source: rtems-libbsd/freebsd/sys/dev/usb/usb_dev.c @ 3d1e767

#include <machine/rtems-bsd-kernel-space.h>

/* $FreeBSD$ */
/*-
 * Copyright (c) 2006-2008 Hans Petter Selasky. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *
 * usb_dev.c - An abstraction layer for creating devices under /dev/...
 */

#ifdef USB_GLOBAL_INCLUDE_FILE
#include USB_GLOBAL_INCLUDE_FILE
#else
#include <sys/stdint.h>
#include <sys/stddef.h>
#include <rtems/bsd/sys/param.h>
#include <sys/queue.h>
#include <sys/types.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/bus.h>
#include <sys/module.h>
#include <rtems/bsd/sys/lock.h>
#include <sys/mutex.h>
#include <sys/condvar.h>
#include <sys/sysctl.h>
#include <sys/sx.h>
#include <rtems/bsd/sys/unistd.h>
#include <sys/callout.h>
#include <sys/malloc.h>
#include <sys/priv.h>
#include <sys/vnode.h>
#include <sys/conf.h>
#include <sys/fcntl.h>

#include <dev/usb/usb.h>
#include <dev/usb/usb_ioctl.h>
#include <dev/usb/usbdi.h>
#include <dev/usb/usbdi_util.h>

#define USB_DEBUG_VAR usb_fifo_debug

#include <dev/usb/usb_core.h>
#include <dev/usb/usb_dev.h>
#include <dev/usb/usb_mbuf.h>
#include <dev/usb/usb_process.h>
#include <dev/usb/usb_device.h>
#include <dev/usb/usb_debug.h>
#include <dev/usb/usb_busdma.h>
#include <dev/usb/usb_generic.h>
#include <dev/usb/usb_dynamic.h>
#include <dev/usb/usb_util.h>

#include <dev/usb/usb_controller.h>
#include <dev/usb/usb_bus.h>

#include <sys/filio.h>
#include <sys/ttycom.h>
#include <sys/syscallsubr.h>

#include <machine/stdarg.h>
#endif                  /* USB_GLOBAL_INCLUDE_FILE */

#if USB_HAVE_UGEN

#ifdef USB_DEBUG
static int usb_fifo_debug = 0;

static SYSCTL_NODE(_hw_usb, OID_AUTO, dev, CTLFLAG_RW, 0, "USB device");
SYSCTL_INT(_hw_usb_dev, OID_AUTO, debug, CTLFLAG_RWTUN,
    &usb_fifo_debug, 0, "Debug Level");
#endif

#if ((__FreeBSD_version >= 700001) || (__FreeBSD_version == 0) || \
     ((__FreeBSD_version >= 600034) && (__FreeBSD_version < 700000)))
#define USB_UCRED struct ucred *ucred,
#else
#define USB_UCRED
#endif

/* prototypes */

static int      usb_fifo_open(struct usb_cdev_privdata *, 
                    struct usb_fifo *, int);
static void     usb_fifo_close(struct usb_fifo *, int);
static void     usb_dev_init(void *);
static void     usb_dev_init_post(void *);
static void     usb_dev_uninit(void *);
static int      usb_fifo_uiomove(struct usb_fifo *, void *, int,
                    struct uio *);
static void     usb_fifo_check_methods(struct usb_fifo_methods *);
static struct   usb_fifo *usb_fifo_alloc(struct mtx *);
static struct   usb_endpoint *usb_dev_get_ep(struct usb_device *, uint8_t,
                    uint8_t);
static void     usb_loc_fill(struct usb_fs_privdata *,
                    struct usb_cdev_privdata *);
static void     usb_close(void *);
static usb_error_t usb_ref_device(struct usb_cdev_privdata *, struct usb_cdev_refdata *, int);
static usb_error_t usb_usb_ref_device(struct usb_cdev_privdata *, struct usb_cdev_refdata *);
static void     usb_unref_device(struct usb_cdev_privdata *, struct usb_cdev_refdata *);

static d_open_t usb_open;
static d_ioctl_t usb_ioctl;
static d_read_t usb_read;
static d_write_t usb_write;
static d_poll_t usb_poll;
static d_kqfilter_t usb_kqfilter;

static d_ioctl_t usb_static_ioctl;

static usb_fifo_open_t usb_fifo_dummy_open;
static usb_fifo_close_t usb_fifo_dummy_close;
static usb_fifo_ioctl_t usb_fifo_dummy_ioctl;
static usb_fifo_cmd_t usb_fifo_dummy_cmd;

/* character device structure used for devices (/dev/ugenX.Y and /dev/uXXX) */
struct cdevsw usb_devsw = {
        .d_version = D_VERSION,
        .d_open = usb_open,
        .d_ioctl = usb_ioctl,
        .d_name = "usbdev",
        .d_flags = D_TRACKCLOSE,
        .d_read = usb_read,
        .d_write = usb_write,
        .d_poll = usb_poll,
        .d_kqfilter = usb_kqfilter,
};

static struct cdev* usb_dev = NULL;

/* character device structure used for /dev/usb */
static struct cdevsw usb_static_devsw = {
        .d_version = D_VERSION,
        .d_ioctl = usb_static_ioctl,
        .d_name = "usb"
};

static TAILQ_HEAD(, usb_symlink) usb_sym_head;
static struct sx usb_sym_lock;

struct mtx usb_ref_lock;

/*------------------------------------------------------------------------*
 *      usb_loc_fill
 *
 * This is used to fill out a usb_cdev_privdata structure based on the
 * device's address as contained in usb_fs_privdata.
 *------------------------------------------------------------------------*/
static void
usb_loc_fill(struct usb_fs_privdata* pd, struct usb_cdev_privdata *cpd)
{
        cpd->bus_index = pd->bus_index;
        cpd->dev_index = pd->dev_index;
        cpd->ep_addr = pd->ep_addr;
        cpd->fifo_index = pd->fifo_index;
}

/*------------------------------------------------------------------------*
 *      usb_ref_device
 *
 * This function is used to atomically refer an USB device by its
 * device location. If this function returns success the USB device
 * will not dissappear until the USB device is unreferenced.
 *
 * Return values:
 *  0: Success, refcount incremented on the given USB device.
 *  Else: Failure.
 *------------------------------------------------------------------------*/
static usb_error_t
usb_ref_device(struct usb_cdev_privdata *cpd, 
    struct usb_cdev_refdata *crd, int need_uref)
{
        struct usb_fifo **ppf;
        struct usb_fifo *f;

        DPRINTFN(2, "cpd=%p need uref=%d\n", cpd, need_uref);

        /* clear all refs */
        memset(crd, 0, sizeof(*crd));

        mtx_lock(&usb_ref_lock);
        cpd->bus = devclass_get_softc(usb_devclass_ptr, cpd->bus_index);
        if (cpd->bus == NULL) {
                DPRINTFN(2, "no bus at %u\n", cpd->bus_index);
                goto error;
        }
        cpd->udev = cpd->bus->devices[cpd->dev_index];
        if (cpd->udev == NULL) {
                DPRINTFN(2, "no device at %u\n", cpd->dev_index);
                goto error;
        }
        if (cpd->udev->state == USB_STATE_DETACHED &&
            (need_uref != 2)) {
                DPRINTFN(2, "device is detached\n");
                goto error;
        }
        if (need_uref) {
                DPRINTFN(2, "ref udev - needed\n");

                if (cpd->udev->refcount == USB_DEV_REF_MAX) {
                        DPRINTFN(2, "no dev ref\n");
                        goto error;
                }
                cpd->udev->refcount++;

                mtx_unlock(&usb_ref_lock);

                /*
                 * We need to grab the enumeration SX-lock before
                 * grabbing the FIFO refs to avoid deadlock at detach!
                 */
                crd->do_unlock = usbd_enum_lock(cpd->udev);

                mtx_lock(&usb_ref_lock);

                /* 
                 * Set "is_uref" after grabbing the default SX lock
                 */
                crd->is_uref = 1;
        }

        /* check if we are doing an open */
        if (cpd->fflags == 0) {
                /* use zero defaults */
        } else {
                /* check for write */
                if (cpd->fflags & FWRITE) {
                        ppf = cpd->udev->fifo;
                        f = ppf[cpd->fifo_index + USB_FIFO_TX];
                        crd->txfifo = f;
                        crd->is_write = 1;      /* ref */
                        if (f == NULL || f->refcount == USB_FIFO_REF_MAX)
                                goto error;
                        if (f->curr_cpd != cpd)
                                goto error;
                        /* check if USB-FS is active */
                        if (f->fs_ep_max != 0) {
                                crd->is_usbfs = 1;
                        }
                }

