[PATCH] USB: add omap_udc driver

This patch adds a UDC driver for OMAP, which should work on most
OMAP processors.  It's been tested most on OMAP 1611/5912.  The
driver supports all USB transfer types (including ISO), has limited
DMA support, and seems to work with all gadget drivers, both to
Linux hosts and to MS-Windows ones.

One reason this UDC is particularly interesting is that recent OMAP
processors all support "USB On-The-Go" (OTG) ... and this driver
supports it on at least "H2-like" boards.

Another reason is that the UDC is very flexible and fully featured;
gadget drivers can allocate fifo space to endpoints in the way that's
most convenient for the application.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

drivers/usb/gadget/Kconfig

@@ -175,6 +175,41 @@ config USB_DUMMY_HCD
 	depends on USB_GADGET_DUMMY_HCD
 	default USB_GADGET
 
+config USB_GADGET_OMAP
+	boolean "OMAP USB Device Controller"
+	depends on ARCH_OMAP
+	select ISP1301_OMAP if MACH_OMAP_H2
+	help
+	   Many Texas Instruments OMAP processors have flexible full
+	   speed USB device controllers, with support for up to 30
+	   endpoints (plus endpoint zero).  This driver supports the
+	   controller in the OMAP 1611, and should work with controllers
+	   in other OMAP processors too, given minor tweaks.
+
+	   Say "y" to link the driver statically, or "m" to build a
+	   dynamically linked module called "omap_udc" and force all
+	   gadget drivers to also be dynamically linked.
+
+config USB_OMAP
+	tristate
+	depends on USB_GADGET_OMAP
+	default USB_GADGET
+
+config USB_OTG
+	boolean "OTG Support"
+	depends on USB_GADGET_OMAP && ARCH_OMAP_OTG && USB_OHCI_HCD
+	help
+	   The most notable feature of USB OTG is support for a
+	   "Dual-Role" device, which can act as either a device
+	   or a host.  The initial role choice can be changed
+	   later, when two dual-role devices talk to each other.
+
+	   Select this only if your OMAP board has a Mini-AB connector.
+
+config USB_OMAP_PROC
+	boolean "/proc/driver/udc file"
+	depends on USB_GADGET_OMAP
+
 endchoice
 
 config USB_GADGET_DUALSPEED

drivers/usb/gadget/Makefile

@@ -5,6 +5,8 @@ obj-$(CONFIG_USB_DUMMY_HCD)	+= dummy_hcd.o
 obj-$(CONFIG_USB_NET2280)	+= net2280.o
 obj-$(CONFIG_USB_PXA2XX)	+= pxa2xx_udc.o
 obj-$(CONFIG_USB_GOKU)		+= goku_udc.o
+obj-$(CONFIG_USB_OMAP)		+= omap_udc.o
+obj-$(CONFIG_USB_LH7A40X)	+= lh7a40x_udc.o
 
 #
 # USB gadget drivers

drivers/usb/gadget/omap_udc.c

+/*
+ * omap_udc.c -- for OMAP 1610 udc, with OTG support
+ *
+ * Copyright (C) 2004 Texas Instruments, Inc.
+ * 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
+ */
+
+#undef	DEBUG
+#undef	VERBOSE
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/ioport.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/timer.h>
+#include <linux/list.h>
+#include <linux/interrupt.h>
+#include <linux/proc_fs.h>
+#include <linux/mm.h>
+#include <linux/moduleparam.h>
+#include <linux/device.h>
+#include <linux/usb_ch9.h>
+#include <linux/usb_gadget.h>
+#include <linux/usb_otg.h>
+#include <linux/dma-mapping.h>
+
+#include <asm/byteorder.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/system.h>
+#include <asm/unaligned.h>
+#include <asm/mach-types.h>
+
+#include <asm/arch/dma.h>
+#include <asm/arch/mux.h>
+#include <asm/arch/usb.h>
+
+#include "omap_udc.h"
+
+#undef	USB_TRACE
+
+/* OUT-dma seems to be behaving */
+#define	USE_DMA
+
+/* ISO too */
+#define	USE_ISO
+
+
+#define	DRIVER_DESC	"OMAP UDC driver"
+#define	DRIVER_VERSION	"24 August 2004"
+
+#define	DMA_ADDR_INVALID	(~(dma_addr_t)0)
+
+
+/*
+ * The OMAP UDC needs _very_ early endpoint setup:  before enabling the
+ * D+ pullup to allow enumeration.  That's too early for the gadget
+ * framework to use from usb_endpoint_enable(), which happens after
+ * enumeration as part of activating an interface.  (But if we add an
+ * optional new "UDC not yet running" state to the gadget driver model,
+ * even just during driver binding, the endpoint autoconfig logic is the
+ * natural spot to manufacture new endpoints.)
+ *
+ * So instead of using endpoint enable calls to control the hardware setup,
+ * this driver defines a "fifo mode" parameter.  It's used during driver
+ * initialization to choose among a set of pre-defined endpoint configs.
+ * See omap_udc_setup() for available modes, or to add others.  That code
+ * lives in an init section, so use this driver as a module if you need
+ * to change the fifo mode after the kernel boots.
+ *
+ * Gadget drivers normally ignore endpoints they don't care about, and
+ * won't include them in configuration descriptors.  That means only
+ * misbehaving hosts would even notice they exist.
+ */
+#ifdef	USE_ISO
+static unsigned fifo_mode = 3;
+#else
+static unsigned fifo_mode = 0;
+#endif
+
+/* "modprobe omap_udc fifo_mode=42", or else as a kernel
+ * boot parameter "omap_udc:fifo_mode=42"
+ */
+module_param (fifo_mode, uint, 0);
+MODULE_PARM_DESC (fifo_mode, "endpoint setup (0 == default)");
+
+
+#ifdef	USE_DMA
+static unsigned use_dma = 1;
+
+/* "modprobe omap_udc use_dma=y", or else as a kernel
+ * boot parameter "omap_udc:use_dma=y"
+ */
+module_param (use_dma, bool, 0);
+MODULE_PARM_DESC (use_dma, "enable/disable DMA");
+#else	/* !USE_DMA */
+
+/* save a bit of code */
+#define	use_dma		0
+#endif	/* !USE_DMA */
+
+
+static const char driver_name [] = "omap_udc";
+static const char driver_desc [] = DRIVER_DESC;
+
+/*-------------------------------------------------------------------------*/
+
+/* there's a notion of "current endpoint" for modifying endpoint
+ * state, and PIO access to its FIFO.  
+ */
+
+static void use_ep(struct omap_ep *ep, u16 select)
+{
+	u16	num = ep->bEndpointAddress & 0x0f;
+
+	if (ep->bEndpointAddress & USB_DIR_IN)
+		num |= UDC_EP_DIR;
+	UDC_EP_NUM_REG = num | select;
+	/* when select, MUST deselect later !! */
+}
+
+static inline void deselect_ep(void)
+{
+	UDC_EP_NUM_REG &= ~UDC_EP_SEL;
+	/* 6 wait states before TX will happen */
+}
+
+static void dma_channel_claim(struct omap_ep *ep, unsigned preferred);
+
+/*-------------------------------------------------------------------------*/
+
+static int omap_ep_enable(struct usb_ep *_ep,
+		const struct usb_endpoint_descriptor *desc)
+{
+	struct omap_ep	*ep = container_of(_ep, struct omap_ep, ep);
+	struct omap_udc	*udc;
+	unsigned long	flags;
+	u16		maxp;
+
+	/* catch various bogus parameters */
+	if (!_ep || !desc || ep->desc
+			|| desc->bDescriptorType != USB_DT_ENDPOINT
+			|| ep->bEndpointAddress != desc->bEndpointAddress
+			|| ep->maxpacket < le16_to_cpu
+						(desc->wMaxPacketSize)) {
+		DBG("%s, bad ep or descriptor\n", __FUNCTION__);
+		return -EINVAL;
+	}
+	maxp = le16_to_cpu (desc->wMaxPacketSize);
+	if ((desc->bmAttributes == USB_ENDPOINT_XFER_BULK
+				&& maxp != ep->maxpacket)
+			|| desc->wMaxPacketSize > ep->maxpacket
+			|| !desc->wMaxPacketSize) {
+		DBG("%s, bad %s maxpacket\n", __FUNCTION__, _ep->name);
+		return -ERANGE;
+	}
+
+#ifdef	USE_ISO
+	if ((desc->bmAttributes == USB_ENDPOINT_XFER_ISOC
+				&& desc->bInterval != 1)) {
+		/* hardware wants period = 1; USB allows 2^(Interval-1) */
+		DBG("%s, unsupported ISO period %dms\n", _ep->name,
+				1 << (desc->bInterval - 1));
+		return -EDOM;
+	}
+#else
+	if (desc->bmAttributes == USB_ENDPOINT_XFER_ISOC) {
+		DBG("%s, ISO nyet\n", _ep->name);
+		return -EDOM;
+	}
+#endif
+
+	/* xfer types must match, except that interrupt ~= bulk */
+	if (ep->bmAttributes != desc->bmAttributes
+			&& ep->bmAttributes != USB_ENDPOINT_XFER_BULK
+			&& desc->bmAttributes != USB_ENDPOINT_XFER_INT) {
+		DBG("%s, %s type mismatch\n", __FUNCTION__, _ep->name);
+		return -EINVAL;
+	}
+
+	udc = ep->udc;
+	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
+		DBG("%s, bogus device state\n", __FUNCTION__);
+		return -ESHUTDOWN;
+	}
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	ep->desc = desc;
+	ep->irqs = 0;
+	ep->stopped = 0;
+	ep->ep.maxpacket = maxp;
+
+	/* set endpoint to initial state */
+	ep->dma_channel = 0;
+	ep->has_dma = 0;
+	ep->lch = -1;
+	use_ep(ep, UDC_EP_SEL);
+	UDC_CTRL_REG = UDC_RESET_EP;
+	ep->ackwait = 0;
+	deselect_ep();
+
+	if (ep->bmAttributes == USB_ENDPOINT_XFER_ISOC)
+		list_add(&ep->iso, &udc->iso);
+
+	/* maybe assign a DMA channel to this endpoint */
+	if (use_dma && desc->bmAttributes == USB_ENDPOINT_XFER_BULK
+			&& !(ep->bEndpointAddress & USB_DIR_IN))
+			/* FIXME ISO can dma, but prefers first channel.
+			 * IN can dma, but lacks debugging.
+			 */
+		dma_channel_claim(ep, 0);
+
+	/* PIO OUT may RX packets */
+	if (desc->bmAttributes != USB_ENDPOINT_XFER_ISOC
+			&& !ep->has_dma
+			&& !(ep->bEndpointAddress & USB_DIR_IN))
+		UDC_CTRL_REG = UDC_SET_FIFO_EN;
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+	VDBG("%s enabled\n", _ep->name);
+	return 0;
+}
+
+static void nuke(struct omap_ep *, int status);
+
+static int omap_ep_disable(struct usb_ep *_ep)
+{
+	struct omap_ep	*ep = container_of(_ep, struct omap_ep, ep);
+	unsigned long	flags;
+
+	if (!_ep || !ep->desc) {
+		DBG("%s, %s not enabled\n", __FUNCTION__,
+			_ep ? ep->ep.name : NULL);
+		return -EINVAL;
+	}
+
+	spin_lock_irqsave(&ep->udc->lock, flags);
+	ep->desc = 0;
+	nuke (ep, -ESHUTDOWN);
+	ep->ep.maxpacket = ep->maxpacket;
+	ep->has_dma = 0;
+	UDC_CTRL_REG = UDC_SET_HALT;
+	list_del_init(&ep->iso);
+
+	spin_unlock_irqrestore(&ep->udc->lock, flags);
+
+	VDBG("%s disabled\n", _ep->name);
+	return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static struct usb_request *
+omap_alloc_request(struct usb_ep *ep, int gfp_flags)
+{
+	struct omap_req	*req;
+
+	req = kmalloc(sizeof *req, gfp_flags);
+	if (req) {
+		memset (req, 0, sizeof *req);
+		req->req.dma = DMA_ADDR_INVALID;
+		INIT_LIST_HEAD (&req->queue);
+	}
+	return &req->req;
+}
+
+static void
+omap_free_request(struct usb_ep *ep, struct usb_request *_req)
+{
+	struct omap_req	*req = container_of(_req, struct omap_req, req);
+
+	if (_req)
+		kfree (req);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void *
+omap_alloc_buffer(
+	struct usb_ep	*_ep,
+	unsigned	bytes,
+	dma_addr_t	*dma,
+	int		gfp_flags
+)
+{
+	void		*retval;
+	struct omap_ep	*ep;
+
+	ep = container_of(_ep, struct omap_ep, ep);
+	if (use_dma && ep->has_dma) {
+		static int	warned;
+		if (!warned && bytes < PAGE_SIZE) {
+			dev_warn(ep->udc->gadget.dev.parent,
+				"using dma_alloc_coherent for "
+				"small allocations wastes memory\n");
+			warned++;
+		}
+		return dma_alloc_coherent(ep->udc->gadget.dev.parent,
+				bytes, dma, gfp_flags);
+	}
+
+	retval = kmalloc(bytes, gfp_flags);
+	if (retval)
+		*dma = virt_to_phys(retval);
+	return retval;
+}
+
+static void omap_free_buffer(
+	struct usb_ep	*_ep,
+	void		*buf,
+	dma_addr_t	dma,
+	unsigned	bytes
+)
+{
+	struct omap_ep	*ep;
+
+	ep = container_of(_ep, struct omap_ep, ep);
+	if (use_dma && _ep && ep->has_dma)
+		dma_free_coherent(ep->udc->gadget.dev.parent, bytes, buf, dma);
+	else
+		kfree (buf);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void
+done(struct omap_ep *ep, struct omap_req *req, int status)
+{
+	unsigned		stopped = ep->stopped;
+
+	list_del_init(&req->queue);
+
+	if (req->req.status == -EINPROGRESS)
+		req->req.status = status;
+	else
+		status = req->req.status;
+
+	if (use_dma && ep->has_dma) {
+		if (req->mapped) {
+			dma_unmap_single(ep->udc->gadget.dev.parent,
+				req->req.dma, req->req.length,
+				(ep->bEndpointAddress & USB_DIR_IN)
+					? DMA_TO_DEVICE
+					: DMA_FROM_DEVICE);
+			req->req.dma = DMA_ADDR_INVALID;
+			req->mapped = 0;
+		} else
+			dma_sync_single_for_cpu(ep->udc->gadget.dev.parent,
+				req->req.dma, req->req.length,
+				(ep->bEndpointAddress & USB_DIR_IN)
+					? DMA_TO_DEVICE
+					: DMA_FROM_DEVICE);
+	}
+
+#ifndef	USB_TRACE
+	if (status && status != -ESHUTDOWN)
+#endif
+		VDBG("complete %s req %p stat %d len %u/%u\n",
+			ep->ep.name, &req->req, status,
+			req->req.actual, req->req.length);
+
+	/* don't modify queue heads during completion callback */
+	ep->stopped = 1;
+	spin_unlock(&ep->udc->lock);
+	req->req.complete(&ep->ep, &req->req);
+	spin_lock(&ep->udc->lock);
+	ep->stopped = stopped;
+}
+
+/*-------------------------------------------------------------------------*/
+
+#define	FIFO_FULL	(UDC_NON_ISO_FIFO_FULL | UDC_ISO_FIFO_FULL)
+#define	FIFO_UNWRITABLE	(UDC_EP_HALTED | FIFO_FULL)
+
+#define FIFO_EMPTY	(UDC_NON_ISO_FIFO_EMPTY | UDC_ISO_FIFO_EMPTY)
+#define FIFO_UNREADABLE (UDC_EP_HALTED | FIFO_EMPTY)
+
+static inline int 
+write_packet(u8 *buf, struct omap_req *req, unsigned max)
+{
+	unsigned	len;
+	u16		*wp;
+
+	len = min(req->req.length - req->req.actual, max);
+	req->req.actual += len;
+
+	max = len;
+	if (likely((((int)buf) & 1) == 0)) {
+		wp = (u16 *)buf;
+		while (max >= 2) {
+			UDC_DATA_REG = *wp++;
+			max -= 2;
+		}
+		buf = (u8 *)wp;
+	}
+	while (max--)
+		*(volatile u8 *)&UDC_DATA_REG = *buf++;
+	return len;
+}
+
+// FIXME change r/w fifo calling convention
+
+
+// return:  0 = still running, 1 = completed, negative = errno
+static int write_fifo(struct omap_ep *ep, struct omap_req *req)
+{
+	u8		*buf;
+	unsigned	count;
+	int		is_last;
+	u16		ep_stat;
+
+	buf = req->req.buf + req->req.actual;
+	prefetch(buf);
+
+	/* PIO-IN isn't double buffered except for iso */
+	ep_stat = UDC_STAT_FLG_REG;
+	if (ep_stat & FIFO_UNWRITABLE)
+		return 0;
+
+	count = ep->ep.maxpacket;
+	count = write_packet(buf, req, count);
+	UDC_CTRL_REG = UDC_SET_FIFO_EN;
+	ep->ackwait = 1;
+
+	/* last packet is often short (sometimes a zlp) */
+	if (count != ep->ep.maxpacket)
+		is_last = 1;
+	else if (req->req.length == req->req.actual
+			&& !req->req.zero)
+		is_last = 1;
+	else
+		is_last = 0;
+
+	/* NOTE:  requests complete when all IN data is in a
+	 * FIFO (or sometimes later, if a zlp was needed).
