Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

16 files changed, 4303 insertions, 0 deletions

diff --git a/sound/firewire/motu/Makefile b/sound/firewire/motu/Makefile
new file mode 100644
index 000000000..3bef2a0b1
--- /dev/null
+++ b/sound/firewire/motu/Makefile
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0
+CFLAGS_amdtp-motu.o	:= -I$(src)
+
+snd-firewire-motu-objs := motu.o amdtp-motu.o motu-transaction.o motu-stream.o \
+			  motu-proc.o motu-pcm.o motu-midi.o motu-hwdep.o \
+			  motu-protocol-v2.o motu-protocol-v3.o \
+			  motu-protocol-v1.o motu-register-dsp-message-parser.o \
+			  motu-command-dsp-message-parser.o
+obj-$(CONFIG_SND_FIREWIRE_MOTU) += snd-firewire-motu.o
diff --git a/sound/firewire/motu/amdtp-motu-trace.h b/sound/firewire/motu/amdtp-motu-trace.h
new file mode 100644
index 000000000..3d36f125c
--- /dev/null
+++ b/sound/firewire/motu/amdtp-motu-trace.h
@@ -0,0 +1,85 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * amdtp-motu-trace.h - tracepoint definitions to dump a part of packet data
+ *
+ * Copyright (c) 2017 Takashi Sakamoto
+ */
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM		snd_firewire_motu
+
+#if !defined(_SND_FIREWIRE_MOTU_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _SND_FIREWIRE_MOTU_TRACE_H
+
+#include <linux/tracepoint.h>
+
+static void copy_sph(u32 *frame, __be32 *buffer, unsigned int data_blocks,
+		     unsigned int data_block_quadlets);
+static void copy_message(u64 *frames, __be32 *buffer, unsigned int data_blocks,
+			 unsigned int data_block_quadlets);
+
+TRACE_EVENT(data_block_sph,
+	TP_PROTO(struct amdtp_stream *s, unsigned int data_blocks, __be32 *buffer),
+	TP_ARGS(s, data_blocks, buffer),
+	TP_STRUCT__entry(
+		__field(int, src)
+		__field(int, dst)
+		__field(unsigned int, data_blocks)
+		__dynamic_array(u32, tstamps, data_blocks)
+	),
+	TP_fast_assign(
+		if (s->direction == AMDTP_IN_STREAM) {
+			__entry->src = fw_parent_device(s->unit)->node_id;
+			__entry->dst = fw_parent_device(s->unit)->card->node_id;
+		} else {
+			__entry->src = fw_parent_device(s->unit)->card->node_id;
+			__entry->dst = fw_parent_device(s->unit)->node_id;
+		}
+		__entry->data_blocks = data_blocks;
+		copy_sph(__get_dynamic_array(tstamps), buffer, data_blocks, s->data_block_quadlets);
+	),
+	TP_printk(
+		"%04x %04x %u %s",
+		__entry->src,
+		__entry->dst,
+		__entry->data_blocks,
+		__print_array(__get_dynamic_array(tstamps), __entry->data_blocks, 4)
+	)
+);
+
+TRACE_EVENT(data_block_message,
+	TP_PROTO(struct amdtp_stream *s, unsigned int data_blocks, __be32 *buffer),
+	TP_ARGS(s, data_blocks, buffer),
+	TP_STRUCT__entry(
+		__field(int, src)
+		__field(int, dst)
+		__field(unsigned int, data_blocks)
+		__dynamic_array(u64, messages, data_blocks)
+	),
+	TP_fast_assign(
+		if (s->direction == AMDTP_IN_STREAM) {
+			__entry->src = fw_parent_device(s->unit)->node_id;
+			__entry->dst = fw_parent_device(s->unit)->card->node_id;
+		} else {
+			__entry->src = fw_parent_device(s->unit)->card->node_id;
+			__entry->dst = fw_parent_device(s->unit)->node_id;
+		}
+		__entry->data_blocks = data_blocks;
+		copy_message(__get_dynamic_array(messages), buffer, data_blocks, s->data_block_quadlets);
+	),
+	TP_printk(
+		"%04x %04x %u %s",
+		__entry->src,
+		__entry->dst,
+		__entry->data_blocks,
+		__print_array(__get_dynamic_array(messages), __entry->data_blocks, 8)
+	)
+);
+
+#endif
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH	.
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE	amdtp-motu-trace
+#include <trace/define_trace.h>
diff --git a/sound/firewire/motu/amdtp-motu.c b/sound/firewire/motu/amdtp-motu.c
new file mode 100644
index 000000000..2fb52f481
--- /dev/null
+++ b/sound/firewire/motu/amdtp-motu.c
@@ -0,0 +1,489 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * amdtp-motu.c - a part of driver for MOTU FireWire series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ */
+
+#include <linux/slab.h>
+#include <sound/pcm.h>
+#include "motu.h"
+
+#define CREATE_TRACE_POINTS
+#include "amdtp-motu-trace.h"
+
+#define CIP_FMT_MOTU		0x02
+#define CIP_FMT_MOTU_TX_V3	0x22
+#define MOTU_FDF_AM824		0x22
+
+#define TICKS_PER_CYCLE		3072
+#define CYCLES_PER_SECOND	8000
+#define TICKS_PER_SECOND	(TICKS_PER_CYCLE * CYCLES_PER_SECOND)
+
+#define CIP_SPH_CYCLE_SHIFT	12
+#define CIP_SPH_CYCLE_MASK	0x01fff000
+#define CIP_SPH_OFFSET_MASK	0x00000fff
+
+/*
+ * Nominally 3125 bytes/second, but the MIDI port's clock might be
+ * 1% too slow, and the bus clock 100 ppm too fast.
+ */
+#define MIDI_BYTES_PER_SECOND	3093
+
+struct amdtp_motu {
+	unsigned int pcm_chunks;
+	unsigned int pcm_byte_offset;
+
+	struct snd_rawmidi_substream *midi;
+	unsigned int midi_ports;
+	unsigned int midi_flag_offset;
+	unsigned int midi_byte_offset;
+
+	int midi_db_count;
+	unsigned int midi_db_interval;
+
+	struct amdtp_motu_cache *cache;
+};
+
+int amdtp_motu_set_parameters(struct amdtp_stream *s, unsigned int rate,
+			      unsigned int midi_ports,
+			      struct snd_motu_packet_format *formats)
+{
+	struct amdtp_motu *p = s->protocol;
+	unsigned int pcm_chunks, data_chunks, data_block_quadlets;
+	unsigned int mode;
+	int i, err;
+
+	if (amdtp_stream_running(s))
+		return -EBUSY;
+
+	for (i = 0; i < ARRAY_SIZE(snd_motu_clock_rates); ++i) {
+		if (snd_motu_clock_rates[i] == rate) {
+			mode = i >> 1;
+			break;
+		}
+	}
+	if (i == ARRAY_SIZE(snd_motu_clock_rates))
+		return -EINVAL;
+
+	// Each data block includes SPH in its head. Data chunks follow with
+	// 3 byte alignment. Padding follows with zero to conform to quadlet
+	// alignment.
+	pcm_chunks = formats->pcm_chunks[mode];
+	data_chunks = formats->msg_chunks + pcm_chunks;
+	data_block_quadlets = 1 + DIV_ROUND_UP(data_chunks * 3, 4);
+
+	err = amdtp_stream_set_parameters(s, rate, data_block_quadlets);
+	if (err < 0)
+		return err;
+
+	p->pcm_chunks = pcm_chunks;
+	p->pcm_byte_offset = formats->pcm_byte_offset;
+
+	p->midi_ports = midi_ports;
+	p->midi_flag_offset = formats->midi_flag_offset;
+	p->midi_byte_offset = formats->midi_byte_offset;
+
+	p->midi_db_count = 0;
+	p->midi_db_interval = rate / MIDI_BYTES_PER_SECOND;
+
+	return 0;
+}
+
+static void read_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
+			 __be32 *buffer, unsigned int data_blocks,
+			 unsigned int pcm_frames)
+{
+	struct amdtp_motu *p = s->protocol;
+	unsigned int channels = p->pcm_chunks;
+	struct snd_pcm_runtime *runtime = pcm->runtime;
+	unsigned int pcm_buffer_pointer;
+	int remaining_frames;
+	u8 *byte;
+	u32 *dst;
+	int i, c;
+
+	pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
+	pcm_buffer_pointer %= runtime->buffer_size;
+
+	dst = (void *)runtime->dma_area +
+				frames_to_bytes(runtime, pcm_buffer_pointer);
+	remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
+
+	for (i = 0; i < data_blocks; ++i) {
+		byte = (u8 *)buffer + p->pcm_byte_offset;
+
+		for (c = 0; c < channels; ++c) {
+			*dst = (byte[0] << 24) |
+			       (byte[1] << 16) |
+			       (byte[2] << 8);
+			byte += 3;
+			dst++;
+		}
+		buffer += s->data_block_quadlets;
+		if (--remaining_frames == 0)
+			dst = (void *)runtime->dma_area;
+	}
+}
+
+static void write_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
+			  __be32 *buffer, unsigned int data_blocks,
+			  unsigned int pcm_frames)
+{
+	struct amdtp_motu *p = s->protocol;
+	unsigned int channels = p->pcm_chunks;
+	struct snd_pcm_runtime *runtime = pcm->runtime;
+	unsigned int pcm_buffer_pointer;
+	int remaining_frames;
+	u8 *byte;
+	const u32 *src;
+	int i, c;
+
+	pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
+	pcm_buffer_pointer %= runtime->buffer_size;
+
+	src = (void *)runtime->dma_area +
+				frames_to_bytes(runtime, pcm_buffer_pointer);
+	remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
+
+	for (i = 0; i < data_blocks; ++i) {
+		byte = (u8 *)buffer + p->pcm_byte_offset;
+
+		for (c = 0; c < channels; ++c) {
+			byte[0] = (*src >> 24) & 0xff;
+			byte[1] = (*src >> 16) & 0xff;
+			byte[2] = (*src >>  8) & 0xff;
+			byte += 3;
+			src++;
+		}
+
+		buffer += s->data_block_quadlets;
+		if (--remaining_frames == 0)
+			src = (void *)runtime->dma_area;
+	}
+}
+
+static void write_pcm_silence(struct amdtp_stream *s, __be32 *buffer,
+			      unsigned int data_blocks)
+{
+	struct amdtp_motu *p = s->protocol;
+	unsigned int channels, i, c;
+	u8 *byte;
+
+	channels = p->pcm_chunks;
+
+	for (i = 0; i < data_blocks; ++i) {
+		byte = (u8 *)buffer + p->pcm_byte_offset;
+
+		for (c = 0; c < channels; ++c) {
+			byte[0] = 0;
+			byte[1] = 0;
+			byte[2] = 0;
+			byte += 3;
+		}
+
+		buffer += s->data_block_quadlets;
+	}
+}
+
+int amdtp_motu_add_pcm_hw_constraints(struct amdtp_stream *s,
+				      struct snd_pcm_runtime *runtime)
+{
+	int err;
+
+	/* TODO: how to set an constraint for exactly 24bit PCM sample? */
+	err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
+	if (err < 0)
+		return err;
+
+	return amdtp_stream_add_pcm_hw_constraints(s, runtime);
+}
+
+void amdtp_motu_midi_trigger(struct amdtp_stream *s, unsigned int port,
+			     struct snd_rawmidi_substream *midi)
+{
+	struct amdtp_motu *p = s->protocol;
+
+	if (port < p->midi_ports)
+		WRITE_ONCE(p->midi, midi);
+}
+
+static void write_midi_messages(struct amdtp_stream *s, __be32 *buffer,
+				unsigned int data_blocks)
+{
+	struct amdtp_motu *p = s->protocol;
+	struct snd_rawmidi_substream *midi = READ_ONCE(p->midi);
+	u8 *b;
+	int i;
+
+	for (i = 0; i < data_blocks; i++) {
+		b = (u8 *)buffer;
+
+		if (midi && p->midi_db_count == 0 &&
+		    snd_rawmidi_transmit(midi, b + p->midi_byte_offset, 1) == 1) {
+			b[p->midi_flag_offset] = 0x01;
+		} else {
+			b[p->midi_byte_offset] = 0x00;
+			b[p->midi_flag_offset] = 0x00;
+		}
+
+		buffer += s->data_block_quadlets;
+
+		if (--p->midi_db_count < 0)
+			p->midi_db_count = p->midi_db_interval;
+	}
+}
+
+static void read_midi_messages(struct amdtp_stream *s, __be32 *buffer,
+			       unsigned int data_blocks)
+{
+	struct amdtp_motu *p = s->protocol;
+	struct snd_rawmidi_substream *midi;
+	u8 *b;
+	int i;
+
+	for (i = 0; i < data_blocks; i++) {
+		b = (u8 *)buffer;
+		midi = READ_ONCE(p->midi);
+
+		if (midi && (b[p->midi_flag_offset] & 0x01))
+			snd_rawmidi_receive(midi, b + p->midi_byte_offset, 1);
+
+		buffer += s->data_block_quadlets;
+	}
+}
+
+/* For tracepoints. */
+static void __maybe_unused copy_sph(u32 *frames, __be32 *buffer,
+				    unsigned int data_blocks,
+				    unsigned int data_block_quadlets)
+{
+	unsigned int i;
+
+	for (i = 0; i < data_blocks; ++i) {
+		*frames = be32_to_cpu(*buffer);
+		buffer += data_block_quadlets;
+		frames++;
+	}
+}
+
+/* For tracepoints. */
+static void __maybe_unused copy_message(u64 *frames, __be32 *buffer,
+					unsigned int data_blocks,
+					unsigned int data_block_quadlets)
+{
+	unsigned int i;
+
+	/* This is just for v2/v3 protocol. */
+	for (i = 0; i < data_blocks; ++i) {
+		*frames = be32_to_cpu(buffer[1]);
+		*frames <<= 16;
+		*frames |= be32_to_cpu(buffer[2]) >> 16;
+		++frames;
+		buffer += data_block_quadlets;
+	}
+}
+
+static void probe_tracepoints_events(struct amdtp_stream *s,
+				     const struct pkt_desc *descs,
+				     unsigned int packets)
+{
+	int i;
+
+	for (i = 0; i < packets; ++i) {
+		const struct pkt_desc *desc = descs + i;
+		__be32 *buf = desc->ctx_payload;
+		unsigned int data_blocks = desc->data_blocks;
+
+		trace_data_block_sph(s, data_blocks, buf);
+		trace_data_block_message(s, data_blocks, buf);
+	}
+}
+
+static void cache_event_offsets(struct amdtp_motu_cache *cache, const __be32 *buf,
+				unsigned int data_blocks, unsigned int data_block_quadlets)
+{
+	unsigned int *event_offsets = cache->event_offsets;
+	const unsigned int cache_size = cache->size;
+	unsigned int cache_tail = cache->tail;
+	unsigned int base_tick = cache->tx_cycle_count * TICKS_PER_CYCLE;
+	int i;
+
+	for (i = 0; i < data_blocks; ++i) {
+		u32 sph = be32_to_cpu(*buf);
+		unsigned int tick;
+
+		tick = ((sph & CIP_SPH_CYCLE_MASK) >> CIP_SPH_CYCLE_SHIFT) * TICKS_PER_CYCLE +
+		       (sph & CIP_SPH_OFFSET_MASK);
+
+		if (tick < base_tick)
+			tick += TICKS_PER_SECOND;
+		event_offsets[cache_tail] = tick - base_tick;
+
+		cache_tail = (cache_tail + 1) % cache_size;
+		buf += data_block_quadlets;
+	}
+
+	cache->tail = cache_tail;
+	cache->tx_cycle_count = (cache->tx_cycle_count + 1) % CYCLES_PER_SECOND;
+}
+
+static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
+					    const struct pkt_desc *descs,
+					    unsigned int packets,
+					    struct snd_pcm_substream *pcm)
+{
+	struct snd_motu *motu = container_of(s, struct snd_motu, tx_stream);
+	struct amdtp_motu *p = s->protocol;
+	unsigned int pcm_frames = 0;
+	int i;
+
+	if (p->cache->tx_cycle_count == UINT_MAX)
+		p->cache->tx_cycle_count = (s->domain->processing_cycle.tx_start % CYCLES_PER_SECOND);
+
+	// For data block processing.
+	for (i = 0; i < packets; ++i) {
+		const struct pkt_desc *desc = descs + i;
+		__be32 *buf = desc->ctx_payload;
+		unsigned int data_blocks = desc->data_blocks;
+
+		cache_event_offsets(p->cache, buf, data_blocks, s->data_block_quadlets);
+
+		if (pcm) {
+			read_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
+			pcm_frames += data_blocks;
+		}
+
+		if (p->midi_ports)
+			read_midi_messages(s, buf, data_blocks);
+	}
+
+	if (motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP) {
+		snd_motu_register_dsp_message_parser_parse(motu, descs, packets,
+							   s->data_block_quadlets);
+	} else if (motu->spec->flags & SND_MOTU_SPEC_COMMAND_DSP) {
+		snd_motu_command_dsp_message_parser_parse(motu, descs, packets,
+							  s->data_block_quadlets);
+	}
+
+	// For tracepoints.
+	if (trace_data_block_sph_enabled() ||
+	    trace_data_block_message_enabled())
+		probe_tracepoints_events(s, descs, packets);
+
+	return pcm_frames;
+}
+
+static void write_sph(struct amdtp_motu_cache *cache, __be32 *buffer, unsigned int data_blocks,
+		      unsigned int data_block_quadlets)
+{
+	unsigned int *event_offsets = cache->event_offsets;
+	const unsigned int cache_size = cache->size;
+	unsigned int cache_head = cache->head;
+	unsigned int base_tick = cache->rx_cycle_count * TICKS_PER_CYCLE;
+	int i;
+
+	for (i = 0; i < data_blocks; i++) {
+		unsigned int tick = (base_tick + event_offsets[cache_head]) % TICKS_PER_SECOND;
+		u32 sph = ((tick / TICKS_PER_CYCLE) << CIP_SPH_CYCLE_SHIFT) | (tick % TICKS_PER_CYCLE);
+		*buffer = cpu_to_be32(sph);
+
+		cache_head = (cache_head + 1) % cache_size;
+		buffer += data_block_quadlets;
+	}
+
+	cache->head = cache_head;
+	cache->rx_cycle_count = (cache->rx_cycle_count + 1) % CYCLES_PER_SECOND;
+}
+
+static unsigned int process_it_ctx_payloads(struct amdtp_stream *s,
+					    const struct pkt_desc *descs,
+					    unsigned int packets,
+					    struct snd_pcm_substream *pcm)
+{
+	struct amdtp_motu *p = s->protocol;
+	unsigned int pcm_frames = 0;
+	int i;
+
+	if (p->cache->rx_cycle_count == UINT_MAX)
+		p->cache->rx_cycle_count = (s->domain->processing_cycle.rx_start % CYCLES_PER_SECOND);
+
+	// For data block processing.
+	for (i = 0; i < packets; ++i) {
+		const struct pkt_desc *desc = descs + i;
+		__be32 *buf = desc->ctx_payload;
+		unsigned int data_blocks = desc->data_blocks;
+
+		if (pcm) {
+			write_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
+			pcm_frames += data_blocks;
+		} else {
+			write_pcm_silence(s, buf, data_blocks);
+		}
+
+		if (p->midi_ports)
+			write_midi_messages(s, buf, data_blocks);
+
+		write_sph(p->cache, buf, data_blocks, s->data_block_quadlets);
+	}
+
+	// For tracepoints.
+	if (trace_data_block_sph_enabled() ||
+	    trace_data_block_message_enabled())
+		probe_tracepoints_events(s, descs, packets);
+
+	return pcm_frames;
+}
+
+int amdtp_motu_init(struct amdtp_stream *s, struct fw_unit *unit,
+		    enum amdtp_stream_direction dir,
+		    const struct snd_motu_spec *spec, struct amdtp_motu_cache *cache)
+{
+	amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
+	int fmt = CIP_FMT_MOTU;
+	unsigned int flags = CIP_BLOCKING | CIP_UNAWARE_SYT;
+	struct amdtp_motu *p;
+	int err;
+
+	if (dir == AMDTP_IN_STREAM) {
+		process_ctx_payloads = process_ir_ctx_payloads;
+
+		/*
+		 * Units of version 3 transmits packets with invalid CIP header
+		 * against IEC 61883-1.
