Move the new USB stack into its new home.

1 files changed, 1653 insertions, 0 deletions

diff --git a/sys/dev/usb/usb_compat_linux.c b/sys/dev/usb/usb_compat_linux.c
new file mode 100644
index 0000000..a544a98
--- /dev/null
+++ b/sys/dev/usb/usb_compat_linux.c
@@ -0,0 +1,1653 @@
+/* $FreeBSD$ */
+/*-
+ * Copyright (c) 2007 Luigi Rizzo - Universita` di Pisa. All rights reserved.
+ * Copyright (c) 2007 Hans Petter Selasky. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <dev/usb/usb_defs.h>
+#include <dev/usb/usb_mfunc.h>
+#include <dev/usb/usb.h>
+#include <dev/usb/usb_error.h>
+#include <dev/usb/usb_ioctl.h>
+
+#define	USB_DEBUG_VAR usb2_debug
+
+#include <dev/usb/usb_core.h>
+#include <dev/usb/usb_compat_linux.h>
+#include <dev/usb/usb_process.h>
+#include <dev/usb/usb_device.h>
+#include <dev/usb/usb_util.h>
+#include <dev/usb/usb_busdma.h>
+#include <dev/usb/usb_transfer.h>
+#include <dev/usb/usb_parse.h>
+#include <dev/usb/usb_hub.h>
+#include <dev/usb/usb_request.h>
+#include <dev/usb/usb_debug.h>
+
+struct usb_linux_softc {
+	LIST_ENTRY(usb_linux_softc) sc_attached_list;
+
+	device_t sc_fbsd_dev;
+	struct usb2_device *sc_fbsd_udev;
+	struct usb_interface *sc_ui;
+	struct usb_driver *sc_udrv;
+};
+
+/* prototypes */
+static device_probe_t usb_linux_probe;
+static device_attach_t usb_linux_attach;
+static device_detach_t usb_linux_detach;
+static device_suspend_t usb_linux_suspend;
+static device_resume_t usb_linux_resume;
+static device_shutdown_t usb_linux_shutdown;
+
+static usb2_callback_t usb_linux_isoc_callback;
+static usb2_callback_t usb_linux_non_isoc_callback;
+
+static usb_complete_t usb_linux_wait_complete;
+
+static uint16_t	usb_max_isoc_frames(struct usb_device *);
+static int	usb_start_wait_urb(struct urb *, uint32_t, uint16_t *);
+static const struct usb_device_id *usb_linux_lookup_id(
+		    const struct usb_device_id *, struct usb2_attach_arg *);
+static struct	usb_driver *usb_linux_get_usb_driver(struct usb_linux_softc *);
+static struct	usb_device *usb_linux_create_usb_device(struct usb2_device *,
+		    device_t);
+static void	usb_linux_cleanup_interface(struct usb_device *,
+		    struct usb_interface *);
+static void	usb_linux_complete(struct usb2_xfer *);
+static int	usb_unlink_urb_sub(struct urb *, uint8_t);
+
+/*------------------------------------------------------------------------*
+ * FreeBSD USB interface
+ *------------------------------------------------------------------------*/
+
+static LIST_HEAD(, usb_linux_softc) usb_linux_attached_list;
+static LIST_HEAD(, usb_driver) usb_linux_driver_list;
+
+static device_method_t usb_linux_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe, usb_linux_probe),
+	DEVMETHOD(device_attach, usb_linux_attach),
+	DEVMETHOD(device_detach, usb_linux_detach),
+	DEVMETHOD(device_suspend, usb_linux_suspend),
+	DEVMETHOD(device_resume, usb_linux_resume),
+	DEVMETHOD(device_shutdown, usb_linux_shutdown),
+
+	{0, 0}
+};
+
+static driver_t usb_linux_driver = {
+	.name = "usb_linux",
+	.methods = usb_linux_methods,
+	.size = sizeof(struct usb_linux_softc),
+};
+
+static devclass_t usb_linux_devclass;
+
+DRIVER_MODULE(usb_linux, ushub, usb_linux_driver, usb_linux_devclass, NULL, 0);
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_lookup_id
+ *
+ * This functions takes an array of "struct usb_device_id" and tries
+ * to match the entries with the information in "struct usb2_attach_arg".
+ * If it finds a match the matching entry will be returned.
+ * Else "NULL" will be returned.
+ *------------------------------------------------------------------------*/
+static const struct usb_device_id *
+usb_linux_lookup_id(const struct usb_device_id *id, struct usb2_attach_arg *uaa)
+{
+	if (id == NULL) {
+		goto done;
+	}
+	/*
+	 * Keep on matching array entries until we find one with
+	 * "match_flags" equal to zero, which indicates the end of the
+	 * array:
+	 */
+	for (; id->match_flags; id++) {
+
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
+		    (id->idVendor != uaa->info.idVendor)) {
+			continue;
+		}
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
+		    (id->idProduct != uaa->info.idProduct)) {
+			continue;
+		}
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
+		    (id->bcdDevice_lo > uaa->info.bcdDevice)) {
+			continue;
+		}
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
+		    (id->bcdDevice_hi < uaa->info.bcdDevice)) {
+			continue;
+		}
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
+		    (id->bDeviceClass != uaa->info.bDeviceClass)) {
+			continue;
+		}
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
+		    (id->bDeviceSubClass != uaa->info.bDeviceSubClass)) {
+			continue;
+		}
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
+		    (id->bDeviceProtocol != uaa->info.bDeviceProtocol)) {
+			continue;
+		}
+		if ((uaa->info.bDeviceClass == 0xFF) &&
+		    !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
+		    (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
+		    USB_DEVICE_ID_MATCH_INT_SUBCLASS |
+		    USB_DEVICE_ID_MATCH_INT_PROTOCOL))) {
+			continue;
+		}
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
+		    (id->bInterfaceClass != uaa->info.bInterfaceClass)) {
+			continue;
+		}
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
+		    (id->bInterfaceSubClass != uaa->info.bInterfaceSubClass)) {
+			continue;
+		}
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
+		    (id->bInterfaceProtocol != uaa->info.bInterfaceProtocol)) {
+			continue;
+		}
+		/* we found a match! */
+		return (id);
+	}
+
+done:
+	return (NULL);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_probe
+ *
+ * This function is the FreeBSD probe callback. It is called from the
+ * FreeBSD USB stack through the "device_probe_and_attach()" function.
+ *------------------------------------------------------------------------*/
+static int
+usb_linux_probe(device_t dev)
+{
+	struct usb2_attach_arg *uaa = device_get_ivars(dev);
+	struct usb_driver *udrv;
+	int err = ENXIO;
+
+	if (uaa->usb2_mode != USB_MODE_HOST) {
+		return (ENXIO);
+	}
+	mtx_lock(&Giant);
+	LIST_FOREACH(udrv, &usb_linux_driver_list, linux_driver_list) {
+		if (usb_linux_lookup_id(udrv->id_table, uaa)) {
+			err = 0;
+			break;
+		}
+	}
+	mtx_unlock(&Giant);
+
+	return (err);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_get_usb_driver
+ *
+ * This function returns the pointer to the "struct usb_driver" where
+ * the Linux USB device driver "struct usb_device_id" match was found.