+	 * Use usb_ep_fifo_status() where needed.
+	 */
+	if (is_last)
+		done(ep, req, 0);
+	return is_last;
+}
+
+static inline int 
+read_packet(u8 *buf, struct omap_req *req, unsigned avail)
+{
+	unsigned	len;
+	u16		*wp;
+
+	len = min(req->req.length - req->req.actual, avail);
+	req->req.actual += len;
+	avail = len;
+
+	if (likely((((int)buf) & 1) == 0)) {
+		wp = (u16 *)buf;
+		while (avail >= 2) {
+			*wp++ = UDC_DATA_REG;
+			avail -= 2;
+		}
+		buf = (u8 *)wp;
+	}
+	while (avail--)
+		*buf++ = *(volatile u8 *)&UDC_DATA_REG;
+	return len;
+}
+
+// return:  0 = still running, 1 = queue empty, negative = errno
+static int read_fifo(struct omap_ep *ep, struct omap_req *req)
+{
+	u8		*buf;
+	unsigned	count, avail;
+	int		is_last;
+
+	buf = req->req.buf + req->req.actual;
+	prefetchw(buf);
+
+	for (;;) {
+		u16	ep_stat = UDC_STAT_FLG_REG;
+
+		is_last = 0;
+		if (ep_stat & FIFO_UNREADABLE)
+			break;
+
+		if (ep_stat & (UDC_NON_ISO_FIFO_FULL|UDC_ISO_FIFO_FULL))
+			avail = ep->ep.maxpacket;
+		else 
+			avail = UDC_RXFSTAT_REG;
+		count = read_packet(buf, req, avail);
+
+		// FIXME double buffered PIO OUT wasn't behaving...
+
+		/* partial packet reads may not be errors */
+		if (count < ep->ep.maxpacket) {
+			is_last = 1;
+			/* overflowed this request?  flush extra data */
+			if (count != avail) {
+				req->req.status = -EOVERFLOW;
+				avail -= count;
+				while (avail--)
+					(void) *(volatile u8 *)&UDC_DATA_REG;
+			}
+		} else if (req->req.length == req->req.actual)
+			is_last = 1;
+		else
+			is_last = 0;
+
+		if (!ep->bEndpointAddress)
+			break;
+		if (!ep->double_buf) {
+			UDC_CTRL_REG = UDC_SET_FIFO_EN;
+			if (!is_last)
+				break;
+		}
+
+		if (is_last) {
+			done(ep, req, 0);
+			if (list_empty(&ep->queue) || !ep->double_buf)
+				break;
+			req = container_of(ep->queue.next,
+					struct omap_req, queue);
+			is_last = 0;
+		}
+	}
+	return is_last;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* Each USB transfer request using DMA maps to one or more DMA transfers.
+ * When DMA completion isn't request completion, the UDC continues with
+ * the next DMA transfer for that USB transfer.
+ */
+
+static void next_in_dma(struct omap_ep *ep, struct omap_req *req)
+{
+	u16		txdma_ctrl;
+	unsigned	length = req->req.length - req->req.actual;
+
+	/* measure length in either bytes or packets */
+	if (length <= (UDC_TXN_TSC + 1)) {
+		txdma_ctrl = UDC_TXN_EOT | length;
+		omap_set_dma_transfer_params(ep->lch, OMAP_DMA_DATA_TYPE_S8,
+				length, 1, OMAP_DMA_SYNC_ELEMENT);
+	} else {
+		length = max(length / ep->maxpacket,
+				(unsigned) UDC_TXN_TSC + 1);
+ 		txdma_ctrl = length;
+		omap_set_dma_transfer_params(ep->lch, OMAP_DMA_DATA_TYPE_S8,
+				ep->ep.maxpacket, length,
+				OMAP_DMA_SYNC_ELEMENT);
+		length *= ep->maxpacket;
+	}
+
+	omap_set_dma_src_params(ep->lch, OMAP_DMA_PORT_EMIFF,
+		OMAP_DMA_AMODE_POST_INC, req->req.dma + req->req.actual);
+
+	omap_start_dma(ep->lch);
+	UDC_DMA_IRQ_EN_REG |= UDC_TX_DONE_IE(ep->dma_channel);
+	UDC_TXDMA_REG(ep->dma_channel) = UDC_TXN_START | txdma_ctrl;
+	req->dma_bytes = length;
+}
+
+static void finish_in_dma(struct omap_ep *ep, struct omap_req *req, int status)
+{
+	if (status == 0) {
+		req->req.actual += req->dma_bytes;
+
+		/* return if this request needs to send data or zlp */
+		if (req->req.actual < req->req.length)
+			return;
+		if (req->req.zero
+				&& req->dma_bytes != 0
+				&& (req->req.actual % ep->maxpacket) == 0)
+			return;
+	} else {
+		u32	last;
+
+		// FIXME this surely isn't #bytes transferred
+		last = (omap_readw(OMAP_DMA_CSSA_U(ep->lch)) << 16)
+				| omap_readw(OMAP_DMA_CSSA_L(ep->lch));
+		req->req.actual = last - req->req.dma;
+	}
+
+	/* tx completion */
+	omap_stop_dma(ep->lch);
+	UDC_DMA_IRQ_EN_REG &= ~UDC_TX_DONE_IE(ep->dma_channel);
+	done(ep, req, status);
+}
+
+static void next_out_dma(struct omap_ep *ep, struct omap_req *req)
+{
+	unsigned packets;
+
+	/* NOTE:  we filtered out "short reads" before, so we know
+	 * the buffer has only whole numbers of packets.
+	 */
+
+	/* set up this DMA transfer, enable the fifo, start */
+	packets = (req->req.length - req->req.actual) / ep->ep.maxpacket;
+	packets = min(packets, (unsigned)UDC_RXN_TC + 1);
+	req->dma_bytes = packets * ep->ep.maxpacket;
+	omap_set_dma_transfer_params(ep->lch, OMAP_DMA_DATA_TYPE_S8,
+			ep->ep.maxpacket, packets,
+			OMAP_DMA_SYNC_ELEMENT);
+	omap_set_dma_dest_params(ep->lch, OMAP_DMA_PORT_EMIFF,
+		OMAP_DMA_AMODE_POST_INC, req->req.dma + req->req.actual);
+
+	UDC_RXDMA_REG(ep->dma_channel) = UDC_RXN_STOP | (packets - 1);
+	UDC_DMA_IRQ_EN_REG |= UDC_RX_EOT_IE(ep->dma_channel);
+	UDC_EP_NUM_REG = (ep->bEndpointAddress & 0xf);
+	UDC_CTRL_REG = UDC_SET_FIFO_EN;
+
+	omap_start_dma(ep->lch);
+}
+
+static void
+finish_out_dma(struct omap_ep *ep, struct omap_req *req, int status)
+{
+	u16	count;
+
+	/* FIXME must be a better way to see how much dma
+	 * happened, even when it never got going...
