[alsa-devel] [PATCH 04/11] ALSA: digi00x: add PCM functionality

Takashi Sakamoto o-takashi at sakamocchi.jp
Sun Mar 15 17:01:02 CET 2015


As long as seeing Digi 002, any PCM samples are transferred by Multi Bit
Linear Audio data channel in AMDTP packet. There're no quirks.

On the other hand, for received packets, the device expects drivers to use
a certain algorism to multiplex PCM samples into packets.

This commit adds PCM functionality to transmit/receive PCM samples with
current ALSA AMDTP engine, thus PCM playback substream causes noisy sound.

Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>
---
 sound/firewire/digi00x/Makefile      |   2 +-
 sound/firewire/digi00x/digi00x-pcm.c | 325 +++++++++++++++++++++++++++++++++++
 sound/firewire/digi00x/digi00x.c     |   4 +
 sound/firewire/digi00x/digi00x.h     |   4 +
 4 files changed, 334 insertions(+), 1 deletion(-)
 create mode 100644 sound/firewire/digi00x/digi00x-pcm.c

diff --git a/sound/firewire/digi00x/Makefile b/sound/firewire/digi00x/Makefile
index aaec823..f2ed472 100644
--- a/sound/firewire/digi00x/Makefile
+++ b/sound/firewire/digi00x/Makefile
@@ -1,2 +1,2 @@
-snd-digi00x-objs := digi00x.o digi00x-stream.o digi00x-proc.o
+snd-digi00x-objs := digi00x.o digi00x-stream.o digi00x-proc.o digi00x-pcm.o
 obj-m += snd-digi00x.o
diff --git a/sound/firewire/digi00x/digi00x-pcm.c b/sound/firewire/digi00x/digi00x-pcm.c
new file mode 100644
index 0000000..4522b38
--- /dev/null
+++ b/sound/firewire/digi00x/digi00x-pcm.c
@@ -0,0 +1,325 @@
+/*
+ * digi00x-pcm.c - a part of driver for Digidesign Digi 002/003 family
+ *
+ * Copyright (c) 2014-2015 Takashi Sakamoto
+ *
+ * Licensed under the terms of the GNU General Public License, version 2.
+ */
+
+#include "digi00x.h"
+
+static int hw_rule_rate(struct snd_pcm_hw_params *params,
+			struct snd_pcm_hw_rule *rule)
+{
+	struct snd_interval *r =
+		hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
+	const struct snd_interval *c =
+		hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_CHANNELS);
+	struct snd_interval t = {
+		.min = UINT_MAX, .max = 0, .integer = 1,
+	};
+	unsigned int i;
+
+	for (i = 0; i < SND_DG00X_RATE_COUNT; i++) {
+		if (!snd_interval_test(c,
+				       snd_dg00x_stream_mbla_data_channels[i]))
+			continue;
+
+		t.min = min(t.min, snd_dg00x_stream_rates[i]);
+		t.max = max(t.max, snd_dg00x_stream_rates[i]);
+	}
+
+	return snd_interval_refine(r, &t);
+}
+
+static int hw_rule_channels(struct snd_pcm_hw_params *params,
+			    struct snd_pcm_hw_rule *rule)
+{
+	struct snd_interval *c =
+		hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
+	const struct snd_interval *r =
+		hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_RATE);
+	struct snd_interval t = {
+		.min = UINT_MAX, .max = 0, .integer = 1,
+	};
+	unsigned int i;
+
+	for (i = 0; i < SND_DG00X_RATE_COUNT; i++) {
+		if (!snd_interval_test(r, snd_dg00x_stream_rates[i]))
+			continue;
+
+		t.min = min(t.min, snd_dg00x_stream_mbla_data_channels[i]);
+		t.max = max(t.max, snd_dg00x_stream_mbla_data_channels[i]);
+	}
+
+	return snd_interval_refine(c, &t);
+}
+
+static int pcm_init_hw_params(struct snd_dg00x *dg00x,
+			      struct snd_pcm_substream *substream)
+{
+	static const struct snd_pcm_hardware hardware = {
+		.info = SNDRV_PCM_INFO_BATCH |
+			SNDRV_PCM_INFO_BLOCK_TRANSFER |
+			SNDRV_PCM_INFO_INTERLEAVED |
+			SNDRV_PCM_INFO_JOINT_DUPLEX |
+			SNDRV_PCM_INFO_MMAP |
+			SNDRV_PCM_INFO_MMAP_VALID,
+		.formats = SNDRV_PCM_FMTBIT_S32,
+		.rates = SNDRV_PCM_RATE_44100 |
+			 SNDRV_PCM_RATE_48000 |
+			 SNDRV_PCM_RATE_88200 |
+			 SNDRV_PCM_RATE_96000,
+		.rate_min = 44100,
+		.rate_max = 96000,
+		.channels_min = 10,
+		.channels_max = 18,
+		.period_bytes_min = 4 * 18,
+		.period_bytes_max = 4 * 18 * 2048,