+		 */
+		if (spec->protocol_version == SND_MOTU_PROTOCOL_V3) {
+			flags |= CIP_WRONG_DBS |
+				 CIP_SKIP_DBC_ZERO_CHECK |
+				 CIP_HEADER_WITHOUT_EOH;
+			fmt = CIP_FMT_MOTU_TX_V3;
+		}
+
+		if (spec == &snd_motu_spec_8pre ||
+		    spec == &snd_motu_spec_ultralite) {
+			// 8pre has some quirks.
+			flags |= CIP_WRONG_DBS |
+				 CIP_SKIP_DBC_ZERO_CHECK;
+		}
+	} else {
+		process_ctx_payloads = process_it_ctx_payloads;
+		flags |= CIP_DBC_IS_END_EVENT;
+	}
+
+	err = amdtp_stream_init(s, unit, dir, flags, fmt, process_ctx_payloads,
+				sizeof(struct amdtp_motu));
+	if (err < 0)
+		return err;
+
+	s->sph = 1;
+
+	if (dir == AMDTP_OUT_STREAM) {
+		// Use fixed value for FDF field.
+		s->ctx_data.rx.fdf = MOTU_FDF_AM824;
+	}
+
+	p = s->protocol;
+	p->cache = cache;
+
+	return 0;
+}
diff --git a/sound/firewire/motu/motu-command-dsp-message-parser.c b/sound/firewire/motu/motu-command-dsp-message-parser.c
new file mode 100644
index 000000000..9efe4d364
--- /dev/null
+++ b/sound/firewire/motu/motu-command-dsp-message-parser.c
@@ -0,0 +1,181 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// motu-command-dsp-message-parser.c - a part of driver for MOTU FireWire series
+//
+// Copyright (c) 2021 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+
+// Below models allow software to configure their DSP function by command transferred in
+// asynchronous transaction:
+//  * 828 mk3 (FireWire only and Hybrid)
+//  * 896 mk3 (FireWire only and Hybrid)
+//  * Ultralite mk3 (FireWire only and Hybrid)
+//  * Traveler mk3
+//  * Track 16
+//
+// Isochronous packets from the above models includes messages to report state of hardware meter.
+
+#include "motu.h"
+
+enum msg_parser_state {
+	INITIALIZED,
+	FRAGMENT_DETECTED,
+	AVAILABLE,
+};
+
+struct msg_parser {
+	spinlock_t lock;
+	enum msg_parser_state state;
+	unsigned int interval;
+	unsigned int message_count;
+	unsigned int fragment_pos;
+	unsigned int value_index;
+	u64 value;
+	struct snd_firewire_motu_command_dsp_meter meter;
+};
+
+int snd_motu_command_dsp_message_parser_new(struct snd_motu *motu)
+{
+	struct msg_parser *parser;
+
+	parser = devm_kzalloc(&motu->card->card_dev, sizeof(*parser), GFP_KERNEL);
+	if (!parser)
+		return -ENOMEM;
+	spin_lock_init(&parser->lock);
+	motu->message_parser = parser;
+
+	return 0;
+}
+
+int snd_motu_command_dsp_message_parser_init(struct snd_motu *motu, enum cip_sfc sfc)
+{
+	struct msg_parser *parser = motu->message_parser;
+
+	parser->state = INITIALIZED;
+
+	// All of data blocks don't have messages with meaningful information.
+	switch (sfc) {
+	case CIP_SFC_176400:
+	case CIP_SFC_192000:
+		parser->interval = 4;
+		break;
+	case CIP_SFC_88200:
+	case CIP_SFC_96000:
+		parser->interval = 2;
+		break;
+	case CIP_SFC_32000:
+	case CIP_SFC_44100:
+	case CIP_SFC_48000:
+	default:
+		parser->interval = 1;
+		break;
+	}
+
+	return 0;
+}
+
+#define FRAGMENT_POS			6
+#define MIDI_BYTE_POS			7
+#define MIDI_FLAG_POS			8
+// One value of hardware meter consists of 4 messages.
+#define FRAGMENTS_PER_VALUE		4
+#define VALUES_AT_IMAGE_END		0xffffffffffffffff
+
+void snd_motu_command_dsp_message_parser_parse(struct snd_motu *motu, const struct pkt_desc *descs,
+					unsigned int desc_count, unsigned int data_block_quadlets)
+{
+	struct msg_parser *parser = motu->message_parser;
+	unsigned int interval = parser->interval;
+	unsigned long flags;
+	int i;
+
+	spin_lock_irqsave(&parser->lock, flags);
+
+	for (i = 0; i < desc_count; ++i) {
+		const struct pkt_desc *desc = descs + i;
+		__be32 *buffer = desc->ctx_payload;
+		unsigned int data_blocks = desc->data_blocks;
+		int j;
+
+		for (j = 0; j < data_blocks; ++j) {
+			u8 *b = (u8 *)buffer;
+			buffer += data_block_quadlets;
+
+			switch (parser->state) {
+			case INITIALIZED:
+			{
+				u8 fragment = b[FRAGMENT_POS];
+
+				if (fragment > 0) {
+					parser->value = fragment;
+					parser->message_count = 1;
+					parser->state = FRAGMENT_DETECTED;
+				}
+				break;
+			}
+			case FRAGMENT_DETECTED:
+			{
+				if (parser->message_count % interval == 0) {
+					u8 fragment = b[FRAGMENT_POS];
+
+					parser->value >>= 8;
+					parser->value |= (u64)fragment << 56;
+
+					if (parser->value == VALUES_AT_IMAGE_END) {
+						parser->state = AVAILABLE;
+						parser->fragment_pos = 0;
+						parser->value_index = 0;
+						parser->message_count = 0;
+					}
+				}
+				++parser->message_count;
+				break;
+			}
+			case AVAILABLE:
+			default:
+			{
+				if (parser->message_count % interval == 0) {
+					u8 fragment = b[FRAGMENT_POS];
+
+					parser->value >>= 8;
+					parser->value |= (u64)fragment << 56;
+					++parser->fragment_pos;
+
+					if (parser->fragment_pos == 4) {
+						// Skip the last two quadlets since they could be
+						// invalid value (0xffffffff) as floating point
+						// number.
+						if (parser->value_index <
+						    SNDRV_FIREWIRE_MOTU_COMMAND_DSP_METER_COUNT - 2) {
+							u32 val = (u32)(parser->value >> 32);
+							parser->meter.data[parser->value_index] = val;
+						}
+						++parser->value_index;
+						parser->fragment_pos = 0;
+					}
+
+					if (parser->value == VALUES_AT_IMAGE_END) {
+						parser->value_index = 0;
+						parser->fragment_pos = 0;
+						parser->message_count = 0;
+					}
+				}
+				++parser->message_count;
+				break;
+			}
+			}
+		}
+	}
+
+	spin_unlock_irqrestore(&parser->lock, flags);
+}
+
+void snd_motu_command_dsp_message_parser_copy_meter(struct snd_motu *motu,
+					struct snd_firewire_motu_command_dsp_meter *meter)
+{
+	struct msg_parser *parser = motu->message_parser;
+	unsigned long flags;
+
+	spin_lock_irqsave(&parser->lock, flags);
+	memcpy(meter, &parser->meter, sizeof(*meter));
+	spin_unlock_irqrestore(&parser->lock, flags);
+}
diff --git a/sound/firewire/motu/motu-hwdep.c b/sound/firewire/motu/motu-hwdep.c
new file mode 100644
index 000000000..88d1f4b56
--- /dev/null
+++ b/sound/firewire/motu/motu-hwdep.c
@@ -0,0 +1,302 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * motu-hwdep.c - a part of driver for MOTU FireWire series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ */
+
+/*
+ * This codes have five functionalities.
+ *
+ * 1.get information about firewire node
+ * 2.get notification about starting/stopping stream
+ * 3.lock/unlock streaming
+ *
+ */
+
+#include "motu.h"
+
+static bool has_dsp_event(struct snd_motu *motu)
+{
+	if (motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP)
+		return (snd_motu_register_dsp_message_parser_count_event(motu) > 0);
+	else
+		return false;
+}
+
+static long hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count,
+		       loff_t *offset)
+{
+	struct snd_motu *motu = hwdep->private_data;
+	DEFINE_WAIT(wait);
+	union snd_firewire_event event;
+
+	spin_lock_irq(&motu->lock);
+
+	while (!motu->dev_lock_changed && motu->msg == 0 && !has_dsp_event(motu)) {
+		prepare_to_wait(&motu->hwdep_wait, &wait, TASK_INTERRUPTIBLE);
+		spin_unlock_irq(&motu->lock);
+		schedule();
+		finish_wait(&motu->hwdep_wait, &wait);
+		if (signal_pending(current))
+			return -ERESTARTSYS;
+		spin_lock_irq(&motu->lock);
+	}
+
+	memset(&event, 0, sizeof(event));
+	if (motu->dev_lock_changed) {
+		event.lock_status.type = SNDRV_FIREWIRE_EVENT_LOCK_STATUS;
+		event.lock_status.status = (motu->dev_lock_count > 0);
+		motu->dev_lock_changed = false;
+		spin_unlock_irq(&motu->lock);
+
+		count = min_t(long, count, sizeof(event));
+		if (copy_to_user(buf, &event, count))
+			return -EFAULT;
+	} else if (motu->msg > 0) {
+		event.motu_notification.type = SNDRV_FIREWIRE_EVENT_MOTU_NOTIFICATION;
+		event.motu_notification.message = motu->msg;
+		motu->msg = 0;
+		spin_unlock_irq(&motu->lock);
+
+		count = min_t(long, count, sizeof(event));
+		if (copy_to_user(buf, &event, count))
+			return -EFAULT;
+	} else if (has_dsp_event(motu)) {
+		size_t consumed = 0;
+		u32 __user *ptr;
+		u32 ev;
+
+		spin_unlock_irq(&motu->lock);
+
+		// Header is filled later.
+		consumed += sizeof(event.motu_register_dsp_change);
+
+		while (consumed < count &&
+		       snd_motu_register_dsp_message_parser_copy_event(motu, &ev)) {
+			ptr = (u32 __user *)(buf + consumed);
+			if (put_user(ev, ptr))
+				return -EFAULT;
+			consumed += sizeof(ev);
+		}
+
+		event.motu_register_dsp_change.type = SNDRV_FIREWIRE_EVENT_MOTU_REGISTER_DSP_CHANGE;
+		event.motu_register_dsp_change.count =
+			(consumed - sizeof(event.motu_register_dsp_change)) / 4;
+		if (copy_to_user(buf, &event, sizeof(event.motu_register_dsp_change)))
+			return -EFAULT;
+
+		count = consumed;
+	} else {
+		spin_unlock_irq(&motu->lock);
+
+		count = 0;
+	}
+
+	return count;
+}
+
+static __poll_t hwdep_poll(struct snd_hwdep *hwdep, struct file *file,
+			       poll_table *wait)
+{
+	struct snd_motu *motu = hwdep->private_data;
+	__poll_t events;
+
+	poll_wait(file, &motu->hwdep_wait, wait);
+
+	spin_lock_irq(&motu->lock);
+	if (motu->dev_lock_changed || motu->msg || has_dsp_event(motu))
+		events = EPOLLIN | EPOLLRDNORM;
+	else
+		events = 0;
+	spin_unlock_irq(&motu->lock);
+
+	return events | EPOLLOUT;
+}
+
+static int hwdep_get_info(struct snd_motu *motu, void __user *arg)
+{
+	struct fw_device *dev = fw_parent_device(motu->unit);
+	struct snd_firewire_get_info info;
+
+	memset(&info, 0, sizeof(info));
+	info.type = SNDRV_FIREWIRE_TYPE_MOTU;
+	info.card = dev->card->index;
+	*(__be32 *)&info.guid[0] = cpu_to_be32(dev->config_rom[3]);
+	*(__be32 *)&info.guid[4] = cpu_to_be32(dev->config_rom[4]);
+	strscpy(info.device_name, dev_name(&dev->device),
+		sizeof(info.device_name));
+
+	if (copy_to_user(arg, &info, sizeof(info)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int hwdep_lock(struct snd_motu *motu)
+{
+	int err;
+
+	spin_lock_irq(&motu->lock);
+
+	if (motu->dev_lock_count == 0) {
+		motu->dev_lock_count = -1;
+		err = 0;
+	} else {
+		err = -EBUSY;
+	}
+
+	spin_unlock_irq(&motu->lock);
+
+	return err;
+}
+
+static int hwdep_unlock(struct snd_motu *motu)
+{
+	int err;
+
+	spin_lock_irq(&motu->lock);
+
+	if (motu->dev_lock_count == -1) {
+		motu->dev_lock_count = 0;
+		err = 0;
+	} else {
+		err = -EBADFD;
+	}
+
+	spin_unlock_irq(&motu->lock);
+
+	return err;
+}
+
+static int hwdep_release(struct snd_hwdep *hwdep, struct file *file)
+{
+	struct snd_motu *motu = hwdep->private_data;
+
+	spin_lock_irq(&motu->lock);
+	if (motu->dev_lock_count == -1)
+		motu->dev_lock_count = 0;
+	spin_unlock_irq(&motu->lock);
+
+	return 0;
+}
+
+static int hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file,
+	    unsigned int cmd, unsigned long arg)
+{
+	struct snd_motu *motu = hwdep->private_data;
+
+	switch (cmd) {
+	case SNDRV_FIREWIRE_IOCTL_GET_INFO:
+		return hwdep_get_info(motu, (void __user *)arg);
+	case SNDRV_FIREWIRE_IOCTL_LOCK:
+		return hwdep_lock(motu);
+	case SNDRV_FIREWIRE_IOCTL_UNLOCK:
+		return hwdep_unlock(motu);
+	case SNDRV_FIREWIRE_IOCTL_MOTU_REGISTER_DSP_METER:
+	{
+		struct snd_firewire_motu_register_dsp_meter *meter;
+		int err;
+
+		if (!(motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP))
+			return -ENXIO;
+
+		meter = kzalloc(sizeof(*meter), GFP_KERNEL);
+		if (!meter)
+			return -ENOMEM;
+
+		snd_motu_register_dsp_message_parser_copy_meter(motu, meter);
+
+		err = copy_to_user((void __user *)arg, meter, sizeof(*meter));
+		kfree(meter);
+
+		if (err)
+			return -EFAULT;
+
+		return 0;
+	}
+	case SNDRV_FIREWIRE_IOCTL_MOTU_COMMAND_DSP_METER:
+	{
+		struct snd_firewire_motu_command_dsp_meter *meter;
+		int err;
+
+		if (!(motu->spec->flags & SND_MOTU_SPEC_COMMAND_DSP))
+			return -ENXIO;
+
+		meter = kzalloc(sizeof(*meter), GFP_KERNEL);
+		if (!meter)
+			return -ENOMEM;
+
+		snd_motu_command_dsp_message_parser_copy_meter(motu, meter);
+
+		err = copy_to_user((void __user *)arg, meter, sizeof(*meter));
+		kfree(meter);
+
+		if (err)
+			return -EFAULT;
+
+		return 0;
+	}
+	case SNDRV_FIREWIRE_IOCTL_MOTU_REGISTER_DSP_PARAMETER:
+	{
+		struct snd_firewire_motu_register_dsp_parameter *param;
+		int err;
+
+		if (!(motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP))
+			return -ENXIO;
+
+		param = kzalloc(sizeof(*param), GFP_KERNEL);
+		if (!param)
+			return -ENOMEM;
+
+		snd_motu_register_dsp_message_parser_copy_parameter(motu, param);
+
+		err = copy_to_user((void __user *)arg, param, sizeof(*param));
+		kfree(param);
+		if (err)
+			return -EFAULT;
+
+		return 0;
+	}
+	default:
+		return -ENOIOCTLCMD;
+	}
+}
+
+#ifdef CONFIG_COMPAT
+static int hwdep_compat_ioctl(struct snd_hwdep *hwdep, struct file *file,
+			      unsigned int cmd, unsigned long arg)
+{
+	return hwdep_ioctl(hwdep, file, cmd,
+			   (unsigned long)compat_ptr(arg));
+}
+#else
+#define hwdep_compat_ioctl NULL
+#endif
+
+int snd_motu_create_hwdep_device(struct snd_motu *motu)
+{
+	static const struct snd_hwdep_ops ops = {
+		.read		= hwdep_read,
+		.release	= hwdep_release,
+		.poll		= hwdep_poll,
+		.ioctl		= hwdep_ioctl,
+		.ioctl_compat	= hwdep_compat_ioctl,
+	};
+	struct snd_hwdep *hwdep;
+	int err;
+
+	err = snd_hwdep_new(motu->card, motu->card->driver, 0, &hwdep);
+	if (err < 0)
+		return err;
+
+	strcpy(hwdep->name, "MOTU");
+	hwdep->iface = SNDRV_HWDEP_IFACE_FW_MOTU;
+	hwdep->ops = ops;
+	hwdep->private_data = motu;
+	hwdep->exclusive = true;
+
+	motu->hwdep = hwdep;
+
+	return 0;
+}
diff --git a/sound/firewire/motu/motu-midi.c b/sound/firewire/motu/motu-midi.c
new file mode 100644
index 000000000..2365f7dfd
--- /dev/null
+++ b/sound/firewire/motu/motu-midi.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * motu-midi.h - a part of driver for MOTU FireWire series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ */
+#include "motu.h"
+
+static int midi_open(struct snd_rawmidi_substream *substream)
+{
+	struct snd_motu *motu = substream->rmidi->private_data;
+	int err;
+
+	err = snd_motu_stream_lock_try(motu);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&motu->mutex);
+
+	err = snd_motu_stream_reserve_duplex(motu, 0, 0, 0);
+	if (err >= 0) {
+		++motu->substreams_counter;
+		err = snd_motu_stream_start_duplex(motu);
+		if (err < 0)
+			--motu->substreams_counter;
+	}
+
+	mutex_unlock(&motu->mutex);
+
+	if (err < 0)
+		snd_motu_stream_lock_release(motu);
+
+	return err;
+}
+
+static int midi_close(struct snd_rawmidi_substream *substream)
+{
+	struct snd_motu *motu = substream->rmidi->private_data;
+
+	mutex_lock(&motu->mutex);
+
+	--motu->substreams_counter;
+	snd_motu_stream_stop_duplex(motu);
+
+	mutex_unlock(&motu->mutex);
+
+	snd_motu_stream_lock_release(motu);
+	return 0;
+}
+
+static void midi_capture_trigger(struct snd_rawmidi_substream *substrm, int up)
+{
+	struct snd_motu *motu = substrm->rmidi->private_data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&motu->lock, flags);
+
+	if (up)
+		amdtp_motu_midi_trigger(&motu->tx_stream, substrm->number,
+					substrm);
+	else
+		amdtp_motu_midi_trigger(&motu->tx_stream, substrm->number,
+					NULL);
+
+	spin_unlock_irqrestore(&motu->lock, flags);
+}
+
+static void midi_playback_trigger(struct snd_rawmidi_substream *substrm, int up)
+{
+	struct snd_motu *motu = substrm->rmidi->private_data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&motu->lock, flags);
+
+	if (up)
+		amdtp_motu_midi_trigger(&motu->rx_stream, substrm->number,
+					substrm);
+	else
+		amdtp_motu_midi_trigger(&motu->rx_stream, substrm->number,
+					NULL);
+
+	spin_unlock_irqrestore(&motu->lock, flags);
+}
+
+static void set_midi_substream_names(struct snd_motu *motu,
+				     struct snd_rawmidi_str *str)
+{
+	struct snd_rawmidi_substream *subs;
+
+	list_for_each_entry(subs, &str->substreams, list) {
+		snprintf(subs->name, sizeof(subs->name),
+			 "%s MIDI %d", motu->card->shortname, subs->number + 1);
+	}
+}
+
+int snd_motu_create_midi_devices(struct snd_motu *motu)
+{
+	static const struct snd_rawmidi_ops capture_ops = {
+		.open		= midi_open,
+		.close		= midi_close,
+		.trigger	= midi_capture_trigger,
+	};
+	static const struct snd_rawmidi_ops playback_ops = {
+		.open		= midi_open,
+		.close		= midi_close,
+		.trigger	= midi_playback_trigger,
+	};
+	struct snd_rawmidi *rmidi;
+	struct snd_rawmidi_str *str;
+	int err;
+
+	/* create midi ports */
+	err = snd_rawmidi_new(motu->card, motu->card->driver, 0, 1, 1, &rmidi);
+	if (err < 0)
+		return err;
+
+	snprintf(rmidi->name, sizeof(rmidi->name),
+		 "%s MIDI", motu->card->shortname);
+	rmidi->private_data = motu;
+
+	rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT |
+			     SNDRV_RAWMIDI_INFO_OUTPUT |
+			     SNDRV_RAWMIDI_INFO_DUPLEX;
+
+	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
+			    &capture_ops);
