Integrate USB gadget layer and USB CDC driver layer

Derived from Linux kernel 2.6.27

Signed-off-by: Thomas Smits <ts.smits@gmail.com>
Signed-off-by: Remy Bohmer <linux@bohmer.net>

3 files changed, 1682 insertions, 0 deletions

diff --git a/include/linux/usb/cdc.h b/include/linux/usb/cdc.h
new file mode 100644
index 00000000000..9b129c9ed24
--- /dev/null
+++ b/include/linux/usb/cdc.h
@@ -0,0 +1,224 @@
+/*
+ * USB Communications Device Class (CDC) definitions
+ *
+ * CDC says how to talk to lots of different types of network adapters,
+ * notably ethernet adapters and various modems.  It's used mostly with
+ * firmware based USB peripherals.
+ *
+ * Ported to U-boot by: Thomas Smits <ts.smits@gmail.com> and
+ *                      Remy Bohmer <linux@bohmer.net>
+ */
+
+
+
+#define USB_CDC_SUBCLASS_ACM			0x02
+#define USB_CDC_SUBCLASS_ETHERNET		0x06
+#define USB_CDC_SUBCLASS_WHCM			0x08
+#define USB_CDC_SUBCLASS_DMM			0x09
+#define USB_CDC_SUBCLASS_MDLM			0x0a
+#define USB_CDC_SUBCLASS_OBEX			0x0b
+
+#define USB_CDC_PROTO_NONE			0
+
+#define USB_CDC_ACM_PROTO_AT_V25TER		1
+#define USB_CDC_ACM_PROTO_AT_PCCA101		2
+#define USB_CDC_ACM_PROTO_AT_PCCA101_WAKE	3
+#define USB_CDC_ACM_PROTO_AT_GSM		4
+#define USB_CDC_ACM_PROTO_AT_3G			5
+#define USB_CDC_ACM_PROTO_AT_CDMA		6
+#define USB_CDC_ACM_PROTO_VENDOR		0xff
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Class-Specific descriptors ... there are a couple dozen of them
+ */
+
+#define USB_CDC_HEADER_TYPE		0x00		/* header_desc */
+#define USB_CDC_CALL_MANAGEMENT_TYPE	0x01		/* call_mgmt_descriptor */
+#define USB_CDC_ACM_TYPE		0x02		/* acm_descriptor */
+#define USB_CDC_UNION_TYPE		0x06		/* union_desc */
+#define USB_CDC_COUNTRY_TYPE		0x07
+#define USB_CDC_NETWORK_TERMINAL_TYPE	0x0a		/* network_terminal_desc */
+#define USB_CDC_ETHERNET_TYPE		0x0f		/* ether_desc */
+#define USB_CDC_WHCM_TYPE		0x11
+#define USB_CDC_MDLM_TYPE		0x12		/* mdlm_desc */
+#define USB_CDC_MDLM_DETAIL_TYPE	0x13		/* mdlm_detail_desc */
+#define USB_CDC_DMM_TYPE		0x14
+#define USB_CDC_OBEX_TYPE		0x15
+
+/* "Header Functional Descriptor" from CDC spec  5.2.3.1 */
+struct usb_cdc_header_desc {
+	__u8	bLength;
+	__u8	bDescriptorType;
+	__u8	bDescriptorSubType;
+
+	__le16	bcdCDC;
+} __attribute__ ((packed));
+
+/* "Call Management Descriptor" from CDC spec  5.2.3.2 */
+struct usb_cdc_call_mgmt_descriptor {
+	__u8	bLength;
+	__u8	bDescriptorType;
+	__u8	bDescriptorSubType;
+
+	__u8	bmCapabilities;
+#define USB_CDC_CALL_MGMT_CAP_CALL_MGMT		0x01
+#define USB_CDC_CALL_MGMT_CAP_DATA_INTF		0x02
+
+	__u8	bDataInterface;
+} __attribute__ ((packed));
+
+/* "Abstract Control Management Descriptor" from CDC spec  5.2.3.3 */
+struct usb_cdc_acm_descriptor {
+	__u8	bLength;
+	__u8	bDescriptorType;
+	__u8	bDescriptorSubType;
+
+	__u8	bmCapabilities;
+} __attribute__ ((packed));
+
+/* capabilities from 5.2.3.3 */
+
+#define USB_CDC_COMM_FEATURE	0x01
+#define USB_CDC_CAP_LINE	0x02
+#define USB_CDC_CAP_BRK	0x04
+#define USB_CDC_CAP_NOTIFY	0x08
+
+/* "Union Functional Descriptor" from CDC spec 5.2.3.8 */
+struct usb_cdc_union_desc {
+	__u8	bLength;
+	__u8	bDescriptorType;
+	__u8	bDescriptorSubType;
+
+	__u8	bMasterInterface0;
+	__u8	bSlaveInterface0;
+	/* ... and there could be other slave interfaces */
+} __attribute__ ((packed));
+
+/* "Country Selection Functional Descriptor" from CDC spec 5.2.3.9 */
+struct usb_cdc_country_functional_desc {
+	__u8	bLength;
+	__u8	bDescriptorType;
+	__u8	bDescriptorSubType;
+
+	__u8	iCountryCodeRelDate;
+	__le16	wCountyCode0;
+	/* ... and there can be a lot of country codes */
+} __attribute__ ((packed));
+
+/* "Network Channel Terminal Functional Descriptor" from CDC spec 5.2.3.11 */
+struct usb_cdc_network_terminal_desc {
+	__u8	bLength;
+	__u8	bDescriptorType;
+	__u8	bDescriptorSubType;
+
+	__u8	bEntityId;
+	__u8	iName;
+	__u8	bChannelIndex;
+	__u8	bPhysicalInterface;
+} __attribute__ ((packed));
+
+/* "Ethernet Networking Functional Descriptor" from CDC spec 5.2.3.16 */
+struct usb_cdc_ether_desc {
+	__u8	bLength;
+	__u8	bDescriptorType;
+	__u8	bDescriptorSubType;
+
+	__u8	iMACAddress;
+	__le32	bmEthernetStatistics;
+	__le16	wMaxSegmentSize;
+	__le16	wNumberMCFilters;
+	__u8	bNumberPowerFilters;
+} __attribute__ ((packed));
+
+/* "MDLM Functional Descriptor" from CDC WMC spec 6.7.2.3 */
+struct usb_cdc_mdlm_desc {
+	__u8	bLength;
+	__u8	bDescriptorType;
+	__u8	bDescriptorSubType;
+
+	__le16	bcdVersion;
+	__u8	bGUID[16];
+} __attribute__ ((packed));
+
+/* "MDLM Detail Functional Descriptor" from CDC WMC spec 6.7.2.4 */
+struct usb_cdc_mdlm_detail_desc {
+	__u8	bLength;
+	__u8	bDescriptorType;
+	__u8	bDescriptorSubType;
+
+	/* type is associated with mdlm_desc.bGUID */
+	__u8	bGuidDescriptorType;
+	__u8	bDetailData[0];
+} __attribute__ ((packed));
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Class-Specific Control Requests (6.2)
+ *
+ * section 3.6.2.1 table 4 has the ACM profile, for modems.
