2017-03-22 12:30:11 +00:00
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/*
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* motu.h - a part of driver for MOTU FireWire series
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*
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* Copyright (c) 2015-2017 Takashi Sakamoto <o-takashi@sakamocchi.jp>
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*
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* Licensed under the terms of the GNU General Public License, version 2.
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*/
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#ifndef SOUND_FIREWIRE_MOTU_H_INCLUDED
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#define SOUND_FIREWIRE_MOTU_H_INCLUDED
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#include <linux/device.h>
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#include <linux/firewire.h>
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#include <linux/firewire-constants.h>
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#include <linux/module.h>
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#include <linux/mod_devicetable.h>
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#include <linux/mutex.h>
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#include <linux/slab.h>
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#include <sound/control.h>
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#include <sound/core.h>
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ALSA: firewire-motu: add MOTU specific protocol layer
MOTU FireWire series uses blocking transmission for AMDTP packet streaming.
They transmit/receive 8,000 packets per second, to handle the same number
of data blocks as current sampling transmission frequency. Thus,
IEC 61883-1/6 packet streaming engine of ALSA firewire stack is available
for them.
However, the sequence of packet and data blocks includes some quirks.
Below sample is a sequence of CIP headers of packets received by 828mk2,
at 44.1kHz of sampling transmission frequency.
quads CIP1 CIP2
488 0x020F04E8 0x8222FFFF
8 0x020F04F8 0x8222FFFF
488 0x020F0400 0x8222FFFF
488 0x020F0408 0x8222FFFF
8 0x020F04E8 0x8222FFFF
488 0x020F04F0 0x8222FFFF
488 0x020F04F8 0x8222FFFF
The SID (source node ID), DBS (data block size), SPH (source packet header),
FMT (format ID), FDF (format dependent field) and SYT (time stamp) fields
are in IEC 61883-1. Especially, FMT is 0x02, FDF is 0x22 and SYT is 0xffff
to define MOTU specific protocol. In an aspect of dbc field, the value
represents accumulated number of data blocks included the packet. This
is against IEC 61883-1, because according to the specification this value
should be the number of data blocks already transferred.
In ALSA IEC 61883-1/6 engine, this quirk is already supported by
CIP_DBC_IS_END_EVENT flag, because Echo Audio Fireworks has.
Each data block includes SPH as its first quadlet field, to represent its
presentation time stamp. Actual value of SPH is compliant to IEC 61883-1;
lower 25 bits of 32 bits width consists of 13 bits cycle count and 12 bits
cycle offset.
The rest of each data block consists of 24 bit chunks. All of PCM samples,
MIDI messages, status and control messages are transferred by the chunks.
This is similar to '24-bit * 4 Audio Pack' in IEC 61883-6. The position of
each kind of data depends on generations of each model. The number of
whole chunks in a data block is a multiple of 4, to consists of
quadlet-aligned packets.
This commit adds data block processing layer specific for the MOTU
protocol. The remarkable point is the way to generate SPH header. Time
stamps for each data blocks are generated by below calculation:
* Using pre-computed table for the number of ticks per event
* 44,1kHz: (557 + 123/441)
* 48.0kHz: (512 + 0/441)
* 88.2kHz: (278 + 282/441)
* 96.0kHz: (256 + 0/441)
* 176.4kHz: (139 + 141/441)
* 192.0kHz: (128 + 0/441)
* Accumulate the ticks and set the value to SPH for every events.
* This way makes sense only for blocking transmission because this mode
transfers fixed number or none of events.
This calculation assumes that each data block has a PCM frame which is
sampled according to event timing clock. Current packet streaming layer
has the same assumption.
Although this sequence works fine for MOTU FireWire series at sampling
transmission frequency based on 48.0kHz, it is not enough at the frequency
based on 44.1kHz. The units generate choppy noise every few seconds.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-22 12:30:18 +00:00
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#include <sound/pcm.h>
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2017-03-22 12:30:11 +00:00
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2017-03-22 12:30:12 +00:00
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#include "../lib.h"
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ALSA: firewire-motu: add MOTU specific protocol layer
MOTU FireWire series uses blocking transmission for AMDTP packet streaming.
They transmit/receive 8,000 packets per second, to handle the same number
of data blocks as current sampling transmission frequency. Thus,
IEC 61883-1/6 packet streaming engine of ALSA firewire stack is available
for them.
However, the sequence of packet and data blocks includes some quirks.