+	 */
+	count = omap_readw(OMAP_DMA_CDAC(ep->lch));
+	count -= 0xffff & (req->req.dma + req->req.actual);
+	count += req->req.actual;
+	if (count <= req->req.length)
+		req->req.actual = count;
+	
+	if (count != req->dma_bytes || status)
+		omap_stop_dma(ep->lch);
+
+	/* if this wasn't short, request may need another transfer */
+	else if (req->req.actual < req->req.length)
+		return;
+
+	/* rx completion */
+	UDC_DMA_IRQ_EN_REG &= ~UDC_RX_EOT_IE(ep->dma_channel);
+	done(ep, req, status);
+}
+
+static void dma_irq(struct omap_udc *udc, u16 irq_src)
+{
+	u16		dman_stat = UDC_DMAN_STAT_REG;
+	struct omap_ep	*ep;
+	struct omap_req	*req;
+
+	/* IN dma: tx to host */
+	if (irq_src & UDC_TXN_DONE) {
+		ep = &udc->ep[16 + UDC_DMA_TX_SRC(dman_stat)];
+		ep->irqs++;
+		/* can see TXN_DONE after dma abort */
+		if (!list_empty(&ep->queue)) {
+			req = container_of(ep->queue.next,
+						struct omap_req, queue);
+			finish_in_dma(ep, req, 0);
+		}
+		UDC_IRQ_SRC_REG = UDC_TXN_DONE;
+
+		if (!list_empty (&ep->queue)) {
+			req = container_of(ep->queue.next,
+					struct omap_req, queue);
+			next_in_dma(ep, req);
+		}
+	}
+
+	/* OUT dma: rx from host */
+	if (irq_src & UDC_RXN_EOT) {
+		ep = &udc->ep[UDC_DMA_RX_SRC(dman_stat)];
+		ep->irqs++;
+		/* can see RXN_EOT after dma abort */
+		if (!list_empty(&ep->queue)) {
+			req = container_of(ep->queue.next,
+					struct omap_req, queue);
+			finish_out_dma(ep, req, 0);
+		}
+		UDC_IRQ_SRC_REG = UDC_RXN_EOT;
+
+		if (!list_empty (&ep->queue)) {
+			req = container_of(ep->queue.next,
+					struct omap_req, queue);
+			next_out_dma(ep, req);
+		}
+	}
+
+	if (irq_src & UDC_RXN_CNT) {
+		ep = &udc->ep[UDC_DMA_RX_SRC(dman_stat)];
+		DBG("%s, RX_CNT irq?\n", ep->ep.name);
+		UDC_IRQ_SRC_REG = UDC_RXN_CNT;
+	}
+}
+
+static void dma_error(int lch, u16 ch_status, void *data)
+{
+	struct omap_ep	*ep = data;
+
+	/* if ch_status & OMAP_DMA_DROP_IRQ ... */
+	/* if ch_status & OMAP_DMA_TOUT_IRQ ... */
+	ERR("%s dma error, lch %d status %02x\n", ep->ep.name, lch, ch_status);
+
+	/* complete current transfer ... */
+}
+
+static void dma_channel_claim(struct omap_ep *ep, unsigned channel)
+{
+	u16	reg;
+	int	status, restart, is_in;
+
+	is_in = ep->bEndpointAddress & USB_DIR_IN;
+	if (is_in)
+		reg = UDC_TXDMA_CFG_REG;
+	else
+		reg = UDC_RXDMA_CFG_REG;
+	reg |= 1 << 12;		/* "pulse" activated */
+
+	ep->dma_channel = 0;
+	ep->lch = -1;
+	if (channel == 0 || channel > 3) {
+		if ((reg & 0x0f00) == 0)
+			channel = 3;
+		else if ((reg & 0x00f0) == 0)
+			channel = 2;
+		else if ((reg & 0x000f) == 0)	/* preferred for ISO */
+			channel = 1;
+		else {
+			status = -EMLINK;
+			goto just_restart;
+		}
+	}
+	reg |= (0x0f & ep->bEndpointAddress) << (4 * (channel - 1));
+	ep->dma_channel = channel;
+
+	if (is_in) {
+		status = omap_request_dma(OMAP_DMA_USB_W2FC_TX0 - 1 + channel,
+			ep->ep.name, dma_error, ep, &ep->lch);
+		if (status == 0) {
+			UDC_TXDMA_CFG_REG = reg;
+			omap_set_dma_dest_params(ep->lch,
+				OMAP_DMA_PORT_TIPB,
+				OMAP_DMA_AMODE_CONSTANT,
+				(unsigned long) io_v2p((u32)&UDC_DATA_DMA_REG));
+		}
+	} else {
+		status = omap_request_dma(OMAP_DMA_USB_W2FC_RX0 - 1 + channel,
+			ep->ep.name, dma_error, ep, &ep->lch);
+		if (status == 0) {
+			UDC_RXDMA_CFG_REG = reg;
+			omap_set_dma_src_params(ep->lch,
+				OMAP_DMA_PORT_TIPB,
+				OMAP_DMA_AMODE_CONSTANT,
+				(unsigned long) io_v2p((u32)&UDC_DATA_DMA_REG));
+		}
+	}
+	if (status)
+		ep->dma_channel = 0;
+	else {
+		ep->has_dma = 1;
+		omap_disable_dma_irq(ep->lch, OMAP_DMA_BLOCK_IRQ);
+
+		/* channel type P: hw synch (fifo) */
+		omap_writew(2, OMAP_DMA_LCH_CTRL(ep->lch));
+	}
+
+just_restart:
+	/* restart any queue, even if the claim failed  */
+	restart = !ep->stopped && !list_empty(&ep->queue);
+
+	if (status)
+		DBG("%s no dma channel: %d%s\n", ep->ep.name, status,
+			restart ? " (restart)" : "");
+	else
+		DBG("%s claimed %cxdma%d lch %d%s\n", ep->ep.name,
+			is_in ? 't' : 'r',
+			ep->dma_channel - 1, ep->lch,
+			restart ? " (restart)" : "");
+
+	if (restart) {
+		struct omap_req	*req;
+		req = container_of(ep->queue.next, struct omap_req, queue);
+		if (ep->has_dma)
+			(is_in ? next_in_dma : next_out_dma)(ep, req);
+		else {
+			use_ep(ep, UDC_EP_SEL);
+			(is_in ? write_fifo : read_fifo)(ep, req);
+			deselect_ep();
+			/* IN: 6 wait states before it'll tx */
+		}
+	}
+}
+
+static void dma_channel_release(struct omap_ep *ep)
+{
+	int		shift = 4 * (ep->dma_channel - 1);
+	u16		mask = 0x0f << shift;
+	struct omap_req	*req;
+	int		active;
+
+	/* abort any active usb transfer request */
+	if (!list_empty(&ep->queue))
+		req = container_of(ep->queue.next, struct omap_req, queue);
+	else
+		req = 0;
+
+	active = ((1 << 7) & omap_readl(OMAP_DMA_CCR(ep->lch))) != 0;
+
+	DBG("%s release %s %cxdma%d %p\n", ep->ep.name,
+			active ? "active" : "idle",
+			(ep->bEndpointAddress & USB_DIR_IN) ? 't' : 'r',
+			ep->dma_channel - 1, req);
+
+	/* wait till current packet DMA finishes, and fifo empties */
+	if (ep->bEndpointAddress & USB_DIR_IN) {
+		UDC_TXDMA_CFG_REG &= ~mask;
+
+		if (req) {
+			if (active)
+				udelay(50);
+			finish_in_dma(ep, req, -ECONNRESET);
+			if (UDC_TXDMA_CFG_REG & mask)
+				WARN("%s, SPIN abort TX dma\n", ep->ep.name);
+		}
+
+		/* host may empty the fifo (or not...) */
+		while (UDC_TXDMA_CFG_REG & mask)
+			udelay(10);
+
+	} else {
+		UDC_RXDMA_CFG_REG &= ~mask;
+
+		/* dma empties the fifo */
+		while (active && (UDC_RXDMA_CFG_REG & mask))
+			udelay(10);
+		omap_stop_dma(ep->lch);
+		if (req)
+			finish_out_dma(ep, req, -ECONNRESET);
+	}
+	omap_free_dma(ep->lch);
+	ep->dma_channel = 0;
+	ep->lch = -1;
+	/* has_dma still set, till endpoint is fully quiesced */
+}
+
+
+/*-------------------------------------------------------------------------*/
+
+static int
+omap_ep_queue(struct usb_ep *_ep, struct usb_request *_req, int gfp_flags)
+{
+	struct omap_ep	*ep = container_of(_ep, struct omap_ep, ep);
+	struct omap_req	*req = container_of(_req, struct omap_req, req);
+	struct omap_udc	*udc;
+	unsigned long	flags;
+	int		is_iso = 0;
+
+	/* catch various bogus parameters */
+	if (!_req || !req->req.complete || !req->req.buf
+			|| !list_empty(&req->queue)) {
+		DBG("%s, bad params\n", __FUNCTION__);
+		return -EINVAL;
+	}
+	if (!_ep || (!ep->desc && ep->bEndpointAddress)) {
+		DBG("%s, bad ep\n", __FUNCTION__);
+		return -EINVAL;
+	}
+	if (ep->bmAttributes == USB_ENDPOINT_XFER_ISOC) {
+		if (req->req.length > ep->ep.maxpacket)
+			return -EMSGSIZE;
+		is_iso = 1;
+	}
+
+	/* this isn't bogus, but OMAP DMA isn't the only hardware to
+	 * have a hard time with partial packet reads...  reject it.
+	 */
+	if (use_dma
+			&& ep->has_dma
+			&& ep->bEndpointAddress != 0
+			&& (ep->bEndpointAddress & USB_DIR_IN) == 0
+			&& (req->req.length % ep->ep.maxpacket) != 0) {
+		DBG("%s, no partial packet OUT reads\n", __FUNCTION__);
+		return -EMSGSIZE;
+	}
+
+	udc = ep->udc;
+	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN)
+		return -ESHUTDOWN;
+
+	if (use_dma && ep->has_dma) {
+		if (req->req.dma == DMA_ADDR_INVALID) {
+			req->req.dma = dma_map_single(
+				ep->udc->gadget.dev.parent,
+				req->req.buf,
+				req->req.length,
+				(ep->bEndpointAddress & USB_DIR_IN)
+					? DMA_TO_DEVICE
+					: DMA_FROM_DEVICE);
+			req->mapped = 1;
+		} else {
+			dma_sync_single_for_device(
+				ep->udc->gadget.dev.parent,
+				req->req.dma, req->req.length,
+				(ep->bEndpointAddress & USB_DIR_IN)
+					? DMA_TO_DEVICE
+					: DMA_FROM_DEVICE);
+			req->mapped = 0;
+		}
+	}
+
+	VDBG("%s queue req %p, len %d buf %p\n",
+		ep->ep.name, _req, _req->length, _req->buf);
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	req->req.status = -EINPROGRESS;
+	req->req.actual = 0;
+
+	/* maybe kickstart non-iso i/o queues */
+	if (is_iso)
+		UDC_IRQ_EN_REG |= UDC_SOF_IE;
+	else if (list_empty(&ep->queue) && !ep->stopped && !ep->ackwait) {
+		int	is_in;
+
+		if (ep->bEndpointAddress == 0) {
+			if (!udc->ep0_pending || !list_empty (&ep->queue)) {
+				spin_unlock_irqrestore(&udc->lock, flags);
+				return -EL2HLT;
+			}
+
+			/* empty DATA stage? */
+			is_in = udc->ep0_in;
+			if (!req->req.length) {
+
+				/* chip became CONFIGURED or ADDRESSED
+				 * earlier; drivers may already have queued
+				 * requests to non-control endpoints
+				 */
+				if (udc->ep0_set_config) {
+					u16	irq_en = UDC_IRQ_EN_REG;
+
+					irq_en |= UDC_DS_CHG_IE | UDC_EP0_IE;
+					if (!udc->ep0_reset_config)
+						irq_en |= UDC_EPN_RX_IE
+							| UDC_EPN_TX_IE;
+					UDC_IRQ_EN_REG = irq_en;
+				}
+
+				/* STATUS is reverse direction */
+				UDC_EP_NUM_REG = is_in
+						? UDC_EP_SEL
+						: (UDC_EP_SEL|UDC_EP_DIR);
+				UDC_CTRL_REG = UDC_CLR_EP;
+				UDC_CTRL_REG = UDC_SET_FIFO_EN;
+				UDC_EP_NUM_REG = udc->ep0_in ? 0 : UDC_EP_DIR;
+
+				/* cleanup */
+				udc->ep0_pending = 0;
+				done(ep, req, 0);
+				req = 0;
+
+			/* non-empty DATA stage */
+			} else if (is_in) {
+				UDC_EP_NUM_REG = UDC_EP_SEL|UDC_EP_DIR;
+			} else {
+				if (udc->ep0_setup)
+					goto irq_wait;
+				UDC_EP_NUM_REG = UDC_EP_SEL;
+			}
+		} else {
+			is_in = ep->bEndpointAddress & USB_DIR_IN;
+			if (!ep->has_dma)
+				use_ep(ep, UDC_EP_SEL);
+			/* if ISO: SOF IRQs must be enabled/disabled! */
+		}
+
+		if (ep->has_dma)
+			(is_in ? next_in_dma : next_out_dma)(ep, req);
+		else if (req) {
+			if ((is_in ? write_fifo : read_fifo)(ep, req) == 1)
+				req = 0;
+			deselect_ep();
+			/* IN: 6 wait states before it'll tx */
+		}
+	}
+
+irq_wait:
+	/* irq handler advances the queue */
+	if (req != 0)
+		list_add_tail(&req->queue, &ep->queue);
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return 0;
+}
+
+static int omap_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
+{
+	struct omap_ep	*ep = container_of(_ep, struct omap_ep, ep);
+	struct omap_req	*req;
+	unsigned long	flags;
+
+	if (!_ep || !_req)
+		return -EINVAL;
+
+	spin_lock_irqsave(&ep->udc->lock, flags);
+
+	/* make sure it's actually queued on this endpoint */
+	list_for_each_entry (req, &ep->queue, queue) {
+		if (&req->req == _req)
+			break;
+	}
+	if (&req->req != _req) {
+		spin_unlock_irqrestore(&ep->udc->lock, flags);
+		return -EINVAL;
+	}
+
+	if (use_dma && ep->dma_channel && ep->queue.next == &req->queue) {
+		int channel = ep->dma_channel;
+
+		/* releasing the dma completion cancels the request,
+		 * reclaiming the channel restarts the queue
+		 */
+		dma_channel_release(ep);
+		dma_channel_claim(ep, channel);
+	} else 
+		done(ep, req, -ECONNRESET);
+	spin_unlock_irqrestore(&ep->udc->lock, flags);
+	return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int omap_ep_set_halt(struct usb_ep *_ep, int value)
+{
+	struct omap_ep	*ep = container_of(_ep, struct omap_ep, ep);
+	unsigned long	flags;
+	int		status = -EOPNOTSUPP;
+
+	spin_lock_irqsave(&ep->udc->lock, flags);
+
+	/* just use protocol stalls for ep0; real halts are annoying */
+	if (ep->bEndpointAddress == 0) {
+		if (!ep->udc->ep0_pending)
+			status = -EINVAL;
+		else if (value) {
+			if (ep->udc->ep0_set_config) {
+				WARN("error changing config?\n");
+				UDC_SYSCON2_REG = UDC_CLR_CFG;
+			}
+			UDC_SYSCON2_REG = UDC_STALL_CMD;
+			ep->udc->ep0_pending = 0;
+			status = 0;
+		} else /* NOP */
+			status = 0;
+
+	/* otherwise, all active non-ISO endpoints can halt */
+	} else if (ep->bmAttributes != USB_ENDPOINT_XFER_ISOC && ep->desc) {
+
+		/* IN endpoints must already be idle */
+		if ((ep->bEndpointAddress & USB_DIR_IN)
+				&& !list_empty(&ep->queue)) { 
+			status = -EAGAIN;
+			goto done;
+		}
+
+		if (value) {
+			int	channel;
+
+			if (use_dma && ep->dma_channel
+					&& !list_empty(&ep->queue)) {
+				channel = ep->dma_channel;
+				dma_channel_release(ep);
+			} else
+				channel = 0;
+
+			use_ep(ep, UDC_EP_SEL);
+			if (UDC_STAT_FLG_REG & UDC_NON_ISO_FIFO_EMPTY) {
+				UDC_CTRL_REG = UDC_SET_HALT;
+				status = 0;
+			} else
+				status = -EAGAIN;
+			deselect_ep();
+
+			if (channel)
+				dma_channel_claim(ep, channel);
+		} else {
+			use_ep(ep, 0);
+			UDC_CTRL_REG = UDC_RESET_EP;
+			ep->ackwait = 0;
+			if (!(ep->bEndpointAddress & USB_DIR_IN))
+				UDC_CTRL_REG = UDC_SET_FIFO_EN;
+		}
+	}
+done:
+	VDBG("%s %s halt stat %d\n", ep->ep.name,
+		value ? "set" : "clear", status);
+
+	spin_unlock_irqrestore(&ep->udc->lock, flags);
+	return status;
+}
+
+static struct usb_ep_ops omap_ep_ops = {
+	.enable		= omap_ep_enable,
+	.disable	= omap_ep_disable,
+
+	.alloc_request	= omap_alloc_request,
+	.free_request	= omap_free_request,
+
+	.alloc_buffer	= omap_alloc_buffer,
+	.free_buffer	= omap_free_buffer,
+
+	.queue		= omap_ep_queue,
+	.dequeue	= omap_ep_dequeue,
+
+	.set_halt	= omap_ep_set_halt,
+	// fifo_status ... report bytes in fifo
+	// fifo_flush ... flush fifo
+};
+
+/*-------------------------------------------------------------------------*/
+
+static int omap_get_frame(struct usb_gadget *gadget)
+{
+	u16	sof = UDC_SOF_REG;
+	return (sof & UDC_TS_OK) ? (sof & UDC_TS) : -EL2NSYNC;
+}
+
+static int omap_wakeup(struct usb_gadget *gadget)
+{
+	struct omap_udc	*udc;
+	unsigned long	flags;
+	int		retval = -EHOSTUNREACH;
+
+	udc = container_of(gadget, struct omap_udc, gadget);
+
+	spin_lock_irqsave(&udc->lock, flags);
+	if (udc->devstat & UDC_SUS) {
+		/* NOTE:  OTG spec erratum says that OTG devices may
+		 * issue wakeups without host enable.
