[PATCH 00/11] ALSA: firewire-motu: add ioctl commands to retrieve information in messages delivered by isoc packet

[PATCH 00/11] ALSA: firewire-motu: add ioctl commands to retrieve information in messages delivered by isoc packet

[Takashi Sakamoto]

Hi,

The purpose of this patchset is to add message parser to ALSA
firewire-motu driver so that userspace applications can read information
in message delivered by isochronous packet as well as PCM frames.
The message includes information about hardware meter and user action
over hardware component such as knob, and MIDI message bytes.

Models in MOTU FireWire series can be categorized to 4 groups in regard
of message mechanism:

Group 1. 828 and 896
 * quadlet message to registered destination address
Group 2. 828mk2, 896hd, Traveler, 8 pre, Ultralite, 4 pre, and Audio Express
 * quadlet message to registered destination address
 * message delivered by isochronous packet
Group 3. 828mk3, 896mk3, Ultralite mk3, Traveler mk3, and Track 16
 * quadlet message to registered destination address
 * message delivered by isochronous packet
 * block message to registered destination address, including command
Group 4. V3HD/V4HD
 * quadlet message to registered destination address
 * block message to registered destination address

The patchset is for message delivered by isochronous packet in group 2
and 3. In Group 2, the message includes information of hardware meter,
information of user action over hardware component. The model in Group
2 is called as 'register DSP' in the patchset since parameters of DSP
can be configured by asynchronous transaction for register access. In
Group 3, the message includes information of hardware meter only. The
model in Group 3 is called as 'command DSP' since software and device
communicate with commands transferred by asynchronous transaction in
regard of DSP parameters. Two types of message parser is going to be
added so that the driver caches images for the information. The cache
is available for userspace application by ioctl commands newly introduced.

I note that no control element is added for the hardware meters and user
actions. It's expected for userspace application to retrieve and parse the
information of image then operate for user-defined control element set.

Takashi Sakamoto (11):
  ALSA: firewire-motu: add message parser to gather meter information in
    register DSP model
  ALSA: firewire-motu: add message parser for meter information in
    command DSP model
  ALSA: firewire-motu: add ioctl command to read cached hardware meter
  ALSA: firewire-motu: parse messages for mixer source parameters in
    register-DSP model
  ALSA: firewire-motu: parse messages for mixer output parameters in
    register DSP model
  ALSA: firewire-motu: parse messages for output parameters in register
    DSP model
  ALSA: firewire-motu: parse messages for line input parameters in
    register DSP model
  ALSA: firewire-motu: parse messages for input parameters in register
    DSP model
  ALSA: firewire-motu: add ioctl command to read cached DSP parameters
  ALSA: firewire-motu: queue event for parameter change in register DSP
    model
  ALSA: firewire-motu: notify event for parameter change in register DSP
    model

 include/uapi/sound/firewire.h                 | 141 ++++++
 sound/firewire/motu/Makefile                  |   3 +-
 sound/firewire/motu/amdtp-motu.c              |   9 +
 .../motu/motu-command-dsp-message-parser.c    | 178 ++++++++
 sound/firewire/motu/motu-hwdep.c              | 113 ++++-
 sound/firewire/motu/motu-protocol-v2.c        |  14 +-
 sound/firewire/motu/motu-protocol-v3.c        |  14 +-
 .../motu/motu-register-dsp-message-parser.c   | 416 ++++++++++++++++++
 sound/firewire/motu/motu-stream.c             |  10 +
 sound/firewire/motu/motu.c                    |  10 +
 sound/firewire/motu/motu.h                    |  23 +
 11 files changed, 911 insertions(+), 20 deletions(-)
 create mode 100644 sound/firewire/motu/motu-command-dsp-message-parser.c
 create mode 100644 sound/firewire/motu/motu-register-dsp-message-parser.c

-- 
2.30.2

[PATCH 01/11] ALSA: firewire-motu: add message parser to gather meter information in register DSP model

[Takashi Sakamoto]

Some of MOTU models allows software to configure their DSP parameters by
accessing to their registers. The models multiplex messages for status of
DSP into isochronous packet as well as PCM frames. The message includes
information of hardware metering, MIDI message, current parameters of DSP.
For my convenience, I call them as 'register DSP' model.

This patch adds message parser for them to gather hardware meter
information.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 include/uapi/sound/firewire.h                 |  35 +++++
 sound/firewire/motu/Makefile                  |   2 +-
 sound/firewire/motu/amdtp-motu.c              |   6 +
 sound/firewire/motu/motu-protocol-v2.c        |  14 +-
 sound/firewire/motu/motu-protocol-v3.c        |   4 +-
 .../motu/motu-register-dsp-message-parser.c   | 145 ++++++++++++++++++
 sound/firewire/motu/motu-stream.c             |   6 +
 sound/firewire/motu/motu.c                    |   6 +
 sound/firewire/motu/motu.h                    |   8 +
 9 files changed, 219 insertions(+), 7 deletions(-)
 create mode 100644 sound/firewire/motu/motu-register-dsp-message-parser.c

diff --git a/include/uapi/sound/firewire.h b/include/uapi/sound/firewire.h
index ae12826ed641..347fd7a05596 100644
--- a/include/uapi/sound/firewire.h
+++ b/include/uapi/sound/firewire.h
@@ -108,4 +108,39 @@ struct snd_firewire_tascam_state {
 	__be32 data[SNDRV_FIREWIRE_TASCAM_STATE_COUNT];
 };
 
+// In below MOTU models, software is allowed to control their DSP by accessing to registers.
+//  - 828mk2
+//  - 896hd
+//  - Traveler
+//  - 8 pre
+//  - Ultralite
+//  - 4 pre
+//  - Audio Express
+//
+// On the other hand, the status of DSP is split into specific messages included in the sequence of
+// isochronous packet. ALSA firewire-motu driver gathers the messages and allow userspace applications
+// to read it via ioctl. In 828mk2, 896hd, and Traveler, hardware meter for all of physical inputs
+// are put into the message, while one pair of physical outputs is selected. The selection is done by
+// LSB one byte in asynchronous write quadlet transaction to 0x'ffff'f000'0b2c.
+//
+// I note that V3HD/V4HD uses asynchronous transaction for the purpose. The destination address is
+// registered to 0x'ffff'f000'0b38 and '0b3c by asynchronous write quadlet request. The size of
+// message differs between 23 and 51 quadlets. For the case, the number of mixer bus can be extended
+// up to 12.
+
+#define SNDRV_FIREWIRE_MOTU_REGISTER_DSP_METER_COUNT	40
+
+/**
+ * struct snd_firewire_motu_register_dsp_meter - the container for meter information in DSP
+ *						 controlled by register access
+ * @data: Signal level meters. The mapping between position and input/output channel is
+ *	  model-dependent.
+ *
+ * The structure expresses the part of DSP status for hardware meter. The u8 storage includes linear
+ * value for audio signal level between 0x00 and 0x7f.
+ */
+struct snd_firewire_motu_register_dsp_meter {
+	__u8 data[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_METER_COUNT];
+};
+
 #endif /* _UAPI_SOUND_FIREWIRE_H_INCLUDED */
diff --git a/sound/firewire/motu/Makefile b/sound/firewire/motu/Makefile
index acdf66564fb0..edbdf40c7162 100644
--- a/sound/firewire/motu/Makefile
+++ b/sound/firewire/motu/Makefile
@@ -4,5 +4,5 @@ CFLAGS_amdtp-motu.o	:= -I$(src)
 snd-firewire-motu-objs := motu.o amdtp-motu.o motu-transaction.o motu-stream.o \
 			  motu-proc.o motu-pcm.o motu-midi.o motu-hwdep.o \
 			  motu-protocol-v2.o motu-protocol-v3.o \
-			  motu-protocol-v1.o
+			  motu-protocol-v1.o motu-register-dsp-message-parser.o
 obj-$(CONFIG_SND_FIREWIRE_MOTU) += snd-firewire-motu.o
diff --git a/sound/firewire/motu/amdtp-motu.c b/sound/firewire/motu/amdtp-motu.c
index a18c2c033e83..605b831492ac 100644
--- a/sound/firewire/motu/amdtp-motu.c
+++ b/sound/firewire/motu/amdtp-motu.c
@@ -333,6 +333,7 @@ static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
 					    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;
@@ -357,6 +358,11 @@ static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
 			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);
+	}
+
 	// For tracepoints.
 	if (trace_data_block_sph_enabled() ||
 	    trace_data_block_message_enabled())
diff --git a/sound/firewire/motu/motu-protocol-v2.c b/sound/firewire/motu/motu-protocol-v2.c
index 2bd4485e4bc7..a5f70efa2e88 100644
--- a/sound/firewire/motu/motu-protocol-v2.c
+++ b/sound/firewire/motu/motu-protocol-v2.c
@@ -275,7 +275,8 @@ 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_TX_MIDI_2ND_Q |
+		 SND_MOTU_SPEC_REGISTER_DSP,
 	.tx_fixed_pcm_chunks = {14, 14, 0},
 	.rx_fixed_pcm_chunks = {14, 14, 0},
 };
@@ -283,7 +284,7 @@ const struct snd_motu_spec snd_motu_spec_828mk2 = {
 const struct snd_motu_spec snd_motu_spec_896hd = {
 	.name = "896HD",
 	.protocol_version = SND_MOTU_PROTOCOL_V2,
-	// No support for MIDI.
+	.flags = SND_MOTU_SPEC_REGISTER_DSP,
 	.tx_fixed_pcm_chunks = {14, 14, 8},
 	.rx_fixed_pcm_chunks = {14, 14, 8},
 };
@@ -292,7 +293,8 @@ 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_TX_MIDI_2ND_Q |
+		 SND_MOTU_SPEC_REGISTER_DSP,
 	.tx_fixed_pcm_chunks = {14, 14, 8},
 	.rx_fixed_pcm_chunks = {14, 14, 8},
 };
@@ -301,7 +303,8 @@ 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_TX_MIDI_2ND_Q |
+		 SND_MOTU_SPEC_REGISTER_DSP,
 	.tx_fixed_pcm_chunks = {14, 14, 0},
 	.rx_fixed_pcm_chunks = {14, 14, 0},
 };
@@ -310,7 +313,8 @@ 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_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
index 56e4504e7ec9..d0dd587460de 100644
--- a/sound/firewire/motu/motu-protocol-v3.c
+++ b/sound/firewire/motu/motu-protocol-v3.c
@@ -293,7 +293,8 @@ 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_TX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_REGISTER_DSP,
 	.tx_fixed_pcm_chunks = {10, 10, 0},
 	.rx_fixed_pcm_chunks = {10, 10, 0},
 };
@@ -301,6 +302,7 @@ const struct snd_motu_spec snd_motu_spec_audio_express = {
 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 000000000000..efb9708b5b5f
--- /dev/null
+++ b/sound/firewire/motu/motu-register-dsp-message-parser.c
@@ -0,0 +1,145 @@
+// 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_ASSIGN = 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,
+};
+
+struct msg_parser {
+	struct snd_firewire_motu_register_dsp_meter meter;
+	bool meter_pos_quirk;
+};
+
+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;
+	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)
+{
+	return 0;
+}
+
+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;
+	int i;
+
+	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 METER:
+			{
+				u8 pos;
+
+				if (!meter_pos_quirk)
+					pos = b[MSG_METER_IDX_POS];
+				else
+					pos = b[MSG_METER_IDX_POS_4PRE_AE];
+
+				if (pos < 0x80)
+					pos &= 0x1f;
+				else
+					pos = (pos & 0x1f) + 20;
+				parser->meter.data[pos] = val;
+				break;
+			}
+			default:
+				break;
+			}
+		}
+	}
+}
diff --git a/sound/firewire/motu/motu-stream.c b/sound/firewire/motu/motu-stream.c
index 9e6ca39ebd7f..654b313ba98d 100644
--- a/sound/firewire/motu/motu-stream.c
+++ b/sound/firewire/motu/motu-stream.c
@@ -255,6 +255,12 @@ int snd_motu_stream_start_duplex(struct snd_motu *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;
+		}
+
 		err = begin_session(motu);
 		if (err < 0) {
 			dev_err(&motu->unit->device,
diff --git a/sound/firewire/motu/motu.c b/sound/firewire/motu/motu.c
index f65426238d4c..0edf8f594a55 100644
--- a/sound/firewire/motu/motu.c
+++ b/sound/firewire/motu/motu.c
@@ -112,6 +112,12 @@ static int motu_probe(struct fw_unit *unit, const struct ieee1394_device_id *ent
 	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;
+	}
+
 	err = snd_card_register(card);
 	if (err < 0)
 		goto error;
diff --git a/sound/firewire/motu/motu.h b/sound/firewire/motu/motu.h
index f1a830b358d4..8d6850bb925e 100644
--- a/sound/firewire/motu/motu.h
+++ b/sound/firewire/motu/motu.h
@@ -78,6 +78,8 @@ struct snd_motu {
 	struct amdtp_domain domain;
 
