xref: /src/sys/dev/usb/uhci.c

/*	$NetBSD: uhci.c,v 1.232 2010/02/24 22:38:09 dyoung Exp $	*/
/*	$FreeBSD: src/sys/dev/usb/uhci.c,v 1.33 1999/11/17 22:33:41 n_hibma Exp $	*/

/*
 * Copyright (c) 1998, 2004 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Lennart Augustsson (lennart (at) augustsson.net) at
 * Carlstedt Research & Technology.
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

/*
 * USB Universal Host Controller driver.
 * Handles e.g. PIIX3 and PIIX4.
 *
 * UHCI spec: http://www.intel.com/technology/usb/spec.htm
 * USB spec: http://www.usb.org/developers/docs/
 * PIIXn spec: ftp://download.intel.com/design/intarch/datashts/29055002.pdf
 *             ftp://download.intel.com/design/intarch/datashts/29056201.pdf
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: uhci.c,v 1.232 2010/02/24 22:38:09 dyoung Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/device.h>
#include <sys/select.h>
#include <sys/extent.h>
#include <uvm/uvm_extern.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/bus.h>

#include <machine/endian.h>

#include <dev/usb/usb.h>
#include <dev/usb/usbdi.h>
#include <dev/usb/usbdivar.h>
#include <dev/usb/usb_mem.h>
#include <dev/usb/usb_quirks.h>

#include <dev/usb/uhcireg.h>
#include <dev/usb/uhcivar.h>
#include <dev/usb/usbroothub_subr.h>

/* Use bandwidth reclamation for control transfers. Some devices choke on it. */
/*#define UHCI_CTL_LOOP */



#ifdef UHCI_DEBUG
uhci_softc_t *thesc;
#define DPRINTF(x)	if (uhcidebug) printf x
#define DPRINTFN(n,x)	if (uhcidebug>(n)) printf x
int uhcidebug = 0;
int uhcinoloop = 0;
#else
#define DPRINTF(x)
#define DPRINTFN(n,x)
#endif

/*
 * The UHCI controller is little endian, so on big endian machines
 * the data stored in memory needs to be swapped.
 */

struct uhci_pipe {
	struct usbd_pipe pipe;
	int nexttoggle;

	u_char aborting;
	usbd_xfer_handle abortstart, abortend;

	/* Info needed for different pipe kinds. */
	union {
		/* Control pipe */
		struct {
			uhci_soft_qh_t *sqh;
			usb_dma_t reqdma;
			uhci_soft_td_t *setup, *stat;
			u_int length;
		} ctl;
		/* Interrupt pipe */
		struct {
			int npoll;
			int isread;
			uhci_soft_qh_t **qhs;
		} intr;
		/* Bulk pipe */
		struct {
			uhci_soft_qh_t *sqh;
			u_int length;
			int isread;
		} bulk;
		/* Iso pipe */
		struct iso {
			uhci_soft_td_t **stds;
			int next, inuse;
		} iso;
	} u;
};

Static void		uhci_globalreset(uhci_softc_t *);
Static usbd_status	uhci_portreset(uhci_softc_t*, int);
Static void		uhci_reset(uhci_softc_t *);
Static usbd_status	uhci_run(uhci_softc_t *, int run);
Static uhci_soft_td_t  *uhci_alloc_std(uhci_softc_t *);
Static void		uhci_free_std(uhci_softc_t *, uhci_soft_td_t *);
Static uhci_soft_qh_t  *uhci_alloc_sqh(uhci_softc_t *);
Static void		uhci_free_sqh(uhci_softc_t *, uhci_soft_qh_t *);
#if 0
Static void		uhci_enter_ctl_q(uhci_softc_t *, uhci_soft_qh_t *,
					 uhci_intr_info_t *);
Static void		uhci_exit_ctl_q(uhci_softc_t *, uhci_soft_qh_t *);
#endif

Static void		uhci_free_std_chain(uhci_softc_t *,
					    uhci_soft_td_t *, uhci_soft_td_t *);
Static usbd_status	uhci_alloc_std_chain(struct uhci_pipe *,
			    uhci_softc_t *, int, int, u_int16_t, usb_dma_t *,
			    uhci_soft_td_t **, uhci_soft_td_t **);
Static void		uhci_poll_hub(void *);
Static void		uhci_waitintr(uhci_softc_t *, usbd_xfer_handle);
Static void		uhci_check_intr(uhci_softc_t *, uhci_intr_info_t *);
Static void		uhci_idone(uhci_intr_info_t *);

Static void		uhci_abort_xfer(usbd_xfer_handle, usbd_status status);

Static void		uhci_timeout(void *);
Static void		uhci_timeout_task(void *);
Static void		uhci_add_ls_ctrl(uhci_softc_t *, uhci_soft_qh_t *);
Static void		uhci_add_hs_ctrl(uhci_softc_t *, uhci_soft_qh_t *);
Static void		uhci_add_bulk(uhci_softc_t *, uhci_soft_qh_t *);
Static void		uhci_remove_ls_ctrl(uhci_softc_t *,uhci_soft_qh_t *);
Static void		uhci_remove_hs_ctrl(uhci_softc_t *,uhci_soft_qh_t *);
Static void		uhci_remove_bulk(uhci_softc_t *,uhci_soft_qh_t *);
Static void		uhci_add_loop(uhci_softc_t *sc);
Static void		uhci_rem_loop(uhci_softc_t *sc);

Static usbd_status	uhci_setup_isoc(usbd_pipe_handle pipe);
Static void		uhci_device_isoc_enter(usbd_xfer_handle);

Static usbd_status	uhci_allocm(struct usbd_bus *, usb_dma_t *, u_int32_t);
Static void		uhci_freem(struct usbd_bus *, usb_dma_t *);

Static usbd_xfer_handle	uhci_allocx(struct usbd_bus *);
Static void		uhci_freex(struct usbd_bus *, usbd_xfer_handle);

Static usbd_status	uhci_device_ctrl_transfer(usbd_xfer_handle);
Static usbd_status	uhci_device_ctrl_start(usbd_xfer_handle);
Static void		uhci_device_ctrl_abort(usbd_xfer_handle);
Static void		uhci_device_ctrl_close(usbd_pipe_handle);
Static void		uhci_device_ctrl_done(usbd_xfer_handle);

Static usbd_status	uhci_device_intr_transfer(usbd_xfer_handle);
Static usbd_status	uhci_device_intr_start(usbd_xfer_handle);
Static void		uhci_device_intr_abort(usbd_xfer_handle);
Static void		uhci_device_intr_close(usbd_pipe_handle);
Static void		uhci_device_intr_done(usbd_xfer_handle);

Static usbd_status	uhci_device_bulk_transfer(usbd_xfer_handle);
Static usbd_status	uhci_device_bulk_start(usbd_xfer_handle);
Static void		uhci_device_bulk_abort(usbd_xfer_handle);
Static void		uhci_device_bulk_close(usbd_pipe_handle);
Static void		uhci_device_bulk_done(usbd_xfer_handle);

Static usbd_status	uhci_device_isoc_transfer(usbd_xfer_handle);
Static usbd_status	uhci_device_isoc_start(usbd_xfer_handle);
Static void		uhci_device_isoc_abort(usbd_xfer_handle);
Static void		uhci_device_isoc_close(usbd_pipe_handle);
Static void		uhci_device_isoc_done(usbd_xfer_handle);

Static usbd_status	uhci_root_ctrl_transfer(usbd_xfer_handle);
Static usbd_status	uhci_root_ctrl_start(usbd_xfer_handle);
Static void		uhci_root_ctrl_abort(usbd_xfer_handle);
Static void		uhci_root_ctrl_close(usbd_pipe_handle);
Static void		uhci_root_ctrl_done(usbd_xfer_handle);

Static usbd_status	uhci_root_intr_transfer(usbd_xfer_handle);
Static usbd_status	uhci_root_intr_start(usbd_xfer_handle);
Static void		uhci_root_intr_abort(usbd_xfer_handle);
Static void		uhci_root_intr_close(usbd_pipe_handle);
Static void		uhci_root_intr_done(usbd_xfer_handle);

Static usbd_status	uhci_open(usbd_pipe_handle);
Static void		uhci_poll(struct usbd_bus *);
Static void		uhci_softintr(void *);

Static usbd_status	uhci_device_request(usbd_xfer_handle xfer);

Static void		uhci_add_intr(uhci_softc_t *, uhci_soft_qh_t *);
Static void		uhci_remove_intr(uhci_softc_t *, uhci_soft_qh_t *);
Static usbd_status	uhci_device_setintr(uhci_softc_t *sc,
			    struct uhci_pipe *pipe, int ival);

Static void		uhci_device_clear_toggle(usbd_pipe_handle pipe);
Static void		uhci_noop(usbd_pipe_handle pipe);

Static inline uhci_soft_qh_t *uhci_find_prev_qh(uhci_soft_qh_t *,
						    uhci_soft_qh_t *);

#ifdef UHCI_DEBUG
Static void		uhci_dump_all(uhci_softc_t *);
Static void		uhci_dumpregs(uhci_softc_t *);
Static void		uhci_dump_qhs(uhci_soft_qh_t *);
Static void		uhci_dump_qh(uhci_soft_qh_t *);
Static void		uhci_dump_tds(uhci_soft_td_t *);
Static void		uhci_dump_td(uhci_soft_td_t *);
Static void		uhci_dump_ii(uhci_intr_info_t *ii);
void			uhci_dump(void);
#endif

#define UBARR(sc) bus_space_barrier((sc)->iot, (sc)->ioh, 0, (sc)->sc_size, \
			BUS_SPACE_BARRIER_READ|BUS_SPACE_BARRIER_WRITE)
#define UWRITE1(sc, r, x) \
 do { UBARR(sc); bus_space_write_1((sc)->iot, (sc)->ioh, (r), (x)); \
 } while (/*CONSTCOND*/0)
#define UWRITE2(sc, r, x) \
 do { UBARR(sc); bus_space_write_2((sc)->iot, (sc)->ioh, (r), (x)); \
 } while (/*CONSTCOND*/0)
#define UWRITE4(sc, r, x) \
 do { UBARR(sc); bus_space_write_4((sc)->iot, (sc)->ioh, (r), (x)); \
 } while (/*CONSTCOND*/0)
static __inline uint8_t
UREAD1(uhci_softc_t *sc, bus_size_t r)
{

	UBARR(sc);
	return bus_space_read_1(sc->iot, sc->ioh, r);
}

static __inline uint16_t
UREAD2(uhci_softc_t *sc, bus_size_t r)
{

	UBARR(sc);
	return bus_space_read_2(sc->iot, sc->ioh, r);
}

static __inline uint32_t
UREAD4(uhci_softc_t *sc, bus_size_t r)
{

	UBARR(sc);
	return bus_space_read_4(sc->iot, sc->ioh, r);
}

#define UHCICMD(sc, cmd) UWRITE2(sc, UHCI_CMD, cmd)
#define UHCISTS(sc) UREAD2(sc, UHCI_STS)

#define UHCI_RESET_TIMEOUT 100	/* ms, reset timeout */

#define UHCI_CURFRAME(sc) (UREAD2(sc, UHCI_FRNUM) & UHCI_FRNUM_MASK)

#define UHCI_INTR_ENDPT 1

const struct usbd_bus_methods uhci_bus_methods = {
	uhci_open,
	uhci_softintr,
	uhci_poll,
	uhci_allocm,
	uhci_freem,
	uhci_allocx,
	uhci_freex,
};

const struct usbd_pipe_methods uhci_root_ctrl_methods = {
	uhci_root_ctrl_transfer,
	uhci_root_ctrl_start,
	uhci_root_ctrl_abort,
	uhci_root_ctrl_close,
	uhci_noop,
	uhci_root_ctrl_done,
};

const struct usbd_pipe_methods uhci_root_intr_methods = {
	uhci_root_intr_transfer,
	uhci_root_intr_start,
	uhci_root_intr_abort,
	uhci_root_intr_close,
	uhci_noop,
	uhci_root_intr_done,
};

const struct usbd_pipe_methods uhci_device_ctrl_methods = {
	uhci_device_ctrl_transfer,
	uhci_device_ctrl_start,
	uhci_device_ctrl_abort,
	uhci_device_ctrl_close,
	uhci_noop,
	uhci_device_ctrl_done,
};

const struct usbd_pipe_methods uhci_device_intr_methods = {
	uhci_device_intr_transfer,
	uhci_device_intr_start,
	uhci_device_intr_abort,
	uhci_device_intr_close,
	uhci_device_clear_toggle,
	uhci_device_intr_done,
};

const struct usbd_pipe_methods uhci_device_bulk_methods = {
	uhci_device_bulk_transfer,
	uhci_device_bulk_start,
	uhci_device_bulk_abort,
	uhci_device_bulk_close,
	uhci_device_clear_toggle,
	uhci_device_bulk_done,
};

const struct usbd_pipe_methods uhci_device_isoc_methods = {
	uhci_device_isoc_transfer,
	uhci_device_isoc_start,
	uhci_device_isoc_abort,
	uhci_device_isoc_close,
	uhci_noop,
	uhci_device_isoc_done,
};

#define uhci_add_intr_info(sc, ii) \
	LIST_INSERT_HEAD(&(sc)->sc_intrhead, (ii), list)
#define uhci_del_intr_info(ii) \
	do { \
		LIST_REMOVE((ii), list); \
		(ii)->list.le_prev = NULL; \
	} while (0)
#define uhci_active_intr_info(ii) ((ii)->list.le_prev != NULL)

Static inline uhci_soft_qh_t *
uhci_find_prev_qh(uhci_soft_qh_t *pqh, uhci_soft_qh_t *sqh)
{
	DPRINTFN(15,("uhci_find_prev_qh: pqh=%p sqh=%p\n", pqh, sqh));

	for (; pqh->hlink != sqh; pqh = pqh->hlink) {
#if defined(DIAGNOSTIC) || defined(UHCI_DEBUG)
		usb_syncmem(&pqh->dma,
		    pqh->offs + offsetof(uhci_qh_t, qh_hlink),
		    sizeof(pqh->qh.qh_hlink),
		    BUS_DMASYNC_POSTWRITE);
		if (le32toh(pqh->qh.qh_hlink) & UHCI_PTR_T) {
			printf("uhci_find_prev_qh: QH not found\n");
			return (NULL);
		}
#endif
	}
	return (pqh);
}

void
uhci_globalreset(uhci_softc_t *sc)
{
	UHCICMD(sc, UHCI_CMD_GRESET);	/* global reset */
	usb_delay_ms(&sc->sc_bus, USB_BUS_RESET_DELAY); /* wait a little */
	UHCICMD(sc, 0);			/* do nothing */
}

usbd_status
uhci_init(uhci_softc_t *sc)
{
	usbd_status err;
	int i, j;
	uhci_soft_qh_t *clsqh, *chsqh, *bsqh, *sqh, *lsqh;
	uhci_soft_td_t *std;

	DPRINTFN(1,("uhci_init: start\n"));

#ifdef UHCI_DEBUG
	thesc = sc;

	if (uhcidebug > 2)
		uhci_dumpregs(sc);
#endif

	sc->sc_suspend = PWR_RESUME;

	UWRITE2(sc, UHCI_INTR, 0);		/* disable interrupts */
	uhci_globalreset(sc);			/* reset the controller */
	uhci_reset(sc);

	usb_setup_reserve(sc->sc_dev, &sc->sc_dma_reserve, sc->sc_bus.dmatag,
	    USB_MEM_RESERVE);

	/* Allocate and initialize real frame array. */
	err = usb_allocmem(&sc->sc_bus,
		  UHCI_FRAMELIST_COUNT * sizeof(uhci_physaddr_t),
		  UHCI_FRAMELIST_ALIGN, &sc->sc_dma);
	if (err)
		return (err);
	sc->sc_pframes = KERNADDR(&sc->sc_dma, 0);
	UWRITE2(sc, UHCI_FRNUM, 0);		/* set frame number to 0 */
	UWRITE4(sc, UHCI_FLBASEADDR, DMAADDR(&sc->sc_dma, 0)); /* set frame list*/

	/*
	 * Allocate a TD, inactive, that hangs from the last QH.
	 * This is to avoid a bug in the PIIX that makes it run berserk
	 * otherwise.
	 */
	std = uhci_alloc_std(sc);
	if (std == NULL)
		return (USBD_NOMEM);
	std->link.std = NULL;
	std->td.td_link = htole32(UHCI_PTR_T);
	std->td.td_status = htole32(0); /* inactive */
	std->td.td_token = htole32(0);
	std->td.td_buffer = htole32(0);
	usb_syncmem(&std->dma, std->offs, sizeof(std->td),
	    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);

	/* Allocate the dummy QH marking the end and used for looping the QHs.*/
	lsqh = uhci_alloc_sqh(sc);
	if (lsqh == NULL)
		return (USBD_NOMEM);
	lsqh->hlink = NULL;
	lsqh->qh.qh_hlink = htole32(UHCI_PTR_T);	/* end of QH chain */
	lsqh->elink = std;
	lsqh->qh.qh_elink = htole32(std->physaddr | UHCI_PTR_TD);
	sc->sc_last_qh = lsqh;
	usb_syncmem(&lsqh->dma, lsqh->offs, sizeof(lsqh->qh),
	    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);

	/* Allocate the dummy QH where bulk traffic will be queued. */
	bsqh = uhci_alloc_sqh(sc);
	if (bsqh == NULL)
		return (USBD_NOMEM);
	bsqh->hlink = lsqh;
	bsqh->qh.qh_hlink = htole32(lsqh->physaddr | UHCI_PTR_QH);
	bsqh->elink = NULL;
	bsqh->qh.qh_elink = htole32(UHCI_PTR_T);
	sc->sc_bulk_start = sc->sc_bulk_end = bsqh;
	usb_syncmem(&bsqh->dma, bsqh->offs, sizeof(bsqh->qh),
	    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);