+ * section 3.8.2 table 10 has the ethernet profile.
+ */
+
+#define USB_CDC_SEND_ENCAPSULATED_COMMAND	0x00
+#define USB_CDC_GET_ENCAPSULATED_RESPONSE	0x01
+#define USB_CDC_REQ_SET_LINE_CODING		0x20
+#define USB_CDC_REQ_GET_LINE_CODING		0x21
+#define USB_CDC_REQ_SET_CONTROL_LINE_STATE	0x22
+#define USB_CDC_REQ_SEND_BREAK			0x23
+#define USB_CDC_SET_ETHERNET_MULTICAST_FILTERS	0x40
+#define USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER	0x41
+#define USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER	0x42
+#define USB_CDC_SET_ETHERNET_PACKET_FILTER	0x43
+#define USB_CDC_GET_ETHERNET_STATISTIC		0x44
+
+/* Line Coding Structure from CDC spec 6.2.13 */
+struct usb_cdc_line_coding {
+	__le32	dwDTERate;
+	__u8	bCharFormat;
+#define USB_CDC_1_STOP_BITS			0
+#define USB_CDC_1_5_STOP_BITS			1
+#define USB_CDC_2_STOP_BITS			2
+
+	__u8	bParityType;
+#define USB_CDC_NO_PARITY			0
+#define USB_CDC_ODD_PARITY			1
+#define USB_CDC_EVEN_PARITY			2
+#define USB_CDC_MARK_PARITY			3
+#define USB_CDC_SPACE_PARITY			4
+
+	__u8	bDataBits;
+} __attribute__ ((packed));
+
+/* table 62; bits in multicast filter */
+#define	USB_CDC_PACKET_TYPE_PROMISCUOUS		(1 << 0)
+#define	USB_CDC_PACKET_TYPE_ALL_MULTICAST	(1 << 1) /* no filter */
+#define	USB_CDC_PACKET_TYPE_DIRECTED		(1 << 2)
+#define	USB_CDC_PACKET_TYPE_BROADCAST		(1 << 3)
+#define	USB_CDC_PACKET_TYPE_MULTICAST		(1 << 4) /* filtered */
+
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Class-Specific Notifications (6.3) sent by interrupt transfers
+ *
+ * section 3.8.2 table 11 of the CDC spec lists Ethernet notifications
+ * section 3.6.2.1 table 5 specifies ACM notifications
+ */
+
+#define USB_CDC_NOTIFY_NETWORK_CONNECTION	0x00
+#define USB_CDC_NOTIFY_RESPONSE_AVAILABLE	0x01
+#define USB_CDC_NOTIFY_SERIAL_STATE		0x20
+#define USB_CDC_NOTIFY_SPEED_CHANGE		0x2a
+
+struct usb_cdc_notification {
+	__u8	bmRequestType;
+	__u8	bNotificationType;
+	__le16	wValue;
+	__le16	wIndex;
+	__le16	wLength;
+} __attribute__ ((packed));
+
diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h
new file mode 100644
index 00000000000..1091692e98e
--- /dev/null
+++ b/include/linux/usb/ch9.h
@@ -0,0 +1,587 @@
+/*
+ * 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 and in the
+ * Wireless USB 1.0 (spread around).  Linux has several APIs in C that
+ * need these:
+ *
+ * - the master/host side Linux-USB kernel driver API;
+ * - the "usbfs" user space API; and
+ * - the Linux "gadget" slave/device/peripheral 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 benefit from working well together.
+ *
+ * There's also "Wireless USB", using low power short range radios for
+ * peripheral interconnection but otherwise building on the USB framework.
+ *
+ * Note all descriptors are declared '__attribute__((packed))' so that:
+ *
+ * [a] they never get padded, either internally (USB spec writers
+ *     probably handled that) or externally;
+ *
+ * [b] so that accessing bigger-than-a-bytes fields will never
+ *     generate bus errors on any platform, even when the location of
+ *     its descriptor inside a bundle isn't "naturally aligned", and
+ *
+ * [c] for consistency, removing all doubt even when it appears to
+ *     someone that the two other points are non-issues for that
+ *     particular descriptor type.
+ *
+ * Ported to U-boot by: Thomas Smits <ts.smits@gmail.com> and
+ *                      Remy Bohmer <linux@bohmer.net>
+ */
+
+#ifndef __LINUX_USB_CH9_H
+#define __LINUX_USB_CH9_H
+
+#include <linux/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
+/* From Wireless USB 1.0 */
+#define USB_RECIP_PORT 			0x04
+#define USB_RECIP_RPIPE 		0x05
+
+/*
+ * 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
+
+#define USB_REQ_SET_ENCRYPTION		0x0D	/* Wireless USB */
+#define USB_REQ_GET_ENCRYPTION		0x0E
+#define USB_REQ_RPIPE_ABORT		0x0E
+#define USB_REQ_SET_HANDSHAKE		0x0F
+#define USB_REQ_RPIPE_RESET		0x0F
+#define USB_REQ_GET_HANDSHAKE		0x10
+#define USB_REQ_SET_CONNECTION		0x11
+#define USB_REQ_SET_SECURITY_DATA	0x12
+#define USB_REQ_GET_SECURITY_DATA	0x13
+#define USB_REQ_SET_WUSB_DATA		0x14
+#define USB_REQ_LOOPBACK_DATA_WRITE	0x15
+#define USB_REQ_LOOPBACK_DATA_READ	0x16
+#define USB_REQ_SET_INTERFACE_DS	0x17
+
+/*
+ * 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	/* (wired high speed only) */
+#define USB_DEVICE_BATTERY		2	/* (wireless) */
+#define USB_DEVICE_B_HNP_ENABLE		3	/* (otg) dev may initiate HNP */
+#define USB_DEVICE_WUSB_DEVICE		3	/* (wireless)*/
+#define USB_DEVICE_A_HNP_SUPPORT	4	/* (otg) RH port supports HNP */
+#define USB_DEVICE_A_ALT_HNP_SUPPORT	5	/* (otg) 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.
+ */
+#if defined(__BIG_ENDIAN) || defined(__ARMEB__)
+#error (functionality not verified for big endian targets, todo...)
+#endif
+
+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
+/* these are from the Wireless USB spec */
+#define USB_DT_SECURITY			0x0c
+#define USB_DT_KEY			0x0d
+#define USB_DT_ENCRYPTION_TYPE		0x0e
+#define USB_DT_BOS			0x0f
+#define USB_DT_DEVICE_CAPABILITY	0x10
+#define USB_DT_WIRELESS_ENDPOINT_COMP	0x11
+#define USB_DT_WIRE_ADAPTER		0x21
+#define USB_DT_RPIPE			0x22
+
+/* Conventional codes for class-specific descriptors.  The convention is
+ * defined in the USB "Common Class" Spec (3.11).  Individual class specs
+ * are authoritative for their usage, not the "common class" writeup.
