[alsa-devel] [PATCH 02/11] ALSA: digi00x: add streaming functionality

Takashi Sakamoto o-takashi at sakamocchi.jp
Sun Mar 15 17:01:00 CET 2015


This commit adds a functionality to manage streaming and to handle packets.

As long as seeing Digi 002, the device uses AMDTP stream in IEC 61883-1/6.
But the streaming is not controlled by CMP. It's controlled by writing to
certain addresses.

In Digi 002, several clock sources are available, while there're no
differences for packets in different clock sources. The value of SYT field
in transferred packets is always zero. Thus, streams in both direction don't
build synchronization. Tthis driver also ignores the synchronization.

And the device always requires received-stream to transmit packets, thus
the driver must transmit packets for both direction.

Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>
---
 sound/firewire/Kconfig                  |   1 +
 sound/firewire/digi00x/Makefile         |   2 +-
 sound/firewire/digi00x/digi00x-stream.c | 351 ++++++++++++++++++++++++++++++++
 sound/firewire/digi00x/digi00x.c        |  16 ++
 sound/firewire/digi00x/digi00x.h        |  52 +++++
 5 files changed, 421 insertions(+), 1 deletion(-)
 create mode 100644 sound/firewire/digi00x/digi00x-stream.c

diff --git a/sound/firewire/Kconfig b/sound/firewire/Kconfig
index 594b6d1..6b9b0a1 100644
--- a/sound/firewire/Kconfig
+++ b/sound/firewire/Kconfig
@@ -120,6 +120,7 @@ config SND_BEBOB
 
 config SND_DIGI00X
 	tristate "Digidesign 002/003 family support"
+	select SND_FIREWIRE_LIB
 	help
 	 Say Y here to include support for Digidesign 002/003 family.
 