	/* Allocate dummy QH where high speed control traffic will be queued. */
	chsqh = uhci_alloc_sqh(sc);
	if (chsqh == NULL)
		return (USBD_NOMEM);
	chsqh->hlink = bsqh;
	chsqh->qh.qh_hlink = htole32(bsqh->physaddr | UHCI_PTR_QH);
	chsqh->elink = NULL;
	chsqh->qh.qh_elink = htole32(UHCI_PTR_T);
	sc->sc_hctl_start = sc->sc_hctl_end = chsqh;
	usb_syncmem(&chsqh->dma, chsqh->offs, sizeof(chsqh->qh),
	    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);

	/* Allocate dummy QH where control traffic will be queued. */
	clsqh = uhci_alloc_sqh(sc);
	if (clsqh == NULL)
		return (USBD_NOMEM);
	clsqh->hlink = chsqh;
	clsqh->qh.qh_hlink = htole32(chsqh->physaddr | UHCI_PTR_QH);
	clsqh->elink = NULL;
	clsqh->qh.qh_elink = htole32(UHCI_PTR_T);
	sc->sc_lctl_start = sc->sc_lctl_end = clsqh;
	usb_syncmem(&clsqh->dma, clsqh->offs, sizeof(clsqh->qh),
	    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);

	/*
	 * Make all (virtual) frame list pointers point to the interrupt
	 * queue heads and the interrupt queue heads at the control
	 * queue head and point the physical frame list to the virtual.
	 */
	for(i = 0; i < UHCI_VFRAMELIST_COUNT; i++) {
		std = uhci_alloc_std(sc);
		sqh = uhci_alloc_sqh(sc);
		if (std == NULL || sqh == NULL)
			return (USBD_NOMEM);
		std->link.sqh = sqh;
		std->td.td_link = htole32(sqh->physaddr | UHCI_PTR_QH);
		std->td.td_status = htole32(UHCI_TD_IOS); /* iso, inactive */
		std->td.td_token = htole32(0);
		std->td.td_buffer = htole32(0);
		usb_syncmem(&std->dma, std->offs, sizeof(std->td),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
		sqh->hlink = clsqh;
		sqh->qh.qh_hlink = htole32(clsqh->physaddr | UHCI_PTR_QH);
		sqh->elink = NULL;
		sqh->qh.qh_elink = htole32(UHCI_PTR_T);
		usb_syncmem(&sqh->dma, sqh->offs, sizeof(sqh->qh),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
		sc->sc_vframes[i].htd = std;
		sc->sc_vframes[i].etd = std;
		sc->sc_vframes[i].hqh = sqh;
		sc->sc_vframes[i].eqh = sqh;
		for (j = i;
		     j < UHCI_FRAMELIST_COUNT;
		     j += UHCI_VFRAMELIST_COUNT)
			sc->sc_pframes[j] = htole32(std->physaddr);
	}
	usb_syncmem(&sc->sc_dma, 0,
	    UHCI_FRAMELIST_COUNT * sizeof(uhci_physaddr_t),
	    BUS_DMASYNC_PREWRITE);


	LIST_INIT(&sc->sc_intrhead);

	SIMPLEQ_INIT(&sc->sc_free_xfers);

	usb_callout_init(sc->sc_poll_handle);

	/* Set up the bus struct. */
	sc->sc_bus.methods = &uhci_bus_methods;
	sc->sc_bus.pipe_size = sizeof(struct uhci_pipe);

	UHCICMD(sc, UHCI_CMD_MAXP); /* Assume 64 byte packets at frame end */

	DPRINTFN(1,("uhci_init: enabling\n"));

	err =  uhci_run(sc, 1);		/* and here we go... */
	UWRITE2(sc, UHCI_INTR, UHCI_INTR_TOCRCIE | UHCI_INTR_RIE |
		UHCI_INTR_IOCE | UHCI_INTR_SPIE);	/* enable interrupts */
	return err;
}

int
uhci_activate(device_t self, enum devact act)
{
	struct uhci_softc *sc = device_private(self);

	switch (act) {
	case DVACT_DEACTIVATE:
		sc->sc_dying = 1;
		return 0;
	default:
		return EOPNOTSUPP;
	}
}

void
uhci_childdet(device_t self, device_t child)
{
	struct uhci_softc *sc = device_private(self);

	KASSERT(sc->sc_child == child);
	sc->sc_child = NULL;
}

int
uhci_detach(struct uhci_softc *sc, int flags)
{
	usbd_xfer_handle xfer;
	int rv = 0;

	if (sc->sc_child != NULL)
		rv = config_detach(sc->sc_child, flags);

	if (rv != 0)
		return (rv);

	/* Free all xfers associated with this HC. */
	for (;;) {
		xfer = SIMPLEQ_FIRST(&sc->sc_free_xfers);
		if (xfer == NULL)
			break;
		SIMPLEQ_REMOVE_HEAD(&sc->sc_free_xfers, next);
		free(xfer, M_USB);
	}

	callout_halt(&sc->sc_poll_handle, NULL);
	callout_destroy(&sc->sc_poll_handle);

	/* XXX free other data structures XXX */

	return (rv);
}

usbd_status
uhci_allocm(struct usbd_bus *bus, usb_dma_t *dma, u_int32_t size)
{
	struct uhci_softc *sc = bus->hci_private;
	usbd_status status;
	u_int32_t n;

	/*
	 * XXX
	 * Since we are allocating a buffer we can assume that we will
	 * need TDs for it.  Since we don't want to allocate those from
	 * an interrupt context, we allocate them here and free them again.
	 * This is no guarantee that we'll get the TDs next time...
	 */
	n = size / 8;
	if (n > 16) {
		u_int32_t i;
		uhci_soft_td_t **stds;
		DPRINTF(("uhci_allocm: get %d TDs\n", n));
		stds = malloc(sizeof(uhci_soft_td_t *) * n, M_TEMP,
		    M_WAITOK|M_ZERO);
		for(i=0; i < n; i++)
			stds[i] = uhci_alloc_std(sc);
		for(i=0; i < n; i++)
			if (stds[i] != NULL)
				uhci_free_std(sc, stds[i]);
		free(stds, M_TEMP);
	}


	status = usb_allocmem(&sc->sc_bus, size, 0, dma);
	if (status == USBD_NOMEM)
		status = usb_reserve_allocm(&sc->sc_dma_reserve, dma, size);
	return status;
}

void
uhci_freem(struct usbd_bus *bus, usb_dma_t *dma)
{
	if (dma->block->flags & USB_DMA_RESERVE) {
		usb_reserve_freem(&((struct uhci_softc *)bus)->sc_dma_reserve,
		    dma);
		return;
	}
	usb_freemem(&((struct uhci_softc *)bus)->sc_bus, dma);
}

usbd_xfer_handle
uhci_allocx(struct usbd_bus *bus)
{
	struct uhci_softc *sc = bus->hci_private;
	usbd_xfer_handle xfer;

	xfer = SIMPLEQ_FIRST(&sc->sc_free_xfers);
	if (xfer != NULL) {
		SIMPLEQ_REMOVE_HEAD(&sc->sc_free_xfers, next);
#ifdef DIAGNOSTIC
		if (xfer->busy_free != XFER_FREE) {
			printf("uhci_allocx: xfer=%p not free, 0x%08x\n", xfer,
			       xfer->busy_free);
		}
#endif
	} else {
		xfer = malloc(sizeof(struct uhci_xfer), M_USB, M_NOWAIT);
	}
	if (xfer != NULL) {
		memset(xfer, 0, sizeof (struct uhci_xfer));
		UXFER(xfer)->iinfo.sc = sc;
#ifdef DIAGNOSTIC
		UXFER(xfer)->iinfo.isdone = 1;
		xfer->busy_free = XFER_BUSY;
#endif
	}
	return (xfer);
}

void
uhci_freex(struct usbd_bus *bus, usbd_xfer_handle xfer)
{
	struct uhci_softc *sc = bus->hci_private;

#ifdef DIAGNOSTIC
	if (xfer->busy_free != XFER_BUSY) {
		printf("uhci_freex: xfer=%p not busy, 0x%08x\n", xfer,
		       xfer->busy_free);
	}
	xfer->busy_free = XFER_FREE;
	if (!UXFER(xfer)->iinfo.isdone) {
		printf("uhci_freex: !isdone\n");
	}
#endif
	SIMPLEQ_INSERT_HEAD(&sc->sc_free_xfers, xfer, next);
}

/*
 * Handle suspend/resume.
 *
 * We need to switch to polling mode here, because this routine is
 * called from an interrupt context.  This is all right since we
 * are almost suspended anyway.
 */
bool
uhci_resume(device_t dv, const pmf_qual_t *qual)
{
	uhci_softc_t *sc = device_private(dv);
	int cmd;
	int s;

	s = splhardusb();

	cmd = UREAD2(sc, UHCI_CMD);
	sc->sc_bus.use_polling++;
	UWRITE2(sc, UHCI_INTR, 0);
	uhci_globalreset(sc);
	uhci_reset(sc);
	if (cmd & UHCI_CMD_RS)
		uhci_run(sc, 0);

	/* restore saved state */
	UWRITE4(sc, UHCI_FLBASEADDR, DMAADDR(&sc->sc_dma, 0));
	UWRITE2(sc, UHCI_FRNUM, sc->sc_saved_frnum);
	UWRITE1(sc, UHCI_SOF, sc->sc_saved_sof);

	UHCICMD(sc, cmd | UHCI_CMD_FGR); /* force resume */
	usb_delay_ms(&sc->sc_bus, USB_RESUME_DELAY);
	UHCICMD(sc, cmd & ~UHCI_CMD_EGSM); /* back to normal */
	UWRITE2(sc, UHCI_INTR, UHCI_INTR_TOCRCIE |
	    UHCI_INTR_RIE | UHCI_INTR_IOCE | UHCI_INTR_SPIE);
	UHCICMD(sc, UHCI_CMD_MAXP);
	uhci_run(sc, 1); /* and start traffic again */
	usb_delay_ms(&sc->sc_bus, USB_RESUME_RECOVERY);
	sc->sc_bus.use_polling--;
	if (sc->sc_intr_xfer != NULL)
		usb_callout(sc->sc_poll_handle, sc->sc_ival, uhci_poll_hub,
		    sc->sc_intr_xfer);
#ifdef UHCI_DEBUG
	if (uhcidebug > 2)
		uhci_dumpregs(sc);
#endif

	sc->sc_suspend = PWR_RESUME;
	splx(s);

	return true;
}

bool
uhci_suspend(device_t dv, const pmf_qual_t *qual)
{
	uhci_softc_t *sc = device_private(dv);
	int cmd;
	int s;

	s = splhardusb();

	cmd = UREAD2(sc, UHCI_CMD);

#ifdef UHCI_DEBUG
	if (uhcidebug > 2)
		uhci_dumpregs(sc);
#endif
	if (sc->sc_intr_xfer != NULL)
		usb_uncallout(sc->sc_poll_handle, uhci_poll_hub,
		    sc->sc_intr_xfer);
	sc->sc_suspend = PWR_SUSPEND;
	sc->sc_bus.use_polling++;

	uhci_run(sc, 0); /* stop the controller */
	cmd &= ~UHCI_CMD_RS;

	/* save some state if BIOS doesn't */
	sc->sc_saved_frnum = UREAD2(sc, UHCI_FRNUM);
	sc->sc_saved_sof = UREAD1(sc, UHCI_SOF);

	UWRITE2(sc, UHCI_INTR, 0); /* disable intrs */

	UHCICMD(sc, cmd | UHCI_CMD_EGSM); /* enter suspend */
	usb_delay_ms(&sc->sc_bus, USB_RESUME_WAIT);
	sc->sc_bus.use_polling--;

	splx(s);

	return true;
}

#ifdef UHCI_DEBUG
Static void
uhci_dumpregs(uhci_softc_t *sc)
{
	DPRINTFN(-1,("%s regs: cmd=%04x, sts=%04x, intr=%04x, frnum=%04x, "
		     "flbase=%08x, sof=%04x, portsc1=%04x, portsc2=%04x\n",
		     device_xname(sc->sc_dev),
		     UREAD2(sc, UHCI_CMD),
		     UREAD2(sc, UHCI_STS),
		     UREAD2(sc, UHCI_INTR),
		     UREAD2(sc, UHCI_FRNUM),
		     UREAD4(sc, UHCI_FLBASEADDR),
		     UREAD1(sc, UHCI_SOF),
		     UREAD2(sc, UHCI_PORTSC1),
		     UREAD2(sc, UHCI_PORTSC2)));
}

void
uhci_dump_td(uhci_soft_td_t *p)
{
	char sbuf[128], sbuf2[128];


	usb_syncmem(&p->dma, p->offs, sizeof(p->td),
	    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
	DPRINTFN(-1,("TD(%p) at %08lx = link=0x%08lx status=0x%08lx "
		     "token=0x%08lx buffer=0x%08lx\n",
		     p, (long)p->physaddr,
		     (long)le32toh(p->td.td_link),
		     (long)le32toh(p->td.td_status),
		     (long)le32toh(p->td.td_token),
		     (long)le32toh(p->td.td_buffer)));

	snprintb(sbuf, sizeof(sbuf), "\20\1T\2Q\3VF",
	    (u_int32_t)le32toh(p->td.td_link));
	snprintb(sbuf2, sizeof(sbuf2),
	    "\20\22BITSTUFF\23CRCTO\24NAK\25BABBLE\26DBUFFER\27"
	    "STALLED\30ACTIVE\31IOC\32ISO\33LS\36SPD",
	    (u_int32_t)le32toh(p->td.td_status));

	DPRINTFN(-1,("  %s %s,errcnt=%d,actlen=%d pid=%02x,addr=%d,endpt=%d,"
		     "D=%d,maxlen=%d\n", sbuf, sbuf2,
		     UHCI_TD_GET_ERRCNT(le32toh(p->td.td_status)),
		     UHCI_TD_GET_ACTLEN(le32toh(p->td.td_status)),
		     UHCI_TD_GET_PID(le32toh(p->td.td_token)),
		     UHCI_TD_GET_DEVADDR(le32toh(p->td.td_token)),
		     UHCI_TD_GET_ENDPT(le32toh(p->td.td_token)),
		     UHCI_TD_GET_DT(le32toh(p->td.td_token)),
		     UHCI_TD_GET_MAXLEN(le32toh(p->td.td_token))));
	usb_syncmem(&p->dma, p->offs, sizeof(p->td),
	    BUS_DMASYNC_PREREAD);
}

void
uhci_dump_qh(uhci_soft_qh_t *sqh)
{
	usb_syncmem(&sqh->dma, sqh->offs, sizeof(sqh->qh),
	    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
	DPRINTFN(-1,("QH(%p) at %08x: hlink=%08x elink=%08x\n", sqh,
	    (int)sqh->physaddr, le32toh(sqh->qh.qh_hlink),
	    le32toh(sqh->qh.qh_elink)));
	usb_syncmem(&sqh->dma, sqh->offs, sizeof(sqh->qh), BUS_DMASYNC_PREREAD);
}


#if 1
void
uhci_dump(void)
{
	uhci_dump_all(thesc);
}
#endif

void
uhci_dump_all(uhci_softc_t *sc)
{
	uhci_dumpregs(sc);
	printf("intrs=%d\n", sc->sc_bus.no_intrs);
	/*printf("framelist[i].link = %08x\n", sc->sc_framelist[0].link);*/
	uhci_dump_qh(sc->sc_lctl_start);
}


void
uhci_dump_qhs(uhci_soft_qh_t *sqh)
{
	uhci_dump_qh(sqh);

	/* uhci_dump_qhs displays all the QHs and TDs from the given QH onwards
	 * Traverses sideways first, then down.
	 *
	 * QH1
	 * QH2
	 * No QH
	 * TD2.1
	 * TD2.2
	 * TD1.1
	 * etc.
	 *
	 * TD2.x being the TDs queued at QH2 and QH1 being referenced from QH1.
	 */


	usb_syncmem(&sqh->dma, sqh->offs, sizeof(sqh->qh),
	    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
	if (sqh->hlink != NULL && !(le32toh(sqh->qh.qh_hlink) & UHCI_PTR_T))
		uhci_dump_qhs(sqh->hlink);
	else
		DPRINTF(("No QH\n"));
	usb_syncmem(&sqh->dma, sqh->offs, sizeof(sqh->qh), BUS_DMASYNC_PREREAD);

	if (sqh->elink != NULL && !(le32toh(sqh->qh.qh_elink) & UHCI_PTR_T))
		uhci_dump_tds(sqh->elink);
	else
		DPRINTF(("No TD\n"));
}

void
uhci_dump_tds(uhci_soft_td_t *std)
{
	uhci_soft_td_t *td;
	int stop;

	for(td = std; td != NULL; td = td->link.std) {
		uhci_dump_td(td);

		/* Check whether the link pointer in this TD marks
		 * the link pointer as end of queue. This avoids
		 * printing the free list in case the queue/TD has
		 * already been moved there (seatbelt).
		 */
		usb_syncmem(&td->dma, td->offs + offsetof(uhci_td_t, td_link),
		    sizeof(td->td.td_link),
		    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
		stop = (le32toh(td->td.td_link) & UHCI_PTR_T ||
			le32toh(td->td.td_link) == 0);
		usb_syncmem(&td->dma, td->offs + offsetof(uhci_td_t, td_link),
		    sizeof(td->td.td_link), BUS_DMASYNC_PREREAD);
		if (stop)
			break;
	}
}

Static void
uhci_dump_ii(uhci_intr_info_t *ii)
{
	usbd_pipe_handle pipe;
	usb_endpoint_descriptor_t *ed;
	usbd_device_handle dev;

