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>

6 files changed, 2728 insertions, 0 deletions

diff --git a/drivers/usb/gadget/Makefile b/drivers/usb/gadget/Makefile
index 1d7362dc97..9b1b55b41b 100644
--- a/drivers/usb/gadget/Makefile
+++ b/drivers/usb/gadget/Makefile
@@ -25,6 +25,7 @@ include $(TOPDIR)/config.mk
 
 LIB	:= $(obj)libusb_gadget.a
 
+# Devices not related to the new gadget layer depend on CONFIG_USB_DEVICE
 ifdef CONFIG_USB_DEVICE
 COBJS-y += core.o
 COBJS-y += ep0.o
@@ -34,6 +35,8 @@ COBJS-$(CONFIG_MPC885_FAMILY) += mpc8xx_udc.o
 COBJS-$(CONFIG_PXA27X) += pxa27x_udc.o
 COBJS-$(CONFIG_SPEARUDC) += spr_udc.o
 endif
+# new USB gadget layer dependencies
+COBJS-$(CONFIG_USB_ETHER) += ether.o epautoconf.o config.o usbstring.o
 
 COBJS	:= $(COBJS-y)
 SRCS	:= $(COBJS:.o=.c)
diff --git a/drivers/usb/gadget/config.c b/drivers/usb/gadget/config.c
new file mode 100644
index 0000000000..84c90f0dcf
--- /dev/null
+++ b/drivers/usb/gadget/config.c
@@ -0,0 +1,119 @@
+/*
+ * usb/gadget/config.c -- simplify building config descriptors
+ *
+ * Copyright (C) 2003 David Brownell
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Ported to U-boot by: Thomas Smits <ts.smits@gmail.com> and
+ *                      Remy Bohmer <linux@bohmer.net>
+ */
+
+#include <common.h>
+#include <asm/errno.h>
+#include <linux/list.h>
+#include <linux/string.h>
+
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+
+
+/**
+ * usb_descriptor_fillbuf - fill buffer with descriptors
+ * @buf: Buffer to be filled
+ * @buflen: Size of buf
+ * @src: Array of descriptor pointers, terminated by null pointer.
+ *
+ * Copies descriptors into the buffer, returning the length or a
+ * negative error code if they can't all be copied.  Useful when
+ * assembling descriptors for an associated set of interfaces used
+ * as part of configuring a composite device; or in other cases where
+ * sets of descriptors need to be marshaled.
+ */
+int
+usb_descriptor_fillbuf(void *buf, unsigned buflen,
+		const struct usb_descriptor_header **src)
+{
+	u8	*dest = buf;
+
+	if (!src)
+		return -EINVAL;
+
+	/* fill buffer from src[] until null descriptor ptr */
+	for (; NULL != *src; src++) {
+		unsigned		len = (*src)->bLength;
+
+		if (len > buflen)
+			return -EINVAL;
+		memcpy(dest, *src, len);
+		buflen -= len;
+		dest += len;
+	}
+	return dest - (u8 *)buf;
+}
+
+
+/**
+ * usb_gadget_config_buf - builts a complete configuration descriptor
+ * @config: Header for the descriptor, including characteristics such
+ *	as power requirements and number of interfaces.
+ * @desc: Null-terminated vector of pointers to the descriptors (interface,
+ *	endpoint, etc) defining all functions in this device configuration.
+ * @buf: Buffer for the resulting configuration descriptor.
+ * @length: Length of buffer.  If this is not big enough to hold the
+ *	entire configuration descriptor, an error code will be returned.
+ *
+ * This copies descriptors into the response buffer, building a descriptor
+ * for that configuration.  It returns the buffer length or a negative
+ * status code.  The config.wTotalLength field is set to match the length
+ * of the result, but other descriptor fields (including power usage and
+ * interface count) must be set by the caller.
+ *
+ * Gadget drivers could use this when constructing a config descriptor
+ * in response to USB_REQ_GET_DESCRIPTOR.  They will need to patch the
+ * resulting bDescriptorType value if USB_DT_OTHER_SPEED_CONFIG is needed.
+ */
+int usb_gadget_config_buf(
+	const struct usb_config_descriptor	*config,
+	void					*buf,
+	unsigned				length,
+	const struct usb_descriptor_header	**desc
+)
+{
+	struct usb_config_descriptor		*cp = buf;
+	int					len;
+
+	/* config descriptor first */
+	if (length < USB_DT_CONFIG_SIZE || !desc)
+		return -EINVAL;
+	*cp = *config;
+
+	/* then interface/endpoint/class/vendor/... */
+	len = usb_descriptor_fillbuf(USB_DT_CONFIG_SIZE + (u8*)buf,
+			length - USB_DT_CONFIG_SIZE, desc);
+	if (len < 0)
+		return len;
+	len += USB_DT_CONFIG_SIZE;
+	if (len > 0xffff)
+		return -EINVAL;
+
+	/* patch up the config descriptor */
+	cp->bLength = USB_DT_CONFIG_SIZE;
+	cp->bDescriptorType = USB_DT_CONFIG;
+	cp->wTotalLength = cpu_to_le16(len);
+	cp->bmAttributes |= USB_CONFIG_ATT_ONE;
+	return len;
+}
+
diff --git a/drivers/usb/gadget/epautoconf.c b/drivers/usb/gadget/epautoconf.c
new file mode 100644
index 0000000000..c7fad3992e
--- /dev/null
+++ b/drivers/usb/gadget/epautoconf.c
@@ -0,0 +1,306 @@
+/*
+ * epautoconf.c -- endpoint autoconfiguration for usb gadget drivers
+ *
+ * Copyright (C) 2004 David Brownell
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Ported to U-boot by: Thomas Smits <ts.smits@gmail.com> and
+ *                      Remy Bohmer <linux@bohmer.net>
+ */
+
+#include <common.h>
+#include <linux/usb/ch9.h>
+#include <asm/errno.h>
+#include <linux/usb/gadget.h>
+#include "gadget_chips.h"
+
+#define isdigit(c)      ('0' <= (c) && (c) <= '9')
+
+/* we must assign addresses for configurable endpoints (like net2280) */
+static unsigned epnum;
+
+// #define MANY_ENDPOINTS
+#ifdef MANY_ENDPOINTS
+/* more than 15 configurable endpoints */
+static unsigned in_epnum;
+#endif
+
+
+/*
+ * This should work with endpoints from controller drivers sharing the
+ * same endpoint naming convention.  By example:
+ *
+ *	- ep1, ep2, ... address is fixed, not direction or type
+ *	- ep1in, ep2out, ... address and direction are fixed, not type
+ *	- ep1-bulk, ep2-bulk, ... address and type are fixed, not direction
+ *	- ep1in-bulk, ep2out-iso, ... all three are fixed
+ *	- ep-* ... no functionality restrictions
+ *
+ * Type suffixes are "-bulk", "-iso", or "-int".  Numbers are decimal.
+ * Less common restrictions are implied by gadget_is_*().
+ *
+ * NOTE:  each endpoint is unidirectional, as specified by its USB
+ * descriptor; and isn't specific to a configuration or altsetting.
+ */
+static int
+ep_matches (
+	struct usb_gadget		*gadget,
+	struct usb_ep			*ep,
+	struct usb_endpoint_descriptor	*desc
+)
+{
+	u8		type;
+	const char	*tmp;
+	u16		max;
+
+	/* endpoint already claimed? */
+	if (NULL != ep->driver_data)
+		return 0;
+
+	/* only support ep0 for portable CONTROL traffic */
+	type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
+	if (USB_ENDPOINT_XFER_CONTROL == type)
+		return 0;
+
+	/* some other naming convention */
+	if ('e' != ep->name[0])
+		return 0;
+
+	/* type-restriction:  "-iso", "-bulk", or "-int".
+	 * direction-restriction:  "in", "out".
+	 */
+	if ('-' != ep->name[2]) {
+		tmp = strrchr (ep->name, '-');
+		if (tmp) {
+			switch (type) {
+			case USB_ENDPOINT_XFER_INT:
+				/* bulk endpoints handle interrupt transfers,
+				 * except the toggle-quirky iso-synch kind
+				 */
+				if ('s' == tmp[2])	// == "-iso"
+					return 0;
+				/* for now, avoid PXA "interrupt-in";
+				 * it's documented as never using DATA1.
+				 */
+				if (gadget_is_pxa (gadget)
+						&& 'i' == tmp [1])
+					return 0;
+				break;
+			case USB_ENDPOINT_XFER_BULK:
+				if ('b' != tmp[1])	// != "-bulk"
+					return 0;
+				break;
+			case USB_ENDPOINT_XFER_ISOC:
+				if ('s' != tmp[2])	// != "-iso"
+					return 0;
+			}
+		} else {
+			tmp = ep->name + strlen (ep->name);
+		}
+
+		/* direction-restriction:  "..in-..", "out-.." */
+		tmp--;
+		if (!isdigit (*tmp)) {
+			if (desc->bEndpointAddress & USB_DIR_IN) {
+				if ('n' != *tmp)
+					return 0;
+			} else {
+				if ('t' != *tmp)
+					return 0;
+			}
+		}
+	}
+
+	/* endpoint maxpacket size is an input parameter, except for bulk
+	 * where it's an output parameter representing the full speed limit.
+	 * the usb spec fixes high speed bulk maxpacket at 512 bytes.
+	 */
+	max = 0x7ff & le16_to_cpu(desc->wMaxPacketSize);
+	switch (type) {
+	case USB_ENDPOINT_XFER_INT:
+		/* INT:  limit 64 bytes full speed, 1024 high speed */
+		if (!gadget->is_dualspeed && max > 64)
+			return 0;
+		/* FALLTHROUGH */
+
+	case USB_ENDPOINT_XFER_ISOC:
+		/* ISO:  limit 1023 bytes full speed, 1024 high speed */
+		if (ep->maxpacket < max)
+			return 0;
+		if (!gadget->is_dualspeed && max > 1023)
+			return 0;
+
+		/* BOTH:  "high bandwidth" works only at high speed */
+		if ((desc->wMaxPacketSize & __constant_cpu_to_le16(3<<11))) {
+			if (!gadget->is_dualspeed)
+				return 0;
+			/* configure your hardware with enough buffering!! */
+		}
+		break;
+	}
+
+	/* MATCH!! */
+
+	/* report address */
+	if (isdigit (ep->name [2])) {
+		u8	num = simple_strtol (&ep->name [2], NULL, 10);
+		desc->bEndpointAddress |= num;
+#ifdef	MANY_ENDPOINTS
+	} else if (desc->bEndpointAddress & USB_DIR_IN) {
+		if (++in_epnum > 15)
+			return 0;
+		desc->bEndpointAddress = USB_DIR_IN | in_epnum;
+#endif
+	} else {
+		if (++epnum > 15)
+			return 0;
+		desc->bEndpointAddress |= epnum;
+	}
+
+	/* report (variable) full speed bulk maxpacket */
+	if (USB_ENDPOINT_XFER_BULK == type) {
+		int size = ep->maxpacket;
+
+		/* min() doesn't work on bitfields with gcc-3.5 */
+		if (size > 64)
+			size = 64;
+		desc->wMaxPacketSize = cpu_to_le16(size);
+	}
+	return 1;
+}
+
+static struct usb_ep *
+find_ep (struct usb_gadget *gadget, const char *name)
+{
+	struct usb_ep	*ep;
+
+	list_for_each_entry (ep, &gadget->ep_list, ep_list) {
+		if (0 == strcmp (ep->name, name))
+			return ep;
+	}
+	return NULL;
+}
+
+/**
+ * usb_ep_autoconfig - choose an endpoint matching the descriptor
+ * @gadget: The device to which the endpoint must belong.
+ * @desc: Endpoint descriptor, with endpoint direction and transfer mode
+ *	initialized.  For periodic transfers, the maximum packet
+ *	size must also be initialized.  This is modified on success.
+ *
+ * By choosing an endpoint to use with the specified descriptor, this
+ * routine simplifies writing gadget drivers that work with multiple
+ * USB device controllers.  The endpoint would be passed later to
+ * usb_ep_enable(), along with some descriptor.
+ *
+ * That second descriptor won't always be the same as the first one.