diff --git a/sound/firewire/digi00x/Makefile b/sound/firewire/digi00x/Makefile
index e30e233..fe8fceb 100644
--- a/sound/firewire/digi00x/Makefile
+++ b/sound/firewire/digi00x/Makefile
@@ -1,2 +1,2 @@
-snd-digi00x-objs := digi00x.o
+snd-digi00x-objs := digi00x.o digi00x-stream.o
 obj-m += snd-digi00x.o
diff --git a/sound/firewire/digi00x/digi00x-stream.c b/sound/firewire/digi00x/digi00x-stream.c
new file mode 100644
index 0000000..75f67b5
--- /dev/null
+++ b/sound/firewire/digi00x/digi00x-stream.c
@@ -0,0 +1,351 @@
+/*
+ * digi00x-stream.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"
+
+#define CALLBACK_TIMEOUT 500
+
+const unsigned int snd_dg00x_stream_rates[SND_DG00X_RATE_COUNT] = {
+	[0] = 44100,
+	[1] = 48000,
+	[2] = 88200,
+	[3] = 96000,
+};
+
+/* Multi Bit Linear Audio data channels for each sampling transfer frequency. */
+const unsigned int
+snd_dg00x_stream_mbla_data_channels[SND_DG00X_RATE_COUNT] = {
+	/* Analog/ADAT/SPDIF */
+	[0] = (8 + 8 + 2),
+	[1] = (8 + 8 + 2),
+	/* Analog/SPDIF */
+	[2] = (8 + 2),
+	[3] = (8 + 2),
+};
+
+int snd_dg00x_stream_get_rate(struct snd_dg00x *dg00x, unsigned int *rate)
+{
+	__be32 data;
+	int err;
+
+	err = snd_fw_transaction(dg00x->unit, TCODE_READ_QUADLET_REQUEST,
+				 0xffffe0000110ull, &data, sizeof(data), 0);
+	if (err < 0)
+		goto end;
+
+	data = be32_to_cpu(data) & 0x0f;
+	if (data >= ARRAY_SIZE(snd_dg00x_stream_rates)) {
+		err = -EIO;
+		goto end;
+	}
+
+	*rate = snd_dg00x_stream_rates[data];
+end:
+	return err;
+}
+
+int snd_dg00x_stream_set_rate(struct snd_dg00x *dg00x, unsigned int rate)
+{
+	__be32 data;
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(snd_dg00x_stream_rates); i++) {
+		if (rate == snd_dg00x_stream_rates[i])
+			break;
+	}
+	if (i == ARRAY_SIZE(snd_dg00x_stream_rates))
+		return -EIO;
+
+	data = cpu_to_be32(i);
+	return snd_fw_transaction(dg00x->unit, TCODE_WRITE_QUADLET_REQUEST,
+				  0xffffe0000110ull, &data, sizeof(data), 0);
+}
+
+int snd_dg00x_stream_get_clock(struct snd_dg00x *dg00x,
+			       enum snd_dg00x_clock *clock)
+{
+	__be32 data;
+	int err;
+
+	err = snd_fw_transaction(dg00x->unit, TCODE_READ_QUADLET_REQUEST,
+				 0xffffe0000118ull, &data, sizeof(data), 0);
+	if (err < 0)
+		return err;
+
+	*clock = be32_to_cpu(data) & 0x0f;
+	if (*clock >= ARRAY_SIZE(snd_dg00x_stream_rates))
+		err = -EIO;
+
+	return err;
+}
+
+int snd_dg00x_stream_get_optical_mode(struct snd_dg00x *dg00x,
+				      enum snd_dg00x_optical_mode *mode)
+{
+	__be32 data;
+	int err;
+
+	err = snd_fw_transaction(dg00x->unit, TCODE_READ_QUADLET_REQUEST,
+				 0xffffe000011c, &data, sizeof(data), 0);
+	if (err >= 0)
+		*mode = be32_to_cpu(data) & 0x01;
+
+	return err;
+}
+
+static void finish_session(struct snd_dg00x *dg00x)
+{
+	__be32 data = cpu_to_be32(0x00000003);
+
+	snd_fw_transaction(dg00x->unit, TCODE_WRITE_QUADLET_REQUEST,
+			   0xffffe0000004ull, &data, sizeof(data), 0);
+}
+
+static int begin_session(struct snd_dg00x *dg00x)
+{
+	__be32 data;
+	u32 curr;
+	int err;
+
+	err = snd_fw_transaction(dg00x->unit,
+				 TCODE_READ_QUADLET_REQUEST,
+				 0xffffe0000000ull,
+				 &data, sizeof(data), 0);
+	if (err < 0)