+		 */
+		if (udc->devstat & (UDC_B_HNP_ENABLE|UDC_R_WK_OK)) {
+			DBG("remote wakeup...\n");
+			UDC_SYSCON2_REG = UDC_RMT_WKP;
+			retval = 0;
+		}
+
+	/* NOTE:  non-OTG systems may use SRP TOO... */
+	} else if (!(udc->devstat & UDC_ATT)) {
+		if (udc->transceiver)
+			retval = otg_start_srp(udc->transceiver);
+	}
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return retval;
+}
+
+static int
+omap_set_selfpowered(struct usb_gadget *gadget, int is_selfpowered)
+{
+	struct omap_udc	*udc;
+	unsigned long	flags;
+	u16		syscon1;
+
+	udc = container_of(gadget, struct omap_udc, gadget);
+	spin_lock_irqsave(&udc->lock, flags);
+	syscon1 = UDC_SYSCON1_REG;
+	if (is_selfpowered)
+		syscon1 |= UDC_SELF_PWR;
+	else
+		syscon1 &= ~UDC_SELF_PWR;
+	UDC_SYSCON1_REG = syscon1;
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return 0;
+}
+
+static int can_pullup(struct omap_udc *udc)
+{
+	return udc->driver && udc->softconnect && udc->vbus_active;
+}
+
+static void pullup_enable(struct omap_udc *udc)
+{
+	UDC_SYSCON1_REG |= UDC_PULLUP_EN;
+#ifndef CONFIG_USB_OTG
+	OTG_CTRL_REG |= OTG_BSESSVLD;
+#endif
+	UDC_IRQ_EN_REG = UDC_DS_CHG_IE;
+}
+
+static void pullup_disable(struct omap_udc *udc)
+{
+#ifndef CONFIG_USB_OTG
+	OTG_CTRL_REG &= ~OTG_BSESSVLD;
+#endif
+	UDC_IRQ_EN_REG = UDC_DS_CHG_IE;
+	UDC_SYSCON1_REG &= ~UDC_PULLUP_EN;
+}
+
+/*
+ * Called by whatever detects VBUS sessions:  external transceiver
+ * driver, or maybe GPIO0 VBUS IRQ.
+ */
+static int omap_vbus_session(struct usb_gadget *gadget, int is_active)
+{
+	struct omap_udc	*udc;
+	unsigned long	flags;
+
+	udc = container_of(gadget, struct omap_udc, gadget);
+	spin_lock_irqsave(&udc->lock, flags);
+	VDBG("VBUS %s\n", is_active ? "on" : "off");
+	udc->vbus_active = (is_active != 0);
+	if (can_pullup(udc))
+		pullup_enable(udc);
+	else
+		pullup_disable(udc);
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return 0;
+}
+
+static int omap_vbus_draw(struct usb_gadget *gadget, unsigned mA)
+{
+	struct omap_udc	*udc;
+
+	udc = container_of(gadget, struct omap_udc, gadget);
+	if (udc->transceiver)
+		return otg_set_power(udc->transceiver, mA);
+	return -EOPNOTSUPP;
+}
+
+static int omap_pullup(struct usb_gadget *gadget, int is_on)
+{
+	struct omap_udc	*udc;
+	unsigned long	flags;
+
+	udc = container_of(gadget, struct omap_udc, gadget);
+	spin_lock_irqsave(&udc->lock, flags);
+	udc->softconnect = (is_on != 0);
+	if (can_pullup(udc))
+		pullup_enable(udc);
+	else
+		pullup_disable(udc);
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return 0;
+}
+
+static struct usb_gadget_ops omap_gadget_ops = {
+	.get_frame		= omap_get_frame,
+	.wakeup			= omap_wakeup,
+	.set_selfpowered	= omap_set_selfpowered,
+	.vbus_session		= omap_vbus_session,
+	.vbus_draw		= omap_vbus_draw,
+	.pullup			= omap_pullup,
+};
+
+/*-------------------------------------------------------------------------*/
+
+/* dequeue ALL requests; caller holds udc->lock */
+static void nuke(struct omap_ep *ep, int status)
+{
+	struct omap_req	*req;
+
+	ep->stopped = 1;
+
+	if (use_dma && ep->dma_channel)
+		dma_channel_release(ep);
+
+	use_ep(ep, 0);
+	UDC_CTRL_REG = UDC_CLR_EP;
+	if (ep->bEndpointAddress && ep->bmAttributes != USB_ENDPOINT_XFER_ISOC)
+		UDC_CTRL_REG = UDC_SET_HALT;
+
+	while (!list_empty(&ep->queue)) {
+		req = list_entry(ep->queue.next, struct omap_req, queue);
+		done(ep, req, status);
+	}
+}
+
+/* caller holds udc->lock */
+static void udc_quiesce(struct omap_udc *udc)
+{
+	struct omap_ep	*ep;
+
+	udc->gadget.speed = USB_SPEED_UNKNOWN;
+	nuke(&udc->ep[0], -ESHUTDOWN);
+	list_for_each_entry (ep, &udc->gadget.ep_list, ep.ep_list)
+		nuke(ep, -ESHUTDOWN);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void update_otg(struct omap_udc *udc)
+{
+	u16	devstat;
+
+	if (!udc->gadget.is_otg)
+		return;
+
+	if (OTG_CTRL_REG & OTG_ID)
+		devstat = UDC_DEVSTAT_REG;
+	else
+		devstat = 0;
+
+	udc->gadget.b_hnp_enable = !!(devstat & UDC_B_HNP_ENABLE);
+	udc->gadget.a_hnp_support = !!(devstat & UDC_A_HNP_SUPPORT);
+	udc->gadget.a_alt_hnp_support = !!(devstat & UDC_A_ALT_HNP_SUPPORT);
+
+	/* Enable HNP early, avoiding races on suspend irq path.
+	 * ASSUMES OTG state machine B_BUS_REQ input is true.
+	 */
+	if (udc->gadget.b_hnp_enable)
+		OTG_CTRL_REG = (OTG_CTRL_REG | OTG_B_HNPEN | OTG_B_BUSREQ)
+				& ~OTG_PULLUP;
+}
+
+static void ep0_irq(struct omap_udc *udc, u16 irq_src)
+{
+	struct omap_ep	*ep0 = &udc->ep[0];
+	struct omap_req	*req = 0;
+
+	ep0->irqs++;
+
+	/* Clear any pending requests and then scrub any rx/tx state
+	 * before starting to handle the SETUP request.
+	 */
+	if (irq_src & UDC_SETUP)
+		nuke(ep0, 0);
+
+	/* IN/OUT packets mean we're in the DATA or STATUS stage.  
+	 * This driver uses only uses protocol stalls (ep0 never halts),
+	 * and if we got this far the gadget driver already had a
+	 * chance to stall.  Tries to be forgiving of host oddities.
+	 *
+	 * NOTE:  the last chance gadget drivers have to stall control
+	 * requests is during their request completion callback.
+	 */
+	if (!list_empty(&ep0->queue))
+		req = container_of(ep0->queue.next, struct omap_req, queue);
+
+	/* IN == TX to host */
+	if (irq_src & UDC_EP0_TX) {
+		int	stat;
+
+		UDC_IRQ_SRC_REG = UDC_EP0_TX;
+		UDC_EP_NUM_REG = UDC_EP_SEL|UDC_EP_DIR;
+		stat = UDC_STAT_FLG_REG;
+		if (stat & UDC_ACK) {
+			if (udc->ep0_in) {
+				/* write next IN packet from response,
+				 * or set up the status stage.
+				 */
+				if (req)
+					stat = write_fifo(ep0, req);
+				UDC_EP_NUM_REG = UDC_EP_DIR;
+				if (!req && udc->ep0_pending) {
+					UDC_EP_NUM_REG = UDC_EP_SEL;
+					UDC_CTRL_REG = UDC_CLR_EP;
+					UDC_CTRL_REG = UDC_SET_FIFO_EN;
+					UDC_EP_NUM_REG = 0;
+					udc->ep0_pending = 0;
+				} /* else:  6 wait states before it'll tx */
+			} else {
+				/* ack status stage of OUT transfer */
+				UDC_EP_NUM_REG = UDC_EP_DIR;
+				if (req)
+					done(ep0, req, 0);
+			}
+			req = 0;
+		} else if (stat & UDC_STALL) {
+			UDC_CTRL_REG = UDC_CLR_HALT;
+			UDC_EP_NUM_REG = UDC_EP_DIR;
+		} else {
+			UDC_EP_NUM_REG = UDC_EP_DIR;
+		}
+	}
+
+	/* OUT == RX from host */
+	if (irq_src & UDC_EP0_RX) {
+		int	stat;
+
+		UDC_IRQ_SRC_REG = UDC_EP0_RX;
+		UDC_EP_NUM_REG = UDC_EP_SEL;
+		stat = UDC_STAT_FLG_REG;
+		if (stat & UDC_ACK) {
+			if (!udc->ep0_in) {
+				stat = 0;
+				/* read next OUT packet of request, maybe
+				 * reactiviting the fifo; stall on errors.
+				 */
+				if (!req || (stat = read_fifo(ep0, req)) < 0) {
+					UDC_SYSCON2_REG = UDC_STALL_CMD;
+					udc->ep0_pending = 0;
+					stat = 0;
+				} else if (stat == 0)
+					UDC_CTRL_REG = UDC_SET_FIFO_EN;
+				UDC_EP_NUM_REG = 0;
+				
+				/* activate status stage */
+				if (stat == 1) {
+					done(ep0, req, 0);
+					/* that may have STALLed ep0... */
+					UDC_EP_NUM_REG = UDC_EP_SEL|UDC_EP_DIR;
+					UDC_CTRL_REG = UDC_CLR_EP;
+					UDC_CTRL_REG = UDC_SET_FIFO_EN;
+					UDC_EP_NUM_REG = UDC_EP_DIR;
+					udc->ep0_pending = 0;
+				}
+			} else {
+				/* ack status stage of IN transfer */
+				UDC_EP_NUM_REG = 0;
+				if (req)
+					done(ep0, req, 0);
+			}
+		} else if (stat & UDC_STALL) {
+			UDC_CTRL_REG = UDC_CLR_HALT;
+			UDC_EP_NUM_REG = 0;
+		} else {
+			UDC_EP_NUM_REG = 0;
+		}
+	}
+
+	/* SETUP starts all control transfers */
+	if (irq_src & UDC_SETUP) {
+		union u {
+			u16			word[4];
+			struct usb_ctrlrequest	r;
+		} u;
+		int			status = -EINVAL;
+		struct omap_ep		*ep;
+
+		/* read the (latest) SETUP message */
+		do {
+			UDC_EP_NUM_REG = UDC_SETUP_SEL;
+			/* two bytes at a time */
+			u.word[0] = UDC_DATA_REG;
+			u.word[1] = UDC_DATA_REG;
+			u.word[2] = UDC_DATA_REG;
+			u.word[3] = UDC_DATA_REG;
+			UDC_EP_NUM_REG = 0;
+		} while (UDC_IRQ_SRC_REG & UDC_SETUP);
+		le16_to_cpus (&u.r.wValue);
+		le16_to_cpus (&u.r.wIndex);
+		le16_to_cpus (&u.r.wLength);
+
+		/* Delegate almost all control requests to the gadget driver,
+		 * except for a handful of ch9 status/feature requests that
+		 * hardware doesn't autodecode _and_ the gadget API hides.
+		 */
+		udc->ep0_in = (u.r.bRequestType & USB_DIR_IN) != 0;
+		udc->ep0_set_config = 0;
+		udc->ep0_pending = 1;
+		ep0->stopped = 0;
+		ep0->ackwait = 0;
+		switch (u.r.bRequest) {
+		case USB_REQ_SET_CONFIGURATION:
+			/* udc needs to know when ep != 0 is valid */
+			if (u.r.bRequestType != USB_RECIP_DEVICE)
+				goto delegate;
+			if (u.r.wLength != 0)
+				goto do_stall;
+			udc->ep0_set_config = 1;
+			udc->ep0_reset_config = (u.r.wValue == 0);
+			VDBG("set config %d\n", u.r.wValue);
+
+			/* update udc NOW since gadget driver may start
+			 * queueing requests immediately; clear config
+			 * later if it fails the request.
+			 */
+			if (udc->ep0_reset_config)
+				UDC_SYSCON2_REG = UDC_CLR_CFG;
+			else
+				UDC_SYSCON2_REG = UDC_DEV_CFG;
+			update_otg(udc);
+			goto delegate;
+		case USB_REQ_CLEAR_FEATURE:
+			/* clear endpoint halt */
+			if (u.r.bRequestType != USB_RECIP_ENDPOINT)
+				goto delegate;
+			if (u.r.wValue != USB_ENDPOINT_HALT
+					|| u.r.wLength != 0)
+				goto do_stall;
+			ep = &udc->ep[u.r.wIndex & 0xf];
+			if (ep != ep0) {
+				if (u.r.wIndex & USB_DIR_IN)
+					ep += 16;
+				if (ep->bmAttributes == USB_ENDPOINT_XFER_ISOC
+						|| !ep->desc)
+					goto do_stall;
+				use_ep(ep, 0);
+				UDC_CTRL_REG = UDC_RESET_EP;
+				ep->ackwait = 0;
+				if (!(ep->bEndpointAddress & USB_DIR_IN))
+					UDC_CTRL_REG = UDC_SET_FIFO_EN;
+			}
+			VDBG("%s halt cleared by host\n", ep->name);
+			goto ep0out_status_stage;
+		case USB_REQ_SET_FEATURE:
+			/* set endpoint halt */
+			if (u.r.bRequestType != USB_RECIP_ENDPOINT)
+				goto delegate;
+			if (u.r.wValue != USB_ENDPOINT_HALT
+					|| u.r.wLength != 0)
+				goto do_stall;
+			ep = &udc->ep[u.r.wIndex & 0xf];
+			if (u.r.wIndex & USB_DIR_IN)
+				ep += 16;
+			if (ep->bmAttributes == USB_ENDPOINT_XFER_ISOC
+					|| ep == ep0 || !ep->desc)
+				goto do_stall;
+			if (use_dma && ep->has_dma) {
+				/* this has rude side-effects (aborts) and
+				 * can't really work if DMA-IN is active
+				 */
+				DBG("%s host set_halt, NYET \n", ep->name);
+				goto do_stall;
+			}
+			use_ep(ep, 0);
+			/* can't halt if fifo isn't empty... */
+			UDC_CTRL_REG = UDC_CLR_EP;
+			UDC_CTRL_REG = UDC_SET_HALT;
+			VDBG("%s halted by host\n", ep->name);
+ep0out_status_stage:
+			status = 0;
+			UDC_EP_NUM_REG = UDC_EP_SEL|UDC_EP_DIR;
+			UDC_CTRL_REG = UDC_CLR_EP;
+			UDC_CTRL_REG = UDC_SET_FIFO_EN;
+			UDC_EP_NUM_REG = UDC_EP_DIR;
+			udc->ep0_pending = 0;
+			break;
+		case USB_REQ_GET_STATUS:
+			/* return interface status.  if we were pedantic,
+			 * we'd detect non-existent interfaces, and stall.
