include/linux/usb_ch9.h - kernel/msm - Gitiles

 /*
  * This file holds USB constants and structures that are needed for USB
  * device APIs.  These are used by the USB device model, which is defined
  * in chapter 9 of the USB 2.0 specification.  Linux has several APIs in C
  * that need these:
  *
  * - the master/host side Linux-USB kernel driver API;
  * - the "usbfs" user space API; and
  * - (eventually) a Linux "gadget" slave/device side driver API.
  *
  * USB 2.0 adds an additional "On The Go" (OTG) mode, which lets systems
  * act either as a USB master/host or as a USB slave/device.  That means
  * the master and slave side APIs will benefit from working well together.
  */

 #ifndef __LINUX_USB_CH9_H
 #define __LINUX_USB_CH9_H

 #include <asm/types.h>		/* __u8 etc */

 /*-------------------------------------------------------------------------*/

 /* CONTROL REQUEST SUPPORT */

 /*
  * USB directions
  *
  * This bit flag is used in endpoint descriptors' bEndpointAddress field.
  * It's also one of three fields in control requests bRequestType.
  */
 #define USB_DIR_OUT			0		/* to device */
 #define USB_DIR_IN			0x80		/* to host */

 /*
  * USB types, the second of three bRequestType fields
  */
 #define USB_TYPE_MASK			(0x03 << 5)
 #define USB_TYPE_STANDARD		(0x00 << 5)
 #define USB_TYPE_CLASS			(0x01 << 5)
 #define USB_TYPE_VENDOR			(0x02 << 5)
 #define USB_TYPE_RESERVED		(0x03 << 5)

 /*
  * USB recipients, the third of three bRequestType fields
  */
 #define USB_RECIP_MASK			0x1f
 #define USB_RECIP_DEVICE		0x00
 #define USB_RECIP_INTERFACE		0x01
 #define USB_RECIP_ENDPOINT		0x02
 #define USB_RECIP_OTHER			0x03

 /*
  * Standard requests, for the bRequest field of a SETUP packet.
  *
  * These are qualified by the bRequestType field, so that for example
  * TYPE_CLASS or TYPE_VENDOR specific feature flags could be retrieved
  * by a GET_STATUS request.
  */
 #define USB_REQ_GET_STATUS		0x00
 #define USB_REQ_CLEAR_FEATURE		0x01
 #define USB_REQ_SET_FEATURE		0x03
 #define USB_REQ_SET_ADDRESS		0x05
 #define USB_REQ_GET_DESCRIPTOR		0x06
 #define USB_REQ_SET_DESCRIPTOR		0x07
 #define USB_REQ_GET_CONFIGURATION	0x08
 #define USB_REQ_SET_CONFIGURATION	0x09
 #define USB_REQ_GET_INTERFACE		0x0A
 #define USB_REQ_SET_INTERFACE		0x0B
 #define USB_REQ_SYNCH_FRAME		0x0C

 /*
  * USB feature flags are written using USB_REQ_{CLEAR,SET}_FEATURE, and
  * are read as a bit array returned by USB_REQ_GET_STATUS.  (So there
  * are at most sixteen features of each type.)
  */
 #define USB_DEVICE_SELF_POWERED		0	/* (read only) */
 #define USB_DEVICE_REMOTE_WAKEUP	1	/* dev may initiate wakeup */
 #define USB_DEVICE_TEST_MODE		2	/* (high speed only) */
 #define USB_DEVICE_B_HNP_ENABLE		3	/* dev may initiate HNP */
 #define USB_DEVICE_A_HNP_SUPPORT	4	/* RH port supports HNP */
 #define USB_DEVICE_A_ALT_HNP_SUPPORT	5	/* other RH port does */
 #define USB_DEVICE_DEBUG_MODE		6	/* (special devices only) */