+		goto error;
+	curr = be32_to_cpu(data);
+
+	if (curr == 0)
+		curr = 2;
+
+	curr--;
+	while (curr > 0) {
+		data = cpu_to_be32(curr);
+		err = snd_fw_transaction(dg00x->unit,
+					 TCODE_WRITE_QUADLET_REQUEST,
+					 0xffffe0000004ull,
+					 &data, sizeof(data), 0);
+		if (err < 0)
+			goto error;
+
+		msleep(20);
+		curr--;
+	}
+
+	return 0;
+error:
+	finish_session(dg00x);
+	return err;
+}
+
+static void release_resources(struct snd_dg00x *dg00x)
+{
+	__be32 data = 0;
+
+	/* Unregister isochronous channels for both direction. */
+	snd_fw_transaction(dg00x->unit, TCODE_WRITE_QUADLET_REQUEST,
+			   0xffffe0000100ull, &data, sizeof(data), 0);
+
+	/* Release isochronous resources. */
+	fw_iso_resources_free(&dg00x->tx_resources);
+	fw_iso_resources_free(&dg00x->rx_resources);
+}
+
+static int keep_resources(struct snd_dg00x *dg00x, unsigned int rate)
+{
+	unsigned int i, p;
+	__be32 data;
+	int err;
+
+	/* Check sampling rate. */
+	for (i = 0; i < SND_DG00X_RATE_COUNT; i++) {
+		if (snd_dg00x_stream_rates[i] == rate)
+			break;
+	}
+	if (i == SND_DG00X_RATE_COUNT)
+		return -EINVAL;
+
+	/* Keep resources for out-stream. */
+	amdtp_stream_set_parameters(&dg00x->rx_stream, rate,
+				    snd_dg00x_stream_mbla_data_channels[i], 2);
+	err = fw_iso_resources_allocate(&dg00x->rx_resources,
+				amdtp_stream_get_max_payload(&dg00x->rx_stream),
+				fw_parent_device(dg00x->unit)->max_speed);
+	if (err < 0)
+		return err;
+
+	/* Keep resources for in-stream. */
+	amdtp_stream_set_parameters(&dg00x->tx_stream, rate,
+				    snd_dg00x_stream_mbla_data_channels[i], 1);
+	err = fw_iso_resources_allocate(&dg00x->tx_resources,
+				amdtp_stream_get_max_payload(&dg00x->tx_stream),
+				fw_parent_device(dg00x->unit)->max_speed);
+	if (err < 0)
+		goto error;
+
+	/* Register isochronous channels for both direction. */
+	data = cpu_to_be32((dg00x->tx_resources.channel << 16) |
+			   dg00x->rx_resources.channel);
+	err = snd_fw_transaction(dg00x->unit, TCODE_WRITE_QUADLET_REQUEST,
+				 0xffffe0000100ull, &data, sizeof(data), 0);
+	if (err < 0)
+		goto error;
+
+	/* The first data channel in a packet is for MIDI conformant data. */
+	for (p = 0; p < snd_dg00x_stream_mbla_data_channels[i]; p++) {
+		dg00x->rx_stream.pcm_positions[p] = p + 1;
+		dg00x->tx_stream.pcm_positions[p] = p + 1;
+	}
+	dg00x->rx_stream.midi_position = 0;
+	dg00x->tx_stream.midi_position = 0;
+
+	return 0;
+error:
+	release_resources(dg00x);
+	return err;
+}
+
+int snd_dg00x_stream_init_duplex(struct snd_dg00x *dg00x)
+{
+	int err;
+
+	/* For out-stream. */
+	err = fw_iso_resources_init(&dg00x->rx_resources, dg00x->unit);
+	if (err < 0)
+		return err;
+	err = amdtp_stream_init(&dg00x->rx_stream, dg00x->unit,
+				AMDTP_OUT_STREAM, CIP_NONBLOCKING);
+
+	/* For in-stream. */
+	err = fw_iso_resources_init(&dg00x->tx_resources, dg00x->unit);
+	if (err < 0)
+		return err;
+	err = amdtp_stream_init(&dg00x->tx_stream, dg00x->unit,
+				AMDTP_IN_STREAM,
+				CIP_BLOCKING | CIP_SKIP_INIT_DBC_CHECK);
+	if (err < 0)
+		amdtp_stream_destroy(&dg00x->rx_stream);
+
+	return err;
+}
+
+/*
+ * This function should be called before starting streams or after stopping