+ * We apply a lock before reading out the pointer to avoid races.
+ *------------------------------------------------------------------------*/
+static struct usb_driver *
+usb_linux_get_usb_driver(struct usb_linux_softc *sc)
+{
+	struct usb_driver *udrv;
+
+	mtx_lock(&Giant);
+	udrv = sc->sc_udrv;
+	mtx_unlock(&Giant);
+	return (udrv);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_attach
+ *
+ * This function is the FreeBSD attach callback. It is called from the
+ * FreeBSD USB stack through the "device_probe_and_attach()" function.
+ * This function is called when "usb_linux_probe()" returns zero.
+ *------------------------------------------------------------------------*/
+static int
+usb_linux_attach(device_t dev)
+{
+	struct usb2_attach_arg *uaa = device_get_ivars(dev);
+	struct usb_linux_softc *sc = device_get_softc(dev);
+	struct usb_driver *udrv;
+	struct usb_device *p_dev;
+	const struct usb_device_id *id = NULL;
+
+	mtx_lock(&Giant);
+	LIST_FOREACH(udrv, &usb_linux_driver_list, linux_driver_list) {
+		id = usb_linux_lookup_id(udrv->id_table, uaa);
+		if (id)
+			break;
+	}
+	mtx_unlock(&Giant);
+
+	if (id == NULL) {
+		return (ENXIO);
+	}
+	/*
+	 * Save some memory and only create the Linux compat structure when
+	 * needed:
+	 */
+	p_dev = uaa->device->linux_dev;
+	if (p_dev == NULL) {
+		p_dev = usb_linux_create_usb_device(uaa->device, dev);
+		if (p_dev == NULL) {
+			return (ENOMEM);
+		}
+		uaa->device->linux_dev = p_dev;
+	}
+	device_set_usb2_desc(dev);
+
+	sc->sc_fbsd_udev = uaa->device;
+	sc->sc_fbsd_dev = dev;
+	sc->sc_udrv = udrv;
+	sc->sc_ui = usb_ifnum_to_if(p_dev, uaa->info.bIfaceNum);
+	if (sc->sc_ui == NULL) {
+		return (EINVAL);
+	}
+	if (udrv->probe) {
+		if ((udrv->probe) (sc->sc_ui, id)) {
+			return (ENXIO);
+		}
+	}
+	mtx_lock(&Giant);
+	LIST_INSERT_HEAD(&usb_linux_attached_list, sc, sc_attached_list);
+	mtx_unlock(&Giant);
+
+	/* success */
+	return (0);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_detach
+ *
+ * This function is the FreeBSD detach callback. It is called from the
+ * FreeBSD USB stack through the "device_detach()" function.
+ *------------------------------------------------------------------------*/
+static int
+usb_linux_detach(device_t dev)
+{
+	struct usb_linux_softc *sc = device_get_softc(dev);
+	struct usb_driver *udrv = NULL;
+
+	mtx_lock(&Giant);
+	if (sc->sc_attached_list.le_prev) {
+		LIST_REMOVE(sc, sc_attached_list);
+		sc->sc_attached_list.le_prev = NULL;
+		udrv = sc->sc_udrv;
+		sc->sc_udrv = NULL;
+	}
+	mtx_unlock(&Giant);
+
+	if (udrv && udrv->disconnect) {
+		(udrv->disconnect) (sc->sc_ui);
+	}
+	/*
+	 * Make sure that we free all FreeBSD USB transfers belonging to
+	 * this Linux "usb_interface", hence they will most likely not be
+	 * needed any more.
+	 */
+	usb_linux_cleanup_interface(sc->sc_fbsd_udev->linux_dev, sc->sc_ui);
+	return (0);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_suspend
+ *
+ * This function is the FreeBSD suspend callback. Usually it does nothing.
+ *------------------------------------------------------------------------*/
+static int
+usb_linux_suspend(device_t dev)
+{
+	struct usb_linux_softc *sc = device_get_softc(dev);
+	struct usb_driver *udrv = usb_linux_get_usb_driver(sc);
+	int err;
+
+	if (udrv && udrv->suspend) {
+		err = (udrv->suspend) (sc->sc_ui, 0);
+	}
+	return (0);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_resume
+ *
+ * This function is the FreeBSD resume callback. Usually it does nothing.
+ *------------------------------------------------------------------------*/
+static int
+usb_linux_resume(device_t dev)
+{
+	struct usb_linux_softc *sc = device_get_softc(dev);
+	struct usb_driver *udrv = usb_linux_get_usb_driver(sc);
+	int err;
+
+	if (udrv && udrv->resume) {
+		err = (udrv->resume) (sc->sc_ui);
+	}
+	return (0);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_shutdown
+ *
+ * This function is the FreeBSD shutdown callback. Usually it does nothing.
+ *------------------------------------------------------------------------*/
+static int
+usb_linux_shutdown(device_t dev)
+{
+	struct usb_linux_softc *sc = device_get_softc(dev);
+	struct usb_driver *udrv = usb_linux_get_usb_driver(sc);
+
+	if (udrv && udrv->shutdown) {
+		(udrv->shutdown) (sc->sc_ui);
+	}
+	return (0);
+}
+
+/*------------------------------------------------------------------------*
+ * Linux emulation layer
+ *------------------------------------------------------------------------*/
+
+/*------------------------------------------------------------------------*
+ *	usb_max_isoc_frames
+ *
+ * The following function returns the maximum number of isochronous
+ * frames that we support per URB. It is not part of the Linux USB API.
+ *------------------------------------------------------------------------*/
+static uint16_t
+usb_max_isoc_frames(struct usb_device *dev)
+{
+	;				/* indent fix */
+	switch (usb2_get_speed(dev->bsd_udev)) {
+	case USB_SPEED_LOW:
+	case USB_SPEED_FULL:
+		return (USB_MAX_FULL_SPEED_ISOC_FRAMES);
+	default:
+		return (USB_MAX_HIGH_SPEED_ISOC_FRAMES);
+	}
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_submit_urb
+ *
+ * This function is used to queue an URB after that it has been
+ * initialized. If it returns non-zero, it means that the URB was not
+ * queued.