+ * For example, isochronous endpoints can be autoconfigured for high
+ * bandwidth, and then used in several lower bandwidth altsettings.
+ * Also, high and full speed descriptors will be different.
+ *
+ * Be sure to examine and test the results of autoconfiguration on your
+ * hardware.  This code may not make the best choices about how to use the
+ * USB controller, and it can't know all the restrictions that may apply.
+ * Some combinations of driver and hardware won't be able to autoconfigure.
+ *
+ * On success, this returns an un-claimed usb_ep, and modifies the endpoint
+ * descriptor bEndpointAddress.  For bulk endpoints, the wMaxPacket value
+ * is initialized as if the endpoint were used at full speed.  To prevent
+ * the endpoint from being returned by a later autoconfig call, claim it
+ * by assigning ep->driver_data to some non-null value.
+ *
+ * On failure, this returns a null endpoint descriptor.
+ */
+struct usb_ep * usb_ep_autoconfig (
+	struct usb_gadget		*gadget,
+	struct usb_endpoint_descriptor	*desc
+)
+{
+	struct usb_ep	*ep;
+	u8		type;
+
+	type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
+
+	/* First, apply chip-specific "best usage" knowledge.
+	 * This might make a good usb_gadget_ops hook ...
+	 */
+	if (gadget_is_net2280 (gadget) && type == USB_ENDPOINT_XFER_INT) {
+		/* ep-e, ep-f are PIO with only 64 byte fifos */
+		ep = find_ep (gadget, "ep-e");
+		if (ep && ep_matches (gadget, ep, desc))
+			return ep;
+		ep = find_ep (gadget, "ep-f");
+		if (ep && ep_matches (gadget, ep, desc))
+			return ep;
+
+	} else if (gadget_is_goku (gadget)) {
+		if (USB_ENDPOINT_XFER_INT == type) {
+			/* single buffering is enough */
+			ep = find_ep (gadget, "ep3-bulk");
+			if (ep && ep_matches (gadget, ep, desc))
+				return ep;
+		} else if (USB_ENDPOINT_XFER_BULK == type
+				&& (USB_DIR_IN & desc->bEndpointAddress)) {
+			/* DMA may be available */
+			ep = find_ep (gadget, "ep2-bulk");
+			if (ep && ep_matches (gadget, ep, desc))
+				return ep;
+		}
+
+	} else if (gadget_is_sh (gadget) && USB_ENDPOINT_XFER_INT == type) {
+		/* single buffering is enough; maybe 8 byte fifo is too */
+		ep = find_ep (gadget, "ep3in-bulk");
+		if (ep && ep_matches (gadget, ep, desc))
+			return ep;
+
+	} else if (gadget_is_mq11xx (gadget) && USB_ENDPOINT_XFER_INT == type) {
+		ep = find_ep (gadget, "ep1-bulk");
+		if (ep && ep_matches (gadget, ep, desc))
+			return ep;
+	}
+
+	/* Second, look at endpoints until an unclaimed one looks usable */
+	list_for_each_entry (ep, &gadget->ep_list, ep_list) {
+		if (ep_matches (gadget, ep, desc))
+			return ep;
+	}
+
+	/* Fail */
+	return NULL;
+}
+
+/**
+ * usb_ep_autoconfig_reset - reset endpoint autoconfig state
+ * @gadget: device for which autoconfig state will be reset
+ *
+ * Use this for devices where one configuration may need to assign
+ * endpoint resources very differently from the next one.  It clears
+ * state such as ep->driver_data and the record of assigned endpoints
+ * used by usb_ep_autoconfig().
+ */
+void usb_ep_autoconfig_reset (struct usb_gadget *gadget)
+{
+	struct usb_ep	*ep;
+
+	list_for_each_entry (ep, &gadget->ep_list, ep_list) {
+		ep->driver_data = NULL;
+	}
+#ifdef	MANY_ENDPOINTS
+	in_epnum = 0;
+#endif
+	epnum = 0;
+}
+
diff --git a/drivers/usb/gadget/ether.c b/drivers/usb/gadget/ether.c
new file mode 100644
index 0000000000..3d871fa10e
--- /dev/null
+++ b/drivers/usb/gadget/ether.c
@@ -0,0 +1,1947 @@
+/*
+ * ether.c -- Ethernet gadget driver, with CDC and non-CDC options
+ *
+ * Copyright (C) 2003-2005,2008 David Brownell
+ * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <common.h>
+#include <asm/errno.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/cdc.h>
+#include <linux/usb/gadget.h>
+#include <net.h>
+#include <linux/ctype.h>
+
+#include "gadget_chips.h"
+
+#define USB_NET_NAME "usb0"
+#define dprintf(x, ...)
+#undef INFO
+#define INFO(x, s...)	printf(s)
+#define dev_err(x, stuff...) printf(stuff)
+#define dev_dbg dev_err
+#define dev_warn dev_err
+#define DEBUG dev_err
+#define VDEBUG DEBUG
+#define atomic_read
+extern struct platform_data brd;
+#define spin_lock(x)
+#define spin_unlock(x)
+
+
+unsigned packet_received, packet_sent;
+
+#define DEV_CONFIG_CDC	1
+#define GFP_ATOMIC ((gfp_t) 0)
+#define GFP_KERNEL ((gfp_t) 0)
+
+/*
+ * Ethernet gadget driver -- with CDC and non-CDC options
+ * Builds on hardware support for a full duplex link.
+ *
+ * CDC Ethernet is the standard USB solution for sending Ethernet frames
+ * using USB.  Real hardware tends to use the same framing protocol but look
+ * different for control features.  This driver strongly prefers to use
+ * this USB-IF standard as its open-systems interoperability solution;
+ * most host side USB stacks (except from Microsoft) support it.
+ *
+ * This is sometimes called "CDC ECM" (Ethernet Control Model) to support
+ * TLA-soup.  "CDC ACM" (Abstract Control Model) is for modems, and a new
+ * "CDC EEM" (Ethernet Emulation Model) is starting to spread.
+ *
+ * There's some hardware that can't talk CDC ECM.  We make that hardware
+ * implement a "minimalist" vendor-agnostic CDC core:  same framing, but
+ * link-level setup only requires activating the configuration.  Only the
+ * endpoint descriptors, and product/vendor IDs, are relevant; no control
+ * operations are available.  Linux supports it, but other host operating
+ * systems may not.  (This is a subset of CDC Ethernet.)
+ *
+ * It turns out that if you add a few descriptors to that "CDC Subset",
+ * (Windows) host side drivers from MCCI can treat it as one submode of
+ * a proprietary scheme called "SAFE" ... without needing to know about
+ * specific product/vendor IDs.  So we do that, making it easier to use
+ * those MS-Windows drivers.  Those added descriptors make it resemble a
+ * CDC MDLM device, but they don't change device behavior at all.  (See
+ * MCCI Engineering report 950198 "SAFE Networking Functions".)
+ *
+ * A third option is also in use.  Rather than CDC Ethernet, or something
+ * simpler, Microsoft pushes their own approach: RNDIS.  The published
+ * RNDIS specs are ambiguous and appear to be incomplete, and are also
+ * needlessly complex.  They borrow more from CDC ACM than CDC ECM.
+ */
+#define ETH_ALEN	6		/* Octets in one ethernet addr	 */
+#define ETH_HLEN	14		/* Total octets in header.	 */
+#define ETH_ZLEN	60		/* Min. octets in frame sans FCS */
+#define ETH_DATA_LEN	1500		/* Max. octets in payload	 */
+#define ETH_FRAME_LEN	PKTSIZE_ALIGN	/* Max. octets in frame sans FCS */
+#define ETH_FCS_LEN	4		/* Octets in the FCS		 */
+
+#define DRIVER_DESC		"Ethernet Gadget"
+/* Based on linux 2.6.27 version */
+#define DRIVER_VERSION		"May Day 2005"
+
+static const char shortname [] = "ether";
+static const char driver_desc [] = DRIVER_DESC;
+
+#define RX_EXTRA	20		/* guard against rx overflows */
+
+/* CDC support the same host-chosen outgoing packet filters. */
+#define	DEFAULT_FILTER	(USB_CDC_PACKET_TYPE_BROADCAST \
+			|USB_CDC_PACKET_TYPE_ALL_MULTICAST \
+			|USB_CDC_PACKET_TYPE_PROMISCUOUS \
+			|USB_CDC_PACKET_TYPE_DIRECTED)
+
+#define USB_CONNECT_TIMEOUT (3 * CONFIG_SYS_HZ)
+
+/*-------------------------------------------------------------------------*/
+static struct eth_dev l_ethdev;
+static struct eth_device l_netdev;
+static struct usb_gadget_driver eth_driver;
+
+/*-------------------------------------------------------------------------*/
+
+/* "main" config is either CDC, or its simple subset */
+static inline int is_cdc(struct eth_dev *dev)
+{
+#if	!defined(DEV_CONFIG_SUBSET)
+	return 1;		/* only cdc possible */
+#elif	!defined (DEV_CONFIG_CDC)
+	return 0;		/* only subset possible */
+#else
+	return dev->cdc;	/* depends on what hardware we found */
+#endif
+}
+
+#define	subset_active(dev)	(!is_cdc(dev))
+#define	cdc_active(dev)		( is_cdc(dev))
+
+#define DEFAULT_QLEN	2	/* double buffering by default */
+
+/* peak bulk transfer bits-per-second */
+#define	HS_BPS		(13 * 512 * 8 * 1000 * 8)
+#define	FS_BPS		(19 *  64 * 1 * 1000 * 8)
+
+#ifdef CONFIG_USB_GADGET_DUALSPEED
+#define	DEVSPEED	USB_SPEED_HIGH
+
+/* for dual-speed hardware, use deeper queues at highspeed */
+#define qlen(gadget) \
+	(DEFAULT_QLEN*((gadget->speed == USB_SPEED_HIGH) ? qmult : 1))
+
+static inline int BITRATE(struct usb_gadget *g)
+{
+	return (g->speed == USB_SPEED_HIGH) ? HS_BPS : FS_BPS;
+}
+
+#else	/* full speed (low speed doesn't do bulk) */
+
+#define qmult		1
+
+#define	DEVSPEED	USB_SPEED_FULL
+
+#define qlen(gadget) DEFAULT_QLEN
+
+static inline int BITRATE(struct usb_gadget *g)
+{
+	return FS_BPS;
+}
+#endif
+
+struct eth_dev {
+	struct usb_gadget	*gadget;
+	struct usb_request	*req;		/* for control responses */
+	struct usb_request	*stat_req;	/* for cdc status */
+
+	u8			config;
+	struct usb_ep		*in_ep, *out_ep, *status_ep;
+	const struct usb_endpoint_descriptor
+				*in, *out, *status;
+
+	struct usb_request	*tx_req, *rx_req;
+
+	struct eth_device	*net;
+	unsigned int		tx_qlen;
+
+	unsigned		zlp:1;
+	unsigned		cdc:1;
+	unsigned		suspended:1;
+	unsigned 		network_started:1;
+	u16			cdc_filter;
+	unsigned long		todo;
+	int 			mtu;
+#define	WORK_RX_MEMORY		0
+	u8			host_mac [ETH_ALEN];
+};
+
+/* This version autoconfigures as much as possible at run-time.
+ *
+ * It also ASSUMES a self-powered device, without remote wakeup,
+ * although remote wakeup support would make sense.
+ */
+
+/*-------------------------------------------------------------------------*/
+
+/* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
+ * Instead:  allocate your own, using normal USB-IF procedures.
+ */
+
+/* Thanks to NetChip Technologies for donating this product ID.
+ * It's for devices with only CDC Ethernet configurations.
+ */
+#define CDC_VENDOR_NUM		0x0525	/* NetChip */
+#define CDC_PRODUCT_NUM		0xa4a1	/* Linux-USB Ethernet Gadget */
+
+/* For hardware that can't talk CDC, we use the same vendor ID that
+ * ARM Linux has used for ethernet-over-usb, both with sa1100 and
+ * with pxa250.  We're protocol-compatible, if the host-side drivers
+ * use the endpoint descriptors.  bcdDevice (version) is nonzero, so
+ * drivers that need to hard-wire endpoint numbers have a hook.