+ * streams.
+ */
+void snd_dg00x_stream_destroy_duplex(struct snd_dg00x *dg00x)
+{
+	amdtp_stream_destroy(&dg00x->rx_stream);
+	fw_iso_resources_destroy(&dg00x->rx_resources);
+
+	amdtp_stream_destroy(&dg00x->tx_stream);
+	fw_iso_resources_destroy(&dg00x->tx_resources);
+}
+
+int snd_dg00x_stream_start_duplex(struct snd_dg00x *dg00x, unsigned int rate)
+{
+	unsigned int curr_rate;
+	int err = 0;
+
+	if (dg00x->playback_substreams == 0 &&
+	    dg00x->capture_substreams == 0)
+		goto end;
+
+	/* Check current sampling rate. */
+	err = snd_dg00x_stream_get_rate(dg00x, &curr_rate);
+	if (err < 0)
+		goto error;
+	if ((curr_rate != rate) |
+	    amdtp_streaming_error(&dg00x->tx_stream) |
+	    amdtp_streaming_error(&dg00x->rx_stream)) {
+		finish_session(dg00x);
+
+		amdtp_stream_stop(&dg00x->tx_stream);
+		amdtp_stream_stop(&dg00x->rx_stream);
+		release_resources(dg00x);
+	}
+
+	/* No streams are transmitted without receiving a stream. */
+	if (!amdtp_stream_running(&dg00x->rx_stream)) {
+		err = snd_dg00x_stream_set_rate(dg00x, rate);
+		if (err < 0)
+			goto error;
+
+		err = keep_resources(dg00x, rate);
+		if (err < 0)
+			goto error;
+
+		err = begin_session(dg00x);
+		if (err < 0)
+			goto error;
+
+		err = amdtp_stream_start(&dg00x->rx_stream,
+				dg00x->rx_resources.channel,
+				fw_parent_device(dg00x->unit)->max_speed);
+		if (err < 0)
+			goto error;
+
+		if (!amdtp_stream_wait_callback(&dg00x->rx_stream,
+						CALLBACK_TIMEOUT)) {
+			err = -ETIMEDOUT;
+			goto error;
+		}
+	}
+
+	/*
+	 * The value of SYT field in transmitted packets is always 0x0000. Thus,
+	 * duplex streams with timestamp synchronization cannot be built.
+	 */
+	if (dg00x->capture_substreams > 0 &&
+	    !amdtp_stream_running(&dg00x->tx_stream)) {
+		err = amdtp_stream_start(&dg00x->tx_stream,
+				dg00x->tx_resources.channel,
+				fw_parent_device(dg00x->unit)->max_speed);
+		if (err < 0)
+			goto error;
+
+		if (!amdtp_stream_wait_callback(&dg00x->tx_stream,
+						CALLBACK_TIMEOUT)) {
+			err = -ETIMEDOUT;
+			goto error;
+		}
+	}
+end:
+	return err;
+error:
+	finish_session(dg00x);
+
+	amdtp_stream_stop(&dg00x->tx_stream);
+	amdtp_stream_stop(&dg00x->rx_stream);
+	release_resources(dg00x);
+
+	return err;
+}
+
+void snd_dg00x_stream_stop_duplex(struct snd_dg00x *dg00x)
+{
+	if (dg00x->capture_substreams > 0)
+		return;
+	amdtp_stream_stop(&dg00x->tx_stream);
+
+	if (dg00x->playback_substreams > 0)
+		return;
+	finish_session(dg00x);
+	amdtp_stream_stop(&dg00x->rx_stream);
+	release_resources(dg00x);
+}
+
+/* TODO: investigation. */
+void snd_dg00x_stream_update_duplex(struct snd_dg00x *dg00x)
+{
+	fw_iso_resources_update(&dg00x->tx_resources);
+	fw_iso_resources_update(&dg00x->rx_resources);
+
+	amdtp_stream_update(&dg00x->tx_stream);
+	amdtp_stream_update(&dg00x->rx_stream);
+}
diff --git a/sound/firewire/digi00x/digi00x.c b/sound/firewire/digi00x/digi00x.c
index 6f427a2..b82bce7 100644
--- a/sound/firewire/digi00x/digi00x.c
+++ b/sound/firewire/digi00x/digi00x.c
@@ -47,6 +47,8 @@ static void dg00x_card_free(struct snd_card *card)
 {
 	struct snd_dg00x *dg00x = card->private_data;
 