 #define USB_ENDPOINT_HALT		0	/* IN/OUT will STALL */


 /**
  * struct usb_ctrlrequest - SETUP data for a USB device control request
  * @bRequestType: matches the USB bmRequestType field
  * @bRequest: matches the USB bRequest field
  * @wValue: matches the USB wValue field (le16 byte order)
  * @wIndex: matches the USB wIndex field (le16 byte order)
  * @wLength: matches the USB wLength field (le16 byte order)
  *
  * This structure is used to send control requests to a USB device.  It matches
  * the different fields of the USB 2.0 Spec section 9.3, table 9-2.  See the
  * USB spec for a fuller description of the different fields, and what they are
  * used for.
  *
  * Note that the driver for any interface can issue control requests.
  * For most devices, interfaces don't coordinate with each other, so
  * such requests may be made at any time.
  */
 struct usb_ctrlrequest {
 	__u8 bRequestType;
 	__u8 bRequest;
 	__le16 wValue;
 	__le16 wIndex;
 	__le16 wLength;
 } __attribute__ ((packed));

 /*-------------------------------------------------------------------------*/

 /*
  * STANDARD DESCRIPTORS ... as returned by GET_DESCRIPTOR, or
  * (rarely) accepted by SET_DESCRIPTOR.
  *
  * Note that all multi-byte values here are encoded in little endian
  * byte order "on the wire".  But when exposed through Linux-USB APIs,
  * they've been converted to cpu byte order.
  */

 /*
  * Descriptor types ... USB 2.0 spec table 9.5
  */
 #define USB_DT_DEVICE			0x01
 #define USB_DT_CONFIG			0x02
 #define USB_DT_STRING			0x03
 #define USB_DT_INTERFACE		0x04
 #define USB_DT_ENDPOINT			0x05
 #define USB_DT_DEVICE_QUALIFIER		0x06
 #define USB_DT_OTHER_SPEED_CONFIG	0x07
 #define USB_DT_INTERFACE_POWER		0x08
 /* these are from a minor usb 2.0 revision (ECN) */
 #define USB_DT_OTG			0x09
 #define USB_DT_DEBUG			0x0a
 #define USB_DT_INTERFACE_ASSOCIATION	0x0b

 /* conventional codes for class-specific descriptors */
 #define USB_DT_CS_DEVICE		0x21
 #define USB_DT_CS_CONFIG		0x22
 #define USB_DT_CS_STRING		0x23
 #define USB_DT_CS_INTERFACE		0x24
 #define USB_DT_CS_ENDPOINT		0x25

 /* All standard descriptors have these 2 fields at the beginning */
 struct usb_descriptor_header {
 	__u8  bLength;
 	__u8  bDescriptorType;
 } __attribute__ ((packed));


 /*-------------------------------------------------------------------------*/

 /* USB_DT_DEVICE: Device descriptor */
 struct usb_device_descriptor {
 	__u8  bLength;
 	__u8  bDescriptorType;

 	__le16 bcdUSB;
 	__u8  bDeviceClass;
 	__u8  bDeviceSubClass;
 	__u8  bDeviceProtocol;
 	__u8  bMaxPacketSize0;
 	__le16 idVendor;
 	__le16 idProduct;
 	__le16 bcdDevice;
 	__u8  iManufacturer;
 	__u8  iProduct;
 	__u8  iSerialNumber;
 	__u8  bNumConfigurations;
 } __attribute__ ((packed));

 #define USB_DT_DEVICE_SIZE		18


 /*
  * Device and/or Interface Class codes
  * as found in bDeviceClass or bInterfaceClass
  * and defined by www.usb.org documents
  */
 #define USB_CLASS_PER_INTERFACE		0	/* for DeviceClass */
 #define USB_CLASS_AUDIO			1
 #define USB_CLASS_COMM			2
 #define USB_CLASS_HID			3
 #define USB_CLASS_PHYSICAL		5
 #define USB_CLASS_STILL_IMAGE		6
 #define USB_CLASS_PRINTER		7
 #define USB_CLASS_MASS_STORAGE		8
 #define USB_CLASS_HUB			9
 #define USB_CLASS_CDC_DATA		0x0a
 #define USB_CLASS_CSCID			0x0b	/* chip+ smart card */
 #define USB_CLASS_CONTENT_SEC		0x0d	/* content security */
 #define USB_CLASS_VIDEO			0x0e
 #define USB_CLASS_APP_SPEC		0xfe
 #define USB_CLASS_VENDOR_SPEC		0xff