+			 */
+			if (u.r.bRequestType
+					!= (USB_DIR_IN|USB_RECIP_INTERFACE))
+				goto delegate;
+			/* return two zero bytes */
+			UDC_EP_NUM_REG = UDC_EP_SEL|UDC_EP_DIR;
+			UDC_DATA_REG = 0;
+			UDC_CTRL_REG = UDC_SET_FIFO_EN;
+			UDC_EP_NUM_REG = UDC_EP_DIR;
+			status = 0;
+			VDBG("GET_STATUS, interface %d\n", u.r.wIndex);
+			/* next, status stage */
+			break;
+		default:
+delegate:
+			/* activate the ep0out fifo right away */
+			if (!udc->ep0_in && u.r.wLength) {
+				UDC_EP_NUM_REG = 0;
+				UDC_CTRL_REG = UDC_SET_FIFO_EN;
+			}
+
+			/* gadget drivers see class/vendor specific requests,
+			 * {SET,GET}_{INTERFACE,DESCRIPTOR,CONFIGURATION},
+			 * and more
+			 */
+			VDBG("SETUP %02x.%02x v%04x i%04x l%04x\n",
+				u.r.bRequestType, u.r.bRequest,
+				u.r.wValue, u.r.wIndex, u.r.wLength);
+
+			/* The gadget driver may return an error here,
+			 * causing an immediate protocol stall.
+			 *
+			 * Else it must issue a response, either queueing a
+			 * response buffer for the DATA stage, or halting ep0
+			 * (causing a protocol stall, not a real halt).  A
+			 * zero length buffer means no DATA stage.
+			 *
+			 * It's fine to issue that response after the setup()
+			 * call returns, and this IRQ was handled.
+			 */
+			udc->ep0_setup = 1;
+			spin_unlock(&udc->lock);
+			status = udc->driver->setup (&udc->gadget, &u.r);
+			spin_lock(&udc->lock);
+			udc->ep0_setup = 0;
+		}
+
+		if (status < 0) {
+do_stall:
+			VDBG("req %02x.%02x protocol STALL; stat %d\n",
+					u.r.bRequestType, u.r.bRequest, status);
+			if (udc->ep0_set_config) {
+				if (udc->ep0_reset_config)
+					WARN("error resetting config?\n");
+				else
+					UDC_SYSCON2_REG = UDC_CLR_CFG;
+			}
+			UDC_SYSCON2_REG = UDC_STALL_CMD;
+			udc->ep0_pending = 0;
+		}
+	}
+}
+
+/*-------------------------------------------------------------------------*/
+
+#define OTG_FLAGS (UDC_B_HNP_ENABLE|UDC_A_HNP_SUPPORT|UDC_A_ALT_HNP_SUPPORT)
+
+static void devstate_irq(struct omap_udc *udc, u16 irq_src)
+{
+	u16	devstat, change;
+
+	devstat = UDC_DEVSTAT_REG;
+	change = devstat ^ udc->devstat;
+	udc->devstat = devstat;
+
+	if (change & (UDC_USB_RESET|UDC_ATT)) {
+		udc_quiesce(udc);
+
+		if (change & UDC_ATT) {
+			/* driver for any external transceiver will
+			 * have called omap_vbus_session() already
+			 */
+			if (devstat & UDC_ATT) {
+				udc->gadget.speed = USB_SPEED_FULL;
+				VDBG("connect\n");
+				if (!udc->transceiver)
+					pullup_enable(udc);
+				// if (driver->connect) call it
+			} else if (udc->gadget.speed != USB_SPEED_UNKNOWN) {
+				udc->gadget.speed = USB_SPEED_UNKNOWN;
+				if (!udc->transceiver)
+					pullup_disable(udc);
+				DBG("disconnect, gadget %s\n",
+					udc->driver->driver.name);
+				if (udc->driver->disconnect) {
+					spin_unlock(&udc->lock);
+					udc->driver->disconnect(&udc->gadget);
+					spin_lock(&udc->lock);
+				}
+			}
+			change &= ~UDC_ATT;
+		}
+
+		if (change & UDC_USB_RESET) {
+			if (devstat & UDC_USB_RESET) {
+				VDBG("RESET=1\n");
+			} else {
+				udc->gadget.speed = USB_SPEED_FULL;
+				INFO("USB reset done, gadget %s\n",
+					udc->driver->driver.name);
+				/* ep0 traffic is legal from now on */
+				UDC_IRQ_EN_REG = UDC_DS_CHG_IE | UDC_EP0_IE;
+			}
+			change &= ~UDC_USB_RESET;
+		}
+	}
+	if (change & UDC_SUS) {
+		if (udc->gadget.speed != USB_SPEED_UNKNOWN) {
+			// FIXME tell isp1301 to suspend/resume (?)
+			if (devstat & UDC_SUS) {
+				VDBG("suspend\n");
+				update_otg(udc);
+				/* HNP could be under way already */
+				if (udc->gadget.speed == USB_SPEED_FULL
+						&& udc->driver->suspend) {
+					spin_unlock(&udc->lock);
+					udc->driver->suspend(&udc->gadget);
+					spin_lock(&udc->lock);
+				}
+			} else {
+				VDBG("resume\n");
+				if (udc->gadget.speed == USB_SPEED_FULL
+						&& udc->driver->resume) {
+					spin_unlock(&udc->lock);
+					udc->driver->resume(&udc->gadget);
+					spin_lock(&udc->lock);
+				}
+			}
+		}
+		change &= ~UDC_SUS;
+	}
+	if (change & OTG_FLAGS) {
+		update_otg(udc);
+		change &= ~OTG_FLAGS;
+	}
+
+	change &= ~(UDC_CFG|UDC_DEF|UDC_ADD);
+	if (change)
+		VDBG("devstat %03x, ignore change %03x\n",
+			devstat,  change);
+
+	UDC_IRQ_SRC_REG = UDC_DS_CHG;
+}
+
+static irqreturn_t
+omap_udc_irq(int irq, void *_udc, struct pt_regs *r)
+{
+	struct omap_udc	*udc = _udc;
+	u16		irq_src;
+	irqreturn_t	status = IRQ_NONE;
+	unsigned long	flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	irq_src = UDC_IRQ_SRC_REG;
+
+	/* Device state change (usb ch9 stuff) */
+	if (irq_src & UDC_DS_CHG) {
+		devstate_irq(_udc, irq_src);
+		status = IRQ_HANDLED;
+		irq_src &= ~UDC_DS_CHG;
+	}
+
+	/* EP0 control transfers */
+	if (irq_src & (UDC_EP0_RX|UDC_SETUP|UDC_EP0_TX)) {
+		ep0_irq(_udc, irq_src);
+		status = IRQ_HANDLED;
+		irq_src &= ~(UDC_EP0_RX|UDC_SETUP|UDC_EP0_TX);
+	}
+
+	/* DMA transfer completion */
+	if (use_dma && (irq_src & (UDC_TXN_DONE|UDC_RXN_CNT|UDC_RXN_EOT))) {
+		dma_irq(_udc, irq_src);
+		status = IRQ_HANDLED;
+		irq_src &= ~(UDC_TXN_DONE|UDC_RXN_CNT|UDC_RXN_EOT);
+	}
+
+	irq_src &= ~(UDC_SOF|UDC_EPN_TX|UDC_EPN_RX);
+	if (irq_src)
+		DBG("udc_irq, unhandled %03x\n", irq_src);
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	return status;
+}
+
+static irqreturn_t
+omap_udc_pio_irq(int irq, void *_dev, struct pt_regs *r)
+{
+	u16		epn_stat, irq_src;
+	irqreturn_t	status = IRQ_NONE;
+	struct omap_ep	*ep;
+	int		epnum;
+	struct omap_udc	*udc = _dev;
+	struct omap_req	*req;
+	unsigned long	flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	epn_stat = UDC_EPN_STAT_REG;
+	irq_src = UDC_IRQ_SRC_REG;
+
+	/* handle OUT first, to avoid some wasteful NAKs */
+	if (irq_src & UDC_EPN_RX) {
+		epnum = (epn_stat >> 8) & 0x0f;
+		UDC_IRQ_SRC_REG = UDC_EPN_RX;
+		status = IRQ_HANDLED;
+		ep = &udc->ep[epnum];
+		ep->irqs++;
+
+		if (!list_empty(&ep->queue)) {
+			UDC_EP_NUM_REG = epnum | UDC_EP_SEL;
+			if ((UDC_STAT_FLG_REG & UDC_ACK)) {
+				int stat;
+				req = container_of(ep->queue.next,
+						struct omap_req, queue);
+				stat = read_fifo(ep, req);
+				// FIXME double buffered PIO OUT should work
+			}
+			UDC_EP_NUM_REG = epnum;
+		}
+	}
+
+	/* then IN transfers */
+	if (irq_src & UDC_EPN_TX) {
+		epnum = epn_stat & 0x0f;
+		UDC_IRQ_SRC_REG = UDC_EPN_TX;
+		status = IRQ_HANDLED;
+		ep = &udc->ep[16 + epnum];
+		ep->irqs++;
+		ep->ackwait = 0;
+
+		if (!list_empty(&ep->queue)) {
+			UDC_EP_NUM_REG = epnum | UDC_EP_DIR | UDC_EP_SEL;
+			if ((UDC_STAT_FLG_REG & UDC_ACK)) {
+				req = container_of(ep->queue.next,
+						struct omap_req, queue);
+				(void) write_fifo(ep, req);
+			}
+			UDC_EP_NUM_REG = epnum | UDC_EP_DIR;
+			/* 6 wait states before it'll tx */
+		}
+	}
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return status;
+}
+
+#ifdef	USE_ISO
+static irqreturn_t
+omap_udc_iso_irq(int irq, void *_dev, struct pt_regs *r)
+{
+	struct omap_udc	*udc = _dev;
+	struct omap_ep	*ep;
+	int		pending = 0;
+	unsigned long	flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	/* handle all non-DMA ISO transfers */
+	list_for_each_entry (ep, &udc->iso, iso) {
+		u16		stat;
+		struct omap_req	*req;
+
+		if (ep->has_dma || list_empty(&ep->queue))
+			continue;
+		req = list_entry(ep->queue.next, struct omap_req, queue);
+
+		use_ep(ep, UDC_EP_SEL);
+		stat = UDC_STAT_FLG_REG;
+
+		/* NOTE: like the other controller drivers, this isn't
+		 * currently reporting lost or damaged frames.