+	str = &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT];
+	set_midi_substream_names(motu, str);
+
+	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
+			    &playback_ops);
+	str = &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT];
+	set_midi_substream_names(motu, str);
+
+	return 0;
+}
diff --git a/sound/firewire/motu/motu-pcm.c b/sound/firewire/motu/motu-pcm.c
new file mode 100644
index 000000000..d410c2efb
--- /dev/null
+++ b/sound/firewire/motu/motu-pcm.c
@@ -0,0 +1,370 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * motu-pcm.c - a part of driver for MOTU FireWire series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ */
+
+#include <sound/pcm_params.h>
+#include "motu.h"
+
+static int motu_rate_constraint(struct snd_pcm_hw_params *params,
+				struct snd_pcm_hw_rule *rule)
+{
+	struct snd_motu_packet_format *formats = rule->private;
+
+	const struct snd_interval *c =
+		hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_CHANNELS);
+	struct snd_interval *r =
+		hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
+	struct snd_interval rates = {
+		.min = UINT_MAX, .max = 0, .integer = 1
+	};
+	unsigned int i, pcm_channels, rate, mode;
+
+	for (i = 0; i < ARRAY_SIZE(snd_motu_clock_rates); ++i) {
+		rate = snd_motu_clock_rates[i];
+		mode = i / 2;
+
+		pcm_channels = formats->pcm_chunks[mode];
+		if (!snd_interval_test(c, pcm_channels))
+			continue;
+
+		rates.min = min(rates.min, rate);
+		rates.max = max(rates.max, rate);
+	}
+
+	return snd_interval_refine(r, &rates);
+}
+
+static int motu_channels_constraint(struct snd_pcm_hw_params *params,
+				    struct snd_pcm_hw_rule *rule)
+{
+	struct snd_motu_packet_format *formats = rule->private;
+
+	const struct snd_interval *r =
+		hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_RATE);
+	struct snd_interval *c =
+		hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
+	struct snd_interval channels = {
+		.min = UINT_MAX, .max = 0, .integer = 1
+	};
+	unsigned int i, pcm_channels, rate, mode;
+
+	for (i = 0; i < ARRAY_SIZE(snd_motu_clock_rates); ++i) {
+		rate = snd_motu_clock_rates[i];
+		mode = i / 2;
+
+		if (!snd_interval_test(r, rate))
+			continue;
+
+		pcm_channels = formats->pcm_chunks[mode];
+		channels.min = min(channels.min, pcm_channels);
+		channels.max = max(channels.max, pcm_channels);
+	}
+
+	return snd_interval_refine(c, &channels);
+}
+
+static void limit_channels_and_rates(struct snd_motu *motu,
+				     struct snd_pcm_runtime *runtime,
+				     struct snd_motu_packet_format *formats)
+{
+	struct snd_pcm_hardware *hw = &runtime->hw;
+	unsigned int i, pcm_channels, rate, mode;
+
+	hw->channels_min = UINT_MAX;
+	hw->channels_max = 0;
+
+	for (i = 0; i < ARRAY_SIZE(snd_motu_clock_rates); ++i) {
+		rate = snd_motu_clock_rates[i];
+		mode = i / 2;
+
+		pcm_channels = formats->pcm_chunks[mode];
+		if (pcm_channels == 0)
+			continue;
+
+		hw->rates |= snd_pcm_rate_to_rate_bit(rate);
+		hw->channels_min = min(hw->channels_min, pcm_channels);
+		hw->channels_max = max(hw->channels_max, pcm_channels);
+	}
+
+	snd_pcm_limit_hw_rates(runtime);
+}
+
+static int init_hw_info(struct snd_motu *motu,
+			struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct snd_pcm_hardware *hw = &runtime->hw;
+	struct amdtp_stream *stream;
+	struct snd_motu_packet_format *formats;
+	int err;
+
+	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
+		hw->formats = SNDRV_PCM_FMTBIT_S32;
+		stream = &motu->tx_stream;
+		formats = &motu->tx_packet_formats;
+	} else {
+		hw->formats = SNDRV_PCM_FMTBIT_S32;
+		stream = &motu->rx_stream;
+		formats = &motu->rx_packet_formats;
+	}
+
+	limit_channels_and_rates(motu, runtime, formats);
+
+	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
+				  motu_rate_constraint, formats,
+				  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
+	if (err < 0)
+		return err;
+	err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
+				  motu_channels_constraint, formats,
+				  SNDRV_PCM_HW_PARAM_RATE, -1);
+	if (err < 0)
+		return err;
+
+	return amdtp_motu_add_pcm_hw_constraints(stream, runtime);
+}
+
+static int pcm_open(struct snd_pcm_substream *substream)
+{
+	struct snd_motu *motu = substream->private_data;
+	struct amdtp_domain *d = &motu->domain;
+	enum snd_motu_clock_source src;
+	int err;
+
+	err = snd_motu_stream_lock_try(motu);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&motu->mutex);
+
+	err = snd_motu_stream_cache_packet_formats(motu);
+	if (err < 0)
+		goto err_locked;
+
+	err = init_hw_info(motu, substream);
+	if (err < 0)
+		goto err_locked;
+
+	err = snd_motu_protocol_get_clock_source(motu, &src);
+	if (err < 0)
+		goto err_locked;
+
+	// When source of clock is not internal or any stream is reserved for
+	// transmission of PCM frames, the available sampling rate is limited
+	// at current one.
+	if ((src != SND_MOTU_CLOCK_SOURCE_INTERNAL &&
+	     src != SND_MOTU_CLOCK_SOURCE_SPH) ||
+	    (motu->substreams_counter > 0 && d->events_per_period > 0)) {
+		unsigned int frames_per_period = d->events_per_period;
+		unsigned int frames_per_buffer = d->events_per_buffer;
+		unsigned int rate;
+
+		err = snd_motu_protocol_get_clock_rate(motu, &rate);
+		if (err < 0)
+			goto err_locked;
+
+		substream->runtime->hw.rate_min = rate;
+		substream->runtime->hw.rate_max = rate;
+
+		if (frames_per_period > 0) {
+			err = snd_pcm_hw_constraint_minmax(substream->runtime,
+					SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
+					frames_per_period, frames_per_period);
+			if (err < 0)
+				goto err_locked;
+
+			err = snd_pcm_hw_constraint_minmax(substream->runtime,
+					SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
+					frames_per_buffer, frames_per_buffer);
+			if (err < 0)
+				goto err_locked;
+		}
+	}
+
+	snd_pcm_set_sync(substream);
+
+	mutex_unlock(&motu->mutex);
+
+	return 0;
+err_locked:
+	mutex_unlock(&motu->mutex);
+	snd_motu_stream_lock_release(motu);
+	return err;
+}
+
+static int pcm_close(struct snd_pcm_substream *substream)
+{
+	struct snd_motu *motu = substream->private_data;
+
+	snd_motu_stream_lock_release(motu);
+
+	return 0;
+}
+
+static int pcm_hw_params(struct snd_pcm_substream *substream,
+			 struct snd_pcm_hw_params *hw_params)
+{
+	struct snd_motu *motu = substream->private_data;
+	int err = 0;
+
+	if (substream->runtime->state == SNDRV_PCM_STATE_OPEN) {
+		unsigned int rate = params_rate(hw_params);
+		unsigned int frames_per_period = params_period_size(hw_params);
+		unsigned int frames_per_buffer = params_buffer_size(hw_params);
+
+		mutex_lock(&motu->mutex);
+		err = snd_motu_stream_reserve_duplex(motu, rate,
+					frames_per_period, frames_per_buffer);
+		if (err >= 0)
+			++motu->substreams_counter;
+		mutex_unlock(&motu->mutex);
+	}
+
+	return err;
+}
+
+static int pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	struct snd_motu *motu = substream->private_data;
+
+	mutex_lock(&motu->mutex);
+
+	if (substream->runtime->state != SNDRV_PCM_STATE_OPEN)
+		--motu->substreams_counter;
+
+	snd_motu_stream_stop_duplex(motu);
+
+	mutex_unlock(&motu->mutex);
+
+	return 0;
+}
+
+static int capture_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_motu *motu = substream->private_data;
+	int err;
+
+	mutex_lock(&motu->mutex);
+	err = snd_motu_stream_start_duplex(motu);
+	mutex_unlock(&motu->mutex);
+	if (err >= 0)
+		amdtp_stream_pcm_prepare(&motu->tx_stream);
+
+	return 0;
+}
+static int playback_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_motu *motu = substream->private_data;
+	int err;
+
+	mutex_lock(&motu->mutex);
+	err = snd_motu_stream_start_duplex(motu);
+	mutex_unlock(&motu->mutex);
+	if (err >= 0)
+		amdtp_stream_pcm_prepare(&motu->rx_stream);
+
+	return err;
+}
+
+static int capture_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_motu *motu = substream->private_data;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		amdtp_stream_pcm_trigger(&motu->tx_stream, substream);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+		amdtp_stream_pcm_trigger(&motu->tx_stream, NULL);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+static int playback_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_motu *motu = substream->private_data;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		amdtp_stream_pcm_trigger(&motu->rx_stream, substream);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+		amdtp_stream_pcm_trigger(&motu->rx_stream, NULL);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static snd_pcm_uframes_t capture_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_motu *motu = substream->private_data;
+
+	return amdtp_domain_stream_pcm_pointer(&motu->domain, &motu->tx_stream);
+}
+static snd_pcm_uframes_t playback_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_motu *motu = substream->private_data;
+
+	return amdtp_domain_stream_pcm_pointer(&motu->domain, &motu->rx_stream);
+}
+
+static int capture_ack(struct snd_pcm_substream *substream)
+{
+	struct snd_motu *motu = substream->private_data;
+
+	return amdtp_domain_stream_pcm_ack(&motu->domain, &motu->tx_stream);
+}
+
+static int playback_ack(struct snd_pcm_substream *substream)
+{
+	struct snd_motu *motu = substream->private_data;
+
+	return amdtp_domain_stream_pcm_ack(&motu->domain, &motu->rx_stream);
+}
+
+int snd_motu_create_pcm_devices(struct snd_motu *motu)
+{
+	static const struct snd_pcm_ops capture_ops = {
+		.open      = pcm_open,
+		.close     = pcm_close,
+		.hw_params = pcm_hw_params,
+		.hw_free   = pcm_hw_free,
+		.prepare   = capture_prepare,
+		.trigger   = capture_trigger,
+		.pointer   = capture_pointer,
+		.ack       = capture_ack,
+	};
+	static const struct snd_pcm_ops playback_ops = {
+		.open      = pcm_open,
+		.close     = pcm_close,
+		.hw_params = pcm_hw_params,
+		.hw_free   = pcm_hw_free,
+		.prepare   = playback_prepare,
+		.trigger   = playback_trigger,
+		.pointer   = playback_pointer,
+		.ack       = playback_ack,
+	};
+	struct snd_pcm *pcm;
+	int err;
+
+	err = snd_pcm_new(motu->card, motu->card->driver, 0, 1, 1, &pcm);
+	if (err < 0)
+		return err;
+	pcm->private_data = motu;
+	strcpy(pcm->name, motu->card->shortname);
+
+	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &capture_ops);
+	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &playback_ops);
+	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC, NULL, 0, 0);
+
+	return 0;
+}
diff --git a/sound/firewire/motu/motu-proc.c b/sound/firewire/motu/motu-proc.c
new file mode 100644
index 000000000..f009cf7aa
--- /dev/null
+++ b/sound/firewire/motu/motu-proc.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * motu-proc.c - a part of driver for MOTU FireWire series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ */
+
+#include "./motu.h"
+
+static const char *const clock_names[] = {
+	[SND_MOTU_CLOCK_SOURCE_INTERNAL] = "Internal",
+	[SND_MOTU_CLOCK_SOURCE_ADAT_ON_DSUB] = "ADAT on Dsub-9pin interface",
+	[SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT] = "ADAT on optical interface",
+	[SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT_A] = "ADAT on optical interface A",
+	[SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT_B] = "ADAT on optical interface B",
+	[SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT] = "S/PDIF on optical interface",
+	[SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT_A] = "S/PDIF on optical interface A",
+	[SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT_B] = "S/PDIF on optical interface B",
+	[SND_MOTU_CLOCK_SOURCE_SPDIF_ON_COAX] = "S/PDIF on coaxial interface",
+	[SND_MOTU_CLOCK_SOURCE_AESEBU_ON_XLR] = "AESEBU on XLR interface",
+	[SND_MOTU_CLOCK_SOURCE_WORD_ON_BNC] = "Word clock on BNC interface",
+	[SND_MOTU_CLOCK_SOURCE_SPH] = "Source packet header",
+	[SND_MOTU_CLOCK_SOURCE_UNKNOWN] = "Unknown",
+};
+
+static void proc_read_clock(struct snd_info_entry *entry,
+			    struct snd_info_buffer *buffer)
+{
+
+	struct snd_motu *motu = entry->private_data;
+	unsigned int rate;
+	enum snd_motu_clock_source source;
+
+	if (snd_motu_protocol_get_clock_rate(motu, &rate) < 0)
+		return;
+	if (snd_motu_protocol_get_clock_source(motu, &source) < 0)
+		return;
+
+	snd_iprintf(buffer, "Rate:\t%d\n", rate);
+	snd_iprintf(buffer, "Source:\t%s\n", clock_names[source]);
+}
+
+static void proc_read_format(struct snd_info_entry *entry,
+			     struct snd_info_buffer *buffer)
+{
+	struct snd_motu *motu = entry->private_data;
+	unsigned int mode;
+	struct snd_motu_packet_format *formats;
+	int i;
+
+	if (snd_motu_protocol_cache_packet_formats(motu) < 0)
+		return;
+
+	snd_iprintf(buffer, "tx:\tmsg\tfixed\ttotal\n");
+	for (i = 0; i < SND_MOTU_CLOCK_RATE_COUNT; ++i) {
+		mode = i >> 1;
+
+		formats = &motu->tx_packet_formats;
+		snd_iprintf(buffer,
+			    "%u:\t%u\t%u\t%u\n",
+			    snd_motu_clock_rates[i],
+			    formats->msg_chunks,
+			    motu->spec->tx_fixed_pcm_chunks[mode],
+			    formats->pcm_chunks[mode]);
+	}
+
+	snd_iprintf(buffer, "rx:\tmsg\tfixed\ttotal\n");
+	for (i = 0; i < SND_MOTU_CLOCK_RATE_COUNT; ++i) {
+		mode = i >> 1;
+
+		formats = &motu->rx_packet_formats;
+		snd_iprintf(buffer,
+			    "%u:\t%u\t%u\t%u\n",
+			    snd_motu_clock_rates[i],
+			    formats->msg_chunks,
+			    motu->spec->rx_fixed_pcm_chunks[mode],
+			    formats->pcm_chunks[mode]);
+	}
+}
+
+static void add_node(struct snd_motu *motu, struct snd_info_entry *root,
+		     const char *name,
+		     void (*op)(struct snd_info_entry *e,
+				struct snd_info_buffer *b))
+{
+	struct snd_info_entry *entry;
+
+	entry = snd_info_create_card_entry(motu->card, name, root);
+	if (entry)
+		snd_info_set_text_ops(entry, motu, op);
+}
+
+void snd_motu_proc_init(struct snd_motu *motu)
+{
+	struct snd_info_entry *root;
+
+	/*
+	 * All nodes are automatically removed at snd_card_disconnect(),
+	 * by following to link list.
+	 */
+	root = snd_info_create_card_entry(motu->card, "firewire",
+					  motu->card->proc_root);
+	if (root == NULL)
+		return;
+	root->mode = S_IFDIR | 0555;
+
+	add_node(motu, root, "clock", proc_read_clock);
+	add_node(motu, root, "format", proc_read_format);
+}
diff --git a/sound/firewire/motu/motu-protocol-v1.c b/sound/firewire/motu/motu-protocol-v1.c
new file mode 100644
index 000000000..e811629f1
--- /dev/null
+++ b/sound/firewire/motu/motu-protocol-v1.c
@@ -0,0 +1,467 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// motu-protocol-v1.c - a part of driver for MOTU FireWire series
+//
+// Copyright (c) 2021 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+
+#include "motu.h"
+
+#include <linux/delay.h>
+
+// Status register for MOTU 828 (0x'ffff'f000'0b00).
+//
+// 0xffff0000: ISOC_COMM_CONTROL_MASK in motu-stream.c.
+// 0x00008000: mode of optical input interface.
+//   0x00008000: for S/PDIF signal.
+//   0x00000000: disabled or for ADAT signal.
+// 0x00004000: mode of optical output interface.
+//   0x00004000: for S/PDIF signal.
+//   0x00000000: disabled or for ADAT signal.
+// 0x00003f00: monitor input mode.
+//   0x00000800: analog-1/2
+//   0x00001a00: analog-3/4
+//   0x00002c00: analog-5/6
+//   0x00003e00: analog-7/8
+//   0x00000000: analog-1
+//   0x00000900: analog-2
+//   0x00001200: analog-3
+//   0x00001b00: analog-4
+//   0x00002400: analog-5
+//   0x00002d00: analog-6
+//   0x00003600: analog-7
+//   0x00003f00: analog-8
+// 0x00000080: enable stream input.
+// 0x00000040: disable monitor input.
+// 0x00000008: enable main out.
+// 0x00000004: rate of sampling clock.
+//   0x00000004: 48.0 kHz
+//   0x00000000: 44.1 kHz
+// 0x00000023: source of sampling clock.
+//   0x00000003: source packet header (SPH)
+//   0x00000002: S/PDIF on optical/coaxial interface.
+//   0x00000021: ADAT on optical interface
+//   0x00000001: ADAT on Dsub 9pin
+//   0x00000000: internal
+
+#define CLK_828_STATUS_OFFSET				0x0b00
+#define  CLK_828_STATUS_MASK				0x0000ffff
+#define  CLK_828_STATUS_FLAG_OPT_IN_IFACE_IS_SPDIF	0x00008000
+#define  CLK_828_STATUS_FLAG_OPT_OUT_IFACE_IS_SPDIF	0x00004000
+#define  CLK_828_STATUS_FLAG_FETCH_PCM_FRAMES		0x00000080
+#define  CLK_828_STATUS_FLAG_ENABLE_OUTPUT		0x00000008
+#define  CLK_828_STATUS_FLAG_RATE_48000			0x00000004
+#define  CLK_828_STATUS_MASK_SRC			0x00000023
+#define   CLK_828_STATUS_FLAG_SRC_ADAT_ON_OPT		0x00000021
+#define   CLK_828_STATUS_FLAG_SRC_SPH			0x00000003
+#define   CLK_828_STATUS_FLAG_SRC_SPDIF			0x00000002
+#define   CLK_828_STATUS_FLAG_SRC_ADAT_ON_DSUB		0x00000001
+#define   CLK_828_STATUS_FLAG_SRC_INTERNAL		0x00000000
+
+// Status register for MOTU 896 (0x'ffff'f000'0b14).