+ */
+#define USB_DT_CS_DEVICE		(USB_TYPE_CLASS | USB_DT_DEVICE)
+#define USB_DT_CS_CONFIG		(USB_TYPE_CLASS | USB_DT_CONFIG)
+#define USB_DT_CS_STRING		(USB_TYPE_CLASS | USB_DT_STRING)
+#define USB_DT_CS_INTERFACE		(USB_TYPE_CLASS | USB_DT_INTERFACE)
+#define USB_DT_CS_ENDPOINT		(USB_TYPE_CLASS | USB_DT_ENDPOINT)
+
+/* 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_WIRELESS_CONTROLLER	0xe0
+#define USB_CLASS_MISC			0xef
+#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 */
+#define USB_CONFIG_ATT_BATTERY		(1 << 4)	/* battery powered */
+
+/*-------------------------------------------------------------------------*/
+
+/* 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
+#define USB_ENDPOINT_MAX_ADJUSTABLE	0x80
+
+
+/*-------------------------------------------------------------------------*/
+
+/* 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;
+} __attribute__((packed));
+
+/*-------------------------------------------------------------------------*/
+
+/* 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_DT_SECURITY:  group of wireless security descriptors, including
+ * encryption types available for setting up a CC/association.
+ */
+struct usb_security_descriptor {
+	__u8  bLength;
+	__u8  bDescriptorType;
+
+	__le16 wTotalLength;
+	__u8  bNumEncryptionTypes;
+} __attribute__((packed));
+
+/*-------------------------------------------------------------------------*/
+
+/* USB_DT_KEY:  used with {GET,SET}_SECURITY_DATA; only public keys
+ * may be retrieved.
+ */
+struct usb_key_descriptor {
+	__u8  bLength;
+	__u8  bDescriptorType;
+
+	__u8  tTKID[3];
+	__u8  bReserved;
+	__u8  bKeyData[0];
+} __attribute__((packed));
+
+/*-------------------------------------------------------------------------*/
+
+/* USB_DT_ENCRYPTION_TYPE:  bundled in DT_SECURITY groups */
+struct usb_encryption_descriptor {
+	__u8  bLength;
+	__u8  bDescriptorType;
+
+	__u8  bEncryptionType;
+#define	USB_ENC_TYPE_UNSECURE		0
+#define	USB_ENC_TYPE_WIRED		1	/* non-wireless mode */
+#define	USB_ENC_TYPE_CCM_1		2	/* aes128/cbc session */
+#define	USB_ENC_TYPE_RSA_1		3	/* rsa3072/sha1 auth */
+	__u8  bEncryptionValue;		/* use in SET_ENCRYPTION */
+	__u8  bAuthKeyIndex;
+} __attribute__((packed));
+
+
+/*-------------------------------------------------------------------------*/
+
+/* USB_DT_BOS:  group of wireless capabilities */
+struct usb_bos_descriptor {
+	__u8  bLength;
+	__u8  bDescriptorType;
+
+	__le16 wTotalLength;
+	__u8  bNumDeviceCaps;
+} __attribute__((packed));
+
+/*-------------------------------------------------------------------------*/
+
+/* USB_DT_DEVICE_CAPABILITY:  grouped with BOS */
+struct usb_dev_cap_header {
+	__u8  bLength;
+	__u8  bDescriptorType;
+	__u8  bDevCapabilityType;
+} __attribute__((packed));
+
+#define	USB_CAP_TYPE_WIRELESS_USB	1
+
+struct usb_wireless_cap_descriptor {	/* Ultra Wide Band */
+	__u8  bLength;
+	__u8  bDescriptorType;
+	__u8  bDevCapabilityType;
+
+	__u8  bmAttributes;
+#define	USB_WIRELESS_P2P_DRD		(1 << 1)
+#define	USB_WIRELESS_BEACON_MASK	(3 << 2)
+#define	USB_WIRELESS_BEACON_SELF	(1 << 2)
+#define	USB_WIRELESS_BEACON_DIRECTED	(2 << 2)
+#define	USB_WIRELESS_BEACON_NONE	(3 << 2)
+	__le16 wPHYRates;	/* bit rates, Mbps */
+#define	USB_WIRELESS_PHY_53		(1 << 0)	/* always set */
+#define	USB_WIRELESS_PHY_80		(1 << 1)
+#define	USB_WIRELESS_PHY_107		(1 << 2)	/* always set */
+#define	USB_WIRELESS_PHY_160		(1 << 3)
+#define	USB_WIRELESS_PHY_200		(1 << 4)	/* always set */
+#define	USB_WIRELESS_PHY_320		(1 << 5)
+#define	USB_WIRELESS_PHY_400		(1 << 6)
+#define	USB_WIRELESS_PHY_480		(1 << 7)
+	__u8  bmTFITXPowerInfo;	/* TFI power levels */
+	__u8  bmFFITXPowerInfo;	/* FFI power levels */
+	__le16 bmBandGroup;
+	__u8  bReserved;
+} __attribute__((packed));
+
+/*-------------------------------------------------------------------------*/
+
+/* USB_DT_WIRELESS_ENDPOINT_COMP:  companion descriptor associated with
+ * each endpoint descriptor for a wireless device
+ */
+struct usb_wireless_ep_comp_descriptor {
+	__u8  bLength;
+	__u8  bDescriptorType;
+
+	__u8  bMaxBurst;
+	__u8  bMaxSequence;
+	__le16 wMaxStreamDelay;
+	__le16 wOverTheAirPacketSize;
+	__u8  bOverTheAirInterval;
+	__u8  bmCompAttributes;
+#define USB_ENDPOINT_SWITCH_MASK	0x03	/* in bmCompAttributes */
+#define USB_ENDPOINT_SWITCH_NO		0
+#define USB_ENDPOINT_SWITCH_SWITCH	1
+#define USB_ENDPOINT_SWITCH_SCALE	2
+} __attribute__((packed));
+
+/*-------------------------------------------------------------------------*/
+
+/* USB_REQ_SET_HANDSHAKE is a four-way handshake used between a wireless
+ * host and a device for connection set up, mutual authentication, and
+ * exchanging short lived session keys.  The handshake depends on a CC.
+ */
+struct usb_handshake {
+	__u8 bMessageNumber;
+	__u8 bStatus;
+	__u8 tTKID[3];
+	__u8 bReserved;
+	__u8 CDID[16];
+	__u8 nonce[16];
+	__u8 MIC[8];
+} __attribute__((packed));
+
+/*-------------------------------------------------------------------------*/
+
+/* USB_REQ_SET_CONNECTION modifies or revokes a connection context (CC).
+ * A CC may also be set up using non-wireless secure channels (including
+ * wired USB!), and some devices may support CCs with multiple hosts.
+ */
+struct usb_connection_context {
+	__u8 CHID[16];		/* persistent host id */
+	__u8 CDID[16];		/* device id (unique w/in host context) */
+	__u8 CK[16];		/* connection key */
+} __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 */
+	USB_SPEED_VARIABLE,			/* wireless (usb 2.5) */
+};
+
+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,
+
+	/* chapter 9 and authentication (wireless) device states */
+	USB_STATE_ATTACHED,
+	USB_STATE_POWERED,			/* wired */
+	USB_STATE_UNAUTHENTICATED,		/* auth */
+	USB_STATE_RECONNECTING,			/* auth */
+	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 */
diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
new file mode 100644
index 00000000000..344fc787c05
--- /dev/null
+++ b/include/linux/usb/gadget.h
@@ -0,0 +1,871 @@
+/*
+ * <linux/usb/gadget.h>
+ *
+ * We call the USB code inside a Linux-based peripheral device a "gadget"
+ * driver, except for the hardware-specific bus glue.  One USB host can
+ * master many USB gadgets, but the gadgets are only slaved to one host.