#ifdef DIAGNOSTIC
#define DONE ii->isdone
#else
#define DONE 0
#endif
        if (ii == NULL) {
                printf("ii NULL\n");
                return;
        }
        if (ii->xfer == NULL) {
		printf("ii %p: done=%d xfer=NULL\n",
		       ii, DONE);
                return;
        }
        pipe = ii->xfer->pipe;
        if (pipe == NULL) {
		printf("ii %p: done=%d xfer=%p pipe=NULL\n",
		       ii, DONE, ii->xfer);
                return;
	}
        if (pipe->endpoint == NULL) {
		printf("ii %p: done=%d xfer=%p pipe=%p pipe->endpoint=NULL\n",
		       ii, DONE, ii->xfer, pipe);
                return;
	}
        if (pipe->device == NULL) {
		printf("ii %p: done=%d xfer=%p pipe=%p pipe->device=NULL\n",
		       ii, DONE, ii->xfer, pipe);
                return;
	}
        ed = pipe->endpoint->edesc;
        dev = pipe->device;
	printf("ii %p: done=%d xfer=%p dev=%p vid=0x%04x pid=0x%04x addr=%d pipe=%p ep=0x%02x attr=0x%02x\n",
	       ii, DONE, ii->xfer, dev,
	       UGETW(dev->ddesc.idVendor),
	       UGETW(dev->ddesc.idProduct),
	       dev->address, pipe,
	       ed->bEndpointAddress, ed->bmAttributes);
#undef DONE
}

void uhci_dump_iis(struct uhci_softc *sc);
void
uhci_dump_iis(struct uhci_softc *sc)
{
	uhci_intr_info_t *ii;

	printf("intr_info list:\n");
	for (ii = LIST_FIRST(&sc->sc_intrhead); ii; ii = LIST_NEXT(ii, list))
		uhci_dump_ii(ii);
}

void iidump(void);
void iidump(void) { uhci_dump_iis(thesc); }

#endif

/*
 * This routine is executed periodically and simulates interrupts
 * from the root controller interrupt pipe for port status change.
 */
void
uhci_poll_hub(void *addr)
{
	usbd_xfer_handle xfer = addr;
	usbd_pipe_handle pipe = xfer->pipe;
	uhci_softc_t *sc;
	int s;
	u_char *p;

	DPRINTFN(20, ("uhci_poll_hub\n"));

	if (__predict_false(pipe->device == NULL || pipe->device->bus == NULL))
		return;	/* device has detached */
	sc = pipe->device->bus->hci_private;
	usb_callout(sc->sc_poll_handle, sc->sc_ival, uhci_poll_hub, xfer);

	p = KERNADDR(&xfer->dmabuf, 0);
	p[0] = 0;
	if (UREAD2(sc, UHCI_PORTSC1) & (UHCI_PORTSC_CSC|UHCI_PORTSC_OCIC))
		p[0] |= 1<<1;
	if (UREAD2(sc, UHCI_PORTSC2) & (UHCI_PORTSC_CSC|UHCI_PORTSC_OCIC))
		p[0] |= 1<<2;
	if (p[0] == 0)
		/* No change, try again in a while */
		return;

	xfer->actlen = 1;
	xfer->status = USBD_NORMAL_COMPLETION;
	s = splusb();
	xfer->device->bus->intr_context++;
	usb_transfer_complete(xfer);
	xfer->device->bus->intr_context--;
	splx(s);
}

void
uhci_root_intr_done(usbd_xfer_handle xfer)
{
}

void
uhci_root_ctrl_done(usbd_xfer_handle xfer)
{
}

/*
 * Let the last QH loop back to the high speed control transfer QH.
 * This is what intel calls "bandwidth reclamation" and improves
 * USB performance a lot for some devices.
 * If we are already looping, just count it.
 */
void
uhci_add_loop(uhci_softc_t *sc) {
#ifdef UHCI_DEBUG
	if (uhcinoloop)
		return;
#endif
	if (++sc->sc_loops == 1) {
		DPRINTFN(5,("uhci_start_loop: add\n"));
		/* Note, we don't loop back the soft pointer. */
		sc->sc_last_qh->qh.qh_hlink =
		    htole32(sc->sc_hctl_start->physaddr | UHCI_PTR_QH);
		usb_syncmem(&sc->sc_last_qh->dma,
		    sc->sc_last_qh->offs + offsetof(uhci_qh_t, qh_hlink),
		    sizeof(sc->sc_last_qh->qh.qh_hlink),
		    BUS_DMASYNC_PREWRITE);
	}
}

void
uhci_rem_loop(uhci_softc_t *sc) {
#ifdef UHCI_DEBUG
	if (uhcinoloop)
		return;
#endif
	if (--sc->sc_loops == 0) {
		DPRINTFN(5,("uhci_end_loop: remove\n"));
		sc->sc_last_qh->qh.qh_hlink = htole32(UHCI_PTR_T);
		usb_syncmem(&sc->sc_last_qh->dma,
		    sc->sc_last_qh->offs + offsetof(uhci_qh_t, qh_hlink),
		    sizeof(sc->sc_last_qh->qh.qh_hlink),
		    BUS_DMASYNC_PREWRITE);
	}
}

/* Add high speed control QH, called at splusb(). */
void
uhci_add_hs_ctrl(uhci_softc_t *sc, uhci_soft_qh_t *sqh)
{
	uhci_soft_qh_t *eqh;

	SPLUSBCHECK;

	DPRINTFN(10, ("uhci_add_ctrl: sqh=%p\n", sqh));
	eqh = sc->sc_hctl_end;
	usb_syncmem(&eqh->dma, eqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(eqh->qh.qh_hlink),
	    BUS_DMASYNC_POSTWRITE);
	sqh->hlink       = eqh->hlink;
	sqh->qh.qh_hlink = eqh->qh.qh_hlink;
	usb_syncmem(&sqh->dma, sqh->offs, sizeof(sqh->qh),
	    BUS_DMASYNC_PREWRITE);
	eqh->hlink       = sqh;
	eqh->qh.qh_hlink = htole32(sqh->physaddr | UHCI_PTR_QH);
	sc->sc_hctl_end = sqh;
	usb_syncmem(&eqh->dma, eqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(eqh->qh.qh_hlink), BUS_DMASYNC_PREWRITE);
#ifdef UHCI_CTL_LOOP
	uhci_add_loop(sc);
#endif
}

/* Remove high speed control QH, called at splusb(). */
void
uhci_remove_hs_ctrl(uhci_softc_t *sc, uhci_soft_qh_t *sqh)
{
	uhci_soft_qh_t *pqh;

	SPLUSBCHECK;

	DPRINTFN(10, ("uhci_remove_hs_ctrl: sqh=%p\n", sqh));
#ifdef UHCI_CTL_LOOP
	uhci_rem_loop(sc);
#endif
	/*
	 * The T bit should be set in the elink of the QH so that the HC
	 * doesn't follow the pointer.  This condition may fail if the
	 * the transferred packet was short so that the QH still points
	 * at the last used TD.
	 * In this case we set the T bit and wait a little for the HC
	 * to stop looking at the TD.
	 * Note that if the TD chain is large enough, the controller
	 * may still be looking at the chain at the end of this function.
	 * uhci_free_std_chain() will make sure the controller stops
	 * looking at it quickly, but until then we should not change
	 * sqh->hlink.
	 */
	usb_syncmem(&sqh->dma, sqh->offs + offsetof(uhci_qh_t, qh_elink),
	    sizeof(sqh->qh.qh_elink),
	    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
	if (!(sqh->qh.qh_elink & htole32(UHCI_PTR_T))) {
		sqh->qh.qh_elink = htole32(UHCI_PTR_T);
		usb_syncmem(&sqh->dma,
		    sqh->offs + offsetof(uhci_qh_t, qh_elink),
		    sizeof(sqh->qh.qh_elink),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
		delay(UHCI_QH_REMOVE_DELAY);
	}

	pqh = uhci_find_prev_qh(sc->sc_hctl_start, sqh);
	usb_syncmem(&sqh->dma, sqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(sqh->qh.qh_hlink), BUS_DMASYNC_POSTWRITE);
	pqh->hlink = sqh->hlink;
	pqh->qh.qh_hlink = sqh->qh.qh_hlink;
	usb_syncmem(&pqh->dma, pqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(pqh->qh.qh_hlink),
	    BUS_DMASYNC_PREWRITE);
	delay(UHCI_QH_REMOVE_DELAY);
	if (sc->sc_hctl_end == sqh)
		sc->sc_hctl_end = pqh;
}

/* Add low speed control QH, called at splusb(). */
void
uhci_add_ls_ctrl(uhci_softc_t *sc, uhci_soft_qh_t *sqh)
{
	uhci_soft_qh_t *eqh;

	SPLUSBCHECK;

	DPRINTFN(10, ("uhci_add_ls_ctrl: sqh=%p\n", sqh));
	eqh = sc->sc_lctl_end;
	usb_syncmem(&eqh->dma, eqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(eqh->qh.qh_hlink), BUS_DMASYNC_POSTWRITE);
	sqh->hlink = eqh->hlink;
	sqh->qh.qh_hlink = eqh->qh.qh_hlink;
	usb_syncmem(&sqh->dma, sqh->offs, sizeof(sqh->qh),
	    BUS_DMASYNC_PREWRITE);
	eqh->hlink = sqh;
	eqh->qh.qh_hlink = htole32(sqh->physaddr | UHCI_PTR_QH);
	usb_syncmem(&eqh->dma, eqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(eqh->qh.qh_hlink), BUS_DMASYNC_PREWRITE);
	sc->sc_lctl_end = sqh;
}

/* Remove low speed control QH, called at splusb(). */
void
uhci_remove_ls_ctrl(uhci_softc_t *sc, uhci_soft_qh_t *sqh)
{
	uhci_soft_qh_t *pqh;

	SPLUSBCHECK;

	DPRINTFN(10, ("uhci_remove_ls_ctrl: sqh=%p\n", sqh));
	/* See comment in uhci_remove_hs_ctrl() */
	usb_syncmem(&sqh->dma, sqh->offs + offsetof(uhci_qh_t, qh_elink),
	    sizeof(sqh->qh.qh_elink),
	    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
	if (!(sqh->qh.qh_elink & htole32(UHCI_PTR_T))) {
		sqh->qh.qh_elink = htole32(UHCI_PTR_T);
		usb_syncmem(&sqh->dma,
		    sqh->offs + offsetof(uhci_qh_t, qh_elink),
		    sizeof(sqh->qh.qh_elink),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
		delay(UHCI_QH_REMOVE_DELAY);
	}
	pqh = uhci_find_prev_qh(sc->sc_lctl_start, sqh);
	usb_syncmem(&sqh->dma, sqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(sqh->qh.qh_hlink), BUS_DMASYNC_POSTWRITE);
	pqh->hlink = sqh->hlink;
	pqh->qh.qh_hlink = sqh->qh.qh_hlink;
	usb_syncmem(&pqh->dma, pqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(pqh->qh.qh_hlink),
	    BUS_DMASYNC_PREWRITE);
	delay(UHCI_QH_REMOVE_DELAY);
	if (sc->sc_lctl_end == sqh)
		sc->sc_lctl_end = pqh;
}

/* Add bulk QH, called at splusb(). */
void
uhci_add_bulk(uhci_softc_t *sc, uhci_soft_qh_t *sqh)
{
	uhci_soft_qh_t *eqh;

	SPLUSBCHECK;

	DPRINTFN(10, ("uhci_add_bulk: sqh=%p\n", sqh));
	eqh = sc->sc_bulk_end;
	usb_syncmem(&eqh->dma, eqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(eqh->qh.qh_hlink), BUS_DMASYNC_POSTWRITE);
	sqh->hlink = eqh->hlink;
	sqh->qh.qh_hlink = eqh->qh.qh_hlink;
	usb_syncmem(&sqh->dma, sqh->offs, sizeof(sqh->qh),
	    BUS_DMASYNC_PREWRITE);
	eqh->hlink = sqh;
	eqh->qh.qh_hlink = htole32(sqh->physaddr | UHCI_PTR_QH);
	usb_syncmem(&eqh->dma, eqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(eqh->qh.qh_hlink), BUS_DMASYNC_PREWRITE);
	sc->sc_bulk_end = sqh;
	uhci_add_loop(sc);
}

/* Remove bulk QH, called at splusb(). */
void
uhci_remove_bulk(uhci_softc_t *sc, uhci_soft_qh_t *sqh)
{
	uhci_soft_qh_t *pqh;

	SPLUSBCHECK;

	DPRINTFN(10, ("uhci_remove_bulk: sqh=%p\n", sqh));
	uhci_rem_loop(sc);
	/* See comment in uhci_remove_hs_ctrl() */
	usb_syncmem(&sqh->dma, sqh->offs + offsetof(uhci_qh_t, qh_elink),
	    sizeof(sqh->qh.qh_elink),
	    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
	if (!(sqh->qh.qh_elink & htole32(UHCI_PTR_T))) {
		sqh->qh.qh_elink = htole32(UHCI_PTR_T);
		usb_syncmem(&sqh->dma,
		    sqh->offs + offsetof(uhci_qh_t, qh_elink),
		    sizeof(sqh->qh.qh_elink),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
		delay(UHCI_QH_REMOVE_DELAY);
	}
	pqh = uhci_find_prev_qh(sc->sc_bulk_start, sqh);
	usb_syncmem(&sqh->dma, sqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(sqh->qh.qh_hlink), BUS_DMASYNC_POSTWRITE);
	pqh->hlink       = sqh->hlink;
	pqh->qh.qh_hlink = sqh->qh.qh_hlink;
	usb_syncmem(&pqh->dma, pqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(pqh->qh.qh_hlink), BUS_DMASYNC_PREWRITE);
	delay(UHCI_QH_REMOVE_DELAY);
	if (sc->sc_bulk_end == sqh)
		sc->sc_bulk_end = pqh;
}

Static int uhci_intr1(uhci_softc_t *);

int
uhci_intr(void *arg)
{
	uhci_softc_t *sc = arg;

	if (sc->sc_dying || !device_has_power(sc->sc_dev))
		return (0);

	if (sc->sc_bus.use_polling || UREAD2(sc, UHCI_INTR) == 0) {
#ifdef DIAGNOSTIC
		DPRINTFN(16, ("uhci_intr: ignored interrupt while polling\n"));
#endif
		return (0);
	}

	return (uhci_intr1(sc));
}

int
uhci_intr1(uhci_softc_t *sc)
{
	int status;
	int ack;

#ifdef UHCI_DEBUG
	if (uhcidebug > 15) {
		DPRINTF(("%s: uhci_intr1\n", device_xname(sc->sc_dev)));
		uhci_dumpregs(sc);
	}
#endif

	status = UREAD2(sc, UHCI_STS) & UHCI_STS_ALLINTRS;
	if (status == 0)	/* The interrupt was not for us. */
		return (0);

	if (sc->sc_suspend != PWR_RESUME) {
#ifdef DIAGNOSTIC
		printf("%s: interrupt while not operating ignored\n",
		       device_xname(sc->sc_dev));
#endif
		UWRITE2(sc, UHCI_STS, status); /* acknowledge the ints */
		return (0);
	}

	ack = 0;
	if (status & UHCI_STS_USBINT)
		ack |= UHCI_STS_USBINT;
	if (status & UHCI_STS_USBEI)
		ack |= UHCI_STS_USBEI;
	if (status & UHCI_STS_RD) {
		ack |= UHCI_STS_RD;
#ifdef UHCI_DEBUG
		printf("%s: resume detect\n", device_xname(sc->sc_dev));
#endif
	}
	if (status & UHCI_STS_HSE) {
		ack |= UHCI_STS_HSE;
		printf("%s: host system error\n", device_xname(sc->sc_dev));
	}
	if (status & UHCI_STS_HCPE) {
		ack |= UHCI_STS_HCPE;
		printf("%s: host controller process error\n",
		       device_xname(sc->sc_dev));
	}
	if (status & UHCI_STS_HCH) {
		/* no acknowledge needed */
		if (!sc->sc_dying) {
			printf("%s: host controller halted\n",
			    device_xname(sc->sc_dev));
#ifdef UHCI_DEBUG
			uhci_dump_all(sc);
#endif
		}
		sc->sc_dying = 1;
	}

	if (!ack)
		return (0);	/* nothing to acknowledge */
	UWRITE2(sc, UHCI_STS, ack); /* acknowledge the ints */

	sc->sc_bus.no_intrs++;
	usb_schedsoftintr(&sc->sc_bus);

	DPRINTFN(15, ("%s: uhci_intr: exit\n", device_xname(sc->sc_dev)));

	return (1);
}

void
uhci_softintr(void *v)
{
	struct usbd_bus *bus = v;
	uhci_softc_t *sc = bus->hci_private;
	uhci_intr_info_t *ii, *nextii;

	DPRINTFN(10,("%s: uhci_softintr (%d)\n", device_xname(sc->sc_dev),
		     sc->sc_bus.intr_context));

	sc->sc_bus.intr_context++;

	/*
	 * Interrupts on UHCI really suck.  When the host controller
	 * interrupts because a transfer is completed there is no
	 * way of knowing which transfer it was.  You can scan down
	 * the TDs and QHs of the previous frame to limit the search,
	 * but that assumes that the interrupt was not delayed by more
	 * than 1 ms, which may not always be true (e.g. after debug
	 * output on a slow console).
	 * We scan all interrupt descriptors to see if any have
	 * completed.
	 */
	for (ii = LIST_FIRST(&sc->sc_intrhead); ii; ii = nextii) {
		nextii = LIST_NEXT(ii, list);
		uhci_check_intr(sc, ii);
	}