+//
+// 0xf0000000: enable physical and stream input to DAC.
+//   0x80000000: disable
+//   0x40000000: disable
+//   0x20000000: enable (prior to the other bits)
+//   0x10000000: disable
+//   0x00000000: disable
+// 0x08000000: speed of word clock signal output on BNC interface.
+//   0x00000000: force to low rate (44.1/48.0 kHz).
+//   0x08000000: follow to system clock.
+// 0x04000000: something relevant to clock.
+// 0x03000000: enable output.
+//  0x02000000: enabled irreversibly once standing unless the device voluntarily disables it.
+//  0x01000000: enabled irreversibly once standing unless the device voluntarily disables it.
+// 0x00ffff00: monitor input mode.
+//   0x00000000: disabled
+//   0x00004800: analog-1/2
+//   0x00005a00: analog-3/4
+//   0x00006c00: analog-5/6
+//   0x00007e00: analog-7/8
+//   0x00104800: AES/EBU-1/2
+//   0x00004000: analog-1
+//   0x00004900: analog-2
+//   0x00005200: analog-3
+//   0x00005b00: analog-4
+//   0x00006400: analog-5
+//   0x00006d00: analog-6
+//   0x00007600: analog-7
+//   0x00007f00: analog-8
+//   0x00104000: AES/EBU-1
+//   0x00104900: AES/EBU-2
+// 0x00000060: sample rate conversion for AES/EBU input/output.
+//   0x00000000: None
+//   0x00000020: input signal is converted to system rate
+//   0x00000040: output is slave to input, ignoring system rate
+//   0x00000060: output is double rate than system rate
+// 0x00000018: nominal rate of sampling clock.
+//   0x00000000: 44.1 kHz
+//   0x00000008: 48.0 kHz
+//   0x00000010: 88.2 kHz
+//   0x00000018: 96.0 kHz
+// 0x00000007: source of sampling clock.
+//   0x00000000: internal
+//   0x00000001: ADAT on optical interface
+//   0x00000002: AES/EBU on XLR
+//   0x00000003: source packet header (SPH)
+//   0x00000004: word clock on BNC
+//   0x00000005: ADAT on Dsub 9pin
+
+#define CLK_896_STATUS_OFFSET			0x0b14
+#define  CLK_896_STATUS_FLAG_FETCH_ENABLE	0x20000000
+#define  CLK_896_STATUS_FLAG_OUTPUT_ON		0x03000000
+#define  CLK_896_STATUS_MASK_SRC		0x00000007
+#define   CLK_896_STATUS_FLAG_SRC_INTERNAL	0x00000000
+#define   CLK_896_STATUS_FLAG_SRC_ADAT_ON_OPT	0x00000001
+#define   CLK_896_STATUS_FLAG_SRC_AESEBU	0x00000002
+#define   CLK_896_STATUS_FLAG_SRC_SPH		0x00000003
+#define   CLK_896_STATUS_FLAG_SRC_WORD		0x00000004
+#define   CLK_896_STATUS_FLAG_SRC_ADAT_ON_DSUB	0x00000005
+#define  CLK_896_STATUS_MASK_RATE		0x00000018
+#define   CLK_896_STATUS_FLAG_RATE_44100	0x00000000
+#define   CLK_896_STATUS_FLAG_RATE_48000	0x00000008
+#define   CLK_896_STATUS_FLAG_RATE_88200	0x00000010
+#define   CLK_896_STATUS_FLAG_RATE_96000	0x00000018
+
+static void parse_clock_rate_828(u32 data, unsigned int *rate)
+{
+	if (data & CLK_828_STATUS_FLAG_RATE_48000)
+		*rate = 48000;
+	else
+		*rate = 44100;
+}
+
+static int get_clock_rate_828(struct snd_motu *motu, unsigned int *rate)
+{
+	__be32 reg;
+	int err;
+
+	err = snd_motu_transaction_read(motu, CLK_828_STATUS_OFFSET, &reg, sizeof(reg));
+	if (err < 0)
+		return err;
+	parse_clock_rate_828(be32_to_cpu(reg), rate);
+
+	return 0;
+}
+
+static int parse_clock_rate_896(u32 data, unsigned int *rate)
+{
+	switch (data & CLK_896_STATUS_MASK_RATE) {
+	case CLK_896_STATUS_FLAG_RATE_44100:
+		*rate = 44100;
+		break;
+	case CLK_896_STATUS_FLAG_RATE_48000:
+		*rate = 48000;
+		break;
+	case CLK_896_STATUS_FLAG_RATE_88200:
+		*rate = 88200;
+		break;
+	case CLK_896_STATUS_FLAG_RATE_96000:
+		*rate = 96000;
+		break;
+	default:
+		return -ENXIO;
+	}
+
+	return 0;
+}
+
+static int get_clock_rate_896(struct snd_motu *motu, unsigned int *rate)
+{
+	__be32 reg;
+	int err;
+
+	err = snd_motu_transaction_read(motu, CLK_896_STATUS_OFFSET, &reg, sizeof(reg));
+	if (err < 0)
+		return err;
+	return parse_clock_rate_896(be32_to_cpu(reg), rate);
+}
+
+int snd_motu_protocol_v1_get_clock_rate(struct snd_motu *motu, unsigned int *rate)
+{
+	if (motu->spec == &snd_motu_spec_828)
+		return get_clock_rate_828(motu, rate);
+	else if (motu->spec == &snd_motu_spec_896)
+		return get_clock_rate_896(motu, rate);
+	else
+		return -ENXIO;
+}
+
+static int set_clock_rate_828(struct snd_motu *motu, unsigned int rate)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	err = snd_motu_transaction_read(motu, CLK_828_STATUS_OFFSET, &reg, sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg) & CLK_828_STATUS_MASK;
+
+	data &= ~CLK_828_STATUS_FLAG_RATE_48000;
+	if (rate == 48000)
+		data |= CLK_828_STATUS_FLAG_RATE_48000;
+
+	reg = cpu_to_be32(data);
+	return snd_motu_transaction_write(motu, CLK_828_STATUS_OFFSET, &reg, sizeof(reg));
+}
+
+static int set_clock_rate_896(struct snd_motu *motu, unsigned int rate)
+{
+	unsigned int flag;
+	__be32 reg;
+	u32 data;
+	int err;
+
+	err = snd_motu_transaction_read(motu, CLK_896_STATUS_OFFSET, &reg, sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg);
+
+	switch (rate) {
+	case 44100:
+		flag = CLK_896_STATUS_FLAG_RATE_44100;
+		break;
+	case 48000:
+		flag = CLK_896_STATUS_FLAG_RATE_48000;
+		break;
+	case 88200:
+		flag = CLK_896_STATUS_FLAG_RATE_88200;
+		break;
+	case 96000:
+		flag = CLK_896_STATUS_FLAG_RATE_96000;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	data &= ~CLK_896_STATUS_MASK_RATE;
+	data |= flag;
+
+	reg = cpu_to_be32(data);
+	return snd_motu_transaction_write(motu, CLK_896_STATUS_OFFSET, &reg, sizeof(reg));
+}
+
+int snd_motu_protocol_v1_set_clock_rate(struct snd_motu *motu, unsigned int rate)
+{
+	if (motu->spec == &snd_motu_spec_828)
+		return set_clock_rate_828(motu, rate);
+	else if (motu->spec == &snd_motu_spec_896)
+		return set_clock_rate_896(motu, rate);
+	else
+		return -ENXIO;
+}
+
+static int get_clock_source_828(struct snd_motu *motu, enum snd_motu_clock_source *src)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	err = snd_motu_transaction_read(motu, CLK_828_STATUS_OFFSET, &reg, sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg) & CLK_828_STATUS_MASK;
+
+	switch (data & CLK_828_STATUS_MASK_SRC) {
+	case CLK_828_STATUS_FLAG_SRC_ADAT_ON_OPT:
+		*src = SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT;
+		break;
+	case CLK_828_STATUS_FLAG_SRC_SPH:
+		*src = SND_MOTU_CLOCK_SOURCE_SPH;
+		break;
+	case CLK_828_STATUS_FLAG_SRC_SPDIF:
+	{
+		if (data & CLK_828_STATUS_FLAG_OPT_IN_IFACE_IS_SPDIF)
+			*src = SND_MOTU_CLOCK_SOURCE_SPDIF_ON_COAX;
+		else
+			*src = SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT;
+		break;
+	}
+	case CLK_828_STATUS_FLAG_SRC_ADAT_ON_DSUB:
+		*src = SND_MOTU_CLOCK_SOURCE_ADAT_ON_DSUB;
+		break;
+	case CLK_828_STATUS_FLAG_SRC_INTERNAL:
+		*src = SND_MOTU_CLOCK_SOURCE_INTERNAL;
+		break;
+	default:
+		return -ENXIO;
+	}
+
+	return 0;
+}
+
+static int get_clock_source_896(struct snd_motu *motu, enum snd_motu_clock_source *src)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	err = snd_motu_transaction_read(motu, CLK_896_STATUS_OFFSET, &reg, sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg);
+
+	switch (data & CLK_896_STATUS_MASK_SRC) {
+	case CLK_896_STATUS_FLAG_SRC_INTERNAL:
+		*src = SND_MOTU_CLOCK_SOURCE_INTERNAL;
+		break;
+	case CLK_896_STATUS_FLAG_SRC_ADAT_ON_OPT:
+		*src = SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT;
+		break;
+	case CLK_896_STATUS_FLAG_SRC_AESEBU:
+		*src = SND_MOTU_CLOCK_SOURCE_AESEBU_ON_XLR;
+		break;
+	case CLK_896_STATUS_FLAG_SRC_SPH:
+		*src = SND_MOTU_CLOCK_SOURCE_SPH;
+		break;
+	case CLK_896_STATUS_FLAG_SRC_WORD:
+		*src = SND_MOTU_CLOCK_SOURCE_WORD_ON_BNC;
+		break;
+	case CLK_896_STATUS_FLAG_SRC_ADAT_ON_DSUB:
+		*src = SND_MOTU_CLOCK_SOURCE_ADAT_ON_DSUB;
+		break;
+	default:
+		return -ENXIO;
+	}
+
+	return 0;
+}
+
+int snd_motu_protocol_v1_get_clock_source(struct snd_motu *motu, enum snd_motu_clock_source *src)
+{
+	if (motu->spec == &snd_motu_spec_828)
+		return get_clock_source_828(motu, src);
+	else if (motu->spec == &snd_motu_spec_896)
+		return get_clock_source_896(motu, src);
+	else
+		return -ENXIO;
+}
+
+static int switch_fetching_mode_828(struct snd_motu *motu, bool enable)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	err = snd_motu_transaction_read(motu, CLK_828_STATUS_OFFSET, &reg, sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg) & CLK_828_STATUS_MASK;
+
+	data &= ~(CLK_828_STATUS_FLAG_FETCH_PCM_FRAMES | CLK_828_STATUS_FLAG_ENABLE_OUTPUT);
+	if (enable) {
+		// This transaction should be initiated after the device receives batch of packets
+		// since the device voluntarily mutes outputs. As a workaround, yield processor over
+		// 100 msec.
+		msleep(100);
+		data |= CLK_828_STATUS_FLAG_FETCH_PCM_FRAMES | CLK_828_STATUS_FLAG_ENABLE_OUTPUT;
+	}
+
+	reg = cpu_to_be32(data);
+	return snd_motu_transaction_write(motu, CLK_828_STATUS_OFFSET, &reg, sizeof(reg));
+}
+
+static int switch_fetching_mode_896(struct snd_motu *motu, bool enable)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	err = snd_motu_transaction_read(motu, CLK_896_STATUS_OFFSET, &reg, sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg);
+
+	data &= ~CLK_896_STATUS_FLAG_FETCH_ENABLE;
+	if (enable)
+		data |= CLK_896_STATUS_FLAG_FETCH_ENABLE | CLK_896_STATUS_FLAG_OUTPUT_ON;
+
+	reg = cpu_to_be32(data);
+	return snd_motu_transaction_write(motu, CLK_896_STATUS_OFFSET, &reg, sizeof(reg));
+}
+
+int snd_motu_protocol_v1_switch_fetching_mode(struct snd_motu *motu, bool enable)
+{
+	if (motu->spec == &snd_motu_spec_828)
+		return switch_fetching_mode_828(motu, enable);
+	else if (motu->spec == &snd_motu_spec_896)
+		return switch_fetching_mode_896(motu, enable);
+	else
+		return -ENXIO;
+}
+
+static int detect_packet_formats_828(struct snd_motu *motu)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	motu->tx_packet_formats.pcm_byte_offset = 4;
+	motu->tx_packet_formats.msg_chunks = 2;
+
+	motu->rx_packet_formats.pcm_byte_offset = 4;
+	motu->rx_packet_formats.msg_chunks = 0;
+
+	err = snd_motu_transaction_read(motu, CLK_828_STATUS_OFFSET, &reg, sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg) & CLK_828_STATUS_MASK;
+
+	// The number of chunks is just reduced when SPDIF is activated.
+	if (!(data & CLK_828_STATUS_FLAG_OPT_IN_IFACE_IS_SPDIF))
+		motu->tx_packet_formats.pcm_chunks[0] += 8;
+
+	if (!(data & CLK_828_STATUS_FLAG_OPT_OUT_IFACE_IS_SPDIF))
+		motu->rx_packet_formats.pcm_chunks[0] += 8;
+
+	return 0;
+}
+
+static int detect_packet_formats_896(struct snd_motu *motu)
+{
+	// 24bit PCM frames follow to source packet header without message chunk.
+	motu->tx_packet_formats.pcm_byte_offset = 4;
+	motu->rx_packet_formats.pcm_byte_offset = 4;
+
+	// No message chunk in data block.
+	motu->tx_packet_formats.msg_chunks = 0;
+	motu->rx_packet_formats.msg_chunks = 0;
+
+	// Always enable optical interface for ADAT signal since the device have no registers
+	// to refer to current configuration.
+	motu->tx_packet_formats.pcm_chunks[0] += 8;
+	motu->tx_packet_formats.pcm_chunks[1] += 8;
+
+	motu->rx_packet_formats.pcm_chunks[0] += 8;
+	motu->rx_packet_formats.pcm_chunks[1] += 8;
+
+	return 0;
+}
+
+int snd_motu_protocol_v1_cache_packet_formats(struct snd_motu *motu)
+{
+	memcpy(motu->tx_packet_formats.pcm_chunks, motu->spec->tx_fixed_pcm_chunks,
+	       sizeof(motu->tx_packet_formats.pcm_chunks));
+	memcpy(motu->rx_packet_formats.pcm_chunks, motu->spec->rx_fixed_pcm_chunks,
+	       sizeof(motu->rx_packet_formats.pcm_chunks));
+
+	if (motu->spec == &snd_motu_spec_828)
+		return detect_packet_formats_828(motu);
+	else if (motu->spec == &snd_motu_spec_896)
+		return detect_packet_formats_896(motu);
+	else
+		return 0;
+}
+
+const struct snd_motu_spec snd_motu_spec_828 = {
+	.name = "828",
+	.protocol_version = SND_MOTU_PROTOCOL_V1,
+	.tx_fixed_pcm_chunks = {10, 0, 0},
+	.rx_fixed_pcm_chunks = {10, 0, 0},
+};
+
+const struct snd_motu_spec snd_motu_spec_896 = {
+	.name = "896",
+	.tx_fixed_pcm_chunks = {10, 10, 0},
+	.rx_fixed_pcm_chunks = {10, 10, 0},
+};
diff --git a/sound/firewire/motu/motu-protocol-v2.c b/sound/firewire/motu/motu-protocol-v2.c
new file mode 100644
index 000000000..a5f70efa2
--- /dev/null
+++ b/sound/firewire/motu/motu-protocol-v2.c
@@ -0,0 +1,321 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * motu-protocol-v2.c - a part of driver for MOTU FireWire series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ */
+
+#include "motu.h"
+
+#define V2_CLOCK_STATUS_OFFSET			0x0b14
+#define  V2_CLOCK_RATE_MASK			0x00000038
+#define  V2_CLOCK_RATE_SHIFT			3
+#define  V2_CLOCK_SRC_MASK			0x00000007
+#define  V2_CLOCK_SRC_SHIFT			0
+#define   V2_CLOCK_SRC_AESEBU_ON_XLR		0x07	// In Traveler.
+#define   V2_CLOCK_SRC_ADAT_ON_DSUB		0x05
+#define   V2_CLOCK_SRC_WORD_ON_BNC		0x04
+#define   V2_CLOCK_SRC_SPH			0x03
+#define   V2_CLOCK_SRC_SPDIF			0x02	// on either coaxial or optical. AES/EBU in 896HD.
+#define   V2_CLOCK_SRC_ADAT_ON_OPT		0x01
+#define   V2_CLOCK_SRC_INTERNAL			0x00
+#define  V2_CLOCK_FETCH_ENABLE			0x02000000
+#define  V2_CLOCK_MODEL_SPECIFIC		0x04000000
+
+#define V2_IN_OUT_CONF_OFFSET			0x0c04
+#define  V2_OPT_OUT_IFACE_MASK			0x00000c00
+#define  V2_OPT_OUT_IFACE_SHIFT			10
+#define  V2_OPT_IN_IFACE_MASK			0x00000300
+#define  V2_OPT_IN_IFACE_SHIFT			8
+#define  V2_OPT_IFACE_MODE_NONE			0
+#define  V2_OPT_IFACE_MODE_ADAT			1
+#define  V2_OPT_IFACE_MODE_SPDIF		2
+
+static int get_clock_rate(u32 data, unsigned int *rate)
+{
+	unsigned int index = (data & V2_CLOCK_RATE_MASK) >> V2_CLOCK_RATE_SHIFT;
+	if (index >= ARRAY_SIZE(snd_motu_clock_rates))
+		return -EIO;
+
+	*rate = snd_motu_clock_rates[index];
+
+	return 0;
+}
+
+int snd_motu_protocol_v2_get_clock_rate(struct snd_motu *motu,
+					unsigned int *rate)
+{
+	__be32 reg;
+	int err;
+
+	err = snd_motu_transaction_read(motu, V2_CLOCK_STATUS_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return err;
+
+	return get_clock_rate(be32_to_cpu(reg), rate);
+}
+
+int snd_motu_protocol_v2_set_clock_rate(struct snd_motu *motu,
+					unsigned int rate)
+{
+	__be32 reg;
+	u32 data;
+	int i;
+	int err;
+
+	for (i = 0; i < ARRAY_SIZE(snd_motu_clock_rates); ++i) {
+		if (snd_motu_clock_rates[i] == rate)
+			break;
+	}
+	if (i == ARRAY_SIZE(snd_motu_clock_rates))
+		return -EINVAL;
+
+	err = snd_motu_transaction_read(motu, V2_CLOCK_STATUS_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg);
+
+	data &= ~V2_CLOCK_RATE_MASK;
+	data |= i << V2_CLOCK_RATE_SHIFT;
+
+	reg = cpu_to_be32(data);
+	return snd_motu_transaction_write(motu, V2_CLOCK_STATUS_OFFSET, &reg,
+					  sizeof(reg));
+}
+
+static int get_clock_source(struct snd_motu *motu, u32 data,
+			    enum snd_motu_clock_source *src)
+{
+	switch (data & V2_CLOCK_SRC_MASK) {
+	case V2_CLOCK_SRC_INTERNAL:
+		*src = SND_MOTU_CLOCK_SOURCE_INTERNAL;
+		break;
+	case V2_CLOCK_SRC_ADAT_ON_OPT:
+		*src = SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT;
+		break;
+	case V2_CLOCK_SRC_SPDIF:
+	{
+		bool support_iec60958_on_opt = (motu->spec == &snd_motu_spec_828mk2 ||
+						motu->spec == &snd_motu_spec_traveler);
+
+		if (motu->spec == &snd_motu_spec_896hd) {
+			*src = SND_MOTU_CLOCK_SOURCE_AESEBU_ON_XLR;
+		} else if (!support_iec60958_on_opt) {
+			*src = SND_MOTU_CLOCK_SOURCE_SPDIF_ON_COAX;
+		} else {
+			__be32 reg;
+
+			// To check the configuration of optical interface.
