alistair23-linux/include/linux/usb/audio.h
Ben Williamson f2ebf92c9e USB: gmidi: New USB MIDI Gadget class driver.
This driver is glue between the USB gadget interface
and the ALSA MIDI interface. It allows us to appear
as a MIDI Streaming device to a host system on the
other end of a USB cable.

This includes linux/usb/audio.h and linux/usb/midi.h
containing definitions from the relevant USB specifications
for USB audio and USB MIDI devices.

The following changes have been made since the first RFC
posting:

* Bug fixes to endpoint handling.
* Workaround for USB_REQ_SET_CONFIGURATION handling,
  not understood yet.
* Added SND and SND_RAWMIDI dependencies in Kconfig.
* Moved usb_audio.h and usb_midi.h to usb/*.h
* Added module parameters for ALSA card index and id.
* Added module parameters for USB descriptor IDs and strings.
* Removed some unneeded stuff inherited from zero.c, more to go.
* Provide DECLARE_* macros for the variable-length structs.
* Use kmalloc instead of usb_ep_alloc_buffer.
* Limit source to 80 columns.
* Return actual error code instead of -ENOMEM in a few places.

Signed-off-by: Ben Williamson <ben.williamson@greyinnovation.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-27 11:58:52 -07:00

54 lines
1.6 KiB
C

/*
* <linux/usb/audio.h> -- USB Audio definitions.
*
* Copyright (C) 2006 Thumtronics Pty Ltd.
* Developed for Thumtronics by Grey Innovation
* Ben Williamson <ben.williamson@greyinnovation.com>
*
* 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 Audio Devices.
* Comments below reference relevant sections of that document:
*
* http://www.usb.org/developers/devclass_docs/audio10.pdf
*/
#ifndef __LINUX_USB_AUDIO_H
#define __LINUX_USB_AUDIO_H
#include <linux/types.h>
/* A.2 Audio Interface Subclass Codes */
#define USB_SUBCLASS_AUDIOCONTROL 0x01
#define USB_SUBCLASS_AUDIOSTREAMING 0x02
#define USB_SUBCLASS_MIDISTREAMING 0x03
/* 4.3.2 Class-Specific AC Interface Descriptor */
struct usb_ac_header_descriptor {
__u8 bLength; // 8+n
__u8 bDescriptorType; // USB_DT_CS_INTERFACE
__u8 bDescriptorSubtype; // USB_MS_HEADER
__le16 bcdADC; // 0x0100
__le16 wTotalLength; // includes Unit and Terminal desc.
__u8 bInCollection; // n
__u8 baInterfaceNr[]; // [n]
} __attribute__ ((packed));
#define USB_DT_AC_HEADER_SIZE(n) (8+(n))
/* As above, but more useful for defining your own descriptors: */
#define DECLARE_USB_AC_HEADER_DESCRIPTOR(n) \
struct usb_ac_header_descriptor_##n { \
__u8 bLength; \
__u8 bDescriptorType; \
__u8 bDescriptorSubtype; \
__le16 bcdADC; \
__le16 wTotalLength; \
__u8 bInCollection; \
__u8 baInterfaceNr[n]; \
} __attribute__ ((packed))
#endif