                /* check for read */
                if (cpd->fflags & FREAD) {
                        ppf = cpd->udev->fifo;
                        f = ppf[cpd->fifo_index + USB_FIFO_RX];
                        crd->rxfifo = f;
                        crd->is_read = 1;       /* ref */
                        if (f == NULL || f->refcount == USB_FIFO_REF_MAX)
                                goto error;
                        if (f->curr_cpd != cpd)
                                goto error;
                        /* check if USB-FS is active */
                        if (f->fs_ep_max != 0) {
                                crd->is_usbfs = 1;
                        }
                }
        }

        /* when everything is OK we increment the refcounts */
        if (crd->is_write) {
                DPRINTFN(2, "ref write\n");
                crd->txfifo->refcount++;
        }
        if (crd->is_read) {
                DPRINTFN(2, "ref read\n");
                crd->rxfifo->refcount++;
        }
        mtx_unlock(&usb_ref_lock);

        return (0);

error:
        if (crd->do_unlock)
                usbd_enum_unlock(cpd->udev);

        if (crd->is_uref) {
                if (--(cpd->udev->refcount) == 0)
                        cv_broadcast(&cpd->udev->ref_cv);
        }
        mtx_unlock(&usb_ref_lock);
        DPRINTFN(2, "fail\n");

        /* clear all refs */
        memset(crd, 0, sizeof(*crd));

        return (USB_ERR_INVAL);
}

/*------------------------------------------------------------------------*
 *      usb_usb_ref_device
 *
 * This function is used to upgrade an USB reference to include the
 * USB device reference on a USB location.
 *
 * Return values:
 *  0: Success, refcount incremented on the given USB device.
 *  Else: Failure.
 *------------------------------------------------------------------------*/
static usb_error_t
usb_usb_ref_device(struct usb_cdev_privdata *cpd,
    struct usb_cdev_refdata *crd)
{
        /*
         * Check if we already got an USB reference on this location:
         */
        if (crd->is_uref)
                return (0);             /* success */

        /*
         * To avoid deadlock at detach we need to drop the FIFO ref
         * and re-acquire a new ref!
         */
        usb_unref_device(cpd, crd);

        return (usb_ref_device(cpd, crd, 1 /* need uref */));
}

/*------------------------------------------------------------------------*
 *      usb_unref_device
 *
 * This function will release the reference count by one unit for the
 * given USB device.
 *------------------------------------------------------------------------*/
static void
usb_unref_device(struct usb_cdev_privdata *cpd,
    struct usb_cdev_refdata *crd)
{

        DPRINTFN(2, "cpd=%p is_uref=%d\n", cpd, crd->is_uref);

        if (crd->do_unlock)
                usbd_enum_unlock(cpd->udev);

        mtx_lock(&usb_ref_lock);
        if (crd->is_read) {
                if (--(crd->rxfifo->refcount) == 0) {
                        cv_signal(&crd->rxfifo->cv_drain);
                }
                crd->is_read = 0;
        }
        if (crd->is_write) {
                if (--(crd->txfifo->refcount) == 0) {
                        cv_signal(&crd->txfifo->cv_drain);
                }
                crd->is_write = 0;
        }
        if (crd->is_uref) {
                crd->is_uref = 0;
                if (--(cpd->udev->refcount) == 0)
                        cv_broadcast(&cpd->udev->ref_cv);
        }
        mtx_unlock(&usb_ref_lock);
}

static struct usb_fifo *
usb_fifo_alloc(struct mtx *mtx)
{
        struct usb_fifo *f;

        f = malloc(sizeof(*f), M_USBDEV, M_WAITOK | M_ZERO);
        if (f != NULL) {
                cv_init(&f->cv_io, "FIFO-IO");
                cv_init(&f->cv_drain, "FIFO-DRAIN");
                f->priv_mtx = mtx;
                f->refcount = 1;
                knlist_init_mtx(&f->selinfo.si_note, mtx);
        }
        return (f);
}

/*------------------------------------------------------------------------*
 *      usb_fifo_create
 *------------------------------------------------------------------------*/
static int
usb_fifo_create(struct usb_cdev_privdata *cpd,
    struct usb_cdev_refdata *crd)
{
        struct usb_device *udev = cpd->udev;
        struct usb_fifo *f;
        struct usb_endpoint *ep;
        uint8_t n;
        uint8_t is_tx;
        uint8_t is_rx;
        uint8_t no_null;
        uint8_t is_busy;
        int e = cpd->ep_addr;

        is_tx = (cpd->fflags & FWRITE) ? 1 : 0;
        is_rx = (cpd->fflags & FREAD) ? 1 : 0;
        no_null = 1;
        is_busy = 0;

        /* Preallocated FIFO */
        if (e < 0) {
                DPRINTFN(5, "Preallocated FIFO\n");
                if (is_tx) {
                        f = udev->fifo[cpd->fifo_index + USB_FIFO_TX];
                        if (f == NULL)
                                return (EINVAL);
                        crd->txfifo = f;
                }
                if (is_rx) {
                        f = udev->fifo[cpd->fifo_index + USB_FIFO_RX];
                        if (f == NULL)
                                return (EINVAL);
                        crd->rxfifo = f;
                }
                return (0);
        }

        KASSERT(e >= 0 && e <= 15, ("endpoint %d out of range", e));

        /* search for a free FIFO slot */
        DPRINTFN(5, "Endpoint device, searching for 0x%02x\n", e);
        for (n = 0;; n += 2) {

                if (n == USB_FIFO_MAX) {
                        if (no_null) {
                                no_null = 0;
                                n = 0;
                        } else {
                                /* end of FIFOs reached */
                                DPRINTFN(5, "out of FIFOs\n");
                                return (ENOMEM);
                        }
                }
                /* Check for TX FIFO */
                if (is_tx) {
                        f = udev->fifo[n + USB_FIFO_TX];
                        if (f != NULL) {
                                if (f->dev_ep_index != e) {
                                        /* wrong endpoint index */
                                        continue;
                                }
                                if (f->curr_cpd != NULL) {
                                        /* FIFO is opened */
                                        is_busy = 1;
                                        continue;
                                }
                        } else if (no_null) {
                                continue;
                        }
                }
                /* Check for RX FIFO */
                if (is_rx) {
                        f = udev->fifo[n + USB_FIFO_RX];
                        if (f != NULL) {
                                if (f->dev_ep_index != e) {
                                        /* wrong endpoint index */
                                        continue;
                                }
                                if (f->curr_cpd != NULL) {
                                        /* FIFO is opened */
                                        is_busy = 1;
                                        continue;
                                }
                        } else if (no_null) {
                                continue;
                        }
                }
                break;
        }

        if (no_null == 0) {
                if (e >= (USB_EP_MAX / 2)) {
                        /* we don't create any endpoints in this range */
                        DPRINTFN(5, "ep out of range\n");
                        return (is_busy ? EBUSY : EINVAL);
                }
        }

        if ((e != 0) && is_busy) {
                /*
                 * Only the default control endpoint is allowed to be
                 * opened multiple times!
                 */
                DPRINTFN(5, "busy\n");
                return (EBUSY);
        }

        /* Check TX FIFO */
        if (is_tx &&
            (udev->fifo[n + USB_FIFO_TX] == NULL)) {
                ep = usb_dev_get_ep(udev, e, USB_FIFO_TX);
                DPRINTFN(5, "dev_get_endpoint(%d, 0x%x)\n", e, USB_FIFO_TX);
                if (ep == NULL) {
                        DPRINTFN(5, "dev_get_endpoint returned NULL\n");
                        return (EINVAL);
                }
                f = usb_fifo_alloc(&udev->device_mtx);
                if (f == NULL) {
                        DPRINTFN(5, "could not alloc tx fifo\n");
                        return (ENOMEM);
                }
                /* update some fields */
                f->fifo_index = n + USB_FIFO_TX;
                f->dev_ep_index = e;
                f->priv_sc0 = ep;
                f->methods = &usb_ugen_methods;
                f->iface_index = ep->iface_index;
                f->udev = udev;
                mtx_lock(&usb_ref_lock);
                udev->fifo[n + USB_FIFO_TX] = f;
                mtx_unlock(&usb_ref_lock);
        }
        /* Check RX FIFO */
        if (is_rx &&
            (udev->fifo[n + USB_FIFO_RX] == NULL)) {

                ep = usb_dev_get_ep(udev, e, USB_FIFO_RX);
                DPRINTFN(5, "dev_get_endpoint(%d, 0x%x)\n", e, USB_FIFO_RX);
                if (ep == NULL) {
                        DPRINTFN(5, "dev_get_endpoint returned NULL\n");
                        return (EINVAL);
                }
                f = usb_fifo_alloc(&udev->device_mtx);
                if (f == NULL) {
                        DPRINTFN(5, "could not alloc rx fifo\n");
                        return (ENOMEM);
                }
                /* update some fields */
                f->fifo_index = n + USB_FIFO_RX;
                f->dev_ep_index = e;
                f->priv_sc0 = ep;
                f->methods = &usb_ugen_methods;
                f->iface_index = ep->iface_index;
                f->udev = udev;
                mtx_lock(&usb_ref_lock);
                udev->fifo[n + USB_FIFO_RX] = f;
                mtx_unlock(&usb_ref_lock);
        }
        if (is_tx) {
                crd->txfifo = udev->fifo[n + USB_FIFO_TX];
        }
        if (is_rx) {
                crd->rxfifo = udev->fifo[n + USB_FIFO_RX];
        }
        /* fill out fifo index */
        DPRINTFN(5, "fifo index = %d\n", n);
        cpd->fifo_index = n;