+		 */
+		if (ep->bEndpointAddress & USB_DIR_IN) {
+			if (stat & UDC_MISS_IN)
+				/* done(ep, req, -EPROTO) */;
+			else
+				write_fifo(ep, req);
+		} else {
+			int	status = 0;
+
+			if (stat & UDC_NO_RXPACKET)
+				status = -EREMOTEIO;
+			else if (stat & UDC_ISO_ERR)
+				status = -EILSEQ;
+			else if (stat & UDC_DATA_FLUSH)
+				status = -ENOSR;
+
+			if (status)
+				/* done(ep, req, status) */;
+			else
+				read_fifo(ep, req);
+		}
+		deselect_ep();
+		/* 6 wait states before next EP */
+
+		ep->irqs++;
+		if (!list_empty(&ep->queue))
+			pending = 1;
+	}
+	if (!pending)
+		UDC_IRQ_EN_REG &= ~UDC_SOF_IE;
+	UDC_IRQ_SRC_REG = UDC_SOF;
+
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return IRQ_HANDLED;
+}
+#endif
+
+/*-------------------------------------------------------------------------*/
+
+static struct omap_udc *udc;
+
+int usb_gadget_register_driver (struct usb_gadget_driver *driver)
+{
+	int		status = -ENODEV;
+	struct omap_ep	*ep;
+	unsigned long	flags;
+
+	/* basic sanity tests */
+	if (!udc)
+		return -ENODEV;
+	if (!driver
+			// FIXME if otg, check:  driver->is_otg
+			|| driver->speed < USB_SPEED_FULL
+			|| !driver->bind
+			|| !driver->unbind
+			|| !driver->setup)
+		return -EINVAL;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	if (udc->driver) {
+		spin_unlock_irqrestore(&udc->lock, flags);
+		return -EBUSY;
+	}
+
+	/* reset state */
+	list_for_each_entry (ep, &udc->gadget.ep_list, ep.ep_list) {
+		ep->irqs = 0;
+		if (ep->bmAttributes == USB_ENDPOINT_XFER_ISOC)
+			continue;
+		use_ep(ep, 0);
+		UDC_CTRL_REG = UDC_SET_HALT;
+	}
+	udc->ep0_pending = 0;
+	udc->ep[0].irqs = 0;
+	udc->softconnect = 1;
+
+	/* hook up the driver */
+	driver->driver.bus = 0;
+	udc->driver = driver;
+	udc->gadget.dev.driver = &driver->driver;
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	status = driver->bind (&udc->gadget);
+	if (status) {
+		DBG("bind to %s --> %d\n", driver->driver.name, status);
+		udc->gadget.dev.driver = 0;
+		udc->driver = 0;
+		goto done;
+	}
+	DBG("bound to driver %s\n", driver->driver.name);
+
+	UDC_IRQ_SRC_REG = UDC_IRQ_SRC_MASK;
+
+	/* connect to bus through transceiver */
+	if (udc->transceiver) {
+		status = otg_set_peripheral(udc->transceiver, &udc->gadget);
+		if (status < 0) {
+			ERR("can't bind to transceiver\n");
+			driver->unbind (&udc->gadget);
+			udc->gadget.dev.driver = 0;
+			udc->driver = 0;
+			goto done;
+		}
+	} else {
+		if (can_pullup(udc))
+			pullup_enable (udc);
+		else
+			pullup_disable (udc);
+	}
+
+done:
+	return status;
+}
+EXPORT_SYMBOL(usb_gadget_register_driver);
+
+int usb_gadget_unregister_driver (struct usb_gadget_driver *driver)
+{
+	unsigned long	flags;
+	int		status = -ENODEV;
+
+	if (!udc)
+		return -ENODEV;
+	if (!driver || driver != udc->driver)
+		return -EINVAL;
+
+	if (udc->transceiver)
+		(void) otg_set_peripheral(udc->transceiver, 0);
+	else
+		pullup_disable(udc);
+
+	spin_lock_irqsave(&udc->lock, flags);
+	udc_quiesce(udc);
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	driver->unbind(&udc->gadget);
+	udc->gadget.dev.driver = 0;
+	udc->driver = 0;
+
+
+	DBG("unregistered driver '%s'\n", driver->driver.name);
+	return status;
+}
+EXPORT_SYMBOL(usb_gadget_unregister_driver);
+
+
+/*-------------------------------------------------------------------------*/
+
+#ifdef CONFIG_USB_OMAP_PROC
+
+#include <linux/seq_file.h>
+
+static const char proc_filename[] = "driver/udc";
+
+#define FOURBITS "%s%s%s%s"
+#define EIGHTBITS FOURBITS FOURBITS
+
+static void proc_ep_show(struct seq_file *s, struct omap_ep *ep)
+{
+	u16		stat_flg;
+	struct omap_req	*req;
+	char		buf[20];
+
+	use_ep(ep, 0);
+
+	if (use_dma && ep->has_dma)
+		snprintf(buf, sizeof buf, "(%cxdma%d lch%d) ",
+			(ep->bEndpointAddress & USB_DIR_IN) ? 't' : 'r',
+			ep->dma_channel - 1, ep->lch);
+	else
+		buf[0] = 0;
+
+	stat_flg = UDC_STAT_FLG_REG;
+	seq_printf(s,
+		"\n%s %sirqs %ld stat %04x " EIGHTBITS FOURBITS "%s\n",
+		ep->name, buf, ep->irqs, stat_flg,
+		(stat_flg & UDC_NO_RXPACKET) ? "no_rxpacket " : "",
+		(stat_flg & UDC_MISS_IN) ? "miss_in " : "",
+		(stat_flg & UDC_DATA_FLUSH) ? "data_flush " : "",
+		(stat_flg & UDC_ISO_ERR) ? "iso_err " : "",
+		(stat_flg & UDC_ISO_FIFO_EMPTY) ? "iso_fifo_empty " : "",
+		(stat_flg & UDC_ISO_FIFO_FULL) ? "iso_fifo_full " : "",
+		(stat_flg & UDC_EP_HALTED) ? "HALT " : "",
+		(stat_flg & UDC_STALL) ? "STALL " : "",
+		(stat_flg & UDC_NAK) ? "NAK " : "",
+		(stat_flg & UDC_ACK) ? "ACK " : "",
+		(stat_flg & UDC_FIFO_EN) ? "fifo_en " : "",
+		(stat_flg & UDC_NON_ISO_FIFO_EMPTY) ? "fifo_empty " : "",
+		(stat_flg & UDC_NON_ISO_FIFO_FULL) ? "fifo_full " : "");
+
+	if (list_empty (&ep->queue))
+		seq_printf(s, "\t(queue empty)\n");
+	else
+		list_for_each_entry (req, &ep->queue, queue)
+			seq_printf(s, "\treq %p len %d/%d buf %p\n",
+					&req->req, req->req.actual,
+					req->req.length, req->req.buf);
+}
+
+static char *trx_mode(unsigned m)
+{
+	switch (m) {
+	case 3:
+	case 0:		return "6wire";
+	case 1:		return "4wire";
+	case 2:		return "3wire";
+	default:	return "unknown";
+	}
+}
+
+static int proc_udc_show(struct seq_file *s, void *_)
+{
+	u32		tmp;
+	struct omap_ep	*ep;
+	unsigned long	flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+
+	seq_printf(s, "%s, version: " DRIVER_VERSION
+#ifdef	USE_ISO
+		" (iso)"
+#endif
+		"%s\n",
+		driver_desc,
+		use_dma ?  " (dma)" : "");
+
+	tmp = UDC_REV_REG & 0xff; 
+	seq_printf(s,
+		"UDC rev %d.%d, OTG rev %d.%d, fifo mode %d, gadget %s\n"
+		"hmc %d, transceiver %08x %s\n",
+		tmp >> 4, tmp & 0xf,
+		OTG_REV_REG >> 4, OTG_REV_REG & 0xf,
+		fifo_mode,
+		udc->driver ? udc->driver->driver.name : "(none)",
+		HMC, USB_TRANSCEIVER_CTRL_REG,
+		udc->transceiver ? udc->transceiver->label : "");
+
+	/* OTG controller registers */
+	tmp = OTG_SYSCON_1_REG;
+	seq_printf(s, "otg_syscon1 %08x usb2 %s, usb1 %s, usb0 %s,"
+			FOURBITS "\n", tmp,
+		trx_mode(USB2_TRX_MODE(tmp)),
+		trx_mode(USB1_TRX_MODE(tmp)),
+		trx_mode(USB0_TRX_MODE(tmp)),
+		(tmp & OTG_IDLE_EN) ? " !otg" : "",
+		(tmp & HST_IDLE_EN) ? " !host" : "",
+		(tmp & DEV_IDLE_EN) ? " !dev" : "",
+		(tmp & OTG_RESET_DONE) ? " reset_done" : " reset_active");
+	tmp = OTG_SYSCON_2_REG;
+	seq_printf(s, "otg_syscon2 %08x%s" EIGHTBITS
+			" b_ase_brst=%d hmc=%d\n", tmp,
+		(tmp & OTG_EN) ? " otg_en" : "",
+		(tmp & USBX_SYNCHRO) ? " synchro" : "",
+		// much more SRP stuff
+		(tmp & SRP_DATA) ? " srp_data" : "",
+		(tmp & SRP_VBUS) ? " srp_vbus" : "",
+		(tmp & OTG_PADEN) ? " otg_paden" : "",
+		(tmp & HMC_PADEN) ? " hmc_paden" : "",
+		(tmp & UHOST_EN) ? " uhost_en" : "",
+		(tmp & HMC_TLLSPEED) ? " tllspeed" : "",
+		(tmp & HMC_TLLATTACH) ? " tllattach" : "",
+		B_ASE_BRST(tmp),
+		OTG_HMC(tmp));
+	tmp = OTG_CTRL_REG;
+	seq_printf(s, "otg_ctrl    %06x" EIGHTBITS EIGHTBITS "%s\n", tmp,
+		(tmp & OTG_ASESSVLD) ? " asess" : "",
+		(tmp & OTG_BSESSEND) ? " bsess_end" : "",
+		(tmp & OTG_BSESSVLD) ? " bsess" : "",
+		(tmp & OTG_VBUSVLD) ? " vbus" : "",
+		(tmp & OTG_ID) ? " id" : "",
+		(tmp & OTG_DRIVER_SEL) ? " DEVICE" : " HOST",
+		(tmp & OTG_A_SETB_HNPEN) ? " a_setb_hnpen" : "",
+		(tmp & OTG_A_BUSREQ) ? " a_bus" : "",
+		(tmp & OTG_B_HNPEN) ? " b_hnpen" : "",
+		(tmp & OTG_B_BUSREQ) ? " b_bus" : "",
+		(tmp & OTG_BUSDROP) ? " busdrop" : "",
+		(tmp & OTG_PULLDOWN) ? " down" : "",
+		(tmp & OTG_PULLUP) ? " up" : "",
+		(tmp & OTG_DRV_VBUS) ? " drv" : "",
+		(tmp & OTG_PD_VBUS) ? " pd_vb" : "",
+		(tmp & OTG_PU_VBUS) ? " pu_vb" : "",
+		(tmp & OTG_PU_ID) ? " pu_id" : ""
+		);
+	tmp = OTG_IRQ_EN_REG;
+	seq_printf(s, "otg_irq_en  %04x" "\n", tmp);
+	tmp = OTG_IRQ_SRC_REG;
+	seq_printf(s, "otg_irq_src %04x" "\n", tmp);
+	tmp = OTG_OUTCTRL_REG;
+	seq_printf(s, "otg_outctrl %04x" "\n", tmp);
+	tmp = OTG_TEST_REG;
+	seq_printf(s, "otg_test    %04x" "\n", tmp);
+
+	tmp = UDC_SYSCON1_REG;
+	seq_printf(s, "\nsyscon1     %04x" EIGHTBITS "\n", tmp,
+		(tmp & UDC_CFG_LOCK) ? " cfg_lock" : "",
+		(tmp & UDC_DATA_ENDIAN) ? " data_endian" : "",
+		(tmp & UDC_DMA_ENDIAN) ? " dma_endian" : "",
+		(tmp & UDC_NAK_EN) ? " nak" : "",
+		(tmp & UDC_AUTODECODE_DIS) ? " autodecode_dis" : "",
+		(tmp & UDC_SELF_PWR) ? " self_pwr" : "",
+		(tmp & UDC_SOFF_DIS) ? " soff_dis" : "",
+		(tmp & UDC_PULLUP_EN) ? " PULLUP" : "");
+	// syscon2 is write-only
+
+	/* UDC controller registers */
+	if (!(tmp & UDC_PULLUP_EN)) {
+		seq_printf(s, "(suspended)\n");
+		spin_unlock_irqrestore(&udc->lock, flags);
+		return 0;
+	}
+
+	tmp = UDC_DEVSTAT_REG;
+	seq_printf(s, "devstat     %04x" EIGHTBITS "%s%s\n", tmp,
+		(tmp & UDC_B_HNP_ENABLE) ? " b_hnp" : "",
+		(tmp & UDC_A_HNP_SUPPORT) ? " a_hnp" : "",
+		(tmp & UDC_A_ALT_HNP_SUPPORT) ? " a_alt_hnp" : "",
+		(tmp & UDC_R_WK_OK) ? " r_wk_ok" : "",
+		(tmp & UDC_USB_RESET) ? " usb_reset" : "",
+		(tmp & UDC_SUS) ? " SUS" : "",
+		(tmp & UDC_CFG) ? " CFG" : "",
+		(tmp & UDC_ADD) ? " ADD" : "",
+		(tmp & UDC_DEF) ? " DEF" : "",
+		(tmp & UDC_ATT) ? " ATT" : "");
+	seq_printf(s, "sof         %04x\n", UDC_SOF_REG);
+	tmp = UDC_IRQ_EN_REG;
+	seq_printf(s, "irq_en      %04x" FOURBITS "%s\n", tmp,
+		(tmp & UDC_SOF_IE) ? " sof" : "",
+		(tmp & UDC_EPN_RX_IE) ? " epn_rx" : "",
+		(tmp & UDC_EPN_TX_IE) ? " epn_tx" : "",
+		(tmp & UDC_DS_CHG_IE) ? " ds_chg" : "",
+		(tmp & UDC_EP0_IE) ? " ep0" : "");
+	tmp = UDC_IRQ_SRC_REG;
+	seq_printf(s, "irq_src     %04x" EIGHTBITS "%s%s\n", tmp,
+		(tmp & UDC_TXN_DONE) ? " txn_done" : "",
+		(tmp & UDC_RXN_CNT) ? " rxn_cnt" : "",
+		(tmp & UDC_RXN_EOT) ? " rxn_eot" : "",
+		(tmp & UDC_SOF) ? " sof" : "",
+		(tmp & UDC_EPN_RX) ? " epn_rx" : "",
+		(tmp & UDC_EPN_TX) ? " epn_tx" : "",
+		(tmp & UDC_DS_CHG) ? " ds_chg" : "",
+		(tmp & UDC_SETUP) ? " setup" : "",
+		(tmp & UDC_EP0_RX) ? " ep0out" : "",
+		(tmp & UDC_EP0_TX) ? " ep0in" : "");
+	if (use_dma) {
+		unsigned i;
+
+		tmp = UDC_DMA_IRQ_EN_REG;
+		seq_printf(s, "dma_irq_en  %04x%s" EIGHTBITS "\n", tmp,
+			(tmp & UDC_TX_DONE_IE(3)) ? " tx2_done" : "",
+			(tmp & UDC_RX_CNT_IE(3)) ? " rx2_cnt" : "",
+			(tmp & UDC_RX_EOT_IE(3)) ? " rx2_eot" : "",
+
+			(tmp & UDC_TX_DONE_IE(2)) ? " tx1_done" : "",
+			(tmp & UDC_RX_CNT_IE(2)) ? " rx1_cnt" : "",
+			(tmp & UDC_RX_EOT_IE(2)) ? " rx1_eot" : "",
+
+			(tmp & UDC_TX_DONE_IE(1)) ? " tx0_done" : "",
+			(tmp & UDC_RX_CNT_IE(1)) ? " rx0_cnt" : "",
+			(tmp & UDC_RX_EOT_IE(1)) ? " rx0_eot" : "");
+
+		tmp = UDC_RXDMA_CFG_REG;
+		seq_printf(s, "rxdma_cfg   %04x\n", tmp);
+		if (tmp) {
+			for (i = 0; i < 3; i++) {
+				if ((tmp & (0x0f << (i * 4))) == 0)
+					continue;
+				seq_printf(s, "rxdma[%d]    %04x\n", i,
+						UDC_RXDMA_REG(i + 1));
+			}
+		}
+		tmp = UDC_TXDMA_CFG_REG;
+		seq_printf(s, "txdma_cfg   %04x\n", tmp);
+		if (tmp) {
+			for (i = 0; i < 3; i++) {
+				if (!(tmp & (0x0f << (i * 4))))
+					continue;
+				seq_printf(s, "txdma[%d]    %04x\n", i,
+						UDC_TXDMA_REG(i + 1));
+			}
+		}
+	}
+
+	tmp = UDC_DEVSTAT_REG;
+	if (tmp & UDC_ATT) {
+		proc_ep_show(s, &udc->ep[0]);
+		if (tmp & UDC_ADD) {
+			list_for_each_entry (ep, &udc->gadget.ep_list,
+					ep.ep_list) {
+				if (ep->desc)
+					proc_ep_show(s, ep);
+			}
+		}
+	}
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return 0;
+}
+
+static int proc_udc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, proc_udc_show, 0);
+}
+
+static struct file_operations proc_ops = {
+	.open		= proc_udc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static void create_proc_file(void)
+{
+	struct proc_dir_entry *pde;
+
+	pde = create_proc_entry (proc_filename, 0, NULL);
+	if (pde)
+		pde->proc_fops = &proc_ops;
+}
+
+static void remove_proc_file(void)
+{
+	remove_proc_entry(proc_filename, 0);
+}
+
+#else
+
+static inline void create_proc_file(void) {}
+static inline void remove_proc_file(void) {}
+
+#endif
+
+/*-------------------------------------------------------------------------*/
+
+/* Before this controller can enumerate, we need to pick an endpoint
+ * configuration, or "fifo_mode"  That involves allocating 2KB of packet
+ * buffer space among the endpoints we'll be operating.
