream_start(&dice->stream, dice->resources.channel,

				     fw_parent_device(dice->unit)->max_speed);

	if (err < 0)

		return err;



	err = dice_enable_set(dice);

	if (err < 0) {

		amdtp_out_stream_stop(&dice->stream);

		return err;

	}



		channel = cpu_to_be32((u32)-1);

		snd_fw_transaction(dice->unit, TCODE_WRITE_QUADLET_REQUEST,

	dice->stream_running = true;



	return 0;

}



static int dice_stream_start(struct dice *dice)

{

	__be32 channel;

	int err;



	if (!dice->resources.allocated) {

		err = fw_iso_resources_allocate(&dice->resources,

				amdtp_out_stream_get_max_payload(&dice->stream),

				fw_parent_device(dice->unit)->max_speed);

		if (err < 0)

			goto error;



		channel = cpu_to_be32(dice->resources.channel);

		err = snd_fw_transaction(dice->unit,

					 TCODE_WRITE_QUADLET_REQUEST,

					 rx_address(dice, RX_ISOCHRONOUS),

					 &channel, 4);

		if (err < 0)

			goto err_resources;

	}



	err = dice_stream_start_packets(dice);

	if (err < 0)

		goto err_rx_channel;



	return 0;



err_rx_channel:

	channel = cpu_to_be32((u32)-1);

	snd_fw_transaction(dice->unit, TCODE_WRITE_QUADLET_REQUEST,

			   rx_address(dice, RX_ISOCHRONOUS), &channel, 4);

err_resources:

	fw_iso_resources_free(&dice->resources);

error:

	return err;

}



static void dice_stream_stop_packets(struct dice *dice)

{

	if (!dice->stream_running)

		return;



	dice_enable_clear(dice);



	amdtp_out_stream_stop(&dice->stream);



	dice->stream_running = false;

}



static void dice_stream_stop(struct dice *dice)

{

	__be32 channel;



	dice_stream_stop_packets(dice);



	if (!dice->resources.allocated)

		return;



	channel = cpu_to_be32((u32)-1);

	snd_fw_transaction(dice->unit, TCODE_WRITE_QUADLET_REQUEST,

			   rx_address(dice, RX_ISOCHRONOUS), &channel, 4);



	fw_iso_resources_free(&dice->resources);

}



static int dice_hw_params(struct snd_pcm_substream *substream,
@@ -586,7 +654,7 @@ static int dice_hw_params(struct snd_pcm_substream *substream, 
	int err;



	mutex_lock(&dice->mutex);

	dice_stop_stream(dice);

	dice_stream_stop(dice);

	mutex_unlock(&dice->mutex);



	err = snd_pcm_lib_alloc_vmalloc_buffer(substream,
@@ -608,7 +676,7 @@ static int dice_hw_free(struct snd_pcm_substream *substream) 
	struct dice *dice = substream->private_data;



	mutex_lock(&dice->mutex);

	dice_stop_stream(dice);

	dice_stream_stop(dice);

	mutex_unlock(&dice->mutex);



	return snd_pcm_lib_free_vmalloc_buffer(substream);
@@ -617,42 +685,17 @@ static int dice_hw_free(struct snd_pcm_substream *substream) 
static int dice_prepare(struct snd_pcm_substream *substream)

{

	struct dice *dice = substream->private_data;

	struct fw_device *device = fw_parent_device(dice->unit);

	__be32 channel;

	int err;



	mutex_lock(&dice->mutex);



	if (amdtp_out_streaming_error(&dice->stream))

		dice_stop_stream(dice);



	if (!dice->stream_running) {

		err = fw_iso_resources_allocate(&dice->resources,

				amdtp_out_stream_get_max_payload(&dice->stream),

				device->max_speed);

		if (err < 0)

			goto error;



		//TODO: RX_SEQ_START

		channel = cpu_to_be32(dice->resources.channel);

		err = snd_fw_transaction(dice->unit,

					 TCODE_WRITE_QUADLET_REQUEST,

					 rx_address(dice, RX_ISOCHRONOUS),

					 &channel, 4);

		if (err < 0)

			goto err_resources;

		dice_stream_stop_packets(dice);



		err = amdtp_out_stream_start(&dice->stream,

					     dice->resources.channel,

					     device->max_speed);

		if (err < 0)

			goto err_resources;



		err = dice_enable_set(dice);

		if (err < 0)

			goto err_stream;



		dice->stream_running = true;

	err = dice_stream_start(dice);

	if (err < 0) {

		mutex_unlock(&dice->mutex);

		return err;

	}



	mutex_unlock(&dice->mutex);
@@ -660,15 +703,6 @@ static int dice_prepare(struct snd_pcm_substream *substream) 
	amdtp_out_stream_pcm_prepare(&dice->stream);



	return 0;



err_stream:

	amdtp_out_stream_stop(&dice->stream);

err_resources:

	fw_iso_resources_free(&dice->resources);

error:

	mutex_unlock(&dice->mutex);



	return err;

}



static int dice_trigger(struct snd_pcm_substream *substream, int cmd)
@@ -941,7 +975,7 @@ static void dice_remove(struct fw_unit *unit) 


	mutex_lock(&dice->mutex);

	amdtp_out_stream_pcm_abort(&dice->stream);

	dice_stop_stream(dice);

	dice_stream_stop(dice);

	dice_owner_clear(dice);

	mutex_unlock(&dice->mutex);
@@ -953,8 +987,8 @@ static void dice_bus_reset(struct fw_unit *unit) 
	struct dice *dice = dev_get_drvdata(&unit->device);



	mutex_lock(&dice->mutex);



	/*

	 * XXX is the following true?

	 * On a bus reset, the DICE firmware disables streaming and then goes

	 * off contemplating its own navel for hundreds of milliseconds before

	 * it can react to any of our attempts to reenable streaming.  This
@@ -962,9 +996,13 @@ static void dice_bus_reset(struct fw_unit *unit) 
	 * to stop so that the application can restart them in an orderly

	 * manner.

	 */

	dice_owner_update(dice);

	amdtp_out_stream_pcm_abort(&dice->stream);

	dice_stop_stream(dice);

	dice_stream_stop_packets(dice);



	dice_owner_update(dice);



	fw_iso_resources_update(&dice->resources);



	mutex_unlock(&dice->mutex);

}