include/uapi/sound/firewire.h

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef _UAPI_SOUND_FIREWIRE_H_INCLUDED
#define _UAPI_SOUND_FIREWIRE_H_INCLUDED

#include <linux/ioctl.h>
#include <linux/types.h>

/* events can be read() from the hwdep device */

#define SNDRV_FIREWIRE_EVENT_LOCK_STATUS	0x000010cc
#define SNDRV_FIREWIRE_EVENT_DICE_NOTIFICATION	0xd1ce004e
#define SNDRV_FIREWIRE_EVENT_EFW_RESPONSE	0x4e617475
#define SNDRV_FIREWIRE_EVENT_DIGI00X_MESSAGE	0x746e736c
#define SNDRV_FIREWIRE_EVENT_MOTU_NOTIFICATION	0x64776479
#define SNDRV_FIREWIRE_EVENT_TASCAM_CONTROL	0x7473636d

struct snd_firewire_event_common {
	unsigned int type; /* SNDRV_FIREWIRE_EVENT_xxx */
};

struct snd_firewire_event_lock_status {
	unsigned int type;
	unsigned int status; /* 0/1 = unlocked/locked */
};

struct snd_firewire_event_dice_notification {
	unsigned int type;
	unsigned int notification; /* DICE-specific bits */
};

#define SND_EFW_TRANSACTION_USER_SEQNUM_MAX	((__u32)((__u16)~0) - 1)
/* each field should be in big endian */
struct snd_efw_transaction {
	__be32 length;
	__be32 version;
	__be32 seqnum;
	__be32 category;
	__be32 command;
	__be32 status;
	__be32 params[0];
};
struct snd_firewire_event_efw_response {
	unsigned int type;
	__be32 response[0];	/* some responses */
};

struct snd_firewire_event_digi00x_message {
	unsigned int type;
	__u32 message;	/* Digi00x-specific message */
};

struct snd_firewire_event_motu_notification {
	unsigned int type;
	__u32 message;	/* MOTU-specific bits. */
};

struct snd_firewire_tascam_change {
	unsigned int index;
	__be32 before;
	__be32 after;
};

struct snd_firewire_event_tascam_control {
	unsigned int type;
	struct snd_firewire_tascam_change changes[0];
};

union snd_firewire_event {
	struct snd_firewire_event_common            common;
	struct snd_firewire_event_lock_status       lock_status;
	struct snd_firewire_event_dice_notification dice_notification;
	struct snd_firewire_event_efw_response      efw_response;
	struct snd_firewire_event_digi00x_message   digi00x_message;
	struct snd_firewire_event_tascam_control    tascam_control;
	struct snd_firewire_event_motu_notification motu_notification;
};


#define SNDRV_FIREWIRE_IOCTL_GET_INFO _IOR('H', 0xf8, struct snd_firewire_get_info)
#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_TYPE_DICE	1
#define SNDRV_FIREWIRE_TYPE_FIREWORKS	2
#define SNDRV_FIREWIRE_TYPE_BEBOB	3
#define SNDRV_FIREWIRE_TYPE_OXFW	4
#define SNDRV_FIREWIRE_TYPE_DIGI00X	5
#define SNDRV_FIREWIRE_TYPE_TASCAM	6
#define SNDRV_FIREWIRE_TYPE_MOTU	7
#define SNDRV_FIREWIRE_TYPE_FIREFACE	8

struct snd_firewire_get_info {
	unsigned int type; /* SNDRV_FIREWIRE_TYPE_xxx */
	unsigned int card; /* same as fw_cdev_get_info.card */
	unsigned char guid[8];
	char device_name[16]; /* device node in /dev */
};

/*
 * SNDRV_FIREWIRE_IOCTL_LOCK prevents the driver from streaming.
 * Returns -EBUSY if the driver is already streaming.
 */

#define SNDRV_FIREWIRE_TASCAM_STATE_COUNT	64

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 */