+ *
+ *
+ * (C) Copyright 2002-2004 by David Brownell
+ * All Rights Reserved.
+ *
+ * This software is licensed under the GNU GPL version 2.
+ *
+ * Ported to U-boot by: Thomas Smits <ts.smits@gmail.com> and
+ *                      Remy Bohmer <linux@bohmer.net>
+ */
+
+#ifndef __LINUX_USB_GADGET_H
+#define __LINUX_USB_GADGET_H
+
+#include <linux/list.h>
+
+struct usb_ep;
+
+/**
+ * struct usb_request - describes one i/o request
+ * @buf: Buffer used for data.  Always provide this; some controllers
+ *	only use PIO, or don't use DMA for some endpoints.
+ * @dma: DMA address corresponding to 'buf'.  If you don't set this
+ *	field, and the usb controller needs one, it is responsible
+ *	for mapping and unmapping the buffer.
+ * @length: Length of that data
+ * @no_interrupt: If true, hints that no completion irq is needed.
+ *	Helpful sometimes with deep request queues that are handled
+ *	directly by DMA controllers.
+ * @zero: If true, when writing data, makes the last packet be "short"
+ *     by adding a zero length packet as needed;
+ * @short_not_ok: When reading data, makes short packets be
+ *     treated as errors (queue stops advancing till cleanup).
+ * @complete: Function called when request completes, so this request and
+ *	its buffer may be re-used.
+ *	Reads terminate with a short packet, or when the buffer fills,
+ *	whichever comes first.  When writes terminate, some data bytes
+ *	will usually still be in flight (often in a hardware fifo).
+ *	Errors (for reads or writes) stop the queue from advancing
+ *	until the completion function returns, so that any transfers
+ *	invalidated by the error may first be dequeued.
+ * @context: For use by the completion callback
+ * @list: For use by the gadget driver.
+ * @status: Reports completion code, zero or a negative errno.
+ *	Normally, faults block the transfer queue from advancing until
+ *	the completion callback returns.
+ *	Code "-ESHUTDOWN" indicates completion caused by device disconnect,
+ *	or when the driver disabled the endpoint.
+ * @actual: Reports bytes transferred to/from the buffer.  For reads (OUT
+ *	transfers) this may be less than the requested length.  If the
+ *	short_not_ok flag is set, short reads are treated as errors
+ *	even when status otherwise indicates successful completion.
+ *	Note that for writes (IN transfers) some data bytes may still
+ *	reside in a device-side FIFO when the request is reported as
+ *	complete.
+ *
+ * These are allocated/freed through the endpoint they're used with.  The
+ * hardware's driver can add extra per-request data to the memory it returns,
+ * which often avoids separate memory allocations (potential failures),
+ * later when the request is queued.
+ *
+ * Request flags affect request handling, such as whether a zero length
+ * packet is written (the "zero" flag), whether a short read should be
+ * treated as an error (blocking request queue advance, the "short_not_ok"
+ * flag), or hinting that an interrupt is not required (the "no_interrupt"
+ * flag, for use with deep request queues).
+ *
+ * Bulk endpoints can use any size buffers, and can also be used for interrupt
+ * transfers. interrupt-only endpoints can be much less functional.
+ */
+	// NOTE this is analagous to 'struct urb' on the host side,
+	// except that it's thinner and promotes more pre-allocation.
+
+struct usb_request {
+	void			*buf;
+	unsigned		length;
+	dma_addr_t		dma;
+
+	unsigned		no_interrupt:1;
+	unsigned		zero:1;
+	unsigned		short_not_ok:1;
+
+	void			(*complete)(struct usb_ep *ep,
+					struct usb_request *req);
+	void			*context;
+	struct list_head	list;
+
+	int			status;
+	unsigned		actual;
+};
+
+/*-------------------------------------------------------------------------*/
+
+/* endpoint-specific parts of the api to the usb controller hardware.
+ * unlike the urb model, (de)multiplexing layers are not required.
+ * (so this api could slash overhead if used on the host side...)
+ *
+ * note that device side usb controllers commonly differ in how many
+ * endpoints they support, as well as their capabilities.
+ */
+struct usb_ep_ops {
+	int (*enable) (struct usb_ep *ep,
+		const struct usb_endpoint_descriptor *desc);
+	int (*disable) (struct usb_ep *ep);
+
+	struct usb_request *(*alloc_request) (struct usb_ep *ep,
+		gfp_t gfp_flags);
+	void (*free_request) (struct usb_ep *ep, struct usb_request *req);
+
+	int (*queue) (struct usb_ep *ep, struct usb_request *req,
+		gfp_t gfp_flags);
+	int (*dequeue) (struct usb_ep *ep, struct usb_request *req);
+
+	int (*set_halt) (struct usb_ep *ep, int value);
+	int (*fifo_status) (struct usb_ep *ep);
+	void (*fifo_flush) (struct usb_ep *ep);
+};
+
+/**
+ * struct usb_ep - device side representation of USB endpoint
+ * @name:identifier for the endpoint, such as "ep-a" or "ep9in-bulk"
+ * @ops: Function pointers used to access hardware-specific operations.
+ * @ep_list:the gadget's ep_list holds all of its endpoints
+ * @maxpacket:The maximum packet size used on this endpoint.  The initial
+ *	value can sometimes be reduced (hardware allowing), according to
+ *      the endpoint descriptor used to configure the endpoint.
+ * @driver_data:for use by the gadget driver.  all other fields are
+ *	read-only to gadget drivers.
+ *
+ * the bus controller driver lists all the general purpose endpoints in
+ * gadget->ep_list.  the control endpoint (gadget->ep0) is not in that list,
+ * and is accessed only in response to a driver setup() callback.
+ */
+struct usb_ep {
+	void			*driver_data;
+	const char		*name;
+	const struct usb_ep_ops	*ops;
+	struct list_head	ep_list;
+	unsigned		maxpacket:16;
+};
+
+/*-------------------------------------------------------------------------*/
+
+/**
+ * usb_ep_enable - configure endpoint, making it usable
+ * @ep:the endpoint being configured.  may not be the endpoint named "ep0".
+ *	drivers discover endpoints through the ep_list of a usb_gadget.
+ * @desc:descriptor for desired behavior.  caller guarantees this pointer
+ *	remains valid until the endpoint is disabled; the data byte order
+ *	is little-endian (usb-standard).
+ *
+ * when configurations are set, or when interface settings change, the driver
+ * will enable or disable the relevant endpoints.  while it is enabled, an
+ * endpoint may be used for i/o until the driver receives a disconnect() from
+ * the host or until the endpoint is disabled.