+ *------------------------------------------------------------------------*/
+int
+usb_submit_urb(struct urb *urb, uint16_t mem_flags)
+{
+	struct usb_host_endpoint *uhe;
+
+	if (urb == NULL) {
+		return (-EINVAL);
+	}
+	mtx_assert(&Giant, MA_OWNED);
+
+	if (urb->pipe == NULL) {
+		return (-EINVAL);
+	}
+	uhe = urb->pipe;
+
+	/*
+	 * Check that we have got a FreeBSD USB transfer that will dequeue
+	 * the URB structure and do the real transfer. If there are no USB
+	 * transfers, then we return an error.
+	 */
+	if (uhe->bsd_xfer[0] ||
+	    uhe->bsd_xfer[1]) {
+		/* we are ready! */
+
+		TAILQ_INSERT_HEAD(&uhe->bsd_urb_list, urb, bsd_urb_list);
+
+		urb->status = -EINPROGRESS;
+
+		usb2_transfer_start(uhe->bsd_xfer[0]);
+		usb2_transfer_start(uhe->bsd_xfer[1]);
+	} else {
+		/* no pipes have been setup yet! */
+		urb->status = -EINVAL;
+		return (-EINVAL);
+	}
+	return (0);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_unlink_urb
+ *
+ * This function is used to stop an URB after that it is been
+ * submitted, but before the "complete" callback has been called. On
+ *------------------------------------------------------------------------*/
+int
+usb_unlink_urb(struct urb *urb)
+{
+	return (usb_unlink_urb_sub(urb, 0));
+}
+
+static void
+usb_unlink_bsd(struct usb2_xfer *xfer,
+    struct urb *urb, uint8_t drain)
+{
+	if (xfer &&
+	    usb2_transfer_pending(xfer) &&
+	    (xfer->priv_fifo == (void *)urb)) {
+		if (drain) {
+			mtx_unlock(&Giant);
+			usb2_transfer_drain(xfer);
+			mtx_lock(&Giant);
+		} else {
+			usb2_transfer_stop(xfer);
+		}
+		usb2_transfer_start(xfer);
+	}
+}
+
+static int
+usb_unlink_urb_sub(struct urb *urb, uint8_t drain)
+{
+	struct usb_host_endpoint *uhe;
+	uint16_t x;
+
+	if (urb == NULL) {
+		return (-EINVAL);
+	}
+	mtx_assert(&Giant, MA_OWNED);
+
+	if (urb->pipe == NULL) {
+		return (-EINVAL);
+	}
+	uhe = urb->pipe;
+
+	if (urb->bsd_urb_list.tqe_prev) {
+
+		/* not started yet, just remove it from the queue */
+		TAILQ_REMOVE(&uhe->bsd_urb_list, urb, bsd_urb_list);
+		urb->bsd_urb_list.tqe_prev = NULL;
+		urb->status = -ECONNRESET;
+		urb->actual_length = 0;
+
+		for (x = 0; x < urb->number_of_packets; x++) {
+			urb->iso_frame_desc[x].actual_length = 0;
+		}
+
+		if (urb->complete) {
+			(urb->complete) (urb);
+		}
+	} else {
+
+		/*
+		 * If the URB is not on the URB list, then check if one of
+		 * the FreeBSD USB transfer are processing the current URB.
+		 * If so, re-start that transfer, which will lead to the
+		 * termination of that URB:
+		 */
+		usb_unlink_bsd(uhe->bsd_xfer[0], urb, drain);
+		usb_unlink_bsd(uhe->bsd_xfer[1], urb, drain);
+	}
+	return (0);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_clear_halt
+ *
+ * This function must always be used to clear the stall. Stall is when
+ * an USB endpoint returns a stall message to the USB host controller.
+ * Until the stall is cleared, no data can be transferred.
+ *------------------------------------------------------------------------*/
+int
+usb_clear_halt(struct usb_device *dev, struct usb_host_endpoint *uhe)
+{
+	struct usb2_config cfg[1];
+	struct usb2_pipe *pipe;
+	uint8_t type;
+	uint8_t addr;
+
+	if (uhe == NULL)
+		return (-EINVAL);
+
+	type = uhe->desc.bmAttributes & UE_XFERTYPE;
+	addr = uhe->desc.bEndpointAddress;
+
+	bzero(cfg, sizeof(cfg));
+
+	cfg[0].type = type;
+	cfg[0].endpoint = addr & UE_ADDR;
+	cfg[0].direction = addr & (UE_DIR_OUT | UE_DIR_IN);
+
+	pipe = usb2_get_pipe(dev->bsd_udev, uhe->bsd_iface_index, cfg);
+	if (pipe == NULL)
+		return (-EINVAL);
+
+	usb2_clear_data_toggle(dev->bsd_udev, pipe);
+
+	return (usb_control_msg(dev, &dev->ep0,
+	    UR_CLEAR_FEATURE, UT_WRITE_ENDPOINT,
+	    UF_ENDPOINT_HALT, addr, NULL, 0, 1000));
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_start_wait_urb
+ *
+ * This is an internal function that is used to perform synchronous
+ * Linux USB transfers.
+ *------------------------------------------------------------------------*/
+static int
+usb_start_wait_urb(struct urb *urb, uint32_t timeout, uint16_t *p_actlen)
+{
+	int err;
+
+	/* you must have a timeout! */
+	if (timeout == 0) {
+		timeout = 1;
+	}
+	urb->complete = &usb_linux_wait_complete;
+	urb->timeout = timeout;
+	urb->transfer_flags |= URB_WAIT_WAKEUP;
+	urb->transfer_flags &= ~URB_IS_SLEEPING;
+
+	err = usb_submit_urb(urb, 0);
+	if (err)
+		goto done;
+
+	/*
+	 * the URB might have completed before we get here, so check that by
+	 * using some flags!
+	 */
+	while (urb->transfer_flags & URB_WAIT_WAKEUP) {
+		urb->transfer_flags |= URB_IS_SLEEPING;
+		usb2_cv_wait(&urb->cv_wait, &Giant);
+		urb->transfer_flags &= ~URB_IS_SLEEPING;
+	}
+
+	err = urb->status;
+
+done:
+	if (err) {
+		*p_actlen = 0;
+	} else {
+		*p_actlen = urb->actual_length;
+	}
+	return (err);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_control_msg
+ *
+ * The following function performs a control transfer sequence one any
+ * control, bulk or interrupt endpoint, specified by "uhe". A control
+ * transfer means that you transfer an 8-byte header first followed by
+ * a data-phase as indicated by the 8-byte header. The "timeout" is
+ * given in milliseconds.