+ *
+ * The protocol is a minimal subset of CDC Ether, which works on any bulk
+ * hardware that's not deeply broken ... even on hardware that can't talk
+ * RNDIS (like SA-1100, with no interrupt endpoint, or anything that
+ * doesn't handle control-OUT).
+ */
+#define	SIMPLE_VENDOR_NUM	0x049f
+#define	SIMPLE_PRODUCT_NUM	0x505a
+
+/* Some systems will want different product identifers published in the
+ * device descriptor, either numbers or strings or both.  These string
+ * parameters are in UTF-8 (superset of ASCII's 7 bit characters).
+ */
+
+static ushort bcdDevice;
+#if defined(CONFIG_USBNET_MANUFACTURER)
+static char *iManufacturer = CONFIG_USBNET_MANUFACTURER;
+#else
+static char *iManufacturer = "U-boot";
+#endif
+static char *iProduct;
+static char *iSerialNumber;
+static char dev_addr[18];
+static char host_addr[18];
+
+/*-------------------------------------------------------------------------*/
+
+/* USB DRIVER HOOKUP (to the hardware driver, below us), mostly
+ * ep0 implementation:  descriptors, config management, setup().
+ * also optional class-specific notification interrupt transfer.
+ */
+
+/*
+ * DESCRIPTORS ... most are static, but strings and (full) configuration
+ * descriptors are built on demand.  For now we do either full CDC, or
+ * our simple subset.
+ */
+
+#define STRING_MANUFACTURER		1
+#define STRING_PRODUCT			2
+#define STRING_ETHADDR			3
+#define STRING_DATA			4
+#define STRING_CONTROL			5
+#define STRING_CDC			7
+#define STRING_SUBSET			8
+#define STRING_SERIALNUMBER		10
+
+/* holds our biggest descriptor */
+#define USB_BUFSIZ	256
+
+/*
+ * This device advertises one configuration, eth_config,
+ * on hardware supporting at least two configs.
+ *
+ * FIXME define some higher-powered configurations to make it easier
+ * to recharge batteries ...
+ */
+
+#define DEV_CONFIG_VALUE	1	/* cdc or subset */
+
+static struct usb_device_descriptor
+device_desc = {
+	.bLength =		sizeof device_desc,
+	.bDescriptorType =	USB_DT_DEVICE,
+
+	.bcdUSB =		__constant_cpu_to_le16 (0x0200),
+
+	.bDeviceClass =		USB_CLASS_COMM,
+	.bDeviceSubClass =	0,
+	.bDeviceProtocol =	0,
+
+	.idVendor =		__constant_cpu_to_le16 (CDC_VENDOR_NUM),
+	.idProduct =		__constant_cpu_to_le16 (CDC_PRODUCT_NUM),
+	.iManufacturer =	STRING_MANUFACTURER,
+	.iProduct =		STRING_PRODUCT,
+	.bNumConfigurations =	1,
+};
+
+static struct usb_otg_descriptor
+otg_descriptor = {
+	.bLength =		sizeof otg_descriptor,
+	.bDescriptorType =	USB_DT_OTG,
+
+	.bmAttributes =		USB_OTG_SRP,
+};
+
+static struct usb_config_descriptor
+eth_config = {
+	.bLength =		sizeof eth_config,
+	.bDescriptorType =	USB_DT_CONFIG,
+
+	/* compute wTotalLength on the fly */
+	.bNumInterfaces =	2,
+	.bConfigurationValue =	DEV_CONFIG_VALUE,
+	.iConfiguration =	STRING_CDC,
+	.bmAttributes =		USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
+	.bMaxPower =		1,
+};
+
+/*
+ * Compared to the simple CDC subset, the full CDC Ethernet model adds
+ * three class descriptors, two interface descriptors, optional status
+ * endpoint.  Both have a "data" interface and two bulk endpoints.
+ * There are also differences in how control requests are handled.
+ */
+
+#ifdef	DEV_CONFIG_CDC
+static struct usb_interface_descriptor
+control_intf = {
+	.bLength =		sizeof control_intf,
+	.bDescriptorType =	USB_DT_INTERFACE,
+
+	.bInterfaceNumber =	0,
+	/* status endpoint is optional; this may be patched later */
+	.bNumEndpoints =	1,
+	.bInterfaceClass =	USB_CLASS_COMM,
+	.bInterfaceSubClass =	USB_CDC_SUBCLASS_ETHERNET,
+	.bInterfaceProtocol =	USB_CDC_PROTO_NONE,
+	.iInterface =		STRING_CONTROL,
+};
+#endif
+
+static const struct usb_cdc_header_desc header_desc = {
+	.bLength =		sizeof header_desc,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubType =	USB_CDC_HEADER_TYPE,
+
+	.bcdCDC =		__constant_cpu_to_le16 (0x0110),
+};
+
+#if defined(DEV_CONFIG_CDC)
+
+static const struct usb_cdc_union_desc union_desc = {
+	.bLength =		sizeof union_desc,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubType =	USB_CDC_UNION_TYPE,
+
+	.bMasterInterface0 =	0,	/* index of control interface */
+	.bSlaveInterface0 =	1,	/* index of DATA interface */
+};
+
+#endif	/* CDC */
+
+#ifndef DEV_CONFIG_CDC
+
+/* "SAFE" loosely follows CDC WMC MDLM, violating the spec in various
+ * ways:  data endpoints live in the control interface, there's no data
+ * interface, and it's not used to talk to a cell phone radio.
+ */
+
+static const struct usb_cdc_mdlm_desc mdlm_desc = {
+	.bLength =		sizeof mdlm_desc,
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubType =	USB_CDC_MDLM_TYPE,
+
+	.bcdVersion =		__constant_cpu_to_le16(0x0100),
+	.bGUID = {
+		0x5d, 0x34, 0xcf, 0x66, 0x11, 0x18, 0x11, 0xd6,
+		0xa2, 0x1a, 0x00, 0x01, 0x02, 0xca, 0x9a, 0x7f,
+	},
+};
+
+/* since "usb_cdc_mdlm_detail_desc" is a variable length structure, we
+ * can't really use its struct.  All we do here is say that we're using
+ * the submode of "SAFE" which directly matches the CDC Subset.
+ */
+static const u8 mdlm_detail_desc[] = {
+	6,
+	USB_DT_CS_INTERFACE,
+	USB_CDC_MDLM_DETAIL_TYPE,
+
+	0,	/* "SAFE" */
+	0,	/* network control capabilities (none) */
+	0,	/* network data capabilities ("raw" encapsulation) */
+};
+
+#endif
+
+
+static const struct usb_cdc_ether_desc ether_desc = {
+	.bLength =		sizeof (ether_desc),
+	.bDescriptorType =	USB_DT_CS_INTERFACE,
+	.bDescriptorSubType =	USB_CDC_ETHERNET_TYPE,
+
+	/* this descriptor actually adds value, surprise! */
+	.iMACAddress =		STRING_ETHADDR,
+	.bmEthernetStatistics = __constant_cpu_to_le32 (0), /* no statistics */
+	.wMaxSegmentSize =	__constant_cpu_to_le16 (ETH_FRAME_LEN),
+	.wNumberMCFilters =	__constant_cpu_to_le16 (0),
+	.bNumberPowerFilters =	0,
+};
+
+
+#if defined(DEV_CONFIG_CDC)
+
+/* include the status endpoint if we can, even where it's optional.
+ * use wMaxPacketSize big enough to fit CDC_NOTIFY_SPEED_CHANGE in one
+ * packet, to simplify cancellation; and a big transfer interval, to
+ * waste less bandwidth.
+ *
+ * some drivers (like Linux 2.4 cdc-ether!) "need" it to exist even
+ * if they ignore the connect/disconnect notifications that real aether
+ * can provide.  more advanced cdc configurations might want to support
+ * encapsulated commands (vendor-specific, using control-OUT).
+ */
+
+#define LOG2_STATUS_INTERVAL_MSEC	5	/* 1 << 5 == 32 msec */
+#define STATUS_BYTECOUNT		16	/* 8 byte header + data */
+
+static struct usb_endpoint_descriptor
+fs_status_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bEndpointAddress =	USB_DIR_IN,
+	.bmAttributes =		USB_ENDPOINT_XFER_INT,
+	.wMaxPacketSize =	__constant_cpu_to_le16 (STATUS_BYTECOUNT),
+	.bInterval =		1 << LOG2_STATUS_INTERVAL_MSEC,
+};
+#endif
+
+#ifdef	DEV_CONFIG_CDC
+
+/* the default data interface has no endpoints ... */
+
+static const struct usb_interface_descriptor
+data_nop_intf = {
+	.bLength =		sizeof data_nop_intf,
+	.bDescriptorType =	USB_DT_INTERFACE,
+
+	.bInterfaceNumber =	1,
+	.bAlternateSetting =	0,
+	.bNumEndpoints =	0,
+	.bInterfaceClass =	USB_CLASS_CDC_DATA,
+	.bInterfaceSubClass =	0,
+	.bInterfaceProtocol =	0,
+};
+
+/* ... but the "real" data interface has two bulk endpoints */
+
+static const struct usb_interface_descriptor
+data_intf = {
+	.bLength =		sizeof data_intf,
+	.bDescriptorType =	USB_DT_INTERFACE,
+
+	.bInterfaceNumber =	1,
+	.bAlternateSetting =	1,
+	.bNumEndpoints =	2,
+	.bInterfaceClass =	USB_CLASS_CDC_DATA,
+	.bInterfaceSubClass =	0,
+	.bInterfaceProtocol =	0,
+	.iInterface =		STRING_DATA,
+};
+
+#endif
+
+#ifdef DEV_CONFIG_SUBSET
+
+/*
+ * "Simple" CDC-subset option is a simple vendor-neutral model that most
+ * full speed controllers can handle:  one interface, two bulk endpoints.
+ *
+ * To assist host side drivers, we fancy it up a bit, and add descriptors
+ * so some host side drivers will understand it as a "SAFE" variant.
+ */
+
+static const struct usb_interface_descriptor
+subset_data_intf = {
+	.bLength =		sizeof subset_data_intf,
+	.bDescriptorType =	USB_DT_INTERFACE,
+
+	.bInterfaceNumber =	0,
+	.bAlternateSetting =	0,
+	.bNumEndpoints =	2,
+	.bInterfaceClass =      USB_CLASS_COMM,
+	.bInterfaceSubClass =	USB_CDC_SUBCLASS_MDLM,
+	.bInterfaceProtocol =	0,
+	.iInterface =		STRING_DATA,
+};
+
+#endif	/* SUBSET */
+
+
+static struct usb_endpoint_descriptor
+fs_source_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bEndpointAddress =	USB_DIR_IN,
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+};
+
+static struct usb_endpoint_descriptor
+fs_sink_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bEndpointAddress =	USB_DIR_OUT,
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+};
+
+static const struct usb_descriptor_header *fs_eth_function [11] = {
+	(struct usb_descriptor_header *) &otg_descriptor,
+#ifdef DEV_CONFIG_CDC
+	/* "cdc" mode descriptors */
+	(struct usb_descriptor_header *) &control_intf,
+	(struct usb_descriptor_header *) &header_desc,
+	(struct usb_descriptor_header *) &union_desc,
+	(struct usb_descriptor_header *) &ether_desc,
+	/* NOTE: status endpoint may need to be removed */
+	(struct usb_descriptor_header *) &fs_status_desc,
+	/* data interface, with altsetting */
+	(struct usb_descriptor_header *) &data_nop_intf,
+	(struct usb_descriptor_header *) &data_intf,
+	(struct usb_descriptor_header *) &fs_source_desc,
+	(struct usb_descriptor_header *) &fs_sink_desc,
+	NULL,
+#endif /* DEV_CONFIG_CDC */
+};
+
+static inline void fs_subset_descriptors(void)
+{
+#ifdef DEV_CONFIG_SUBSET
+	/* behavior is "CDC Subset"; extra descriptors say "SAFE" */
+	fs_eth_function[1] = (struct usb_descriptor_header *) &subset_data_intf;
+	fs_eth_function[2] = (struct usb_descriptor_header *) &header_desc;
+	fs_eth_function[3] = (struct usb_descriptor_header *) &mdlm_desc;
+	fs_eth_function[4] = (struct usb_descriptor_header *) &mdlm_detail_desc;
+	fs_eth_function[5] = (struct usb_descriptor_header *) &ether_desc;
+	fs_eth_function[6] = (struct usb_descriptor_header *) &fs_source_desc;
+	fs_eth_function[7] = (struct usb_descriptor_header *) &fs_sink_desc;
+	fs_eth_function[8] = NULL;
+#else
+	fs_eth_function[1] = NULL;
+#endif
+}
+
+/*
+ * usb 2.0 devices need to expose both high speed and full speed
+ * descriptors, unless they only run at full speed.