+ *
+ * the ep0 implementation (which calls this routine) must ensure that the
+ * hardware capabilities of each endpoint match the descriptor provided
+ * for it.  for example, an endpoint named "ep2in-bulk" would be usable
+ * for interrupt transfers as well as bulk, but it likely couldn't be used
+ * for iso transfers or for endpoint 14.  some endpoints are fully
+ * configurable, with more generic names like "ep-a".  (remember that for
+ * USB, "in" means "towards the USB master".)
+ *
+ * returns zero, or a negative error code.
+ */
+static inline int
+usb_ep_enable (struct usb_ep *ep, const struct usb_endpoint_descriptor *desc)
+{
+	return ep->ops->enable (ep, desc);
+}
+
+/**
+ * usb_ep_disable - endpoint is no longer usable
+ * @ep:the endpoint being unconfigured.  may not be the endpoint named "ep0".
+ *
+ * no other task may be using this endpoint when this is called.
+ * any pending and uncompleted requests will complete with status
+ * indicating disconnect (-ESHUTDOWN) before this call returns.
+ * gadget drivers must call usb_ep_enable() again before queueing
+ * requests to the endpoint.
+ *
+ * returns zero, or a negative error code.
+ */
+static inline int
+usb_ep_disable (struct usb_ep *ep)
+{
+	return ep->ops->disable (ep);
+}
+
+/**
+ * usb_ep_alloc_request - allocate a request object to use with this endpoint
+ * @ep:the endpoint to be used with with the request
+ * @gfp_flags:GFP_* flags to use
+ *
+ * Request objects must be allocated with this call, since they normally
+ * need controller-specific setup and may even need endpoint-specific
+ * resources such as allocation of DMA descriptors.
+ * Requests may be submitted with usb_ep_queue(), and receive a single
+ * completion callback.  Free requests with usb_ep_free_request(), when
+ * they are no longer needed.
+ *
+ * Returns the request, or null if one could not be allocated.
+ */
+static inline struct usb_request *
+usb_ep_alloc_request (struct usb_ep *ep, gfp_t gfp_flags)
+{
+	return ep->ops->alloc_request (ep, gfp_flags);
+}
+
+/**
+ * usb_ep_free_request - frees a request object
+ * @ep:the endpoint associated with the request
+ * @req:the request being freed
+ *
+ * Reverses the effect of usb_ep_alloc_request().
+ * Caller guarantees the request is not queued, and that it will
+ * no longer be requeued (or otherwise used).
+ */
+static inline void
+usb_ep_free_request (struct usb_ep *ep, struct usb_request *req)
+{
+	ep->ops->free_request (ep, req);
+}
+
+/**
+ * usb_ep_queue - queues (submits) an I/O request to an endpoint.
+ * @ep:the endpoint associated with the request
+ * @req:the request being submitted
+ * @gfp_flags: GFP_* flags to use in case the lower level driver couldn't
+ *	pre-allocate all necessary memory with the request.
+ *
+ * This tells the device controller to perform the specified request through
+ * that endpoint (reading or writing a buffer).  When the request completes,
+ * including being canceled by usb_ep_dequeue(), the request's completion
+ * routine is called to return the request to the driver.  Any endpoint
+ * (except control endpoints like ep0) may have more than one transfer
+ * request queued; they complete in FIFO order.  Once a gadget driver
+ * submits a request, that request may not be examined or modified until it
+ * is given back to that driver through the completion callback.
+ *
+ * Each request is turned into one or more packets.  The controller driver
+ * never merges adjacent requests into the same packet.  OUT transfers
+ * will sometimes use data that's already buffered in the hardware.
+ * Drivers can rely on the fact that the first byte of the request's buffer
+ * always corresponds to the first byte of some USB packet, for both
+ * IN and OUT transfers.
+ *
+ * Bulk endpoints can queue any amount of data; the transfer is packetized
+ * automatically.  The last packet will be short if the request doesn't fill it
+ * out completely.  Zero length packets (ZLPs) should be avoided in portable
+ * protocols since not all usb hardware can successfully handle zero length
+ * packets.  (ZLPs may be explicitly written, and may be implicitly written if
+ * the request 'zero' flag is set.)  Bulk endpoints may also be used
+ * for interrupt transfers; but the reverse is not true, and some endpoints
+ * won't support every interrupt transfer.  (Such as 768 byte packets.)
+ *
+ * Interrupt-only endpoints are less functional than bulk endpoints, for
+ * example by not supporting queueing or not handling buffers that are
+ * larger than the endpoint's maxpacket size.  They may also treat data
+ * toggle differently.
+ *
+ * Control endpoints ... after getting a setup() callback, the driver queues
+ * one response (even if it would be zero length).  That enables the
+ * status ack, after transfering data as specified in the response.  Setup
+ * functions may return negative error codes to generate protocol stalls.
+ * (Note that some USB device controllers disallow protocol stall responses
+ * in some cases.)  When control responses are deferred (the response is
+ * written after the setup callback returns), then usb_ep_set_halt() may be
+ * used on ep0 to trigger protocol stalls.
+ *
+ * For periodic endpoints, like interrupt or isochronous ones, the usb host
+ * arranges to poll once per interval, and the gadget driver usually will
+ * have queued some data to transfer at that time.
+ *
+ * Returns zero, or a negative error code.  Endpoints that are not enabled
+ * report errors; errors will also be
+ * reported when the usb peripheral is disconnected.
+ */
+static inline int
+usb_ep_queue (struct usb_ep *ep, struct usb_request *req, gfp_t gfp_flags)
+{
+	return ep->ops->queue (ep, req, gfp_flags);
+}
+
+/**
+ * usb_ep_dequeue - dequeues (cancels, unlinks) an I/O request from an endpoint
+ * @ep:the endpoint associated with the request
+ * @req:the request being canceled
+ *
+ * if the request is still active on the endpoint, it is dequeued and its
+ * completion routine is called (with status -ECONNRESET); else a negative
+ * error code is returned.
+ *
+ * note that some hardware can't clear out write fifos (to unlink the request
+ * at the head of the queue) except as part of disconnecting from usb.  such
+ * restrictions prevent drivers from supporting configuration changes,
+ * even to configuration zero (a "chapter 9" requirement).
+ */
+static inline int usb_ep_dequeue (struct usb_ep *ep, struct usb_request *req)
+{
+	return ep->ops->dequeue (ep, req);
+}
+
+/**
+ * usb_ep_set_halt - sets the endpoint halt feature.
+ * @ep: the non-isochronous endpoint being stalled
+ *
+ * Use this to stall an endpoint, perhaps as an error report.
+ * Except for control endpoints,
+ * the endpoint stays halted (will not stream any data) until the host
+ * clears this feature; drivers may need to empty the endpoint's request
+ * queue first, to make sure no inappropriate transfers happen.
+ *
+ * Note that while an endpoint CLEAR_FEATURE will be invisible to the
+ * gadget driver, a SET_INTERFACE will not be.  To reset endpoints for the
+ * current altsetting, see usb_ep_clear_halt().  When switching altsettings,
+ * it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints.
+ *
+ * Returns zero, or a negative error code.  On success, this call sets
+ * underlying hardware state that blocks data transfers.