+ *
+ * Return values:
+ *   0: Success
+ * < 0: Failure
+ * > 0: Acutal length
+ *------------------------------------------------------------------------*/
+int
+usb_control_msg(struct usb_device *dev, struct usb_host_endpoint *uhe,
+    uint8_t request, uint8_t requesttype,
+    uint16_t value, uint16_t index, void *data,
+    uint16_t size, uint32_t timeout)
+{
+	struct usb2_device_request req;
+	struct urb *urb;
+	int err;
+	uint16_t actlen;
+	uint8_t type;
+	uint8_t addr;
+
+	req.bmRequestType = requesttype;
+	req.bRequest = request;
+	USETW(req.wValue, value);
+	USETW(req.wIndex, index);
+	USETW(req.wLength, size);
+
+	if (uhe == NULL) {
+		return (-EINVAL);
+	}
+	type = (uhe->desc.bmAttributes & UE_XFERTYPE);
+	addr = (uhe->desc.bEndpointAddress & UE_ADDR);
+
+	if (type != UE_CONTROL) {
+		return (-EINVAL);
+	}
+	if (addr == 0) {
+		/*
+		 * The FreeBSD USB stack supports standard control
+		 * transfers on control endpoint zero:
+		 */
+		err = usb2_do_request_flags(dev->bsd_udev,
+		    &Giant, &req, data, USB_SHORT_XFER_OK,
+		    &actlen, timeout);
+		if (err) {
+			err = -EPIPE;
+		} else {
+			err = actlen;
+		}
+		return (err);
+	}
+	if (dev->bsd_udev->flags.usb2_mode != USB_MODE_HOST) {
+		/* not supported */
+		return (-EINVAL);
+	}
+	err = usb_setup_endpoint(dev, uhe, 1 /* dummy */ );
+
+	/*
+	 * NOTE: we need to allocate real memory here so that we don't
+	 * transfer data to/from the stack!
+	 *
+	 * 0xFFFF is a FreeBSD specific magic value.
+	 */
+	urb = usb_alloc_urb(0xFFFF, size);
+	if (urb == NULL)
+		return (-ENOMEM);
+
+	urb->dev = dev;
+	urb->pipe = uhe;
+
+	bcopy(&req, urb->setup_packet, sizeof(req));
+
+	if (size && (!(req.bmRequestType & UT_READ))) {
+		/* move the data to a real buffer */
+		bcopy(data, USB_ADD_BYTES(urb->setup_packet,
+		    sizeof(req)), size);
+	}
+	err = usb_start_wait_urb(urb, timeout, &actlen);
+
+	if (req.bmRequestType & UT_READ) {
+		if (actlen) {
+			bcopy(USB_ADD_BYTES(urb->setup_packet,
+			    sizeof(req)), data, actlen);
+		}
+	}
+	usb_free_urb(urb);
+
+	if (err == 0) {
+		err = actlen;
+	}
+	return (err);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_set_interface
+ *
+ * The following function will select which alternate setting of an
+ * USB interface you plan to use. By default alternate setting with
+ * index zero is selected. Note that "iface_no" is not the interface
+ * index, but rather the value of "bInterfaceNumber".
+ *------------------------------------------------------------------------*/
+int
+usb_set_interface(struct usb_device *dev, uint8_t iface_no, uint8_t alt_index)
+{
+	struct usb_interface *p_ui = usb_ifnum_to_if(dev, iface_no);
+	int err;
+
+	if (p_ui == NULL)
+		return (-EINVAL);
+	if (alt_index >= p_ui->num_altsetting)
+		return (-EINVAL);
+	usb_linux_cleanup_interface(dev, p_ui);
+	err = -usb2_set_alt_interface_index(dev->bsd_udev,
+	    p_ui->bsd_iface_index, alt_index);
+	if (err == 0) {
+		p_ui->cur_altsetting = p_ui->altsetting + alt_index;
+	}
+	return (err);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_setup_endpoint
+ *
+ * The following function is an extension to the Linux USB API that
+ * allows you to set a maximum buffer size for a given USB endpoint.
+ * The maximum buffer size is per URB. If you don't call this function
+ * to set a maximum buffer size, the endpoint will not be functional.
+ * Note that for isochronous endpoints the maximum buffer size must be
+ * a non-zero dummy, hence this function will base the maximum buffer
+ * size on "wMaxPacketSize".
+ *------------------------------------------------------------------------*/
+int
+usb_setup_endpoint(struct usb_device *dev,
+    struct usb_host_endpoint *uhe, uint32_t bufsize)
+{
+	struct usb2_config cfg[2];
+	uint8_t type = uhe->desc.bmAttributes & UE_XFERTYPE;
+	uint8_t addr = uhe->desc.bEndpointAddress;
+
+	if (uhe->fbsd_buf_size == bufsize) {
+		/* optimize */
+		return (0);
+	}
+	usb2_transfer_unsetup(uhe->bsd_xfer, 2);
+
+	uhe->fbsd_buf_size = bufsize;
+
+	if (bufsize == 0) {
+		return (0);
+	}
+	bzero(cfg, sizeof(cfg));
+
+	if (type == UE_ISOCHRONOUS) {
+
+		/*
+		 * Isochronous transfers are special in that they don't fit
+		 * into the BULK/INTR/CONTROL transfer model.
+		 */
+
+		cfg[0].type = type;
+		cfg[0].endpoint = addr & UE_ADDR;
+		cfg[0].direction = addr & (UE_DIR_OUT | UE_DIR_IN);
+		cfg[0].mh.callback = &usb_linux_isoc_callback;
+		cfg[0].mh.bufsize = 0;	/* use wMaxPacketSize */
+		cfg[0].mh.frames = usb_max_isoc_frames(dev);
+		cfg[0].mh.flags.proxy_buffer = 1;
+#if 0
+		/*
+		 * The Linux USB API allows non back-to-back
+		 * isochronous frames which we do not support. If the
+		 * isochronous frames are not back-to-back we need to
+		 * do a copy, and then we need a buffer for
+		 * that. Enable this at your own risk.
+		 */
+		cfg[0].mh.flags.ext_buffer = 1;
+#endif
+		cfg[0].mh.flags.short_xfer_ok = 1;
+
+		bcopy(cfg, cfg + 1, sizeof(*cfg));
+
+		/* Allocate and setup two generic FreeBSD USB transfers */
+
+		if (usb2_transfer_setup(dev->bsd_udev, &uhe->bsd_iface_index,
+		    uhe->bsd_xfer, cfg, 2, uhe, &Giant)) {
+			return (-EINVAL);
+		}
+	} else {
+		if (bufsize > (1 << 22)) {
+			/* limit buffer size */
+			bufsize = (1 << 22);
+		}
+		/* Allocate and setup one generic FreeBSD USB transfer */
+
+		cfg[0].type = type;
+		cfg[0].endpoint = addr & UE_ADDR;
+		cfg[0].direction = addr & (UE_DIR_OUT | UE_DIR_IN);
+		cfg[0].mh.callback = &usb_linux_non_isoc_callback;
+		cfg[0].mh.bufsize = bufsize;
+		cfg[0].mh.flags.ext_buffer = 1;	/* enable zero-copy */
+		cfg[0].mh.flags.proxy_buffer = 1;
+		cfg[0].mh.flags.short_xfer_ok = 1;
+
+		if (usb2_transfer_setup(dev->bsd_udev, &uhe->bsd_iface_index,
+		    uhe->bsd_xfer, cfg, 1, uhe, &Giant)) {
+			return (-EINVAL);
+		}
+	}
+	return (0);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_create_usb_device
+ *
+ * The following function is used to build up a per USB device
+ * structure tree, that mimics the Linux one. The root structure
+ * is returned by this function.