 	struct amdtp_motu_cache cache;
+
+	void *message_parser;
 };
 
 enum snd_motu_spec_flags {
@@ -85,6 +87,7 @@ enum snd_motu_spec_flags {
 	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,
 };
 
 #define SND_MOTU_CLOCK_RATE_COUNT	6
@@ -270,4 +273,9 @@ static inline int snd_motu_protocol_cache_packet_formats(struct snd_motu *motu)
 		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);
+
 #endif
-- 
2.30.2

[PATCH 02/11] ALSA: firewire-motu: add message parser for meter information in command DSP model

[Takashi Sakamoto]

Some of MOTU models allows software to configure their DSP parameters by
command included in asynchronous transaction. The models multiplex messages
for hardware meters into isochronous packet as well as PCM frames. For
convenience, I call them as 'command DSP' model.

This patch adds message parser for them to gather hardware meter
information.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 include/uapi/sound/firewire.h                 |  30 ++++
 sound/firewire/motu/Makefile                  |   3 +-
 sound/firewire/motu/amdtp-motu.c              |   3 +
 .../motu/motu-command-dsp-message-parser.c    | 160 ++++++++++++++++++
 sound/firewire/motu/motu-protocol-v3.c        |  10 +-
 sound/firewire/motu/motu-stream.c             |   4 +
 sound/firewire/motu/motu.c                    |   4 +
 sound/firewire/motu/motu.h                    |   7 +
 8 files changed, 216 insertions(+), 5 deletions(-)
 create mode 100644 sound/firewire/motu/motu-command-dsp-message-parser.c

diff --git a/include/uapi/sound/firewire.h b/include/uapi/sound/firewire.h
index 347fd7a05596..82d4765fbeee 100644
--- a/include/uapi/sound/firewire.h
+++ b/include/uapi/sound/firewire.h
@@ -143,4 +143,34 @@ struct snd_firewire_motu_register_dsp_meter {
 	__u8 data[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_METER_COUNT];
 };
 
+// In below MOTU models, software is allowed to control their DSP by command in frame of
+// asynchronous transaction to 0x'ffff'0001'0000:
+//
+//  - 828 mk3 (FireWire only and Hybrid)
+//  - 896 mk3 (FireWire only and Hybrid)
+//  - Ultralite mk3 (FireWire only and Hybrid)
+//  - Traveler mk3
+//  - Track 16
+//
+// On the other hand, the states of hardware meter is split into specific messages included in the
+// sequence of isochronous packet. ALSA firewire-motu driver gathers the message and allow userspace
+// application to read it via ioctl.
+
+#define SNDRV_FIREWIRE_MOTU_COMMAND_DSP_METER_COUNT	400
+
+/**
+ * struct snd_firewire_motu_command_dsp_meter - the container for meter information in DSP
+ *						controlled by command
+ * @data: Signal level meters. The mapping between position and signal channel is model-dependent.
+ *
+ * The structure expresses the part of DSP status for hardware meter. The 32 bit storage is
+ * estimated to include IEEE 764 32 bit single precision floating point (binary32) value. It is
+ * expected to be linear value (not logarithm) for audio signal level between 0.0 and +1.0. However,
+ * the last two quadlets (data[398] and data[399]) are filled with 0xffffffff since they are the
+ * marker of one period.
+ */
+struct snd_firewire_motu_command_dsp_meter {
+	__u32 data[SNDRV_FIREWIRE_MOTU_COMMAND_DSP_METER_COUNT];
+};
+
 #endif /* _UAPI_SOUND_FIREWIRE_H_INCLUDED */
diff --git a/sound/firewire/motu/Makefile b/sound/firewire/motu/Makefile
index edbdf40c7162..3bef2a0b1e2e 100644
--- a/sound/firewire/motu/Makefile
+++ b/sound/firewire/motu/Makefile
@@ -4,5 +4,6 @@ CFLAGS_amdtp-motu.o	:= -I$(src)
 snd-firewire-motu-objs := motu.o amdtp-motu.o motu-transaction.o motu-stream.o \
 			  motu-proc.o motu-pcm.o motu-midi.o motu-hwdep.o \
 			  motu-protocol-v2.o motu-protocol-v3.o \
-			  motu-protocol-v1.o motu-register-dsp-message-parser.o
+			  motu-protocol-v1.o motu-register-dsp-message-parser.o \
+			  motu-command-dsp-message-parser.o
 obj-$(CONFIG_SND_FIREWIRE_MOTU) += snd-firewire-motu.o
diff --git a/sound/firewire/motu/amdtp-motu.c b/sound/firewire/motu/amdtp-motu.c
index 605b831492ac..3ea91e281147 100644
--- a/sound/firewire/motu/amdtp-motu.c
+++ b/sound/firewire/motu/amdtp-motu.c
@@ -361,6 +361,9 @@ static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
 	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.
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 000000000000..6716074f8bc1
--- /dev/null
+++ b/sound/firewire/motu/motu-command-dsp-message-parser.c
@@ -0,0 +1,160 @@
+// 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 {
+	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;
+	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;
+	int i;
+
+	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) {
+						if (parser->value_index <
+						    SNDRV_FIREWIRE_MOTU_COMMAND_DSP_METER_COUNT) {
+							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;
+			}
+			}
+		}
+	}
+}
diff --git a/sound/firewire/motu/motu-protocol-v3.c b/sound/firewire/motu/motu-protocol-v3.c
index d0dd587460de..05608e8ca0bc 100644
--- a/sound/firewire/motu/motu-protocol-v3.c
+++ b/sound/firewire/motu/motu-protocol-v3.c
@@ -261,12 +261,12 @@ int snd_motu_protocol_v3_cache_packet_formats(struct snd_motu *motu)
 		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_TX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_COMMAND_DSP,
 	.tx_fixed_pcm_chunks = {18, 18, 14},
 	.rx_fixed_pcm_chunks = {14, 14, 10},
 };
@@ -275,7 +275,8 @@ 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_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.
 };
@@ -284,7 +285,8 @@ 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_TX_MIDI_3RD_Q |
+		 SND_MOTU_SPEC_COMMAND_DSP,
 	.tx_fixed_pcm_chunks = {18, 14, 10},
 	.rx_fixed_pcm_chunks = {14, 14, 14},
 };
diff --git a/sound/firewire/motu/motu-stream.c b/sound/firewire/motu/motu-stream.c
index 654b313ba98d..64aec9c3eefd 100644
--- a/sound/firewire/motu/motu-stream.c
+++ b/sound/firewire/motu/motu-stream.c
@@ -259,6 +259,10 @@ int snd_motu_stream_start_duplex(struct snd_motu *motu)
 			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);
diff --git a/sound/firewire/motu/motu.c b/sound/firewire/motu/motu.c
index 0edf8f594a55..5fc7ae475537 100644
--- a/sound/firewire/motu/motu.c
+++ b/sound/firewire/motu/motu.c
@@ -116,6 +116,10 @@ static int motu_probe(struct fw_unit *unit, const struct ieee1394_device_id *ent
 		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);
diff --git a/sound/firewire/motu/motu.h b/sound/firewire/motu/motu.h
index 8d6850bb925e..d818ce4901c9 100644
--- a/sound/firewire/motu/motu.h
+++ b/sound/firewire/motu/motu.h
@@ -88,6 +88,7 @@ enum snd_motu_spec_flags {
 	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
@@ -278,4 +279,10 @@ 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);
 