+ * Attempts to halt IN endpoints will fail (returning -EAGAIN) if any
+ * transfer requests are still queued, or if the controller hardware
+ * (usually a FIFO) still holds bytes that the host hasn't collected.
+ */
+static inline int
+usb_ep_set_halt (struct usb_ep *ep)
+{
+	return ep->ops->set_halt (ep, 1);
+}
+
+/**
+ * usb_ep_clear_halt - clears endpoint halt, and resets toggle
+ * @ep:the bulk or interrupt endpoint being reset
+ *
+ * Use this when responding to the standard usb "set interface" request,
+ * for endpoints that aren't reconfigured, after clearing any other state
+ * in the endpoint's i/o queue.
+ *
+ * Returns zero, or a negative error code.  On success, this call clears
+ * the underlying hardware state reflecting endpoint halt and data toggle.
+ * Note that some hardware can't support this request (like pxa2xx_udc),
+ * and accordingly can't correctly implement interface altsettings.
+ */
+static inline int
+usb_ep_clear_halt (struct usb_ep *ep)
+{
+	return ep->ops->set_halt (ep, 0);
+}
+
+/**
+ * usb_ep_fifo_status - returns number of bytes in fifo, or error
+ * @ep: the endpoint whose fifo status is being checked.
+ *
+ * FIFO endpoints may have "unclaimed data" in them in certain cases,
+ * such as after aborted transfers.  Hosts may not have collected all
+ * the IN data written by the gadget driver (and reported by a request
+ * completion).  The gadget driver may not have collected all the data
+ * written OUT to it by the host.  Drivers that need precise handling for
+ * fault reporting or recovery may need to use this call.
+ *
+ * This returns the number of such bytes in the fifo, or a negative
+ * errno if the endpoint doesn't use a FIFO or doesn't support such
+ * precise handling.
+ */
+static inline int
+usb_ep_fifo_status (struct usb_ep *ep)
+{
+	if (ep->ops->fifo_status)
+		return ep->ops->fifo_status (ep);
+	else
+		return -EOPNOTSUPP;
+}
+
+/**
+ * usb_ep_fifo_flush - flushes contents of a fifo
+ * @ep: the endpoint whose fifo is being flushed.
+ *
+ * This call may be used to flush the "unclaimed data" that may exist in
+ * an endpoint fifo after abnormal transaction terminations.  The call
+ * must never be used except when endpoint is not being used for any
+ * protocol translation.
+ */
+static inline void
+usb_ep_fifo_flush (struct usb_ep *ep)
+{
+	if (ep->ops->fifo_flush)
+		ep->ops->fifo_flush (ep);
+}
+
+
+/*-------------------------------------------------------------------------*/
+
+struct usb_gadget;
+
+/* the rest of the api to the controller hardware: device operations,
+ * which don't involve endpoints (or i/o).
+ */
+struct usb_gadget_ops {
+	int	(*get_frame)(struct usb_gadget *);
+	int	(*wakeup)(struct usb_gadget *);
+	int	(*set_selfpowered) (struct usb_gadget *, int is_selfpowered);
+	int	(*vbus_session) (struct usb_gadget *, int is_active);
+	int	(*vbus_draw) (struct usb_gadget *, unsigned mA);
+	int	(*pullup) (struct usb_gadget *, int is_on);
+	int	(*ioctl)(struct usb_gadget *,
+				unsigned code, unsigned long param);
+};
+
+struct device {
+	void		*driver_data;	/* data private to the driver */
+};
+
+/**
+ * struct usb_gadget - represents a usb slave device
+ * @ops: Function pointers used to access hardware-specific operations.
+ * @ep0: Endpoint zero, used when reading or writing responses to
+ *	driver setup() requests
+ * @ep_list: List of other endpoints supported by the device.
+ * @speed: Speed of current connection to USB host.
+ * @is_dualspeed: True if the controller supports both high and full speed
+ *	operation.  If it does, the gadget driver must also support both.
+ * @is_otg: True if the USB device port uses a Mini-AB jack, so that the
+ *	gadget driver must provide a USB OTG descriptor.
+ * @is_a_peripheral: False unless is_otg, the "A" end of a USB cable
+ *	is in the Mini-AB jack, and HNP has been used to switch roles
+ *	so that the "A" device currently acts as A-Peripheral, not A-Host.
+ * @a_hnp_support: OTG device feature flag, indicating that the A-Host
+ *	supports HNP at this port.
+ * @a_alt_hnp_support: OTG device feature flag, indicating that the A-Host
+ *	only supports HNP on a different root port.
+ * @b_hnp_enable: OTG device feature flag, indicating that the A-Host
+ *	enabled HNP support.
+ * @name: Identifies the controller hardware type.  Used in diagnostics
+ *	and sometimes configuration.
+ * @dev: Driver model state for this abstract device.
+ *
+ * Gadgets have a mostly-portable "gadget driver" implementing device
+ * functions, handling all usb configurations and interfaces.  Gadget
+ * drivers talk to hardware-specific code indirectly, through ops vectors.
+ * That insulates the gadget driver from hardware details, and packages
+ * the hardware endpoints through generic i/o queues.  The "usb_gadget"
+ * and "usb_ep" interfaces provide that insulation from the hardware.
+ *
+ * Except for the driver data, all fields in this structure are
+ * read-only to the gadget driver.  That driver data is part of the
+ * "driver model" infrastructure in 2.6 (and later) kernels, and for
+ * earlier systems is grouped in a similar structure that's not known
+ * to the rest of the kernel.
+ *
+ * Values of the three OTG device feature flags are updated before the
+ * setup() call corresponding to USB_REQ_SET_CONFIGURATION, and before
+ * driver suspend() calls.  They are valid only when is_otg, and when the
+ * device is acting as a B-Peripheral (so is_a_peripheral is false).
+ */
+struct usb_gadget {
+	/* readonly to gadget driver */
+	const struct usb_gadget_ops	*ops;
+	struct usb_ep			*ep0;
+	struct list_head		ep_list;	/* of usb_ep */
+	enum usb_device_speed		speed;
+	unsigned			is_dualspeed:1;
+	unsigned			is_otg:1;
+	unsigned			is_a_peripheral:1;
+	unsigned			b_hnp_enable:1;
+	unsigned			a_hnp_support:1;
+	unsigned			a_alt_hnp_support:1;
+	const char			*name;
+	struct device			dev;
+};
+
+static inline void set_gadget_data (struct usb_gadget *gadget, void *data)
+{
+	gadget->dev.driver_data = data;
+}
+
+static inline void *get_gadget_data (struct usb_gadget *gadget)
+{
+	return gadget->dev.driver_data;
+}
+
+/* iterates the non-control endpoints; 'tmp' is a struct usb_ep pointer */
+#define gadget_for_each_ep(tmp,gadget) \
+	list_for_each_entry(tmp, &(gadget)->ep_list, ep_list)
+
+
+/**
+ * gadget_is_dualspeed - return true iff the hardware handles high speed
+ * @g: controller that might support both high and full speeds
+ */
+static inline int gadget_is_dualspeed(struct usb_gadget *g)
+{
+#ifdef CONFIG_USB_GADGET_DUALSPEED
+	/* runtime test would check "g->is_dualspeed" ... that might be
+	 * useful to work around hardware bugs, but is mostly pointless
+	 */
+	return 1;
+#else
+	return 0;
+#endif
+}
+
+/**
+ * gadget_is_otg - return true iff the hardware is OTG-ready
+ * @g: controller that might have a Mini-AB connector
+ *
+ * This is a runtime test, since kernels with a USB-OTG stack sometimes
+ * run on boards which only have a Mini-B (or Mini-A) connector.