 /*-------------------------------------------------------------------------*/

 /* USB_DT_CONFIG: Configuration descriptor information.
  *
  * USB_DT_OTHER_SPEED_CONFIG is the same descriptor, except that the
  * descriptor type is different.  Highspeed-capable devices can look
  * different depending on what speed they're currently running.  Only
  * devices with a USB_DT_DEVICE_QUALIFIER have any OTHER_SPEED_CONFIG
  * descriptors.
  */
 struct usb_config_descriptor {
 	__u8  bLength;
 	__u8  bDescriptorType;

 	__le16 wTotalLength;
 	__u8  bNumInterfaces;
 	__u8  bConfigurationValue;
 	__u8  iConfiguration;
 	__u8  bmAttributes;
 	__u8  bMaxPower;
 } __attribute__ ((packed));

 #define USB_DT_CONFIG_SIZE		9

 /* from config descriptor bmAttributes */
 #define USB_CONFIG_ATT_ONE		(1 << 7)	/* must be set */
 #define USB_CONFIG_ATT_SELFPOWER	(1 << 6)	/* self powered */
 #define USB_CONFIG_ATT_WAKEUP		(1 << 5)	/* can wakeup */

 /*-------------------------------------------------------------------------*/

 /* USB_DT_STRING: String descriptor */
 struct usb_string_descriptor {
 	__u8  bLength;
 	__u8  bDescriptorType;

 	__le16 wData[1];		/* UTF-16LE encoded */
 } __attribute__ ((packed));

 /* note that "string" zero is special, it holds language codes that
  * the device supports, not Unicode characters.
  */

 /*-------------------------------------------------------------------------*/

 /* USB_DT_INTERFACE: Interface descriptor */
 struct usb_interface_descriptor {
 	__u8  bLength;
 	__u8  bDescriptorType;

 	__u8  bInterfaceNumber;
 	__u8  bAlternateSetting;
 	__u8  bNumEndpoints;
 	__u8  bInterfaceClass;
 	__u8  bInterfaceSubClass;
 	__u8  bInterfaceProtocol;
 	__u8  iInterface;
 } __attribute__ ((packed));

 #define USB_DT_INTERFACE_SIZE		9

 /*-------------------------------------------------------------------------*/

 /* USB_DT_ENDPOINT: Endpoint descriptor */
 struct usb_endpoint_descriptor {
 	__u8  bLength;
 	__u8  bDescriptorType;

 	__u8  bEndpointAddress;
 	__u8  bmAttributes;
 	__le16 wMaxPacketSize;
 	__u8  bInterval;

 	// NOTE:  these two are _only_ in audio endpoints.
 	// use USB_DT_ENDPOINT*_SIZE in bLength, not sizeof.
 	__u8  bRefresh;
 	__u8  bSynchAddress;
 } __attribute__ ((packed));

 #define USB_DT_ENDPOINT_SIZE		7
 #define USB_DT_ENDPOINT_AUDIO_SIZE	9	/* Audio extension */


 /*
  * Endpoints
  */
 #define USB_ENDPOINT_NUMBER_MASK	0x0f	/* in bEndpointAddress */
 #define USB_ENDPOINT_DIR_MASK		0x80

 #define USB_ENDPOINT_XFERTYPE_MASK	0x03	/* in bmAttributes */
 #define USB_ENDPOINT_XFER_CONTROL	0
 #define USB_ENDPOINT_XFER_ISOC		1
 #define USB_ENDPOINT_XFER_BULK		2
 #define USB_ENDPOINT_XFER_INT		3


 /*-------------------------------------------------------------------------*/

 /* USB_DT_DEVICE_QUALIFIER: Device Qualifier descriptor */
 struct usb_qualifier_descriptor {
 	__u8  bLength;
 	__u8  bDescriptorType;

 	__le16 bcdUSB;
 	__u8  bDeviceClass;
 	__u8  bDeviceSubClass;
 	__u8  bDeviceProtocol;
 	__u8  bMaxPacketSize0;
 	__u8  bNumConfigurations;
 	__u8  bRESERVED;
 } __attribute__ ((packed));


 /*-------------------------------------------------------------------------*/

 /* USB_DT_OTG (from OTG 1.0a supplement) */
 struct usb_otg_descriptor {
 	__u8  bLength;
 	__u8  bDescriptorType;