        /* complete */

        return (0);
}

void
usb_fifo_free(struct usb_fifo *f)
{
        uint8_t n;

        if (f == NULL) {
                /* be NULL safe */
                return;
        }
        /* destroy symlink devices, if any */
        for (n = 0; n != 2; n++) {
                if (f->symlink[n]) {
                        usb_free_symlink(f->symlink[n]);
                        f->symlink[n] = NULL;
                }
        }
        mtx_lock(&usb_ref_lock);

        /* delink ourselves to stop calls from userland */
        if ((f->fifo_index < USB_FIFO_MAX) &&
            (f->udev != NULL) &&
            (f->udev->fifo[f->fifo_index] == f)) {
                f->udev->fifo[f->fifo_index] = NULL;
        } else {
                DPRINTFN(0, "USB FIFO %p has not been linked\n", f);
        }

        /* decrease refcount */
        f->refcount--;
        /* need to wait until all callers have exited */
        while (f->refcount != 0) {
                mtx_unlock(&usb_ref_lock);      /* avoid LOR */
                mtx_lock(f->priv_mtx);
                /* prevent write flush, if any */
                f->flag_iserror = 1;
                /* get I/O thread out of any sleep state */
                if (f->flag_sleeping) {
                        f->flag_sleeping = 0;
                        cv_broadcast(&f->cv_io);
                }
                mtx_unlock(f->priv_mtx);
                mtx_lock(&usb_ref_lock);

                /*
                 * Check if the "f->refcount" variable reached zero
                 * during the unlocked time before entering wait:
                 */
                if (f->refcount == 0)
                        break;

                /* wait for sync */
                cv_wait(&f->cv_drain, &usb_ref_lock);
        }
        mtx_unlock(&usb_ref_lock);

        /* take care of closing the device here, if any */
        usb_fifo_close(f, 0);

        cv_destroy(&f->cv_io);
        cv_destroy(&f->cv_drain);

        knlist_clear(&f->selinfo.si_note, 0);
        seldrain(&f->selinfo);
        knlist_destroy(&f->selinfo.si_note);

        free(f, M_USBDEV);
}

static struct usb_endpoint *
usb_dev_get_ep(struct usb_device *udev, uint8_t ep_index, uint8_t dir)
{
        struct usb_endpoint *ep;
        uint8_t ep_dir;

        if (ep_index == 0) {
                ep = &udev->ctrl_ep;
        } else {
                if (dir == USB_FIFO_RX) {
                        if (udev->flags.usb_mode == USB_MODE_HOST) {
                                ep_dir = UE_DIR_IN;
                        } else {
                                ep_dir = UE_DIR_OUT;
                        }
                } else {
                        if (udev->flags.usb_mode == USB_MODE_HOST) {
                                ep_dir = UE_DIR_OUT;
                        } else {
                                ep_dir = UE_DIR_IN;
                        }
                }
                ep = usbd_get_ep_by_addr(udev, ep_index | ep_dir);
        }

        if (ep == NULL) {
                /* if the endpoint does not exist then return */
                return (NULL);
        }
        if (ep->edesc == NULL) {
                /* invalid endpoint */
                return (NULL);
        }
        return (ep);                    /* success */
}

/*------------------------------------------------------------------------*
 *      usb_fifo_open
 *
 * Returns:
 * 0: Success
 * Else: Failure
 *------------------------------------------------------------------------*/
static int
usb_fifo_open(struct usb_cdev_privdata *cpd, 
    struct usb_fifo *f, int fflags)
{
        int err;

        if (f == NULL) {
                /* no FIFO there */
                DPRINTFN(2, "no FIFO\n");
                return (ENXIO);
        }
        /* remove FWRITE and FREAD flags */
        fflags &= ~(FWRITE | FREAD);

        /* set correct file flags */
        if ((f->fifo_index & 1) == USB_FIFO_TX) {
                fflags |= FWRITE;
        } else {
                fflags |= FREAD;
        }

        /* check if we are already opened */
        /* we don't need any locks when checking this variable */
        if (f->curr_cpd != NULL) {
                err = EBUSY;
                goto done;
        }

        /* reset short flag before open */
        f->flag_short = 0;

        /* call open method */
        err = (f->methods->f_open) (f, fflags);
        if (err) {
                goto done;
        }
        mtx_lock(f->priv_mtx);

        /* reset sleep flag */
        f->flag_sleeping = 0;

        /* reset error flag */
        f->flag_iserror = 0;

        /* reset complete flag */
        f->flag_iscomplete = 0;

        /* reset select flag */
        f->flag_isselect = 0;

        /* reset flushing flag */
        f->flag_flushing = 0;

        /* reset ASYNC proc flag */
        f->async_p = NULL;

        mtx_lock(&usb_ref_lock);
        /* flag the fifo as opened to prevent others */
        f->curr_cpd = cpd;
        mtx_unlock(&usb_ref_lock);

        /* reset queue */
        usb_fifo_reset(f);

        mtx_unlock(f->priv_mtx);
done:
        return (err);
}

/*------------------------------------------------------------------------*
 *      usb_fifo_reset
 *------------------------------------------------------------------------*/
void
usb_fifo_reset(struct usb_fifo *f)
{
        struct usb_mbuf *m;

        if (f == NULL) {
                return;
        }
        while (1) {
                USB_IF_DEQUEUE(&f->used_q, m);
                if (m) {
                        USB_IF_ENQUEUE(&f->free_q, m);
                } else {
                        break;
                }
        }
        /* reset have fragment flag */
        f->flag_have_fragment = 0;
}

/*------------------------------------------------------------------------*
 *      usb_fifo_close
 *------------------------------------------------------------------------*/
static void
usb_fifo_close(struct usb_fifo *f, int fflags)
{
        int err;

        /* check if we are not opened */
        if (f->curr_cpd == NULL) {
                /* nothing to do - already closed */
                return;
        }
        mtx_lock(f->priv_mtx);

        /* clear current cdev private data pointer */
        mtx_lock(&usb_ref_lock);
        f->curr_cpd = NULL;
        mtx_unlock(&usb_ref_lock);

        /* check if we are watched by kevent */
        KNOTE_LOCKED(&f->selinfo.si_note, 0);

        /* check if we are selected */
        if (f->flag_isselect) {
                selwakeup(&f->selinfo);
                f->flag_isselect = 0;
        }
        /* check if a thread wants SIGIO */
        if (f->async_p != NULL) {
                PROC_LOCK(f->async_p);
                kern_psignal(f->async_p, SIGIO);
                PROC_UNLOCK(f->async_p);
                f->async_p = NULL;
        }
        /* remove FWRITE and FREAD flags */
        fflags &= ~(FWRITE | FREAD);

        /* flush written data, if any */
        if ((f->fifo_index & 1) == USB_FIFO_TX) {

                if (!f->flag_iserror) {

                        /* set flushing flag */
                        f->flag_flushing = 1;

                        /* get the last packet in */
                        if (f->flag_have_fragment) {
                                struct usb_mbuf *m;
                                f->flag_have_fragment = 0;
                                USB_IF_DEQUEUE(&f->free_q, m);
                                if (m) {
                                        USB_IF_ENQUEUE(&f->used_q, m);
                                }
                        }

                        /* start write transfer, if not already started */
                        (f->methods->f_start_write) (f);

                        /* check if flushed already */
                        while (f->flag_flushing &&
                            (!f->flag_iserror)) {
                                /* wait until all data has been written */
                                f->flag_sleeping = 1;
                                err = cv_timedwait_sig(&f->cv_io, f->priv_mtx,
                                    USB_MS_TO_TICKS(USB_DEFAULT_TIMEOUT));
                                if (err) {
                                        DPRINTF("signal received\n");
                                        break;
                                }
                        }
                }
                fflags |= FWRITE;