Below sample is a sequence of CIP headers of packets received by 828mk2,
at 44.1kHz of sampling transmission frequency.
quads CIP1 CIP2
488 0x020F04E8 0x8222FFFF
8 0x020F04F8 0x8222FFFF
488 0x020F0400 0x8222FFFF
488 0x020F0408 0x8222FFFF
8 0x020F04E8 0x8222FFFF
488 0x020F04F0 0x8222FFFF
488 0x020F04F8 0x8222FFFF
The SID (source node ID), DBS (data block size), SPH (source packet header),
FMT (format ID), FDF (format dependent field) and SYT (time stamp) fields
are in IEC 61883-1. Especially, FMT is 0x02, FDF is 0x22 and SYT is 0xffff
to define MOTU specific protocol. In an aspect of dbc field, the value
represents accumulated number of data blocks included the packet. This
is against IEC 61883-1, because according to the specification this value
should be the number of data blocks already transferred.
In ALSA IEC 61883-1/6 engine, this quirk is already supported by
CIP_DBC_IS_END_EVENT flag, because Echo Audio Fireworks has.
Each data block includes SPH as its first quadlet field, to represent its
presentation time stamp. Actual value of SPH is compliant to IEC 61883-1;
lower 25 bits of 32 bits width consists of 13 bits cycle count and 12 bits
cycle offset.
The rest of each data block consists of 24 bit chunks. All of PCM samples,
MIDI messages, status and control messages are transferred by the chunks.
This is similar to '24-bit * 4 Audio Pack' in IEC 61883-6. The position of
each kind of data depends on generations of each model. The number of
whole chunks in a data block is a multiple of 4, to consists of
quadlet-aligned packets.
This commit adds data block processing layer specific for the MOTU
protocol. The remarkable point is the way to generate SPH header. Time
stamps for each data blocks are generated by below calculation:
* Using pre-computed table for the number of ticks per event
* 44,1kHz: (557 + 123/441)
* 48.0kHz: (512 + 0/441)
* 88.2kHz: (278 + 282/441)
* 96.0kHz: (256 + 0/441)
* 176.4kHz: (139 + 141/441)
* 192.0kHz: (128 + 0/441)
* Accumulate the ticks and set the value to SPH for every events.
* This way makes sense only for blocking transmission because this mode
transfers fixed number or none of events.
This calculation assumes that each data block has a PCM frame which is
sampled according to event timing clock. Current packet streaming layer
has the same assumption.
Although this sequence works fine for MOTU FireWire series at sampling
transmission frequency based on 48.0kHz, it is not enough at the frequency
based on 44.1kHz. The units generate choppy noise every few seconds.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-22 12:30:18 +00:00
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#include "../amdtp-stream.h"
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2017-03-22 12:30:12 +00:00
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ALSA: firewire-motu: add an abstraction layer for three types of protocols
In an aspect of used protocols to communicate, models of MOTU FireWire
units are categorized to three generations.
This commit adds an abstraction layer of the protocols for features
related to packet streaming functionality. This layer includes 5
operations.
When configuring packet streaming functionality with sampling rate and
sampling transmission frequency, .get_clock_rate and .set_clock_rate are
called with proper arguments. MOTU FireWire series supports up to 192.0kHz.
When checking current source of sampling clock (not clock for packetization
layer), .get_clock_source is used. Enumeration is added to represent the
sources supported by this series. This operation can be used to expose
available sampling rate to user space applications when the unit is
configured to use any input signal as source of clock instead of crystal
clock.
In the protocols, the path between packet processing layer and digital
signal processing layer can be controlled. This looks a functionality to
'mute' the unit. For this feature, .switch_fetching_mode is added. This
can be used to suppress noises every time packet streaming starts/stops.
In a point of the size of data blocks at a certain sampling transmission
frequency, the most units accept several modes. This is due to usage of
optical interfaces. The size differs depending on which modes are
configured to the interfaces; None, S/PDIF and ADAT. Additionally, format
of packet is different depending on protocols. To cache current size of
data blocks and its format, .cache_packet_formats is added. This is used
by PCM functionality, packet streaming functionality and data block
processing layer.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-22 12:30:14 +00:00
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struct snd_motu_packet_format {
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unsigned char pcm_byte_offset;
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unsigned char msg_chunks;
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unsigned char fixed_part_pcm_chunks[3];
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unsigned char differed_part_pcm_chunks[3];
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};
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2017-03-22 12:30:11 +00:00
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struct snd_motu {
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struct snd_card *card;
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struct fw_unit *unit;
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struct mutex mutex;
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2017-03-22 12:30:12 +00:00
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bool registered;
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struct delayed_work dwork;
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2017-03-22 12:30:13 +00:00
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/* Model dependent information. */
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const struct snd_motu_spec *spec;
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ALSA: firewire-motu: add an abstraction layer for three types of protocols
In an aspect of used protocols to communicate, models of MOTU FireWire
units are categorized to three generations.