+ */
+static inline int gadget_is_otg(struct usb_gadget *g)
+{
+#ifdef CONFIG_USB_OTG
+	return g->is_otg;
+#else
+	return 0;
+#endif
+}
+
+
+/**
+ * usb_gadget_frame_number - returns the current frame number
+ * @gadget: controller that reports the frame number
+ *
+ * Returns the usb frame number, normally eleven bits from a SOF packet,
+ * or negative errno if this device doesn't support this capability.
+ */
+static inline int usb_gadget_frame_number (struct usb_gadget *gadget)
+{
+	return gadget->ops->get_frame (gadget);
+}
+
+/**
+ * usb_gadget_wakeup - tries to wake up the host connected to this gadget
+ * @gadget: controller used to wake up the host
+ *
+ * Returns zero on success, else negative error code if the hardware
+ * doesn't support such attempts, or its support has not been enabled
+ * by the usb host.  Drivers must return device descriptors that report
+ * their ability to support this, or hosts won't enable it.
+ *
+ * This may also try to use SRP to wake the host and start enumeration,
+ * even if OTG isn't otherwise in use.  OTG devices may also start
+ * remote wakeup even when hosts don't explicitly enable it.
+ */
+static inline int usb_gadget_wakeup (struct usb_gadget *gadget)
+{
+	if (!gadget->ops->wakeup)
+		return -EOPNOTSUPP;
+	return gadget->ops->wakeup (gadget);
+}
+
+/**
+ * usb_gadget_set_selfpowered - sets the device selfpowered feature.
+ * @gadget:the device being declared as self-powered
+ *
+ * this affects the device status reported by the hardware driver
+ * to reflect that it now has a local power supply.
+ *
+ * returns zero on success, else negative errno.
+ */
+static inline int
+usb_gadget_set_selfpowered (struct usb_gadget *gadget)
+{
+	if (!gadget->ops->set_selfpowered)
+		return -EOPNOTSUPP;
+	return gadget->ops->set_selfpowered (gadget, 1);
+}
+
+/**
+ * usb_gadget_clear_selfpowered - clear the device selfpowered feature.
+ * @gadget:the device being declared as bus-powered
+ *
+ * this affects the device status reported by the hardware driver.
+ * some hardware may not support bus-powered operation, in which
+ * case this feature's value can never change.
+ *
+ * returns zero on success, else negative errno.
+ */
+static inline int
+usb_gadget_clear_selfpowered (struct usb_gadget *gadget)
+{
+	if (!gadget->ops->set_selfpowered)
+		return -EOPNOTSUPP;
+	return gadget->ops->set_selfpowered (gadget, 0);
+}
+
+/**
+ * usb_gadget_vbus_connect - Notify controller that VBUS is powered
+ * @gadget:The device which now has VBUS power.
+ *
+ * This call is used by a driver for an external transceiver (or GPIO)
+ * that detects a VBUS power session starting.  Common responses include
+ * resuming the controller, activating the D+ (or D-) pullup to let the
+ * host detect that a USB device is attached, and starting to draw power
+ * (8mA or possibly more, especially after SET_CONFIGURATION).
+ *
+ * Returns zero on success, else negative errno.
+ */
+static inline int
+usb_gadget_vbus_connect(struct usb_gadget *gadget)
+{
+	if (!gadget->ops->vbus_session)
+		return -EOPNOTSUPP;
+	return gadget->ops->vbus_session (gadget, 1);
+}
+
+/**
+ * usb_gadget_vbus_draw - constrain controller's VBUS power usage
+ * @gadget:The device whose VBUS usage is being described
+ * @mA:How much current to draw, in milliAmperes.  This should be twice
+ *	the value listed in the configuration descriptor bMaxPower field.
+ *
+ * This call is used by gadget drivers during SET_CONFIGURATION calls,
+ * reporting how much power the device may consume.  For example, this
+ * could affect how quickly batteries are recharged.
+ *
+ * Returns zero on success, else negative errno.
+ */
+static inline int
+usb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
+{
+	if (!gadget->ops->vbus_draw)
+		return -EOPNOTSUPP;
+	return gadget->ops->vbus_draw (gadget, mA);
+}
+
+/**
+ * usb_gadget_vbus_disconnect - notify controller about VBUS session end
+ * @gadget:the device whose VBUS supply is being described
+ *
+ * This call is used by a driver for an external transceiver (or GPIO)
+ * that detects a VBUS power session ending.  Common responses include
+ * reversing everything done in usb_gadget_vbus_connect().
+ *
+ * Returns zero on success, else negative errno.
+ */
+static inline int
+usb_gadget_vbus_disconnect(struct usb_gadget *gadget)
+{
+	if (!gadget->ops->vbus_session)
+		return -EOPNOTSUPP;
+	return gadget->ops->vbus_session (gadget, 0);
+}
+
+/**
+ * usb_gadget_connect - software-controlled connect to USB host
+ * @gadget:the peripheral being connected
+ *
+ * Enables the D+ (or potentially D-) pullup.  The host will start
+ * enumerating this gadget when the pullup is active and a VBUS session
+ * is active (the link is powered).  This pullup is always enabled unless
+ * usb_gadget_disconnect() has been used to disable it.
+ *
+ * Returns zero on success, else negative errno.
+ */
+static inline int
+usb_gadget_connect (struct usb_gadget *gadget)
+{
+	if (!gadget->ops->pullup)
+		return -EOPNOTSUPP;
+	return gadget->ops->pullup (gadget, 1);
+}
+
+/**
+ * usb_gadget_disconnect - software-controlled disconnect from USB host
+ * @gadget:the peripheral being disconnected
+ *
+ * Disables the D+ (or potentially D-) pullup, which the host may see
+ * as a disconnect (when a VBUS session is active).  Not all systems
+ * support software pullup controls.
+ *
+ * This routine may be used during the gadget driver bind() call to prevent
+ * the peripheral from ever being visible to the USB host, unless later
+ * usb_gadget_connect() is called.  For example, user mode components may
+ * need to be activated before the system can talk to hosts.
+ *
+ * Returns zero on success, else negative errno.
+ */
+static inline int
+usb_gadget_disconnect (struct usb_gadget *gadget)
+{
+	if (!gadget->ops->pullup)
+		return -EOPNOTSUPP;
+	return gadget->ops->pullup (gadget, 0);
+}
+
+
+
+/*-------------------------------------------------------------------------*/
+
+/**
+ * struct usb_gadget_driver - driver for usb 'slave' devices
+ * @speed: Highest speed the driver handles.
+ * @bind: Invoked when the driver is bound to a gadget, usually
+ *	after registering the driver.