+			int err = snd_motu_transaction_read(motu, V2_IN_OUT_CONF_OFFSET, &reg,
+							    sizeof(reg));
+			if (err < 0)
+				return err;
+
+			if (((data & V2_OPT_IN_IFACE_MASK) >> V2_OPT_IN_IFACE_SHIFT) ==
+			    V2_OPT_IFACE_MODE_SPDIF)
+				*src = SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT;
+			else
+				*src = SND_MOTU_CLOCK_SOURCE_SPDIF_ON_COAX;
+		}
+		break;
+	}
+	case V2_CLOCK_SRC_SPH:
+		*src = SND_MOTU_CLOCK_SOURCE_SPH;
+		break;
+	case V2_CLOCK_SRC_WORD_ON_BNC:
+		*src = SND_MOTU_CLOCK_SOURCE_WORD_ON_BNC;
+		break;
+	case V2_CLOCK_SRC_ADAT_ON_DSUB:
+		*src = SND_MOTU_CLOCK_SOURCE_ADAT_ON_DSUB;
+		break;
+	case V2_CLOCK_SRC_AESEBU_ON_XLR:
+		// For Traveler.
+		*src = SND_MOTU_CLOCK_SOURCE_AESEBU_ON_XLR;
+		break;
+	default:
+		*src = SND_MOTU_CLOCK_SOURCE_UNKNOWN;
+		break;
+	}
+
+	return 0;
+}
+
+int snd_motu_protocol_v2_get_clock_source(struct snd_motu *motu,
+					  enum snd_motu_clock_source *src)
+{
+	__be32 reg;
+	int err;
+
+	err = snd_motu_transaction_read(motu, V2_CLOCK_STATUS_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return err;
+
+	return get_clock_source(motu, be32_to_cpu(reg), src);
+}
+
+// Expected for Traveler, which implements Altera Cyclone EP1C3.
+static int switch_fetching_mode_cyclone(struct snd_motu *motu, u32 *data,
+					bool enable)
+{
+	*data |= V2_CLOCK_MODEL_SPECIFIC;
+
+	return 0;
+}
+
+// For UltraLite and 8pre, which implements Xilinx Spartan XC3S200.
+static int switch_fetching_mode_spartan(struct snd_motu *motu, u32 *data,
+					bool enable)
+{
+	unsigned int rate;
+	enum snd_motu_clock_source src;
+	int err;
+
+	err = get_clock_source(motu, *data, &src);
+	if (err < 0)
+		return err;
+
+	err = get_clock_rate(*data, &rate);
+	if (err < 0)
+		return err;
+
+	if (src == SND_MOTU_CLOCK_SOURCE_SPH && rate > 48000)
+		*data |= V2_CLOCK_MODEL_SPECIFIC;
+
+	return 0;
+}
+
+int snd_motu_protocol_v2_switch_fetching_mode(struct snd_motu *motu,
+					      bool enable)
+{
+	if (motu->spec == &snd_motu_spec_828mk2) {
+		// 828mkII implements Altera ACEX 1K EP1K30. Nothing to do.
+		return 0;
+	} else if (motu->spec == &snd_motu_spec_896hd) {
+		// 896HD implements Altera Cyclone EP1C3 but nothing to do.
+		return 0;
+	} else {
+		__be32 reg;
+		u32 data;
+		int err;
+
+		err = snd_motu_transaction_read(motu, V2_CLOCK_STATUS_OFFSET,
+						&reg, sizeof(reg));
+		if (err < 0)
+			return err;
+		data = be32_to_cpu(reg);
+
+		data &= ~(V2_CLOCK_FETCH_ENABLE | V2_CLOCK_MODEL_SPECIFIC);
+		if (enable)
+			data |= V2_CLOCK_FETCH_ENABLE;
+
+		if (motu->spec == &snd_motu_spec_traveler)
+			err = switch_fetching_mode_cyclone(motu, &data, enable);
+		else
+			err = switch_fetching_mode_spartan(motu, &data, enable);
+		if (err < 0)
+			return err;
+
+		reg = cpu_to_be32(data);
+		return snd_motu_transaction_write(motu, V2_CLOCK_STATUS_OFFSET,
+						  &reg, sizeof(reg));
+	}
+}
+
+int snd_motu_protocol_v2_cache_packet_formats(struct snd_motu *motu)
+{
+	bool has_two_opt_ifaces = (motu->spec == &snd_motu_spec_8pre);
+	__be32 reg;
+	u32 data;
+	int err;
+
+	motu->tx_packet_formats.pcm_byte_offset = 10;
+	motu->rx_packet_formats.pcm_byte_offset = 10;
+
+	motu->tx_packet_formats.msg_chunks = 2;
+	motu->rx_packet_formats.msg_chunks = 2;
+
+	err = snd_motu_transaction_read(motu, V2_IN_OUT_CONF_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg);
+
+	memcpy(motu->tx_packet_formats.pcm_chunks,
+	       motu->spec->tx_fixed_pcm_chunks,
+	       sizeof(motu->tx_packet_formats.pcm_chunks));
+	memcpy(motu->rx_packet_formats.pcm_chunks,
+	       motu->spec->rx_fixed_pcm_chunks,
+	       sizeof(motu->rx_packet_formats.pcm_chunks));
+
+	if (((data & V2_OPT_IN_IFACE_MASK) >> V2_OPT_IN_IFACE_SHIFT) == V2_OPT_IFACE_MODE_ADAT) {
+		motu->tx_packet_formats.pcm_chunks[0] += 8;
+
+		if (!has_two_opt_ifaces)
+			motu->tx_packet_formats.pcm_chunks[1] += 4;
+		else
+			motu->tx_packet_formats.pcm_chunks[1] += 8;
+	}
+
+	if (((data & V2_OPT_OUT_IFACE_MASK) >> V2_OPT_OUT_IFACE_SHIFT) == V2_OPT_IFACE_MODE_ADAT) {
+		motu->rx_packet_formats.pcm_chunks[0] += 8;
+
+		if (!has_two_opt_ifaces)
+			motu->rx_packet_formats.pcm_chunks[1] += 4;
+		else
+			motu->rx_packet_formats.pcm_chunks[1] += 8;
+	}
+
+	return 0;
+}
+
+const struct snd_motu_spec snd_motu_spec_828mk2 = {
+	.name = "828mk2",
+	.protocol_version = SND_MOTU_PROTOCOL_V2,
+	.flags = SND_MOTU_SPEC_RX_MIDI_2ND_Q |
+		 SND_MOTU_SPEC_TX_MIDI_2ND_Q |
+		 SND_MOTU_SPEC_REGISTER_DSP,
+	.tx_fixed_pcm_chunks = {14, 14, 0},
+	.rx_fixed_pcm_chunks = {14, 14, 0},
+};
+
+const struct snd_motu_spec snd_motu_spec_896hd = {
+	.name = "896HD",
+	.protocol_version = SND_MOTU_PROTOCOL_V2,
+	.flags = SND_MOTU_SPEC_REGISTER_DSP,
+	.tx_fixed_pcm_chunks = {14, 14, 8},
+	.rx_fixed_pcm_chunks = {14, 14, 8},
+};
+
+const struct snd_motu_spec snd_motu_spec_traveler = {
+	.name = "Traveler",
+	.protocol_version = SND_MOTU_PROTOCOL_V2,
+	.flags = SND_MOTU_SPEC_RX_MIDI_2ND_Q |
+		 SND_MOTU_SPEC_TX_MIDI_2ND_Q |
+		 SND_MOTU_SPEC_REGISTER_DSP,
+	.tx_fixed_pcm_chunks = {14, 14, 8},
+	.rx_fixed_pcm_chunks = {14, 14, 8},
+};
+
+const struct snd_motu_spec snd_motu_spec_ultralite = {
+	.name = "UltraLite",
+	.protocol_version = SND_MOTU_PROTOCOL_V2,
+	.flags = SND_MOTU_SPEC_RX_MIDI_2ND_Q |
+		 SND_MOTU_SPEC_TX_MIDI_2ND_Q |
+		 SND_MOTU_SPEC_REGISTER_DSP,
+	.tx_fixed_pcm_chunks = {14, 14, 0},
+	.rx_fixed_pcm_chunks = {14, 14, 0},
+};
+
+const struct snd_motu_spec snd_motu_spec_8pre = {
+	.name = "8pre",
+	.protocol_version = SND_MOTU_PROTOCOL_V2,
+	.flags = SND_MOTU_SPEC_RX_MIDI_2ND_Q |
+		 SND_MOTU_SPEC_TX_MIDI_2ND_Q |
+		 SND_MOTU_SPEC_REGISTER_DSP,
+	// Two dummy chunks always in the end of data block.
+	.tx_fixed_pcm_chunks = {10, 10, 0},
+	.rx_fixed_pcm_chunks = {6, 6, 0},
+};
diff --git a/sound/firewire/motu/motu-protocol-v3.c b/sound/firewire/motu/motu-protocol-v3.c
new file mode 100644
index 000000000..8a0426920
--- /dev/null
+++ b/sound/firewire/motu/motu-protocol-v3.c
@@ -0,0 +1,337 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * motu-protocol-v3.c - a part of driver for MOTU FireWire series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ */
+
+#include <linux/delay.h>
+#include "motu.h"
+
+#define V3_CLOCK_STATUS_OFFSET		0x0b14
+#define  V3_FETCH_PCM_FRAMES		0x02000000
+#define  V3_CLOCK_RATE_MASK		0x0000ff00
+#define  V3_CLOCK_RATE_SHIFT		8
+#define  V3_CLOCK_SOURCE_MASK		0x000000ff
+#define   V3_CLOCK_SRC_INTERNAL		0x00
+#define   V3_CLOCK_SRC_WORD_ON_BNC	0x01
+#define   V3_CLOCK_SRC_SPH		0x02
+#define   V3_CLOCK_SRC_AESEBU_ON_XLR	0x08
+#define   V3_CLOCK_SRC_SPDIF_ON_COAX	0x10
+#define   V3_CLOCK_SRC_OPT_IFACE_A	0x18
+#define   V3_CLOCK_SRC_OPT_IFACE_B	0x19
+
+#define V3_OPT_IFACE_MODE_OFFSET	0x0c94
+#define  V3_ENABLE_OPT_IN_IFACE_A	0x00000001
+#define  V3_ENABLE_OPT_IN_IFACE_B	0x00000002
+#define  V3_ENABLE_OPT_OUT_IFACE_A	0x00000100
+#define  V3_ENABLE_OPT_OUT_IFACE_B	0x00000200
+#define  V3_NO_ADAT_OPT_IN_IFACE_A	0x00010000
+#define  V3_NO_ADAT_OPT_IN_IFACE_B	0x00100000
+#define  V3_NO_ADAT_OPT_OUT_IFACE_A	0x00040000
+#define  V3_NO_ADAT_OPT_OUT_IFACE_B	0x00400000
+
+#define V3_MSG_FLAG_CLK_CHANGED		0x00000002
+#define V3_CLK_WAIT_MSEC		4000
+
+int snd_motu_protocol_v3_get_clock_rate(struct snd_motu *motu,
+					unsigned int *rate)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	err = snd_motu_transaction_read(motu, V3_CLOCK_STATUS_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg);
+
+	data = (data & V3_CLOCK_RATE_MASK) >> V3_CLOCK_RATE_SHIFT;
+	if (data >= ARRAY_SIZE(snd_motu_clock_rates))
+		return -EIO;
+
+	*rate = snd_motu_clock_rates[data];
+
+	return 0;
+}
+
+int snd_motu_protocol_v3_set_clock_rate(struct snd_motu *motu,
+					unsigned int rate)
+{
+	__be32 reg;
+	u32 data;
+	bool need_to_wait;
+	int i, err;
+
+	for (i = 0; i < ARRAY_SIZE(snd_motu_clock_rates); ++i) {
+		if (snd_motu_clock_rates[i] == rate)
+			break;
+	}
+	if (i == ARRAY_SIZE(snd_motu_clock_rates))
+		return -EINVAL;
+
+	err = snd_motu_transaction_read(motu, V3_CLOCK_STATUS_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg);
+
+	data &= ~(V3_CLOCK_RATE_MASK | V3_FETCH_PCM_FRAMES);
+	data |= i << V3_CLOCK_RATE_SHIFT;
+
+	need_to_wait = data != be32_to_cpu(reg);
+
+	reg = cpu_to_be32(data);
+	err = snd_motu_transaction_write(motu, V3_CLOCK_STATUS_OFFSET, &reg,
+					 sizeof(reg));
+	if (err < 0)
+		return err;
+
+	if (need_to_wait) {
+		int result;
+
+		motu->msg = 0;
+		result = wait_event_interruptible_timeout(motu->hwdep_wait,
+					motu->msg & V3_MSG_FLAG_CLK_CHANGED,
+					msecs_to_jiffies(V3_CLK_WAIT_MSEC));
+		if (result < 0)
+			return result;
+		if (result == 0)
+			return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+int snd_motu_protocol_v3_get_clock_source(struct snd_motu *motu,
+					  enum snd_motu_clock_source *src)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	err = snd_motu_transaction_read(motu, V3_CLOCK_STATUS_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg) & V3_CLOCK_SOURCE_MASK;
+
+	switch (data) {
+	case V3_CLOCK_SRC_INTERNAL:
+		*src = SND_MOTU_CLOCK_SOURCE_INTERNAL;
+		break;
+	case V3_CLOCK_SRC_WORD_ON_BNC:
+		*src = SND_MOTU_CLOCK_SOURCE_WORD_ON_BNC;
+		break;
+	case V3_CLOCK_SRC_SPH:
+		*src = SND_MOTU_CLOCK_SOURCE_SPH;
+		break;
+	case V3_CLOCK_SRC_AESEBU_ON_XLR:
+		*src = SND_MOTU_CLOCK_SOURCE_AESEBU_ON_XLR;
+		break;
+	case V3_CLOCK_SRC_SPDIF_ON_COAX:
+		*src = SND_MOTU_CLOCK_SOURCE_SPDIF_ON_COAX;
+		break;
+	case V3_CLOCK_SRC_OPT_IFACE_A:
+	case V3_CLOCK_SRC_OPT_IFACE_B:
+	{
+		__be32 reg;
+		u32 options;
+
+		err = snd_motu_transaction_read(motu,
+				V3_OPT_IFACE_MODE_OFFSET, &reg, sizeof(reg));
+		if (err < 0)
+			return err;
+		options = be32_to_cpu(reg);
+
+		if (data == V3_CLOCK_SRC_OPT_IFACE_A) {
+			if (options & V3_NO_ADAT_OPT_IN_IFACE_A)
+				*src = SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT_A;
+			else
+				*src = SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT_A;
+		} else {
+			if (options & V3_NO_ADAT_OPT_IN_IFACE_B)
+				*src = SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT_B;
+			else
+				*src = SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT_B;
+		}
+		break;
+	}
+	default:
+		*src = SND_MOTU_CLOCK_SOURCE_UNKNOWN;
+		break;
+	}
+
+	return 0;
+}
+
+int snd_motu_protocol_v3_switch_fetching_mode(struct snd_motu *motu,
+					      bool enable)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	err = snd_motu_transaction_read(motu, V3_CLOCK_STATUS_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return 0;
+	data = be32_to_cpu(reg);
+
+	if (enable)
+		data |= V3_FETCH_PCM_FRAMES;
+	else
+		data &= ~V3_FETCH_PCM_FRAMES;
+
+	reg = cpu_to_be32(data);
+	return snd_motu_transaction_write(motu, V3_CLOCK_STATUS_OFFSET, &reg,
+					  sizeof(reg));
+}
+
+static int detect_packet_formats_with_opt_ifaces(struct snd_motu *motu, u32 data)
+{
+	if (data & V3_ENABLE_OPT_IN_IFACE_A) {
+		if (data & V3_NO_ADAT_OPT_IN_IFACE_A) {
+			motu->tx_packet_formats.pcm_chunks[0] += 4;
+			motu->tx_packet_formats.pcm_chunks[1] += 4;
+		} else {
+			motu->tx_packet_formats.pcm_chunks[0] += 8;
+			motu->tx_packet_formats.pcm_chunks[1] += 4;
+		}
+	}
+
+	if (data & V3_ENABLE_OPT_IN_IFACE_B) {
+		if (data & V3_NO_ADAT_OPT_IN_IFACE_B) {
+			motu->tx_packet_formats.pcm_chunks[0] += 4;
+			motu->tx_packet_formats.pcm_chunks[1] += 4;
+		} else {
+			motu->tx_packet_formats.pcm_chunks[0] += 8;
+			motu->tx_packet_formats.pcm_chunks[1] += 4;
+		}
+	}
+
+	if (data & V3_ENABLE_OPT_OUT_IFACE_A) {
+		if (data & V3_NO_ADAT_OPT_OUT_IFACE_A) {
+			motu->rx_packet_formats.pcm_chunks[0] += 4;
+			motu->rx_packet_formats.pcm_chunks[1] += 4;
+		} else {
+			motu->rx_packet_formats.pcm_chunks[0] += 8;
+			motu->rx_packet_formats.pcm_chunks[1] += 4;
+		}
+	}
+
+	if (data & V3_ENABLE_OPT_OUT_IFACE_B) {
+		if (data & V3_NO_ADAT_OPT_OUT_IFACE_B) {
+			motu->rx_packet_formats.pcm_chunks[0] += 4;
+			motu->rx_packet_formats.pcm_chunks[1] += 4;
+		} else {
+			motu->rx_packet_formats.pcm_chunks[0] += 8;
+			motu->rx_packet_formats.pcm_chunks[1] += 4;
+		}
+	}
+
+	return 0;
+}
+
+int snd_motu_protocol_v3_cache_packet_formats(struct snd_motu *motu)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	motu->tx_packet_formats.pcm_byte_offset = 10;
+	motu->rx_packet_formats.pcm_byte_offset = 10;
+
+	motu->tx_packet_formats.msg_chunks = 2;
+	motu->rx_packet_formats.msg_chunks = 2;
+
+	err = snd_motu_transaction_read(motu, V3_OPT_IFACE_MODE_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg);
+
+	memcpy(motu->tx_packet_formats.pcm_chunks,
+	       motu->spec->tx_fixed_pcm_chunks,
+	       sizeof(motu->tx_packet_formats.pcm_chunks));
+	memcpy(motu->rx_packet_formats.pcm_chunks,
+	       motu->spec->rx_fixed_pcm_chunks,
+	       sizeof(motu->rx_packet_formats.pcm_chunks));
+
+	if (motu->spec == &snd_motu_spec_828mk3_fw ||
+	    motu->spec == &snd_motu_spec_828mk3_hybrid ||
+	    motu->spec == &snd_motu_spec_traveler_mk3 ||
+	    motu->spec == &snd_motu_spec_track16)
+		return detect_packet_formats_with_opt_ifaces(motu, data);
+	else
+		return 0;
+}
+
+const struct snd_motu_spec snd_motu_spec_828mk3_fw = {
+	.name = "828mk3",
+	.protocol_version = SND_MOTU_PROTOCOL_V3,
+	.flags = SND_MOTU_SPEC_RX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_TX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_COMMAND_DSP,
+	.tx_fixed_pcm_chunks = {18, 18, 14},
+	.rx_fixed_pcm_chunks = {14, 14, 10},
+};
+
+const struct snd_motu_spec snd_motu_spec_828mk3_hybrid = {
+	.name = "828mk3",
+	.protocol_version = SND_MOTU_PROTOCOL_V3,
+	.flags = SND_MOTU_SPEC_RX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_TX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_COMMAND_DSP,
+	.tx_fixed_pcm_chunks = {18, 18, 14},
+	.rx_fixed_pcm_chunks = {14, 14, 14},	// Additional 4 dummy chunks at higher rate.