+ */
+static unsigned __init
+omap_ep_setup(char *name, u8 addr, u8 type,
+		unsigned buf, unsigned maxp, int dbuf)
+{
+	struct omap_ep	*ep;
+	u16		epn_rxtx = 0;
+
+	/* OUT endpoints first, then IN */
+	ep = &udc->ep[addr & 0xf];
+	if (addr & USB_DIR_IN)
+		ep += 16;
+
+	/* in case of ep init table bugs */
+	BUG_ON(ep->name[0]);
+
+	/* chip setup ... bit values are same for IN, OUT */
+	if (type == USB_ENDPOINT_XFER_ISOC) {
+		switch (maxp) {
+		case 8:		epn_rxtx = 0 << 12; break;
+		case 16:	epn_rxtx = 1 << 12; break;
+		case 32:	epn_rxtx = 2 << 12; break;
+		case 64:	epn_rxtx = 3 << 12; break;
+		case 128:	epn_rxtx = 4 << 12; break;
+		case 256:	epn_rxtx = 5 << 12; break;
+		case 512:	epn_rxtx = 6 << 12; break;
+		default:	BUG();
+		}
+		epn_rxtx |= UDC_EPN_RX_ISO;
+		dbuf = 1;
+	} else {
+		/* pio-out could potentially double-buffer,
+		 * as can (should!) DMA-IN
+		 */
+		if (!use_dma || (addr & USB_DIR_IN))
+			dbuf = 0;
+
+		switch (maxp) {
+		case 8:		epn_rxtx = 0 << 12; break;
+		case 16:	epn_rxtx = 1 << 12; break;
+		case 32:	epn_rxtx = 2 << 12; break;
+		case 64:	epn_rxtx = 3 << 12; break;
+		default:	BUG();
+		}
+		if (dbuf && addr)
+			epn_rxtx |= UDC_EPN_RX_DB;
+	}
+	if (addr)
+		epn_rxtx |= UDC_EPN_RX_VALID;
+	BUG_ON(buf & 0x07);
+	epn_rxtx |= buf >> 3;
+
+	DBG("%s addr %02x rxtx %04x maxp %d%s buf %d\n",
+		name, addr, epn_rxtx, maxp, dbuf ? "x2" : "", buf);
+
+	if (addr & USB_DIR_IN)
+		UDC_EP_TX_REG(addr & 0xf) = epn_rxtx;
+	else
+		UDC_EP_RX_REG(addr) = epn_rxtx;
+
+	/* next endpoint's buffer starts after this one's */
+	buf += maxp;
+	if (dbuf)
+		buf += maxp;
+	BUG_ON(buf > 2048);
+
+	/* set up driver data structures */
+	BUG_ON(strlen(name) >= sizeof ep->name);
+	strlcpy(ep->name, name, sizeof ep->name);
+	INIT_LIST_HEAD(&ep->queue);
+	INIT_LIST_HEAD(&ep->iso);
+	ep->bEndpointAddress = addr;
+	ep->bmAttributes = type;
+	ep->double_buf = dbuf;
+	ep->udc = udc; 
+
+	ep->ep.name = ep->name;
+	ep->ep.ops = &omap_ep_ops;
+	ep->ep.maxpacket = ep->maxpacket = maxp;
+	list_add_tail (&ep->ep.ep_list, &udc->gadget.ep_list);
+
+	return buf;
+}
+
+static void omap_udc_release(struct device *dev)
+{
+	complete(udc->done);
+	kfree (udc);
+	udc = 0;
+}
+
+static int __init
+omap_udc_setup(struct platform_device *odev, struct otg_transceiver *xceiv)
+{
+	unsigned	tmp, buf;
+
+	/* abolish any previous hardware state */
+	UDC_SYSCON1_REG = 0;
+	UDC_IRQ_EN_REG = 0;
+	UDC_IRQ_SRC_REG = UDC_IRQ_SRC_MASK;
+	UDC_DMA_IRQ_EN_REG = 0;
+	UDC_RXDMA_CFG_REG = 0;
+	UDC_TXDMA_CFG_REG = 0;
+
+	/* UDC_PULLUP_EN gates the chip clock */
+	// OTG_SYSCON_1_REG |= DEV_IDLE_EN;
+
+	udc = kmalloc (sizeof *udc, SLAB_KERNEL);
+	if (!udc)
+		return -ENOMEM;
+
+	memset(udc, 0, sizeof *udc);
+	spin_lock_init (&udc->lock);
+
+	udc->gadget.ops = &omap_gadget_ops;
+	udc->gadget.ep0 = &udc->ep[0].ep;
+	INIT_LIST_HEAD(&udc->gadget.ep_list);
+	INIT_LIST_HEAD(&udc->iso);
+	udc->gadget.speed = USB_SPEED_UNKNOWN;
+	udc->gadget.name = driver_name;
+
+	device_initialize(&udc->gadget.dev);
+	strcpy (udc->gadget.dev.bus_id, "gadget");
+	udc->gadget.dev.release = omap_udc_release;
+	udc->gadget.dev.parent = &odev->dev;
+	if (use_dma)
+		udc->gadget.dev.dma_mask = odev->dev.dma_mask;
+
+	udc->transceiver = xceiv;
+
+	/* ep0 is special; put it right after the SETUP buffer */
+	buf = omap_ep_setup("ep0", 0, USB_ENDPOINT_XFER_CONTROL,
+			8 /* after SETUP */, 64 /* maxpacket */, 0);
+	list_del_init(&udc->ep[0].ep.ep_list);
+
+	/* initially disable all non-ep0 endpoints */
+	for (tmp = 1; tmp < 15; tmp++) {
+		UDC_EP_RX_REG(tmp) = 0;
+		UDC_EP_TX_REG(tmp) = 0;
+	}
+
+#define OMAP_BULK_EP(name,addr) \
+	buf = omap_ep_setup(name "-bulk", addr, \
+			USB_ENDPOINT_XFER_BULK, buf, 64, 1);
+#define OMAP_INT_EP(name,addr, maxp) \
+	buf = omap_ep_setup(name "-int", addr, \
+			USB_ENDPOINT_XFER_INT, buf, maxp, 0);
+#define OMAP_ISO_EP(name,addr, maxp) \
+	buf = omap_ep_setup(name "-iso", addr, \
+			USB_ENDPOINT_XFER_ISOC, buf, maxp, 1);
+
+	switch (fifo_mode) {
+	case 0:
+		OMAP_BULK_EP("ep1in",  USB_DIR_IN  | 1);
+		OMAP_BULK_EP("ep2out", USB_DIR_OUT | 2);
+		OMAP_INT_EP("ep3in",   USB_DIR_IN  | 3, 16);
+		break;
+	case 1:
+		OMAP_BULK_EP("ep1in",  USB_DIR_IN  | 1);
+		OMAP_BULK_EP("ep2out", USB_DIR_OUT | 2);
+		OMAP_BULK_EP("ep3in",  USB_DIR_IN  | 3);
+		OMAP_BULK_EP("ep4out", USB_DIR_OUT | 4);
+
+		OMAP_BULK_EP("ep5in",  USB_DIR_IN  | 5);
+		OMAP_BULK_EP("ep5out", USB_DIR_OUT | 5);
+		OMAP_BULK_EP("ep6in",  USB_DIR_IN  | 6);
+		OMAP_BULK_EP("ep6out", USB_DIR_OUT | 6);
+
+		OMAP_BULK_EP("ep7in",  USB_DIR_IN  | 7);
+		OMAP_BULK_EP("ep7out", USB_DIR_OUT | 7);
+		OMAP_BULK_EP("ep8in",  USB_DIR_IN  | 8);
+		OMAP_BULK_EP("ep8out", USB_DIR_OUT | 8);
+
+		OMAP_INT_EP("ep9in",   USB_DIR_IN  | 9, 16);
+		OMAP_INT_EP("ep10out", USB_DIR_IN  | 10, 16);
+		OMAP_INT_EP("ep11in",  USB_DIR_IN  | 9, 16);
+		OMAP_INT_EP("ep12out", USB_DIR_IN  | 10, 16);
+		break;
+
+#ifdef	USE_ISO
+	case 2:			/* mixed iso/bulk */
+		OMAP_ISO_EP("ep1in",   USB_DIR_IN  | 1, 256);
+		OMAP_ISO_EP("ep2out",  USB_DIR_OUT | 2, 256);
+		OMAP_ISO_EP("ep3in",   USB_DIR_IN  | 3, 128);
+		OMAP_ISO_EP("ep4out",  USB_DIR_OUT | 4, 128);
+
+		OMAP_INT_EP("ep5in",   USB_DIR_IN  | 5, 16);
+
+		OMAP_BULK_EP("ep6in",  USB_DIR_IN  | 6);
+		OMAP_BULK_EP("ep7out", USB_DIR_OUT | 7);
+		OMAP_INT_EP("ep8in",   USB_DIR_IN  | 8, 16);
+		break;
+	case 3:			/* mixed bulk/iso */
+		OMAP_BULK_EP("ep1in",  USB_DIR_IN  | 1);
+		OMAP_BULK_EP("ep2out", USB_DIR_OUT | 2);
+		OMAP_INT_EP("ep3in",   USB_DIR_IN  | 3, 16);
+
+		OMAP_BULK_EP("ep4in",  USB_DIR_IN  | 4);
+		OMAP_BULK_EP("ep5out", USB_DIR_OUT | 5);
+		OMAP_INT_EP("ep6in",   USB_DIR_IN  | 6, 16);
+
+		OMAP_ISO_EP("ep7in",   USB_DIR_IN  | 7, 256);
+		OMAP_ISO_EP("ep8out",  USB_DIR_OUT | 8, 256);
+		OMAP_INT_EP("ep9in",   USB_DIR_IN  | 9, 16);
+		break;
+#endif
+
+	/* add more modes as needed */
+
+	default:
+		ERR("unsupported fifo_mode #%d\n", fifo_mode);
+		return -ENODEV;
+	}
+	UDC_SYSCON1_REG = UDC_CFG_LOCK|UDC_SELF_PWR;
+	INFO("fifo mode %d, %d bytes not used\n", fifo_mode, 2048 - buf);
+	return 0;
+}
+
+static int __init omap_udc_probe(struct device *dev)
+{
+	struct platform_device	*odev = to_platform_device(dev);
+	int			status = -ENODEV;
+	int			hmc;
+	struct otg_transceiver	*xceiv = 0;
+	const char		*type = 0;
+	struct omap_usb_config	*config = dev->platform_data;
+
+	/* NOTE:  "knows" the order of the resources! */
+	if (!request_mem_region(odev->resource[0].start, 
+			odev->resource[0].end - odev->resource[0].start + 1,
+			driver_name)) {
+		DBG("request_mem_region failed\n");
+		return -EBUSY;
+	}
+
+	INFO("OMAP UDC rev %d.%d, OTG rev %d.%d, %s receptacle\n",
+		UDC_REV_REG >> 4, UDC_REV_REG & 0xf,
+		OTG_REV_REG >> 4, OTG_REV_REG & 0xf,
+		config->otg ? "Mini-AB" : "B/Mini-B");
+
+	/* use the mode given to us by board init code */
+	hmc = HMC;
+	switch (hmc) {
+	case 3:
+	case 11:
+	case 19:
+	case 25:
+		xceiv = otg_get_transceiver();
+		if (!xceiv) {
+			DBG("external transceiver not registered!\n");
+			goto cleanup0;
+		}
+		type = xceiv->label;
+		break;
+	case 0:			/* POWERUP DEFAULT == 0 */
+	case 4:
+	case 12:
+	case 20:
+		type = "INTEGRATED";
+		break;
+	case 21:			/* internal loopback */
+		type = "(loopback)";
+		break;
+	case 14:			/* transceiverless */
+		type = "(none)";
+		break;
+
+	default:
+		ERR("unrecognized UDC HMC mode %d\n", hmc);
+		return -ENODEV;
+	}
+	INFO("hmc mode %d, transceiver %s\n", hmc, type);
+
+	/* a "gadget" abstracts/virtualizes the controller */
+	status = omap_udc_setup(odev, xceiv);
+	if (status) {
+		goto cleanup0;
+	}
+	xceiv = 0;
+	// "udc" is now valid
+	pullup_disable(udc);
+	udc->gadget.is_otg = (config->otg != 0);
+
+	/* USB general purpose IRQ:  ep0, state changes, dma, etc */
+	status = request_irq(odev->resource[1].start, omap_udc_irq,
+			SA_SAMPLE_RANDOM, driver_name, udc);
+	if (status != 0) {
+		ERR( "can't get irq %ld, err %d\n",
+			odev->resource[1].start, status);
+		goto cleanup1;
+	}
+
+	/* USB "non-iso" IRQ (PIO for all but ep0) */
+	status = request_irq(odev->resource[2].start, omap_udc_pio_irq,
+			SA_SAMPLE_RANDOM, "omap_udc pio", udc);
+	if (status != 0) {
+		ERR( "can't get irq %ld, err %d\n",
+			odev->resource[2].start, status);
+		goto cleanup2;
+	}
+#ifdef	USE_ISO
+	status = request_irq(odev->resource[3].start, omap_udc_iso_irq,
+			SA_INTERRUPT, "omap_udc iso", udc);
+	if (status != 0) {
+		ERR("can't get irq %ld, err %d\n",
+			odev->resource[3].start, status);
+		goto cleanup3;
+	}
+#endif
+
+	create_proc_file();
+	device_add(&udc->gadget.dev);
+	return 0;
+
+#ifdef	USE_ISO
+cleanup3:
+	free_irq(odev->resource[2].start, udc);
+#endif
+
+cleanup2:
+	free_irq(odev->resource[1].start, udc);
+
+cleanup1:
+	kfree (udc);
+	udc = 0;
+
+cleanup0:
+	if (xceiv)
+		put_device(xceiv->dev);
+	release_mem_region(odev->resource[0].start,
+			odev->resource[0].end - odev->resource[0].start + 1);
+	return status;
+}
+
+static int __exit omap_udc_remove(struct device *dev)
+{
+	struct platform_device	*odev = to_platform_device(dev);
+	DECLARE_COMPLETION(done);
+
+	if (!udc)
+		return -ENODEV;
+
+	udc->done = &done;
+
+	pullup_disable(udc);
+	if (udc->transceiver) {
+		put_device(udc->transceiver->dev);
+		udc->transceiver = 0;
+	}
+	UDC_SYSCON1_REG = 0;
+
+	remove_proc_file();
+
+#ifdef	USE_ISO
+	free_irq(odev->resource[3].start, udc);
+#endif
+	free_irq(odev->resource[2].start, udc);
+	free_irq(odev->resource[1].start, udc);
+
+	release_mem_region(odev->resource[0].start,
+			odev->resource[0].end - odev->resource[0].start + 1);
+
+	device_unregister(&udc->gadget.dev);
+	wait_for_completion(&done);
+
+	return 0;
+}
+
+/* suspend/resume/wakeup from sysfs (echo > power/state) */
+
+static int omap_udc_suspend(struct device *dev, u32 state, u32 level)
+{
+	if (level != 0)
+		return 0;
+
+	DBG("suspend, state %d\n", state);
+	omap_pullup(&udc->gadget, 0);
+	udc->gadget.dev.power.power_state = 3;
+	udc->gadget.dev.parent->power.power_state = 3;
+	return 0;
+}
+
+static int omap_udc_resume(struct device *dev, u32 level)
+{
+	if (level != 0)
+		return 0;
+
+	DBG("resume + wakeup/SRP\n");
+	udc->gadget.dev.parent->power.power_state = 0;
+	udc->gadget.dev.power.power_state = 0;
+	omap_pullup(&udc->gadget, 1);
+
+	/* maybe the host would enumerate us if we nudged it */
+	msleep(100);
+	return omap_wakeup(&udc->gadget);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static struct device_driver udc_driver = {
+	.name		= (char *) driver_name,
+	.bus		= &platform_bus_type,
+	.probe		= omap_udc_probe,
+	.remove		= __exit_p(omap_udc_remove),
+	.suspend	= omap_udc_suspend,
+	.resume		= omap_udc_resume,
+};
+
+static int __init udc_init(void)
+{
+	/* should work on many OMAP systems with at most minor changes,
+	 * but the 1510 doesn't have an OTG controller.