                /* stop write transfer, if not already stopped */
                (f->methods->f_stop_write) (f);
        } else {
                fflags |= FREAD;

                /* stop write transfer, if not already stopped */
                (f->methods->f_stop_read) (f);
        }

        /* check if we are sleeping */
        if (f->flag_sleeping) {
                DPRINTFN(2, "Sleeping at close!\n");
        }
        mtx_unlock(f->priv_mtx);

        /* call close method */
        (f->methods->f_close) (f, fflags);

        DPRINTF("closed\n");
}

/*------------------------------------------------------------------------*
 *      usb_open - cdev callback
 *------------------------------------------------------------------------*/
static int
usb_open(struct cdev *dev, int fflags, int devtype, struct thread *td)
{
        struct usb_fs_privdata* pd = (struct usb_fs_privdata*)dev->si_drv1;
        struct usb_cdev_refdata refs;
        struct usb_cdev_privdata *cpd;
        int err, ep;

        DPRINTFN(2, "%s fflags=0x%08x\n", devtoname(dev), fflags);

        KASSERT(fflags & (FREAD|FWRITE), ("invalid open flags"));
        if (((fflags & FREAD) && !(pd->mode & FREAD)) ||
            ((fflags & FWRITE) && !(pd->mode & FWRITE))) {
                DPRINTFN(2, "access mode not supported\n");
                return (EPERM);
        }

        cpd = malloc(sizeof(*cpd), M_USBDEV, M_WAITOK | M_ZERO);
        ep = cpd->ep_addr = pd->ep_addr;

        usb_loc_fill(pd, cpd);
        err = usb_ref_device(cpd, &refs, 1);
        if (err) {
                DPRINTFN(2, "cannot ref device\n");
                free(cpd, M_USBDEV);
                return (ENXIO);
        }
        cpd->fflags = fflags;   /* access mode for open lifetime */

        /* create FIFOs, if any */
        err = usb_fifo_create(cpd, &refs);
        /* check for error */
        if (err) {
                DPRINTFN(2, "cannot create fifo\n");
                usb_unref_device(cpd, &refs);
                free(cpd, M_USBDEV);
                return (err);
        }
        if (fflags & FREAD) {
                err = usb_fifo_open(cpd, refs.rxfifo, fflags);
                if (err) {
                        DPRINTFN(2, "read open failed\n");
                        usb_unref_device(cpd, &refs);
                        free(cpd, M_USBDEV);
                        return (err);
                }
        }
        if (fflags & FWRITE) {
                err = usb_fifo_open(cpd, refs.txfifo, fflags);
                if (err) {
                        DPRINTFN(2, "write open failed\n");
                        if (fflags & FREAD) {
                                usb_fifo_close(refs.rxfifo, fflags);
                        }
                        usb_unref_device(cpd, &refs);
                        free(cpd, M_USBDEV);
                        return (err);
                }
        }
        usb_unref_device(cpd, &refs);
        devfs_set_cdevpriv(cpd, usb_close);

        return (0);
}

/*------------------------------------------------------------------------*
 *      usb_close - cdev callback
 *------------------------------------------------------------------------*/
static void
usb_close(void *arg)
{
        struct usb_cdev_refdata refs;
        struct usb_cdev_privdata *cpd = arg;
        int err;

        DPRINTFN(2, "cpd=%p\n", cpd);

        err = usb_ref_device(cpd, &refs,
            2 /* uref and allow detached state */);
        if (err) {
                DPRINTFN(2, "Cannot grab USB reference when "
                    "closing USB file handle\n");
                goto done;
        }
        if (cpd->fflags & FREAD) {
                usb_fifo_close(refs.rxfifo, cpd->fflags);
        }
        if (cpd->fflags & FWRITE) {
                usb_fifo_close(refs.txfifo, cpd->fflags);
        }
        usb_unref_device(cpd, &refs);
done:
        free(cpd, M_USBDEV);
}

static void
usb_dev_init(void *arg)
{
        mtx_init(&usb_ref_lock, "USB ref mutex", NULL, MTX_DEF);
        sx_init(&usb_sym_lock, "USB sym mutex");
        TAILQ_INIT(&usb_sym_head);

        /* check the UGEN methods */
        usb_fifo_check_methods(&usb_ugen_methods);
}

SYSINIT(usb_dev_init, SI_SUB_KLD, SI_ORDER_FIRST, usb_dev_init, NULL);

static void
usb_dev_init_post(void *arg)
{
        /*
         * Create /dev/usb - this is needed for usbconfig(8), which
         * needs a well-known device name to access.
         */
        usb_dev = make_dev(&usb_static_devsw, 0, UID_ROOT, GID_OPERATOR,
            0644, USB_DEVICE_NAME);
        if (usb_dev == NULL) {
                DPRINTFN(0, "Could not create usb bus device\n");
        }
}

SYSINIT(usb_dev_init_post, SI_SUB_KICK_SCHEDULER, SI_ORDER_FIRST, usb_dev_init_post, NULL);

static void
usb_dev_uninit(void *arg)
{
        if (usb_dev != NULL) {
                destroy_dev(usb_dev);
                usb_dev = NULL;
        }
        mtx_destroy(&usb_ref_lock);
        sx_destroy(&usb_sym_lock);
}

SYSUNINIT(usb_dev_uninit, SI_SUB_KICK_SCHEDULER, SI_ORDER_ANY, usb_dev_uninit, NULL);

static int
usb_ioctl_f_sub(struct usb_fifo *f, u_long cmd, void *addr,
    struct thread *td)
{
        int error = 0;

        switch (cmd) {
        case FIODTYPE:
                *(int *)addr = 0;       /* character device */
                break;

        case FIONBIO:
                /* handled by upper FS layer */
                break;

        case FIOASYNC:
                if (*(int *)addr) {
                        if (f->async_p != NULL) {
                                error = EBUSY;
                                break;
                        }
                        f->async_p = USB_TD_GET_PROC(td);
                } else {
                        f->async_p = NULL;
                }
                break;

                /* XXX this is not the most general solution */
        case TIOCSPGRP:
                if (f->async_p == NULL) {
                        error = EINVAL;
                        break;
                }
                if (*(int *)addr != USB_PROC_GET_GID(f->async_p)) {
                        error = EPERM;
                        break;
                }
                break;
        default:
                return (ENOIOCTL);
        }
        DPRINTFN(3, "cmd 0x%lx = %d\n", cmd, error);
        return (error);
}

/*------------------------------------------------------------------------*
 *      usb_ioctl - cdev callback
 *------------------------------------------------------------------------*/
static int
usb_ioctl(struct cdev *dev, u_long cmd, caddr_t addr, int fflag, struct thread* td)
{
        struct usb_cdev_refdata refs;
        struct usb_cdev_privdata* cpd;
        struct usb_fifo *f;
        int fflags;
        int err;

        DPRINTFN(2, "cmd=0x%lx\n", cmd);

        err = devfs_get_cdevpriv((void **)&cpd);
        if (err != 0)
                return (err);

        /* 
         * Performance optimisation: We try to check for IOCTL's that
         * don't need the USB reference first. Then we grab the USB
         * reference if we need it!
         */
        err = usb_ref_device(cpd, &refs, 0 /* no uref */ );
        if (err)
                return (ENXIO);

        fflags = cpd->fflags;

        f = NULL;                       /* set default value */
        err = ENOIOCTL;                 /* set default value */

        if (fflags & FWRITE) {
                f = refs.txfifo;
                err = usb_ioctl_f_sub(f, cmd, addr, td);
        }
        if (fflags & FREAD) {
                f = refs.rxfifo;
                err = usb_ioctl_f_sub(f, cmd, addr, td);
        }
        KASSERT(f != NULL, ("fifo not found"));
        if (err != ENOIOCTL)
                goto done;

        err = (f->methods->f_ioctl) (f, cmd, addr, fflags);

        DPRINTFN(2, "f_ioctl cmd 0x%lx = %d\n", cmd, err);

        if (err != ENOIOCTL)
                goto done;

        if (usb_usb_ref_device(cpd, &refs)) {
                /* we lost the reference */
                return (ENXIO);
        }

        err = (f->methods->f_ioctl_post) (f, cmd, addr, fflags);

        DPRINTFN(2, "f_ioctl_post cmd 0x%lx = %d\n", cmd, err);

        if (err == ENOIOCTL)
                err = ENOTTY;

        if (err)
                goto done;