+
+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);
+
 #endif
-- 
2.30.2

[PATCH 03/11] ALSA: firewire-motu: add ioctl command to read cached hardware meter

[Takashi Sakamoto]

This patch adds new ioctl commands for userspace applications to read
cached image about hardware meters in register DSP and command DSP models.

The content of image differs depending on models. Model-specific parser
should be implemented in userspace.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 include/uapi/sound/firewire.h                 |  2 +
 .../motu/motu-command-dsp-message-parser.c    | 18 ++++++++
 sound/firewire/motu/motu-hwdep.c              | 44 +++++++++++++++++++
 .../motu/motu-register-dsp-message-parser.c   | 18 ++++++++
 sound/firewire/motu/motu.h                    |  4 ++
 5 files changed, 86 insertions(+)

diff --git a/include/uapi/sound/firewire.h b/include/uapi/sound/firewire.h
index 82d4765fbeee..a8df8fb03b52 100644
--- a/include/uapi/sound/firewire.h
+++ b/include/uapi/sound/firewire.h
@@ -80,6 +80,8 @@ union snd_firewire_event {
 #define SNDRV_FIREWIRE_IOCTL_LOCK      _IO('H', 0xf9)
 #define SNDRV_FIREWIRE_IOCTL_UNLOCK    _IO('H', 0xfa)
 #define SNDRV_FIREWIRE_IOCTL_TASCAM_STATE _IOR('H', 0xfb, struct snd_firewire_tascam_state)
+#define SNDRV_FIREWIRE_IOCTL_MOTU_REGISTER_DSP_METER	_IOR('H', 0xfc, struct snd_firewire_motu_register_dsp_meter)
+#define SNDRV_FIREWIRE_IOCTL_MOTU_COMMAND_DSP_METER	_IOR('H', 0xfd, struct snd_firewire_motu_command_dsp_meter)
 
 #define SNDRV_FIREWIRE_TYPE_DICE	1
 #define SNDRV_FIREWIRE_TYPE_FIREWORKS	2
diff --git a/sound/firewire/motu/motu-command-dsp-message-parser.c b/sound/firewire/motu/motu-command-dsp-message-parser.c
index 6716074f8bc1..18689fcfb288 100644
--- a/sound/firewire/motu/motu-command-dsp-message-parser.c
+++ b/sound/firewire/motu/motu-command-dsp-message-parser.c
@@ -23,6 +23,7 @@ enum msg_parser_state {
 };
 
 struct msg_parser {
+	spinlock_t lock;
 	enum msg_parser_state state;
 	unsigned int interval;
 	unsigned int message_count;
@@ -39,6 +40,7 @@ int snd_motu_command_dsp_message_parser_new(struct snd_motu *motu)
 	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;
@@ -83,8 +85,11 @@ void snd_motu_command_dsp_message_parser_parse(struct snd_motu *motu, const stru
 {
 	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;
@@ -157,4 +162,17 @@ void snd_motu_command_dsp_message_parser_parse(struct snd_motu *motu, const stru
 			}
 		}
 	}
+
+	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
index b5ced5d27758..7be576fe4516 100644
--- a/sound/firewire/motu/motu-hwdep.c
+++ b/sound/firewire/motu/motu-hwdep.c
@@ -155,6 +155,50 @@ static int hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file,
 		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;
+	}
 	default:
 		return -ENOIOCTLCMD;
 	}
diff --git a/sound/firewire/motu/motu-register-dsp-message-parser.c b/sound/firewire/motu/motu-register-dsp-message-parser.c
index efb9708b5b5f..fe804615294c 100644
--- a/sound/firewire/motu/motu-register-dsp-message-parser.c
+++ b/sound/firewire/motu/motu-register-dsp-message-parser.c
@@ -79,6 +79,7 @@ enum register_dsp_msg_type {
 };
 
 struct msg_parser {
+	spinlock_t lock;
 	struct snd_firewire_motu_register_dsp_meter meter;
 	bool meter_pos_quirk;
 };
@@ -89,6 +90,7 @@ int snd_motu_register_dsp_message_parser_new(struct snd_motu *motu)
 	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;
@@ -105,8 +107,11 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 {
 	struct msg_parser *parser = motu->message_parser;
 	bool meter_pos_quirk = parser->meter_pos_quirk;
+	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;
@@ -142,4 +147,17 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 			}
 		}
 	}
+
+	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);
 }
diff --git a/sound/firewire/motu/motu.h b/sound/firewire/motu/motu.h
index d818ce4901c9..4f70036dea25 100644
--- a/sound/firewire/motu/motu.h
+++ b/sound/firewire/motu/motu.h
@@ -278,11 +278,15 @@ 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);
 
 
 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
-- 
2.30.2

[PATCH 04/11] ALSA: firewire-motu: parse messages for mixer source parameters in register-DSP model

[Takashi Sakamoto]

In register DSP models, current parameters of DSP are always reported by
messages in isochronous packet. When user operates hardware component such
as rotary knob, corresponding message is changed.

This commit parses the message and cache current parameters of mixer
source function, commonly available for all of register DSP models.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 include/uapi/sound/firewire.h                 | 28 ++++++++
 .../motu/motu-register-dsp-message-parser.c   | 64 +++++++++++++++++++
 2 files changed, 92 insertions(+)

diff --git a/include/uapi/sound/firewire.h b/include/uapi/sound/firewire.h
index a8df8fb03b52..bb5ecff73896 100644
--- a/include/uapi/sound/firewire.h
+++ b/include/uapi/sound/firewire.h
@@ -145,6 +145,34 @@ struct snd_firewire_motu_register_dsp_meter {
 	__u8 data[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_METER_COUNT];
 };
 
+#define SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT		4
+#define SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT	20
+
+/**
+ * snd_firewire_motu_register_dsp_parameter - the container for parameters of DSP controlled
+ *					      by register access.
+ * @mixer.source.gain: The gain of source to mixer.
+ * @mixer.source.pan: The L/R balance of source to mixer.
+ * @mixer.source.flag: The flag of source to mixer, including mute, solo.
+ * @mixer.source.paired_balance: The L/R balance of paired source to mixer, only for 4 pre and
+ *				 Audio Express.
+ * @mixer.source.paired_width: The width of paired source to mixer, only for 4 pre and
+ *			       Audio Express.
+ *
+ * The structure expresses the set of parameters for DSP controlled by register access.
+ */
+struct snd_firewire_motu_register_dsp_parameter {
+	struct {
+		struct {
+			__u8 gain[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT];
+			__u8 pan[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT];
+			__u8 flag[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT];
+			__u8 paired_balance[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT];
+			__u8 paired_width[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT];
+		} source[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT];
+	} mixer;
+};
+
 // In below MOTU models, software is allowed to control their DSP by command in frame of
 // asynchronous transaction to 0x'ffff'0001'0000:
 //
diff --git a/sound/firewire/motu/motu-register-dsp-message-parser.c b/sound/firewire/motu/motu-register-dsp-message-parser.c
index fe804615294c..6df40e5ee9db 100644
--- a/sound/firewire/motu/motu-register-dsp-message-parser.c
+++ b/sound/firewire/motu/motu-register-dsp-message-parser.c
@@ -82,6 +82,11 @@ 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;
 };
 
 int snd_motu_register_dsp_message_parser_new(struct snd_motu *motu)
@@ -99,6 +104,12 @@ int snd_motu_register_dsp_message_parser_new(struct snd_motu *motu)
 
 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;
+
 	return 0;
 }
 
@@ -126,6 +137,59 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 			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:
+						param->mixer.source[mixer_ch].gain[mixer_src_ch] = val;
+						break;
+					case MIXER_SRC_PAN:
+						param->mixer.source[mixer_ch].pan[mixer_src_ch] = val;
+						break;
+					case MIXER_SRC_FLAG:
+						param->mixer.source[mixer_ch].flag[mixer_src_ch] = val;
+						break;
+					case MIXER_SRC_PAIRED_BALANCE:
+						param->mixer.source[mixer_ch].paired_balance[mixer_src_ch] = val;
+						break;
+					case MIXER_SRC_PAIRED_WIDTH:
+						param->mixer.source[mixer_ch].paired_width[mixer_src_ch] = val;
+						break;
+					default:
+						break;
+					}
+
+					parser->mixer_src_ch = mixer_src_ch;
+				}
+				break;
+			}
 			case METER:
 			{
 				u8 pos;
-- 
2.30.2