#ifdef USB_USE_SOFTINTR
	if (sc->sc_softwake) {
		sc->sc_softwake = 0;
		wakeup(&sc->sc_softwake);
	}
#endif /* USB_USE_SOFTINTR */

	sc->sc_bus.intr_context--;
}

/* Check for an interrupt. */
void
uhci_check_intr(uhci_softc_t *sc, uhci_intr_info_t *ii)
{
	uhci_soft_td_t *std, *lstd;
	u_int32_t status;

	DPRINTFN(15, ("uhci_check_intr: ii=%p\n", ii));
#ifdef DIAGNOSTIC
	if (ii == NULL) {
		printf("uhci_check_intr: no ii? %p\n", ii);
		return;
	}
#endif
	if (ii->xfer->status == USBD_CANCELLED ||
	    ii->xfer->status == USBD_TIMEOUT) {
		DPRINTF(("uhci_check_intr: aborted xfer=%p\n", ii->xfer));
		return;
	}

	if (ii->stdstart == NULL)
		return;
	lstd = ii->stdend;
#ifdef DIAGNOSTIC
	if (lstd == NULL) {
		printf("uhci_check_intr: std==0\n");
		return;
	}
#endif
	/*
	 * If the last TD is still active we need to check whether there
	 * is an error somewhere in the middle, or whether there was a
	 * short packet (SPD and not ACTIVE).
	 */
	usb_syncmem(&lstd->dma,
	    lstd->offs + offsetof(uhci_td_t, td_status),
	    sizeof(lstd->td.td_status),
	    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
	if (le32toh(lstd->td.td_status) & UHCI_TD_ACTIVE) {
		DPRINTFN(12, ("uhci_check_intr: active ii=%p\n", ii));
		for (std = ii->stdstart; std != lstd; std = std->link.std) {
			usb_syncmem(&std->dma,
			    std->offs + offsetof(uhci_td_t, td_status),
			    sizeof(std->td.td_status),
			    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
			status = le32toh(std->td.td_status);
			usb_syncmem(&std->dma,
			    std->offs + offsetof(uhci_td_t, td_status),
			    sizeof(std->td.td_status), BUS_DMASYNC_PREREAD);
			/* If there's an active TD the xfer isn't done. */
			if (status & UHCI_TD_ACTIVE)
				break;
			/* Any kind of error makes the xfer done. */
			if (status & UHCI_TD_STALLED)
				goto done;
			/* We want short packets, and it is short: it's done */
			usb_syncmem(&std->dma,
			    std->offs + offsetof(uhci_td_t, td_token),
			    sizeof(std->td.td_token),
			    BUS_DMASYNC_POSTWRITE);
			if ((status & UHCI_TD_SPD) &&
			      UHCI_TD_GET_ACTLEN(status) <
			      UHCI_TD_GET_MAXLEN(le32toh(std->td.td_token)))
				goto done;
		}
		DPRINTFN(12, ("uhci_check_intr: ii=%p std=%p still active\n",
			      ii, ii->stdstart));
		usb_syncmem(&lstd->dma,
		    lstd->offs + offsetof(uhci_td_t, td_status),
		    sizeof(lstd->td.td_status),
		    BUS_DMASYNC_PREREAD);
		return;
	}
 done:
	DPRINTFN(12, ("uhci_check_intr: ii=%p done\n", ii));
	usb_uncallout(ii->xfer->timeout_handle, uhci_timeout, ii);
	uhci_idone(ii);
}

/* Called at splusb() */
void
uhci_idone(uhci_intr_info_t *ii)
{
	usbd_xfer_handle xfer = ii->xfer;
	struct uhci_pipe *upipe = (struct uhci_pipe *)xfer->pipe;
	uhci_soft_td_t *std;
	u_int32_t status = 0, nstatus;
	int actlen;

	DPRINTFN(12, ("uhci_idone: ii=%p\n", ii));
#ifdef DIAGNOSTIC
	{
		int s = splhigh();
		if (ii->isdone) {
			splx(s);
#ifdef UHCI_DEBUG
			printf("uhci_idone: ii is done!\n   ");
			uhci_dump_ii(ii);
#else
			printf("uhci_idone: ii=%p is done!\n", ii);
#endif
			return;
		}
		ii->isdone = 1;
		splx(s);
	}
#endif

	if (xfer->nframes != 0) {
		/* Isoc transfer, do things differently. */
		uhci_soft_td_t **stds = upipe->u.iso.stds;
		int i, n, nframes, len;

		DPRINTFN(5,("uhci_idone: ii=%p isoc ready\n", ii));

		nframes = xfer->nframes;
		actlen = 0;
		n = UXFER(xfer)->curframe;
		for (i = 0; i < nframes; i++) {
			std = stds[n];
#ifdef UHCI_DEBUG
			if (uhcidebug > 5) {
				DPRINTFN(-1,("uhci_idone: isoc TD %d\n", i));
				uhci_dump_td(std);
			}
#endif
			if (++n >= UHCI_VFRAMELIST_COUNT)
				n = 0;
			usb_syncmem(&std->dma,
			    std->offs + offsetof(uhci_td_t, td_status),
			    sizeof(std->td.td_status),
			    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
			status = le32toh(std->td.td_status);
			len = UHCI_TD_GET_ACTLEN(status);
			xfer->frlengths[i] = len;
			actlen += len;
		}
		upipe->u.iso.inuse -= nframes;
		xfer->actlen = actlen;
		xfer->status = USBD_NORMAL_COMPLETION;
		goto end;
	}

#ifdef UHCI_DEBUG
	DPRINTFN(10, ("uhci_idone: ii=%p, xfer=%p, pipe=%p ready\n",
		      ii, xfer, upipe));
	if (uhcidebug > 10)
		uhci_dump_tds(ii->stdstart);
#endif

	/* The transfer is done, compute actual length and status. */
	actlen = 0;
	for (std = ii->stdstart; std != NULL; std = std->link.std) {
		usb_syncmem(&std->dma, std->offs, sizeof(std->td),
		    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
		nstatus = le32toh(std->td.td_status);
		if (nstatus & UHCI_TD_ACTIVE)
			break;

		status = nstatus;
		if (UHCI_TD_GET_PID(le32toh(std->td.td_token)) !=
			UHCI_TD_PID_SETUP)
			actlen += UHCI_TD_GET_ACTLEN(status);
		else {
			/*
			 * UHCI will report CRCTO in addition to a STALL or NAK
			 * for a SETUP transaction.  See section 3.2.2, "TD
			 * CONTROL AND STATUS".
			 */
			if (status & (UHCI_TD_STALLED | UHCI_TD_NAK))
				status &= ~UHCI_TD_CRCTO;
		}
	}
	/* If there are left over TDs we need to update the toggle. */
	if (std != NULL)
		upipe->nexttoggle = UHCI_TD_GET_DT(le32toh(std->td.td_token));

	status &= UHCI_TD_ERROR;
	DPRINTFN(10, ("uhci_idone: actlen=%d, status=0x%x\n",
		      actlen, status));
	xfer->actlen = actlen;
	if (status != 0) {
#ifdef UHCI_DEBUG
		char sbuf[128];

		snprintb(sbuf, sizeof(sbuf),
		    "\20\22BITSTUFF\23CRCTO\24NAK\25"
		    "BABBLE\26DBUFFER\27STALLED\30ACTIVE",(u_int32_t)status);

		DPRINTFN((status == UHCI_TD_STALLED)*10,
			 ("uhci_idone: error, addr=%d, endpt=0x%02x, "
			  "status 0x%s\n",
			  xfer->pipe->device->address,
			  xfer->pipe->endpoint->edesc->bEndpointAddress,
			  sbuf));
#endif

		if (status == UHCI_TD_STALLED)
			xfer->status = USBD_STALLED;
		else
			xfer->status = USBD_IOERROR; /* more info XXX */
	} else {
		xfer->status = USBD_NORMAL_COMPLETION;
	}

 end:
	usb_transfer_complete(xfer);
	DPRINTFN(12, ("uhci_idone: ii=%p done\n", ii));
}

/*
 * Called when a request does not complete.
 */
void
uhci_timeout(void *addr)
{
	uhci_intr_info_t *ii = addr;
	struct uhci_xfer *uxfer = UXFER(ii->xfer);
	struct uhci_pipe *upipe = (struct uhci_pipe *)uxfer->xfer.pipe;
	uhci_softc_t *sc = upipe->pipe.device->bus->hci_private;

	DPRINTF(("uhci_timeout: uxfer=%p\n", uxfer));

	if (sc->sc_dying) {
		uhci_abort_xfer(&uxfer->xfer, USBD_TIMEOUT);
		return;
	}

	/* Execute the abort in a process context. */
	usb_init_task(&uxfer->abort_task, uhci_timeout_task, ii->xfer);
	usb_add_task(uxfer->xfer.pipe->device, &uxfer->abort_task,
	    USB_TASKQ_HC);
}

void
uhci_timeout_task(void *addr)
{
	usbd_xfer_handle xfer = addr;
	int s;

	DPRINTF(("uhci_timeout_task: xfer=%p\n", xfer));

	s = splusb();
	uhci_abort_xfer(xfer, USBD_TIMEOUT);
	splx(s);
}

/*
 * Wait here until controller claims to have an interrupt.
 * Then call uhci_intr and return.  Use timeout to avoid waiting
 * too long.
 * Only used during boot when interrupts are not enabled yet.
 */
void
uhci_waitintr(uhci_softc_t *sc, usbd_xfer_handle xfer)
{
	int timo = xfer->timeout;
	uhci_intr_info_t *ii;

	DPRINTFN(10,("uhci_waitintr: timeout = %dms\n", timo));

	xfer->status = USBD_IN_PROGRESS;
	for (; timo >= 0; timo--) {
		usb_delay_ms(&sc->sc_bus, 1);
		DPRINTFN(20,("uhci_waitintr: 0x%04x\n", UREAD2(sc, UHCI_STS)));
		if (UREAD2(sc, UHCI_STS) & UHCI_STS_USBINT) {
			uhci_intr1(sc);
			if (xfer->status != USBD_IN_PROGRESS)
				return;
		}
	}

	/* Timeout */
	DPRINTF(("uhci_waitintr: timeout\n"));
	for (ii = LIST_FIRST(&sc->sc_intrhead);
	     ii != NULL && ii->xfer != xfer;
	     ii = LIST_NEXT(ii, list))
		;
#ifdef DIAGNOSTIC
	if (ii == NULL)
		panic("uhci_waitintr: lost intr_info");
#endif
	uhci_idone(ii);
}

void
uhci_poll(struct usbd_bus *bus)
{
	uhci_softc_t *sc = bus->hci_private;

	if (UREAD2(sc, UHCI_STS) & UHCI_STS_USBINT)
		uhci_intr1(sc);
}

void
uhci_reset(uhci_softc_t *sc)
{
	int n;

	UHCICMD(sc, UHCI_CMD_HCRESET);
	/* The reset bit goes low when the controller is done. */
	for (n = 0; n < UHCI_RESET_TIMEOUT &&
		    (UREAD2(sc, UHCI_CMD) & UHCI_CMD_HCRESET); n++)
		usb_delay_ms(&sc->sc_bus, 1);
	if (n >= UHCI_RESET_TIMEOUT)
		printf("%s: controller did not reset\n",
		       device_xname(sc->sc_dev));
}

usbd_status
uhci_run(uhci_softc_t *sc, int run)
{
	int s, n, running;
	u_int16_t cmd;

	run = run != 0;
	s = splhardusb();
	DPRINTF(("uhci_run: setting run=%d\n", run));
	cmd = UREAD2(sc, UHCI_CMD);
	if (run)
		cmd |= UHCI_CMD_RS;
	else
		cmd &= ~UHCI_CMD_RS;
	UHCICMD(sc, cmd);
	for(n = 0; n < 10; n++) {
		running = !(UREAD2(sc, UHCI_STS) & UHCI_STS_HCH);
		/* return when we've entered the state we want */
		if (run == running) {
			splx(s);
			DPRINTF(("uhci_run: done cmd=0x%x sts=0x%x\n",
				 UREAD2(sc, UHCI_CMD), UREAD2(sc, UHCI_STS)));
			return (USBD_NORMAL_COMPLETION);
		}
		usb_delay_ms(&sc->sc_bus, 1);
	}
	splx(s);
	printf("%s: cannot %s\n", device_xname(sc->sc_dev),
	       run ? "start" : "stop");
	return (USBD_IOERROR);
}

/*
 * Memory management routines.
 *  uhci_alloc_std allocates TDs
 *  uhci_alloc_sqh allocates QHs
 * These two routines do their own free list management,
 * partly for speed, partly because allocating DMAable memory
 * has page size granularaity so much memory would be wasted if
 * only one TD/QH (32 bytes) was placed in each allocated chunk.
 */

uhci_soft_td_t *
uhci_alloc_std(uhci_softc_t *sc)
{
	uhci_soft_td_t *std;
	usbd_status err;
	int i, offs;
	usb_dma_t dma;

	if (sc->sc_freetds == NULL) {
		DPRINTFN(2,("uhci_alloc_std: allocating chunk\n"));
		err = usb_allocmem(&sc->sc_bus, UHCI_STD_SIZE * UHCI_STD_CHUNK,
			  UHCI_TD_ALIGN, &dma);
		if (err)
			return (0);
		for(i = 0; i < UHCI_STD_CHUNK; i++) {
			offs = i * UHCI_STD_SIZE;
			std = KERNADDR(&dma, offs);
			std->physaddr = DMAADDR(&dma, offs);
			std->dma = dma;
			std->offs = offs;
			std->link.std = sc->sc_freetds;
			sc->sc_freetds = std;
		}
	}
	std = sc->sc_freetds;
	sc->sc_freetds = std->link.std;
	memset(&std->td, 0, sizeof(uhci_td_t));
	return std;
}

void
uhci_free_std(uhci_softc_t *sc, uhci_soft_td_t *std)
{
#ifdef DIAGNOSTIC
#define TD_IS_FREE 0x12345678
	if (le32toh(std->td.td_token) == TD_IS_FREE) {
		printf("uhci_free_std: freeing free TD %p\n", std);
		return;
	}
	std->td.td_token = htole32(TD_IS_FREE);
#endif
	std->link.std = sc->sc_freetds;
	sc->sc_freetds = std;
}

uhci_soft_qh_t *
uhci_alloc_sqh(uhci_softc_t *sc)
{
	uhci_soft_qh_t *sqh;
	usbd_status err;
	int i, offs;
	usb_dma_t dma;

	if (sc->sc_freeqhs == NULL) {
		DPRINTFN(2, ("uhci_alloc_sqh: allocating chunk\n"));
		err = usb_allocmem(&sc->sc_bus, UHCI_SQH_SIZE * UHCI_SQH_CHUNK,
			  UHCI_QH_ALIGN, &dma);
		if (err)
			return (0);
		for(i = 0; i < UHCI_SQH_CHUNK; i++) {
			offs = i * UHCI_SQH_SIZE;
			sqh = KERNADDR(&dma, offs);
			sqh->physaddr = DMAADDR(&dma, offs);
			sqh->dma = dma;
			sqh->offs = offs;
			sqh->hlink = sc->sc_freeqhs;
			sc->sc_freeqhs = sqh;
		}
	}
	sqh = sc->sc_freeqhs;
	sc->sc_freeqhs = sqh->hlink;
	memset(&sqh->qh, 0, sizeof(uhci_qh_t));
	return (sqh);
}

void
uhci_free_sqh(uhci_softc_t *sc, uhci_soft_qh_t *sqh)
{
	sqh->hlink = sc->sc_freeqhs;
	sc->sc_freeqhs = sqh;
}

void
uhci_free_std_chain(uhci_softc_t *sc, uhci_soft_td_t *std,
		    uhci_soft_td_t *stdend)
{
	uhci_soft_td_t *p;

	/*
	 * to avoid race condition with the controller which may be looking
	 * at this chain, we need to first invalidate all links, and
	 * then wait for the controller to move to another queue
	 */
	for (p = std; p != stdend; p = p->link.std) {
		usb_syncmem(&p->dma,
		    p->offs + offsetof(uhci_td_t, td_link),
		    sizeof(p->td.td_link),
		    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
		if ((p->td.td_link & UHCI_PTR_T) == 0) {
			p->td.td_link = UHCI_PTR_T;
			usb_syncmem(&p->dma,
			    p->offs + offsetof(uhci_td_t, td_link),
			    sizeof(p->td.td_link),
			    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
		}
	}
	delay(UHCI_QH_REMOVE_DELAY);

	for (; std != stdend; std = p) {
		p = std->link.std;
		uhci_free_std(sc, std);
	}
}

usbd_status
uhci_alloc_std_chain(struct uhci_pipe *upipe, uhci_softc_t *sc, int len,
		     int rd, u_int16_t flags, usb_dma_t *dma,
		     uhci_soft_td_t **sp, uhci_soft_td_t **ep)
{
	uhci_soft_td_t *p, *lastp;
	uhci_physaddr_t lastlink;
	int i, ntd, l, tog, maxp;
	u_int32_t status;
	int addr = upipe->pipe.device->address;
	int endpt = upipe->pipe.endpoint->edesc->bEndpointAddress;