        /* Wait for re-enumeration, if any */

        while (f->udev->re_enumerate_wait != USB_RE_ENUM_DONE) {

                usb_unref_device(cpd, &refs);

                usb_pause_mtx(NULL, hz / 128);

                while (usb_ref_device(cpd, &refs, 1 /* need uref */)) {
                        if (usb_ref_device(cpd, &refs, 0)) {
                                /* device no longer exists */
                                return (ENXIO);
                        }
                        usb_unref_device(cpd, &refs);
                        usb_pause_mtx(NULL, hz / 128);
                }
        }

done:
        usb_unref_device(cpd, &refs);
        return (err);
}

static void
usb_filter_detach(struct knote *kn)
{
        struct usb_fifo *f = kn->kn_hook;
        knlist_remove(&f->selinfo.si_note, kn, 0);
}

static int
usb_filter_write(struct knote *kn, long hint)
{
        struct usb_cdev_privdata* cpd;
        struct usb_fifo *f;
        struct usb_mbuf *m;

        DPRINTFN(2, "\n");

        f = kn->kn_hook;

        mtx_assert(f->priv_mtx, MA_OWNED);

        cpd = f->curr_cpd;
        if (cpd == NULL) {
                m = (void *)1;
        } else if (f->fs_ep_max == 0) {
                if (f->flag_iserror) {
                        /* we got an error */
                        m = (void *)1;
                } else {
                        if (f->queue_data == NULL) {
                                /*
                                 * start write transfer, if not
                                 * already started
                                 */
                                (f->methods->f_start_write) (f);
                        }
                        /* check if any packets are available */
                        USB_IF_POLL(&f->free_q, m);
                }
        } else {
                if (f->flag_iscomplete) {
                        m = (void *)1;
                } else {
                        m = NULL;
                }
        }
        return (m ? 1 : 0);
}

static int
usb_filter_read(struct knote *kn, long hint)
{
        struct usb_cdev_privdata* cpd;
        struct usb_fifo *f;
        struct usb_mbuf *m;

        DPRINTFN(2, "\n");

        f = kn->kn_hook;

        mtx_assert(f->priv_mtx, MA_OWNED);

        cpd = f->curr_cpd;
        if (cpd == NULL) {
                m = (void *)1;
        } else if (f->fs_ep_max == 0) {
                if (f->flag_iserror) {
                        /* we have an error */
                        m = (void *)1;
                } else {
                        if (f->queue_data == NULL) {
                                /*
                                 * start read transfer, if not
                                 * already started
                                 */
                                (f->methods->f_start_read) (f);
                        }
                        /* check if any packets are available */
                        USB_IF_POLL(&f->used_q, m);

                        /* start reading data, if any */
                        if (m == NULL)
                                (f->methods->f_start_read) (f);
                }
        } else {
                if (f->flag_iscomplete) {
                        m = (void *)1;
                } else {
                        m = NULL;
                }
        }
        return (m ? 1 : 0);
}

static struct filterops usb_filtops_write = {
        .f_isfd = 1,
        .f_detach = usb_filter_detach,
        .f_event = usb_filter_write,
};

static struct filterops usb_filtops_read = {
        .f_isfd = 1,
        .f_detach = usb_filter_detach,
        .f_event = usb_filter_read,
};


/* ARGSUSED */
static int
usb_kqfilter(struct cdev* dev, struct knote *kn)
{
        struct usb_cdev_refdata refs;
        struct usb_cdev_privdata* cpd;
        struct usb_fifo *f;
        int fflags;
        int err = EINVAL;

        DPRINTFN(2, "\n");

        if (devfs_get_cdevpriv((void **)&cpd) != 0 ||
            usb_ref_device(cpd, &refs, 0) != 0)
                return (ENXIO);

        fflags = cpd->fflags;

        /* Figure out who needs service */
        switch (kn->kn_filter) {
        case EVFILT_WRITE:
                if (fflags & FWRITE) {
                        f = refs.txfifo;
                        kn->kn_fop = &usb_filtops_write;
                        err = 0;
                }
                break;
        case EVFILT_READ:
                if (fflags & FREAD) {
                        f = refs.rxfifo;
                        kn->kn_fop = &usb_filtops_read;
                        err = 0;
                }
                break;
        default:
                err = EOPNOTSUPP;
                break;
        }

        if (err == 0) {
                kn->kn_hook = f;
                mtx_lock(f->priv_mtx);
                knlist_add(&f->selinfo.si_note, kn, 1);
                mtx_unlock(f->priv_mtx);
        }

        usb_unref_device(cpd, &refs);
        return (err);
}

/* ARGSUSED */
static int
usb_poll(struct cdev* dev, int events, struct thread* td)
{
        struct usb_cdev_refdata refs;
        struct usb_cdev_privdata* cpd;
        struct usb_fifo *f;
        struct usb_mbuf *m;
        int fflags, revents;

        if (devfs_get_cdevpriv((void **)&cpd) != 0 ||
            usb_ref_device(cpd, &refs, 0) != 0)
                return (events &
                    (POLLHUP|POLLIN|POLLRDNORM|POLLOUT|POLLWRNORM));

        fflags = cpd->fflags;

        /* Figure out who needs service */
        revents = 0;
        if ((events & (POLLOUT | POLLWRNORM)) &&
            (fflags & FWRITE)) {

                f = refs.txfifo;

                mtx_lock(f->priv_mtx);

                if (!refs.is_usbfs) {
                        if (f->flag_iserror) {
                                /* we got an error */
                                m = (void *)1;
                        } else {
                                if (f->queue_data == NULL) {
                                        /*
                                         * start write transfer, if not
                                         * already started
                                         */
                                        (f->methods->f_start_write) (f);
                                }
                                /* check if any packets are available */
                                USB_IF_POLL(&f->free_q, m);
                        }
                } else {
                        if (f->flag_iscomplete) {
                                m = (void *)1;
                        } else {
                                m = NULL;
                        }
                }

                if (m) {
                        revents |= events & (POLLOUT | POLLWRNORM);
                } else {
                        f->flag_isselect = 1;
                        selrecord(td, &f->selinfo);
                }

                mtx_unlock(f->priv_mtx);
        }
        if ((events & (POLLIN | POLLRDNORM)) &&
            (fflags & FREAD)) {

                f = refs.rxfifo;

                mtx_lock(f->priv_mtx);

                if (!refs.is_usbfs) {
                        if (f->flag_iserror) {
                                /* we have an error */
                                m = (void *)1;
                        } else {
                                if (f->queue_data == NULL) {
                                        /*
                                         * start read transfer, if not
                                         * already started
                                         */
                                        (f->methods->f_start_read) (f);
                                }
                                /* check if any packets are available */
                                USB_IF_POLL(&f->used_q, m);
                        }
                } else {
                        if (f->flag_iscomplete) {
                                m = (void *)1;
                        } else {
                                m = NULL;
                        }
                }

                if (m) {
                        revents |= events & (POLLIN | POLLRDNORM);
                } else {
                        f->flag_isselect = 1;
                        selrecord(td, &f->selinfo);

                        if (!refs.is_usbfs) {
                                /* start reading data */
                                (f->methods->f_start_read) (f);
                        }
                }

                mtx_unlock(f->priv_mtx);
        }
        usb_unref_device(cpd, &refs);
        return (revents);
}

static int
usb_read(struct cdev *dev, struct uio *uio, int ioflag)
{
        struct usb_cdev_refdata refs;
        struct usb_cdev_privdata* cpd;
        struct usb_fifo *f;
        struct usb_mbuf *m;
        int fflags;
        int resid;
        int io_len;
        int err;
        uint8_t tr_data = 0;

        err = devfs_get_cdevpriv((void **)&cpd);
        if (err != 0)
                return (err);

        err = usb_ref_device(cpd, &refs, 0 /* no uref */ );
        if (err)
                return (ENXIO);

        fflags = cpd->fflags;

        f = refs.rxfifo;
        if (f == NULL) {
                /* should not happen */
                usb_unref_device(cpd, &refs);
                return (EPERM);
        }

        resid = uio->uio_resid;

        mtx_lock(f->priv_mtx);

        /* check for permanent read error */
        if (f->flag_iserror) {
                err = EIO;
                goto done;
        }
        /* check if USB-FS interface is active */
        if (refs.is_usbfs) {
                /*
                 * The queue is used for events that should be
                 * retrieved using the "USB_FS_COMPLETE" ioctl.
                 */
                err = EINVAL;
                goto done;
        }
        while (uio->uio_resid > 0) {

                USB_IF_DEQUEUE(&f->used_q, m);

                if (m == NULL) {

                        /* start read transfer, if not already started */

                        (f->methods->f_start_read) (f);

                        if (ioflag & IO_NDELAY) {
                                if (tr_data) {
                                        /* return length before error */
                                        break;
                                }
                                err = EWOULDBLOCK;
                                break;
                        }
                        DPRINTF("sleeping\n");