+ */
+
+#if defined(DEV_CONFIG_CDC)
+static struct usb_endpoint_descriptor
+hs_status_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_INT,
+	.wMaxPacketSize =	__constant_cpu_to_le16 (STATUS_BYTECOUNT),
+	.bInterval =		LOG2_STATUS_INTERVAL_MSEC + 4,
+};
+#endif /* DEV_CONFIG_CDC */
+
+static struct usb_endpoint_descriptor
+hs_source_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize =	__constant_cpu_to_le16 (512),
+};
+
+static struct usb_endpoint_descriptor
+hs_sink_desc = {
+	.bLength =		USB_DT_ENDPOINT_SIZE,
+	.bDescriptorType =	USB_DT_ENDPOINT,
+
+	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
+	.wMaxPacketSize =	__constant_cpu_to_le16 (512),
+};
+
+static struct usb_qualifier_descriptor
+dev_qualifier = {
+	.bLength =		sizeof dev_qualifier,
+	.bDescriptorType =	USB_DT_DEVICE_QUALIFIER,
+
+	.bcdUSB =		__constant_cpu_to_le16 (0x0200),
+	.bDeviceClass =		USB_CLASS_COMM,
+
+	.bNumConfigurations =	1,
+};
+
+static const struct usb_descriptor_header *hs_eth_function [11] = {
+	(struct usb_descriptor_header *) &otg_descriptor,
+#ifdef DEV_CONFIG_CDC
+	/* "cdc" mode descriptors */
+	(struct usb_descriptor_header *) &control_intf,
+	(struct usb_descriptor_header *) &header_desc,
+	(struct usb_descriptor_header *) &union_desc,
+	(struct usb_descriptor_header *) &ether_desc,
+	/* NOTE: status endpoint may need to be removed */
+	(struct usb_descriptor_header *) &hs_status_desc,
+	/* data interface, with altsetting */
+	(struct usb_descriptor_header *) &data_nop_intf,
+	(struct usb_descriptor_header *) &data_intf,
+	(struct usb_descriptor_header *) &hs_source_desc,
+	(struct usb_descriptor_header *) &hs_sink_desc,
+	NULL,
+#endif /* DEV_CONFIG_CDC */
+};
+
+static inline void hs_subset_descriptors(void)
+{
+#ifdef DEV_CONFIG_SUBSET
+	/* behavior is "CDC Subset"; extra descriptors say "SAFE" */
+	hs_eth_function[1] = (struct usb_descriptor_header *) &subset_data_intf;
+	hs_eth_function[2] = (struct usb_descriptor_header *) &header_desc;
+	hs_eth_function[3] = (struct usb_descriptor_header *) &mdlm_desc;
+	hs_eth_function[4] = (struct usb_descriptor_header *) &mdlm_detail_desc;
+	hs_eth_function[5] = (struct usb_descriptor_header *) &ether_desc;
+	hs_eth_function[6] = (struct usb_descriptor_header *) &hs_source_desc;
+	hs_eth_function[7] = (struct usb_descriptor_header *) &hs_sink_desc;
+	hs_eth_function[8] = NULL;
+#else
+	hs_eth_function[1] = NULL;
+#endif
+}
+
+/* maxpacket and other transfer characteristics vary by speed. */
+static inline struct usb_endpoint_descriptor *
+ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *hs,
+		struct usb_endpoint_descriptor *fs)
+{
+	if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
+		return hs;
+	return fs;
+}
+
+
+/*-------------------------------------------------------------------------*/
+
+/* descriptors that are built on-demand */
+
+static char manufacturer [50];
+static char product_desc [40] = DRIVER_DESC;
+static char serial_number [20];
+
+/* address that the host will use ... usually assigned at random */
+static char ethaddr [2 * ETH_ALEN + 1];
+
+/* static strings, in UTF-8 */
+static struct usb_string		strings [] = {
+	{ STRING_MANUFACTURER,	manufacturer, },
+	{ STRING_PRODUCT,	product_desc, },
+	{ STRING_SERIALNUMBER,	serial_number, },
+	{ STRING_DATA,		"Ethernet Data", },
+	{ STRING_ETHADDR,	ethaddr, },
+#ifdef	DEV_CONFIG_CDC
+	{ STRING_CDC,		"CDC Ethernet", },
+	{ STRING_CONTROL,	"CDC Communications Control", },
+#endif
+#ifdef	DEV_CONFIG_SUBSET
+	{ STRING_SUBSET,	"CDC Ethernet Subset", },
+#endif
+	{  }		/* end of list */
+};
+
+static struct usb_gadget_strings	stringtab = {
+	.language	= 0x0409,	/* en-us */
+	.strings	= strings,
+};
+
+
+/*============================================================================*/
+static u8 control_req[USB_BUFSIZ];
+static u8 status_req[STATUS_BYTECOUNT];
+
+
+
+/**
+ * strlcpy - Copy a %NUL terminated string into a sized buffer
+ * @dest: Where to copy the string to
+ * @src: Where to copy the string from
+ * @size: size of destination buffer
+ *
+ * Compatible with *BSD: the result is always a valid
+ * NUL-terminated string that fits in the buffer (unless,
+ * of course, the buffer size is zero). It does not pad
+ * out the result like strncpy() does.
+ */
+size_t strlcpy(char *dest, const char *src, size_t size)
+{
+	size_t ret = strlen(src);
+
+	if (size) {
+		size_t len = (ret >= size) ? size - 1 : ret;
+		memcpy(dest, src, len);
+		dest[len] = '\0';
+	}
+	return ret;
+}
+
+
+/*============================================================================*/
+
+/*
+ * one config, two interfaces:  control, data.
+ * complications: class descriptors, and an altsetting.
+ */
+static int
+config_buf(struct usb_gadget *g, u8 *buf, u8 type, unsigned index, int is_otg)
+{
+	int					len;
+	const struct usb_config_descriptor	*config;
+	const struct usb_descriptor_header	**function;
+	int					hs = 0;
+
+	if (gadget_is_dualspeed(g)) {
+		hs = (g->speed == USB_SPEED_HIGH);
+		if (type == USB_DT_OTHER_SPEED_CONFIG)
+			hs = !hs;
+	}
+#define which_fn(t)	(hs ? hs_ ## t ## _function : fs_ ## t ## _function)
+
+	if (index >= device_desc.bNumConfigurations)
+		return -EINVAL;
+
+	config = &eth_config;
+	function = which_fn (eth);
+
+	/* for now, don't advertise srp-only devices */
+	if (!is_otg)
+		function++;
+
+	len = usb_gadget_config_buf (config, buf, USB_BUFSIZ, function);
+	if (len < 0)
+		return len;
+	((struct usb_config_descriptor *) buf)->bDescriptorType = type;
+	return len;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int alloc_requests (struct eth_dev *dev, unsigned n, gfp_t gfp_flags);
+
+static int
+set_ether_config (struct eth_dev *dev, gfp_t gfp_flags)
+{
+	int					result = 0;
+	struct usb_gadget			*gadget = dev->gadget;
+
+#if defined(DEV_CONFIG_CDC)
+	/* status endpoint used for (optionally) CDC */
+	if (!subset_active(dev) && dev->status_ep) {
+		dev->status = ep_desc (gadget, &hs_status_desc,
+						&fs_status_desc);
+		dev->status_ep->driver_data = dev;
+
+		result = usb_ep_enable (dev->status_ep, dev->status);
+		if (result != 0) {
+			printf ("enable %s --> %d\n",
+				dev->status_ep->name, result);
+			goto done;
+		}
+	}
+#endif
+
+	dev->in = ep_desc(gadget, &hs_source_desc, &fs_source_desc);
+	dev->in_ep->driver_data = dev;
+
+	dev->out = ep_desc(gadget, &hs_sink_desc, &fs_sink_desc);
+	dev->out_ep->driver_data = dev;
+
+	/* With CDC,  the host isn't allowed to use these two data
+	 * endpoints in the default altsetting for the interface.
+	 * so we don't activate them yet.  Reset from SET_INTERFACE.
+	 */
+	if (!cdc_active(dev)) {
+		result = usb_ep_enable (dev->in_ep, dev->in);
+		if (result != 0) {
+			printf ("enable %s --> %d\n",
+				dev->in_ep->name, result);
+			goto done;
+		}
+
+		result = usb_ep_enable (dev->out_ep, dev->out);
+		if (result != 0) {
+			printf ("enable %s --> %d\n",
+				dev->out_ep->name, result);
+			goto done;
+		}
+	}
+
+done:
+	if (result == 0)
+		result = alloc_requests (dev, qlen (gadget), gfp_flags);
+
+	/* on error, disable any endpoints  */
+	if (result < 0) {
+		if (!subset_active(dev))
+			(void) usb_ep_disable (dev->status_ep);
+		dev->status = NULL;
+		(void) usb_ep_disable (dev->in_ep);
+		(void) usb_ep_disable (dev->out_ep);
+		dev->in = NULL;
+		dev->out = NULL;
+	}
+
+	/* caller is responsible for cleanup on error */
+	return result;
+}
+
+
+static void eth_reset_config (struct eth_dev *dev)
+{
+	if (dev->config == 0)
+		return;
+
+	/* disable endpoints, forcing (synchronous) completion of
+	 * pending i/o.  then free the requests.
+	 */
+
+	if (dev->in) {
+		usb_ep_disable (dev->in_ep);
+		if (dev->tx_req) {
+			usb_ep_free_request (dev->in_ep, dev->tx_req);
+			dev->tx_req=NULL;
+		}
+	}
+	if (dev->out) {
+		usb_ep_disable (dev->out_ep);
+		if (dev->rx_req) {
+			usb_ep_free_request (dev->in_ep, dev->rx_req);
+			dev->rx_req=NULL;
+		}
+	}
+	if (dev->status) {
+		usb_ep_disable (dev->status_ep);
+	}
+	dev->cdc_filter = 0;
+	dev->config = 0;
+}
+
+/* change our operational config.  must agree with the code
+ * that returns config descriptors, and altsetting code.
+ */
+static int eth_set_config (struct eth_dev *dev, unsigned number, gfp_t gfp_flags)
+{
+	int			result = 0;
+	struct usb_gadget	*gadget = dev->gadget;
+
+	if (gadget_is_sa1100 (gadget)
+			&& dev->config
+			&& dev->tx_qlen != 0) {
+		/* tx fifo is full, but we can't clear it...*/
+		INFO (dev, "can't change configurations\n");
+		return -ESPIPE;
+	}
+	eth_reset_config (dev);
+
+	switch (number) {
+	case DEV_CONFIG_VALUE:
+		result = set_ether_config (dev, gfp_flags);
+		break;
+	default:
+		result = -EINVAL;
+		/* FALL THROUGH */
+	case 0:
+		break;
+	}
+
+	if (result) {
+		if (number)
+			eth_reset_config (dev);
+		usb_gadget_vbus_draw(dev->gadget,
+				gadget_is_otg(dev->gadget) ? 8 : 100);
+	} else {
+		char *speed;
+		unsigned power;
+
+		power = 2 * eth_config.bMaxPower;
+		usb_gadget_vbus_draw(dev->gadget, power);
+
+		switch (gadget->speed) {
+		case USB_SPEED_FULL:	speed = "full"; break;
+#ifdef CONFIG_USB_GADGET_DUALSPEED
+		case USB_SPEED_HIGH:	speed = "high"; break;
+#endif
+		default:		speed = "?"; break;
+		}
+
+		dev->config = number;
+		INFO (dev, "%s speed config #%d: %d mA, %s, using %s\n",
+				speed, number, power, driver_desc,
+				(cdc_active(dev)? "CDC Ethernet"
+						: "CDC Ethernet Subset"));
+	}
+	return result;
+}
+
+/*-------------------------------------------------------------------------*/
+
+#ifdef	DEV_CONFIG_CDC
+
+/* The interrupt endpoint is used in CDC networking models (Ethernet, ATM)
+ * only to notify the host about link status changes (which we support) or
+ * report completion of some encapsulated command.  Since
+ * we want this CDC Ethernet code to be vendor-neutral, we don't use that
+ * command mechanism; and only one status request is ever queued.