This commit adds an abstraction layer of the protocols for features
related to packet streaming functionality. This layer includes 5
operations.
When configuring packet streaming functionality with sampling rate and
sampling transmission frequency, .get_clock_rate and .set_clock_rate are
called with proper arguments. MOTU FireWire series supports up to 192.0kHz.
When checking current source of sampling clock (not clock for packetization
layer), .get_clock_source is used. Enumeration is added to represent the
sources supported by this series. This operation can be used to expose
available sampling rate to user space applications when the unit is
configured to use any input signal as source of clock instead of crystal
clock.
In the protocols, the path between packet processing layer and digital
signal processing layer can be controlled. This looks a functionality to
'mute' the unit. For this feature, .switch_fetching_mode is added. This
can be used to suppress noises every time packet streaming starts/stops.
In a point of the size of data blocks at a certain sampling transmission
frequency, the most units accept several modes. This is due to usage of
optical interfaces. The size differs depending on which modes are
configured to the interfaces; None, S/PDIF and ADAT. Additionally, format
of packet is different depending on protocols. To cache current size of
data blocks and its format, .cache_packet_formats is added. This is used
by PCM functionality, packet streaming functionality and data block
processing layer.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-22 12:30:14 +00:00
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/* For packet streaming */
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struct snd_motu_packet_format tx_packet_formats;
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struct snd_motu_packet_format rx_packet_formats;
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ALSA: firewire-motu: add MOTU specific protocol layer
MOTU FireWire series uses blocking transmission for AMDTP packet streaming.
They transmit/receive 8,000 packets per second, to handle the same number
of data blocks as current sampling transmission frequency. Thus,
IEC 61883-1/6 packet streaming engine of ALSA firewire stack is available
for them.
However, the sequence of packet and data blocks includes some quirks.
Below sample is a sequence of CIP headers of packets received by 828mk2,
at 44.1kHz of sampling transmission frequency.
quads CIP1 CIP2
488 0x020F04E8 0x8222FFFF
8 0x020F04F8 0x8222FFFF
488 0x020F0400 0x8222FFFF
488 0x020F0408 0x8222FFFF
8 0x020F04E8 0x8222FFFF
488 0x020F04F0 0x8222FFFF
488 0x020F04F8 0x8222FFFF
The SID (source node ID), DBS (data block size), SPH (source packet header),
FMT (format ID), FDF (format dependent field) and SYT (time stamp) fields
are in IEC 61883-1. Especially, FMT is 0x02, FDF is 0x22 and SYT is 0xffff
to define MOTU specific protocol. In an aspect of dbc field, the value
represents accumulated number of data blocks included the packet. This
is against IEC 61883-1, because according to the specification this value
should be the number of data blocks already transferred.
In ALSA IEC 61883-1/6 engine, this quirk is already supported by
CIP_DBC_IS_END_EVENT flag, because Echo Audio Fireworks has.
Each data block includes SPH as its first quadlet field, to represent its
presentation time stamp. Actual value of SPH is compliant to IEC 61883-1;
lower 25 bits of 32 bits width consists of 13 bits cycle count and 12 bits
cycle offset.
The rest of each data block consists of 24 bit chunks. All of PCM samples,
MIDI messages, status and control messages are transferred by the chunks.
This is similar to '24-bit * 4 Audio Pack' in IEC 61883-6. The position of
each kind of data depends on generations of each model. The number of
whole chunks in a data block is a multiple of 4, to consists of
quadlet-aligned packets.
This commit adds data block processing layer specific for the MOTU
protocol. The remarkable point is the way to generate SPH header. Time
stamps for each data blocks are generated by below calculation:
* Using pre-computed table for the number of ticks per event
* 44,1kHz: (557 + 123/441)
* 48.0kHz: (512 + 0/441)
* 88.2kHz: (278 + 282/441)
* 96.0kHz: (256 + 0/441)
* 176.4kHz: (139 + 141/441)
* 192.0kHz: (128 + 0/441)
* Accumulate the ticks and set the value to SPH for every events.
* This way makes sense only for blocking transmission because this mode
transfers fixed number or none of events.
This calculation assumes that each data block has a PCM frame which is
sampled according to event timing clock. Current packet streaming layer
has the same assumption.
