[alsa-devel] [PATCH 12/14] ALSA: dice: Add support for PCM capture

Takashi Sakamoto o-takashi at sakamocchi.jp
Sat Oct 4 13:27:22 CEST 2014


This commit adds a support for PCM capture.

When source of clock is external or opposite PCM substream is already running,
available sampling rate is limited at current one.

This driver give no way to change source of clock because it can be implemented
in user-land.

Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>
---
 sound/firewire/Kconfig         |   3 -
 sound/firewire/dice/dice-pcm.c | 139 +++++++++++++++++++++++++++++++++++++----
 2 files changed, 128 insertions(+), 14 deletions(-)

diff --git a/sound/firewire/Kconfig b/sound/firewire/Kconfig
index 46dff64..c8e704c 100644
--- a/sound/firewire/Kconfig
+++ b/sound/firewire/Kconfig
@@ -20,9 +20,6 @@ config SND_DICE
 	  Say Y here to include support for many DACs based on the DICE
 	  chip family (DICE-II/Jr/Mini) from TC Applied Technologies.
 
-	  At the moment, this driver supports playback only.  If you
-	  want to use devices that support capturing, use FFADO instead.
-
 	  To compile this driver as a module, choose M here: the module
 	  will be called snd-dice.
 
diff --git a/sound/firewire/dice/dice-pcm.c b/sound/firewire/dice/dice-pcm.c
index a0dbe0c..3427a21 100644
--- a/sound/firewire/dice/dice-pcm.c
+++ b/sound/firewire/dice/dice-pcm.c
@@ -12,7 +12,8 @@
 static int dice_rate_constraint(struct snd_pcm_hw_params *params,
 				struct snd_pcm_hw_rule *rule)
 {
-	struct snd_dice *dice = rule->private;
+	struct snd_pcm_substream *substream = rule->private;
+	struct snd_dice *dice = substream->private_data;
 
 	const struct snd_interval *c =
 		hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_CHANNELS);
@@ -21,7 +22,12 @@ static int dice_rate_constraint(struct snd_pcm_hw_params *params,
 	struct snd_interval rates = {
 		.min = UINT_MAX, .max = 0, .integer = 1
 	};
-	unsigned int i, rate, mode, *pcm_channels = dice->rx_channels;
+	unsigned int i, rate, mode, *pcm_channels;
+
+	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+		pcm_channels = dice->tx_channels;
+	else
+		pcm_channels = dice->rx_channels;
 
 	for (i = 0; i < ARRAY_SIZE(snd_dice_rates); ++i) {
 		rate = snd_dice_rates[i];
@@ -41,7 +47,8 @@ static int dice_rate_constraint(struct snd_pcm_hw_params *params,
 static int dice_channels_constraint(struct snd_pcm_hw_params *params,
 				    struct snd_pcm_hw_rule *rule)
 {
-	struct snd_dice *dice = rule->private;
+	struct snd_pcm_substream *substream = rule->private;
+	struct snd_dice *dice = substream->private_data;
 
 	const struct snd_interval *r =
 		hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_RATE);
@@ -50,7 +57,12 @@ static int dice_channels_constraint(struct snd_pcm_hw_params *params,
 	struct snd_interval channels = {
 		.min = UINT_MAX, .max = 0, .integer = 1
 	};
-	unsigned int i, rate, mode, *pcm_channels = dice->rx_channels;
+	unsigned int i, rate, mode, *pcm_channels;
+
+	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+		pcm_channels = dice->tx_channels;
+	else
+		pcm_channels = dice->rx_channels;
 
 	for (i = 0; i < ARRAY_SIZE(snd_dice_rates); ++i) {
 		rate = snd_dice_rates[i];
@@ -109,30 +121,42 @@ static int init_hw_info(struct snd_dice *dice,
 {
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	struct snd_pcm_hardware *hw = &runtime->hw;
+	struct amdtp_stream *stream;
+	unsigned int *pcm_channels;
 	int err;
 
 	hw->info = SNDRV_PCM_INFO_MMAP |
 		   SNDRV_PCM_INFO_MMAP_VALID |
 		   SNDRV_PCM_INFO_BATCH |
 		   SNDRV_PCM_INFO_INTERLEAVED |
+		   SNDRV_PCM_INFO_JOINT_DUPLEX |
 		   SNDRV_PCM_INFO_BLOCK_TRANSFER;
-	hw->formats = AMDTP_OUT_PCM_FORMAT_BITS;
 
-	limit_channels_and_rates(dice, runtime, dice->rx_channels);
+	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
+		hw->formats = AMDTP_IN_PCM_FORMAT_BITS;
+		stream = &dice->tx_stream;
+		pcm_channels = dice->tx_channels;
+	} else {
+		hw->formats = AMDTP_OUT_PCM_FORMAT_BITS;
+		stream = &dice->rx_stream;
+		pcm_channels = dice->rx_channels;
+	}
+
+	limit_channels_and_rates(dice, runtime, pcm_channels);
 	limit_period_and_buffer(hw);
 
 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
-				  dice_rate_constraint, dice,
+				  dice_rate_constraint, substream,
 				  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
 	if (err < 0)
 		goto end;
 	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
-				  dice_channels_constraint, dice,
+				  dice_channels_constraint, substream,
 				  SNDRV_PCM_HW_PARAM_RATE, -1);
 	if (err < 0)
 		goto end;
 
