1 /* 2 * <linux/usb/audio.h> -- USB Audio definitions. 3 * 4 * Copyright (C) 2006 Thumtronics Pty Ltd. 5 * Developed for Thumtronics by Grey Innovation 6 * Ben Williamson <[email protected]> 7 * 8 * This software is distributed under the terms of the GNU General Public 9 * License ("GPL") version 2, as published by the Free Software Foundation. 10 * 11 * This file holds USB constants and structures defined 12 * by the USB Device Class Definition for Audio Devices. 13 * Comments below reference relevant sections of that document: 14 * 15 * http://www.usb.org/developers/devclass_docs/audio10.pdf 16 */ 17 18 #ifndef __LINUX_USB_AUDIO_H 19 #define __LINUX_USB_AUDIO_H 20 21 #include <linux/types.h> 22 23 /* A.2 Audio Interface Subclass Codes */ 24 #define USB_SUBCLASS_AUDIOCONTROL 0x01 25 #define USB_SUBCLASS_AUDIOSTREAMING 0x02 26 #define USB_SUBCLASS_MIDISTREAMING 0x03 27 28 /* 4.3.2 Class-Specific AC Interface Descriptor */ 29 struct usb_ac_header_descriptor { 30 __u8 bLength; // 8+n 31 __u8 bDescriptorType; // USB_DT_CS_INTERFACE 32 __u8 bDescriptorSubtype; // USB_MS_HEADER 33 __le16 bcdADC; // 0x0100 34 __le16 wTotalLength; // includes Unit and Terminal desc. 35 __u8 bInCollection; // n 36 __u8 baInterfaceNr[]; // [n] 37 } __attribute__ ((packed)); 38 39 #define USB_DT_AC_HEADER_SIZE(n) (8+(n)) 40 41 /* As above, but more useful for defining your own descriptors: */ 42 #define DECLARE_USB_AC_HEADER_DESCRIPTOR(n) \ 43 struct usb_ac_header_descriptor_##n { \ 44 __u8 bLength; \ 45 __u8 bDescriptorType; \ 46 __u8 bDescriptorSubtype; \ 47 __le16 bcdADC; \ 48 __le16 wTotalLength; \ 49 __u8 bInCollection; \ 50 __u8 baInterfaceNr[n]; \ 51 } __attribute__ ((packed)) 52 53 #endif 54