[PATCH 05/11] ALSA: firewire-motu: parse messages for mixer output parameters in register DSP model

[Takashi Sakamoto]

This commit parses message and cache current parameters of mixer output
function, commonly available for all of register DSP model

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 include/uapi/sound/firewire.h                 |  6 ++++++
 .../motu/motu-register-dsp-message-parser.c   | 20 +++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/include/uapi/sound/firewire.h b/include/uapi/sound/firewire.h
index bb5ecff73896..f663a26c5205 100644
--- a/include/uapi/sound/firewire.h
+++ b/include/uapi/sound/firewire.h
@@ -158,6 +158,8 @@ struct snd_firewire_motu_register_dsp_meter {
  *				 Audio Express.
  * @mixer.source.paired_width: The width of paired source to mixer, only for 4 pre and
  *			       Audio Express.
+ * @mixer.output.paired_volume: The volume of paired output from mixer.
+ * @mixer.output.paired_flag: The flag of paired output from mixer.
  *
  * The structure expresses the set of parameters for DSP controlled by register access.
  */
@@ -170,6 +172,10 @@ struct snd_firewire_motu_register_dsp_parameter {
 			__u8 paired_balance[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT];
 			__u8 paired_width[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT];
 		} source[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT];
+		struct {
+			__u8 paired_volume[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT];
+			__u8 paired_flag[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT];
+		} output;
 	} mixer;
 };
 
diff --git a/sound/firewire/motu/motu-register-dsp-message-parser.c b/sound/firewire/motu/motu-register-dsp-message-parser.c
index 6df40e5ee9db..867cb09a3521 100644
--- a/sound/firewire/motu/motu-register-dsp-message-parser.c
+++ b/sound/firewire/motu/motu-register-dsp-message-parser.c
@@ -190,6 +190,26 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 				}
 				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:
+						param->mixer.output.paired_volume[mixer_ch] = val;
+						break;
+					case MIXER_OUTPUT_PAIRED_FLAG:
+						param->mixer.output.paired_flag[mixer_ch] = val;
+						break;
+					default:
+						break;
+					}
+				}
+				break;
+			}
 			case METER:
 			{
 				u8 pos;
-- 
2.30.2

[PATCH 06/11] ALSA: firewire-motu: parse messages for output parameters in register DSP model

[Takashi Sakamoto]

This commit parses message and cache current parameters of output
function, commonly available for all of register DSP model.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 include/uapi/sound/firewire.h                         | 10 ++++++++++
 .../firewire/motu/motu-register-dsp-message-parser.c  | 11 ++++++++++-
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/include/uapi/sound/firewire.h b/include/uapi/sound/firewire.h
index f663a26c5205..16ca7b43568b 100644
--- a/include/uapi/sound/firewire.h
+++ b/include/uapi/sound/firewire.h
@@ -160,6 +160,10 @@ struct snd_firewire_motu_register_dsp_meter {
  *			       Audio Express.
  * @mixer.output.paired_volume: The volume of paired output from mixer.
  * @mixer.output.paired_flag: The flag of paired output from mixer.
+ * @output.main_paired_volume: The volume of paired main output.
+ * @output.hp_paired_volume: The volume of paired hp output.
+ * @output.hp_paired_assignment: The source assigned to paired hp output.
+ * @output.reserved: Padding for 32 bit alignment for future extension.
  *
  * The structure expresses the set of parameters for DSP controlled by register access.
  */
@@ -177,6 +181,12 @@ struct snd_firewire_motu_register_dsp_parameter {
 			__u8 paired_flag[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT];
 		} output;
 	} mixer;
+	struct {
+		__u8 main_paired_volume;
+		__u8 hp_paired_volume;
+		__u8 hp_paired_assignment;
+		__u8 reserved[5];
+	} output;
 };
 
 // In below MOTU models, software is allowed to control their DSP by command in frame of
diff --git a/sound/firewire/motu/motu-register-dsp-message-parser.c b/sound/firewire/motu/motu-register-dsp-message-parser.c
index 867cb09a3521..244f7ada851f 100644
--- a/sound/firewire/motu/motu-register-dsp-message-parser.c
+++ b/sound/firewire/motu/motu-register-dsp-message-parser.c
@@ -54,7 +54,7 @@ enum register_dsp_msg_type {
 	MIXER_OUTPUT_PAIRED_FLAG = 0x06,
 	MAIN_OUTPUT_PAIRED_VOLUME = 0x07,
 	HP_OUTPUT_PAIRED_VOLUME = 0x08,
-	HP_OUTPUT_ASSIGN = 0x09,
+	HP_OUTPUT_PAIRED_ASSIGNMENT = 0x09,
 	// Transferred by all models but the purpose is still unknown.
 	UNKNOWN_0 = 0x0a,
 	// Specific to 828mk2, 896hd, Traveler.
@@ -210,6 +210,15 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 				}
 				break;
 			}
+			case MAIN_OUTPUT_PAIRED_VOLUME:
+				parser->param.output.main_paired_volume = val;
+				break;
+			case HP_OUTPUT_PAIRED_VOLUME:
+				parser->param.output.hp_paired_volume = val;
+				break;
+			case HP_OUTPUT_PAIRED_ASSIGNMENT:
+				parser->param.output.hp_paired_assignment = val;
+				break;
 			case METER:
 			{
 				u8 pos;
-- 
2.30.2

[PATCH 07/11] ALSA: firewire-motu: parse messages for line input parameters in register DSP model

[Takashi Sakamoto]

This commit parses message and cache current parameters of line input
function, available for MOTU 828 mk2 and Traveler.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 include/uapi/sound/firewire.h                          | 9 +++++++++
 sound/firewire/motu/motu-register-dsp-message-parser.c | 6 ++++++
 2 files changed, 15 insertions(+)

diff --git a/include/uapi/sound/firewire.h b/include/uapi/sound/firewire.h
index 16ca7b43568b..049934e2a53c 100644
--- a/include/uapi/sound/firewire.h
+++ b/include/uapi/sound/firewire.h
@@ -164,6 +164,10 @@ struct snd_firewire_motu_register_dsp_meter {
  * @output.hp_paired_volume: The volume of paired hp output.
  * @output.hp_paired_assignment: The source assigned to paired hp output.
  * @output.reserved: Padding for 32 bit alignment for future extension.
+ * @line_input.boost_flag: The flags of boost for line inputs, only for 828mk2 and Traveler.
+ * @line_input.nominal_level_flag: The flags of nominal level for line inputs, only for 828mk2 and
+ *				   Traveler.
+ * @line_input.reserved: Padding for 32 bit alignment for future extension.
  *
  * The structure expresses the set of parameters for DSP controlled by register access.
  */
@@ -187,6 +191,11 @@ struct snd_firewire_motu_register_dsp_parameter {
 		__u8 hp_paired_assignment;
 		__u8 reserved[5];
 	} output;
+	struct {
+		__u8 boost_flag;
+		__u8 nominal_level_flag;
+		__u8 reserved[6];
+	} line_input;
 };
 
 // In below MOTU models, software is allowed to control their DSP by command in frame of
diff --git a/sound/firewire/motu/motu-register-dsp-message-parser.c b/sound/firewire/motu/motu-register-dsp-message-parser.c
index 244f7ada851f..85faf7a4e8a3 100644
--- a/sound/firewire/motu/motu-register-dsp-message-parser.c
+++ b/sound/firewire/motu/motu-register-dsp-message-parser.c
@@ -219,6 +219,12 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 			case HP_OUTPUT_PAIRED_ASSIGNMENT:
 				parser->param.output.hp_paired_assignment = val;
 				break;
+			case LINE_INPUT_BOOST:
+				parser->param.line_input.boost_flag = val;
+				break;
+			case LINE_INPUT_NOMINAL_LEVEL:
+				parser->param.line_input.nominal_level_flag = val;
+				break;
 			case METER:
 			{
 				u8 pos;
-- 
2.30.2

[PATCH 08/11] ALSA: firewire-motu: parse messages for input parameters in register DSP model

[Takashi Sakamoto]

This commit parses message and cache current parameters of input function,
available for MOTU Ultralite, 4 pre, and Audio Express.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 include/uapi/sound/firewire.h                 | 12 ++++++
 .../motu/motu-register-dsp-message-parser.c   | 43 ++++++++++++++++++-
 2 files changed, 53 insertions(+), 2 deletions(-)

diff --git a/include/uapi/sound/firewire.h b/include/uapi/sound/firewire.h
index 049934e2a53c..6366127e923e 100644
--- a/include/uapi/sound/firewire.h
+++ b/include/uapi/sound/firewire.h
@@ -147,6 +147,8 @@ struct snd_firewire_motu_register_dsp_meter {
 
 #define SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT		4
 #define SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_SRC_COUNT	20
+#define SNDRV_FIREWIRE_MOTU_REGISTER_DSP_INPUT_COUNT		10
+#define SNDRV_FIREWIRE_MOTU_REGISTER_DSP_ALIGNED_INPUT_COUNT	(SNDRV_FIREWIRE_MOTU_REGISTER_DSP_INPUT_COUNT + 2)
 