                        err = usb_fifo_wait(f);
                        if (err) {
                                break;
                        }
                        continue;
                }
                if (f->methods->f_filter_read) {
                        /*
                         * Sometimes it is convenient to process data at the
                         * expense of a userland process instead of a kernel
                         * process.
                         */
                        (f->methods->f_filter_read) (f, m);
                }
                tr_data = 1;

                io_len = MIN(m->cur_data_len, uio->uio_resid);

                DPRINTFN(2, "transfer %d bytes from %p\n",
                    io_len, m->cur_data_ptr);

                err = usb_fifo_uiomove(f,
                    m->cur_data_ptr, io_len, uio);

                m->cur_data_len -= io_len;
                m->cur_data_ptr += io_len;

                if (m->cur_data_len == 0) {

                        uint8_t last_packet;

                        last_packet = m->last_packet;

                        USB_IF_ENQUEUE(&f->free_q, m);

                        if (last_packet) {
                                /* keep framing */
                                break;
                        }
                } else {
                        USB_IF_PREPEND(&f->used_q, m);
                }

                if (err) {
                        break;
                }
        }
done:
        mtx_unlock(f->priv_mtx);

        usb_unref_device(cpd, &refs);

        return (err);
}

static int
usb_write(struct cdev *dev, struct uio *uio, int ioflag)
{
        struct usb_cdev_refdata refs;
        struct usb_cdev_privdata* cpd;
        struct usb_fifo *f;
        struct usb_mbuf *m;
        uint8_t *pdata;
        int fflags;
        int resid;
        int io_len;
        int err;
        uint8_t tr_data = 0;

        DPRINTFN(2, "\n");

        err = devfs_get_cdevpriv((void **)&cpd);
        if (err != 0)
                return (err);

        err = usb_ref_device(cpd, &refs, 0 /* no uref */ );
        if (err)
                return (ENXIO);

        fflags = cpd->fflags;

        f = refs.txfifo;
        if (f == NULL) {
                /* should not happen */
                usb_unref_device(cpd, &refs);
                return (EPERM);
        }
        resid = uio->uio_resid;

        mtx_lock(f->priv_mtx);

        /* check for permanent write error */
        if (f->flag_iserror) {
                err = EIO;
                goto done;
        }
        /* check if USB-FS interface is active */
        if (refs.is_usbfs) {
                /*
                 * The queue is used for events that should be
                 * retrieved using the "USB_FS_COMPLETE" ioctl.
                 */
                err = EINVAL;
                goto done;
        }
        if (f->queue_data == NULL) {
                /* start write transfer, if not already started */
                (f->methods->f_start_write) (f);
        }
        /* we allow writing zero length data */
        do {
                USB_IF_DEQUEUE(&f->free_q, m);

                if (m == NULL) {

                        if (ioflag & IO_NDELAY) {
                                if (tr_data) {
                                        /* return length before error */
                                        break;
                                }
                                err = EWOULDBLOCK;
                                break;
                        }
                        DPRINTF("sleeping\n");

                        err = usb_fifo_wait(f);
                        if (err) {
                                break;
                        }
                        continue;
                }
                tr_data = 1;

                if (f->flag_have_fragment == 0) {
                        USB_MBUF_RESET(m);
                        io_len = m->cur_data_len;
                        pdata = m->cur_data_ptr;
                        if (io_len > uio->uio_resid)
                                io_len = uio->uio_resid;
                        m->cur_data_len = io_len;
                } else {
                        io_len = m->max_data_len - m->cur_data_len;
                        pdata = m->cur_data_ptr + m->cur_data_len;
                        if (io_len > uio->uio_resid)
                                io_len = uio->uio_resid;
                        m->cur_data_len += io_len;
                }

                DPRINTFN(2, "transfer %d bytes to %p\n",
                    io_len, pdata);

                err = usb_fifo_uiomove(f, pdata, io_len, uio);

                if (err) {
                        f->flag_have_fragment = 0;
                        USB_IF_ENQUEUE(&f->free_q, m);
                        break;
                }

                /* check if the buffer is ready to be transmitted */

                if ((f->flag_write_defrag == 0) ||
                    (m->cur_data_len == m->max_data_len)) {
                        f->flag_have_fragment = 0;

                        /*
                         * Check for write filter:
                         *
                         * Sometimes it is convenient to process data
                         * at the expense of a userland process
                         * instead of a kernel process.
                         */
                        if (f->methods->f_filter_write) {
                                (f->methods->f_filter_write) (f, m);
                        }

                        /* Put USB mbuf in the used queue */
                        USB_IF_ENQUEUE(&f->used_q, m);

                        /* Start writing data, if not already started */
                        (f->methods->f_start_write) (f);
                } else {
                        /* Wait for more data or close */
                        f->flag_have_fragment = 1;
                        USB_IF_PREPEND(&f->free_q, m);
                }

        } while (uio->uio_resid > 0);
done:
        mtx_unlock(f->priv_mtx);

        usb_unref_device(cpd, &refs);

        return (err);
}

int
usb_static_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
    struct thread *td)
{
        union {
                struct usb_read_dir *urd;
                void* data;
        } u;
        int err;

        u.data = data;
        switch (cmd) {
                case USB_READ_DIR:
                        err = usb_read_symlink(u.urd->urd_data,
                            u.urd->urd_startentry, u.urd->urd_maxlen);
                        break;
                case USB_DEV_QUIRK_GET:
                case USB_QUIRK_NAME_GET:
                case USB_DEV_QUIRK_ADD:
                case USB_DEV_QUIRK_REMOVE:
                        err = usb_quirk_ioctl_p(cmd, data, fflag, td);
                        break;
                case USB_GET_TEMPLATE:
                        *(int *)data = usb_template;
                        err = 0;
                        break;
                case USB_SET_TEMPLATE:
                        err = priv_check(curthread, PRIV_DRIVER);
                        if (err)
                                break;
                        usb_template = *(int *)data;
                        break;
                default:
                        err = ENOTTY;
                        break;
        }
        return (err);
}

static int
usb_fifo_uiomove(struct usb_fifo *f, void *cp,
    int n, struct uio *uio)
{
        int error;

        mtx_unlock(f->priv_mtx);

        /*
         * "uiomove()" can sleep so one needs to make a wrapper,
         * exiting the mutex and checking things:
         */
        error = uiomove(cp, n, uio);

        mtx_lock(f->priv_mtx);

        return (error);
}

int
usb_fifo_wait(struct usb_fifo *f)
{
        int err;

        mtx_assert(f->priv_mtx, MA_OWNED);

        if (f->flag_iserror) {
                /* we are gone */
                return (EIO);
        }
        f->flag_sleeping = 1;

        err = cv_wait_sig(&f->cv_io, f->priv_mtx);

        if (f->flag_iserror) {
                /* we are gone */
                err = EIO;
        }
        return (err);
}

void
usb_fifo_signal(struct usb_fifo *f)
{
        if (f->flag_sleeping) {
                f->flag_sleeping = 0;
                cv_broadcast(&f->cv_io);
        }
}

void
usb_fifo_wakeup(struct usb_fifo *f)
{
        usb_fifo_signal(f);

        KNOTE_LOCKED(&f->selinfo.si_note, 0);

        if (f->flag_isselect) {
                selwakeup(&f->selinfo);
                f->flag_isselect = 0;
        }
        if (f->async_p != NULL) {
                PROC_LOCK(f->async_p);
                kern_psignal(f->async_p, SIGIO);
                PROC_UNLOCK(f->async_p);
        }
}

static int
usb_fifo_dummy_open(struct usb_fifo *fifo, int fflags)
{
        return (0);
}

static void
usb_fifo_dummy_close(struct usb_fifo *fifo, int fflags)
{
        return;
}

static int
usb_fifo_dummy_ioctl(struct usb_fifo *fifo, u_long cmd, void *addr, int fflags)
{
        return (ENOIOCTL);
}

static void
usb_fifo_dummy_cmd(struct usb_fifo *fifo)
{
        fifo->flag_flushing = 0;        /* not flushing */
}

static void
usb_fifo_check_methods(struct usb_fifo_methods *pm)
{
        /* check that all callback functions are OK */

        if (pm->f_open == NULL)
                pm->f_open = &usb_fifo_dummy_open;

        if (pm->f_close == NULL)
                pm->f_close = &usb_fifo_dummy_close;

        if (pm->f_ioctl == NULL)
                pm->f_ioctl = &usb_fifo_dummy_ioctl;

        if (pm->f_ioctl_post == NULL)
                pm->f_ioctl_post = &usb_fifo_dummy_ioctl;

        if (pm->f_start_read == NULL)
                pm->f_start_read = &usb_fifo_dummy_cmd;

        if (pm->f_stop_read == NULL)
                pm->f_stop_read = &usb_fifo_dummy_cmd;

        if (pm->f_start_write == NULL)
                pm->f_start_write = &usb_fifo_dummy_cmd;

        if (pm->f_stop_write == NULL)
                pm->f_stop_write = &usb_fifo_dummy_cmd;
}