+		.buffer_bytes_max = 4 * 18 * 2048 * 2,
+		.periods_min = 2,
+		.periods_max = UINT_MAX,
+	};
+	int err;
+
+	substream->runtime->hw = hardware;
+
+	err = snd_pcm_hw_rule_add(substream->runtime, 0,
+				  SNDRV_PCM_HW_PARAM_CHANNELS,
+				  hw_rule_channels, NULL,
+				  SNDRV_PCM_HW_PARAM_RATE, -1);
+	if (err < 0)
+		goto end;
+
+	err = snd_pcm_hw_rule_add(substream->runtime, 0,
+				  SNDRV_PCM_HW_PARAM_RATE,
+				  hw_rule_rate, NULL,
+				  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
+	if (err < 0)
+		goto end;
+
+	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+		err = amdtp_stream_add_pcm_hw_constraints(&dg00x->tx_stream,
+							  substream->runtime);
+	else
+		err = amdtp_stream_add_pcm_hw_constraints(&dg00x->rx_stream,
+							  substream->runtime);
+end:
+	return err;
+}
+
+static int pcm_open(struct snd_pcm_substream *substream)
+{
+	struct snd_dg00x *dg00x = substream->private_data;
+	enum snd_dg00x_clock clock;
+	unsigned int rate;
+	int err;
+
+	err = pcm_init_hw_params(dg00x, substream);
+	if (err < 0)
+		return err;
+
+	err = snd_dg00x_stream_get_clock(dg00x, &clock);
+	if (clock != SND_DG00X_CLOCK_INTERNAL) {
+		err = snd_dg00x_stream_get_rate(dg00x, &rate);
+		if (err < 0)
+			return err;
+		substream->runtime->hw.rate_min = rate;
+		substream->runtime->hw.rate_max = rate;
+	}
+
+	snd_pcm_set_sync(substream);
+
+	return 0;
+}
+
+static int pcm_close(struct snd_pcm_substream *substream)
+{
+	return 0;
+}
+
+static int pcm_capture_hw_params(struct snd_pcm_substream *substream,
+				 struct snd_pcm_hw_params *hw_params)
+{
+	struct snd_dg00x *dg00x = substream->private_data;
+
+	if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN) {
+		mutex_lock(&dg00x->mutex);
+		dg00x->capture_substreams++;
+		mutex_unlock(&dg00x->mutex);
+	}
+	amdtp_stream_set_pcm_format(&dg00x->tx_stream,
+				    params_format(hw_params));
+	return snd_pcm_lib_alloc_vmalloc_buffer(substream,
+						params_buffer_bytes(hw_params));
+}
+static int pcm_playback_hw_params(struct snd_pcm_substream *substream,
+				  struct snd_pcm_hw_params *hw_params)
+{
+	struct snd_dg00x *dg00x = substream->private_data;
+
+	if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN) {
+		mutex_lock(&dg00x->mutex);
+		dg00x->playback_substreams++;
+		mutex_unlock(&dg00x->mutex);
+	}
+	amdtp_stream_set_pcm_format(&dg00x->rx_stream,
+				    params_format(hw_params));
+	return snd_pcm_lib_alloc_vmalloc_buffer(substream,
+						params_buffer_bytes(hw_params));
+}
+
+static int pcm_capture_hw_free(struct snd_pcm_substream *substream)
+{
+	struct snd_dg00x *dg00x = substream->private_data;
+
+	mutex_lock(&dg00x->mutex);
+
+	if (substream->runtime->status->state != SNDRV_PCM_STATE_OPEN)
+		dg00x->capture_substreams--;
+
+	snd_dg00x_stream_stop_duplex(dg00x);
+
+	mutex_unlock(&dg00x->mutex);
+
+	return snd_pcm_lib_free_vmalloc_buffer(substream);
+}
+static int pcm_playback_hw_free(struct snd_pcm_substream *substream)
+{
+	struct snd_dg00x *dg00x = substream->private_data;
+
+	mutex_lock(&dg00x->mutex);
+
+	if (substream->runtime->status->state != SNDRV_PCM_STATE_OPEN)
+		dg00x->playback_substreams--;
+
+	snd_dg00x_stream_stop_duplex(dg00x);
+
+	mutex_unlock(&dg00x->mutex);
+
+	return snd_pcm_lib_free_vmalloc_buffer(substream);
+}
+
+static int pcm_capture_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_dg00x *dg00x = substream->private_data;
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	int err;
+
+	mutex_lock(&dg00x->mutex);
+
+	err = snd_dg00x_stream_start_duplex(dg00x, runtime->rate);
+	if (err >= 0)
+		amdtp_stream_pcm_prepare(&dg00x->tx_stream);
+
+	mutex_unlock(&dg00x->mutex);
+
+	return err;
+}
+static int pcm_playback_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_dg00x *dg00x = substream->private_data;