 /**
  * snd_firewire_motu_register_dsp_parameter - the container for parameters of DSP controlled
@@ -168,6 +170,11 @@ struct snd_firewire_motu_register_dsp_meter {
  * @line_input.nominal_level_flag: The flags of nominal level for line inputs, only for 828mk2 and
  *				   Traveler.
  * @line_input.reserved: Padding for 32 bit alignment for future extension.
+ * @input.gain_and_invert: The value including gain and invert for input, only for Ultralite, 4 pre
+ *			   and Audio Express.
+ * @input.flag: The flag of input; e.g. jack detection, phantom power, and pad, only for Ultralite,
+ *		4 pre and Audio express.
+ * @reserved: Padding so that the size of structure is kept to 512 byte, but for future extension.
  *
  * The structure expresses the set of parameters for DSP controlled by register access.
  */
@@ -196,6 +203,11 @@ struct snd_firewire_motu_register_dsp_parameter {
 		__u8 nominal_level_flag;
 		__u8 reserved[6];
 	} line_input;
+	struct {
+		__u8 gain_and_invert[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_ALIGNED_INPUT_COUNT];
+		__u8 flag[SNDRV_FIREWIRE_MOTU_REGISTER_DSP_ALIGNED_INPUT_COUNT];
+	} input;
+	__u8 reserved[64];
 };
 
 // In below MOTU models, software is allowed to control their DSP by command in frame of
diff --git a/sound/firewire/motu/motu-register-dsp-message-parser.c b/sound/firewire/motu/motu-register-dsp-message-parser.c
index 85faf7a4e8a3..d94ca4875714 100644
--- a/sound/firewire/motu/motu-register-dsp-message-parser.c
+++ b/sound/firewire/motu/motu-register-dsp-message-parser.c
@@ -87,6 +87,9 @@ struct msg_parser {
 	u8 prev_mixer_src_type;
 	u8 mixer_ch;
 	u8 mixer_src_ch;
+
+	u8 input_ch;
+	u8 prev_msg_type;
 };
 
 int snd_motu_register_dsp_message_parser_new(struct snd_motu *motu)
@@ -109,6 +112,7 @@ int snd_motu_register_dsp_message_parser_init(struct snd_motu *motu)
 	parser->prev_mixer_src_type = INVALID;
 	parser->mixer_ch = 0xff;
 	parser->mixer_src_ch = 0xff;
+	parser->prev_msg_type = INVALID;
 
 	return 0;
 }
@@ -225,6 +229,35 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 			case LINE_INPUT_NOMINAL_LEVEL:
 				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:
+						param->input.gain_and_invert[input_ch] = val;
+						break;
+					case INPUT_FLAG:
+						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;
@@ -239,11 +272,17 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 				else
 					pos = (pos & 0x1f) + 20;
 				parser->meter.data[pos] = val;
-				break;
+				// The message for meter is interruptible to the series of other
+				// types of messages. Don't cache it.
+				fallthrough;
 			}
+			case INVALID:
 			default:
-				break;
+				// Don't cache it.
+				continue;
 			}
+
+			parser->prev_msg_type = msg_type;
 		}
 	}
 
-- 
2.30.2

[PATCH 09/11] ALSA: firewire-motu: add ioctl command to read cached parameters in register DSP model

[Takashi Sakamoto]

This patch adds new ioctl command for userspace applications to read
cached parameters of register DSP.

The structured data includes model-dependent parameters. Userspace
application should be carefully programmed so that what parameter is
common and specific.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 include/uapi/sound/firewire.h                 |  1 +
 sound/firewire/motu/motu-hwdep.c              | 21 +++++++++++++++++++
 .../motu/motu-register-dsp-message-parser.c   | 11 ++++++++++
 sound/firewire/motu/motu.h                    |  3 ++-
 4 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/include/uapi/sound/firewire.h b/include/uapi/sound/firewire.h
index 6366127e923e..d52691655d79 100644
--- a/include/uapi/sound/firewire.h
+++ b/include/uapi/sound/firewire.h
@@ -82,6 +82,7 @@ union snd_firewire_event {
 #define SNDRV_FIREWIRE_IOCTL_TASCAM_STATE _IOR('H', 0xfb, struct snd_firewire_tascam_state)
 #define SNDRV_FIREWIRE_IOCTL_MOTU_REGISTER_DSP_METER	_IOR('H', 0xfc, struct snd_firewire_motu_register_dsp_meter)
 #define SNDRV_FIREWIRE_IOCTL_MOTU_COMMAND_DSP_METER	_IOR('H', 0xfd, struct snd_firewire_motu_command_dsp_meter)
+#define SNDRV_FIREWIRE_IOCTL_MOTU_REGISTER_DSP_PARAMETER	_IOR('H', 0xfe, struct snd_firewire_motu_register_dsp_parameter)
 
 #define SNDRV_FIREWIRE_TYPE_DICE	1
 #define SNDRV_FIREWIRE_TYPE_FIREWORKS	2
diff --git a/sound/firewire/motu/motu-hwdep.c b/sound/firewire/motu/motu-hwdep.c
index 7be576fe4516..699136b911c7 100644
--- a/sound/firewire/motu/motu-hwdep.c
+++ b/sound/firewire/motu/motu-hwdep.c
@@ -199,6 +199,27 @@ static int hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file,
 
 		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;
 	}
diff --git a/sound/firewire/motu/motu-register-dsp-message-parser.c b/sound/firewire/motu/motu-register-dsp-message-parser.c
index d94ca4875714..ed9fd0cef200 100644
--- a/sound/firewire/motu/motu-register-dsp-message-parser.c
+++ b/sound/firewire/motu/motu-register-dsp-message-parser.c
@@ -299,3 +299,14 @@ void snd_motu_register_dsp_message_parser_copy_meter(struct snd_motu *motu,
 	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);
+}
diff --git a/sound/firewire/motu/motu.h b/sound/firewire/motu/motu.h
index 4f70036dea25..fa0b3ab7b78d 100644
--- a/sound/firewire/motu/motu.h
+++ b/sound/firewire/motu/motu.h
@@ -280,7 +280,8 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 					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);
 
 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);
-- 
2.30.2

[PATCH 10/11] ALSA: firewire-motu: queue event for parameter change in register DSP model

[Takashi Sakamoto]

This commit is a preparation to notify parameter change of register DSP
to userspace application. A simple queue is added to store encoded data
for the change as long as ALSA hwdep character device is opened by
application.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 sound/firewire/motu/motu-hwdep.c              |  2 +
 .../motu/motu-register-dsp-message-parser.c   | 93 ++++++++++++++++---
 sound/firewire/motu/motu.h                    |  1 +
 3 files changed, 82 insertions(+), 14 deletions(-)

diff --git a/sound/firewire/motu/motu-hwdep.c b/sound/firewire/motu/motu-hwdep.c
index 699136b911c7..389e59ff768b 100644
--- a/sound/firewire/motu/motu-hwdep.c
+++ b/sound/firewire/motu/motu-hwdep.c
@@ -258,5 +258,7 @@ int snd_motu_create_hwdep_device(struct snd_motu *motu)
 	hwdep->private_data = motu;
 	hwdep->exclusive = true;
 
+	motu->hwdep = hwdep;
+
 	return 0;
 }
diff --git a/sound/firewire/motu/motu-register-dsp-message-parser.c b/sound/firewire/motu/motu-register-dsp-message-parser.c
index ed9fd0cef200..cda8e6d987cc 100644
--- a/sound/firewire/motu/motu-register-dsp-message-parser.c
+++ b/sound/firewire/motu/motu-register-dsp-message-parser.c
@@ -78,6 +78,8 @@ enum register_dsp_msg_type {
 	METER = 0x1f,
 };
 
+#define EVENT_QUEUE_SIZE	16
+
 struct msg_parser {
 	spinlock_t lock;
 	struct snd_firewire_motu_register_dsp_meter meter;
@@ -90,6 +92,9 @@ struct msg_parser {
 
 	u8 input_ch;
 	u8 prev_msg_type;
+
+	u32 event_queue[EVENT_QUEUE_SIZE];
+	unsigned int push_pos;
 };
 
 int snd_motu_register_dsp_message_parser_new(struct snd_motu *motu)
@@ -117,6 +122,24 @@ int snd_motu_register_dsp_message_parser_init(struct snd_motu *motu)
 	return 0;
 }
 
+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)
 {
@@ -172,19 +195,34 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 
 					switch (msg_type) {
 					case MIXER_SRC_GAIN:
-						param->mixer.source[mixer_ch].gain[mixer_src_ch] = val;
+						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:
-						param->mixer.source[mixer_ch].pan[mixer_src_ch] = val;
+						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:
-						param->mixer.source[mixer_ch].flag[mixer_src_ch] = val;
+						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:
-						param->mixer.source[mixer_ch].paired_balance[mixer_src_ch] = val;
+						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:
-						param->mixer.source[mixer_ch].paired_width[mixer_src_ch] = val;
+						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;
@@ -203,10 +241,16 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 				if (mixer_ch < SNDRV_FIREWIRE_MOTU_REGISTER_DSP_MIXER_COUNT) {
 					switch (msg_type) {
 					case MIXER_OUTPUT_PAIRED_VOLUME:
-						param->mixer.output.paired_volume[mixer_ch] = val;
+						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:
-						param->mixer.output.paired_flag[mixer_ch] = val;
+						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;
@@ -215,19 +259,34 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 				break;
 			}
 			case MAIN_OUTPUT_PAIRED_VOLUME:
-				parser->param.output.main_paired_volume = val;
+				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:
-				parser->param.output.hp_paired_volume = val;
+				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:
-				parser->param.output.hp_paired_assignment = val;
+				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:
-				parser->param.line_input.boost_flag = val;
+				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:
-				parser->param.line_input.nominal_level_flag = val;
+				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:
@@ -243,10 +302,16 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 				if (input_ch < SNDRV_FIREWIRE_MOTU_REGISTER_DSP_INPUT_COUNT) {
 					switch (msg_type) {
 					case INPUT_GAIN_AND_INVERT:
-						param->input.gain_and_invert[input_ch] = val;
+						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:
-						param->input.flag[input_ch] = val;
+						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;
diff --git a/sound/firewire/motu/motu.h b/sound/firewire/motu/motu.h
index fa0b3ab7b78d..9703d3af59ec 100644
--- a/sound/firewire/motu/motu.h
+++ b/sound/firewire/motu/motu.h
@@ -74,6 +74,7 @@ struct snd_motu {
 	int dev_lock_count;
 	bool dev_lock_changed;
 	wait_queue_head_t hwdep_wait;
+	struct snd_hwdep *hwdep;
 
 	struct amdtp_domain domain;
 