	DPRINTFN(8, ("uhci_alloc_std_chain: addr=%d endpt=%d len=%d speed=%d "
		      "flags=0x%x\n", addr, UE_GET_ADDR(endpt), len,
		      upipe->pipe.device->speed, flags));
	maxp = UGETW(upipe->pipe.endpoint->edesc->wMaxPacketSize);
	if (maxp == 0) {
		printf("uhci_alloc_std_chain: maxp=0\n");
		return (USBD_INVAL);
	}
	ntd = (len + maxp - 1) / maxp;
	if ((flags & USBD_FORCE_SHORT_XFER) && len % maxp == 0)
		ntd++;
	DPRINTFN(10, ("uhci_alloc_std_chain: maxp=%d ntd=%d\n", maxp, ntd));
	if (ntd == 0) {
		*sp = *ep = 0;
		DPRINTFN(-1,("uhci_alloc_std_chain: ntd=0\n"));
		return (USBD_NORMAL_COMPLETION);
	}
	tog = upipe->nexttoggle;
	if (ntd % 2 == 0)
		tog ^= 1;
	upipe->nexttoggle = tog ^ 1;
	lastp = NULL;
	lastlink = UHCI_PTR_T;
	ntd--;
	status = UHCI_TD_ZERO_ACTLEN(UHCI_TD_SET_ERRCNT(3) | UHCI_TD_ACTIVE);
	if (upipe->pipe.device->speed == USB_SPEED_LOW)
		status |= UHCI_TD_LS;
	if (flags & USBD_SHORT_XFER_OK)
		status |= UHCI_TD_SPD;
	usb_syncmem(dma, 0, len,
	    rd ? BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
	for (i = ntd; i >= 0; i--) {
		p = uhci_alloc_std(sc);
		if (p == NULL) {
			KASSERT(lastp != NULL);
			uhci_free_std_chain(sc, lastp, NULL);
			return (USBD_NOMEM);
		}
		p->link.std = lastp;
		p->td.td_link = htole32(lastlink | UHCI_PTR_VF | UHCI_PTR_TD);
		lastp = p;
		lastlink = p->physaddr;
		p->td.td_status = htole32(status);
		if (i == ntd) {
			/* last TD */
			l = len % maxp;
			if (l == 0 && !(flags & USBD_FORCE_SHORT_XFER))
				l = maxp;
			*ep = p;
		} else
			l = maxp;
		p->td.td_token =
		    htole32(rd ? UHCI_TD_IN (l, endpt, addr, tog) :
				 UHCI_TD_OUT(l, endpt, addr, tog));
		p->td.td_buffer = htole32(DMAADDR(dma, i * maxp));
		usb_syncmem(&p->dma, p->offs, sizeof(p->td),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
		tog ^= 1;
	}
	*sp = lastp;
	DPRINTFN(10, ("uhci_alloc_std_chain: nexttog=%d\n",
		      upipe->nexttoggle));
	return (USBD_NORMAL_COMPLETION);
}

void
uhci_device_clear_toggle(usbd_pipe_handle pipe)
{
	struct uhci_pipe *upipe = (struct uhci_pipe *)pipe;
	upipe->nexttoggle = 0;
}

void
uhci_noop(usbd_pipe_handle pipe)
{
}

usbd_status
uhci_device_bulk_transfer(usbd_xfer_handle xfer)
{
	usbd_status err;

	/* Insert last in queue. */
	err = usb_insert_transfer(xfer);
	if (err)
		return (err);

	/*
	 * Pipe isn't running (otherwise err would be USBD_INPROG),
	 * so start it first.
	 */
	return (uhci_device_bulk_start(SIMPLEQ_FIRST(&xfer->pipe->queue)));
}

usbd_status
uhci_device_bulk_start(usbd_xfer_handle xfer)
{
	struct uhci_pipe *upipe = (struct uhci_pipe *)xfer->pipe;
	usbd_device_handle dev = upipe->pipe.device;
	uhci_softc_t *sc = dev->bus->hci_private;
	uhci_intr_info_t *ii = &UXFER(xfer)->iinfo;
	uhci_soft_td_t *data, *dataend;
	uhci_soft_qh_t *sqh;
	usbd_status err;
	int len, isread, endpt;
	int s;

	DPRINTFN(3, ("uhci_device_bulk_start: xfer=%p len=%d flags=%d ii=%p\n",
		     xfer, xfer->length, xfer->flags, ii));

	if (sc->sc_dying)
		return (USBD_IOERROR);

#ifdef DIAGNOSTIC
	if (xfer->rqflags & URQ_REQUEST)
		panic("uhci_device_bulk_transfer: a request");
#endif

	len = xfer->length;
	endpt = upipe->pipe.endpoint->edesc->bEndpointAddress;
	isread = UE_GET_DIR(endpt) == UE_DIR_IN;
	sqh = upipe->u.bulk.sqh;

	upipe->u.bulk.isread = isread;
	upipe->u.bulk.length = len;

	err = uhci_alloc_std_chain(upipe, sc, len, isread, xfer->flags,
				   &xfer->dmabuf, &data, &dataend);
	if (err)
		return (err);
	dataend->td.td_status |= htole32(UHCI_TD_IOC);
	usb_syncmem(&dataend->dma,
	    dataend->offs + offsetof(uhci_td_t, td_status),
	    sizeof(dataend->td.td_status),
	    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);


#ifdef UHCI_DEBUG
	if (uhcidebug > 8) {
		DPRINTF(("uhci_device_bulk_transfer: data(1)\n"));
		uhci_dump_tds(data);
	}
#endif

	/* Set up interrupt info. */
	ii->xfer = xfer;
	ii->stdstart = data;
	ii->stdend = dataend;
#ifdef DIAGNOSTIC
	if (!ii->isdone) {
		printf("uhci_device_bulk_transfer: not done, ii=%p\n", ii);
	}
	ii->isdone = 0;
#endif

	sqh->elink = data;
	sqh->qh.qh_elink = htole32(data->physaddr | UHCI_PTR_TD);
	/* uhci_add_bulk() will do usb_syncmem(sqh) */

	s = splusb();
	uhci_add_bulk(sc, sqh);
	uhci_add_intr_info(sc, ii);

	if (xfer->timeout && !sc->sc_bus.use_polling) {
		usb_callout(xfer->timeout_handle, mstohz(xfer->timeout),
			    uhci_timeout, ii);
	}
	xfer->status = USBD_IN_PROGRESS;
	splx(s);

#ifdef UHCI_DEBUG
	if (uhcidebug > 10) {
		DPRINTF(("uhci_device_bulk_transfer: data(2)\n"));
		uhci_dump_tds(data);
	}
#endif

	if (sc->sc_bus.use_polling)
		uhci_waitintr(sc, xfer);

	return (USBD_IN_PROGRESS);
}

/* Abort a device bulk request. */
void
uhci_device_bulk_abort(usbd_xfer_handle xfer)
{
	DPRINTF(("uhci_device_bulk_abort:\n"));
	uhci_abort_xfer(xfer, USBD_CANCELLED);
}

/*
 * Abort a device request.
 * If this routine is called at splusb() it guarantees that the request
 * will be removed from the hardware scheduling and that the callback
 * for it will be called with USBD_CANCELLED status.
 * It's impossible to guarantee that the requested transfer will not
 * have happened since the hardware runs concurrently.
 * If the transaction has already happened we rely on the ordinary
 * interrupt processing to process it.
 */
void
uhci_abort_xfer(usbd_xfer_handle xfer, usbd_status status)
{
	uhci_intr_info_t *ii = &UXFER(xfer)->iinfo;
	struct uhci_pipe *upipe = (struct uhci_pipe *)xfer->pipe;
	uhci_softc_t *sc = upipe->pipe.device->bus->hci_private;
	uhci_soft_td_t *std;
	int s;
	int wake;

	DPRINTFN(1,("uhci_abort_xfer: xfer=%p, status=%d\n", xfer, status));

	if (sc->sc_dying) {
		/* If we're dying, just do the software part. */
		s = splusb();
		xfer->status = status;	/* make software ignore it */
		usb_uncallout(xfer->timeout_handle, uhci_timeout, xfer);
		usb_transfer_complete(xfer);
		splx(s);
		return;
	}

	if (xfer->device->bus->intr_context || !curproc)
		panic("uhci_abort_xfer: not in process context");

	/*
	 * If an abort is already in progress then just wait for it to
	 * complete and return.
	 */
	if (xfer->hcflags & UXFER_ABORTING) {
		DPRINTFN(2, ("uhci_abort_xfer: already aborting\n"));
#ifdef DIAGNOSTIC
		if (status == USBD_TIMEOUT)
			printf("uhci_abort_xfer: TIMEOUT while aborting\n");
#endif
		/* Override the status which might be USBD_TIMEOUT. */
		xfer->status = status;
		DPRINTFN(2, ("uhci_abort_xfer: waiting for abort to finish\n"));
		xfer->hcflags |= UXFER_ABORTWAIT;
		while (xfer->hcflags & UXFER_ABORTING)
			tsleep(&xfer->hcflags, PZERO, "uhciaw", 0);
		return;
	}
	xfer->hcflags |= UXFER_ABORTING;

	/*
	 * Step 1: Make interrupt routine and hardware ignore xfer.
	 */
	s = splusb();
	xfer->status = status;	/* make software ignore it */
	usb_uncallout(xfer->timeout_handle, uhci_timeout, ii);
	DPRINTFN(1,("uhci_abort_xfer: stop ii=%p\n", ii));
	for (std = ii->stdstart; std != NULL; std = std->link.std) {
		usb_syncmem(&std->dma,
		    std->offs + offsetof(uhci_td_t, td_status),
		    sizeof(std->td.td_status),
		    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
		std->td.td_status &= htole32(~(UHCI_TD_ACTIVE | UHCI_TD_IOC));
		usb_syncmem(&std->dma,
		    std->offs + offsetof(uhci_td_t, td_status),
		    sizeof(std->td.td_status),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
	}
	splx(s);

	/*
	 * Step 2: Wait until we know hardware has finished any possible
	 * use of the xfer.  Also make sure the soft interrupt routine
	 * has run.
	 */
	usb_delay_ms(upipe->pipe.device->bus, 2); /* Hardware finishes in 1ms */
	s = splusb();
#ifdef USB_USE_SOFTINTR
	sc->sc_softwake = 1;
#endif /* USB_USE_SOFTINTR */
	usb_schedsoftintr(&sc->sc_bus);
#ifdef USB_USE_SOFTINTR
	DPRINTFN(1,("uhci_abort_xfer: tsleep\n"));
	tsleep(&sc->sc_softwake, PZERO, "uhciab", 0);
#endif /* USB_USE_SOFTINTR */
	splx(s);

	/*
	 * Step 3: Execute callback.
	 */
	DPRINTFN(1,("uhci_abort_xfer: callback\n"));
	s = splusb();
#ifdef DIAGNOSTIC
	ii->isdone = 1;
#endif
	wake = xfer->hcflags & UXFER_ABORTWAIT;
	xfer->hcflags &= ~(UXFER_ABORTING | UXFER_ABORTWAIT);
	usb_transfer_complete(xfer);
	if (wake)
		wakeup(&xfer->hcflags);
	splx(s);
}

/* Close a device bulk pipe. */
void
uhci_device_bulk_close(usbd_pipe_handle pipe)
{
	struct uhci_pipe *upipe = (struct uhci_pipe *)pipe;
	usbd_device_handle dev = upipe->pipe.device;
	uhci_softc_t *sc = dev->bus->hci_private;

	uhci_free_sqh(sc, upipe->u.bulk.sqh);
}

usbd_status
uhci_device_ctrl_transfer(usbd_xfer_handle xfer)
{
	usbd_status err;

	/* Insert last in queue. */
	err = usb_insert_transfer(xfer);
	if (err)
		return (err);

	/*
	 * Pipe isn't running (otherwise err would be USBD_INPROG),
	 * so start it first.
	 */
	return (uhci_device_ctrl_start(SIMPLEQ_FIRST(&xfer->pipe->queue)));
}

usbd_status
uhci_device_ctrl_start(usbd_xfer_handle xfer)
{
	uhci_softc_t *sc = xfer->pipe->device->bus->hci_private;
	usbd_status err;

	if (sc->sc_dying)
		return (USBD_IOERROR);

#ifdef DIAGNOSTIC
	if (!(xfer->rqflags & URQ_REQUEST))
		panic("uhci_device_ctrl_transfer: not a request");
#endif

	err = uhci_device_request(xfer);
	if (err)
		return (err);

	if (sc->sc_bus.use_polling)
		uhci_waitintr(sc, xfer);
	return (USBD_IN_PROGRESS);
}

usbd_status
uhci_device_intr_transfer(usbd_xfer_handle xfer)
{
	usbd_status err;

	/* Insert last in queue. */
	err = usb_insert_transfer(xfer);
	if (err)
		return (err);

	/*
	 * Pipe isn't running (otherwise err would be USBD_INPROG),
	 * so start it first.
	 */
	return (uhci_device_intr_start(SIMPLEQ_FIRST(&xfer->pipe->queue)));
}

usbd_status
uhci_device_intr_start(usbd_xfer_handle xfer)
{
	struct uhci_pipe *upipe = (struct uhci_pipe *)xfer->pipe;
	usbd_device_handle dev = upipe->pipe.device;
	uhci_softc_t *sc = dev->bus->hci_private;
	uhci_intr_info_t *ii = &UXFER(xfer)->iinfo;
	uhci_soft_td_t *data, *dataend;
	uhci_soft_qh_t *sqh;
	usbd_status err;
	int isread, endpt;
	int i, s;

	if (sc->sc_dying)
		return (USBD_IOERROR);

	DPRINTFN(3,("uhci_device_intr_transfer: xfer=%p len=%d flags=%d\n",
		    xfer, xfer->length, xfer->flags));

#ifdef DIAGNOSTIC
	if (xfer->rqflags & URQ_REQUEST)
		panic("uhci_device_intr_transfer: a request");
#endif

	endpt = upipe->pipe.endpoint->edesc->bEndpointAddress;
	isread = UE_GET_DIR(endpt) == UE_DIR_IN;

	upipe->u.intr.isread = isread;

	err = uhci_alloc_std_chain(upipe, sc, xfer->length, isread,
				   xfer->flags, &xfer->dmabuf, &data,
				   &dataend);
	if (err)
		return (err);
	dataend->td.td_status |= htole32(UHCI_TD_IOC);
	usb_syncmem(&dataend->dma,
	    dataend->offs + offsetof(uhci_td_t, td_status),
	    sizeof(dataend->td.td_status),
	    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);

#ifdef UHCI_DEBUG
	if (uhcidebug > 10) {
		DPRINTF(("uhci_device_intr_transfer: data(1)\n"));
		uhci_dump_tds(data);
		uhci_dump_qh(upipe->u.intr.qhs[0]);
	}
#endif

	s = splusb();
	/* Set up interrupt info. */
	ii->xfer = xfer;
	ii->stdstart = data;
	ii->stdend = dataend;
#ifdef DIAGNOSTIC
	if (!ii->isdone) {
		printf("uhci_device_intr_transfer: not done, ii=%p\n", ii);
	}
	ii->isdone = 0;
#endif

	DPRINTFN(10,("uhci_device_intr_transfer: qhs[0]=%p\n",
		     upipe->u.intr.qhs[0]));
	for (i = 0; i < upipe->u.intr.npoll; i++) {
		sqh = upipe->u.intr.qhs[i];
		sqh->elink = data;
		sqh->qh.qh_elink = htole32(data->physaddr | UHCI_PTR_TD);
		usb_syncmem(&sqh->dma,
		    sqh->offs + offsetof(uhci_qh_t, qh_elink),
		    sizeof(sqh->qh.qh_elink),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
	}
	uhci_add_intr_info(sc, ii);
	xfer->status = USBD_IN_PROGRESS;
	splx(s);

#ifdef UHCI_DEBUG
	if (uhcidebug > 10) {
		DPRINTF(("uhci_device_intr_transfer: data(2)\n"));
		uhci_dump_tds(data);
		uhci_dump_qh(upipe->u.intr.qhs[0]);
	}
#endif

	return (USBD_IN_PROGRESS);
}

/* Abort a device control request. */
void
uhci_device_ctrl_abort(usbd_xfer_handle xfer)
{
	DPRINTF(("uhci_device_ctrl_abort:\n"));
	uhci_abort_xfer(xfer, USBD_CANCELLED);
}

/* Close a device control pipe. */
void
uhci_device_ctrl_close(usbd_pipe_handle pipe)
{
}

/* Abort a device interrupt request. */
void
uhci_device_intr_abort(usbd_xfer_handle xfer)
{
	DPRINTFN(1,("uhci_device_intr_abort: xfer=%p\n", xfer));
	if (xfer->pipe->intrxfer == xfer) {
		DPRINTFN(1,("uhci_device_intr_abort: remove\n"));
		xfer->pipe->intrxfer = NULL;
	}
	uhci_abort_xfer(xfer, USBD_CANCELLED);
}

/* Close a device interrupt pipe. */
void
uhci_device_intr_close(usbd_pipe_handle pipe)
{
	struct uhci_pipe *upipe = (struct uhci_pipe *)pipe;
	uhci_softc_t *sc = pipe->device->bus->hci_private;
	int i, npoll;
	int s;

	/* Unlink descriptors from controller data structures. */
	npoll = upipe->u.intr.npoll;
	s = splusb();
	for (i = 0; i < npoll; i++)
		uhci_remove_intr(sc, upipe->u.intr.qhs[i]);
	splx(s);

	/*
	 * We now have to wait for any activity on the physical
	 * descriptors to stop.
	 */
	usb_delay_ms(&sc->sc_bus, 2);

	for(i = 0; i < npoll; i++)
		uhci_free_sqh(sc, upipe->u.intr.qhs[i]);
	free(upipe->u.intr.qhs, M_USBHC);

	/* XXX free other resources */
}

usbd_status
uhci_device_request(usbd_xfer_handle xfer)
{
	struct uhci_pipe *upipe = (struct uhci_pipe *)xfer->pipe;
	usb_device_request_t *req = &xfer->request;
	usbd_device_handle dev = upipe->pipe.device;
	uhci_softc_t *sc = dev->bus->hci_private;
	int addr = dev->address;
	int endpt = upipe->pipe.endpoint->edesc->bEndpointAddress;
	uhci_intr_info_t *ii = &UXFER(xfer)->iinfo;
	uhci_soft_td_t *setup, *data, *stat, *next, *dataend;
	uhci_soft_qh_t *sqh;
	int len;
	u_int32_t ls;
	usbd_status err;
	int isread;
	int s;