 	__u8  bmAttributes;	/* support for HNP, SRP, etc */
 } __attribute__ ((packed));

 /* from usb_otg_descriptor.bmAttributes */
 #define USB_OTG_SRP		(1 << 0)
 #define USB_OTG_HNP		(1 << 1)	/* swap host/device roles */

 /*-------------------------------------------------------------------------*/

 /* USB_DT_DEBUG:  for special highspeed devices, replacing serial console */
 struct usb_debug_descriptor {
 	__u8  bLength;
 	__u8  bDescriptorType;

 	/* bulk endpoints with 8 byte maxpacket */
 	__u8  bDebugInEndpoint;
 	__u8  bDebugOutEndpoint;
 };

 /*-------------------------------------------------------------------------*/

 /* USB_DT_INTERFACE_ASSOCIATION: groups interfaces */
 struct usb_interface_assoc_descriptor {
 	__u8  bLength;
 	__u8  bDescriptorType;

 	__u8  bFirstInterface;
 	__u8  bInterfaceCount;
 	__u8  bFunctionClass;
 	__u8  bFunctionSubClass;
 	__u8  bFunctionProtocol;
 	__u8  iFunction;
 } __attribute__ ((packed));


 /*-------------------------------------------------------------------------*/

 /* USB 2.0 defines three speeds, here's how Linux identifies them */

 enum usb_device_speed {
 	USB_SPEED_UNKNOWN = 0,			/* enumerating */
 	USB_SPEED_LOW, USB_SPEED_FULL,		/* usb 1.1 */
 	USB_SPEED_HIGH				/* usb 2.0 */
 };

 enum usb_device_state {
 	/* NOTATTACHED isn't in the USB spec, and this state acts
 	 * the same as ATTACHED ... but it's clearer this way.
 	 */
 	USB_STATE_NOTATTACHED = 0,

 	/* the chapter 9 device states */
 	USB_STATE_ATTACHED,
 	USB_STATE_POWERED,
 	USB_STATE_DEFAULT,			/* limited function */
 	USB_STATE_ADDRESS,
 	USB_STATE_CONFIGURED,			/* most functions */

 	USB_STATE_SUSPENDED

 	/* NOTE:  there are actually four different SUSPENDED
 	 * states, returning to POWERED, DEFAULT, ADDRESS, or
 	 * CONFIGURED respectively when SOF tokens flow again.
 	 */
 };

 #endif	/* __LINUX_USB_CH9_H */
	/*
	* This file holds USB constants and structures that are needed for USB
	* device APIs. These are used by the USB device model, which is defined
	* in chapter 9 of the USB 2.0 specification. Linux has several APIs in C
	* that need these:
	*
	* - the master/host side Linux-USB kernel driver API;
	* - the "usbfs" user space API; and
	* - (eventually) a Linux "gadget" slave/device side driver API.
	*
	* USB 2.0 adds an additional "On The Go" (OTG) mode, which lets systems
	* act either as a USB master/host or as a USB slave/device. That means
	* the master and slave side APIs will benefit from working well together.
	*/

	#ifndef __LINUX_USB_CH9_H
	#define __LINUX_USB_CH9_H

	#include <asm/types.h> /* __u8 etc */

	/-------------------------------------------------------------------------/

	/* CONTROL REQUEST SUPPORT */

	/*
	* USB directions
	*
	* This bit flag is used in endpoint descriptors' bEndpointAddress field.
	* It's also one of three fields in control requests bRequestType.
	*/
	#define USB_DIR_OUT 0 /* to device */
	#define USB_DIR_IN 0x80 /* to host */

	/*
	* USB types, the second of three bRequestType fields
	*/
	#define USB_TYPE_MASK (0x03 << 5)
	#define USB_TYPE_STANDARD (0x00 << 5)
	#define USB_TYPE_CLASS (0x01 << 5)
	#define USB_TYPE_VENDOR (0x02 << 5)
	#define USB_TYPE_RESERVED (0x03 << 5)

	/*
	* USB recipients, the third of three bRequestType fields
	*/
	#define USB_RECIP_MASK 0x1f
	#define USB_RECIP_DEVICE 0x00
	#define USB_RECIP_INTERFACE 0x01
	#define USB_RECIP_ENDPOINT 0x02
	#define USB_RECIP_OTHER 0x03