+ *------------------------------------------------------------------------*/
+static struct usb_device *
+usb_linux_create_usb_device(struct usb2_device *udev, device_t dev)
+{
+	struct usb2_config_descriptor *cd = usb2_get_config_descriptor(udev);
+	struct usb2_descriptor *desc;
+	struct usb2_interface_descriptor *id;
+	struct usb2_endpoint_descriptor *ed;
+	struct usb_device *p_ud = NULL;
+	struct usb_interface *p_ui = NULL;
+	struct usb_host_interface *p_uhi = NULL;
+	struct usb_host_endpoint *p_uhe = NULL;
+	uint32_t size;
+	uint16_t niface_total;
+	uint16_t nedesc;
+	uint16_t iface_no_curr;
+	uint16_t iface_index;
+	uint8_t pass;
+	uint8_t iface_no;
+
+	/*
+	 * We do two passes. One pass for computing necessary memory size
+	 * and one pass to initialize all the allocated memory structures.
+	 */
+	for (pass = 0; pass < 2; pass++) {
+
+		iface_no_curr = 0 - 1;
+		niface_total = 0;
+		iface_index = 0;
+		nedesc = 0;
+		desc = NULL;
+
+		/*
+		 * Iterate over all the USB descriptors. Use the USB config
+		 * descriptor pointer provided by the FreeBSD USB stack.
+		 */
+		while ((desc = usb2_desc_foreach(cd, desc))) {
+
+			/*
+			 * Build up a tree according to the descriptors we
+			 * find:
+			 */
+			switch (desc->bDescriptorType) {
+			case UDESC_DEVICE:
+				break;
+
+			case UDESC_ENDPOINT:
+				ed = (void *)desc;
+				if ((ed->bLength < sizeof(*ed)) ||
+				    (iface_index == 0))
+					break;
+				if (p_uhe) {
+					bcopy(ed, &p_uhe->desc, sizeof(p_uhe->desc));
+					p_uhe->bsd_iface_index = iface_index - 1;
+					p_uhe++;
+				}
+				if (p_uhi) {
+					(p_uhi - 1)->desc.bNumEndpoints++;
+				}
+				nedesc++;
+				break;
+
+			case UDESC_INTERFACE:
+				id = (void *)desc;
+				if (id->bLength < sizeof(*id))
+					break;
+				if (p_uhi) {
+					bcopy(id, &p_uhi->desc, sizeof(p_uhi->desc));
+					p_uhi->desc.bNumEndpoints = 0;
+					p_uhi->endpoint = p_uhe;
+					p_uhi->string = "";
+					p_uhi->bsd_iface_index = iface_index;
+					p_uhi++;
+				}
+				iface_no = id->bInterfaceNumber;
+				niface_total++;
+				if (iface_no_curr != iface_no) {
+					if (p_ui) {
+						p_ui->altsetting = p_uhi - 1;
+						p_ui->cur_altsetting = p_uhi - 1;
+						p_ui->num_altsetting = 1;
+						p_ui->bsd_iface_index = iface_index;
+						p_ui->linux_udev = p_ud;
+						p_ui++;
+					}
+					iface_no_curr = iface_no;
+					iface_index++;
+				} else {
+					if (p_ui) {
+						(p_ui - 1)->num_altsetting++;
+					}
+				}
+				break;
+
+			default:
+				break;
+			}
+		}
+
+		if (pass == 0) {
+
+			size = ((sizeof(*p_ud) * 1) +
+			    (sizeof(*p_uhe) * nedesc) +
+			    (sizeof(*p_ui) * iface_index) +
+			    (sizeof(*p_uhi) * niface_total));
+
+			p_ud = malloc(size, M_USBDEV, M_WAITOK | M_ZERO);
+			if (p_ud == NULL) {
+				goto done;
+			}
+			p_uhe = (void *)(p_ud + 1);
+			p_ui = (void *)(p_uhe + nedesc);
+			p_uhi = (void *)(p_ui + iface_index);
+
+			p_ud->product = "";
+			p_ud->manufacturer = "";
+			p_ud->serial = "";
+			p_ud->speed = usb2_get_speed(udev);
+			p_ud->bsd_udev = udev;
+			p_ud->bsd_iface_start = p_ui;
+			p_ud->bsd_iface_end = p_ui + iface_index;
+			p_ud->bsd_endpoint_start = p_uhe;
+			p_ud->bsd_endpoint_end = p_uhe + nedesc;
+			p_ud->devnum = device_get_unit(dev);
+			bcopy(&udev->ddesc, &p_ud->descriptor,
+			    sizeof(p_ud->descriptor));
+			bcopy(udev->default_pipe.edesc, &p_ud->ep0.desc,
+			    sizeof(p_ud->ep0.desc));
+		}
+	}
+done:
+	return (p_ud);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_alloc_urb
+ *
+ * This function should always be used when you allocate an URB for
+ * use with the USB Linux stack. In case of an isochronous transfer
+ * you must specifiy the maximum number of "iso_packets" which you
+ * plan to transfer per URB. This function is always blocking, and
+ * "mem_flags" are not regarded like on Linux.
+ *------------------------------------------------------------------------*/
+struct urb *
+usb_alloc_urb(uint16_t iso_packets, uint16_t mem_flags)
+{
+	struct urb *urb;
+	uint32_t size;
+
+	if (iso_packets == 0xFFFF) {
+		/*
+		 * FreeBSD specific magic value to ask for control transfer
+		 * memory allocation:
+		 */
+		size = sizeof(*urb) + sizeof(struct usb2_device_request) + mem_flags;
+	} else {
+		size = sizeof(*urb) + (iso_packets * sizeof(urb->iso_frame_desc[0]));
+	}
+
+	urb = malloc(size, M_USBDEV, M_WAITOK | M_ZERO);
+	if (urb) {
+
+		usb2_cv_init(&urb->cv_wait, "URBWAIT");
+		if (iso_packets == 0xFFFF) {
+			urb->setup_packet = (void *)(urb + 1);
+			urb->transfer_buffer = (void *)(urb->setup_packet +
+			    sizeof(struct usb2_device_request));
+		} else {
+			urb->number_of_packets = iso_packets;
+		}
+	}
+	return (urb);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_find_host_endpoint
+ *
+ * The following function will return the Linux USB host endpoint
+ * structure that matches the given endpoint type and endpoint
+ * value. If no match is found, NULL is returned. This function is not
+ * part of the Linux USB API and is only used internally.