-- 
2.30.2

[PATCH 11/11] ALSA: firewire-motu: notify event for parameter change in register DSP model

[Takashi Sakamoto]

This commit copies queued event for change of register DSP into
userspace when application operates ALSA hwdep character device.
The notification occurs only when packet streaming is running.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 include/uapi/sound/firewire.h                 |  8 ++++
 sound/firewire/motu/motu-hwdep.c              | 46 +++++++++++++++----
 .../motu/motu-register-dsp-message-parser.c   | 39 ++++++++++++++++
 sound/firewire/motu/motu.h                    |  2 +
 4 files changed, 86 insertions(+), 9 deletions(-)

diff --git a/include/uapi/sound/firewire.h b/include/uapi/sound/firewire.h
index d52691655d79..76190a0cb069 100644
--- a/include/uapi/sound/firewire.h
+++ b/include/uapi/sound/firewire.h
@@ -13,6 +13,7 @@
 #define SNDRV_FIREWIRE_EVENT_DIGI00X_MESSAGE	0x746e736c
 #define SNDRV_FIREWIRE_EVENT_MOTU_NOTIFICATION	0x64776479
 #define SNDRV_FIREWIRE_EVENT_TASCAM_CONTROL	0x7473636d
+#define SNDRV_FIREWIRE_EVENT_MOTU_REGISTER_DSP_CHANGE	0x4d545244
 
 struct snd_firewire_event_common {
 	unsigned int type; /* SNDRV_FIREWIRE_EVENT_xxx */
@@ -65,6 +66,12 @@ struct snd_firewire_event_tascam_control {
 	struct snd_firewire_tascam_change changes[0];
 };
 
+struct snd_firewire_event_motu_register_dsp_change {
+	unsigned int type;
+	__u32 count;		// The number of changes.
+	__u32 changes[];	// Encoded event for change of register DSP.
+};
+
 union snd_firewire_event {
 	struct snd_firewire_event_common            common;
 	struct snd_firewire_event_lock_status       lock_status;
@@ -73,6 +80,7 @@ union snd_firewire_event {
 	struct snd_firewire_event_digi00x_message   digi00x_message;
 	struct snd_firewire_event_tascam_control    tascam_control;
 	struct snd_firewire_event_motu_notification motu_notification;
+	struct snd_firewire_event_motu_register_dsp_change motu_register_dsp_change;
 };
 
 
diff --git a/sound/firewire/motu/motu-hwdep.c b/sound/firewire/motu/motu-hwdep.c
index 389e59ff768b..9c2e457ce692 100644
--- a/sound/firewire/motu/motu-hwdep.c
+++ b/sound/firewire/motu/motu-hwdep.c
@@ -25,7 +25,8 @@ static long hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count,
 
 	spin_lock_irq(&motu->lock);
 
-	while (!motu->dev_lock_changed && motu->msg == 0) {
+	while (!motu->dev_lock_changed && motu->msg == 0 &&
+			snd_motu_register_dsp_message_parser_count_event(motu) == 0) {
 		prepare_to_wait(&motu->hwdep_wait, &wait, TASK_INTERRUPTIBLE);
 		spin_unlock_irq(&motu->lock);
 		schedule();
@@ -40,20 +41,46 @@ static long hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count,
 		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.lock_status));
-	} else {
+		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.motu_notification));
-	}
+		count = min_t(long, count, sizeof(event));
+		if (copy_to_user(buf, &event, count))
+			return -EFAULT;
+	} else if (snd_motu_register_dsp_message_parser_count_event(motu) > 0) {
+		size_t consumed = 0;
+		u32 __user *ptr;
+		u32 ev;
 
-	spin_unlock_irq(&motu->lock);
+		spin_unlock_irq(&motu->lock);
 
-	if (copy_to_user(buf, &event, count))
-		return -EFAULT;
+		// 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;
+	}
 
 	return count;
 }
@@ -67,7 +94,8 @@ static __poll_t hwdep_poll(struct snd_hwdep *hwdep, struct file *file,
 	poll_wait(file, &motu->hwdep_wait, wait);
 
 	spin_lock_irq(&motu->lock);
-	if (motu->dev_lock_changed || motu->msg)
+	if (motu->dev_lock_changed || motu->msg ||
+	    snd_motu_register_dsp_message_parser_count_event(motu) > 0)
 		events = EPOLLIN | EPOLLRDNORM;
 	else
 		events = 0;
diff --git a/sound/firewire/motu/motu-register-dsp-message-parser.c b/sound/firewire/motu/motu-register-dsp-message-parser.c
index cda8e6d987cc..cbc06b3b70f6 100644
--- a/sound/firewire/motu/motu-register-dsp-message-parser.c
+++ b/sound/firewire/motu/motu-register-dsp-message-parser.c
@@ -95,6 +95,7 @@ struct msg_parser {
 
 	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)
@@ -122,6 +123,7 @@ int snd_motu_register_dsp_message_parser_init(struct snd_motu *motu)
 	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;
@@ -145,6 +147,7 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 {
 	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;
 
@@ -351,6 +354,9 @@ void snd_motu_register_dsp_message_parser_parse(struct snd_motu *motu, const str
 		}
 	}
 
+	if (pos != parser->push_pos)
+		wake_up(&motu->hwdep_wait);
+
 	spin_unlock_irqrestore(&parser->lock, flags);
 }
 
@@ -375,3 +381,36 @@ void snd_motu_register_dsp_message_parser_copy_parameter(struct snd_motu *motu,
 	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.h b/sound/firewire/motu/motu.h
index 9703d3af59ec..79704ae6a73e 100644
--- a/sound/firewire/motu/motu.h
+++ b/sound/firewire/motu/motu.h
@@ -283,6 +283,8 @@ 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);
-- 
2.30.2

Re: [PATCH 00/11] ALSA: firewire-motu: add ioctl commands to retrieve information in messages delivered by isoc packet

[Takashi Iwai]

On Fri, 15 Oct 2021 10:08:15 +0200,
Takashi Sakamoto wrote:
> 
> Hi,
> 
> The purpose of this patchset is to add message parser to ALSA
> firewire-motu driver so that userspace applications can read information
> in message delivered by isochronous packet as well as PCM frames.
> The message includes information about hardware meter and user action
> over hardware component such as knob, and MIDI message bytes.
> 
> Models in MOTU FireWire series can be categorized to 4 groups in regard
> of message mechanism:
> 
> Group 1. 828 and 896
>  * quadlet message to registered destination address
> Group 2. 828mk2, 896hd, Traveler, 8 pre, Ultralite, 4 pre, and Audio Express
>  * quadlet message to registered destination address
>  * message delivered by isochronous packet
> Group 3. 828mk3, 896mk3, Ultralite mk3, Traveler mk3, and Track 16
>  * quadlet message to registered destination address
>  * message delivered by isochronous packet
>  * block message to registered destination address, including command
> Group 4. V3HD/V4HD
>  * quadlet message to registered destination address
>  * block message to registered destination address
> 
> The patchset is for message delivered by isochronous packet in group 2
> and 3. In Group 2, the message includes information of hardware meter,
> information of user action over hardware component. The model in Group
> 2 is called as 'register DSP' in the patchset since parameters of DSP
> can be configured by asynchronous transaction for register access. In
> Group 3, the message includes information of hardware meter only. The
> model in Group 3 is called as 'command DSP' since software and device
> communicate with commands transferred by asynchronous transaction in
> regard of DSP parameters. Two types of message parser is going to be
> added so that the driver caches images for the information. The cache
> is available for userspace application by ioctl commands newly introduced.
> 
> I note that no control element is added for the hardware meters and user
> actions. It's expected for userspace application to retrieve and parse the
> information of image then operate for user-defined control element set.
> 
> Takashi Sakamoto (11):
>   ALSA: firewire-motu: add message parser to gather meter information in
>     register DSP model
>   ALSA: firewire-motu: add message parser for meter information in
>     command DSP model
>   ALSA: firewire-motu: add ioctl command to read cached hardware meter
>   ALSA: firewire-motu: parse messages for mixer source parameters in
>     register-DSP model
>   ALSA: firewire-motu: parse messages for mixer output parameters in
>     register DSP model
>   ALSA: firewire-motu: parse messages for output parameters in register
>     DSP model
>   ALSA: firewire-motu: parse messages for line input parameters in
>     register DSP model
>   ALSA: firewire-motu: parse messages for input parameters in register
>     DSP model
>   ALSA: firewire-motu: add ioctl command to read cached DSP parameters
>   ALSA: firewire-motu: queue event for parameter change in register DSP
>     model
>   ALSA: firewire-motu: notify event for parameter change in register DSP
>     model

Applied all patches now.  Thanks.