	/*
	* Standard requests, for the bRequest field of a SETUP packet.
	*
	* These are qualified by the bRequestType field, so that for example
	* TYPE_CLASS or TYPE_VENDOR specific feature flags could be retrieved
	* by a GET_STATUS request.
	*/
	#define USB_REQ_GET_STATUS 0x00
	#define USB_REQ_CLEAR_FEATURE 0x01
	#define USB_REQ_SET_FEATURE 0x03
	#define USB_REQ_SET_ADDRESS 0x05
	#define USB_REQ_GET_DESCRIPTOR 0x06
	#define USB_REQ_SET_DESCRIPTOR 0x07
	#define USB_REQ_GET_CONFIGURATION 0x08
	#define USB_REQ_SET_CONFIGURATION 0x09
	#define USB_REQ_GET_INTERFACE 0x0A
	#define USB_REQ_SET_INTERFACE 0x0B
	#define USB_REQ_SYNCH_FRAME 0x0C

	/*
	* USB feature flags are written using USB_REQ_{CLEAR,SET}_FEATURE, and
	* are read as a bit array returned by USB_REQ_GET_STATUS. (So there
	* are at most sixteen features of each type.)
	*/
	#define USB_DEVICE_SELF_POWERED 0 /* (read only) */
	#define USB_DEVICE_REMOTE_WAKEUP 1 /* dev may initiate wakeup */
	#define USB_DEVICE_TEST_MODE 2 /* (high speed only) */
	#define USB_DEVICE_B_HNP_ENABLE 3 /* dev may initiate HNP */
	#define USB_DEVICE_A_HNP_SUPPORT 4 /* RH port supports HNP */
	#define USB_DEVICE_A_ALT_HNP_SUPPORT 5 /* other RH port does */
	#define USB_DEVICE_DEBUG_MODE 6 /* (special devices only) */

	#define USB_ENDPOINT_HALT 0 /* IN/OUT will STALL */


	/**
	* struct usb_ctrlrequest - SETUP data for a USB device control request
	* @bRequestType: matches the USB bmRequestType field
	* @bRequest: matches the USB bRequest field
	* @wValue: matches the USB wValue field (le16 byte order)
	* @wIndex: matches the USB wIndex field (le16 byte order)
	* @wLength: matches the USB wLength field (le16 byte order)
	*
	* This structure is used to send control requests to a USB device. It matches
	* the different fields of the USB 2.0 Spec section 9.3, table 9-2. See the
	* USB spec for a fuller description of the different fields, and what they are
	* used for.
	*
	* Note that the driver for any interface can issue control requests.
	* For most devices, interfaces don't coordinate with each other, so
	* such requests may be made at any time.
	*/
	struct usb_ctrlrequest {
	__u8 bRequestType;
	__u8 bRequest;
	__le16 wValue;
	__le16 wIndex;
	__le16 wLength;
	} __attribute__ ((packed));

	/-------------------------------------------------------------------------/

	/*
	* STANDARD DESCRIPTORS ... as returned by GET_DESCRIPTOR, or
	* (rarely) accepted by SET_DESCRIPTOR.
	*
	* Note that all multi-byte values here are encoded in little endian
	* byte order "on the wire". But when exposed through Linux-USB APIs,
	* they've been converted to cpu byte order.
	*/

	/*
	* Descriptor types ... USB 2.0 spec table 9.5
	*/
	#define USB_DT_DEVICE 0x01
	#define USB_DT_CONFIG 0x02
	#define USB_DT_STRING 0x03
	#define USB_DT_INTERFACE 0x04
	#define USB_DT_ENDPOINT 0x05
	#define USB_DT_DEVICE_QUALIFIER 0x06
	#define USB_DT_OTHER_SPEED_CONFIG 0x07
	#define USB_DT_INTERFACE_POWER 0x08
	/* these are from a minor usb 2.0 revision (ECN) */
	#define USB_DT_OTG 0x09
	#define USB_DT_DEBUG 0x0a
	#define USB_DT_INTERFACE_ASSOCIATION 0x0b

	/* conventional codes for class-specific descriptors */
	#define USB_DT_CS_DEVICE 0x21
	#define USB_DT_CS_CONFIG 0x22
	#define USB_DT_CS_STRING 0x23
	#define USB_DT_CS_INTERFACE 0x24
	#define USB_DT_CS_ENDPOINT 0x25