+	snd_dg00x_stream_destroy_duplex(dg00x);
+
 	fw_unit_put(dg00x->unit);
 
 	mutex_destroy(&dg00x->mutex);
@@ -78,6 +80,10 @@ static int snd_dg00x_probe(struct fw_unit *unit,
 	if (err < 0)
 		goto error;
 
+	err = snd_dg00x_stream_init_duplex(dg00x);
+	if (err < 0)
+		goto error;
+
 	err = snd_card_register(card);
 	if (err < 0)
 		goto error;
@@ -90,6 +96,15 @@ error:
 	return err;
 }
 
+static void snd_dg00x_update(struct fw_unit *unit)
+{
+	struct snd_dg00x *dg00x = dev_get_drvdata(&unit->device);
+
+	mutex_lock(&dg00x->mutex);
+	snd_dg00x_stream_update_duplex(dg00x);
+	mutex_unlock(&dg00x->mutex);
+}
+
 static void snd_dg00x_remove(struct fw_unit *unit)
 {
 	struct snd_dg00x *dg00x = dev_get_drvdata(&unit->device);
@@ -118,6 +133,7 @@ static struct fw_driver dg00x_driver = {
 		.bus = &fw_bus_type,
 	},
 	.probe    = snd_dg00x_probe,
+	.update   = snd_dg00x_update,
 	.remove   = snd_dg00x_remove,
 	.id_table = snd_dg00x_id_table,
 };
diff --git a/sound/firewire/digi00x/digi00x.h b/sound/firewire/digi00x/digi00x.h
index 59425cd..61cfd6e 100644
--- a/sound/firewire/digi00x/digi00x.h
+++ b/sound/firewire/digi00x/digi00x.h
@@ -21,6 +21,11 @@
 #include <sound/core.h>
 #include <sound/initval.h>
 
+#include "../lib.h"
+#include "../packets-buffer.h"
+#include "../iso-resources.h"
+#include "../amdtp.h"
+
 struct snd_dg00x {
 	struct snd_card *card;
 	struct fw_unit *unit;
@@ -28,6 +33,53 @@ struct snd_dg00x {
 
 	struct mutex mutex;
 	spinlock_t lock;
+
+	struct amdtp_stream tx_stream;
+	struct fw_iso_resources tx_resources;
+
+	struct amdtp_stream rx_stream;
+	struct fw_iso_resources rx_resources;
+
+	unsigned int playback_substreams;
+	unsigned int capture_substreams;
+};
+
+/* values for SND_DG00X_ADDR_OFFSET_RATE */
+enum snd_dg00x_rate {
+	SND_DG00X_RATE_44100 = 0,
+	SND_DG00X_RATE_48000,
+	SND_DG00X_RATE_88200,
+	SND_DG00X_RATE_96000,
+	SND_DG00X_RATE_COUNT,
 };
 
+/* values for SND_DG00X_ADDR_OFFSET_CLOCK */
+enum snd_dg00x_clock {
+	SND_DG00X_CLOCK_INTERNAL = 0,
+	SND_DG00X_CLOCK_SPDIF,
+	SND_DG00X_CLOCK_ADAT,
+	SND_DG00X_CLOCK_WORD,
+};
+
+/* values for SND_DG00X_ADDR_OFFSET_OPTICAL_MODE */
+enum snd_dg00x_optical_mode {
+	SND_DG00X_OPTICAL_MODE_ADAT = 0,
+	SND_DG00X_OPTICAL_MODE_SPDIF,
+};
+
+extern const unsigned int snd_dg00x_stream_rates[SND_DG00X_RATE_COUNT];
+extern const unsigned int
+snd_dg00x_stream_mbla_data_channels[SND_DG00X_RATE_COUNT];
+int snd_dg00x_stream_get_rate(struct snd_dg00x *dg00x, unsigned int *rate);
+int snd_dg00x_stream_set_rate(struct snd_dg00x *dg00x, unsigned int rate);
+int snd_dg00x_stream_get_clock(struct snd_dg00x *dg00x,
+			       enum snd_dg00x_clock *clock);
+int snd_dg00x_stream_get_optical_mode(struct snd_dg00x *dg00x,
+				      enum snd_dg00x_optical_mode *mode);
+int snd_dg00x_stream_init_duplex(struct snd_dg00x *dg00x);
+int snd_dg00x_stream_start_duplex(struct snd_dg00x *dg00x, unsigned int rate);
+void snd_dg00x_stream_stop_duplex(struct snd_dg00x *dg00x);
+void snd_dg00x_stream_update_duplex(struct snd_dg00x *dg00x);
+void snd_dg00x_stream_destroy_duplex(struct snd_dg00x *dg00x);
+
 #endif
-- 
2.1.0



More information about the Alsa-devel mailing list