+ *------------------------------------------------------------------------*/
+struct usb_host_endpoint *
+usb_find_host_endpoint(struct usb_device *dev, uint8_t type, uint8_t ep)
+{
+	struct usb_host_endpoint *uhe;
+	struct usb_host_endpoint *uhe_end;
+	struct usb_host_interface *uhi;
+	struct usb_interface *ui;
+	uint8_t ea;
+	uint8_t at;
+	uint8_t mask;
+
+	if (dev == NULL) {
+		return (NULL);
+	}
+	if (type == UE_CONTROL) {
+		mask = UE_ADDR;
+	} else {
+		mask = (UE_DIR_IN | UE_DIR_OUT | UE_ADDR);
+	}
+
+	ep &= mask;
+
+	/*
+	 * Iterate over all the interfaces searching the selected alternate
+	 * setting only, and all belonging endpoints.
+	 */
+	for (ui = dev->bsd_iface_start;
+	    ui != dev->bsd_iface_end;
+	    ui++) {
+		uhi = ui->cur_altsetting;
+		if (uhi) {
+			uhe_end = uhi->endpoint + uhi->desc.bNumEndpoints;
+			for (uhe = uhi->endpoint;
+			    uhe != uhe_end;
+			    uhe++) {
+				ea = uhe->desc.bEndpointAddress;
+				at = uhe->desc.bmAttributes;
+
+				if (((ea & mask) == ep) &&
+				    ((at & UE_XFERTYPE) == type)) {
+					return (uhe);
+				}
+			}
+		}
+	}
+
+	if ((type == UE_CONTROL) && ((ep & UE_ADDR) == 0)) {
+		return (&dev->ep0);
+	}
+	return (NULL);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_altnum_to_altsetting
+ *
+ * The following function returns a pointer to an alternate setting by
+ * index given a "usb_interface" pointer. If the alternate setting by
+ * index does not exist, NULL is returned. And alternate setting is a
+ * variant of an interface, but usually with slightly different
+ * characteristics.
+ *------------------------------------------------------------------------*/
+struct usb_host_interface *
+usb_altnum_to_altsetting(const struct usb_interface *intf, uint8_t alt_index)
+{
+	if (alt_index >= intf->num_altsetting) {
+		return (NULL);
+	}
+	return (intf->altsetting + alt_index);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_ifnum_to_if
+ *
+ * The following function searches up an USB interface by
+ * "bInterfaceNumber". If no match is found, NULL is returned.
+ *------------------------------------------------------------------------*/
+struct usb_interface *
+usb_ifnum_to_if(struct usb_device *dev, uint8_t iface_no)
+{
+	struct usb_interface *p_ui;
+
+	for (p_ui = dev->bsd_iface_start;
+	    p_ui != dev->bsd_iface_end;
+	    p_ui++) {
+		if ((p_ui->num_altsetting > 0) &&
+		    (p_ui->altsetting->desc.bInterfaceNumber == iface_no)) {
+			return (p_ui);
+		}
+	}
+	return (NULL);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_buffer_alloc
+ *------------------------------------------------------------------------*/
+void   *
+usb_buffer_alloc(struct usb_device *dev, uint32_t size, uint16_t mem_flags, uint8_t *dma_addr)
+{
+	return (malloc(size, M_USBDEV, M_WAITOK | M_ZERO));
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_get_intfdata
+ *------------------------------------------------------------------------*/
+void   *
+usb_get_intfdata(struct usb_interface *intf)
+{
+	return (intf->bsd_priv_sc);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_register
+ *
+ * The following function is used by the "USB_DRIVER_EXPORT()" macro,
+ * and is used to register a Linux USB driver, so that its
+ * "usb_device_id" structures gets searched a probe time. This
+ * function is not part of the Linux USB API, and is for internal use
+ * only.
+ *------------------------------------------------------------------------*/
+void
+usb_linux_register(void *arg)
+{
+	struct usb_driver *drv = arg;
+
+	mtx_lock(&Giant);
+	LIST_INSERT_HEAD(&usb_linux_driver_list, drv, linux_driver_list);
+	mtx_unlock(&Giant);
+
+	usb2_needs_explore_all();
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_deregister
+ *
+ * The following function is used by the "USB_DRIVER_EXPORT()" macro,
+ * and is used to deregister a Linux USB driver. This function will
+ * ensure that all driver instances belonging to the Linux USB device
+ * driver in question, gets detached before the driver is
+ * unloaded. This function is not part of the Linux USB API, and is
+ * for internal use only.
+ *------------------------------------------------------------------------*/
+void
+usb_linux_deregister(void *arg)
+{
+	struct usb_driver *drv = arg;
+	struct usb_linux_softc *sc;
+
+repeat:
+	mtx_lock(&Giant);
+	LIST_FOREACH(sc, &usb_linux_attached_list, sc_attached_list) {
+		if (sc->sc_udrv == drv) {
+			mtx_unlock(&Giant);
+			device_detach(sc->sc_fbsd_dev);
+			goto repeat;
+		}
+	}
+	LIST_REMOVE(drv, linux_driver_list);
+	mtx_unlock(&Giant);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_free_device
+ *
+ * The following function is only used by the FreeBSD USB stack, to
+ * cleanup and free memory after that a Linux USB device was attached.
+ *------------------------------------------------------------------------*/
+void
+usb_linux_free_device(struct usb_device *dev)
+{
+	struct usb_host_endpoint *uhe;
+	struct usb_host_endpoint *uhe_end;
+	int err;
+
+	uhe = dev->bsd_endpoint_start;
+	uhe_end = dev->bsd_endpoint_end;
+	while (uhe != uhe_end) {
+		err = usb_setup_endpoint(dev, uhe, 0);
+		uhe++;
+	}
+	err = usb_setup_endpoint(dev, &dev->ep0, 0);
+	free(dev, M_USBDEV);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_buffer_free
+ *------------------------------------------------------------------------*/
+void
+usb_buffer_free(struct usb_device *dev, uint32_t size,
+    void *addr, uint8_t dma_addr)
+{
+	free(addr, M_USBDEV);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_free_urb
+ *------------------------------------------------------------------------*/
+void
+usb_free_urb(struct urb *urb)
+{
+	if (urb == NULL) {
+		return;
+	}
+	/* make sure that the current URB is not active */
+	usb_kill_urb(urb);
+
+	/* destroy condition variable */
+	usb2_cv_destroy(&urb->cv_wait);
+
+	/* just free it */
+	free(urb, M_USBDEV);
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_init_urb
+ *
+ * The following function can be used to initialize a custom URB. It
+ * is not recommended to use this function. Use "usb_alloc_urb()"
+ * instead.