Takashi

Re: [PATCH 00/11] ALSA: firewire-motu: add ioctl commands to retrieve information in messages delivered by isoc packet

[Takashi Sakamoto]

Hi,

On Fri, Oct 15, 2021 at 05:54:13PM +0200, Takashi Iwai wrote:
> On Fri, 15 Oct 2021 10:08:15 +0200,
> Takashi Sakamoto wrote:
> > 
> > Hi,
> > 
> > The purpose of this patchset is to add message parser to ALSA
> > firewire-motu driver so that userspace applications can read information
> > in message delivered by isochronous packet as well as PCM frames.
> > The message includes information about hardware meter and user action
> > over hardware component such as knob, and MIDI message bytes.
> > 
> > Models in MOTU FireWire series can be categorized to 4 groups in regard
> > of message mechanism:
> > 
> > Group 1. 828 and 896
> >  * quadlet message to registered destination address
> > Group 2. 828mk2, 896hd, Traveler, 8 pre, Ultralite, 4 pre, and Audio Express
> >  * quadlet message to registered destination address
> >  * message delivered by isochronous packet
> > Group 3. 828mk3, 896mk3, Ultralite mk3, Traveler mk3, and Track 16
> >  * quadlet message to registered destination address
> >  * message delivered by isochronous packet
> >  * block message to registered destination address, including command
> > Group 4. V3HD/V4HD
> >  * quadlet message to registered destination address
> >  * block message to registered destination address
> > 
> > The patchset is for message delivered by isochronous packet in group 2
> > and 3. In Group 2, the message includes information of hardware meter,
> > information of user action over hardware component. The model in Group
> > 2 is called as 'register DSP' in the patchset since parameters of DSP
> > can be configured by asynchronous transaction for register access. In
> > Group 3, the message includes information of hardware meter only. The
> > model in Group 3 is called as 'command DSP' since software and device
> > communicate with commands transferred by asynchronous transaction in
> > regard of DSP parameters. Two types of message parser is going to be
> > added so that the driver caches images for the information. The cache
> > is available for userspace application by ioctl commands newly introduced.
> > 
> > I note that no control element is added for the hardware meters and user
> > actions. It's expected for userspace application to retrieve and parse the
> > information of image then operate for user-defined control element set.
> > 
> > Takashi Sakamoto (11):
> >   ALSA: firewire-motu: add message parser to gather meter information in
> >     register DSP model
> >   ALSA: firewire-motu: add message parser for meter information in
> >     command DSP model
> >   ALSA: firewire-motu: add ioctl command to read cached hardware meter
> >   ALSA: firewire-motu: parse messages for mixer source parameters in
> >     register-DSP model
> >   ALSA: firewire-motu: parse messages for mixer output parameters in
> >     register DSP model
> >   ALSA: firewire-motu: parse messages for output parameters in register
> >     DSP model
> >   ALSA: firewire-motu: parse messages for line input parameters in
> >     register DSP model
> >   ALSA: firewire-motu: parse messages for input parameters in register
> >     DSP model
> >   ALSA: firewire-motu: add ioctl command to read cached DSP parameters
> >   ALSA: firewire-motu: queue event for parameter change in register DSP
> >     model
> >   ALSA: firewire-motu: notify event for parameter change in register DSP
> >     model
> 
> Applied all patches now.  Thanks.

Thanks for your applying the above patches into your tree. I have some
slight concerns about them. I'd like to ask your opinion.

The snd_firewire_motu_command_dsp_meter structure includes array of 32 bit
storage elements. As I added its documentation, the storage includes
IEEE 764 binary32 values between 0.0 and +1.0. In the patchset I use __u32
type since I can find just a few usage of float type in UAPI header. In
driver side, no floating point arithmetic is used since the float value
is just constructed by gathering messages from target device. In the case,
is it adequate to expose the value as float type in UAPI?

Additionally, current ALSA control interface have no support for control
element with float value, like SNDRV_CTL_ELEM_TYPE_IEEE764_BINARY32. As
long as I know, no discussion about it in the list for recent decades.
Have you ever seen such discussion in the list? (Here I intensionally
ignore that we have several binary expressions for floating point since
I'm just interested in the existence of discussion.)


Regards

Takashi Sakamoto

Re: [PATCH 00/11] ALSA: firewire-motu: add ioctl commands to retrieve information in messages delivered by isoc packet

[Takashi Iwai]

On Sun, 17 Oct 2021 03:22:31 +0200,
Takashi Sakamoto wrote:
> 
> Hi,
> 
> On Fri, Oct 15, 2021 at 05:54:13PM +0200, Takashi Iwai wrote:
> > On Fri, 15 Oct 2021 10:08:15 +0200,
> > Takashi Sakamoto wrote:
> > > 
> > > Hi,
> > > 
> > > The purpose of this patchset is to add message parser to ALSA
> > > firewire-motu driver so that userspace applications can read information
> > > in message delivered by isochronous packet as well as PCM frames.
> > > The message includes information about hardware meter and user action
> > > over hardware component such as knob, and MIDI message bytes.
> > > 
> > > Models in MOTU FireWire series can be categorized to 4 groups in regard
> > > of message mechanism:
> > > 
> > > Group 1. 828 and 896
> > >  * quadlet message to registered destination address
> > > Group 2. 828mk2, 896hd, Traveler, 8 pre, Ultralite, 4 pre, and Audio Express
> > >  * quadlet message to registered destination address
> > >  * message delivered by isochronous packet
> > > Group 3. 828mk3, 896mk3, Ultralite mk3, Traveler mk3, and Track 16
> > >  * quadlet message to registered destination address
> > >  * message delivered by isochronous packet
> > >  * block message to registered destination address, including command
> > > Group 4. V3HD/V4HD
> > >  * quadlet message to registered destination address
> > >  * block message to registered destination address
> > > 
> > > The patchset is for message delivered by isochronous packet in group 2
> > > and 3. In Group 2, the message includes information of hardware meter,
> > > information of user action over hardware component. The model in Group
> > > 2 is called as 'register DSP' in the patchset since parameters of DSP
> > > can be configured by asynchronous transaction for register access. In
> > > Group 3, the message includes information of hardware meter only. The
> > > model in Group 3 is called as 'command DSP' since software and device
> > > communicate with commands transferred by asynchronous transaction in
> > > regard of DSP parameters. Two types of message parser is going to be
> > > added so that the driver caches images for the information. The cache
> > > is available for userspace application by ioctl commands newly introduced.
> > > 
> > > I note that no control element is added for the hardware meters and user
> > > actions. It's expected for userspace application to retrieve and parse the
> > > information of image then operate for user-defined control element set.
> > > 
> > > Takashi Sakamoto (11):
> > >   ALSA: firewire-motu: add message parser to gather meter information in
> > >     register DSP model
> > >   ALSA: firewire-motu: add message parser for meter information in
> > >     command DSP model
> > >   ALSA: firewire-motu: add ioctl command to read cached hardware meter
> > >   ALSA: firewire-motu: parse messages for mixer source parameters in
> > >     register-DSP model
> > >   ALSA: firewire-motu: parse messages for mixer output parameters in
> > >     register DSP model
> > >   ALSA: firewire-motu: parse messages for output parameters in register
> > >     DSP model
> > >   ALSA: firewire-motu: parse messages for line input parameters in
> > >     register DSP model
> > >   ALSA: firewire-motu: parse messages for input parameters in register
> > >     DSP model
> > >   ALSA: firewire-motu: add ioctl command to read cached DSP parameters
> > >   ALSA: firewire-motu: queue event for parameter change in register DSP
> > >     model
> > >   ALSA: firewire-motu: notify event for parameter change in register DSP
> > >     model
> > 
> > Applied all patches now.  Thanks.
> 
> Thanks for your applying the above patches into your tree. I have some
> slight concerns about them. I'd like to ask your opinion.
> 
> The snd_firewire_motu_command_dsp_meter structure includes array of 32 bit
> storage elements. As I added its documentation, the storage includes
> IEEE 764 binary32 values between 0.0 and +1.0. In the patchset I use __u32
> type since I can find just a few usage of float type in UAPI header. In
> driver side, no floating point arithmetic is used since the float value
> is just constructed by gathering messages from target device. In the case,
> is it adequate to expose the value as float type in UAPI?
>
> Additionally, current ALSA control interface have no support for control
> element with float value, like SNDRV_CTL_ELEM_TYPE_IEEE764_BINARY32. As
> long as I know, no discussion about it in the list for recent decades.
> Have you ever seen such discussion in the list? (Here I intensionally
> ignore that we have several binary expressions for floating point since
> I'm just interested in the existence of discussion.)

It's not been proposed, AFAIK.