/*------------------------------------------------------------------------*
 *      usb_fifo_attach
 *
 * The following function will create a duplex FIFO.
 *
 * Return values:
 * 0: Success.
 * Else: Failure.
 *------------------------------------------------------------------------*/
int
usb_fifo_attach(struct usb_device *udev, void *priv_sc,
    struct mtx *priv_mtx, struct usb_fifo_methods *pm,
    struct usb_fifo_sc *f_sc, uint16_t unit, int16_t subunit,
    uint8_t iface_index, uid_t uid, gid_t gid, int mode)
{
        struct usb_fifo *f_tx;
        struct usb_fifo *f_rx;
        char devname[32];
        uint8_t n;

        f_sc->fp[USB_FIFO_TX] = NULL;
        f_sc->fp[USB_FIFO_RX] = NULL;

        if (pm == NULL)
                return (EINVAL);

        /* check the methods */
        usb_fifo_check_methods(pm);

        if (priv_mtx == NULL)
                priv_mtx = &Giant;

        /* search for a free FIFO slot */
        for (n = 0;; n += 2) {

                if (n == USB_FIFO_MAX) {
                        /* end of FIFOs reached */
                        return (ENOMEM);
                }
                /* Check for TX FIFO */
                if (udev->fifo[n + USB_FIFO_TX] != NULL) {
                        continue;
                }
                /* Check for RX FIFO */
                if (udev->fifo[n + USB_FIFO_RX] != NULL) {
                        continue;
                }
                break;
        }

        f_tx = usb_fifo_alloc(priv_mtx);
        f_rx = usb_fifo_alloc(priv_mtx);

        if ((f_tx == NULL) || (f_rx == NULL)) {
                usb_fifo_free(f_tx);
                usb_fifo_free(f_rx);
                return (ENOMEM);
        }
        /* initialise FIFO structures */

        f_tx->fifo_index = n + USB_FIFO_TX;
        f_tx->dev_ep_index = -1;
        f_tx->priv_sc0 = priv_sc;
        f_tx->methods = pm;
        f_tx->iface_index = iface_index;
        f_tx->udev = udev;

        f_rx->fifo_index = n + USB_FIFO_RX;
        f_rx->dev_ep_index = -1;
        f_rx->priv_sc0 = priv_sc;
        f_rx->methods = pm;
        f_rx->iface_index = iface_index;
        f_rx->udev = udev;

        f_sc->fp[USB_FIFO_TX] = f_tx;
        f_sc->fp[USB_FIFO_RX] = f_rx;

        mtx_lock(&usb_ref_lock);
        udev->fifo[f_tx->fifo_index] = f_tx;
        udev->fifo[f_rx->fifo_index] = f_rx;
        mtx_unlock(&usb_ref_lock);

        for (n = 0; n != 4; n++) {

                if (pm->basename[n] == NULL) {
                        continue;
                }
                if (subunit < 0) {
                        if (snprintf(devname, sizeof(devname),
                            "%s%u%s", pm->basename[n],
                            unit, pm->postfix[n] ?
                            pm->postfix[n] : "")) {
                                /* ignore */
                        }
                } else {
                        if (snprintf(devname, sizeof(devname),
                            "%s%u.%d%s", pm->basename[n],
                            unit, subunit, pm->postfix[n] ?
                            pm->postfix[n] : "")) {
                                /* ignore */
                        }
                }

                /*
                 * Distribute the symbolic links into two FIFO structures:
                 */
                if (n & 1) {
                        f_rx->symlink[n / 2] =
                            usb_alloc_symlink(devname);
                } else {
                        f_tx->symlink[n / 2] =
                            usb_alloc_symlink(devname);
                }

                /* Create the device */
                f_sc->dev = usb_make_dev(udev, devname, -1,
                    f_tx->fifo_index & f_rx->fifo_index,
                    FREAD|FWRITE, uid, gid, mode);
        }

        DPRINTFN(2, "attached %p/%p\n", f_tx, f_rx);
        return (0);
}

/*------------------------------------------------------------------------*
 *      usb_fifo_alloc_buffer
 *
 * Return values:
 * 0: Success
 * Else failure
 *------------------------------------------------------------------------*/
int
usb_fifo_alloc_buffer(struct usb_fifo *f, usb_size_t bufsize,
    uint16_t nbuf)
{
        usb_fifo_free_buffer(f);

        /* allocate an endpoint */
        f->free_q.ifq_maxlen = nbuf;
        f->used_q.ifq_maxlen = nbuf;

        f->queue_data = usb_alloc_mbufs(
            M_USBDEV, &f->free_q, bufsize, nbuf);

        if ((f->queue_data == NULL) && bufsize && nbuf) {
                return (ENOMEM);
        }
        return (0);                     /* success */
}

/*------------------------------------------------------------------------*
 *      usb_fifo_free_buffer
 *
 * This function will free the buffers associated with a FIFO. This
 * function can be called multiple times in a row.
 *------------------------------------------------------------------------*/
void
usb_fifo_free_buffer(struct usb_fifo *f)
{
        if (f->queue_data) {
                /* free old buffer */
                free(f->queue_data, M_USBDEV);
                f->queue_data = NULL;
        }
        /* reset queues */

        memset(&f->free_q, 0, sizeof(f->free_q));
        memset(&f->used_q, 0, sizeof(f->used_q));
}

void
usb_fifo_detach(struct usb_fifo_sc *f_sc)
{
        if (f_sc == NULL) {
                return;
        }
        usb_fifo_free(f_sc->fp[USB_FIFO_TX]);
        usb_fifo_free(f_sc->fp[USB_FIFO_RX]);

        f_sc->fp[USB_FIFO_TX] = NULL;
        f_sc->fp[USB_FIFO_RX] = NULL;

        usb_destroy_dev(f_sc->dev);

        f_sc->dev = NULL;

        DPRINTFN(2, "detached %p\n", f_sc);
}

usb_size_t
usb_fifo_put_bytes_max(struct usb_fifo *f)
{
        struct usb_mbuf *m;
        usb_size_t len;

        USB_IF_POLL(&f->free_q, m);

        if (m) {
                len = m->max_data_len;
        } else {
                len = 0;
        }
        return (len);
}

/*------------------------------------------------------------------------*
 *      usb_fifo_put_data
 *
 * what:
 *  0 - normal operation
 *  1 - set last packet flag to enforce framing
 *------------------------------------------------------------------------*/
void
usb_fifo_put_data(struct usb_fifo *f, struct usb_page_cache *pc,
    usb_frlength_t offset, usb_frlength_t len, uint8_t what)
{
        struct usb_mbuf *m;
        usb_frlength_t io_len;

        while (len || (what == 1)) {

                USB_IF_DEQUEUE(&f->free_q, m);

                if (m) {
                        USB_MBUF_RESET(m);

                        io_len = MIN(len, m->cur_data_len);

                        usbd_copy_out(pc, offset, m->cur_data_ptr, io_len);

                        m->cur_data_len = io_len;
                        offset += io_len;
                        len -= io_len;

                        if ((len == 0) && (what == 1)) {
                                m->last_packet = 1;
                        }
                        USB_IF_ENQUEUE(&f->used_q, m);

                        usb_fifo_wakeup(f);

                        if ((len == 0) || (what == 1)) {
                                break;
                        }
                } else {
                        break;
                }
        }
}

void
usb_fifo_put_data_linear(struct usb_fifo *f, void *ptr,
    usb_size_t len, uint8_t what)
{
        struct usb_mbuf *m;
        usb_size_t io_len;

        while (len || (what == 1)) {

                USB_IF_DEQUEUE(&f->free_q, m);

                if (m) {
                        USB_MBUF_RESET(m);

                        io_len = MIN(len, m->cur_data_len);

                        memcpy(m->cur_data_ptr, ptr, io_len);

                        m->cur_data_len = io_len;
                        ptr = USB_ADD_BYTES(ptr, io_len);
                        len -= io_len;

                        if ((len == 0) && (what == 1)) {
                                m->last_packet = 1;
                        }
                        USB_IF_ENQUEUE(&f->used_q, m);

                        usb_fifo_wakeup(f);

                        if ((len == 0) || (what == 1)) {
                                break;
                        }
                } else {
                        break;
                }
        }
}

uint8_t
usb_fifo_put_data_buffer(struct usb_fifo *f, void *ptr, usb_size_t len)
{
        struct usb_mbuf *m;