	/* All standard descriptors have these 2 fields at the beginning */
	struct usb_descriptor_header {
	__u8 bLength;
	__u8 bDescriptorType;
	} __attribute__ ((packed));


	/-------------------------------------------------------------------------/

	/* USB_DT_DEVICE: Device descriptor */
	struct usb_device_descriptor {
	__u8 bLength;
	__u8 bDescriptorType;

	__le16 bcdUSB;
	__u8 bDeviceClass;
	__u8 bDeviceSubClass;
	__u8 bDeviceProtocol;
	__u8 bMaxPacketSize0;
	__le16 idVendor;
	__le16 idProduct;
	__le16 bcdDevice;
	__u8 iManufacturer;
	__u8 iProduct;
	__u8 iSerialNumber;
	__u8 bNumConfigurations;
	} __attribute__ ((packed));

	#define USB_DT_DEVICE_SIZE 18


	/*
	* Device and/or Interface Class codes
	* as found in bDeviceClass or bInterfaceClass
	* and defined by www.usb.org documents
	*/
	#define USB_CLASS_PER_INTERFACE 0 /* for DeviceClass */
	#define USB_CLASS_AUDIO 1
	#define USB_CLASS_COMM 2
	#define USB_CLASS_HID 3
	#define USB_CLASS_PHYSICAL 5
	#define USB_CLASS_STILL_IMAGE 6
	#define USB_CLASS_PRINTER 7
	#define USB_CLASS_MASS_STORAGE 8
	#define USB_CLASS_HUB 9
	#define USB_CLASS_CDC_DATA 0x0a
	#define USB_CLASS_CSCID 0x0b /* chip+ smart card */
	#define USB_CLASS_CONTENT_SEC 0x0d /* content security */
	#define USB_CLASS_VIDEO 0x0e
	#define USB_CLASS_APP_SPEC 0xfe
	#define USB_CLASS_VENDOR_SPEC 0xff

	/-------------------------------------------------------------------------/

	/* USB_DT_CONFIG: Configuration descriptor information.
	*
	* USB_DT_OTHER_SPEED_CONFIG is the same descriptor, except that the
	* descriptor type is different. Highspeed-capable devices can look
	* different depending on what speed they're currently running. Only
	* devices with a USB_DT_DEVICE_QUALIFIER have any OTHER_SPEED_CONFIG
	* descriptors.
	*/
	struct usb_config_descriptor {
	__u8 bLength;
	__u8 bDescriptorType;

	__le16 wTotalLength;
	__u8 bNumInterfaces;
	__u8 bConfigurationValue;
	__u8 iConfiguration;
	__u8 bmAttributes;
	__u8 bMaxPower;
	} __attribute__ ((packed));

	#define USB_DT_CONFIG_SIZE 9

	/* from config descriptor bmAttributes */
	#define USB_CONFIG_ATT_ONE (1 << 7) /* must be set */
	#define USB_CONFIG_ATT_SELFPOWER (1 << 6) /* self powered */
	#define USB_CONFIG_ATT_WAKEUP (1 << 5) /* can wakeup */

	/-------------------------------------------------------------------------/

	/* USB_DT_STRING: String descriptor */
	struct usb_string_descriptor {
	__u8 bLength;
	__u8 bDescriptorType;

	__le16 wData[1]; /* UTF-16LE encoded */
	} __attribute__ ((packed));

	/* note that "string" zero is special, it holds language codes that
	* the device supports, not Unicode characters.
	*/

	/-------------------------------------------------------------------------/

	/* USB_DT_INTERFACE: Interface descriptor */
	struct usb_interface_descriptor {
	__u8 bLength;
	__u8 bDescriptorType;

	__u8 bInterfaceNumber;
	__u8 bAlternateSetting;
	__u8 bNumEndpoints;
	__u8 bInterfaceClass;
	__u8 bInterfaceSubClass;
	__u8 bInterfaceProtocol;
	__u8 iInterface;
	} __attribute__ ((packed));

	#define USB_DT_INTERFACE_SIZE 9

	/-------------------------------------------------------------------------/

	/* USB_DT_ENDPOINT: Endpoint descriptor */
	struct usb_endpoint_descriptor {
	__u8 bLength;
	__u8 bDescriptorType;