+};
+
+const struct snd_motu_spec snd_motu_spec_traveler_mk3 = {
+	.name = "TravelerMk3",
+	.protocol_version = SND_MOTU_PROTOCOL_V3,
+	.flags = SND_MOTU_SPEC_RX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_TX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_COMMAND_DSP,
+	.tx_fixed_pcm_chunks = {18, 14, 10},
+	.rx_fixed_pcm_chunks = {14, 14, 10},
+};
+
+const struct snd_motu_spec snd_motu_spec_ultralite_mk3 = {
+	.name = "UltraLiteMk3",
+	.protocol_version = SND_MOTU_PROTOCOL_V3,
+	.flags = SND_MOTU_SPEC_RX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_TX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_COMMAND_DSP,
+	.tx_fixed_pcm_chunks = {18, 14, 10},
+	.rx_fixed_pcm_chunks = {14, 14, 14},
+};
+
+const struct snd_motu_spec snd_motu_spec_audio_express = {
+	.name = "AudioExpress",
+	.protocol_version = SND_MOTU_PROTOCOL_V3,
+	.flags = SND_MOTU_SPEC_RX_MIDI_2ND_Q |
+		 SND_MOTU_SPEC_TX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_REGISTER_DSP,
+	.tx_fixed_pcm_chunks = {10, 10, 0},
+	.rx_fixed_pcm_chunks = {10, 10, 0},
+};
+
+const struct snd_motu_spec snd_motu_spec_track16 = {
+	.name = "Track16",
+	.protocol_version = SND_MOTU_PROTOCOL_V3,
+	.flags = SND_MOTU_SPEC_RX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_TX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_COMMAND_DSP,
+	.tx_fixed_pcm_chunks = {14, 14, 14},
+	.rx_fixed_pcm_chunks = {6, 6, 6},
+};
+
+const struct snd_motu_spec snd_motu_spec_4pre = {
+	.name = "4pre",
+	.protocol_version = SND_MOTU_PROTOCOL_V3,
+	.flags = SND_MOTU_SPEC_REGISTER_DSP,
+	.tx_fixed_pcm_chunks = {10, 10, 0},
+	.rx_fixed_pcm_chunks = {10, 10, 0},
+};
diff --git a/sound/firewire/motu/motu-register-dsp-message-parser.c b/sound/firewire/motu/motu-register-dsp-message-parser.c
new file mode 100644
index 000000000..0c5875675
--- /dev/null
+++ b/sound/firewire/motu/motu-register-dsp-message-parser.c
@@ -0,0 +1,420 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// motu-register-dsp-message-parser.c - a part of driver for MOTU FireWire series
+//
+// Copyright (c) 2021 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+
+// Below models allow software to configure their DSP functions by asynchronous transaction
+// to access their internal registers.
+// * 828 mk2
+// * 896hd
+// * Traveler
+// * 8 pre
+// * Ultralite
+// * 4 pre
+// * Audio Express
+//
+// Additionally, isochronous packets from the above models include messages to notify state of
+// DSP. The messages are two set of 3 byte data in 2nd and 3rd quadlet of data block. When user
+// operates hardware components such as dial and switch, corresponding messages are transferred.
+// The messages include Hardware metering and MIDI messages as well.
+
+#include "motu.h"
+
+#define MSG_FLAG_POS                    4
+#define MSG_FLAG_TYPE_MASK              0xf8
+#define MSG_FLAG_MIDI_MASK              0x01
+#define MSG_FLAG_MODEL_SPECIFIC_MASK    0x06
+#define   MSG_FLAG_8PRE                 0x00
+#define   MSG_FLAG_ULTRALITE            0x04
+#define   MSG_FLAG_TRAVELER             0x04
+#define   MSG_FLAG_828MK2               0x04
+#define   MSG_FLAG_896HD                0x04
+#define   MSG_FLAG_4PRE                 0x05 // MIDI mask is in 8th byte.
+#define   MSG_FLAG_AUDIOEXPRESS         0x05 // MIDI mask is in 8th byte.
+#define MSG_FLAG_TYPE_SHIFT             3
+#define MSG_VALUE_POS                   5
+#define MSG_MIDI_BYTE_POS		6
+#define MSG_METER_IDX_POS               7
+
+// In 4 pre and Audio express, meter index is in 6th byte. MIDI flag is in 8th byte and MIDI byte
+// is in 7th byte.
+#define MSG_METER_IDX_POS_4PRE_AE	6
+#define MSG_MIDI_BYTE_POS_4PRE_AE	7
+#define MSG_FLAG_MIDI_POS_4PRE_AE	8
+
+enum register_dsp_msg_type {
+	// Used for messages with no information.
+	INVALID = 0x00,
+	MIXER_SELECT = 0x01,
+	MIXER_SRC_GAIN = 0x02,
+	MIXER_SRC_PAN = 0x03,
+	MIXER_SRC_FLAG = 0x04,
+	MIXER_OUTPUT_PAIRED_VOLUME = 0x05,
+	MIXER_OUTPUT_PAIRED_FLAG = 0x06,
+	MAIN_OUTPUT_PAIRED_VOLUME = 0x07,
+	HP_OUTPUT_PAIRED_VOLUME = 0x08,
+	HP_OUTPUT_PAIRED_ASSIGNMENT = 0x09,
+	// Transferred by all models but the purpose is still unknown.
+	UNKNOWN_0 = 0x0a,
+	// Specific to 828mk2, 896hd, Traveler.
+	UNKNOWN_2 = 0x0c,
+	// Specific to 828mk2, Traveler, and 896hd (not functional).
+	LINE_INPUT_BOOST = 0x0d,
+	// Specific to 828mk2, Traveler, and 896hd (not functional).
+	LINE_INPUT_NOMINAL_LEVEL = 0x0e,
+	// Specific to Ultralite, 4 pre, Audio express, and 8 pre (not functional).
+	INPUT_GAIN_AND_INVERT = 0x15,
+	// Specific to 4 pre, and Audio express.
+	INPUT_FLAG = 0x16,
+	// Specific to 4 pre, and Audio express.
+	MIXER_SRC_PAIRED_BALANCE = 0x17,
+	// Specific to 4 pre, and Audio express.
+	MIXER_SRC_PAIRED_WIDTH = 0x18,
+	// Transferred by all models. This type of message interposes the series of the other
+	// messages. The message delivers signal level up to 96.0 kHz. In 828mk2, 896hd, and
+	// Traveler, one of physical outputs is selected for the message. The selection is done
+	// by LSB one byte in asynchronous write quadlet transaction to 0x'ffff'f000'0b2c.
+	METER = 0x1f,
+};
+
+#define EVENT_QUEUE_SIZE	16
+
+struct msg_parser {
+	spinlock_t lock;
+	struct snd_firewire_motu_register_dsp_meter meter;
+	bool meter_pos_quirk;
+
+	struct snd_firewire_motu_register_dsp_parameter param;
+	u8 prev_mixer_src_type;
+	u8 mixer_ch;
+	u8 mixer_src_ch;
+
+	u8 input_ch;
+	u8 prev_msg_type;
+
+	u32 event_queue[EVENT_QUEUE_SIZE];
+	unsigned int push_pos;
+	unsigned int pull_pos;
+};
+
+int snd_motu_register_dsp_message_parser_new(struct snd_motu *motu)
+{
+	struct msg_parser *parser;
+	parser = devm_kzalloc(&motu->card->card_dev, sizeof(*parser), GFP_KERNEL);
+	if (!parser)
+		return -ENOMEM;
+	spin_lock_init(&parser->lock);
+	if (motu->spec == &snd_motu_spec_4pre || motu->spec == &snd_motu_spec_audio_express)
+		parser->meter_pos_quirk = true;
+	motu->message_parser = parser;
+	return 0;
+}
+
+int snd_motu_register_dsp_message_parser_init(struct snd_motu *motu)
+{
+	struct msg_parser *parser = motu->message_parser;
+
+	parser->prev_mixer_src_type = INVALID;
+	parser->mixer_ch = 0xff;
+	parser->mixer_src_ch = 0xff;
+	parser->prev_msg_type = INVALID;
+
+	return 0;
+}
+
+// Rough implementaion of queue without overrun check.
+static void queue_event(struct snd_motu *motu, u8 msg_type, u8 identifier0, u8 identifier1, u8 val)
+{
+	struct msg_parser *parser = motu->message_parser;
+	unsigned int pos = parser->push_pos;
+	u32 entry;
+
+	if (!motu->hwdep || motu->hwdep->used == 0)
+		return;
+
+	entry = (msg_type << 24) | (identifier0 << 16) | (identifier1 << 8) | val;
+	parser->event_queue[pos] = entry;
+
+	++pos;
+	if (pos >= EVENT_QUEUE_SIZE)
+		pos = 0;
+	parser->push_pos = pos;
+}
+
+void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const struct pkt_desc *descs,
+					unsigned int desc_count, unsigned int data_block_quadlets)
+{
+	struct msg_parser *parser = motu->message_parser;
+	bool meter_pos_quirk = parser->meter_pos_quirk;
+	unsigned int pos = parser->push_pos;
+	unsigned long flags;
+	int i;
+
+	spin_lock_irqsave(&parser->lock, flags);
+
+	for (i = 0; i < desc_count; ++i) {
+		const struct pkt_desc *desc = descs + i;
+		__be32 *buffer = desc->ctx_payload;
+		unsigned int data_blocks = desc->data_blocks;
+		int j;
+
+		for (j = 0; j < data_blocks; ++j) {
+			u8 *b = (u8 *)buffer;
+			u8 msg_type = (b[MSG_FLAG_POS] & MSG_FLAG_TYPE_MASK) >> MSG_FLAG_TYPE_SHIFT;
+			u8 val = b[MSG_VALUE_POS];
+
+			buffer += data_block_quadlets;
+
+			switch (msg_type) {
+			case MIXER_SELECT:
+			{
+				u8 mixer_ch = val / 0x20;
+				if (mixer_ch < SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT) {
+					parser->mixer_src_ch = 0;
+					parser->mixer_ch = mixer_ch;
+				}
+				break;
+			}
+			case MIXER_SRC_GAIN:
+			case MIXER_SRC_PAN:
+			case MIXER_SRC_FLAG:
+			case MIXER_SRC_PAIRED_BALANCE:
+			case MIXER_SRC_PAIRED_WIDTH:
+			{
+				struct snd_firewire_motu_register_dsp_parameter *param = &parser->param;
+				u8 mixer_ch = parser->mixer_ch;
+				u8 mixer_src_ch = parser->mixer_src_ch;
+
+				if (msg_type != parser->prev_mixer_src_type)
+					mixer_src_ch = 0;
+				else
+					++mixer_src_ch;
+				parser->prev_mixer_src_type = msg_type;
+
+				if (mixer_ch < SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT &&
+				    mixer_src_ch < SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT) {
+					u8 mixer_ch = parser->mixer_ch;
+
+					switch (msg_type) {
+					case MIXER_SRC_GAIN:
+						if (param->mixer.source[mixer_ch].gain[mixer_src_ch] != val) {
+							queue_event(motu, msg_type, mixer_ch, mixer_src_ch, val);
+							param->mixer.source[mixer_ch].gain[mixer_src_ch] = val;
+						}
+						break;
+					case MIXER_SRC_PAN:
+						if (param->mixer.source[mixer_ch].pan[mixer_src_ch] != val) {
+							queue_event(motu, msg_type, mixer_ch, mixer_src_ch, val);
+							param->mixer.source[mixer_ch].pan[mixer_src_ch] = val;
+						}
+						break;
+					case MIXER_SRC_FLAG:
+						if (param->mixer.source[mixer_ch].flag[mixer_src_ch] != val) {
+							queue_event(motu, msg_type, mixer_ch, mixer_src_ch, val);
+							param->mixer.source[mixer_ch].flag[mixer_src_ch] = val;
+						}
+						break;
+					case MIXER_SRC_PAIRED_BALANCE:
+						if (param->mixer.source[mixer_ch].paired_balance[mixer_src_ch] != val) {
+							queue_event(motu, msg_type, mixer_ch, mixer_src_ch, val);
+							param->mixer.source[mixer_ch].paired_balance[mixer_src_ch] = val;
+						}
+						break;
+					case MIXER_SRC_PAIRED_WIDTH:
+						if (param->mixer.source[mixer_ch].paired_width[mixer_src_ch] != val) {
+							queue_event(motu, msg_type, mixer_ch, mixer_src_ch, val);
+							param->mixer.source[mixer_ch].paired_width[mixer_src_ch] = val;
+						}
+						break;
+					default:
+						break;
+					}
+
+					parser->mixer_src_ch = mixer_src_ch;
+				}
+				break;
+			}
+			case MIXER_OUTPUT_PAIRED_VOLUME:
+			case MIXER_OUTPUT_PAIRED_FLAG:
+			{
+				struct snd_firewire_motu_register_dsp_parameter *param = &parser->param;
+				u8 mixer_ch = parser->mixer_ch;
+
+				if (mixer_ch < SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT) {
+					switch (msg_type) {
+					case MIXER_OUTPUT_PAIRED_VOLUME:
+						if (param->mixer.output.paired_volume[mixer_ch] != val) {
+							queue_event(motu, msg_type, mixer_ch, 0, val);
+							param->mixer.output.paired_volume[mixer_ch] = val;
+						}
+						break;
+					case MIXER_OUTPUT_PAIRED_FLAG:
+						if (param->mixer.output.paired_flag[mixer_ch] != val) {
+							queue_event(motu, msg_type, mixer_ch, 0, val);
+							param->mixer.output.paired_flag[mixer_ch] = val;
+						}
+						break;
+					default:
+						break;
+					}
+				}
+				break;
+			}
+			case MAIN_OUTPUT_PAIRED_VOLUME:
+				if (parser->param.output.main_paired_volume != val) {
+					queue_event(motu, msg_type, 0, 0, val);
+					parser->param.output.main_paired_volume = val;
+				}
+				break;
+			case HP_OUTPUT_PAIRED_VOLUME:
+				if (parser->param.output.hp_paired_volume != val) {
+					queue_event(motu, msg_type, 0, 0, val);
+					parser->param.output.hp_paired_volume = val;
+				}
+				break;
+			case HP_OUTPUT_PAIRED_ASSIGNMENT:
+				if (parser->param.output.hp_paired_assignment != val) {
+					queue_event(motu, msg_type, 0, 0, val);
+					parser->param.output.hp_paired_assignment = val;
+				}
+				break;
+			case LINE_INPUT_BOOST:
+				if (parser->param.line_input.boost_flag != val) {
+					queue_event(motu, msg_type, 0, 0, val);
+					parser->param.line_input.boost_flag = val;
+				}
+				break;
+			case LINE_INPUT_NOMINAL_LEVEL:
+				if (parser->param.line_input.nominal_level_flag != val) {
+					queue_event(motu, msg_type, 0, 0, val);
+					parser->param.line_input.nominal_level_flag = val;
+				}
+				break;
+			case INPUT_GAIN_AND_INVERT:
+			case INPUT_FLAG:
+			{
+				struct snd_firewire_motu_register_dsp_parameter *param = &parser->param;
+				u8 input_ch = parser->input_ch;
+
+				if (parser->prev_msg_type != msg_type)
+					input_ch = 0;
+				else
+					++input_ch;
+
+				if (input_ch < SNDRV_FIREWIRE_MOTU_REGISTER_DSP_INPUT_COUNT) {
+					switch (msg_type) {
+					case INPUT_GAIN_AND_INVERT:
+						if (param->input.gain_and_invert[input_ch] != val) {
+							queue_event(motu, msg_type, input_ch, 0, val);
+							param->input.gain_and_invert[input_ch] = val;
+						}
+						break;
+					case INPUT_FLAG:
+						if (param->input.flag[input_ch] != val) {
+							queue_event(motu, msg_type, input_ch, 0, val);
+							param->input.flag[input_ch] = val;
+						}
+						break;
+					default:
+						break;
+					}
+					parser->input_ch = input_ch;
+				}
+				break;
+			}
+			case UNKNOWN_0:
+			case UNKNOWN_2:
+				break;
+			case METER:
+			{
+				u8 pos;
+
+				if (!meter_pos_quirk)
+					pos = b[MSG_METER_IDX_POS];
+				else
+					pos = b[MSG_METER_IDX_POS_4PRE_AE];
+
+				if (pos < SNDRV_FIREWIRE_MOTU_REGISTER_DSP_METER_INPUT_COUNT) {
+					parser->meter.data[pos] = val;
+				} else if (pos >= 0x80) {
+					pos -= (0x80 - SNDRV_FIREWIRE_MOTU_REGISTER_DSP_METER_INPUT_COUNT);
+
+					if (pos < SNDRV_FIREWIRE_MOTU_REGISTER_DSP_METER_COUNT)
+						parser->meter.data[pos] = val;
+				}
+
+				// The message for meter is interruptible to the series of other
+				// types of messages. Don't cache it.
+				fallthrough;
+			}
+			case INVALID:
+			default:
+				// Don't cache it.
+				continue;
+			}
+
+			parser->prev_msg_type = msg_type;
+		}
+	}
+
+	if (pos != parser->push_pos)
+		wake_up(&motu->hwdep_wait);
+
+	spin_unlock_irqrestore(&parser->lock, flags);
+}
+
+void snd_motu_register_dsp_message_parser_copy_meter(struct snd_motu *motu,
+						struct snd_firewire_motu_register_dsp_meter *meter)
+{
+	struct msg_parser *parser = motu->message_parser;
+	unsigned long flags;
+
+	spin_lock_irqsave(&parser->lock, flags);
+	memcpy(meter, &parser->meter, sizeof(*meter));
+	spin_unlock_irqrestore(&parser->lock, flags);
+}
+
+void snd_motu_register_dsp_message_parser_copy_parameter(struct snd_motu *motu,
+					struct snd_firewire_motu_register_dsp_parameter *param)
+{
+	struct msg_parser *parser = motu->message_parser;
+	unsigned long flags;
+
+	spin_lock_irqsave(&parser->lock, flags);
+	memcpy(param, &parser->param, sizeof(*param));
+	spin_unlock_irqrestore(&parser->lock, flags);
+}
+
+unsigned int snd_motu_register_dsp_message_parser_count_event(struct snd_motu *motu)
+{
+	struct msg_parser *parser = motu->message_parser;
+
+	if (parser->pull_pos > parser->push_pos)
+		return EVENT_QUEUE_SIZE - parser->pull_pos + parser->push_pos;
+	else
+		return parser->push_pos - parser->pull_pos;
+}
+
+bool snd_motu_register_dsp_message_parser_copy_event(struct snd_motu *motu, u32 *event)
+{
+	struct msg_parser *parser = motu->message_parser;
+	unsigned int pos = parser->pull_pos;
+	unsigned long flags;
+
+	if (pos == parser->push_pos)
+		return false;
+
+	spin_lock_irqsave(&parser->lock, flags);
+
+	*event = parser->event_queue[pos];
+
+	++pos;
+	if (pos >= EVENT_QUEUE_SIZE)
+		pos = 0;
+	parser->pull_pos = pos;
+
+	spin_unlock_irqrestore(&parser->lock, flags);
+
+	return true;
+}
diff --git a/sound/firewire/motu/motu-stream.c b/sound/firewire/motu/motu-stream.c
new file mode 100644
index 000000000..64aec9c3e
--- /dev/null
+++ b/sound/firewire/motu/motu-stream.c
@@ -0,0 +1,438 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * motu-stream.c - a part of driver for MOTU FireWire series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ */
+
+#include "motu.h"
+
+#define	READY_TIMEOUT_MS	200
+
+#define ISOC_COMM_CONTROL_OFFSET		0x0b00
+#define  ISOC_COMM_CONTROL_MASK			0xffff0000
+#define  CHANGE_RX_ISOC_COMM_STATE		0x80000000
+#define  RX_ISOC_COMM_IS_ACTIVATED		0x40000000
+#define  RX_ISOC_COMM_CHANNEL_MASK		0x3f000000
+#define  RX_ISOC_COMM_CHANNEL_SHIFT		24
+#define  CHANGE_TX_ISOC_COMM_STATE		0x00800000
+#define  TX_ISOC_COMM_IS_ACTIVATED		0x00400000
+#define  TX_ISOC_COMM_CHANNEL_MASK		0x003f0000
+#define  TX_ISOC_COMM_CHANNEL_SHIFT		16
+
+#define PACKET_FORMAT_OFFSET			0x0b10
+#define  TX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS	0x00000080
+#define  RX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS	0x00000040
+#define  TX_PACKET_TRANSMISSION_SPEED_MASK	0x0000000f
+
+static int keep_resources(struct snd_motu *motu, unsigned int rate,
+			  struct amdtp_stream *stream)
+{
+	struct fw_iso_resources *resources;
+	struct snd_motu_packet_format *packet_format;
+	unsigned int midi_ports = 0;
+	int err;
+
+	if (stream == &motu->rx_stream) {
+		resources = &motu->rx_resources;
+		packet_format = &motu->rx_packet_formats;
+
+		if ((motu->spec->flags & SND_MOTU_SPEC_RX_MIDI_2ND_Q) ||
+		    (motu->spec->flags & SND_MOTU_SPEC_RX_MIDI_3RD_Q))
+			midi_ports = 1;
+	} else {
+		resources = &motu->tx_resources;
+		packet_format = &motu->tx_packet_formats;
+
+		if ((motu->spec->flags & SND_MOTU_SPEC_TX_MIDI_2ND_Q) ||
+		    (motu->spec->flags & SND_MOTU_SPEC_TX_MIDI_3RD_Q))
+			midi_ports = 1;
+	}
+
+	err = amdtp_motu_set_parameters(stream, rate, midi_ports,
+					packet_format);
+	if (err < 0)
+		return err;
+
+	return fw_iso_resources_allocate(resources,
+				amdtp_stream_get_max_payload(stream),
+				fw_parent_device(motu->unit)->max_speed);
+}
+
+static int begin_session(struct snd_motu *motu)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	// Configure the unit to start isochronous communication.