-	err = amdtp_stream_add_pcm_hw_constraints(&dice->rx_stream, runtime);
+	err = amdtp_stream_add_pcm_hw_constraints(stream, runtime);
 end:
 	return err;
 }
@@ -202,10 +226,28 @@ static int pcm_close(struct snd_pcm_substream *substream)
 	return 0;
 }
 
+static int capture_hw_params(struct snd_pcm_substream *substream,
+			     struct snd_pcm_hw_params *hw_params)
+{
+	struct snd_dice *dice = substream->private_data;
+
+	if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN)
+		atomic_inc(&dice->substreams_counter);
+
+	amdtp_stream_set_pcm_format(&dice->tx_stream,
+				    params_format(hw_params));
+
+	return snd_pcm_lib_alloc_vmalloc_buffer(substream,
+						params_buffer_bytes(hw_params));
+}
 static int playback_hw_params(struct snd_pcm_substream *substream,
 			      struct snd_pcm_hw_params *hw_params)
 {
 	struct snd_dice *dice = substream->private_data;
+
+	if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN)
+		atomic_inc(&dice->substreams_counter);
+
 	amdtp_stream_set_pcm_format(&dice->rx_stream,
 				    params_format(hw_params));
 
@@ -213,15 +255,41 @@ static int playback_hw_params(struct snd_pcm_substream *substream,
 						params_buffer_bytes(hw_params));
 }
 
+static int capture_hw_free(struct snd_pcm_substream *substream)
+{
+	struct snd_dice *dice = substream->private_data;
+
+	if (substream->runtime->status->state != SNDRV_PCM_STATE_OPEN)
+		atomic_dec(&dice->substreams_counter);
+
+	snd_dice_stream_stop_duplex(dice);
+
+	return snd_pcm_lib_free_vmalloc_buffer(substream);
+}
+
 static int playback_hw_free(struct snd_pcm_substream *substream)
 {
 	struct snd_dice *dice = substream->private_data;
 
+	if (substream->runtime->status->state != SNDRV_PCM_STATE_OPEN)
+		atomic_dec(&dice->substreams_counter);
+
 	snd_dice_stream_stop_duplex(dice);
 
 	return snd_pcm_lib_free_vmalloc_buffer(substream);
 }
 
+static int capture_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_dice *dice = substream->private_data;
+	int err;
+
+	err = snd_dice_stream_start_duplex(dice, substream->runtime->rate);
+	if (err >= 0)
+		amdtp_stream_pcm_prepare(&dice->tx_stream);
+
+	return 0;
+}
 static int playback_prepare(struct snd_pcm_substream *substream)
 {
 	struct snd_dice *dice = substream->private_data;
@@ -234,6 +302,23 @@ static int playback_prepare(struct snd_pcm_substream *substream)
 	return err;
 }
 
+static int capture_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_dice *dice = substream->private_data;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		amdtp_stream_pcm_trigger(&dice->tx_stream, substream);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+		amdtp_stream_pcm_trigger(&dice->tx_stream, NULL);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
 static int playback_trigger(struct snd_pcm_substream *substream, int cmd)
 {
 	struct snd_dice *dice = substream->private_data;
@@ -252,6 +337,12 @@ static int playback_trigger(struct snd_pcm_substream *substream, int cmd)
 	return 0;
 }
 
+static snd_pcm_uframes_t capture_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_dice *dice = substream->private_data;
+
+	return amdtp_stream_pcm_pointer(&dice->tx_stream);
+}
 static snd_pcm_uframes_t playback_pointer(struct snd_pcm_substream *substream)
 {
 	struct snd_dice *dice = substream->private_data;
@@ -261,6 +352,18 @@ static snd_pcm_uframes_t playback_pointer(struct snd_pcm_substream *substream)
 
 int snd_dice_create_pcm(struct snd_dice *dice)
 {
+	static struct snd_pcm_ops capture_ops = {
+		.open      = pcm_open,
+		.close     = pcm_close,
+		.ioctl     = snd_pcm_lib_ioctl,
+		.hw_params = capture_hw_params,
+		.hw_free   = capture_hw_free,
+		.prepare   = capture_prepare,
+		.trigger   = capture_trigger,
+		.pointer   = capture_pointer,
+		.page      = snd_pcm_lib_get_vmalloc_page,
+		.mmap      = snd_pcm_lib_mmap_vmalloc,
+	};
 	static struct snd_pcm_ops playback_ops = {
 		.open      = pcm_open,
 		.close     = pcm_close,
@@ -274,14 +377,28 @@ int snd_dice_create_pcm(struct snd_dice *dice)
 		.mmap      = snd_pcm_lib_mmap_vmalloc,
 	};
 	struct snd_pcm *pcm;
+	unsigned int i, capture, playback;
 	int err;
 
-	err = snd_pcm_new(dice->card, "DICE", 0, 1, 0, &pcm);
+	capture = playback = 0;
+	for (i = 0; i < 3; i++) {
+		if (dice->tx_channels[i] > 0)
+			capture = 1;
+		if (dice->rx_channels[i] > 0)
+			playback = 1;
+	}
+
+	err = snd_pcm_new(dice->card, "DICE", 0, playback, capture, &pcm);
 	if (err < 0)
 		return err;
 	pcm->private_data = dice;
 	strcpy(pcm->name, dice->card->shortname);
-	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &playback_ops);
+
+	if (capture > 0)
+		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &capture_ops);
+
+	if (playback > 0)
+		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &playback_ops);
 
 	return 0;
 }
-- 
1.9.1



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