        USB_IF_DEQUEUE(&f->free_q, m);

        if (m) {
                m->cur_data_len = len;
                m->cur_data_ptr = ptr;
                USB_IF_ENQUEUE(&f->used_q, m);
                usb_fifo_wakeup(f);
                return (1);
        }
        return (0);
}

void
usb_fifo_put_data_error(struct usb_fifo *f)
{
        f->flag_iserror = 1;
        usb_fifo_wakeup(f);
}

/*------------------------------------------------------------------------*
 *      usb_fifo_get_data
 *
 * what:
 *  0 - normal operation
 *  1 - only get one "usb_mbuf"
 *
 * returns:
 *  0 - no more data
 *  1 - data in buffer
 *------------------------------------------------------------------------*/
uint8_t
usb_fifo_get_data(struct usb_fifo *f, struct usb_page_cache *pc,
    usb_frlength_t offset, usb_frlength_t len, usb_frlength_t *actlen,
    uint8_t what)
{
        struct usb_mbuf *m;
        usb_frlength_t io_len;
        uint8_t tr_data = 0;

        actlen[0] = 0;

        while (1) {

                USB_IF_DEQUEUE(&f->used_q, m);

                if (m) {

                        tr_data = 1;

                        io_len = MIN(len, m->cur_data_len);

                        usbd_copy_in(pc, offset, m->cur_data_ptr, io_len);

                        len -= io_len;
                        offset += io_len;
                        actlen[0] += io_len;
                        m->cur_data_ptr += io_len;
                        m->cur_data_len -= io_len;

                        if ((m->cur_data_len == 0) || (what == 1)) {
                                USB_IF_ENQUEUE(&f->free_q, m);

                                usb_fifo_wakeup(f);

                                if (what == 1) {
                                        break;
                                }
                        } else {
                                USB_IF_PREPEND(&f->used_q, m);
                        }
                } else {

                        if (tr_data) {
                                /* wait for data to be written out */
                                break;
                        }
                        if (f->flag_flushing) {
                                /* check if we should send a short packet */
                                if (f->flag_short != 0) {
                                        f->flag_short = 0;
                                        tr_data = 1;
                                        break;
                                }
                                /* flushing complete */
                                f->flag_flushing = 0;
                                usb_fifo_wakeup(f);
                        }
                        break;
                }
                if (len == 0) {
                        break;
                }
        }
        return (tr_data);
}

uint8_t
usb_fifo_get_data_linear(struct usb_fifo *f, void *ptr,
    usb_size_t len, usb_size_t *actlen, uint8_t what)
{
        struct usb_mbuf *m;
        usb_size_t io_len;
        uint8_t tr_data = 0;

        actlen[0] = 0;

        while (1) {

                USB_IF_DEQUEUE(&f->used_q, m);

                if (m) {

                        tr_data = 1;

                        io_len = MIN(len, m->cur_data_len);

                        memcpy(ptr, m->cur_data_ptr, io_len);

                        len -= io_len;
                        ptr = USB_ADD_BYTES(ptr, io_len);
                        actlen[0] += io_len;
                        m->cur_data_ptr += io_len;
                        m->cur_data_len -= io_len;

                        if ((m->cur_data_len == 0) || (what == 1)) {
                                USB_IF_ENQUEUE(&f->free_q, m);

                                usb_fifo_wakeup(f);

                                if (what == 1) {
                                        break;
                                }
                        } else {
                                USB_IF_PREPEND(&f->used_q, m);
                        }
                } else {

                        if (tr_data) {
                                /* wait for data to be written out */
                                break;
                        }
                        if (f->flag_flushing) {
                                /* check if we should send a short packet */
                                if (f->flag_short != 0) {
                                        f->flag_short = 0;
                                        tr_data = 1;
                                        break;
                                }
                                /* flushing complete */
                                f->flag_flushing = 0;
                                usb_fifo_wakeup(f);
                        }
                        break;
                }
                if (len == 0) {
                        break;
                }
        }
        return (tr_data);
}

uint8_t
usb_fifo_get_data_buffer(struct usb_fifo *f, void **pptr, usb_size_t *plen)
{
        struct usb_mbuf *m;

        USB_IF_POLL(&f->used_q, m);

        if (m) {
                *plen = m->cur_data_len;
                *pptr = m->cur_data_ptr;

                return (1);
        }
        return (0);
}

void
usb_fifo_get_data_error(struct usb_fifo *f)
{
        f->flag_iserror = 1;
        usb_fifo_wakeup(f);
}

/*------------------------------------------------------------------------*
 *      usb_alloc_symlink
 *
 * Return values:
 * NULL: Failure
 * Else: Pointer to symlink entry
 *------------------------------------------------------------------------*/
struct usb_symlink *
usb_alloc_symlink(const char *target)
{
        struct usb_symlink *ps;

        ps = malloc(sizeof(*ps), M_USBDEV, M_WAITOK);
        if (ps == NULL) {
                return (ps);
        }
        /* XXX no longer needed */
        strlcpy(ps->src_path, target, sizeof(ps->src_path));
        ps->src_len = strlen(ps->src_path);
        strlcpy(ps->dst_path, target, sizeof(ps->dst_path));
        ps->dst_len = strlen(ps->dst_path);

        sx_xlock(&usb_sym_lock);
        TAILQ_INSERT_TAIL(&usb_sym_head, ps, sym_entry);
        sx_unlock(&usb_sym_lock);
        return (ps);
}

/*------------------------------------------------------------------------*
 *      usb_free_symlink
 *------------------------------------------------------------------------*/
void
usb_free_symlink(struct usb_symlink *ps)
{
        if (ps == NULL) {
                return;
        }
        sx_xlock(&usb_sym_lock);
        TAILQ_REMOVE(&usb_sym_head, ps, sym_entry);
        sx_unlock(&usb_sym_lock);

        free(ps, M_USBDEV);
}

/*------------------------------------------------------------------------*
 *      usb_read_symlink
 *
 * Return value:
 * 0: Success
 * Else: Failure
 *------------------------------------------------------------------------*/
int
usb_read_symlink(uint8_t *user_ptr, uint32_t startentry, uint32_t user_len)
{
        struct usb_symlink *ps;
        uint32_t temp;
        uint32_t delta = 0;
        uint8_t len;
        int error = 0;

        sx_xlock(&usb_sym_lock);

        TAILQ_FOREACH(ps, &usb_sym_head, sym_entry) {

                /*
                 * Compute total length of source and destination symlink
                 * strings pluss one length byte and two NUL bytes:
                 */
                temp = ps->src_len + ps->dst_len + 3;

                if (temp > 255) {
                        /*
                         * Skip entry because this length cannot fit
                         * into one byte:
                         */
                        continue;
                }
                if (startentry != 0) {
                        /* decrement read offset */
                        startentry--;
                        continue;
                }
                if (temp > user_len) {
                        /* out of buffer space */
                        break;
                }
                len = temp;

                /* copy out total length */

                error = copyout(&len,
                    USB_ADD_BYTES(user_ptr, delta), 1);
                if (error) {
                        break;
                }
                delta += 1;

                /* copy out source string */

                error = copyout(ps->src_path,
                    USB_ADD_BYTES(user_ptr, delta), ps->src_len);
                if (error) {
                        break;
                }
                len = 0;
                delta += ps->src_len;
                error = copyout(&len,
                    USB_ADD_BYTES(user_ptr, delta), 1);
                if (error) {
                        break;
                }
                delta += 1;

                /* copy out destination string */

                error = copyout(ps->dst_path,
                    USB_ADD_BYTES(user_ptr, delta), ps->dst_len);
                if (error) {
                        break;
                }
                len = 0;
                delta += ps->dst_len;
                error = copyout(&len,
                    USB_ADD_BYTES(user_ptr, delta), 1);
                if (error) {
                        break;
                }
                delta += 1;

                user_len -= temp;
        }

        /* a zero length entry indicates the end */

        if ((user_len != 0) && (error == 0)) {

                len = 0;

                error = copyout(&len,
                    USB_ADD_BYTES(user_ptr, delta), 1);
        }
        sx_unlock(&usb_sym_lock);
        return (error);
}

void
usb_fifo_set_close_zlp(struct usb_fifo *f, uint8_t onoff)
{
        if (f == NULL)
                return;

        /* send a Zero Length Packet, ZLP, before close */
        f->flag_short = onoff;
}

void
usb_fifo_set_write_defrag(struct usb_fifo *f, uint8_t onoff)
{
        if (f == NULL)
                return;

        /* defrag written data */
        f->flag_write_defrag = onoff;
        /* reset defrag state */
        f->flag_have_fragment = 0;
}

void *
usb_fifo_softc(struct usb_fifo *f)
{
        return (f->priv_sc0);
}
#endif  /* USB_HAVE_UGEN */