+	 */
+	if (cpu_is_omap1510()) {
+		DBG("no OMAP1510 support yet\n");
+		return -ENODEV;
+	}
+	INFO("%s, version: " DRIVER_VERSION "%s\n", driver_desc,
+		use_dma ?  " (dma)" : "");
+	return driver_register(&udc_driver);
+}
+module_init(udc_init);
+
+static void __exit udc_exit(void)
+{
+	driver_unregister(&udc_driver);
+}
+module_exit(udc_exit);
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+

drivers/usb/gadget/omap_udc.h

+/*
+ * omap_udc.h -- for omap 3.2 udc, with OTG support
+ *
+ * 2004 (C) Texas Instruments, Inc.
+ * 2004 (C) David Brownell
+ */
+
+/*
+ * USB device/endpoint management registers
+ */
+#define UDC_REG(offset)              __REG16(UDC_BASE + (offset))
+
+#define	UDC_REV_REG			UDC_REG(0x0)	/* Revision */
+#define	UDC_EP_NUM_REG			UDC_REG(0x4)	/* Which endpoint */
+#	define	UDC_SETUP_SEL		(1 << 6)
+#	define	UDC_EP_SEL		(1 << 5)
+#	define	UDC_EP_DIR		(1 << 4)
+	/* low 4 bits for endpoint number */
+#define	UDC_DATA_REG			UDC_REG(0x08)	/* Endpoint FIFO */
+#define	UDC_CTRL_REG			UDC_REG(0x0C)	/* Endpoint control */
+#	define	UDC_CLR_HALT		(1 << 7)
+#	define	UDC_SET_HALT		(1 << 6)
+#	define	UDC_SET_FIFO_EN		(1 << 2)
+#	define	UDC_CLR_EP		(1 << 1)
+#	define	UDC_RESET_EP		(1 << 0)
+#define	UDC_STAT_FLG_REG		UDC_REG(0x10)	/* Endpoint status */
+#	define	UDC_NO_RXPACKET		(1 << 15)
+#	define	UDC_MISS_IN		(1 << 14)
+#	define	UDC_DATA_FLUSH		(1 << 13)
+#	define	UDC_ISO_ERR		(1 << 12)
+#	define	UDC_ISO_FIFO_EMPTY	(1 << 9)
+#	define	UDC_ISO_FIFO_FULL	(1 << 8)
+#	define	UDC_EP_HALTED		(1 << 6)
+#	define	UDC_STALL		(1 << 5)
+#	define	UDC_NAK			(1 << 4)
+#	define	UDC_ACK			(1 << 3)
+#	define	UDC_FIFO_EN		(1 << 2)
+#	define	UDC_NON_ISO_FIFO_EMPTY	(1 << 1)
+#	define	UDC_NON_ISO_FIFO_FULL	(1 << 0)
+#define	UDC_RXFSTAT_REG			UDC_REG(0x14)	/* OUT bytecount */
+#define	UDC_SYSCON1_REG			UDC_REG(0x18)	/* System config 1 */
+#	define	UDC_CFG_LOCK		(1 << 8)
+#	define	UDC_DATA_ENDIAN		(1 << 7)
+#	define	UDC_DMA_ENDIAN		(1 << 6)
+#	define	UDC_NAK_EN		(1 << 4)
+#	define	UDC_AUTODECODE_DIS	(1 << 3)
+#	define	UDC_SELF_PWR		(1 << 2)
+#	define	UDC_SOFF_DIS		(1 << 1)
+#	define	UDC_PULLUP_EN		(1 << 0)
+#define	UDC_SYSCON2_REG			UDC_REG(0x1C)	/* System config 2 */
+#	define	UDC_RMT_WKP		(1 << 6)
+#	define	UDC_STALL_CMD		(1 << 5)
+#	define	UDC_DEV_CFG		(1 << 3)
+#	define	UDC_CLR_CFG		(1 << 2)
+#define	UDC_DEVSTAT_REG			UDC_REG(0x20)	/* Device status */
+#	define	UDC_B_HNP_ENABLE	(1 << 9)
+#	define	UDC_A_HNP_SUPPORT	(1 << 8)
+#	define	UDC_A_ALT_HNP_SUPPORT	(1 << 7)
+#	define	UDC_R_WK_OK		(1 << 6)
+#	define	UDC_USB_RESET		(1 << 5)
+#	define	UDC_SUS			(1 << 4)
+#	define	UDC_CFG			(1 << 3)
+#	define	UDC_ADD			(1 << 2)
+#	define	UDC_DEF			(1 << 1)
+#	define	UDC_ATT			(1 << 0)
+#define	UDC_SOF_REG			UDC_REG(0x24)	/* Start of frame */
+#	define	UDC_FT_LOCK		(1 << 12)
+#	define	UDC_TS_OK		(1 << 11)
+#	define	UDC_TS			0x03ff
+#define	UDC_IRQ_EN_REG			UDC_REG(0x28)	/* Interrupt enable */
+#	define	UDC_SOF_IE		(1 << 7)
+#	define	UDC_EPN_RX_IE		(1 << 5)
+#	define	UDC_EPN_TX_IE		(1 << 4)
+#	define	UDC_DS_CHG_IE		(1 << 3)
+#	define	UDC_EP0_IE		(1 << 0)
+#define	UDC_DMA_IRQ_EN_REG		UDC_REG(0x2C)	/* DMA irq enable */
+	/* rx/tx dma channels numbered 1-3 not 0-2 */
+#	define	UDC_TX_DONE_IE(n)	(1 << (4 * (n) - 2))
+#	define	UDC_RX_CNT_IE(n)	(1 << (4 * (n) - 3))
+#	define	UDC_RX_EOT_IE(n)	(1 << (4 * (n) - 4))
+#define	UDC_IRQ_SRC_REG			UDC_REG(0x30)	/* Interrupt source */
+#	define	UDC_TXN_DONE		(1 << 10)
+#	define	UDC_RXN_CNT		(1 << 9)
+#	define	UDC_RXN_EOT		(1 << 8)
+#	define	UDC_SOF			(1 << 7)
+#	define	UDC_EPN_RX		(1 << 5)
+#	define	UDC_EPN_TX		(1 << 4)
+#	define	UDC_DS_CHG		(1 << 3)
+#	define	UDC_SETUP		(1 << 2)
+#	define	UDC_EP0_RX		(1 << 1)
+#	define	UDC_EP0_TX		(1 << 0)
+#	define	UDC_IRQ_SRC_MASK	0x7bf
+#define	UDC_EPN_STAT_REG		UDC_REG(0x34)	/* EP irq status */
+#define	UDC_DMAN_STAT_REG		UDC_REG(0x38)	/* DMA irq status */
+#	define	UDC_DMA_RX_SB		(1 << 12)
+#	define	UDC_DMA_RX_SRC(x)	(((x)>>8) & 0xf)
+#	define	UDC_DMA_TX_SRC(x)	(((x)>>0) & 0xf)
+
+
+/* DMA configuration registers:  up to three channels in each direction.  */
+#define	UDC_RXDMA_CFG_REG		UDC_REG(0x40)	/* 3 eps for RX DMA */
+#define	UDC_TXDMA_CFG_REG		UDC_REG(0x44)	/* 3 eps for TX DMA */
+#define	UDC_DATA_DMA_REG		UDC_REG(0x48)	/* rx/tx fifo addr */
+
+/* rx/tx dma control, numbering channels 1-3 not 0-2 */
+#define	UDC_TXDMA_REG(chan)		UDC_REG(0x50 - 4 + 4 * (chan))
+#	define UDC_TXN_EOT		(1 << 15)	/* bytes vs packets */
+#	define UDC_TXN_START		(1 << 14)	/* start transfer */
+#	define UDC_TXN_TSC		0x03ff		/* units in xfer */
+#define	UDC_RXDMA_REG(chan)		UDC_REG(0x60 - 4 + 4 * (chan))
+#	define UDC_RXN_STOP		(1 << 15)	/* enable EOT irq */
+#	define UDC_RXN_TC		0x00ff		/* packets in xfer */
+
+
+/*
+ * Endpoint configuration registers (used before CFG_LOCK is set)
+ * UDC_EP_TX_REG(0) is unused
+ */
+#define	UDC_EP_RX_REG(endpoint)		UDC_REG(0x80 + (endpoint)*4)
+#	define	UDC_EPN_RX_VALID	(1 << 15)
+#	define	UDC_EPN_RX_DB		(1 << 14)
+	/* buffer size in bits 13, 12 */
+#	define	UDC_EPN_RX_ISO		(1 << 11)
+	/* buffer pointer in low 11 bits */
+#define	UDC_EP_TX_REG(endpoint)		UDC_REG(0xc0 + (endpoint)*4)
+	/* same bitfields as in RX_REG */
+
+/*-------------------------------------------------------------------------*/
+
+struct omap_req {
+	struct usb_request		req;
+	struct list_head		queue;
+	unsigned			dma_bytes;
+	unsigned			mapped:1;
+};
+
+struct omap_ep {
+	struct usb_ep			ep;
+	struct list_head		queue;
+	unsigned long			irqs;
+	struct list_head		iso;
+	const struct usb_endpoint_descriptor	*desc;
+	char				name[14];
+	u16				maxpacket;
+	u8				bEndpointAddress;
+	u8				bmAttributes;
+	unsigned			double_buf:1;
+	unsigned			stopped:1;
+	unsigned			ackwait:1;
+	unsigned			has_dma:1;
+	u8				dma_channel;
+	int				lch;
+	struct omap_udc			*udc;
+};
+
+struct omap_udc {
+	struct usb_gadget		gadget;
+	struct usb_gadget_driver	*driver;
+	spinlock_t			lock;
+	struct omap_ep			ep[32];
+	u16				devstat;
+	struct otg_transceiver		*transceiver;
+	struct list_head		iso;
+	unsigned			softconnect:1;
+	unsigned			vbus_active:1;
+	unsigned			ep0_pending:1;
+	unsigned			ep0_in:1;
+	unsigned			ep0_set_config:1;
+	unsigned			ep0_reset_config:1;
+	unsigned			ep0_setup:1;
+	unsigned			hmc:6;
+
+	struct completion		*done;
+};
+
+/*-------------------------------------------------------------------------*/
+
+#ifdef DEBUG
+#define DBG(stuff...)		printk(KERN_DEBUG "udc: " stuff)
+#else
+#define DBG(stuff...)		do{}while(0)
+#endif
+
+#ifdef VERBOSE
+#    define VDBG		DBG
+#else
+#    define VDBG(stuff...)	do{}while(0)
+#endif
+
+#define ERR(stuff...)		printk(KERN_ERR "udc: " stuff)
+#define WARN(stuff...)		printk(KERN_WARNING "udc: " stuff)
+#define INFO(stuff...)		printk(KERN_INFO "udc: " stuff)
+
+/*-------------------------------------------------------------------------*/
+
+// #define	HMC_1510	((MOD_CONF_CTRL_0_REG >> 1) & 0x3f)
+#define	HMC_1610	(OTG_SYSCON_2_REG & 0x3f)
+#define	HMC		 HMC_1610
+