+ */
+static void eth_status_complete (struct usb_ep *ep, struct usb_request *req)
+{
+	struct usb_cdc_notification	*event = req->buf;
+	int				value = req->status;
+	struct eth_dev			*dev = ep->driver_data;
+
+	/* issue the second notification if host reads the first */
+	if (event->bNotificationType == USB_CDC_NOTIFY_NETWORK_CONNECTION
+			&& value == 0) {
+		__le32	*data = req->buf + sizeof *event;
+
+		event->bmRequestType = 0xA1;
+		event->bNotificationType = USB_CDC_NOTIFY_SPEED_CHANGE;
+		event->wValue = __constant_cpu_to_le16 (0);
+		event->wIndex = __constant_cpu_to_le16 (1);
+		event->wLength = __constant_cpu_to_le16 (8);
+
+		/* SPEED_CHANGE data is up/down speeds in bits/sec */
+		data [0] = data [1] = cpu_to_le32 (BITRATE (dev->gadget));
+
+		req->length = STATUS_BYTECOUNT;
+		value = usb_ep_queue (ep, req, GFP_ATOMIC);
+		dprintf ("send SPEED_CHANGE --> %d\n", value);
+		if (value == 0)
+			return;
+	} else if (value != -ECONNRESET) {
+		dprintf("event %02x --> %d\n",
+			event->bNotificationType, value);
+		if (event->bNotificationType==
+				USB_CDC_NOTIFY_SPEED_CHANGE)
+		{
+			l_ethdev.network_started=1;
+			printf("USB network up!\n");
+		}
+	}
+	req->context = NULL;
+}
+
+static void issue_start_status (struct eth_dev *dev)
+{
+	struct usb_request		*req = dev->stat_req;
+	struct usb_cdc_notification	*event;
+	int				value;
+
+	/* flush old status
+	 *
+	 * FIXME ugly idiom, maybe we'd be better with just
+	 * a "cancel the whole queue" primitive since any
+	 * unlink-one primitive has way too many error modes.
+	 * here, we "know" toggle is already clear...
+	 *
+	 * FIXME iff req->context != null just dequeue it
+	 */
+	usb_ep_disable (dev->status_ep);
+	usb_ep_enable (dev->status_ep, dev->status);
+
+	/* 3.8.1 says to issue first NETWORK_CONNECTION, then
+	 * a SPEED_CHANGE.  could be useful in some configs.
+	 */
+	event = req->buf;
+	event->bmRequestType = 0xA1;
+	event->bNotificationType = USB_CDC_NOTIFY_NETWORK_CONNECTION;
+	event->wValue = __constant_cpu_to_le16 (1);	/* connected */
+	event->wIndex = __constant_cpu_to_le16 (1);
+	event->wLength = 0;
+
+	req->length = sizeof *event;
+	req->complete = eth_status_complete;
+	req->context = dev;
+
+	value = usb_ep_queue (dev->status_ep, req, GFP_ATOMIC);
+	if (value < 0)
+		printf ("status buf queue --> %d\n", value);
+}
+
+#endif
+
+/*-------------------------------------------------------------------------*/
+
+static void eth_setup_complete (struct usb_ep *ep, struct usb_request *req)
+{
+	if (req->status || req->actual != req->length)
+		dprintf  (/*(struct eth_dev *) ep->driver_data*/
+				"setup complete --> %d, %d/%d\n",
+				req->status, req->actual, req->length);
+}
+
+/*
+ * The setup() callback implements all the ep0 functionality that's not
+ * handled lower down.  CDC has a number of less-common features:
+ *
+ *  - two interfaces:  control, and ethernet data
+ *  - Ethernet data interface has two altsettings:  default, and active
+ *  - class-specific descriptors for the control interface
+ *  - class-specific control requests
+ */
+static int
+eth_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
+{
+	struct eth_dev		*dev = get_gadget_data (gadget);
+	struct usb_request	*req = dev->req;
+	int			value = -EOPNOTSUPP;
+	u16			wIndex = le16_to_cpu(ctrl->wIndex);
+	u16			wValue = le16_to_cpu(ctrl->wValue);
+	u16			wLength = le16_to_cpu(ctrl->wLength);
+
+	/* descriptors just go into the pre-allocated ep0 buffer,
+	 * while config change events may enable network traffic.
+	 */
+
+	dprintf("eth_setup:...\n");
+
+	req->complete = eth_setup_complete;
+	switch (ctrl->bRequest) {
+
+	case USB_REQ_GET_DESCRIPTOR:
+		if (ctrl->bRequestType != USB_DIR_IN)
+			break;
+		switch (wValue >> 8) {
+
+		case USB_DT_DEVICE:
+			value = min (wLength, (u16) sizeof device_desc);
+			memcpy (req->buf, &device_desc, value);
+			break;
+		case USB_DT_DEVICE_QUALIFIER:
+			if (!gadget_is_dualspeed(gadget))
+				break;
+			value = min (wLength, (u16) sizeof dev_qualifier);
+			memcpy (req->buf, &dev_qualifier, value);
+			break;
+
+		case USB_DT_OTHER_SPEED_CONFIG:
+			if (!gadget_is_dualspeed(gadget))
+				break;
+			/* FALLTHROUGH */
+		case USB_DT_CONFIG:
+			value = config_buf(gadget, req->buf,
+					wValue >> 8,
+					wValue & 0xff,
+					gadget_is_otg(gadget));
+			if (value >= 0)
+				value = min (wLength, (u16) value);
+			break;
+
+		case USB_DT_STRING:
+			value = usb_gadget_get_string (&stringtab,
+					wValue & 0xff, req->buf);
+
+			if (value >= 0)
+				value = min (wLength, (u16) value);
+
+			break;
+		}
+		break;
+
+	case USB_REQ_SET_CONFIGURATION:
+		if (ctrl->bRequestType != 0)
+			break;
+		if (gadget->a_hnp_support)
+			DEBUG (dev, "HNP available\n");
+		else if (gadget->a_alt_hnp_support)
+			DEBUG (dev, "HNP needs a different root port\n");
+		value = eth_set_config (dev, wValue, GFP_ATOMIC);
+		break;
+	case USB_REQ_GET_CONFIGURATION:
+		if (ctrl->bRequestType != USB_DIR_IN)
+			break;
+		*(u8 *)req->buf = dev->config;
+		value = min (wLength, (u16) 1);
+		break;
+
+	case USB_REQ_SET_INTERFACE:
+		if (ctrl->bRequestType != USB_RECIP_INTERFACE
+				|| !dev->config
+				|| wIndex > 1)
+			break;
+		if (!cdc_active(dev) && wIndex != 0)
+			break;
+
+		/* PXA hardware partially handles SET_INTERFACE;
+		 * we need to kluge around that interference.
+		 */
+		if (gadget_is_pxa (gadget)) {
+			value = eth_set_config (dev, DEV_CONFIG_VALUE,
+						GFP_ATOMIC);
+			goto done_set_intf;
+		}
+
+#ifdef DEV_CONFIG_CDC
+		switch (wIndex) {
+		case 0:		/* control/master intf */
+			if (wValue != 0)
+				break;
+			if (dev->status) {
+				usb_ep_disable (dev->status_ep);
+				usb_ep_enable (dev->status_ep, dev->status);
+			}
+			value = 0;
+			break;
+		case 1:		/* data intf */
+			if (wValue > 1)
+				break;
+			usb_ep_disable (dev->in_ep);
+			usb_ep_disable (dev->out_ep);
+
+			/* CDC requires the data transfers not be done from
+			 * the default interface setting ... also, setting
+			 * the non-default interface resets filters etc.
+			 */
+			if (wValue == 1) {
+				if (!cdc_active (dev))
+					break;
+				usb_ep_enable (dev->in_ep, dev->in);
+				usb_ep_enable (dev->out_ep, dev->out);
+				dev->cdc_filter = DEFAULT_FILTER;
+				if (dev->status)
+					issue_start_status (dev);
+			}
+
+			value = 0;
+			break;
+		}
+#else
+		/* FIXME this is wrong, as is the assumption that
+		 * all non-PXA hardware talks real CDC ...
+		 */
+		dev_warn (&gadget->dev, "set_interface ignored!\n");
+#endif /* DEV_CONFIG_CDC */
+
+done_set_intf:
+		break;
+	case USB_REQ_GET_INTERFACE:
+		if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE)
+				|| !dev->config
+				|| wIndex > 1)
+			break;
+		if (!(cdc_active(dev)) && wIndex != 0)
+			break;
+
+		/* for CDC, iff carrier is on, data interface is active. */
+		if (wIndex != 1)
+			*(u8 *)req->buf = 0;
+		else {
+			/* *(u8 *)req->buf = netif_carrier_ok (dev->net) ? 1 : 0; */
+			/* carrier always ok ...*/
+			*(u8 *)req->buf = 1 ;
+		}
+		value = min (wLength, (u16) 1);
+		break;
+
+#ifdef DEV_CONFIG_CDC
+	case USB_CDC_SET_ETHERNET_PACKET_FILTER:
+		/* see 6.2.30: no data, wIndex = interface,
+		 * wValue = packet filter bitmap
+		 */
+		if (ctrl->bRequestType != (USB_TYPE_CLASS|USB_RECIP_INTERFACE)
+				|| !cdc_active(dev)
+				|| wLength != 0
+				|| wIndex > 1)
+			break;
+		printf ("packet filter %02x\n", wValue);
+		dev->cdc_filter = wValue;
+		value = 0;
+		break;
+
+	/* and potentially:
+	 * case USB_CDC_SET_ETHERNET_MULTICAST_FILTERS:
+	 * case USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER:
+	 * case USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER:
+	 * case USB_CDC_GET_ETHERNET_STATISTIC:
+	 */
+
+#endif /* DEV_CONFIG_CDC */
+
+	default:
+		printf (
+			"unknown control req%02x.%02x v%04x i%04x l%d\n",
+			ctrl->bRequestType, ctrl->bRequest,
+			wValue, wIndex, wLength);
+	}
+
+	/* respond with data transfer before status phase? */
+	if (value >= 0) {
+		dprintf("respond with data transfer before status phase\n");
+		req->length = value;
+		req->zero = value < wLength
+				&& (value % gadget->ep0->maxpacket) == 0;
+		value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
+		if (value < 0) {
+			DEBUG (dev, "ep_queue --> %d\n", value);
+			req->status = 0;
+			eth_setup_complete (gadget->ep0, req);
+		}
+	}
+
+	/* host either stalls (value < 0) or reports success */
+	return value;
+}
+
+
+/*-------------------------------------------------------------------------*/
+
+static void rx_complete (struct usb_ep *ep, struct usb_request *req);
+
+static int rx_submit ( struct eth_dev *dev, struct usb_request *req, \
+				gfp_t gfp_flags)
+{
+	int			retval = -ENOMEM;
+	size_t			size;
+
+	/* Padding up to RX_EXTRA handles minor disagreements with host.
+	 * Normally we use the USB "terminate on short read" convention;
+	 * so allow up to (N*maxpacket), since that memory is normally
+	 * already allocated.  Some hardware doesn't deal well with short
+	 * reads (e.g. DMA must be N*maxpacket), so for now don't trim a
+	 * byte off the end (to force hardware errors on overflow).
+	 */
+
+	dprintf("%s\n", __func__);
+
+	size = (ETHER_HDR_SIZE + dev->mtu + RX_EXTRA);
+	size += dev->out_ep->maxpacket - 1;
+	size -= size % dev->out_ep->maxpacket;
+
+
+	/* Some platforms perform better when IP packets are aligned,
+	 * but on at least one, checksumming fails otherwise.