+	err = snd_motu_transaction_read(motu, ISOC_COMM_CONTROL_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg) & ~ISOC_COMM_CONTROL_MASK;
+
+	data |= CHANGE_RX_ISOC_COMM_STATE | RX_ISOC_COMM_IS_ACTIVATED |
+		(motu->rx_resources.channel << RX_ISOC_COMM_CHANNEL_SHIFT) |
+		CHANGE_TX_ISOC_COMM_STATE | TX_ISOC_COMM_IS_ACTIVATED |
+		(motu->tx_resources.channel << TX_ISOC_COMM_CHANNEL_SHIFT);
+
+	reg = cpu_to_be32(data);
+	return snd_motu_transaction_write(motu, ISOC_COMM_CONTROL_OFFSET, &reg,
+					  sizeof(reg));
+}
+
+static void finish_session(struct snd_motu *motu)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	err = snd_motu_protocol_switch_fetching_mode(motu, false);
+	if (err < 0)
+		return;
+
+	err = snd_motu_transaction_read(motu, ISOC_COMM_CONTROL_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return;
+	data = be32_to_cpu(reg);
+
+	data &= ~(RX_ISOC_COMM_IS_ACTIVATED | TX_ISOC_COMM_IS_ACTIVATED);
+	data |= CHANGE_RX_ISOC_COMM_STATE | CHANGE_TX_ISOC_COMM_STATE;
+
+	reg = cpu_to_be32(data);
+	snd_motu_transaction_write(motu, ISOC_COMM_CONTROL_OFFSET, &reg,
+				   sizeof(reg));
+}
+
+int snd_motu_stream_cache_packet_formats(struct snd_motu *motu)
+{
+	int err;
+
+	err = snd_motu_protocol_cache_packet_formats(motu);
+	if (err < 0)
+		return err;
+
+	if (motu->spec->flags & SND_MOTU_SPEC_TX_MIDI_2ND_Q) {
+		motu->tx_packet_formats.midi_flag_offset = 4;
+		motu->tx_packet_formats.midi_byte_offset = 6;
+	} else if (motu->spec->flags & SND_MOTU_SPEC_TX_MIDI_3RD_Q) {
+		motu->tx_packet_formats.midi_flag_offset = 8;
+		motu->tx_packet_formats.midi_byte_offset = 7;
+	}
+
+	if (motu->spec->flags & SND_MOTU_SPEC_RX_MIDI_2ND_Q) {
+		motu->rx_packet_formats.midi_flag_offset = 4;
+		motu->rx_packet_formats.midi_byte_offset = 6;
+	} else if (motu->spec->flags & SND_MOTU_SPEC_RX_MIDI_3RD_Q) {
+		motu->rx_packet_formats.midi_flag_offset = 8;
+		motu->rx_packet_formats.midi_byte_offset = 7;
+	}
+
+	return 0;
+}
+
+int snd_motu_stream_reserve_duplex(struct snd_motu *motu, unsigned int rate,
+				   unsigned int frames_per_period,
+				   unsigned int frames_per_buffer)
+{
+	unsigned int curr_rate;
+	int err;
+
+	err = snd_motu_protocol_get_clock_rate(motu, &curr_rate);
+	if (err < 0)
+		return err;
+	if (rate == 0)
+		rate = curr_rate;
+
+	if (motu->substreams_counter == 0 || curr_rate != rate) {
+		amdtp_domain_stop(&motu->domain);
+		finish_session(motu);
+
+		fw_iso_resources_free(&motu->tx_resources);
+		fw_iso_resources_free(&motu->rx_resources);
+
+		kfree(motu->cache.event_offsets);
+		motu->cache.event_offsets = NULL;
+
+		err = snd_motu_protocol_set_clock_rate(motu, rate);
+		if (err < 0) {
+			dev_err(&motu->unit->device,
+				"fail to set sampling rate: %d\n", err);
+			return err;
+		}
+
+		err = snd_motu_stream_cache_packet_formats(motu);
+		if (err < 0)
+			return err;
+
+		err = keep_resources(motu, rate, &motu->tx_stream);
+		if (err < 0)
+			return err;
+
+		err = keep_resources(motu, rate, &motu->rx_stream);
+		if (err < 0) {
+			fw_iso_resources_free(&motu->tx_resources);
+			return err;
+		}
+
+		err = amdtp_domain_set_events_per_period(&motu->domain,
+					frames_per_period, frames_per_buffer);
+		if (err < 0) {
+			fw_iso_resources_free(&motu->tx_resources);
+			fw_iso_resources_free(&motu->rx_resources);
+			return err;
+		}
+
+		motu->cache.size = motu->tx_stream.syt_interval * frames_per_buffer;
+		motu->cache.event_offsets = kcalloc(motu->cache.size, sizeof(*motu->cache.event_offsets),
+						  GFP_KERNEL);
+		if (!motu->cache.event_offsets) {
+			fw_iso_resources_free(&motu->tx_resources);
+			fw_iso_resources_free(&motu->rx_resources);
+			return -ENOMEM;
+		}
+	}
+
+	return 0;
+}
+
+static int ensure_packet_formats(struct snd_motu *motu)
+{
+	__be32 reg;
+	u32 data;
+	int err;
+
+	err = snd_motu_transaction_read(motu, PACKET_FORMAT_OFFSET, &reg,
+					sizeof(reg));
+	if (err < 0)
+		return err;
+	data = be32_to_cpu(reg);
+
+	data &= ~(TX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS |
+		  RX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS|
+		  TX_PACKET_TRANSMISSION_SPEED_MASK);
+	if (motu->spec->tx_fixed_pcm_chunks[0] == motu->tx_packet_formats.pcm_chunks[0])
+		data |= TX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS;
+	if (motu->spec->rx_fixed_pcm_chunks[0] == motu->rx_packet_formats.pcm_chunks[0])
+		data |= RX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS;
+	data |= fw_parent_device(motu->unit)->max_speed;
+
+	reg = cpu_to_be32(data);
+	return snd_motu_transaction_write(motu, PACKET_FORMAT_OFFSET, &reg,
+					  sizeof(reg));
+}
+
+int snd_motu_stream_start_duplex(struct snd_motu *motu)
+{
+	unsigned int generation = motu->rx_resources.generation;
+	int err = 0;
+
+	if (motu->substreams_counter == 0)
+		return 0;
+
+	if (amdtp_streaming_error(&motu->rx_stream) ||
+	    amdtp_streaming_error(&motu->tx_stream)) {
+		amdtp_domain_stop(&motu->domain);
+		finish_session(motu);
+	}
+
+	if (generation != fw_parent_device(motu->unit)->card->generation) {
+		err = fw_iso_resources_update(&motu->rx_resources);
+		if (err < 0)
+			return err;
+
+		err = fw_iso_resources_update(&motu->tx_resources);
+		if (err < 0)
+			return err;
+	}
+
+	if (!amdtp_stream_running(&motu->rx_stream)) {
+		int spd = fw_parent_device(motu->unit)->max_speed;
+
+		err = ensure_packet_formats(motu);
+		if (err < 0)
+			return err;
+
+		if (motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP) {
+			err = snd_motu_register_dsp_message_parser_init(motu);
+			if (err < 0)
+				return err;
+		} else if (motu->spec->flags & SND_MOTU_SPEC_COMMAND_DSP) {
+			err = snd_motu_command_dsp_message_parser_init(motu, motu->tx_stream.sfc);
+			if (err < 0)
+				return err;
+		}
+
+		err = begin_session(motu);
+		if (err < 0) {
+			dev_err(&motu->unit->device,
+				"fail to start isochronous comm: %d\n", err);
+			goto stop_streams;
+		}
+
+		err = amdtp_domain_add_stream(&motu->domain, &motu->tx_stream,
+					      motu->tx_resources.channel, spd);
+		if (err < 0)
+			goto stop_streams;
+
+		err = amdtp_domain_add_stream(&motu->domain, &motu->rx_stream,
+					      motu->rx_resources.channel, spd);
+		if (err < 0)
+			goto stop_streams;
+
+		motu->cache.tail = 0;
+		motu->cache.tx_cycle_count = UINT_MAX;
+		motu->cache.head = 0;
+		motu->cache.rx_cycle_count = UINT_MAX;
+
+		// NOTE: The device requires both of replay; the sequence of the number of data
+		// blocks per packet, and the sequence of source packet header per data block as
+		// presentation time.
+		err = amdtp_domain_start(&motu->domain, 0, true, false);
+		if (err < 0)
+			goto stop_streams;
+
+		if (!amdtp_domain_wait_ready(&motu->domain, READY_TIMEOUT_MS)) {
+			err = -ETIMEDOUT;
+			goto stop_streams;
+		}
+
+		err = snd_motu_protocol_switch_fetching_mode(motu, true);
+		if (err < 0) {
+			dev_err(&motu->unit->device,
+				"fail to enable frame fetching: %d\n", err);
+			goto stop_streams;
+		}
+	}
+
+	return 0;
+
+stop_streams:
+	amdtp_domain_stop(&motu->domain);
+	finish_session(motu);
+	return err;
+}
+
+void snd_motu_stream_stop_duplex(struct snd_motu *motu)
+{
+	if (motu->substreams_counter == 0) {
+		amdtp_domain_stop(&motu->domain);
+		finish_session(motu);
+
+		fw_iso_resources_free(&motu->tx_resources);
+		fw_iso_resources_free(&motu->rx_resources);
+
+		kfree(motu->cache.event_offsets);
+		motu->cache.event_offsets = NULL;
+	}
+}
+
+static int init_stream(struct snd_motu *motu, struct amdtp_stream *s)
+{
+	struct fw_iso_resources *resources;
+	enum amdtp_stream_direction dir;
+	int err;
+
+	if (s == &motu->tx_stream) {
+		resources = &motu->tx_resources;
+		dir = AMDTP_IN_STREAM;
+	} else {
+		resources = &motu->rx_resources;
+		dir = AMDTP_OUT_STREAM;
+	}
+
+	err = fw_iso_resources_init(resources, motu->unit);
+	if (err < 0)
+		return err;
+
+	err = amdtp_motu_init(s, motu->unit, dir, motu->spec, &motu->cache);
+	if (err < 0)
+		fw_iso_resources_destroy(resources);
+
+	return err;
+}
+
+static void destroy_stream(struct snd_motu *motu, struct amdtp_stream *s)
+{
+	amdtp_stream_destroy(s);
+
+	if (s == &motu->tx_stream)
+		fw_iso_resources_destroy(&motu->tx_resources);
+	else
+		fw_iso_resources_destroy(&motu->rx_resources);
+}
+
+int snd_motu_stream_init_duplex(struct snd_motu *motu)
+{
+	int err;
+
+	err = init_stream(motu, &motu->tx_stream);
+	if (err < 0)
+		return err;
+
+	err = init_stream(motu, &motu->rx_stream);
+	if (err < 0) {
+		destroy_stream(motu, &motu->tx_stream);
+		return err;
+	}
+
+	err = amdtp_domain_init(&motu->domain);
+	if (err < 0) {
+		destroy_stream(motu, &motu->tx_stream);
+		destroy_stream(motu, &motu->rx_stream);
+	}
+
+	return err;
+}
+
+// This function should be called before starting streams or after stopping
+// streams.
+void snd_motu_stream_destroy_duplex(struct snd_motu *motu)
+{
+	amdtp_domain_destroy(&motu->domain);
+
+	destroy_stream(motu, &motu->rx_stream);
+	destroy_stream(motu, &motu->tx_stream);
+
+	motu->substreams_counter = 0;
+}
+
+static void motu_lock_changed(struct snd_motu *motu)
+{
+	motu->dev_lock_changed = true;
+	wake_up(&motu->hwdep_wait);
+}
+
+int snd_motu_stream_lock_try(struct snd_motu *motu)
+{
+	int err;
+
+	spin_lock_irq(&motu->lock);
+
+	if (motu->dev_lock_count < 0) {
+		err = -EBUSY;
+		goto out;
+	}
+
+	if (motu->dev_lock_count++ == 0)
+		motu_lock_changed(motu);
+	err = 0;
+out:
+	spin_unlock_irq(&motu->lock);
+	return err;
+}
+
+void snd_motu_stream_lock_release(struct snd_motu *motu)
+{
+	spin_lock_irq(&motu->lock);
+
+	if (WARN_ON(motu->dev_lock_count <= 0))
+		goto out;
+
+	if (--motu->dev_lock_count == 0)
+		motu_lock_changed(motu);
+out:
+	spin_unlock_irq(&motu->lock);
+}
diff --git a/sound/firewire/motu/motu-transaction.c b/sound/firewire/motu/motu-transaction.c
new file mode 100644
index 000000000..2dc1d6e59
--- /dev/null
+++ b/sound/firewire/motu/motu-transaction.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * motu-transaction.c - a part of driver for MOTU FireWire series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ */
+
+
+#include "motu.h"
+
+#define SND_MOTU_ADDR_BASE	0xfffff0000000ULL
+#define ASYNC_ADDR_HI  0x0b04
+#define ASYNC_ADDR_LO  0x0b08
+
+int snd_motu_transaction_read(struct snd_motu *motu, u32 offset, __be32 *reg,
+			      size_t size)
+{
+	int tcode;
+
+	if (size % sizeof(__be32) > 0 || size <= 0)
+		return -EINVAL;
+	if (size == sizeof(__be32))
+		tcode = TCODE_READ_QUADLET_REQUEST;
+	else
+		tcode = TCODE_READ_BLOCK_REQUEST;
+
+	return snd_fw_transaction(motu->unit, tcode,
+				  SND_MOTU_ADDR_BASE + offset, reg, size, 0);
+}
+
+int snd_motu_transaction_write(struct snd_motu *motu, u32 offset, __be32 *reg,
+			       size_t size)
+{
+	int tcode;
+
+	if (size % sizeof(__be32) > 0 || size <= 0)
+		return -EINVAL;
+	if (size == sizeof(__be32))
+		tcode = TCODE_WRITE_QUADLET_REQUEST;
+	else
+		tcode = TCODE_WRITE_BLOCK_REQUEST;
+
+	return snd_fw_transaction(motu->unit, tcode,
+				  SND_MOTU_ADDR_BASE + offset, reg, size, 0);
+}
+
+static void handle_message(struct fw_card *card, struct fw_request *request,
+			   int tcode, int destination, int source,
+			   int generation, unsigned long long offset,
+			   void *data, size_t length, void *callback_data)
+{
+	struct snd_motu *motu = callback_data;
+	__be32 *buf = (__be32 *)data;
+	unsigned long flags;
+
+	if (tcode != TCODE_WRITE_QUADLET_REQUEST) {
+		fw_send_response(card, request, RCODE_COMPLETE);
+		return;
+	}
+
+	if (offset != motu->async_handler.offset || length != 4) {
+		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
+		return;
+	}
+
+	spin_lock_irqsave(&motu->lock, flags);
+	motu->msg = be32_to_cpu(*buf);
+	spin_unlock_irqrestore(&motu->lock, flags);
+
+	fw_send_response(card, request, RCODE_COMPLETE);
+
+	wake_up(&motu->hwdep_wait);
+}
+
+int snd_motu_transaction_reregister(struct snd_motu *motu)
+{
+	struct fw_device *device = fw_parent_device(motu->unit);
+	__be32 data;
+	int err;
+
+	if (motu->async_handler.callback_data == NULL)
+		return -EINVAL;
+
+	/* Register messaging address. Block transaction is not allowed. */
+	data = cpu_to_be32((device->card->node_id << 16) |
+			   (motu->async_handler.offset >> 32));
+	err = snd_motu_transaction_write(motu, ASYNC_ADDR_HI, &data,
+					 sizeof(data));
+	if (err < 0)
+		return err;
+
+	data = cpu_to_be32(motu->async_handler.offset);
+	return snd_motu_transaction_write(motu, ASYNC_ADDR_LO, &data,
+					  sizeof(data));
+}
+
+int snd_motu_transaction_register(struct snd_motu *motu)
+{
+	static const struct fw_address_region resp_register_region = {
+		.start	= 0xffffe0000000ull,
+		.end	= 0xffffe000ffffull,
+	};
+	int err;
+
+	/* Perhaps, 4 byte messages are transferred. */
+	motu->async_handler.length = 4;
+	motu->async_handler.address_callback = handle_message;
+	motu->async_handler.callback_data = motu;
+
+	err = fw_core_add_address_handler(&motu->async_handler,
+					  &resp_register_region);
+	if (err < 0)
+		return err;
+
+	err = snd_motu_transaction_reregister(motu);
+	if (err < 0) {
+		fw_core_remove_address_handler(&motu->async_handler);
+		motu->async_handler.address_callback = NULL;
+	}
+
+	return err;
+}
+
+void snd_motu_transaction_unregister(struct snd_motu *motu)
+{
+	__be32 data;
+
+	if (motu->async_handler.address_callback != NULL)
+		fw_core_remove_address_handler(&motu->async_handler);
+	motu->async_handler.address_callback = NULL;
+
+	/* Unregister the address. */
+	data = cpu_to_be32(0x00000000);
+	snd_motu_transaction_write(motu, ASYNC_ADDR_HI, &data, sizeof(data));
+	snd_motu_transaction_write(motu, ASYNC_ADDR_LO, &data, sizeof(data));
+}
diff --git a/sound/firewire/motu/motu.c b/sound/firewire/motu/motu.c
new file mode 100644
index 000000000..f8b7fe387
--- /dev/null
+++ b/sound/firewire/motu/motu.c
@@ -0,0 +1,205 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * motu.c - a part of driver for MOTU FireWire series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ */
+
+#include "motu.h"
+
+#define OUI_MOTU	0x0001f2
+
+MODULE_DESCRIPTION("MOTU FireWire driver");
+MODULE_AUTHOR("Takashi Sakamoto <o-takashi@sakamocchi.jp>");
+MODULE_LICENSE("GPL v2");
+
+const unsigned int snd_motu_clock_rates[SND_MOTU_CLOCK_RATE_COUNT] = {
+	/* mode 0 */
+	[0] =  44100,
+	[1] =  48000,
+	/* mode 1 */
+	[2] =  88200,
+	[3] =  96000,
+	/* mode 2 */
+	[4] = 176400,
+	[5] = 192000,
+};
+
+static void name_card(struct snd_motu *motu)
+{
+	struct fw_device *fw_dev = fw_parent_device(motu->unit);
+	struct fw_csr_iterator it;
+	int key, val;
+	u32 version = 0;
+
+	fw_csr_iterator_init(&it, motu->unit->directory);
+	while (fw_csr_iterator_next(&it, &key, &val)) {
+		switch (key) {
+		case CSR_MODEL:
+			version = val;
+			break;
+		}
+	}
+
+	strcpy(motu->card->driver, "FW-MOTU");
+	strcpy(motu->card->shortname, motu->spec->name);
+	strcpy(motu->card->mixername, motu->spec->name);
+	snprintf(motu->card->longname, sizeof(motu->card->longname),
+		 "MOTU %s (version:%06x), GUID %08x%08x at %s, S%d",
+		 motu->spec->name, version,
+		 fw_dev->config_rom[3], fw_dev->config_rom[4],
+		 dev_name(&motu->unit->device), 100 << fw_dev->max_speed);
+}
+
+static void motu_card_free(struct snd_card *card)
+{
+	struct snd_motu *motu = card->private_data;
+
+	snd_motu_transaction_unregister(motu);
+	snd_motu_stream_destroy_duplex(motu);
+
+	mutex_destroy(&motu->mutex);
+	fw_unit_put(motu->unit);
+}
+
+static int motu_probe(struct fw_unit *unit, const struct ieee1394_device_id *entry)
+{
+	struct snd_card *card;
+	struct snd_motu *motu;
+	int err;
+
+	err = snd_card_new(&unit->device, -1, NULL, THIS_MODULE, sizeof(*motu), &card);
+	if (err < 0)
+		return err;
+	card->private_free = motu_card_free;
+
+	motu = card->private_data;
+	motu->unit = fw_unit_get(unit);
+	dev_set_drvdata(&unit->device, motu);
+	motu->card = card;
+
+	motu->spec = (const struct snd_motu_spec *)entry->driver_data;
+	mutex_init(&motu->mutex);
+	spin_lock_init(&motu->lock);
+	init_waitqueue_head(&motu->hwdep_wait);
+
+	name_card(motu);
+
+	err = snd_motu_transaction_register(motu);
+	if (err < 0)
+		goto error;
+
+	err = snd_motu_stream_init_duplex(motu);
+	if (err < 0)
+		goto error;
+
+	snd_motu_proc_init(motu);
+
+	err = snd_motu_create_pcm_devices(motu);
+	if (err < 0)
+		goto error;
+
+	if ((motu->spec->flags & SND_MOTU_SPEC_RX_MIDI_2ND_Q) ||
+	    (motu->spec->flags & SND_MOTU_SPEC_RX_MIDI_3RD_Q) ||
+	    (motu->spec->flags & SND_MOTU_SPEC_TX_MIDI_2ND_Q) ||
+	    (motu->spec->flags & SND_MOTU_SPEC_TX_MIDI_3RD_Q)) {
+		err = snd_motu_create_midi_devices(motu);
+		if (err < 0)
+			goto error;
+	}
+
+	err = snd_motu_create_hwdep_device(motu);
+	if (err < 0)
+		goto error;
+
+	if (motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP) {
+		err = snd_motu_register_dsp_message_parser_new(motu);
+		if (err < 0)
+			goto error;
+	} else if (motu->spec->flags & SND_MOTU_SPEC_COMMAND_DSP) {
+		err = snd_motu_command_dsp_message_parser_new(motu);
+		if (err < 0)
+			goto error;
+	}
+
+	err = snd_card_register(card);
+	if (err < 0)
+		goto error;
+
+	return 0;
+error:
+	snd_card_free(card);
+	return err;
+}
+
+static void motu_remove(struct fw_unit *unit)
+{
+	struct snd_motu *motu = dev_get_drvdata(&unit->device);
+
+	// Block till all of ALSA character devices are released.