	__u8 bEndpointAddress;
	__u8 bmAttributes;
	__le16 wMaxPacketSize;
	__u8 bInterval;

	// NOTE: these two are _only_ in audio endpoints.
	// use USB_DT_ENDPOINT*_SIZE in bLength, not sizeof.
	__u8 bRefresh;
	__u8 bSynchAddress;
	} __attribute__ ((packed));

	#define USB_DT_ENDPOINT_SIZE 7
	#define USB_DT_ENDPOINT_AUDIO_SIZE 9 /* Audio extension */


	/*
	* Endpoints
	*/
	#define USB_ENDPOINT_NUMBER_MASK 0x0f /* in bEndpointAddress */
	#define USB_ENDPOINT_DIR_MASK 0x80

	#define USB_ENDPOINT_XFERTYPE_MASK 0x03 /* in bmAttributes */
	#define USB_ENDPOINT_XFER_CONTROL 0
	#define USB_ENDPOINT_XFER_ISOC 1
	#define USB_ENDPOINT_XFER_BULK 2
	#define USB_ENDPOINT_XFER_INT 3


	/-------------------------------------------------------------------------/

	/* USB_DT_DEVICE_QUALIFIER: Device Qualifier descriptor */
	struct usb_qualifier_descriptor {
	__u8 bLength;
	__u8 bDescriptorType;

	__le16 bcdUSB;
	__u8 bDeviceClass;
	__u8 bDeviceSubClass;
	__u8 bDeviceProtocol;
	__u8 bMaxPacketSize0;
	__u8 bNumConfigurations;
	__u8 bRESERVED;
	} __attribute__ ((packed));


	/-------------------------------------------------------------------------/

	/* USB_DT_OTG (from OTG 1.0a supplement) */
	struct usb_otg_descriptor {
	__u8 bLength;
	__u8 bDescriptorType;

	__u8 bmAttributes; /* support for HNP, SRP, etc */
	} __attribute__ ((packed));

	/* from usb_otg_descriptor.bmAttributes */
	#define USB_OTG_SRP (1 << 0)
	#define USB_OTG_HNP (1 << 1) /* swap host/device roles */

	/-------------------------------------------------------------------------/

	/* USB_DT_DEBUG: for special highspeed devices, replacing serial console */
	struct usb_debug_descriptor {
	__u8 bLength;
	__u8 bDescriptorType;

	/* bulk endpoints with 8 byte maxpacket */
	__u8 bDebugInEndpoint;
	__u8 bDebugOutEndpoint;
	};

	/-------------------------------------------------------------------------/

	/* USB_DT_INTERFACE_ASSOCIATION: groups interfaces */
	struct usb_interface_assoc_descriptor {
	__u8 bLength;
	__u8 bDescriptorType;

	__u8 bFirstInterface;
	__u8 bInterfaceCount;
	__u8 bFunctionClass;
	__u8 bFunctionSubClass;
	__u8 bFunctionProtocol;
	__u8 iFunction;
	} __attribute__ ((packed));


	/-------------------------------------------------------------------------/

	/* USB 2.0 defines three speeds, here's how Linux identifies them */

	enum usb_device_speed {
	USB_SPEED_UNKNOWN = 0, /* enumerating */
	USB_SPEED_LOW, USB_SPEED_FULL, /* usb 1.1 */
	USB_SPEED_HIGH /* usb 2.0 */
	};

	enum usb_device_state {
	/* NOTATTACHED isn't in the USB spec, and this state acts
	* the same as ATTACHED ... but it's clearer this way.
	*/
	USB_STATE_NOTATTACHED = 0,

	/* the chapter 9 device states */
	USB_STATE_ATTACHED,
	USB_STATE_POWERED,
	USB_STATE_DEFAULT, /* limited function */
	USB_STATE_ADDRESS,
	USB_STATE_CONFIGURED, /* most functions */

	USB_STATE_SUSPENDED

	/* NOTE: there are actually four different SUSPENDED
	* states, returning to POWERED, DEFAULT, ADDRESS, or
	* CONFIGURED respectively when SOF tokens flow again.
	*/
	};

	#endif /* __LINUX_USB_CH9_H */