+	 */
+
+	req->buf = (u8 *) NetRxPackets[0];
+	req->length = size;
+	req->complete = rx_complete;
+
+	retval = usb_ep_queue (dev->out_ep, req, gfp_flags);
+
+	if (retval) {
+		dprintf ("rx submit --> %d\n", retval);
+	}
+	return retval;
+}
+
+
+static void rx_complete (struct usb_ep *ep, struct usb_request *req)
+{
+	struct eth_dev	*dev = ep->driver_data;
+
+	dprintf("%s\n", __func__);
+	dprintf("rx status %d\n", req->status);
+
+	packet_received=1;
+
+	if (req)
+		dev->rx_req=req;
+}
+
+
+static int alloc_requests (struct eth_dev *dev, unsigned n, gfp_t gfp_flags)
+{
+
+	dev->tx_req = usb_ep_alloc_request (dev->in_ep, 0);
+
+	if (!dev->tx_req)
+		goto fail;
+
+	dev->rx_req = usb_ep_alloc_request (dev->out_ep, 0);
+
+	if (!dev->rx_req)
+		goto fail;
+
+	return 0;
+
+fail:
+	DEBUG (dev, "can't alloc requests\n");
+	return -1;
+}
+
+
+static void tx_complete (struct usb_ep *ep, struct usb_request *req)
+{
+	dprintf("%s, status: %s\n", __func__,(req->status) ? "failed":"ok");
+	packet_sent=1;
+}
+
+static inline int eth_is_promisc (struct eth_dev *dev)
+{
+	/* no filters for the CDC subset; always promisc */
+	if (subset_active (dev))
+		return 1;
+	return dev->cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS;
+}
+
+#if 0
+static int eth_start_xmit (struct sk_buff *skb, struct net_device *net)
+{
+	struct eth_dev		*dev = netdev_priv(net);
+	int			length = skb->len;
+	int			retval;
+	struct usb_request	*req = NULL;
+	unsigned long		flags;
+
+	/* apply outgoing CDC or RNDIS filters */
+	if (!eth_is_promisc (dev)) {
+		u8		*dest = skb->data;
+
+		if (is_multicast_ether_addr(dest)) {
+			u16	type;
+
+			/* ignores USB_CDC_PACKET_TYPE_MULTICAST and host
+			 * SET_ETHERNET_MULTICAST_FILTERS requests
+			 */
+			if (is_broadcast_ether_addr(dest))
+				type = USB_CDC_PACKET_TYPE_BROADCAST;
+			else
+				type = USB_CDC_PACKET_TYPE_ALL_MULTICAST;
+			if (!(dev->cdc_filter & type)) {
+				dev_kfree_skb_any (skb);
+				return 0;
+			}
+		}
+		/* ignores USB_CDC_PACKET_TYPE_DIRECTED */
+	}
+
+	spin_lock_irqsave(&dev->req_lock, flags);
+	/*
+	 * this freelist can be empty if an interrupt triggered disconnect()
+	 * and reconfigured the gadget (shutting down this queue) after the
+	 * network stack decided to xmit but before we got the spinlock.
+	 */
+	if (list_empty(&dev->tx_reqs)) {
+		spin_unlock_irqrestore(&dev->req_lock, flags);
+		return 1;
+	}
+
+	req = container_of (dev->tx_reqs.next, struct usb_request, list);
+	list_del (&req->list);
+
+	/* temporarily stop TX queue when the freelist empties */
+	if (list_empty (&dev->tx_reqs))
+		netif_stop_queue (net);
+	spin_unlock_irqrestore(&dev->req_lock, flags);
+
+	/* no buffer copies needed, unless the network stack did it
+	 * or the hardware can't use skb buffers.
+	 * or there's not enough space for any RNDIS headers we need
+	 */
+	if (rndis_active(dev)) {
+		struct sk_buff	*skb_rndis;
+
+		skb_rndis = skb_realloc_headroom (skb,
+				sizeof (struct rndis_packet_msg_type));
+		if (!skb_rndis)
+			goto drop;
+
+		dev_kfree_skb_any (skb);
+		skb = skb_rndis;
+		rndis_add_hdr (skb);
+		length = skb->len;
+	}
+	req->buf = skb->data;
+	req->context = skb;
+	req->complete = tx_complete;
+
+	/* use zlp framing on tx for strict CDC-Ether conformance,
+	 * though any robust network rx path ignores extra padding.
+	 * and some hardware doesn't like to write zlps.
+	 */
+	req->zero = 1;
+	if (!dev->zlp && (length % dev->in_ep->maxpacket) == 0)
+		length++;
+
+	req->length = length;
+
+	/* throttle highspeed IRQ rate back slightly */
+	if (gadget_is_dualspeed(dev->gadget))
+		req->no_interrupt = (dev->gadget->speed == USB_SPEED_HIGH)
+			? ((atomic_read(&dev->tx_qlen) % qmult) != 0)
+			: 0;
+
+	retval = usb_ep_queue (dev->in_ep, req, GFP_ATOMIC);
+	switch (retval) {
+	default:
+		DEBUG (dev, "tx queue err %d\n", retval);
+		break;
+	case 0:
+		net->trans_start = jiffies;
+		atomic_inc (&dev->tx_qlen);
+	}
+
+	if (retval) {
+drop:
+		dev->stats.tx_dropped++;
+		dev_kfree_skb_any (skb);
+		spin_lock_irqsave(&dev->req_lock, flags);
+		if (list_empty (&dev->tx_reqs))
+			netif_start_queue (net);
+		list_add (&req->list, &dev->tx_reqs);
+		spin_unlock_irqrestore(&dev->req_lock, flags);
+	}
+	return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+#endif
+
+static void eth_unbind (struct usb_gadget *gadget)
+{
+	struct eth_dev *dev = get_gadget_data (gadget);
+
+	printf("eth_unbind:...\n");
+
+	if (dev->stat_req) {
+		usb_ep_free_request (dev->status_ep, dev->stat_req);
+		dev->stat_req = NULL;
+	}
+
+	if (dev->tx_req) {
+		usb_ep_free_request (dev->in_ep, dev->tx_req);
+		dev->tx_req=NULL;
+	}
+
+	if (dev->rx_req) {
+		usb_ep_free_request (dev->in_ep, dev->rx_req);
+		dev->rx_req=NULL;
+	}
+
+/*	unregister_netdev (dev->net);*/
+/*	free_netdev(dev->net);*/
+
+	set_gadget_data (gadget, NULL);
+}
+
+static void eth_disconnect (struct usb_gadget *gadget)
+{
+	eth_reset_config (get_gadget_data (gadget));
+}
+
+static void eth_suspend (struct usb_gadget *gadget)
+{
+	/* Not used */
+}
+
+static void eth_resume (struct usb_gadget *gadget)
+{
+	/* Not used */
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int is_eth_addr_valid(char *str)
+{
+	if (strlen(str) == 17) {
+		int i;
+		char *p, *q;
+		uchar ea[6];
+
+		/* see if it looks like an ethernet address */
+
+		p = str;
+
+		for (i = 0; i < 6; i++) {
+			char term = (i == 5 ? '\0' : ':');
+
+			ea[i] = simple_strtol(p, &q, 16);
+
+			if ((q - p) != 2 || *q++ != term)
+				break;
+
+			p = q;
+		}
+
+		if (i == 6) /* it looks ok */
+			return 1;
+	}
+	return 0;
+}
+
+static u8 nibble (unsigned char c)
+{
+	if (likely (isdigit (c)))
+		return c - '0';
+	c = toupper (c);
+	if (likely (isxdigit (c)))
+		return 10 + c - 'A';
+	return 0;
+}
+
+static int get_ether_addr(const char *str, u8 *dev_addr)
+{
+	if (str) {
+		unsigned	i;
+
+		for (i = 0; i < 6; i++) {
+			unsigned char num;
+
+			if((*str == '.') || (*str == ':'))
+				str++;
+			num = nibble(*str++) << 4;
+			num |= (nibble(*str++));
+			dev_addr [i] = num;
+		}
+		if (is_valid_ether_addr (dev_addr))
+			return 0;
+	}
+	return 1;
+}
+
+static int eth_bind(struct usb_gadget *gadget)
+{
+	struct eth_dev		*dev = &l_ethdev;
+	u8			cdc = 1, zlp = 1;
+	struct usb_ep		*in_ep, *out_ep, *status_ep = NULL;
+	int			gcnum;
+	u8 			tmp[7];
+
+	/* these flags are only ever cleared; compiler take note */
+#ifndef	DEV_CONFIG_CDC
+	cdc = 0;
+#endif
+	/* Because most host side USB stacks handle CDC Ethernet, that
+	 * standard protocol is _strongly_ preferred for interop purposes.
+	 * (By everyone except Microsoft.)
+	 */
+	if (gadget_is_pxa (gadget)) {
+		/* pxa doesn't support altsettings */
+		cdc = 0;
+	} else if (gadget_is_musbhdrc(gadget)) {
+		/* reduce tx dma overhead by avoiding special cases */
+		zlp = 0;
+	} else if (gadget_is_sh(gadget)) {
+		/* sh doesn't support multiple interfaces or configs */
+		cdc = 0;
+	} else if (gadget_is_sa1100 (gadget)) {
+		/* hardware can't write zlps */
+		zlp = 0;
+		/* sa1100 CAN do CDC, without status endpoint ... we use
+		 * non-CDC to be compatible with ARM Linux-2.4 "usb-eth".
+		 */
+		cdc = 0;
+	}
+
+	gcnum = usb_gadget_controller_number (gadget);
+	if (gcnum >= 0)
+		device_desc.bcdDevice = cpu_to_le16 (0x0300 + gcnum);
+	else {
+		/* can't assume CDC works.  don't want to default to
+		 * anything less functional on CDC-capable hardware,
+		 * so we fail in this case.
+		 */
+		dev_err (&gadget->dev,
+			"controller '%s' not recognized\n",
+			gadget->name);
+		return -ENODEV;
+	}
+
+	/* CDC subset ... recognized by Linux since 2.4.10, but Windows
+	 * drivers aren't widely available.  (That may be improved by
+	 * supporting one submode of the "SAFE" variant of MDLM.)
+	 */
+	if (!cdc) {
+		device_desc.idVendor =
+			__constant_cpu_to_le16(SIMPLE_VENDOR_NUM);
+		device_desc.idProduct =
+			__constant_cpu_to_le16(SIMPLE_PRODUCT_NUM);
+	}
+
+	/* support optional vendor/distro customization */
+#if defined(CONFIG_USB_CDC_VENDOR_ID) && defined(CONFIG_USB_CDC_PRODUCT_ID)
+	device_desc.idVendor = cpu_to_le16(CONFIG_USB_CDC_VENDOR_ID);
+	device_desc.idProduct = cpu_to_le16(CONFIG_USB_CDC_PRODUCT_ID);
+#endif
+	if (bcdDevice)
+		device_desc.bcdDevice = cpu_to_le16(bcdDevice);
+	if (iManufacturer)
+		strcpy (manufacturer, iManufacturer);
+	if (iProduct)
+		strcpy (product_desc, iProduct);
+	if (iSerialNumber) {
+		device_desc.iSerialNumber = STRING_SERIALNUMBER,
+		strcpy(serial_number, iSerialNumber);
+	}
+
+	/* all we really need is bulk IN/OUT */
+	usb_ep_autoconfig_reset (gadget);
+	in_ep = usb_ep_autoconfig (gadget, &fs_source_desc);
+	if (!in_ep) {
+autoconf_fail:
+		dev_err (&gadget->dev,
+			"can't autoconfigure on %s\n",
+			gadget->name);
+		return -ENODEV;
+	}
+	in_ep->driver_data = in_ep;	/* claim */
+
+	out_ep = usb_ep_autoconfig (gadget, &fs_sink_desc);
+	if (!out_ep)
+		goto autoconf_fail;
+	out_ep->driver_data = out_ep;	/* claim */
+
+#if defined(DEV_CONFIG_CDC)
+	/* CDC Ethernet control interface doesn't require a status endpoint.
+	 * Since some hosts expect one, try to allocate one anyway.