Although this sequence works fine for MOTU FireWire series at sampling
transmission frequency based on 48.0kHz, it is not enough at the frequency
based on 44.1kHz. The units generate choppy noise every few seconds.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-22 12:30:18 +00:00
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struct amdtp_stream tx_stream;
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struct amdtp_stream rx_stream;
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2017-03-22 12:30:13 +00:00
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};
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enum snd_motu_spec_flags {
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SND_MOTU_SPEC_SUPPORT_CLOCK_X2 = 0x0001,
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SND_MOTU_SPEC_SUPPORT_CLOCK_X4 = 0x0002,
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SND_MOTU_SPEC_TX_MICINST_CHUNK = 0x0004,
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SND_MOTU_SPEC_TX_RETURN_CHUNK = 0x0008,
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SND_MOTU_SPEC_TX_REVERB_CHUNK = 0x0010,
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SND_MOTU_SPEC_TX_AESEBU_CHUNK = 0x0020,
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SND_MOTU_SPEC_HAS_OPT_IFACE_A = 0x0040,
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SND_MOTU_SPEC_HAS_OPT_IFACE_B = 0x0080,
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SND_MOTU_SPEC_HAS_MIDI = 0x0100,
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};
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ALSA: firewire-motu: add an abstraction layer for three types of protocols
In an aspect of used protocols to communicate, models of MOTU FireWire
units are categorized to three generations.
This commit adds an abstraction layer of the protocols for features
related to packet streaming functionality. This layer includes 5
operations.
When configuring packet streaming functionality with sampling rate and
sampling transmission frequency, .get_clock_rate and .set_clock_rate are
called with proper arguments. MOTU FireWire series supports up to 192.0kHz.
When checking current source of sampling clock (not clock for packetization
layer), .get_clock_source is used. Enumeration is added to represent the
sources supported by this series. This operation can be used to expose
available sampling rate to user space applications when the unit is
configured to use any input signal as source of clock instead of crystal
clock.
In the protocols, the path between packet processing layer and digital
signal processing layer can be controlled. This looks a functionality to
'mute' the unit. For this feature, .switch_fetching_mode is added. This
can be used to suppress noises every time packet streaming starts/stops.
In a point of the size of data blocks at a certain sampling transmission
frequency, the most units accept several modes. This is due to usage of
optical interfaces. The size differs depending on which modes are
configured to the interfaces; None, S/PDIF and ADAT. Additionally, format
of packet is different depending on protocols. To cache current size of
data blocks and its format, .cache_packet_formats is added. This is used
by PCM functionality, packet streaming functionality and data block
processing layer.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-22 12:30:14 +00:00
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#define SND_MOTU_CLOCK_RATE_COUNT 6
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extern const unsigned int snd_motu_clock_rates[SND_MOTU_CLOCK_RATE_COUNT];
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enum snd_motu_clock_source {
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SND_MOTU_CLOCK_SOURCE_INTERNAL,
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SND_MOTU_CLOCK_SOURCE_ADAT_ON_DSUB,
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SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT,
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SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT_A,
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SND_MOTU_CLOCK_SOURCE_ADAT_ON_OPT_B,
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SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT,
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SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT_A,
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SND_MOTU_CLOCK_SOURCE_SPDIF_ON_OPT_B,
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SND_MOTU_CLOCK_SOURCE_SPDIF_ON_COAX,
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SND_MOTU_CLOCK_SOURCE_AESEBU_ON_XLR,
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SND_MOTU_CLOCK_SOURCE_WORD_ON_BNC,
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SND_MOTU_CLOCK_SOURCE_UNKNOWN,
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};
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struct snd_motu_protocol {
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int (*get_clock_rate)(struct snd_motu *motu, unsigned int *rate);
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int (*set_clock_rate)(struct snd_motu *motu, unsigned int rate);
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int (*get_clock_source)(struct snd_motu *motu,
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enum snd_motu_clock_source *source);
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int (*switch_fetching_mode)(struct snd_motu *motu, bool enable);
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int (*cache_packet_formats)(struct snd_motu *motu);
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};
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2017-03-22 12:30:13 +00:00
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struct snd_motu_spec {
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const char *const name;
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enum snd_motu_spec_flags flags;
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unsigned char analog_in_ports;
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unsigned char analog_out_ports;
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ALSA: firewire-motu: add an abstraction layer for three types of protocols
In an aspect of used protocols to communicate, models of MOTU FireWire
units are categorized to three generations.
This commit adds an abstraction layer of the protocols for features
related to packet streaming functionality. This layer includes 5
operations.
When configuring packet streaming functionality with sampling rate and
sampling transmission frequency, .get_clock_rate and .set_clock_rate are
called with proper arguments. MOTU FireWire series supports up to 192.0kHz.