	DPRINTFN(3,("uhci_device_control type=0x%02x, request=0x%02x, "
		    "wValue=0x%04x, wIndex=0x%04x len=%d, addr=%d, endpt=%d\n",
		    req->bmRequestType, req->bRequest, UGETW(req->wValue),
		    UGETW(req->wIndex), UGETW(req->wLength),
		    addr, endpt));

	ls = dev->speed == USB_SPEED_LOW ? UHCI_TD_LS : 0;
	isread = req->bmRequestType & UT_READ;
	len = UGETW(req->wLength);

	setup = upipe->u.ctl.setup;
	stat = upipe->u.ctl.stat;
	sqh = upipe->u.ctl.sqh;

	/* Set up data transaction */
	if (len != 0) {
		upipe->nexttoggle = 1;
		err = uhci_alloc_std_chain(upipe, sc, len, isread, xfer->flags,
					   &xfer->dmabuf, &data, &dataend);
		if (err)
			return (err);
		next = data;
		dataend->link.std = stat;
		dataend->td.td_link = htole32(stat->physaddr | UHCI_PTR_VF | UHCI_PTR_TD);
		usb_syncmem(&dataend->dma,
		    dataend->offs + offsetof(uhci_td_t, td_link),
		    sizeof(dataend->td.td_link),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
	} else {
		next = stat;
	}
	upipe->u.ctl.length = len;

	memcpy(KERNADDR(&upipe->u.ctl.reqdma, 0), req, sizeof *req);
	usb_syncmem(&upipe->u.ctl.reqdma, 0, sizeof *req, BUS_DMASYNC_PREWRITE);

	setup->link.std = next;
	setup->td.td_link = htole32(next->physaddr | UHCI_PTR_VF | UHCI_PTR_TD);
	setup->td.td_status = htole32(UHCI_TD_SET_ERRCNT(3) | ls |
		UHCI_TD_ACTIVE);
	setup->td.td_token = htole32(UHCI_TD_SETUP(sizeof *req, endpt, addr));
	setup->td.td_buffer = htole32(DMAADDR(&upipe->u.ctl.reqdma, 0));
	usb_syncmem(&setup->dma, setup->offs, sizeof(setup->td),
	    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);

	stat->link.std = NULL;
	stat->td.td_link = htole32(UHCI_PTR_T);
	stat->td.td_status = htole32(UHCI_TD_SET_ERRCNT(3) | ls |
		UHCI_TD_ACTIVE | UHCI_TD_IOC);
	stat->td.td_token =
		htole32(isread ? UHCI_TD_OUT(0, endpt, addr, 1) :
		                 UHCI_TD_IN (0, endpt, addr, 1));
	stat->td.td_buffer = htole32(0);
	usb_syncmem(&stat->dma, stat->offs, sizeof(stat->td),
	    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);

#ifdef UHCI_DEBUG
	if (uhcidebug > 10) {
		DPRINTF(("uhci_device_request: before transfer\n"));
		uhci_dump_tds(setup);
	}
#endif

	/* Set up interrupt info. */
	ii->xfer = xfer;
	ii->stdstart = setup;
	ii->stdend = stat;
#ifdef DIAGNOSTIC
	if (!ii->isdone) {
		printf("uhci_device_request: not done, ii=%p\n", ii);
	}
	ii->isdone = 0;
#endif

	sqh->elink = setup;
	sqh->qh.qh_elink = htole32(setup->physaddr | UHCI_PTR_TD);
	/* uhci_add_?s_ctrl() will do usb_syncmem(sqh) */

	s = splusb();
	if (dev->speed == USB_SPEED_LOW)
		uhci_add_ls_ctrl(sc, sqh);
	else
		uhci_add_hs_ctrl(sc, sqh);
	uhci_add_intr_info(sc, ii);
#ifdef UHCI_DEBUG
	if (uhcidebug > 12) {
		uhci_soft_td_t *std;
		uhci_soft_qh_t *xqh;
		uhci_soft_qh_t *sxqh;
		int maxqh = 0;
		uhci_physaddr_t link;
		DPRINTF(("uhci_enter_ctl_q: follow from [0]\n"));
		for (std = sc->sc_vframes[0].htd, link = 0;
		     (link & UHCI_PTR_QH) == 0;
		     std = std->link.std) {
			link = le32toh(std->td.td_link);
			uhci_dump_td(std);
		}
		sxqh = (uhci_soft_qh_t *)std;
		uhci_dump_qh(sxqh);
		for (xqh = sxqh;
		     xqh != NULL;
		     xqh = (maxqh++ == 5 || xqh->hlink == sxqh ||
                            xqh->hlink == xqh ? NULL : xqh->hlink)) {
			uhci_dump_qh(xqh);
		}
		DPRINTF(("Enqueued QH:\n"));
		uhci_dump_qh(sqh);
		uhci_dump_tds(sqh->elink);
	}
#endif
	if (xfer->timeout && !sc->sc_bus.use_polling) {
		usb_callout(xfer->timeout_handle, mstohz(xfer->timeout),
			    uhci_timeout, ii);
	}
	xfer->status = USBD_IN_PROGRESS;
	splx(s);

	return (USBD_NORMAL_COMPLETION);
}

usbd_status
uhci_device_isoc_transfer(usbd_xfer_handle xfer)
{
	usbd_status err;

	DPRINTFN(5,("uhci_device_isoc_transfer: xfer=%p\n", xfer));

	/* Put it on our queue, */
	err = usb_insert_transfer(xfer);

	/* bail out on error, */
	if (err && err != USBD_IN_PROGRESS)
		return (err);

	/* XXX should check inuse here */

	/* insert into schedule, */
	uhci_device_isoc_enter(xfer);

	/* and start if the pipe wasn't running */
	if (!err)
		uhci_device_isoc_start(SIMPLEQ_FIRST(&xfer->pipe->queue));

	return (err);
}

void
uhci_device_isoc_enter(usbd_xfer_handle xfer)
{
	struct uhci_pipe *upipe = (struct uhci_pipe *)xfer->pipe;
	usbd_device_handle dev = upipe->pipe.device;
	uhci_softc_t *sc = dev->bus->hci_private;
	struct iso *iso = &upipe->u.iso;
	uhci_soft_td_t *std;
	u_int32_t buf, len, status, offs;
	int s, i, next, nframes;
	int rd = UE_GET_DIR(upipe->pipe.endpoint->edesc->bEndpointAddress) == UE_DIR_IN;

	DPRINTFN(5,("uhci_device_isoc_enter: used=%d next=%d xfer=%p "
		    "nframes=%d\n",
		    iso->inuse, iso->next, xfer, xfer->nframes));

	if (sc->sc_dying)
		return;

	if (xfer->status == USBD_IN_PROGRESS) {
		/* This request has already been entered into the frame list */
		printf("uhci_device_isoc_enter: xfer=%p in frame list\n", xfer);
		/* XXX */
	}

#ifdef DIAGNOSTIC
	if (iso->inuse >= UHCI_VFRAMELIST_COUNT)
		printf("uhci_device_isoc_enter: overflow!\n");
#endif

	next = iso->next;
	if (next == -1) {
		/* Not in use yet, schedule it a few frames ahead. */
		next = (UREAD2(sc, UHCI_FRNUM) + 3) % UHCI_VFRAMELIST_COUNT;
		DPRINTFN(2,("uhci_device_isoc_enter: start next=%d\n", next));
	}

	xfer->status = USBD_IN_PROGRESS;
	UXFER(xfer)->curframe = next;

	buf = DMAADDR(&xfer->dmabuf, 0);
	offs = 0;
	status = UHCI_TD_ZERO_ACTLEN(UHCI_TD_SET_ERRCNT(0) |
				     UHCI_TD_ACTIVE |
				     UHCI_TD_IOS);
	nframes = xfer->nframes;
	s = splusb();
	for (i = 0; i < nframes; i++) {
		std = iso->stds[next];
		if (++next >= UHCI_VFRAMELIST_COUNT)
			next = 0;
		len = xfer->frlengths[i];
		std->td.td_buffer = htole32(buf);
		usb_syncmem(&xfer->dmabuf, offs, len,
		    rd ? BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
		if (i == nframes - 1)
			status |= UHCI_TD_IOC;
		std->td.td_status = htole32(status);
		std->td.td_token &= htole32(~UHCI_TD_MAXLEN_MASK);
		std->td.td_token |= htole32(UHCI_TD_SET_MAXLEN(len));
		usb_syncmem(&std->dma, std->offs, sizeof(std->td),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
#ifdef UHCI_DEBUG
		if (uhcidebug > 5) {
			DPRINTFN(5,("uhci_device_isoc_enter: TD %d\n", i));
			uhci_dump_td(std);
		}
#endif
		buf += len;
		offs += len;
	}
	iso->next = next;
	iso->inuse += xfer->nframes;

	splx(s);
}

usbd_status
uhci_device_isoc_start(usbd_xfer_handle xfer)
{
	struct uhci_pipe *upipe = (struct uhci_pipe *)xfer->pipe;
	uhci_softc_t *sc = upipe->pipe.device->bus->hci_private;
	uhci_intr_info_t *ii = &UXFER(xfer)->iinfo;
	uhci_soft_td_t *end;
	int s, i;

	DPRINTFN(5,("uhci_device_isoc_start: xfer=%p\n", xfer));

	if (sc->sc_dying)
		return (USBD_IOERROR);

#ifdef DIAGNOSTIC
	if (xfer->status != USBD_IN_PROGRESS)
		printf("uhci_device_isoc_start: not in progress %p\n", xfer);
#endif

	/* Find the last TD */
	i = UXFER(xfer)->curframe + xfer->nframes;
	if (i >= UHCI_VFRAMELIST_COUNT)
		i -= UHCI_VFRAMELIST_COUNT;
	end = upipe->u.iso.stds[i];

#ifdef DIAGNOSTIC
	if (end == NULL) {
		printf("uhci_device_isoc_start: end == NULL\n");
		return (USBD_INVAL);
	}
#endif

	s = splusb();

	/* Set up interrupt info. */
	ii->xfer = xfer;
	ii->stdstart = end;
	ii->stdend = end;
#ifdef DIAGNOSTIC
	if (!ii->isdone)
		printf("uhci_device_isoc_start: not done, ii=%p\n", ii);
	ii->isdone = 0;
#endif
	uhci_add_intr_info(sc, ii);

	splx(s);

	return (USBD_IN_PROGRESS);
}

void
uhci_device_isoc_abort(usbd_xfer_handle xfer)
{
	struct uhci_pipe *upipe = (struct uhci_pipe *)xfer->pipe;
	uhci_soft_td_t **stds = upipe->u.iso.stds;
	uhci_soft_td_t *std;
	int i, n, s, nframes, maxlen, len;

	s = splusb();

	/* Transfer is already done. */
	if (xfer->status != USBD_NOT_STARTED &&
	    xfer->status != USBD_IN_PROGRESS) {
		splx(s);
		return;
	}

	/* Give xfer the requested abort code. */
	xfer->status = USBD_CANCELLED;

	/* make hardware ignore it, */
	nframes = xfer->nframes;
	n = UXFER(xfer)->curframe;
	maxlen = 0;
	for (i = 0; i < nframes; i++) {
		std = stds[n];
		usb_syncmem(&std->dma,
		    std->offs + offsetof(uhci_td_t, td_status),
		    sizeof(std->td.td_status),
		    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
		std->td.td_status &= htole32(~(UHCI_TD_ACTIVE | UHCI_TD_IOC));
		usb_syncmem(&std->dma,
		    std->offs + offsetof(uhci_td_t, td_status),
		    sizeof(std->td.td_status),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
		usb_syncmem(&std->dma,
		    std->offs + offsetof(uhci_td_t, td_token),
		    sizeof(std->td.td_token),
		    BUS_DMASYNC_POSTWRITE);
		len = UHCI_TD_GET_MAXLEN(le32toh(std->td.td_token));
		if (len > maxlen)
			maxlen = len;
		if (++n >= UHCI_VFRAMELIST_COUNT)
			n = 0;
	}

	/* and wait until we are sure the hardware has finished. */
	delay(maxlen);

#ifdef DIAGNOSTIC
	UXFER(xfer)->iinfo.isdone = 1;
#endif
	/* Run callback and remove from interrupt list. */
	usb_transfer_complete(xfer);

	splx(s);
}

void
uhci_device_isoc_close(usbd_pipe_handle pipe)
{
	struct uhci_pipe *upipe = (struct uhci_pipe *)pipe;
	usbd_device_handle dev = upipe->pipe.device;
	uhci_softc_t *sc = dev->bus->hci_private;
	uhci_soft_td_t *std, *vstd;
	struct iso *iso;
	int i, s;

	/*
	 * Make sure all TDs are marked as inactive.
	 * Wait for completion.
	 * Unschedule.
	 * Deallocate.
	 */
	iso = &upipe->u.iso;

	for (i = 0; i < UHCI_VFRAMELIST_COUNT; i++) {
		std = iso->stds[i];
		usb_syncmem(&std->dma,
		    std->offs + offsetof(uhci_td_t, td_status),
		    sizeof(std->td.td_status),
		    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
		std->td.td_status &= htole32(~UHCI_TD_ACTIVE);
		usb_syncmem(&std->dma,
		    std->offs + offsetof(uhci_td_t, td_status),
		    sizeof(std->td.td_status),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
	}
	usb_delay_ms(&sc->sc_bus, 2); /* wait for completion */

	s = splusb();
	for (i = 0; i < UHCI_VFRAMELIST_COUNT; i++) {
		std = iso->stds[i];
		for (vstd = sc->sc_vframes[i].htd;
		     vstd != NULL && vstd->link.std != std;
		     vstd = vstd->link.std)
			;
		if (vstd == NULL) {
			/*panic*/
			printf("uhci_device_isoc_close: %p not found\n", std);
			splx(s);
			return;
		}
		vstd->link = std->link;
		usb_syncmem(&std->dma,
		    std->offs + offsetof(uhci_td_t, td_link),
		    sizeof(std->td.td_link),
		    BUS_DMASYNC_POSTWRITE);
		vstd->td.td_link = std->td.td_link;
		usb_syncmem(&vstd->dma,
		    vstd->offs + offsetof(uhci_td_t, td_link),
		    sizeof(vstd->td.td_link),
		    BUS_DMASYNC_PREWRITE);
		uhci_free_std(sc, std);
	}
	splx(s);

	free(iso->stds, M_USBHC);
}

usbd_status
uhci_setup_isoc(usbd_pipe_handle pipe)
{
	struct uhci_pipe *upipe = (struct uhci_pipe *)pipe;
	usbd_device_handle dev = upipe->pipe.device;
	uhci_softc_t *sc = dev->bus->hci_private;
	int addr = upipe->pipe.device->address;
	int endpt = upipe->pipe.endpoint->edesc->bEndpointAddress;
	int rd = UE_GET_DIR(endpt) == UE_DIR_IN;
	uhci_soft_td_t *std, *vstd;
	u_int32_t token;
	struct iso *iso;
	int i, s;

	iso = &upipe->u.iso;
	iso->stds = malloc(UHCI_VFRAMELIST_COUNT * sizeof (uhci_soft_td_t *),
			   M_USBHC, M_WAITOK);

	token = rd ? UHCI_TD_IN (0, endpt, addr, 0) :
		     UHCI_TD_OUT(0, endpt, addr, 0);

	/* Allocate the TDs and mark as inactive; */
	for (i = 0; i < UHCI_VFRAMELIST_COUNT; i++) {
		std = uhci_alloc_std(sc);
		if (std == 0)
			goto bad;
		std->td.td_status = htole32(UHCI_TD_IOS); /* iso, inactive */
		std->td.td_token = htole32(token);
		usb_syncmem(&std->dma, std->offs, sizeof(std->td),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
		iso->stds[i] = std;
	}

	/* Insert TDs into schedule. */
	s = splusb();
	for (i = 0; i < UHCI_VFRAMELIST_COUNT; i++) {
		std = iso->stds[i];
		vstd = sc->sc_vframes[i].htd;
		usb_syncmem(&vstd->dma,
		    vstd->offs + offsetof(uhci_td_t, td_link),
		    sizeof(vstd->td.td_link),
		    BUS_DMASYNC_POSTWRITE);
		std->link = vstd->link;
		std->td.td_link = vstd->td.td_link;
		usb_syncmem(&std->dma,
		    std->offs + offsetof(uhci_td_t, td_link),
		    sizeof(std->td.td_link),
		    BUS_DMASYNC_PREWRITE);
		vstd->link.std = std;
		vstd->td.td_link = htole32(std->physaddr | UHCI_PTR_TD);
		usb_syncmem(&vstd->dma,
		    vstd->offs + offsetof(uhci_td_t, td_link),
		    sizeof(vstd->td.td_link),
		    BUS_DMASYNC_PREWRITE);
	}
	splx(s);

	iso->next = -1;
	iso->inuse = 0;

	return (USBD_NORMAL_COMPLETION);

 bad:
	while (--i >= 0)
		uhci_free_std(sc, iso->stds[i]);
	free(iso->stds, M_USBHC);
	return (USBD_NOMEM);
}

void
uhci_device_isoc_done(usbd_xfer_handle xfer)
{
	uhci_intr_info_t *ii = &UXFER(xfer)->iinfo;
	struct uhci_pipe *upipe = (struct uhci_pipe *)xfer->pipe;
	int i, offs;
	int rd = UE_GET_DIR(upipe->pipe.endpoint->edesc->bEndpointAddress) == UE_DIR_IN;


	DPRINTFN(4, ("uhci_isoc_done: length=%d, busy_free=0x%08x\n",
			xfer->actlen, xfer->busy_free));

	if (ii->xfer != xfer)
		/* Not on interrupt list, ignore it. */
		return;

	if (!uhci_active_intr_info(ii))
		return;