+	 */
+	if (cdc) {
+		status_ep = usb_ep_autoconfig (gadget, &fs_status_desc);
+		if (status_ep) {
+			status_ep->driver_data = status_ep;	/* claim */
+		} else if (cdc) {
+			control_intf.bNumEndpoints = 0;
+			/* FIXME remove endpoint from descriptor list */
+		}
+	}
+#endif
+
+	/* one config:  cdc, else minimal subset */
+	if (!cdc) {
+		eth_config.bNumInterfaces = 1;
+		eth_config.iConfiguration = STRING_SUBSET;
+
+		/* use functions to set these up, in case we're built to work
+		 * with multiple controllers and must override CDC Ethernet.
+		 */
+		fs_subset_descriptors();
+		hs_subset_descriptors();
+	}
+
+	device_desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
+	usb_gadget_set_selfpowered (gadget);
+
+	if (gadget_is_dualspeed(gadget)) {
+		if (!cdc)
+			dev_qualifier.bDeviceClass = USB_CLASS_VENDOR_SPEC;
+
+		/* assumes ep0 uses the same value for both speeds ... */
+		dev_qualifier.bMaxPacketSize0 = device_desc.bMaxPacketSize0;
+
+		/* and that all endpoints are dual-speed */
+		hs_source_desc.bEndpointAddress =
+				fs_source_desc.bEndpointAddress;
+		hs_sink_desc.bEndpointAddress =
+				fs_sink_desc.bEndpointAddress;
+#if defined(DEV_CONFIG_CDC)
+		if (status_ep)
+			hs_status_desc.bEndpointAddress =
+					fs_status_desc.bEndpointAddress;
+#endif
+	}
+
+	if (gadget_is_otg(gadget)) {
+		otg_descriptor.bmAttributes |= USB_OTG_HNP,
+		eth_config.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
+		eth_config.bMaxPower = 4;
+	}
+
+	dev->net = &l_netdev;
+	strcpy (dev->net->name, USB_NET_NAME);
+
+	dev->cdc = cdc;
+	dev->zlp = zlp;
+
+	dev->in_ep = in_ep;
+	dev->out_ep = out_ep;
+	dev->status_ep = status_ep;
+
+	/* Module params for these addresses should come from ID proms.
+	 * The host side address is used with CDC, and commonly
+	 * ends up in a persistent config database.  It's not clear if
+	 * host side code for the SAFE thing cares -- its original BLAN
+	 * thing didn't, Sharp never assigned those addresses on Zaurii.
+	 */
+	get_ether_addr(dev_addr, dev->net->enetaddr);
+
+	memset(tmp, 0, sizeof(tmp));
+	memcpy(tmp, dev->net->enetaddr, sizeof(dev->net->enetaddr));
+
+	get_ether_addr(host_addr, dev->host_mac);
+
+	sprintf (ethaddr, "%02X%02X%02X%02X%02X%02X",
+		dev->host_mac [0], dev->host_mac [1],
+			dev->host_mac [2], dev->host_mac [3],
+			dev->host_mac [4], dev->host_mac [5]);
+
+	INFO (dev, "using %s, OUT %s IN %s%s%s\n", gadget->name,
+		out_ep->name, in_ep->name,
+		status_ep ? " STATUS " : "",
+		status_ep ? status_ep->name : ""
+		);
+	INFO (dev, "MAC %02x:%02x:%02x:%02x:%02x:%02x\n",
+		dev->net->enetaddr [0], dev->net->enetaddr [1],
+		dev->net->enetaddr [2], dev->net->enetaddr [3],
+		dev->net->enetaddr [4], dev->net->enetaddr [5]);
+
+	if (cdc) {
+		INFO (dev, "HOST MAC %02x:%02x:%02x:%02x:%02x:%02x\n",
+			dev->host_mac [0], dev->host_mac [1],
+			dev->host_mac [2], dev->host_mac [3],
+			dev->host_mac [4], dev->host_mac [5]);
+	}
+
+	/* use PKTSIZE (or aligned... from u-boot) and set
+	 * wMaxSegmentSize accordingly*/
+	dev->mtu = PKTSIZE_ALIGN; /* RNDIS does not like this, only 1514, TODO*/
+
+	/* preallocate control message data and buffer */
+	dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
+	if (!dev->req)
+		goto fail;
+	dev->req->buf = control_req;
+	dev->req->complete = eth_setup_complete;
+
+	/* ... and maybe likewise for status transfer */
+#if defined(DEV_CONFIG_CDC)
+	if (dev->status_ep) {
+		dev->stat_req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
+		dev->stat_req->buf = status_req;
+		if (!dev->stat_req) {
+			dev->stat_req->buf=NULL;
+			usb_ep_free_request (gadget->ep0, dev->req);
+
+			goto fail;
+		}
+		dev->stat_req->context = NULL;
+	}
+#endif
+
+	/* finish hookup to lower layer ... */
+	dev->gadget = gadget;
+	set_gadget_data (gadget, dev);
+	gadget->ep0->driver_data = dev;
+
+	/* two kinds of host-initiated state changes:
+	 *  - iff DATA transfer is active, carrier is "on"
+	 *  - tx queueing enabled if open *and* carrier is "on"
+	 */
+	return 0;
+
+fail:
+	dev_dbg(&gadget->dev, "register_netdev failed\n");
+	eth_unbind (gadget);
+	return -ENOMEM;
+}
+
+static int usb_eth_init(struct eth_device* netdev, bd_t* bd)
+{
+	struct eth_dev *dev=&l_ethdev;
+	struct usb_gadget *gadget;
+	unsigned long ts;
+	unsigned long timeout = USB_CONNECT_TIMEOUT;
+
+	if (!netdev) {
+		printf("ERROR: received NULL ptr\n");
+		goto fail;
+	}
+
+	dev->network_started = 0;
+	dev->tx_req = NULL;
+	dev->rx_req = NULL;
+
+	packet_received = 0;
+	packet_sent = 0;
+
+	gadget = dev->gadget;
+	usb_gadget_connect(gadget);
+
+	if (getenv("cdc_connect_timeout"))
+		timeout = simple_strtoul(getenv("cdc_connect_timeout"),
+						NULL, 10) * CONFIG_SYS_HZ;
+	ts = get_timer(0);
+	while (!l_ethdev.network_started)
+	{
+		/* Handle control-c and timeouts */
+		if (ctrlc() || (get_timer(ts) > timeout)) {
+			printf("The remote end did not respond in time.\n");
+			goto fail;
+		}
+		usb_gadget_handle_interrupts();
+	}
+
+	rx_submit (dev, dev->rx_req, 0);
+	return 0;
+fail:
+	return -1;
+}
+
+static int usb_eth_send(struct eth_device* netdev, volatile void* packet, int length)
+{
+	int			retval;
+	struct usb_request	*req = NULL;
+
+	struct eth_dev *dev = &l_ethdev;
+	dprintf("%s:...\n",__func__);
+
+	req = dev->tx_req;
+
+	req->buf = (void *)packet;
+	req->context = NULL;
+	req->complete = tx_complete;
+
+	/* use zlp framing on tx for strict CDC-Ether conformance,
+	 * though any robust network rx path ignores extra padding.
+	 * and some hardware doesn't like to write zlps.
+	 */
+	req->zero = 1;
+	if (!dev->zlp && (length % dev->in_ep->maxpacket) == 0)
+		length++;
+
+	req->length = length;
+#if 0
+	/* throttle highspeed IRQ rate back slightly */
+	if (gadget_is_dualspeed(dev->gadget))
+		req->no_interrupt = (dev->gadget->speed == USB_SPEED_HIGH)
+			? ((dev->tx_qlen % qmult) != 0) : 0;
+#endif
+	dev->tx_qlen=1;
+
+	retval = usb_ep_queue (dev->in_ep, req, GFP_ATOMIC);
+
+	if (!retval)
+		dprintf("%s: packet queued\n",__func__);
+	while(!packet_sent)
+	{
+		packet_sent=0;
+	}
+
+	return 0;
+}
+
+static int usb_eth_recv(struct eth_device* netdev)
+{
+	struct eth_dev *dev = &l_ethdev;
+
+	usb_gadget_handle_interrupts();
+
+	if (packet_received)
+	{
+		dprintf("%s: packet received \n",__func__);
+		if (dev->rx_req)
+		{
+			NetReceive(NetRxPackets[0],dev->rx_req->length);
+			packet_received=0;
+
+			if (dev->rx_req)
+				rx_submit (dev, dev->rx_req, 0);
+		}
+		else printf("dev->rx_req invalid\n");
+	}
+	return 0;
+}
+
+void usb_eth_halt(struct eth_device* netdev)
+{
+	struct eth_dev *dev =&l_ethdev;
+
+	if (!netdev)
+	{
+		printf("ERROR: received NULL ptr\n");
+		return;
+	}
+
+	usb_gadget_disconnect(dev->gadget);
+}
+
+static struct usb_gadget_driver eth_driver = {
+	.speed		= DEVSPEED,
+
+	.bind		= eth_bind,
+	.unbind		= eth_unbind,
+
+	.setup		= eth_setup,
+	.disconnect	= eth_disconnect,
+
+	.suspend	= eth_suspend,
+	.resume		= eth_resume,
+};
+
+int usb_eth_initialize(bd_t *bi)
+{
+	int status = 0;
+	struct eth_device *netdev=&l_netdev;
+
+	sprintf(netdev->name,"usb_ether");
+
+	netdev->init = usb_eth_init;
+	netdev->send = usb_eth_send;
+	netdev->recv = usb_eth_recv;
+	netdev->halt = usb_eth_halt;
+
+#ifdef CONFIG_MCAST_TFTP
+  #error not supported
+#endif
+	/* Configure default mac-addresses for the USB ethernet device */
+#ifdef CONFIG_USBNET_DEV_ADDR
+	strncpy(dev_addr, CONFIG_USBNET_DEV_ADDR, sizeof(dev_addr));
+#endif
+#ifdef CONFIG_USBNET_HOST_ADDR
+	strncpy(host_addr, CONFIG_USBNET_HOST_ADDR, sizeof(host_addr));
+#endif
+	/* Check if the user overruled the MAC addresses */
+	if (getenv("usbnet_devaddr"))
+		strncpy(dev_addr, getenv("usbnet_devaddr"),
+			sizeof(dev_addr));
+
+	if (getenv("usbnet_hostaddr"))
+		strncpy(host_addr, getenv("usbnet_hostaddr"),
+			sizeof(host_addr));
+
+	/* Make sure both strings are terminated */
+	dev_addr[sizeof(dev_addr)-1] = '\0';
+	host_addr[sizeof(host_addr)-1] = '\0';
+
+	if (!is_eth_addr_valid(dev_addr)) {
+		printf("ERROR: Need valid 'usbnet_devaddr' to be set\n");
+		status = -1;
+	}
+	if (!is_eth_addr_valid(host_addr)) {
+		printf("ERROR: Need valid 'usbnet_hostaddr' to be set\n");
+		status = -1;
+	}
+	if (status)
+		goto fail;
+
+	status = usb_gadget_register_driver(&eth_driver);
+	if (status < 0)
+		goto fail;
+
+	eth_register(netdev);
+	return 0;
+
+fail:
+	printf("%s failed\n", __func__ );
+	return status;
+}
+
diff --git a/drivers/usb/gadget/gadget_chips.h b/drivers/usb/gadget/gadget_chips.h
new file mode 100644
index 0000000000..480bc87698
--- /dev/null
+++ b/drivers/usb/gadget/gadget_chips.h
@@ -0,0 +1,219 @@
+/*
+ * USB device controllers have lots of quirks.  Use these macros in
+ * gadget drivers or other code that needs to deal with them, and which
+ * autoconfigures instead of using early binding to the hardware.
+ *
+ * This SHOULD eventually work like the ARM mach_is_*() stuff, driven by
+ * some config file that gets updated as new hardware is supported.
+ * (And avoiding all runtime comparisons in typical one-choice configs!)
+ *
+ * NOTE:  some of these controller drivers may not be available yet.
+ * Some are available on 2.4 kernels; several are available, but not
+ * yet pushed in the 2.6 mainline tree.