When checking current source of sampling clock (not clock for packetization
layer), .get_clock_source is used. Enumeration is added to represent the
sources supported by this series. This operation can be used to expose
available sampling rate to user space applications when the unit is
configured to use any input signal as source of clock instead of crystal
clock.
In the protocols, the path between packet processing layer and digital
signal processing layer can be controlled. This looks a functionality to
'mute' the unit. For this feature, .switch_fetching_mode is added. This
can be used to suppress noises every time packet streaming starts/stops.
In a point of the size of data blocks at a certain sampling transmission
frequency, the most units accept several modes. This is due to usage of
optical interfaces. The size differs depending on which modes are
configured to the interfaces; None, S/PDIF and ADAT. Additionally, format
of packet is different depending on protocols. To cache current size of
data blocks and its format, .cache_packet_formats is added. This is used
by PCM functionality, packet streaming functionality and data block
processing layer.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-22 12:30:14 +00:00
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const struct snd_motu_protocol *const protocol;
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2017-03-22 12:30:11 +00:00
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};
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ALSA: firewire-motu: add MOTU specific protocol layer
MOTU FireWire series uses blocking transmission for AMDTP packet streaming.
They transmit/receive 8,000 packets per second, to handle the same number
of data blocks as current sampling transmission frequency. Thus,
IEC 61883-1/6 packet streaming engine of ALSA firewire stack is available
for them.
However, the sequence of packet and data blocks includes some quirks.
Below sample is a sequence of CIP headers of packets received by 828mk2,
at 44.1kHz of sampling transmission frequency.
quads CIP1 CIP2
488 0x020F04E8 0x8222FFFF
8 0x020F04F8 0x8222FFFF
488 0x020F0400 0x8222FFFF
488 0x020F0408 0x8222FFFF
8 0x020F04E8 0x8222FFFF
488 0x020F04F0 0x8222FFFF
488 0x020F04F8 0x8222FFFF
The SID (source node ID), DBS (data block size), SPH (source packet header),
FMT (format ID), FDF (format dependent field) and SYT (time stamp) fields
are in IEC 61883-1. Especially, FMT is 0x02, FDF is 0x22 and SYT is 0xffff
to define MOTU specific protocol. In an aspect of dbc field, the value
represents accumulated number of data blocks included the packet. This
is against IEC 61883-1, because according to the specification this value
should be the number of data blocks already transferred.
In ALSA IEC 61883-1/6 engine, this quirk is already supported by
CIP_DBC_IS_END_EVENT flag, because Echo Audio Fireworks has.
Each data block includes SPH as its first quadlet field, to represent its
presentation time stamp. Actual value of SPH is compliant to IEC 61883-1;
lower 25 bits of 32 bits width consists of 13 bits cycle count and 12 bits
cycle offset.
The rest of each data block consists of 24 bit chunks. All of PCM samples,
MIDI messages, status and control messages are transferred by the chunks.
This is similar to '24-bit * 4 Audio Pack' in IEC 61883-6. The position of
each kind of data depends on generations of each model. The number of
whole chunks in a data block is a multiple of 4, to consists of
quadlet-aligned packets.
This commit adds data block processing layer specific for the MOTU
protocol. The remarkable point is the way to generate SPH header. Time
stamps for each data blocks are generated by below calculation:
* Using pre-computed table for the number of ticks per event
* 44,1kHz: (557 + 123/441)
* 48.0kHz: (512 + 0/441)
* 88.2kHz: (278 + 282/441)
* 96.0kHz: (256 + 0/441)
* 176.4kHz: (139 + 141/441)
* 192.0kHz: (128 + 0/441)
* Accumulate the ticks and set the value to SPH for every events.
* This way makes sense only for blocking transmission because this mode
transfers fixed number or none of events.
This calculation assumes that each data block has a PCM frame which is
sampled according to event timing clock. Current packet streaming layer
has the same assumption.
Although this sequence works fine for MOTU FireWire series at sampling
transmission frequency based on 48.0kHz, it is not enough at the frequency
based on 44.1kHz. The units generate choppy noise every few seconds.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-22 12:30:18 +00:00
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int amdtp_motu_init(struct amdtp_stream *s, struct fw_unit *unit,
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enum amdtp_stream_direction dir,
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const struct snd_motu_protocol *const protocol);
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int amdtp_motu_set_parameters(struct amdtp_stream *s, unsigned int rate,
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struct snd_motu_packet_format *formats);
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int amdtp_motu_add_pcm_hw_constraints(struct amdtp_stream *s,
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struct snd_pcm_runtime *runtime);
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2017-03-22 12:30:11 +00:00
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#endif
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