#ifdef DIAGNOSTIC
        if (ii->stdend == NULL) {
                printf("uhci_device_isoc_done: xfer=%p stdend==NULL\n", xfer);
#ifdef UHCI_DEBUG
		uhci_dump_ii(ii);
#endif
		return;
	}
#endif

	/* Turn off the interrupt since it is active even if the TD is not. */
	usb_syncmem(&ii->stdend->dma,
	    ii->stdend->offs + offsetof(uhci_td_t, td_status),
	    sizeof(ii->stdend->td.td_status),
	    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
	ii->stdend->td.td_status &= htole32(~UHCI_TD_IOC);
	usb_syncmem(&ii->stdend->dma,
	    ii->stdend->offs + offsetof(uhci_td_t, td_status),
	    sizeof(ii->stdend->td.td_status),
	    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);

	uhci_del_intr_info(ii);	/* remove from active list */

	offs = 0;
	for (i = 0; i < xfer->nframes; i++) {
		usb_syncmem(&xfer->dmabuf, offs, xfer->frlengths[i],
		    rd ? BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
		offs += xfer->frlengths[i];
	}
}

void
uhci_device_intr_done(usbd_xfer_handle xfer)
{
	uhci_intr_info_t *ii = &UXFER(xfer)->iinfo;
	uhci_softc_t *sc = ii->sc;
	struct uhci_pipe *upipe = (struct uhci_pipe *)xfer->pipe;
	uhci_soft_qh_t *sqh;
	int i, npoll, isread;

	DPRINTFN(5, ("uhci_device_intr_done: length=%d\n", xfer->actlen));

	npoll = upipe->u.intr.npoll;
	for(i = 0; i < npoll; i++) {
		sqh = upipe->u.intr.qhs[i];
		sqh->elink = NULL;
		sqh->qh.qh_elink = htole32(UHCI_PTR_T);
		usb_syncmem(&sqh->dma,
		    sqh->offs + offsetof(uhci_qh_t, qh_elink),
		    sizeof(sqh->qh.qh_elink),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
	}
	uhci_free_std_chain(sc, ii->stdstart, NULL);

	isread = UE_GET_DIR(upipe->pipe.endpoint->edesc->bEndpointAddress) == UE_DIR_IN;
	usb_syncmem(&xfer->dmabuf, 0, xfer->length,
	    isread ? BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);

	/* XXX Wasteful. */
	if (xfer->pipe->repeat) {
		uhci_soft_td_t *data, *dataend;

		DPRINTFN(5,("uhci_device_intr_done: requeing\n"));

		/* This alloc cannot fail since we freed the chain above. */
		uhci_alloc_std_chain(upipe, sc, xfer->length,
				     upipe->u.intr.isread, xfer->flags,
				     &xfer->dmabuf, &data, &dataend);
		dataend->td.td_status |= htole32(UHCI_TD_IOC);
		usb_syncmem(&dataend->dma,
		    dataend->offs + offsetof(uhci_td_t, td_status),
		    sizeof(dataend->td.td_status),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);

#ifdef UHCI_DEBUG
		if (uhcidebug > 10) {
			DPRINTF(("uhci_device_intr_done: data(1)\n"));
			uhci_dump_tds(data);
			uhci_dump_qh(upipe->u.intr.qhs[0]);
		}
#endif

		ii->stdstart = data;
		ii->stdend = dataend;
#ifdef DIAGNOSTIC
		if (!ii->isdone) {
			printf("uhci_device_intr_done: not done, ii=%p\n", ii);
		}
		ii->isdone = 0;
#endif
		for (i = 0; i < npoll; i++) {
			sqh = upipe->u.intr.qhs[i];
			sqh->elink = data;
			sqh->qh.qh_elink = htole32(data->physaddr | UHCI_PTR_TD);
			usb_syncmem(&sqh->dma,
			    sqh->offs + offsetof(uhci_qh_t, qh_elink),
			    sizeof(sqh->qh.qh_elink),
			    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
		}
		xfer->status = USBD_IN_PROGRESS;
		/* The ii is already on the examined list, just leave it. */
	} else {
		DPRINTFN(5,("uhci_device_intr_done: removing\n"));
		if (uhci_active_intr_info(ii))
			uhci_del_intr_info(ii);
	}
}

/* Deallocate request data structures */
void
uhci_device_ctrl_done(usbd_xfer_handle xfer)
{
	uhci_intr_info_t *ii = &UXFER(xfer)->iinfo;
	uhci_softc_t *sc = ii->sc;
	struct uhci_pipe *upipe = (struct uhci_pipe *)xfer->pipe;
	int len = UGETW(xfer->request.wLength);
	int isread = (xfer->request.bmRequestType & UT_READ);

#ifdef DIAGNOSTIC
	if (!(xfer->rqflags & URQ_REQUEST))
		panic("uhci_device_ctrl_done: not a request");
#endif

	if (!uhci_active_intr_info(ii))
		return;

	uhci_del_intr_info(ii);	/* remove from active list */

	if (upipe->pipe.device->speed == USB_SPEED_LOW)
		uhci_remove_ls_ctrl(sc, upipe->u.ctl.sqh);
	else
		uhci_remove_hs_ctrl(sc, upipe->u.ctl.sqh);

	if (upipe->u.ctl.length != 0)
		uhci_free_std_chain(sc, ii->stdstart->link.std, ii->stdend);

	if (len) {
		usb_syncmem(&xfer->dmabuf, 0, len,
		    isread ? BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
	}
	usb_syncmem(&upipe->u.ctl.reqdma, 0,
	    sizeof(usb_device_request_t),  BUS_DMASYNC_POSTWRITE);

	DPRINTFN(5, ("uhci_device_ctrl_done: length=%d\n", xfer->actlen));
}

/* Deallocate request data structures */
void
uhci_device_bulk_done(usbd_xfer_handle xfer)
{
	uhci_intr_info_t *ii = &UXFER(xfer)->iinfo;
	uhci_softc_t *sc = ii->sc;
	struct uhci_pipe *upipe = (struct uhci_pipe *)xfer->pipe;

	DPRINTFN(5,("uhci_device_bulk_done: xfer=%p ii=%p sc=%p upipe=%p\n",
		    xfer, ii, sc, upipe));

	if (!uhci_active_intr_info(ii))
		return;

	uhci_del_intr_info(ii);	/* remove from active list */

	uhci_remove_bulk(sc, upipe->u.bulk.sqh);

	uhci_free_std_chain(sc, ii->stdstart, NULL);

	DPRINTFN(5, ("uhci_device_bulk_done: length=%d\n", xfer->actlen));
}

/* Add interrupt QH, called with vflock. */
void
uhci_add_intr(uhci_softc_t *sc, uhci_soft_qh_t *sqh)
{
	struct uhci_vframe *vf = &sc->sc_vframes[sqh->pos];
	uhci_soft_qh_t *eqh;

	DPRINTFN(4, ("uhci_add_intr: n=%d sqh=%p\n", sqh->pos, sqh));

	eqh = vf->eqh;
	usb_syncmem(&eqh->dma, eqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(eqh->qh.qh_hlink),
	    BUS_DMASYNC_POSTWRITE);
	sqh->hlink       = eqh->hlink;
	sqh->qh.qh_hlink = eqh->qh.qh_hlink;
	usb_syncmem(&sqh->dma, sqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(sqh->qh.qh_hlink),
	    BUS_DMASYNC_PREWRITE);
	eqh->hlink       = sqh;
	eqh->qh.qh_hlink = htole32(sqh->physaddr | UHCI_PTR_QH);
	usb_syncmem(&eqh->dma, eqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(eqh->qh.qh_hlink),
	    BUS_DMASYNC_PREWRITE);
	vf->eqh = sqh;
	vf->bandwidth++;
}

/* Remove interrupt QH. */
void
uhci_remove_intr(uhci_softc_t *sc, uhci_soft_qh_t *sqh)
{
	struct uhci_vframe *vf = &sc->sc_vframes[sqh->pos];
	uhci_soft_qh_t *pqh;

	DPRINTFN(4, ("uhci_remove_intr: n=%d sqh=%p\n", sqh->pos, sqh));

	/* See comment in uhci_remove_ctrl() */

	usb_syncmem(&sqh->dma, sqh->offs + offsetof(uhci_qh_t, qh_elink),
	    sizeof(sqh->qh.qh_elink),
	    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
	if (!(sqh->qh.qh_elink & htole32(UHCI_PTR_T))) {
		sqh->qh.qh_elink = htole32(UHCI_PTR_T);
		usb_syncmem(&sqh->dma,
		    sqh->offs + offsetof(uhci_qh_t, qh_elink),
		    sizeof(sqh->qh.qh_elink),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
		delay(UHCI_QH_REMOVE_DELAY);
	}

	pqh = uhci_find_prev_qh(vf->hqh, sqh);
	usb_syncmem(&sqh->dma, sqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(sqh->qh.qh_hlink),
	    BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
	pqh->hlink       = sqh->hlink;
	pqh->qh.qh_hlink = sqh->qh.qh_hlink;
	usb_syncmem(&pqh->dma, pqh->offs + offsetof(uhci_qh_t, qh_hlink),
	    sizeof(pqh->qh.qh_hlink),
	    BUS_DMASYNC_PREWRITE);
	delay(UHCI_QH_REMOVE_DELAY);
	if (vf->eqh == sqh)
		vf->eqh = pqh;
	vf->bandwidth--;
}

usbd_status
uhci_device_setintr(uhci_softc_t *sc, struct uhci_pipe *upipe, int ival)
{
	uhci_soft_qh_t *sqh;
	int i, npoll, s;
	u_int bestbw, bw, bestoffs, offs;

	DPRINTFN(2, ("uhci_device_setintr: pipe=%p\n", upipe));
	if (ival == 0) {
		printf("uhci_device_setintr: 0 interval\n");
		return (USBD_INVAL);
	}

	if (ival > UHCI_VFRAMELIST_COUNT)
		ival = UHCI_VFRAMELIST_COUNT;
	npoll = (UHCI_VFRAMELIST_COUNT + ival - 1) / ival;
	DPRINTFN(2, ("uhci_device_setintr: ival=%d npoll=%d\n", ival, npoll));

	upipe->u.intr.npoll = npoll;
	upipe->u.intr.qhs =
		malloc(npoll * sizeof(uhci_soft_qh_t *), M_USBHC, M_WAITOK);

	/*
	 * Figure out which offset in the schedule that has most
	 * bandwidth left over.
	 */
#define MOD(i) ((i) & (UHCI_VFRAMELIST_COUNT-1))
	for (bestoffs = offs = 0, bestbw = ~0; offs < ival; offs++) {
		for (bw = i = 0; i < npoll; i++)
			bw += sc->sc_vframes[MOD(i * ival + offs)].bandwidth;
		if (bw < bestbw) {
			bestbw = bw;
			bestoffs = offs;
		}
	}
	DPRINTFN(1, ("uhci_device_setintr: bw=%d offs=%d\n", bestbw, bestoffs));

	for(i = 0; i < npoll; i++) {
		upipe->u.intr.qhs[i] = sqh = uhci_alloc_sqh(sc);
		sqh->elink = NULL;
		sqh->qh.qh_elink = htole32(UHCI_PTR_T);
		usb_syncmem(&sqh->dma,
		    sqh->offs + offsetof(uhci_qh_t, qh_elink),
		    sizeof(sqh->qh.qh_elink),
		    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
		sqh->pos = MOD(i * ival + bestoffs);
	}
#undef MOD

	s = splusb();
	/* Enter QHs into the controller data structures. */
	for(i = 0; i < npoll; i++)
		uhci_add_intr(sc, upipe->u.intr.qhs[i]);
	splx(s);

	DPRINTFN(5, ("uhci_device_setintr: returns %p\n", upipe));
	return (USBD_NORMAL_COMPLETION);
}

/* Open a new pipe. */
usbd_status
uhci_open(usbd_pipe_handle pipe)
{
	uhci_softc_t *sc = pipe->device->bus->hci_private;
	struct uhci_pipe *upipe = (struct uhci_pipe *)pipe;
	usb_endpoint_descriptor_t *ed = pipe->endpoint->edesc;
	usbd_status err;
	int ival;

	DPRINTFN(1, ("uhci_open: pipe=%p, addr=%d, endpt=%d (%d)\n",
		     pipe, pipe->device->address,
		     ed->bEndpointAddress, sc->sc_addr));

	upipe->aborting = 0;
	upipe->nexttoggle = 0;

	if (pipe->device->address == sc->sc_addr) {
		switch (ed->bEndpointAddress) {
		case USB_CONTROL_ENDPOINT:
			pipe->methods = &uhci_root_ctrl_methods;
			break;
		case UE_DIR_IN | UHCI_INTR_ENDPT:
			pipe->methods = &uhci_root_intr_methods;
			break;
		default:
			return (USBD_INVAL);
		}
	} else {
		switch (ed->bmAttributes & UE_XFERTYPE) {
		case UE_CONTROL:
			pipe->methods = &uhci_device_ctrl_methods;
			upipe->u.ctl.sqh = uhci_alloc_sqh(sc);
			if (upipe->u.ctl.sqh == NULL)
				goto bad;
			upipe->u.ctl.setup = uhci_alloc_std(sc);
			if (upipe->u.ctl.setup == NULL) {
				uhci_free_sqh(sc, upipe->u.ctl.sqh);
				goto bad;
			}
			upipe->u.ctl.stat = uhci_alloc_std(sc);
			if (upipe->u.ctl.stat == NULL) {
				uhci_free_sqh(sc, upipe->u.ctl.sqh);
				uhci_free_std(sc, upipe->u.ctl.setup);
				goto bad;
			}
			err = usb_allocmem(&sc->sc_bus,
				  sizeof(usb_device_request_t),
				  0, &upipe->u.ctl.reqdma);
			if (err) {
				uhci_free_sqh(sc, upipe->u.ctl.sqh);
				uhci_free_std(sc, upipe->u.ctl.setup);
				uhci_free_std(sc, upipe->u.ctl.stat);
				goto bad;
			}
			break;
		case UE_INTERRUPT:
			pipe->methods = &uhci_device_intr_methods;
			ival = pipe->interval;
			if (ival == USBD_DEFAULT_INTERVAL)
				ival = ed->bInterval;
			return (uhci_device_setintr(sc, upipe, ival));
		case UE_ISOCHRONOUS:
			pipe->methods = &uhci_device_isoc_methods;
			return (uhci_setup_isoc(pipe));
		case UE_BULK:
			pipe->methods = &uhci_device_bulk_methods;
			upipe->u.bulk.sqh = uhci_alloc_sqh(sc);
			if (upipe->u.bulk.sqh == NULL)
				goto bad;
			break;
		}
	}
	return (USBD_NORMAL_COMPLETION);

 bad:
	return (USBD_NOMEM);
}

/*
 * Data structures and routines to emulate the root hub.
 */
usb_device_descriptor_t uhci_devd = {
	USB_DEVICE_DESCRIPTOR_SIZE,
	UDESC_DEVICE,		/* type */
	{0x00, 0x01},		/* USB version */
	UDCLASS_HUB,		/* class */
	UDSUBCLASS_HUB,		/* subclass */
	UDPROTO_FSHUB,		/* protocol */
	64,			/* max packet */
	{0},{0},{0x00,0x01},	/* device id */
	1,2,0,			/* string indicies */
	1			/* # of configurations */
};

const usb_config_descriptor_t uhci_confd = {
	USB_CONFIG_DESCRIPTOR_SIZE,
	UDESC_CONFIG,
	{USB_CONFIG_DESCRIPTOR_SIZE +
	 USB_INTERFACE_DESCRIPTOR_SIZE +
	 USB_ENDPOINT_DESCRIPTOR_SIZE},
	1,
	1,
	0,
	UC_ATTR_MBO | UC_SELF_POWERED,
	0			/* max power */
};

const usb_interface_descriptor_t uhci_ifcd = {
	USB_INTERFACE_DESCRIPTOR_SIZE,
	UDESC_INTERFACE,
	0,
	0,
	1,
	UICLASS_HUB,
	UISUBCLASS_HUB,
	UIPROTO_FSHUB,
	0
};

const usb_endpoint_descriptor_t uhci_endpd = {
	USB_ENDPOINT_DESCRIPTOR_SIZE,
	UDESC_ENDPOINT,
	UE_DIR_IN | UHCI_INTR_ENDPT,
	UE_INTERRUPT,
	{8},
	255
};

const usb_hub_descriptor_t uhci_hubd_piix = {
	USB_HUB_DESCRIPTOR_SIZE,
	UDESC_HUB,
	2,
	{ UHD_PWR_NO_SWITCH | UHD_OC_INDIVIDUAL, 0 },
	50,			/* power on to power good */
	0,
	{ 0x00 },		/* both ports are removable */
	{ 0 },
};

/*
 * The USB hub protocol requires that SET_FEATURE(PORT_RESET) also
 * enables the port, and also states that SET_FEATURE(PORT_ENABLE)
 * should not be used by the USB subsystem.  As we cannot issue a
 * SET_FEATURE(PORT_ENABLE) externally, we must ensure that the port
 * will be enabled as part of the reset.
 *
 * On the VT83C572, the port cannot be successfully enabled until the
 * outstanding "port enable change" and "connection status change"
 * events have been reset.
 */
Static usbd_status
uhci_portreset(uhci_softc_t *sc, int index)
{
	int lim, port, x;

	if (index == 1)
		port = UHCI_PORTSC1;
	else if (index == 2)
		port = UHCI_PORTSC2;
	else
		return (USBD_IOERROR);

	x = URWMASK(UREAD2(sc, port));
	UWRITE2(sc, port, x | UHCI_PORTSC_PR);

	usb_delay_ms(&sc->sc_bus, USB_PORT_ROOT_RESET_DELAY);