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	int err;
+
+	mutex_lock(&dg00x->mutex);
+
+	err = snd_dg00x_stream_start_duplex(dg00x, runtime->rate);
+	if (err >= 0)
+		amdtp_stream_pcm_prepare(&dg00x->rx_stream);
+
+	mutex_unlock(&dg00x->mutex);
+
+	return err;
+}
+
+static int pcm_capture_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_dg00x *dg00x = substream->private_data;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		amdtp_stream_pcm_trigger(&dg00x->tx_stream, substream);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+		amdtp_stream_pcm_trigger(&dg00x->tx_stream, NULL);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+static int pcm_playback_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_dg00x *dg00x = substream->private_data;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		amdtp_stream_pcm_trigger(&dg00x->rx_stream, substream);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+		amdtp_stream_pcm_trigger(&dg00x->rx_stream, NULL);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static snd_pcm_uframes_t pcm_capture_pointer(struct snd_pcm_substream *sbstrm)
+{
+	struct snd_dg00x *dg00x = sbstrm->private_data;
+
+	return amdtp_stream_pcm_pointer(&dg00x->tx_stream);
+}
+static snd_pcm_uframes_t pcm_playback_pointer(struct snd_pcm_substream *sbstrm)
+{
+	struct snd_dg00x *dg00x = sbstrm->private_data;
+
+	return amdtp_stream_pcm_pointer(&dg00x->rx_stream);
+}
+
+static struct snd_pcm_ops pcm_capture_ops = {
+	.open		= pcm_open,
+	.close		= pcm_close,
+	.ioctl		= snd_pcm_lib_ioctl,
+	.hw_params	= pcm_capture_hw_params,
+	.hw_free	= pcm_capture_hw_free,
+	.prepare	= pcm_capture_prepare,
+	.trigger	= pcm_capture_trigger,
+	.pointer	= pcm_capture_pointer,
+	.page		= snd_pcm_lib_get_vmalloc_page,
+};
+static struct snd_pcm_ops pcm_playback_ops = {
+	.open		= pcm_open,
+	.close		= pcm_close,
+	.ioctl		= snd_pcm_lib_ioctl,
+	.hw_params	= pcm_playback_hw_params,
+	.hw_free	= pcm_playback_hw_free,
+	.prepare	= pcm_playback_prepare,
+	.trigger	= pcm_playback_trigger,
+	.pointer	= pcm_playback_pointer,
+	.page		= snd_pcm_lib_get_vmalloc_page,
+	.mmap		= snd_pcm_lib_mmap_vmalloc,
+};
+
+int snd_dg00x_create_pcm_devices(struct snd_dg00x *dg00x)
+{
+	struct snd_pcm *pcm;
+	int err;
+
+	err = snd_pcm_new(dg00x->card, dg00x->card->driver, 0, 1, 1, &pcm);
+	if (err < 0)
+		return err;
+
+	pcm->private_data = dg00x;
+	snprintf(pcm->name, sizeof(pcm->name),
+		 "%s PCM", dg00x->card->shortname);
+	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &pcm_playback_ops);
+	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &pcm_capture_ops);
+
+	return 0;
+}
+
diff --git a/sound/firewire/digi00x/digi00x.c b/sound/firewire/digi00x/digi00x.c
index d9c9e14..493437a 100644
--- a/sound/firewire/digi00x/digi00x.c
+++ b/sound/firewire/digi00x/digi00x.c
@@ -86,6 +86,10 @@ static int snd_dg00x_probe(struct fw_unit *unit,
 
 	snd_dg00x_proc_init(dg00x);
 
+	err = snd_dg00x_create_pcm_devices(dg00x);
+	if (err < 0)
+		goto error;
+
 	err = snd_card_register(card);
 	if (err < 0)
 		goto error;
diff --git a/sound/firewire/digi00x/digi00x.h b/sound/firewire/digi00x/digi00x.h
index dde039f..754486a 100644
--- a/sound/firewire/digi00x/digi00x.h
+++ b/sound/firewire/digi00x/digi00x.h
@@ -21,6 +21,8 @@
 #include <sound/core.h>
 #include <sound/initval.h>
 #include <sound/info.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
 
 #include "../lib.h"
 #include "../packets-buffer.h"
@@ -84,4 +86,6 @@ void snd_dg00x_stream_update_duplex(struct snd_dg00x *dg00x);
 void snd_dg00x_stream_destroy_duplex(struct snd_dg00x *dg00x);
 
 void snd_dg00x_proc_init(struct snd_dg00x *dg00x);
+
+int snd_dg00x_create_pcm_devices(struct snd_dg00x *dg00x);
 #endif
-- 
2.1.0



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