+ *
+ * Ported to U-boot by: Thomas Smits <ts.smits@gmail.com> and
+ *                      Remy Bohmer <linux@bohmer.net>
+ */
+#ifdef CONFIG_USB_GADGET_NET2280
+#define	gadget_is_net2280(g)	!strcmp("net2280", (g)->name)
+#else
+#define	gadget_is_net2280(g)	0
+#endif
+
+#ifdef CONFIG_USB_GADGET_AMD5536UDC
+#define	gadget_is_amd5536udc(g)	!strcmp("amd5536udc", (g)->name)
+#else
+#define	gadget_is_amd5536udc(g)	0
+#endif
+
+#ifdef CONFIG_USB_GADGET_DUMMY_HCD
+#define	gadget_is_dummy(g)	!strcmp("dummy_udc", (g)->name)
+#else
+#define	gadget_is_dummy(g)	0
+#endif
+
+#ifdef CONFIG_USB_GADGET_PXA2XX
+#define	gadget_is_pxa(g)	!strcmp("pxa2xx_udc", (g)->name)
+#else
+#define	gadget_is_pxa(g)	0
+#endif
+
+#ifdef CONFIG_USB_GADGET_GOKU
+#define	gadget_is_goku(g)	!strcmp("goku_udc", (g)->name)
+#else
+#define	gadget_is_goku(g)	0
+#endif
+
+/* SH3 UDC -- not yet ported 2.4 --> 2.6 */
+#ifdef CONFIG_USB_GADGET_SUPERH
+#define	gadget_is_sh(g)		!strcmp("sh_udc", (g)->name)
+#else
+#define	gadget_is_sh(g)		0
+#endif
+
+/* not yet stable on 2.6 (would help "original Zaurus") */
+#ifdef CONFIG_USB_GADGET_SA1100
+#define	gadget_is_sa1100(g)	!strcmp("sa1100_udc", (g)->name)
+#else
+#define	gadget_is_sa1100(g)	0
+#endif
+
+#ifdef CONFIG_USB_GADGET_LH7A40X
+#define	gadget_is_lh7a40x(g)	!strcmp("lh7a40x_udc", (g)->name)
+#else
+#define	gadget_is_lh7a40x(g)	0
+#endif
+
+/* handhelds.org tree (?) */
+#ifdef CONFIG_USB_GADGET_MQ11XX
+#define	gadget_is_mq11xx(g)	!strcmp("mq11xx_udc", (g)->name)
+#else
+#define	gadget_is_mq11xx(g)	0
+#endif
+
+#ifdef CONFIG_USB_GADGET_OMAP
+#define	gadget_is_omap(g)	!strcmp("omap_udc", (g)->name)
+#else
+#define	gadget_is_omap(g)	0
+#endif
+
+/* not yet ported 2.4 --> 2.6 */
+#ifdef CONFIG_USB_GADGET_N9604
+#define	gadget_is_n9604(g)	!strcmp("n9604_udc", (g)->name)
+#else
+#define	gadget_is_n9604(g)	0
+#endif
+
+/* various unstable versions available */
+#ifdef CONFIG_USB_GADGET_PXA27X
+#define	gadget_is_pxa27x(g)	!strcmp("pxa27x_udc", (g)->name)
+#else
+#define	gadget_is_pxa27x(g)	0
+#endif
+
+#ifdef CONFIG_USB_GADGET_ATMEL_USBA
+#define gadget_is_atmel_usba(g)	!strcmp("atmel_usba_udc", (g)->name)
+#else
+#define gadget_is_atmel_usba(g)	0
+#endif
+
+#ifdef CONFIG_USB_GADGET_S3C2410
+#define gadget_is_s3c2410(g)    !strcmp("s3c2410_udc", (g)->name)
+#else
+#define gadget_is_s3c2410(g)    0
+#endif
+
+#ifdef CONFIG_USB_GADGET_AT91
+#define gadget_is_at91(g)	!strcmp("at91_udc", (g)->name)
+#else
+#define gadget_is_at91(g)	0
+#endif
+
+/* status unclear */
+#ifdef CONFIG_USB_GADGET_IMX
+#define gadget_is_imx(g)	!strcmp("imx_udc", (g)->name)
+#else
+#define gadget_is_imx(g)	0
+#endif
+
+#ifdef CONFIG_USB_GADGET_FSL_USB2
+#define gadget_is_fsl_usb2(g)	!strcmp("fsl-usb2-udc", (g)->name)
+#else
+#define gadget_is_fsl_usb2(g)	0
+#endif
+
+/* Mentor high speed function controller */
+/* from Montavista kernel (?) */
+#ifdef CONFIG_USB_GADGET_MUSBHSFC
+#define gadget_is_musbhsfc(g)	!strcmp("musbhsfc_udc", (g)->name)
+#else
+#define gadget_is_musbhsfc(g)	0
+#endif
+
+/* Mentor high speed "dual role" controller, in peripheral role */
+#ifdef CONFIG_USB_GADGET_MUSB_HDRC
+#define gadget_is_musbhdrc(g)	!strcmp("musb_hdrc", (g)->name)
+#else
+#define gadget_is_musbhdrc(g)	0
+#endif
+
+/* from Montavista kernel (?) */
+#ifdef CONFIG_USB_GADGET_MPC8272
+#define gadget_is_mpc8272(g)	!strcmp("mpc8272_udc", (g)->name)
+#else
+#define gadget_is_mpc8272(g)	0
+#endif
+
+#ifdef CONFIG_USB_GADGET_M66592
+#define	gadget_is_m66592(g)	!strcmp("m66592_udc", (g)->name)
+#else
+#define	gadget_is_m66592(g)	0
+#endif
+
+
+// CONFIG_USB_GADGET_SX2
+// CONFIG_USB_GADGET_AU1X00
+// ...
+
+
+/**
+ * usb_gadget_controller_number - support bcdDevice id convention
+ * @gadget: the controller being driven
+ *
+ * Return a 2-digit BCD value associated with the peripheral controller,
+ * suitable for use as part of a bcdDevice value, or a negative error code.
+ *
+ * NOTE:  this convention is purely optional, and has no meaning in terms of
+ * any USB specification.  If you want to use a different convention in your
+ * gadget driver firmware -- maybe a more formal revision ID -- feel free.
+ *
+ * Hosts see these bcdDevice numbers, and are allowed (but not encouraged!)
+ * to change their behavior accordingly.  For example it might help avoiding
+ * some chip bug.
+ */
+static inline int usb_gadget_controller_number(struct usb_gadget *gadget)
+{
+	if (gadget_is_net2280(gadget))
+		return 0x01;
+	else if (gadget_is_dummy(gadget))
+		return 0x02;
+	else if (gadget_is_pxa(gadget))
+		return 0x03;
+	else if (gadget_is_sh(gadget))
+		return 0x04;
+	else if (gadget_is_sa1100(gadget))
+		return 0x05;
+	else if (gadget_is_goku(gadget))
+		return 0x06;
+	else if (gadget_is_mq11xx(gadget))
+		return 0x07;
+	else if (gadget_is_omap(gadget))
+		return 0x08;
+	else if (gadget_is_lh7a40x(gadget))
+		return 0x09;
+	else if (gadget_is_n9604(gadget))
+		return 0x10;
+	else if (gadget_is_pxa27x(gadget))
+		return 0x11;
+	else if (gadget_is_s3c2410(gadget))
+		return 0x12;
+	else if (gadget_is_at91(gadget))
+		return 0x13;
+	else if (gadget_is_imx(gadget))
+		return 0x14;
+	else if (gadget_is_musbhsfc(gadget))
+		return 0x15;
+	else if (gadget_is_musbhdrc(gadget))
+		return 0x16;
+	else if (gadget_is_mpc8272(gadget))
+		return 0x17;
+	else if (gadget_is_atmel_usba(gadget))
+		return 0x18;
+	else if (gadget_is_fsl_usb2(gadget))
+		return 0x19;
+	else if (gadget_is_amd5536udc(gadget))
+		return 0x20;
+	else if (gadget_is_m66592(gadget))
+		return 0x21;
+	return -ENOENT;
+}
diff --git a/drivers/usb/gadget/usbstring.c b/drivers/usb/gadget/usbstring.c
new file mode 100644
index 0000000000..168f75f7ad
--- /dev/null
+++ b/drivers/usb/gadget/usbstring.c
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2003 David Brownell
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * Ported to U-boot by: Thomas Smits <ts.smits@gmail.com> and
+ *                      Remy Bohmer <linux@bohmer.net>
+ */
+
+#include <common.h>
+#include <asm/errno.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+
+#include <asm/unaligned.h>
+
+
+static int utf8_to_utf16le(const char *s, __le16 *cp, unsigned len)
+{
+	int	count = 0;
+	u8	c;
+	u16	uchar;
+
+	/* this insists on correct encodings, though not minimal ones.
+	 * BUT it currently rejects legit 4-byte UTF-8 code points,
+	 * which need surrogate pairs.  (Unicode 3.1 can use them.)
+	 */
+	while (len != 0 && (c = (u8) *s++) != 0) {
+		if ((c & 0x80)) {
+			// 2-byte sequence:
+			// 00000yyyyyxxxxxx = 110yyyyy 10xxxxxx
+			if ((c & 0xe0) == 0xc0) {
+				uchar = (c & 0x1f) << 6;
+
+				c = (u8) *s++;
+				if ((c & 0xc0) != 0x80)
+					goto fail;
+				c &= 0x3f;
+				uchar |= c;
+
+			// 3-byte sequence (most CJKV characters):
+			// zzzzyyyyyyxxxxxx = 1110zzzz 10yyyyyy 10xxxxxx
+			} else if ((c & 0xf0) == 0xe0) {
+				uchar = (c & 0x0f) << 12;
+
+				c = (u8) *s++;
+				if ((c & 0xc0) != 0x80)
+					goto fail;
+				c &= 0x3f;
+				uchar |= c << 6;
+
+				c = (u8) *s++;
+				if ((c & 0xc0) != 0x80)
+					goto fail;
+				c &= 0x3f;
+				uchar |= c;
+
+				/* no bogus surrogates */
+				if (0xd800 <= uchar && uchar <= 0xdfff)
+					goto fail;
+
+			// 4-byte sequence (surrogate pairs, currently rare):
+			// 11101110wwwwzzzzyy + 110111yyyyxxxxxx
+			//     = 11110uuu 10uuzzzz 10yyyyyy 10xxxxxx
+			// (uuuuu = wwww + 1)
+			// FIXME accept the surrogate code points (only)
+
+			} else
+				goto fail;
+		} else
+			uchar = c;
+		put_unaligned_le16(uchar, cp++);
+		count++;
+		len--;
+	}
+	return count;
+fail:
+	return -1;
+}
+
+
+/**
+ * usb_gadget_get_string - fill out a string descriptor
+ * @table: of c strings encoded using UTF-8
+ * @id: string id, from low byte of wValue in get string descriptor
+ * @buf: at least 256 bytes
+ *
+ * Finds the UTF-8 string matching the ID, and converts it into a
+ * string descriptor in utf16-le.
+ * Returns length of descriptor (always even) or negative errno
+ *
+ * If your driver needs stings in multiple languages, you'll probably
+ * "switch (wIndex) { ... }"  in your ep0 string descriptor logic,
+ * using this routine after choosing which set of UTF-8 strings to use.
+ * Note that US-ASCII is a strict subset of UTF-8; any string bytes with
+ * the eighth bit set will be multibyte UTF-8 characters, not ISO-8859/1
+ * characters (which are also widely used in C strings).
+ */
+int
+usb_gadget_get_string (struct usb_gadget_strings *table, int id, u8 *buf)
+{
+	struct usb_string	*s;
+	int			len;
+
+	/* descriptor 0 has the language id */
+	if (id == 0) {
+		buf [0] = 4;
+		buf [1] = USB_DT_STRING;
+		buf [2] = (u8) table->language;
+		buf [3] = (u8) (table->language >> 8);
+		return 4;
+	}
+	for (s = table->strings; s && s->s; s++)
+		if (s->id == id)
+			break;
+
+	/* unrecognized: stall. */
+	if (!s || !s->s)
+		return -EINVAL;
+
+	/* string descriptors have length, tag, then UTF16-LE text */
+	len = min ((size_t) 126, strlen (s->s));
+	memset (buf + 2, 0, 2 * len);	/* zero all the bytes */
+	len = utf8_to_utf16le(s->s, (__le16 *)&buf[2], len);
+	if (len < 0)
+		return -EINVAL;
+	buf [0] = (len + 1) * 2;
+	buf [1] = USB_DT_STRING;
+	return buf [0];
+}
+