+	snd_card_free(motu->card);
+}
+
+static void motu_bus_update(struct fw_unit *unit)
+{
+	struct snd_motu *motu = dev_get_drvdata(&unit->device);
+
+	/* The handler address register becomes initialized. */
+	snd_motu_transaction_reregister(motu);
+}
+
+#define SND_MOTU_DEV_ENTRY(model, data)			\
+{							\
+	.match_flags	= IEEE1394_MATCH_VENDOR_ID |	\
+			  IEEE1394_MATCH_SPECIFIER_ID |	\
+			  IEEE1394_MATCH_VERSION,	\
+	.vendor_id	= OUI_MOTU,			\
+	.specifier_id	= OUI_MOTU,			\
+	.version	= model,			\
+	.driver_data	= (kernel_ulong_t)data,		\
+}
+
+static const struct ieee1394_device_id motu_id_table[] = {
+	SND_MOTU_DEV_ENTRY(0x000001, &snd_motu_spec_828),
+	SND_MOTU_DEV_ENTRY(0x000002, &snd_motu_spec_896),
+	SND_MOTU_DEV_ENTRY(0x000003, &snd_motu_spec_828mk2),
+	SND_MOTU_DEV_ENTRY(0x000005, &snd_motu_spec_896hd),
+	SND_MOTU_DEV_ENTRY(0x000009, &snd_motu_spec_traveler),
+	SND_MOTU_DEV_ENTRY(0x00000d, &snd_motu_spec_ultralite),
+	SND_MOTU_DEV_ENTRY(0x00000f, &snd_motu_spec_8pre),
+	SND_MOTU_DEV_ENTRY(0x000015, &snd_motu_spec_828mk3_fw), // FireWire only.
+	SND_MOTU_DEV_ENTRY(0x000019, &snd_motu_spec_ultralite_mk3), // FireWire only.
+	SND_MOTU_DEV_ENTRY(0x00001b, &snd_motu_spec_traveler_mk3),
+	SND_MOTU_DEV_ENTRY(0x000030, &snd_motu_spec_ultralite_mk3), // Hybrid.
+	SND_MOTU_DEV_ENTRY(0x000035, &snd_motu_spec_828mk3_hybrid), // Hybrid.
+	SND_MOTU_DEV_ENTRY(0x000033, &snd_motu_spec_audio_express),
+	SND_MOTU_DEV_ENTRY(0x000039, &snd_motu_spec_track16),
+	SND_MOTU_DEV_ENTRY(0x000045, &snd_motu_spec_4pre),
+	{ }
+};
+MODULE_DEVICE_TABLE(ieee1394, motu_id_table);
+
+static struct fw_driver motu_driver = {
+	.driver   = {
+		.owner	= THIS_MODULE,
+		.name	= KBUILD_MODNAME,
+		.bus	= &fw_bus_type,
+	},
+	.probe    = motu_probe,
+	.update   = motu_bus_update,
+	.remove   = motu_remove,
+	.id_table = motu_id_table,
+};
+
+static int __init alsa_motu_init(void)
+{
+	return driver_register(&motu_driver.driver);
+}
+
+static void __exit alsa_motu_exit(void)
+{
+	driver_unregister(&motu_driver.driver);
+}
+
+module_init(alsa_motu_init);
+module_exit(alsa_motu_exit);
diff --git a/sound/firewire/motu/motu.h b/sound/firewire/motu/motu.h
new file mode 100644
index 000000000..4189f2192
--- /dev/null
+++ b/sound/firewire/motu/motu.h
@@ -0,0 +1,298 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * motu.h - a part of driver for MOTU FireWire series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
+ */
+
+#ifndef SOUND_FIREWIRE_MOTU_H_INCLUDED
+#define SOUND_FIREWIRE_MOTU_H_INCLUDED
+
+#include <linux/device.h>
+#include <linux/firewire.h>
+#include <linux/firewire-constants.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/compat.h>
+#include <linux/sched/signal.h>
+
+#include <sound/control.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/info.h>
+#include <sound/rawmidi.h>
+#include <sound/firewire.h>
+#include <sound/hwdep.h>
+
+#include "../lib.h"
+#include "../amdtp-stream.h"
+#include "../iso-resources.h"
+
+struct snd_motu_packet_format {
+	unsigned char midi_flag_offset;
+	unsigned char midi_byte_offset;
+	unsigned char pcm_byte_offset;
+
+	unsigned char msg_chunks;
+	unsigned char pcm_chunks[3];
+};
+
+struct amdtp_motu_cache {
+	unsigned int *event_offsets;
+	unsigned int size;
+	unsigned int tail;
+	unsigned int tx_cycle_count;
+	unsigned int head;
+	unsigned int rx_cycle_count;
+};
+
+struct snd_motu {
+	struct snd_card *card;
+	struct fw_unit *unit;
+	struct mutex mutex;
+	spinlock_t lock;
+
+	/* Model dependent information. */
+	const struct snd_motu_spec *spec;
+
+	/* For packet streaming */
+	struct snd_motu_packet_format tx_packet_formats;
+	struct snd_motu_packet_format rx_packet_formats;
+	struct amdtp_stream tx_stream;
+	struct amdtp_stream rx_stream;
+	struct fw_iso_resources tx_resources;
+	struct fw_iso_resources rx_resources;
+	unsigned int substreams_counter;
+
+	/* For notification. */
+	struct fw_address_handler async_handler;
+	u32 msg;
+
+	/* For uapi */
+	int dev_lock_count;
+	bool dev_lock_changed;
+	wait_queue_head_t hwdep_wait;
+	struct snd_hwdep *hwdep;
+
+	struct amdtp_domain domain;
+
+	struct amdtp_motu_cache cache;
+
+	void *message_parser;
+};
+
+enum snd_motu_spec_flags {
+	SND_MOTU_SPEC_RX_MIDI_2ND_Q	= 0x0001,
+	SND_MOTU_SPEC_RX_MIDI_3RD_Q	= 0x0002,
+	SND_MOTU_SPEC_TX_MIDI_2ND_Q	= 0x0004,
+	SND_MOTU_SPEC_TX_MIDI_3RD_Q	= 0x0008,
+	SND_MOTU_SPEC_REGISTER_DSP	= 0x0010,
+	SND_MOTU_SPEC_COMMAND_DSP	= 0x0020,
+};
+
+#define SND_MOTU_CLOCK_RATE_COUNT	6
+extern const unsigned int snd_motu_clock_rates[SND_MOTU_CLOCK_RATE_COUNT];
+
+enum snd_motu_clock_source {
+	SND_MOTU_CLOCK_SOURCE_INTERNAL,
+	SND_MOTU_CLOCK_SOURCE_ADAT_ON_DSUB,
+	SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT,
+	SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT_A,
+	SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT_B,
+	SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT,
+	SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT_A,
+	SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT_B,
+	SND_MOTU_CLOCK_SOURCE_SPDIF_ON_COAX,
+	SND_MOTU_CLOCK_SOURCE_AESEBU_ON_XLR,
+	SND_MOTU_CLOCK_SOURCE_WORD_ON_BNC,
+	SND_MOTU_CLOCK_SOURCE_SPH,
+	SND_MOTU_CLOCK_SOURCE_UNKNOWN,
+};
+
+enum snd_motu_protocol_version {
+	SND_MOTU_PROTOCOL_V1,
+	SND_MOTU_PROTOCOL_V2,
+	SND_MOTU_PROTOCOL_V3,
+};
+
+struct snd_motu_spec {
+	const char *const name;
+	enum snd_motu_protocol_version protocol_version;
+	// The combination of snd_motu_spec_flags enumeration-constants.
+	unsigned int flags;
+
+	unsigned char tx_fixed_pcm_chunks[3];
+	unsigned char rx_fixed_pcm_chunks[3];
+};
+
+extern const struct snd_motu_spec snd_motu_spec_828;
+extern const struct snd_motu_spec snd_motu_spec_896;
+
+extern const struct snd_motu_spec snd_motu_spec_828mk2;
+extern const struct snd_motu_spec snd_motu_spec_896hd;
+extern const struct snd_motu_spec snd_motu_spec_traveler;
+extern const struct snd_motu_spec snd_motu_spec_ultralite;
+extern const struct snd_motu_spec snd_motu_spec_8pre;
+
+extern const struct snd_motu_spec snd_motu_spec_828mk3_fw;
+extern const struct snd_motu_spec snd_motu_spec_828mk3_hybrid;
+extern const struct snd_motu_spec snd_motu_spec_traveler_mk3;
+extern const struct snd_motu_spec snd_motu_spec_ultralite_mk3;
+extern const struct snd_motu_spec snd_motu_spec_audio_express;
+extern const struct snd_motu_spec snd_motu_spec_track16;
+extern const struct snd_motu_spec snd_motu_spec_4pre;
+
+int amdtp_motu_init(struct amdtp_stream *s, struct fw_unit *unit,
+		    enum amdtp_stream_direction dir,
+		    const struct snd_motu_spec *spec,
+		    struct amdtp_motu_cache *cache);
+int amdtp_motu_set_parameters(struct amdtp_stream *s, unsigned int rate,
+			      unsigned int midi_ports,
+			      struct snd_motu_packet_format *formats);
+int amdtp_motu_add_pcm_hw_constraints(struct amdtp_stream *s,
+				      struct snd_pcm_runtime *runtime);
+void amdtp_motu_midi_trigger(struct amdtp_stream *s, unsigned int port,
+			     struct snd_rawmidi_substream *midi);
+
+int snd_motu_transaction_read(struct snd_motu *motu, u32 offset, __be32 *reg,
+			      size_t size);
+int snd_motu_transaction_write(struct snd_motu *motu, u32 offset, __be32 *reg,
+			       size_t size);
+int snd_motu_transaction_register(struct snd_motu *motu);
+int snd_motu_transaction_reregister(struct snd_motu *motu);
+void snd_motu_transaction_unregister(struct snd_motu *motu);
+
+int snd_motu_stream_init_duplex(struct snd_motu *motu);
+void snd_motu_stream_destroy_duplex(struct snd_motu *motu);
+int snd_motu_stream_cache_packet_formats(struct snd_motu *motu);
+int snd_motu_stream_reserve_duplex(struct snd_motu *motu, unsigned int rate,
+				   unsigned int frames_per_period,
+				   unsigned int frames_per_buffer);
+int snd_motu_stream_start_duplex(struct snd_motu *motu);
+void snd_motu_stream_stop_duplex(struct snd_motu *motu);
+int snd_motu_stream_lock_try(struct snd_motu *motu);
+void snd_motu_stream_lock_release(struct snd_motu *motu);
+
+void snd_motu_proc_init(struct snd_motu *motu);
+
+int snd_motu_create_pcm_devices(struct snd_motu *motu);
+
+int snd_motu_create_midi_devices(struct snd_motu *motu);
+
+int snd_motu_create_hwdep_device(struct snd_motu *motu);
+
+int snd_motu_protocol_v1_get_clock_rate(struct snd_motu *motu,
+					unsigned int *rate);
+int snd_motu_protocol_v1_set_clock_rate(struct snd_motu *motu,
+					unsigned int rate);
+int snd_motu_protocol_v1_get_clock_source(struct snd_motu *motu,
+					  enum snd_motu_clock_source *src);
+int snd_motu_protocol_v1_switch_fetching_mode(struct snd_motu *motu,
+					      bool enable);
+int snd_motu_protocol_v1_cache_packet_formats(struct snd_motu *motu);
+
+int snd_motu_protocol_v2_get_clock_rate(struct snd_motu *motu,
+					unsigned int *rate);
+int snd_motu_protocol_v2_set_clock_rate(struct snd_motu *motu,
+					unsigned int rate);
+int snd_motu_protocol_v2_get_clock_source(struct snd_motu *motu,
+					  enum snd_motu_clock_source *src);
+int snd_motu_protocol_v2_switch_fetching_mode(struct snd_motu *motu,
+					      bool enable);
+int snd_motu_protocol_v2_cache_packet_formats(struct snd_motu *motu);
+
+int snd_motu_protocol_v3_get_clock_rate(struct snd_motu *motu,
+					unsigned int *rate);
+int snd_motu_protocol_v3_set_clock_rate(struct snd_motu *motu,
+					unsigned int rate);
+int snd_motu_protocol_v3_get_clock_source(struct snd_motu *motu,
+					  enum snd_motu_clock_source *src);
+int snd_motu_protocol_v3_switch_fetching_mode(struct snd_motu *motu,
+					      bool enable);
+int snd_motu_protocol_v3_cache_packet_formats(struct snd_motu *motu);
+
+static inline int snd_motu_protocol_get_clock_rate(struct snd_motu *motu,
+						   unsigned int *rate)
+{
+	if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V2)
+		return snd_motu_protocol_v2_get_clock_rate(motu, rate);
+	else if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V3)
+		return snd_motu_protocol_v3_get_clock_rate(motu, rate);
+	else if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V1)
+		return snd_motu_protocol_v1_get_clock_rate(motu, rate);
+	else
+		return -ENXIO;
+}
+
+static inline int snd_motu_protocol_set_clock_rate(struct snd_motu *motu,
+						   unsigned int rate)
+{
+	if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V2)
+		return snd_motu_protocol_v2_set_clock_rate(motu, rate);
+	else if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V3)
+		return snd_motu_protocol_v3_set_clock_rate(motu, rate);
+	else if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V1)
+		return snd_motu_protocol_v1_set_clock_rate(motu, rate);
+	else
+		return -ENXIO;
+}
+
+static inline int snd_motu_protocol_get_clock_source(struct snd_motu *motu,
+					enum snd_motu_clock_source *source)
+{
+	if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V2)
+		return snd_motu_protocol_v2_get_clock_source(motu, source);
+	else if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V3)
+		return snd_motu_protocol_v3_get_clock_source(motu, source);
+	else if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V1)
+		return snd_motu_protocol_v1_get_clock_source(motu, source);
+	else
+		return -ENXIO;
+}
+
+static inline int snd_motu_protocol_switch_fetching_mode(struct snd_motu *motu,
+							 bool enable)
+{
+	if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V2)
+		return snd_motu_protocol_v2_switch_fetching_mode(motu, enable);
+	else if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V3)
+		return snd_motu_protocol_v3_switch_fetching_mode(motu, enable);
+	else if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V1)
+		return snd_motu_protocol_v1_switch_fetching_mode(motu, enable);
+	else
+		return -ENXIO;
+}
+
+static inline int snd_motu_protocol_cache_packet_formats(struct snd_motu *motu)
+{
+	if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V2)
+		return snd_motu_protocol_v2_cache_packet_formats(motu);
+	else if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V3)
+		return snd_motu_protocol_v3_cache_packet_formats(motu);
+	else if (motu->spec->protocol_version == SND_MOTU_PROTOCOL_V1)
+		return snd_motu_protocol_v1_cache_packet_formats(motu);
+	else
+		return -ENXIO;
+}
+
+int snd_motu_register_dsp_message_parser_new(struct snd_motu *motu);
+int snd_motu_register_dsp_message_parser_init(struct snd_motu *motu);
+void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const struct pkt_desc *descs,
+					unsigned int desc_count, unsigned int data_block_quadlets);
+void snd_motu_register_dsp_message_parser_copy_meter(struct snd_motu *motu,
+					struct snd_firewire_motu_register_dsp_meter *meter);
+void snd_motu_register_dsp_message_parser_copy_parameter(struct snd_motu *motu,
+					struct snd_firewire_motu_register_dsp_parameter *params);
+unsigned int snd_motu_register_dsp_message_parser_count_event(struct snd_motu *motu);
+bool snd_motu_register_dsp_message_parser_copy_event(struct snd_motu *motu, u32 *event);
+
+int snd_motu_command_dsp_message_parser_new(struct snd_motu *motu);
+int snd_motu_command_dsp_message_parser_init(struct snd_motu *motu, enum cip_sfc sfc);
+void snd_motu_command_dsp_message_parser_parse(struct snd_motu *motu, const struct pkt_desc *descs,
+					unsigned int desc_count, unsigned int data_block_quadlets);
+void snd_motu_command_dsp_message_parser_copy_meter(struct snd_motu *motu,
+					struct snd_firewire_motu_command_dsp_meter *meter);
+
+#endif