+ *------------------------------------------------------------------------*/
+void
+usb_init_urb(struct urb *urb)
+{
+	if (urb == NULL) {
+		return;
+	}
+	bzero(urb, sizeof(*urb));
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_kill_urb
+ *------------------------------------------------------------------------*/
+void
+usb_kill_urb(struct urb *urb)
+{
+	if (usb_unlink_urb_sub(urb, 1)) {
+		/* ignore */
+	}
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_set_intfdata
+ *
+ * The following function sets the per Linux USB interface private
+ * data pointer. It is used by most Linux USB device drivers.
+ *------------------------------------------------------------------------*/
+void
+usb_set_intfdata(struct usb_interface *intf, void *data)
+{
+	intf->bsd_priv_sc = data;
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_cleanup_interface
+ *
+ * The following function will release all FreeBSD USB transfers
+ * associated with a Linux USB interface. It is for internal use only.
+ *------------------------------------------------------------------------*/
+static void
+usb_linux_cleanup_interface(struct usb_device *dev, struct usb_interface *iface)
+{
+	struct usb_host_interface *uhi;
+	struct usb_host_interface *uhi_end;
+	struct usb_host_endpoint *uhe;
+	struct usb_host_endpoint *uhe_end;
+	int err;
+
+	uhi = iface->altsetting;
+	uhi_end = iface->altsetting + iface->num_altsetting;
+	while (uhi != uhi_end) {
+		uhe = uhi->endpoint;
+		uhe_end = uhi->endpoint + uhi->desc.bNumEndpoints;
+		while (uhe != uhe_end) {
+			err = usb_setup_endpoint(dev, uhe, 0);
+			uhe++;
+		}
+		uhi++;
+	}
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_wait_complete
+ *
+ * The following function is used by "usb_start_wait_urb()" to wake it
+ * up, when an USB transfer has finished.
+ *------------------------------------------------------------------------*/
+static void
+usb_linux_wait_complete(struct urb *urb)
+{
+	if (urb->transfer_flags & URB_IS_SLEEPING) {
+		usb2_cv_signal(&urb->cv_wait);
+	}
+	urb->transfer_flags &= ~URB_WAIT_WAKEUP;
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_complete
+ *------------------------------------------------------------------------*/
+static void
+usb_linux_complete(struct usb2_xfer *xfer)
+{
+	struct urb *urb;
+
+	urb = xfer->priv_fifo;
+	xfer->priv_fifo = NULL;
+	if (urb->complete) {
+		(urb->complete) (urb);
+	}
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_isoc_callback
+ *
+ * The following is the FreeBSD isochronous USB callback. Isochronous
+ * frames are USB packets transferred 1000 or 8000 times per second,
+ * depending on whether a full- or high- speed USB transfer is
+ * used.
+ *------------------------------------------------------------------------*/
+static void
+usb_linux_isoc_callback(struct usb2_xfer *xfer)
+{
+	uint32_t max_frame = xfer->max_frame_size;
+	uint32_t offset;
+	uint16_t x;
+	struct urb *urb = xfer->priv_fifo;
+	struct usb_host_endpoint *uhe = xfer->priv_sc;
+	struct usb_iso_packet_descriptor *uipd;
+
+	DPRINTF("\n");
+
+	switch (USB_GET_STATE(xfer)) {
+	case USB_ST_TRANSFERRED:
+
+		if (urb->bsd_isread) {
+
+			/* copy in data with regard to the URB */
+
+			offset = 0;
+
+			for (x = 0; x < urb->number_of_packets; x++) {
+				uipd = urb->iso_frame_desc + x;
+				uipd->actual_length = xfer->frlengths[x];
+				uipd->status = 0;
+				if (!xfer->flags.ext_buffer) {
+					usb2_copy_out(xfer->frbuffers, offset,
+					    USB_ADD_BYTES(urb->transfer_buffer,
+					    uipd->offset), uipd->actual_length);
+				}
+				offset += max_frame;
+			}
+		} else {
+			for (x = 0; x < urb->number_of_packets; x++) {
+				uipd = urb->iso_frame_desc + x;
+				uipd->actual_length = xfer->frlengths[x];
+				uipd->status = 0;
+			}
+		}
+
+		urb->actual_length = xfer->actlen;
+
+		/* check for short transfer */
+		if (xfer->actlen < xfer->sumlen) {
+			/* short transfer */
+			if (urb->transfer_flags & URB_SHORT_NOT_OK) {
+				urb->status = -EPIPE;	/* XXX should be
+							 * EREMOTEIO */
+			} else {
+				urb->status = 0;
+			}
+		} else {
+			/* success */
+			urb->status = 0;
+		}
+
+		/* call callback */
+		usb_linux_complete(xfer);
+
+	case USB_ST_SETUP:
+tr_setup:
+
+		if (xfer->priv_fifo == NULL) {
+
+			/* get next transfer */
+			urb = TAILQ_FIRST(&uhe->bsd_urb_list);
+			if (urb == NULL) {
+				/* nothing to do */
+				return;
+			}
+			TAILQ_REMOVE(&uhe->bsd_urb_list, urb, bsd_urb_list);
+			urb->bsd_urb_list.tqe_prev = NULL;
+
+			x = xfer->max_frame_count;
+			if (urb->number_of_packets > x) {
+				/* XXX simply truncate the transfer */
+				urb->number_of_packets = x;
+			}
+		} else {
+			DPRINTF("Already got a transfer\n");
+
+			/* already got a transfer (should not happen) */
+			urb = xfer->priv_fifo;
+		}
+
+		urb->bsd_isread = (uhe->desc.bEndpointAddress & UE_DIR_IN) ? 1 : 0;
+
+		if (!(urb->bsd_isread)) {
+
+			/* copy out data with regard to the URB */
+
+			offset = 0;
+
+			for (x = 0; x < urb->number_of_packets; x++) {
+				uipd = urb->iso_frame_desc + x;
+				xfer->frlengths[x] = uipd->length;
+				if (!xfer->flags.ext_buffer) {
+					usb2_copy_in(xfer->frbuffers, offset,
+					    USB_ADD_BYTES(urb->transfer_buffer,
+					    uipd->offset), uipd->length);
+				}
+				offset += uipd->length;
+			}
+		} else {
+
+			/*
+			 * compute the transfer length into the "offset"
+			 * variable
+			 */
+
+			offset = urb->number_of_packets * max_frame;
+
+			/* setup "frlengths" array */
+
+			for (x = 0; x < urb->number_of_packets; x++) {
+				uipd = urb->iso_frame_desc + x;
+				xfer->frlengths[x] = max_frame;
+			}
+		}
+
+		if (xfer->flags.ext_buffer) {
+			/* set virtual address to load */
+			usb2_set_frame_data(xfer,
+			    urb->transfer_buffer, 0);
+		}
+		xfer->priv_fifo = urb;
+		xfer->flags.force_short_xfer = 0;
+		xfer->timeout = urb->timeout;
+		xfer->nframes = urb->number_of_packets;
+		usb2_start_hardware(xfer);
+		return;
+
+	default:			/* Error */
+		if (xfer->error == USB_ERR_CANCELLED) {
+			urb->status = -ECONNRESET;
+		} else {
+			urb->status = -EPIPE;	/* stalled */
+		}
+
+		/* Set zero for "actual_length" */
+		urb->actual_length = 0;
+
+		/* Set zero for "actual_length" */
+		for (x = 0; x < urb->number_of_packets; x++) {
+			urb->iso_frame_desc[x].actual_length = 0;
+		}
+
+		/* call callback */
+		usb_linux_complete(xfer);
+
+		if (xfer->error == USB_ERR_CANCELLED) {
+			/* we need to return in this case */
+			return;
+		}
+		goto tr_setup;
+
+	}
+}
+
+/*------------------------------------------------------------------------*
+ *	usb_linux_non_isoc_callback
+ *
+ * The following is the FreeBSD BULK/INTERRUPT and CONTROL USB
+ * callback. It dequeues Linux USB stack compatible URB's, transforms
+ * the URB fields into a FreeBSD USB transfer, and defragments the USB
+ * transfer as required. When the transfer is complete the "complete"
+ * callback is called.
