midi.h

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/*
 * <linux/usb/midi.h> -- USB MIDI definitions.
 *
 * Copyright (C) 2006 Thumtronics Pty Ltd.
 * Developed for Thumtronics by Grey Innovation
 * Ben Williamson <[email protected]>
 *
 * This software is distributed under the terms of the GNU General Public
 * License ("GPL") version 2, as published by the Free Software Foundation.
 *
 * This file holds USB constants and structures defined
 * by the USB Device Class Definition for MIDI Devices.
 * Comments below reference relevant sections of that document:
 *
 * http://www.usb.org/developers/devclass_docs/midi10.pdf
 */

#ifndef __LINUX_USB_MIDI_H
#define __LINUX_USB_MIDI_H

#include <linux/types.h>

/* A.1  MS Class-Specific Interface Descriptor Subtypes */
#define USB_MS_HEADER       0x01
#define USB_MS_MIDI_IN_JACK 0x02
#define USB_MS_MIDI_OUT_JACK    0x03
#define USB_MS_ELEMENT      0x04

/* A.2  MS Class-Specific Endpoint Descriptor Subtypes */
#define USB_MS_GENERAL      0x01

/* A.3  MS MIDI IN and OUT Jack Types */
#define USB_MS_EMBEDDED     0x01
#define USB_MS_EXTERNAL     0x02

/* 6.1.2.1  Class-Specific MS Interface Header Descriptor */
struct usb_ms_header_descriptor {
    __u8  bLength;
    __u8  bDescriptorType;
    __u8  bDescriptorSubtype;
    __le16 bcdMSC;
    __le16 wTotalLength;
} __attribute__ ((packed));

#define USB_DT_MS_HEADER_SIZE   7

/* 6.1.2.2  MIDI IN Jack Descriptor */
struct usb_midi_in_jack_descriptor {
    __u8  bLength;
    __u8  bDescriptorType;      /* USB_DT_CS_INTERFACE */
    __u8  bDescriptorSubtype;   /* USB_MS_MIDI_IN_JACK */
    __u8  bJackType;        /* USB_MS_EMBEDDED/EXTERNAL */
    __u8  bJackID;
    __u8  iJack;
} __attribute__ ((packed));

#define USB_DT_MIDI_IN_SIZE 6

struct usb_midi_source_pin {
    __u8  baSourceID;
    __u8  baSourcePin;
} __attribute__ ((packed));

/* 6.1.2.3  MIDI OUT Jack Descriptor */
struct usb_midi_out_jack_descriptor {
    __u8  bLength;
    __u8  bDescriptorType;      /* USB_DT_CS_INTERFACE */
    __u8  bDescriptorSubtype;   /* USB_MS_MIDI_OUT_JACK */
    __u8  bJackType;        /* USB_MS_EMBEDDED/EXTERNAL */
    __u8  bJackID;
    __u8  bNrInputPins;     /* p */
    struct usb_midi_source_pin pins[]; /* [p] */
    /*__u8  iJack;  -- omitted due to variable-sized pins[] */
} __attribute__ ((packed));

#define USB_DT_MIDI_OUT_SIZE(p) (7 + 2 * (p))

/* As above, but more useful for defining your own descriptors: */
#define DECLARE_USB_MIDI_OUT_JACK_DESCRIPTOR(p)         \
struct usb_midi_out_jack_descriptor_##p {           \
    __u8  bLength;                      \
    __u8  bDescriptorType;                  \
    __u8  bDescriptorSubtype;               \
    __u8  bJackType;                    \
    __u8  bJackID;                      \
    __u8  bNrInputPins;                 \
    struct usb_midi_source_pin pins[p];         \
    __u8  iJack;                        \
} __attribute__ ((packed))

/* 6.2.2  Class-Specific MS Bulk Data Endpoint Descriptor */
struct usb_ms_endpoint_descriptor {
    __u8  bLength;          /* 4+n */
    __u8  bDescriptorType;      /* USB_DT_CS_ENDPOINT */
    __u8  bDescriptorSubtype;   /* USB_MS_GENERAL */
    __u8  bNumEmbMIDIJack;      /* n */
    __u8  baAssocJackID[];      /* [n] */
} __attribute__ ((packed));

#define USB_DT_MS_ENDPOINT_SIZE(n)  (4 + (n))

/* As above, but more useful for defining your own descriptors: */
#define DECLARE_USB_MS_ENDPOINT_DESCRIPTOR(n)           \
struct usb_ms_endpoint_descriptor_##n {             \
    __u8  bLength;                      \
    __u8  bDescriptorType;                  \
    __u8  bDescriptorSubtype;               \
    __u8  bNumEmbMIDIJack;                  \
    __u8  baAssocJackID[n];                 \
} __attribute__ ((packed))

#endif /* __LINUX_USB_MIDI_H */