	DPRINTFN(3,("uhci port %d reset, status0 = 0x%04x\n",
		    index, UREAD2(sc, port)));

	x = URWMASK(UREAD2(sc, port));
	UWRITE2(sc, port, x & ~(UHCI_PORTSC_PR | UHCI_PORTSC_SUSP));

	delay(100);

	DPRINTFN(3,("uhci port %d reset, status1 = 0x%04x\n",
		    index, UREAD2(sc, port)));

	x = URWMASK(UREAD2(sc, port));
	UWRITE2(sc, port, x  | UHCI_PORTSC_PE);

	for (lim = 10; --lim > 0;) {
		usb_delay_ms(&sc->sc_bus, USB_PORT_RESET_DELAY);

		x = UREAD2(sc, port);

		DPRINTFN(3,("uhci port %d iteration %u, status = 0x%04x\n",
			    index, lim, x));

		if (!(x & UHCI_PORTSC_CCS)) {
			/*
			 * No device is connected (or was disconnected
			 * during reset).  Consider the port reset.
			 * The delay must be long enough to ensure on
			 * the initial iteration that the device
			 * connection will have been registered.  50ms
			 * appears to be sufficient, but 20ms is not.
			 */
			DPRINTFN(3,("uhci port %d loop %u, device detached\n",
				    index, lim));
			break;
		}

		if (x & (UHCI_PORTSC_POEDC | UHCI_PORTSC_CSC)) {
			/*
			 * Port enabled changed and/or connection
			 * status changed were set.  Reset either or
			 * both raised flags (by writing a 1 to that
			 * bit), and wait again for state to settle.
			 */
			UWRITE2(sc, port, URWMASK(x) |
				(x & (UHCI_PORTSC_POEDC | UHCI_PORTSC_CSC)));
			continue;
		}

		if (x & UHCI_PORTSC_PE)
			/* Port is enabled */
			break;

		UWRITE2(sc, port, URWMASK(x) | UHCI_PORTSC_PE);
	}

	DPRINTFN(3,("uhci port %d reset, status2 = 0x%04x\n",
		    index, UREAD2(sc, port)));

	if (lim <= 0) {
		DPRINTFN(1,("uhci port %d reset timed out\n", index));
		return (USBD_TIMEOUT);
	}

	sc->sc_isreset = 1;
	return (USBD_NORMAL_COMPLETION);
}

/*
 * Simulate a hardware hub by handling all the necessary requests.
 */
usbd_status
uhci_root_ctrl_transfer(usbd_xfer_handle xfer)
{
	usbd_status err;

	/* Insert last in queue. */
	err = usb_insert_transfer(xfer);
	if (err)
		return (err);

	/*
	 * Pipe isn't running (otherwise err would be USBD_INPROG),
	 * so start it first.
	 */
	return (uhci_root_ctrl_start(SIMPLEQ_FIRST(&xfer->pipe->queue)));
}

usbd_status
uhci_root_ctrl_start(usbd_xfer_handle xfer)
{
	uhci_softc_t *sc = xfer->pipe->device->bus->hci_private;
	usb_device_request_t *req;
	void *buf = NULL;
	int port, x;
	int s, len, value, index, status, change, l, totlen = 0;
	usb_port_status_t ps;
	usbd_status err;

	if (sc->sc_dying)
		return (USBD_IOERROR);

#ifdef DIAGNOSTIC
	if (!(xfer->rqflags & URQ_REQUEST))
		panic("uhci_root_ctrl_transfer: not a request");
#endif
	req = &xfer->request;

	DPRINTFN(2,("uhci_root_ctrl_control type=0x%02x request=%02x\n",
		    req->bmRequestType, req->bRequest));

	len = UGETW(req->wLength);
	value = UGETW(req->wValue);
	index = UGETW(req->wIndex);

	if (len != 0)
		buf = KERNADDR(&xfer->dmabuf, 0);

#define C(x,y) ((x) | ((y) << 8))
	switch(C(req->bRequest, req->bmRequestType)) {
	case C(UR_CLEAR_FEATURE, UT_WRITE_DEVICE):
	case C(UR_CLEAR_FEATURE, UT_WRITE_INTERFACE):
	case C(UR_CLEAR_FEATURE, UT_WRITE_ENDPOINT):
		/*
		 * DEVICE_REMOTE_WAKEUP and ENDPOINT_HALT are no-ops
		 * for the integrated root hub.
		 */
		break;
	case C(UR_GET_CONFIG, UT_READ_DEVICE):
		if (len > 0) {
			*(u_int8_t *)buf = sc->sc_conf;
			totlen = 1;
		}
		break;
	case C(UR_GET_DESCRIPTOR, UT_READ_DEVICE):
		DPRINTFN(2,("uhci_root_ctrl_control wValue=0x%04x\n", value));
		if (len == 0)
			break;
		switch(value >> 8) {
		case UDESC_DEVICE:
			if ((value & 0xff) != 0) {
				err = USBD_IOERROR;
				goto ret;
			}
			totlen = l = min(len, USB_DEVICE_DESCRIPTOR_SIZE);
			USETW(uhci_devd.idVendor, sc->sc_id_vendor);
			memcpy(buf, &uhci_devd, l);
			break;
		case UDESC_CONFIG:
			if ((value & 0xff) != 0) {
				err = USBD_IOERROR;
				goto ret;
			}
			totlen = l = min(len, USB_CONFIG_DESCRIPTOR_SIZE);
			memcpy(buf, &uhci_confd, l);
			buf = (char *)buf + l;
			len -= l;
			l = min(len, USB_INTERFACE_DESCRIPTOR_SIZE);
			totlen += l;
			memcpy(buf, &uhci_ifcd, l);
			buf = (char *)buf + l;
			len -= l;
			l = min(len, USB_ENDPOINT_DESCRIPTOR_SIZE);
			totlen += l;
			memcpy(buf, &uhci_endpd, l);
			break;
		case UDESC_STRING:
#define sd ((usb_string_descriptor_t *)buf)
			switch (value & 0xff) {
			case 0: /* Language table */
				totlen = usb_makelangtbl(sd, len);
				break;
			case 1: /* Vendor */
				totlen = usb_makestrdesc(sd, len,
							 sc->sc_vendor);
				break;
			case 2: /* Product */
				totlen = usb_makestrdesc(sd, len,
							 "UHCI root hub");
				break;
			}
#undef sd
			break;
		default:
			err = USBD_IOERROR;
			goto ret;
		}
		break;
	case C(UR_GET_INTERFACE, UT_READ_INTERFACE):
		if (len > 0) {
			*(u_int8_t *)buf = 0;
			totlen = 1;
		}
		break;
	case C(UR_GET_STATUS, UT_READ_DEVICE):
		if (len > 1) {
			USETW(((usb_status_t *)buf)->wStatus,UDS_SELF_POWERED);
			totlen = 2;
		}
		break;
	case C(UR_GET_STATUS, UT_READ_INTERFACE):
	case C(UR_GET_STATUS, UT_READ_ENDPOINT):
		if (len > 1) {
			USETW(((usb_status_t *)buf)->wStatus, 0);
			totlen = 2;
		}
		break;
	case C(UR_SET_ADDRESS, UT_WRITE_DEVICE):
		if (value >= USB_MAX_DEVICES) {
			err = USBD_IOERROR;
			goto ret;
		}
		sc->sc_addr = value;
		break;
	case C(UR_SET_CONFIG, UT_WRITE_DEVICE):
		if (value != 0 && value != 1) {
			err = USBD_IOERROR;
			goto ret;
		}
		sc->sc_conf = value;
		break;
	case C(UR_SET_DESCRIPTOR, UT_WRITE_DEVICE):
		break;
	case C(UR_SET_FEATURE, UT_WRITE_DEVICE):
	case C(UR_SET_FEATURE, UT_WRITE_INTERFACE):
	case C(UR_SET_FEATURE, UT_WRITE_ENDPOINT):
		err = USBD_IOERROR;
		goto ret;
	case C(UR_SET_INTERFACE, UT_WRITE_INTERFACE):
		break;
	case C(UR_SYNCH_FRAME, UT_WRITE_ENDPOINT):
		break;
	/* Hub requests */
	case C(UR_CLEAR_FEATURE, UT_WRITE_CLASS_DEVICE):
		break;
	case C(UR_CLEAR_FEATURE, UT_WRITE_CLASS_OTHER):
		DPRINTFN(3, ("uhci_root_ctrl_control: UR_CLEAR_PORT_FEATURE "
			     "port=%d feature=%d\n",
			     index, value));
		if (index == 1)
			port = UHCI_PORTSC1;
		else if (index == 2)
			port = UHCI_PORTSC2;
		else {
			err = USBD_IOERROR;
			goto ret;
		}
		switch(value) {
		case UHF_PORT_ENABLE:
			x = URWMASK(UREAD2(sc, port));
			UWRITE2(sc, port, x & ~UHCI_PORTSC_PE);
			break;
		case UHF_PORT_SUSPEND:
			x = URWMASK(UREAD2(sc, port));
			if (!(x & UHCI_PORTSC_SUSP)) /* not suspended */
				break;
			UWRITE2(sc, port, x | UHCI_PORTSC_RD);
			/* see USB2 spec ch. 7.1.7.7 */
			usb_delay_ms(&sc->sc_bus, 20);
			UWRITE2(sc, port, x & ~UHCI_PORTSC_SUSP);
			/* 10ms resume delay must be provided by caller */
			break;
		case UHF_PORT_RESET:
			x = URWMASK(UREAD2(sc, port));
			UWRITE2(sc, port, x & ~UHCI_PORTSC_PR);
			break;
		case UHF_C_PORT_CONNECTION:
			x = URWMASK(UREAD2(sc, port));
			UWRITE2(sc, port, x | UHCI_PORTSC_CSC);
			break;
		case UHF_C_PORT_ENABLE:
			x = URWMASK(UREAD2(sc, port));
			UWRITE2(sc, port, x | UHCI_PORTSC_POEDC);
			break;
		case UHF_C_PORT_OVER_CURRENT:
			x = URWMASK(UREAD2(sc, port));
			UWRITE2(sc, port, x | UHCI_PORTSC_OCIC);
			break;
		case UHF_C_PORT_RESET:
			sc->sc_isreset = 0;
			err = USBD_NORMAL_COMPLETION;
			goto ret;
		case UHF_PORT_CONNECTION:
		case UHF_PORT_OVER_CURRENT:
		case UHF_PORT_POWER:
		case UHF_PORT_LOW_SPEED:
		case UHF_C_PORT_SUSPEND:
		default:
			err = USBD_IOERROR;
			goto ret;
		}
		break;
	case C(UR_GET_BUS_STATE, UT_READ_CLASS_OTHER):
		if (index == 1)
			port = UHCI_PORTSC1;
		else if (index == 2)
			port = UHCI_PORTSC2;
		else {
			err = USBD_IOERROR;
			goto ret;
		}
		if (len > 0) {
			*(u_int8_t *)buf =
				(UREAD2(sc, port) & UHCI_PORTSC_LS) >>
				UHCI_PORTSC_LS_SHIFT;
			totlen = 1;
		}
		break;
	case C(UR_GET_DESCRIPTOR, UT_READ_CLASS_DEVICE):
		if (len == 0)
			break;
		if ((value & 0xff) != 0) {
			err = USBD_IOERROR;
			goto ret;
		}
		l = min(len, USB_HUB_DESCRIPTOR_SIZE);
		totlen = l;
		memcpy(buf, &uhci_hubd_piix, l);
		break;
	case C(UR_GET_STATUS, UT_READ_CLASS_DEVICE):
		if (len != 4) {
			err = USBD_IOERROR;
			goto ret;
		}
		memset(buf, 0, len);
		totlen = len;
		break;
	case C(UR_GET_STATUS, UT_READ_CLASS_OTHER):
		if (index == 1)
			port = UHCI_PORTSC1;
		else if (index == 2)
			port = UHCI_PORTSC2;
		else {
			err = USBD_IOERROR;
			goto ret;
		}
		if (len != 4) {
			err = USBD_IOERROR;
			goto ret;
		}
		x = UREAD2(sc, port);
		status = change = 0;
		if (x & UHCI_PORTSC_CCS)
			status |= UPS_CURRENT_CONNECT_STATUS;
		if (x & UHCI_PORTSC_CSC)
			change |= UPS_C_CONNECT_STATUS;
		if (x & UHCI_PORTSC_PE)
			status |= UPS_PORT_ENABLED;
		if (x & UHCI_PORTSC_POEDC)
			change |= UPS_C_PORT_ENABLED;
		if (x & UHCI_PORTSC_OCI)
			status |= UPS_OVERCURRENT_INDICATOR;
		if (x & UHCI_PORTSC_OCIC)
			change |= UPS_C_OVERCURRENT_INDICATOR;
		if (x & UHCI_PORTSC_SUSP)
			status |= UPS_SUSPEND;
		if (x & UHCI_PORTSC_LSDA)
			status |= UPS_LOW_SPEED;
		status |= UPS_PORT_POWER;
		if (sc->sc_isreset)
			change |= UPS_C_PORT_RESET;
		USETW(ps.wPortStatus, status);
		USETW(ps.wPortChange, change);
		l = min(len, sizeof ps);
		memcpy(buf, &ps, l);
		totlen = l;
		break;
	case C(UR_SET_DESCRIPTOR, UT_WRITE_CLASS_DEVICE):
		err = USBD_IOERROR;
		goto ret;
	case C(UR_SET_FEATURE, UT_WRITE_CLASS_DEVICE):
		break;
	case C(UR_SET_FEATURE, UT_WRITE_CLASS_OTHER):
		if (index == 1)
			port = UHCI_PORTSC1;
		else if (index == 2)
			port = UHCI_PORTSC2;
		else {
			err = USBD_IOERROR;
			goto ret;
		}
		switch(value) {
		case UHF_PORT_ENABLE:
			x = URWMASK(UREAD2(sc, port));
			UWRITE2(sc, port, x | UHCI_PORTSC_PE);
			break;
		case UHF_PORT_SUSPEND:
			x = URWMASK(UREAD2(sc, port));
			UWRITE2(sc, port, x | UHCI_PORTSC_SUSP);
			break;
		case UHF_PORT_RESET:
			err = uhci_portreset(sc, index);
			goto ret;
		case UHF_PORT_POWER:
			/* Pretend we turned on power */
			err = USBD_NORMAL_COMPLETION;
			goto ret;
		case UHF_C_PORT_CONNECTION:
		case UHF_C_PORT_ENABLE:
		case UHF_C_PORT_OVER_CURRENT:
		case UHF_PORT_CONNECTION:
		case UHF_PORT_OVER_CURRENT:
		case UHF_PORT_LOW_SPEED:
		case UHF_C_PORT_SUSPEND:
		case UHF_C_PORT_RESET:
		default:
			err = USBD_IOERROR;
			goto ret;
		}
		break;
	default:
		err = USBD_IOERROR;
		goto ret;
	}
	xfer->actlen = totlen;
	err = USBD_NORMAL_COMPLETION;
 ret:
	xfer->status = err;
	s = splusb();
	usb_transfer_complete(xfer);
	splx(s);
	return (USBD_IN_PROGRESS);
}

/* Abort a root control request. */
void
uhci_root_ctrl_abort(usbd_xfer_handle xfer)
{
	/* Nothing to do, all transfers are synchronous. */
}

/* Close the root pipe. */
void
uhci_root_ctrl_close(usbd_pipe_handle pipe)
{
	DPRINTF(("uhci_root_ctrl_close\n"));
}

/* Abort a root interrupt request. */
void
uhci_root_intr_abort(usbd_xfer_handle xfer)
{
	uhci_softc_t *sc = xfer->pipe->device->bus->hci_private;

	usb_uncallout(sc->sc_poll_handle, uhci_poll_hub, xfer);
	sc->sc_intr_xfer = NULL;

	if (xfer->pipe->intrxfer == xfer) {
		DPRINTF(("uhci_root_intr_abort: remove\n"));
		xfer->pipe->intrxfer = 0;
	}
	xfer->status = USBD_CANCELLED;
#ifdef DIAGNOSTIC
	UXFER(xfer)->iinfo.isdone = 1;
#endif
	usb_transfer_complete(xfer);
}

usbd_status
uhci_root_intr_transfer(usbd_xfer_handle xfer)
{
	usbd_status err;

	/* Insert last in queue. */
	err = usb_insert_transfer(xfer);
	if (err)
		return (err);

	/*
	 * Pipe isn't running (otherwise err would be USBD_INPROG),
	 * start first
	 */
	return (uhci_root_intr_start(SIMPLEQ_FIRST(&xfer->pipe->queue)));
}

/* Start a transfer on the root interrupt pipe */
usbd_status
uhci_root_intr_start(usbd_xfer_handle xfer)
{
	usbd_pipe_handle pipe = xfer->pipe;
	uhci_softc_t *sc = pipe->device->bus->hci_private;
	unsigned int ival;

	DPRINTFN(3, ("uhci_root_intr_start: xfer=%p len=%d flags=%d\n",
		     xfer, xfer->length, xfer->flags));

	if (sc->sc_dying)
		return (USBD_IOERROR);

	/* XXX temporary variable needed to avoid gcc3 warning */
	ival = xfer->pipe->endpoint->edesc->bInterval;
	sc->sc_ival = mstohz(ival);
	usb_callout(sc->sc_poll_handle, sc->sc_ival, uhci_poll_hub, xfer);
	sc->sc_intr_xfer = xfer;
	return (USBD_IN_PROGRESS);
}

/* Close the root interrupt pipe. */
void
uhci_root_intr_close(usbd_pipe_handle pipe)
{
	uhci_softc_t *sc = pipe->device->bus->hci_private;

	usb_uncallout(sc->sc_poll_handle, uhci_poll_hub, sc->sc_intr_xfer);
	sc->sc_intr_xfer = NULL;
	DPRINTF(("uhci_root_intr_close\n"));
}