+ *------------------------------------------------------------------------*/
+static void
+usb_linux_non_isoc_callback(struct usb2_xfer *xfer)
+{
+	enum {
+		REQ_SIZE = sizeof(struct usb2_device_request)
+	};
+	struct urb *urb = xfer->priv_fifo;
+	struct usb_host_endpoint *uhe = xfer->priv_sc;
+	uint8_t *ptr;
+	uint32_t max_bulk = xfer->max_data_length;
+	uint8_t data_frame = xfer->flags_int.control_xfr ? 1 : 0;
+
+	DPRINTF("\n");
+
+	switch (USB_GET_STATE(xfer)) {
+	case USB_ST_TRANSFERRED:
+
+		if (xfer->flags_int.control_xfr) {
+
+			/* don't transfer the setup packet again: */
+
+			xfer->frlengths[0] = 0;
+		}
+		if (urb->bsd_isread && (!xfer->flags.ext_buffer)) {
+			/* copy in data with regard to the URB */
+			usb2_copy_out(xfer->frbuffers + data_frame, 0,
+			    urb->bsd_data_ptr, xfer->frlengths[data_frame]);
+		}
+		urb->bsd_length_rem -= xfer->frlengths[data_frame];
+		urb->bsd_data_ptr += xfer->frlengths[data_frame];
+		urb->actual_length += xfer->frlengths[data_frame];
+
+		/* check for short transfer */
+		if (xfer->actlen < xfer->sumlen) {
+			urb->bsd_length_rem = 0;
+
+			/* short transfer */
+			if (urb->transfer_flags & URB_SHORT_NOT_OK) {
+				urb->status = -EPIPE;
+			} else {
+				urb->status = 0;
+			}
+		} else {
+			/* check remainder */
+			if (urb->bsd_length_rem > 0) {
+				goto setup_bulk;
+			}
+			/* success */
+			urb->status = 0;
+		}
+
+		/* call callback */
+		usb_linux_complete(xfer);
+
+	case USB_ST_SETUP:
+tr_setup:
+		/* get next transfer */
+		urb = TAILQ_FIRST(&uhe->bsd_urb_list);
+		if (urb == NULL) {
+			/* nothing to do */
+			return;
+		}
+		TAILQ_REMOVE(&uhe->bsd_urb_list, urb, bsd_urb_list);
+		urb->bsd_urb_list.tqe_prev = NULL;
+
+		xfer->priv_fifo = urb;
+		xfer->flags.force_short_xfer = 0;
+		xfer->timeout = urb->timeout;
+
+		if (xfer->flags_int.control_xfr) {
+
+			/*
+		         * USB control transfers need special handling.
+		         * First copy in the header, then copy in data!
+		         */
+			if (!xfer->flags.ext_buffer) {
+				usb2_copy_in(xfer->frbuffers, 0,
+				    urb->setup_packet, REQ_SIZE);
+			} else {
+				/* set virtual address to load */
+				usb2_set_frame_data(xfer,
+				    urb->setup_packet, 0);
+			}
+
+			xfer->frlengths[0] = REQ_SIZE;
+
+			ptr = urb->setup_packet;
+
+			/* setup data transfer direction and length */
+			urb->bsd_isread = (ptr[0] & UT_READ) ? 1 : 0;
+			urb->bsd_length_rem = ptr[6] | (ptr[7] << 8);
+
+		} else {
+
+			/* setup data transfer direction */
+
+			urb->bsd_length_rem = urb->transfer_buffer_length;
+			urb->bsd_isread = (uhe->desc.bEndpointAddress &
+			    UE_DIR_IN) ? 1 : 0;
+		}
+
+		urb->bsd_data_ptr = urb->transfer_buffer;
+		urb->actual_length = 0;
+
+setup_bulk:
+		if (max_bulk > urb->bsd_length_rem) {
+			max_bulk = urb->bsd_length_rem;
+		}
+		/* check if we need to force a short transfer */
+
+		if ((max_bulk == urb->bsd_length_rem) &&
+		    (urb->transfer_flags & URB_ZERO_PACKET) &&
+		    (!xfer->flags_int.control_xfr)) {
+			xfer->flags.force_short_xfer = 1;
+		}
+		/* check if we need to copy in data */
+
+		if (xfer->flags.ext_buffer) {
+			/* set virtual address to load */
+			usb2_set_frame_data(xfer, urb->bsd_data_ptr,
+			    data_frame);
+		} else if (!urb->bsd_isread) {
+			/* copy out data with regard to the URB */
+			usb2_copy_in(xfer->frbuffers + data_frame, 0,
+			    urb->bsd_data_ptr, max_bulk);
+		}
+		xfer->frlengths[data_frame] = max_bulk;
+		if (xfer->flags_int.control_xfr) {
+			if (max_bulk > 0) {
+				xfer->nframes = 2;
+			} else {
+				xfer->nframes = 1;
+			}
+		} else {
+			xfer->nframes = 1;
+		}
+		usb2_start_hardware(xfer);
+		return;
+
+	default:
+		if (xfer->error == USB_ERR_CANCELLED) {
+			urb->status = -ECONNRESET;
+		} else {
+			urb->status = -EPIPE;
+		}
+
+		/* Set zero for "actual_length" */
+		urb->actual_length = 0;
+
+		/* call callback */
+		usb_linux_complete(xfer);
+
+		if (xfer->error == USB_ERR_CANCELLED) {
+			/* we need to return in this case */
+			return;
+		}
+		goto tr_setup;
+	}
+}