The biggest concern is that, *if* any reference or calculation of the
float type is required, what to do.  e.g. the kernel has a validation
code for each values (min/max check), and how could it be implemented
for the float type?


thanks,

Takashi

Re: [PATCH 00/11] ALSA: firewire-motu: add ioctl commands to retrieve information in messages delivered by isoc packet

[Takashi Sakamoto]

On Sun, Oct 17, 2021 at 09:02:30AM +0200, Takashi Iwai wrote:
> On Sun, 17 Oct 2021 03:22:31 +0200,
> Takashi Sakamoto wrote:
> > 
> > Hi,
> > 
> > On Fri, Oct 15, 2021 at 05:54:13PM +0200, Takashi Iwai wrote:
> > > On Fri, 15 Oct 2021 10:08:15 +0200,
> > > Takashi Sakamoto wrote:
> > > > 
> > > > Hi,
> > > > 
> > > > The purpose of this patchset is to add message parser to ALSA
> > > > firewire-motu driver so that userspace applications can read information
> > > > in message delivered by isochronous packet as well as PCM frames.
> > > > The message includes information about hardware meter and user action
> > > > over hardware component such as knob, and MIDI message bytes.
> > > > 
> > > > Models in MOTU FireWire series can be categorized to 4 groups in regard
> > > > of message mechanism:
> > > > 
> > > > Group 1. 828 and 896
> > > >  * quadlet message to registered destination address
> > > > Group 2. 828mk2, 896hd, Traveler, 8 pre, Ultralite, 4 pre, and Audio Express
> > > >  * quadlet message to registered destination address
> > > >  * message delivered by isochronous packet
> > > > Group 3. 828mk3, 896mk3, Ultralite mk3, Traveler mk3, and Track 16
> > > >  * quadlet message to registered destination address
> > > >  * message delivered by isochronous packet
> > > >  * block message to registered destination address, including command
> > > > Group 4. V3HD/V4HD
> > > >  * quadlet message to registered destination address
> > > >  * block message to registered destination address
> > > > 
> > > > The patchset is for message delivered by isochronous packet in group 2
> > > > and 3. In Group 2, the message includes information of hardware meter,
> > > > information of user action over hardware component. The model in Group
> > > > 2 is called as 'register DSP' in the patchset since parameters of DSP
> > > > can be configured by asynchronous transaction for register access. In
> > > > Group 3, the message includes information of hardware meter only. The
> > > > model in Group 3 is called as 'command DSP' since software and device
> > > > communicate with commands transferred by asynchronous transaction in
> > > > regard of DSP parameters. Two types of message parser is going to be
> > > > added so that the driver caches images for the information. The cache
> > > > is available for userspace application by ioctl commands newly introduced.
> > > > 
> > > > I note that no control element is added for the hardware meters and user
> > > > actions. It's expected for userspace application to retrieve and parse the
> > > > information of image then operate for user-defined control element set.
> > > > 
> > > > Takashi Sakamoto (11):
> > > >   ALSA: firewire-motu: add message parser to gather meter information in
> > > >     register DSP model
> > > >   ALSA: firewire-motu: add message parser for meter information in
> > > >     command DSP model
> > > >   ALSA: firewire-motu: add ioctl command to read cached hardware meter
> > > >   ALSA: firewire-motu: parse messages for mixer source parameters in
> > > >     register-DSP model
> > > >   ALSA: firewire-motu: parse messages for mixer output parameters in
> > > >     register DSP model
> > > >   ALSA: firewire-motu: parse messages for output parameters in register
> > > >     DSP model
> > > >   ALSA: firewire-motu: parse messages for line input parameters in
> > > >     register DSP model
> > > >   ALSA: firewire-motu: parse messages for input parameters in register
> > > >     DSP model
> > > >   ALSA: firewire-motu: add ioctl command to read cached DSP parameters
> > > >   ALSA: firewire-motu: queue event for parameter change in register DSP
> > > >     model
> > > >   ALSA: firewire-motu: notify event for parameter change in register DSP
> > > >     model
> > > 
> > > Applied all patches now.  Thanks.
> > 
> > Thanks for your applying the above patches into your tree. I have some
> > slight concerns about them. I'd like to ask your opinion.
> > 
> > The snd_firewire_motu_command_dsp_meter structure includes array of 32 bit
> > storage elements. As I added its documentation, the storage includes
> > IEEE 764 binary32 values between 0.0 and +1.0. In the patchset I use __u32
> > type since I can find just a few usage of float type in UAPI header. In
> > driver side, no floating point arithmetic is used since the float value
> > is just constructed by gathering messages from target device. In the case,
> > is it adequate to expose the value as float type in UAPI?
> >
> > Additionally, current ALSA control interface have no support for control
> > element with float value, like SNDRV_CTL_ELEM_TYPE_IEEE764_BINARY32. As
> > long as I know, no discussion about it in the list for recent decades.
> > Have you ever seen such discussion in the list? (Here I intensionally
> > ignore that we have several binary expressions for floating point since
> > I'm just interested in the existence of discussion.)
> 
> It's not been proposed, AFAIK.
> 
> The biggest concern is that, *if* any reference or calculation of the
> float type is required, what to do.  e.g. the kernel has a validation
> code for each values (min/max check), and how could it be implemented
> for the float type?

Indeed. It's probably unavoidable to min/max check and it brings issue
to ALSA control core. It's absolutely out of my scope and thanks for
your indication.

Would I ask you opinion about my concern about firewire UAPI header? Is
it allowed to use float type instead of __u32 type?

> thanks,
> 
> Takashi


Thanks

Takashi Sakamoto

Re: [PATCH 00/11] ALSA: firewire-motu: add ioctl commands to retrieve information in messages delivered by isoc packet

[Takashi Iwai]

On Sun, 17 Oct 2021 11:25:37 +0200,
Takashi Sakamoto wrote:
> 
> Would I ask you opinion about my concern about firewire UAPI header? Is
> it allowed to use float type instead of __u32 type?

I guess the safest way would be like include/uapi/linux/acct.h.
The ifdef KERNEL will be omitted at installation, so user-space would
see only float type while the kernel sees only __u32.


thanks,

Takashi

Re: [PATCH 00/11] ALSA: firewire-motu: add ioctl commands to retrieve information in messages delivered by isoc packet

[Takashi Sakamoto]

Hi,

On Mon, Oct 18, 2021 at 10:05:32AM +0200, Takashi Iwai wrote:
> On Sun, 17 Oct 2021 11:25:37 +0200,
> Takashi Sakamoto wrote:
> > 
> > Would I ask you opinion about my concern about firewire UAPI header? Is
> > it allowed to use float type instead of __u32 type?
> 
> I guess the safest way would be like include/uapi/linux/acct.h.
> The ifdef KERNEL will be omitted at installation, so user-space would
> see only float type while the kernel sees only __u32.

Yes. I've already found the header and it would be the safest, However,
conditional macro sometimes confuses userspace developers...

I decide to keep current usage of __u32 as is. Thanks for your opinion!


Regards

Takashi Sakamoto

Re: [PATCH 00/11] ALSA: firewire-motu: add ioctl commands to retrieve information in messages delivered by isoc packet

[Takashi Iwai]

On Mon, 18 Oct 2021 14:46:54 +0200,
Takashi Sakamoto wrote:
> 
> Hi,
> 
> On Mon, Oct 18, 2021 at 10:05:32AM +0200, Takashi Iwai wrote:
> > On Sun, 17 Oct 2021 11:25:37 +0200,
> > Takashi Sakamoto wrote:
> > > 
> > > Would I ask you opinion about my concern about firewire UAPI header? Is
> > > it allowed to use float type instead of __u32 type?
> > 
> > I guess the safest way would be like include/uapi/linux/acct.h.
> > The ifdef KERNEL will be omitted at installation, so user-space would
> > see only float type while the kernel sees only __u32.
> 
> Yes. I've already found the header and it would be the safest, However,
> conditional macro sometimes confuses userspace developers...

I believe that the ifdef will be dropped automagically during
installing the files, so that user-space will see only float.

You can try to patch and run make headers_install.


Takashi

Re: [PATCH 00/11] ALSA: firewire-motu: add ioctl commands to retrieve information in messages delivered by isoc packet

[Takashi Sakamoto]

Hi,

On Mon, Oct 18, 2021 at 02:57:29PM +0200, Takashi Iwai wrote:
> On Mon, 18 Oct 2021 14:46:54 +0200,
> Takashi Sakamoto wrote:
> > 
> > Hi,
> > 
> > On Mon, Oct 18, 2021 at 10:05:32AM +0200, Takashi Iwai wrote:
> > > On Sun, 17 Oct 2021 11:25:37 +0200,
> > > Takashi Sakamoto wrote:
> > > > 
> > > > Would I ask you opinion about my concern about firewire UAPI header? Is
> > > > it allowed to use float type instead of __u32 type?
> > > 
> > > I guess the safest way would be like include/uapi/linux/acct.h.
> > > The ifdef KERNEL will be omitted at installation, so user-space would
> > > see only float type while the kernel sees only __u32.
> > 
> > Yes. I've already found the header and it would be the safest, However,
> > conditional macro sometimes confuses userspace developers...
> 
> I believe that the ifdef will be dropped automagically during
> installing the files, so that user-space will see only float.
> 
> You can try to patch and run make headers_install.

Oh, I thought that the headers are simply copied when installing...
Indeed, I can find 'scripts/headers_install.sh' does the work in
'headers' make target invoked by the 'headers_install' target.

```
$ tail -n10 include/uapi/sound/firewire.h 
 */
struct snd_firewire_motu_command_dsp_meter {
#ifdef __KERNEL__
	__u32 data[SNDRV_FIREWIRE_MOTU_COMMAND_DSP_METER_COUNT];
#else
	float data[SNDRV_FIREWIRE_MOTU_COMMAND_DSP_METER_COUNT];
#endif
};

#endif /* _UAPI_SOUND_FIREWIRE_H_INCLUDED */
$ make headers
$ tail -n5 usr/include/sound/firewire.h 
 */
struct snd_firewire_motu_command_dsp_meter {
	float data[SNDRV_FIREWIRE_MOTU_COMMAND_DSP_METER_COUNT];
};

#endif /* _SOUND_FIREWIRE_H_INCLUDED */
```

It would be achieved to use different type with the same storage size
between kernel and userspace. After writing some userspace test
applications, I'll post the patch. Thanks for your advice.

> Takashi


Regards

Takashi Sakamoto