1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 /*
3  * <linux/usb/midi.h> -- USB MIDI definitions.
4  *
5  * Copyright (C) 2006 Thumtronics Pty Ltd.
6  * Developed for Thumtronics by Grey Innovation
7  * Ben Williamson <ben.williamson@greyinnovation.com>
8  *
9  * This software is distributed under the terms of the GNU General Public
10  * License ("GPL") version 2, as published by the Free Software Foundation.
11  *
12  * This file holds USB constants and structures defined
13  * by the USB Device Class Definition for MIDI Devices.
14  * Comments below reference relevant sections of that document:
15  *
16  * http://www.usb.org/developers/devclass_docs/midi10.pdf
17  */
18 
19 #ifndef __LINUX_USB_MIDI_H
20 #define __LINUX_USB_MIDI_H
21 
22 #include <linux/types.h>
23 
24 /* A.1  MS Class-Specific Interface Descriptor Subtypes */
25 #define USB_MS_HEADER		0x01
26 #define USB_MS_MIDI_IN_JACK	0x02
27 #define USB_MS_MIDI_OUT_JACK	0x03
28 #define USB_MS_ELEMENT		0x04
29 
30 /* A.2  MS Class-Specific Endpoint Descriptor Subtypes */
31 #define USB_MS_GENERAL		0x01
32 
33 /* A.3  MS MIDI IN and OUT Jack Types */
34 #define USB_MS_EMBEDDED		0x01
35 #define USB_MS_EXTERNAL		0x02
36 
37 /* 6.1.2.1  Class-Specific MS Interface Header Descriptor */
38 struct usb_ms_header_descriptor {
39 	__u8  bLength;
40 	__u8  bDescriptorType;
41 	__u8  bDescriptorSubtype;
42 	__le16 bcdMSC;
43 	__le16 wTotalLength;
44 } __attribute__ ((packed));
45 
46 #define USB_DT_MS_HEADER_SIZE	7
47 
48 /* 6.1.2.2  MIDI IN Jack Descriptor */
49 struct usb_midi_in_jack_descriptor {
50 	__u8  bLength;
51 	__u8  bDescriptorType;		/* USB_DT_CS_INTERFACE */
52 	__u8  bDescriptorSubtype;	/* USB_MS_MIDI_IN_JACK */
53 	__u8  bJackType;		/* USB_MS_EMBEDDED/EXTERNAL */
54 	__u8  bJackID;
55 	__u8  iJack;
56 } __attribute__ ((packed));
57 
58 #define USB_DT_MIDI_IN_SIZE	6
59 
60 struct usb_midi_source_pin {
61 	__u8  baSourceID;
62 	__u8  baSourcePin;
63 } __attribute__ ((packed));
64 
65 /* 6.1.2.3  MIDI OUT Jack Descriptor */
66 struct usb_midi_out_jack_descriptor {
67 	__u8  bLength;
68 	__u8  bDescriptorType;		/* USB_DT_CS_INTERFACE */
69 	__u8  bDescriptorSubtype;	/* USB_MS_MIDI_OUT_JACK */
70 	__u8  bJackType;		/* USB_MS_EMBEDDED/EXTERNAL */
71 	__u8  bJackID;
72 	__u8  bNrInputPins;		/* p */
73 	struct usb_midi_source_pin pins[]; /* [p] */
74 	/*__u8  iJack;  -- omitted due to variable-sized pins[] */
75 } __attribute__ ((packed));
76 
77 #define USB_DT_MIDI_OUT_SIZE(p)	(7 + 2 * (p))
78 
79 /* As above, but more useful for defining your own descriptors: */
80 #define DECLARE_USB_MIDI_OUT_JACK_DESCRIPTOR(p)			\
81 struct usb_midi_out_jack_descriptor_##p {			\
82 	__u8  bLength;						\
83 	__u8  bDescriptorType;					\
84 	__u8  bDescriptorSubtype;				\
85 	__u8  bJackType;					\
86 	__u8  bJackID;						\
87 	__u8  bNrInputPins;					\
88 	struct usb_midi_source_pin pins[p];			\
89 	__u8  iJack;						\
90 } __attribute__ ((packed))
91 
92 /* 6.2.2  Class-Specific MS Bulk Data Endpoint Descriptor */
93 struct usb_ms_endpoint_descriptor {
94 	__u8  bLength;			/* 4+n */
95 	__u8  bDescriptorType;		/* USB_DT_CS_ENDPOINT */
96 	__u8  bDescriptorSubtype;	/* USB_MS_GENERAL */
97 	__u8  bNumEmbMIDIJack;		/* n */
98 	__u8  baAssocJackID[];		/* [n] */
99 } __attribute__ ((packed));
100 
101 #define USB_DT_MS_ENDPOINT_SIZE(n)	(4 + (n))
102 
103 /* As above, but more useful for defining your own descriptors: */
104 #define DECLARE_USB_MS_ENDPOINT_DESCRIPTOR(n)			\
105 struct usb_ms_endpoint_descriptor_##n {				\
106 	__u8  bLength;						\
107 	__u8  bDescriptorType;					\
108 	__u8  bDescriptorSubtype;				\
109 	__u8  bNumEmbMIDIJack;					\
110 	__u8  baAssocJackID[n];					\
111 } __attribute__ ((packed))
112 
113 #endif /* __LINUX_USB_MIDI_H */
114