+ *	At that point, ep0 is fully initialized, and ep_list holds
+ *	the currently-available endpoints.
+ *	Called in a context that permits sleeping.
+ * @setup: Invoked for ep0 control requests that aren't handled by
+ *	the hardware level driver. Most calls must be handled by
+ *	the gadget driver, including descriptor and configuration
+ *	management.  The 16 bit members of the setup data are in
+ *	USB byte order. Called in_interrupt; this may not sleep.  Driver
+ *	queues a response to ep0, or returns negative to stall.
+ * @disconnect: Invoked after all transfers have been stopped,
+ *	when the host is disconnected.  May be called in_interrupt; this
+ *	may not sleep.  Some devices can't detect disconnect, so this might
+ *	not be called except as part of controller shutdown.
+ * @unbind: Invoked when the driver is unbound from a gadget,
+ *	usually from rmmod (after a disconnect is reported).
+ *	Called in a context that permits sleeping.
+ * @suspend: Invoked on USB suspend.  May be called in_interrupt.
+ * @resume: Invoked on USB resume.  May be called in_interrupt.
+ *
+ * Devices are disabled till a gadget driver successfully bind()s, which
+ * means the driver will handle setup() requests needed to enumerate (and
+ * meet "chapter 9" requirements) then do some useful work.
+ *
+ * If gadget->is_otg is true, the gadget driver must provide an OTG
+ * descriptor during enumeration, or else fail the bind() call.  In such
+ * cases, no USB traffic may flow until both bind() returns without
+ * having called usb_gadget_disconnect(), and the USB host stack has
+ * initialized.
+ *
+ * Drivers use hardware-specific knowledge to configure the usb hardware.
+ * endpoint addressing is only one of several hardware characteristics that
+ * are in descriptors the ep0 implementation returns from setup() calls.
+ *
+ * Except for ep0 implementation, most driver code shouldn't need change to
+ * run on top of different usb controllers.  It'll use endpoints set up by
+ * that ep0 implementation.
+ *
+ * The usb controller driver handles a few standard usb requests.  Those
+ * include set_address, and feature flags for devices, interfaces, and
+ * endpoints (the get_status, set_feature, and clear_feature requests).
+ *
+ * Accordingly, the driver's setup() callback must always implement all
+ * get_descriptor requests, returning at least a device descriptor and
+ * a configuration descriptor.  Drivers must make sure the endpoint
+ * descriptors match any hardware constraints. Some hardware also constrains
+ * other descriptors. (The pxa250 allows only configurations 1, 2, or 3).
+ *
+ * The driver's setup() callback must also implement set_configuration,
+ * and should also implement set_interface, get_configuration, and
+ * get_interface.  Setting a configuration (or interface) is where
+ * endpoints should be activated or (config 0) shut down.
+ *
+ * (Note that only the default control endpoint is supported.  Neither
+ * hosts nor devices generally support control traffic except to ep0.)
+ *
+ * Most devices will ignore USB suspend/resume operations, and so will
+ * not provide those callbacks.  However, some may need to change modes
+ * when the host is not longer directing those activities.  For example,
+ * local controls (buttons, dials, etc) may need to be re-enabled since
+ * the (remote) host can't do that any longer; or an error state might
+ * be cleared, to make the device behave identically whether or not
+ * power is maintained.
+ */
+struct usb_gadget_driver {
+	enum usb_device_speed	speed;
+	int			(*bind)(struct usb_gadget *);
+	void			(*unbind)(struct usb_gadget *);
+	int			(*setup)(struct usb_gadget *,
+					const struct usb_ctrlrequest *);
+	void			(*disconnect)(struct usb_gadget *);
+	void			(*suspend)(struct usb_gadget *);
+	void			(*resume)(struct usb_gadget *);
+};
+
+
+
+/*-------------------------------------------------------------------------*/
+
+/* driver modules register and unregister, as usual.
+ * these calls must be made in a context that can sleep.
+ *
+ * these will usually be implemented directly by the hardware-dependent
+ * usb bus interface driver, which will only support a single driver.
+ */
+
+/**
+ * usb_gadget_register_driver - register a gadget driver
+ * @driver:the driver being registered
+ *
+ * Call this in your gadget driver's module initialization function,
+ * to tell the underlying usb controller driver about your driver.
+ * The driver's bind() function will be called to bind it to a
+ * gadget before this registration call returns.  It's expected that
+ * the bind() functions will be in init sections.
+ * This function must be called in a context that can sleep.
+ */
+int usb_gadget_register_driver (struct usb_gadget_driver *driver);
+
+/**
+ * usb_gadget_unregister_driver - unregister a gadget driver
+ * @driver:the driver being unregistered
+ *
+ * Call this in your gadget driver's module cleanup function,
+ * to tell the underlying usb controller that your driver is
+ * going away.  If the controller is connected to a USB host,
+ * it will first disconnect().  The driver is also requested
+ * to unbind() and clean up any device state, before this procedure
+ * finally returns.  It's expected that the unbind() functions
+ * will in in exit sections, so may not be linked in some kernels.
+ * This function must be called in a context that can sleep.
+ */
+int usb_gadget_unregister_driver (struct usb_gadget_driver *driver);
+
+/*-------------------------------------------------------------------------*/
+
+/* utility to simplify dealing with string descriptors */
+
+/**
+ * struct usb_string - wraps a C string and its USB id
+ * @id:the (nonzero) ID for this string
+ * @s:the string, in UTF-8 encoding
+ *
+ * If you're using usb_gadget_get_string(), use this to wrap a string
+ * together with its ID.
+ */
+struct usb_string {
+	u8			id;
+	const char		*s;
+};
+
+/**
+ * struct usb_gadget_strings - a set of USB strings in a given language
+ * @language:identifies the strings' language (0x0409 for en-us)
+ * @strings:array of strings with their ids
+ *
+ * If you're using usb_gadget_get_string(), use this to wrap all the
+ * strings for a given language.
+ */
+struct usb_gadget_strings {
+	u16			language;	/* 0x0409 for en-us */
+	struct usb_string	*strings;
+};
+
+/* put descriptor for string with that id into buf (buflen >= 256) */
+int usb_gadget_get_string (struct usb_gadget_strings *table, int id, u8 *buf);
+
+/*-------------------------------------------------------------------------*/
+
+/* utility to simplify managing config descriptors */
+
+/* write vector of descriptors into buffer */
+int usb_descriptor_fillbuf(void *, unsigned,
+		const struct usb_descriptor_header **);
+
+/* build config descriptor from single descriptor vector */
+int usb_gadget_config_buf(const struct usb_config_descriptor *config,
+	void *buf, unsigned buflen, const struct usb_descriptor_header **desc);
+
+/*-------------------------------------------------------------------------*/
+
+/* utility wrapping a simple endpoint selection policy */
+
+extern struct usb_ep *usb_ep_autoconfig (struct usb_gadget *,
+			struct usb_endpoint_descriptor *);
+
+extern void usb_ep_autoconfig_reset (struct usb_gadget *);
+
+extern int usb_gadget_handle_interrupts(void);
+
+#endif	/* __LINUX_USB_GADGET_H */