/* $FreeBSD: head/sys/dev/usb/usb_generic.c 277417 2015-01-20 11:43:16Z hselasky $ */
/*-
 * Copyright (c) 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.
 */

#include <sys/stdint.h>
#include <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 <sys/lock.h>
#include <sys/condvar.h>
#include <sys/sysctl.h>
#include <sys/unistd.h>
#include <sys/callout.h>
#include <sys/malloc.h>
#include <sys/caps.h>
#include <sys/conf.h>
#include <sys/fcntl.h>

#include <bus/u4b/usb.h>
#include <bus/u4b/usb_ioctl.h>
#include <bus/u4b/usbdi.h>
#include <bus/u4b/usbdi_util.h>

#define USB_DEBUG_VAR ugen_debug

#include <bus/u4b/usb_core.h>
#include <bus/u4b/usb_dev.h>
#include <bus/u4b/usb_mbuf.h>
#include <bus/u4b/usb_process.h>
#include <bus/u4b/usb_device.h>
#include <bus/u4b/usb_debug.h>
#include <bus/u4b/usb_request.h>
#include <bus/u4b/usb_busdma.h>
#include <bus/u4b/usb_util.h>
#include <bus/u4b/usb_hub.h>
#include <bus/u4b/usb_generic.h>
#include <bus/u4b/usb_transfer.h>

#include <bus/u4b/usb_controller.h>
#include <bus/u4b/usb_bus.h>

#if USB_HAVE_UGEN

/* defines */

#define UGEN_BULK_FS_BUFFER_SIZE        (64*32) /* bytes */
#define UGEN_BULK_HS_BUFFER_SIZE        (1024*32)       /* bytes */
#define UGEN_HW_FRAMES  50              /* number of milliseconds per transfer */

/* function prototypes */

static usb_callback_t ugen_read_clear_stall_callback;
static usb_callback_t ugen_write_clear_stall_callback;
static usb_callback_t ugen_ctrl_read_callback;
static usb_callback_t ugen_ctrl_write_callback;
static usb_callback_t ugen_isoc_read_callback;
static usb_callback_t ugen_isoc_write_callback;
static usb_callback_t ugen_ctrl_fs_callback;

static usb_fifo_open_t ugen_open;
static usb_fifo_close_t ugen_close;
static usb_fifo_ioctl_t ugen_ioctl;
static usb_fifo_ioctl_t ugen_ioctl_post;
static usb_fifo_cmd_t ugen_start_read;
static usb_fifo_cmd_t ugen_start_write;
static usb_fifo_cmd_t ugen_stop_io;

static int      ugen_transfer_setup(struct usb_fifo *,
                     const struct usb_config *, uint8_t);
static int      ugen_open_pipe_write(struct usb_fifo *);
static int      ugen_open_pipe_read(struct usb_fifo *);
static int      ugen_set_config(struct usb_fifo *, uint8_t);
static int      ugen_set_interface(struct usb_fifo *, uint8_t, uint8_t);
static int      ugen_get_cdesc(struct usb_fifo *, struct usb_gen_descriptor *);
static int      ugen_get_sdesc(struct usb_fifo *, struct usb_gen_descriptor *);
static int      ugen_get_iface_driver(struct usb_fifo *f, struct usb_gen_descriptor *ugd);
static int      usb_gen_fill_deviceinfo(struct usb_fifo *,
                    struct usb_device_info *);
static int      ugen_re_enumerate(struct usb_fifo *);
static int      ugen_iface_ioctl(struct usb_fifo *, u_long, void *, int);
static uint8_t  ugen_fs_get_complete(struct usb_fifo *, uint8_t *);
static int      ugen_fs_uninit(struct usb_fifo *f);

/* structures */

struct usb_fifo_methods usb_ugen_methods = {
        .f_open = &ugen_open,
        .f_close = &ugen_close,
        .f_ioctl = &ugen_ioctl,
        .f_ioctl_post = &ugen_ioctl_post,
        .f_start_read = &ugen_start_read,
        .f_stop_read = &ugen_stop_io,
        .f_start_write = &ugen_start_write,
        .f_stop_write = &ugen_stop_io,
};

#ifdef USB_DEBUG
static int ugen_debug = 0;

static SYSCTL_NODE(_hw_usb, OID_AUTO, ugen, CTLFLAG_RW, 0, "USB generic");
SYSCTL_INT(_hw_usb_ugen, OID_AUTO, debug, CTLFLAG_RW, &ugen_debug,
    0, "Debug level");

TUNABLE_INT("hw.usb.ugen.debug", &ugen_debug);
#endif


/* prototypes */

static int
ugen_transfer_setup(struct usb_fifo *f,
    const struct usb_config *setup, uint8_t n_setup)
{
        struct usb_endpoint *ep = usb_fifo_softc(f);
        struct usb_device *udev = f->udev;
        uint8_t iface_index = ep->iface_index;
        int error;

        lockmgr(f->priv_lock, LK_RELEASE);

        /*
         * "usbd_transfer_setup()" can sleep so one needs to make a wrapper,
         * exiting the mutex and checking things
         */
        error = usbd_transfer_setup(udev, &iface_index, f->xfer,
            setup, n_setup, f, f->priv_lock);
        if (error == 0) {

                if (f->xfer[0]->nframes == 1) {
                        error = usb_fifo_alloc_buffer(f,
                            f->xfer[0]->max_data_length, 2);
                } else {
                        error = usb_fifo_alloc_buffer(f,
                            f->xfer[0]->max_frame_size,
                            2 * f->xfer[0]->nframes);
                }
                if (error) {
                        usbd_transfer_unsetup(f->xfer, n_setup);
                }
        }
        lockmgr(f->priv_lock, LK_EXCLUSIVE);

        return (error);
}

static int
ugen_open(struct usb_fifo *f, int fflags)
{
        struct usb_endpoint *ep = usb_fifo_softc(f);
        struct usb_endpoint_descriptor *ed = ep->edesc;
        uint8_t type;

        DPRINTFN(6, "flag=0x%x\n", fflags);

        lockmgr(f->priv_lock, LK_EXCLUSIVE);
        switch (usbd_get_speed(f->udev)) {
        case USB_SPEED_LOW:
        case USB_SPEED_FULL:
                f->nframes = UGEN_HW_FRAMES;
                f->bufsize = UGEN_BULK_FS_BUFFER_SIZE;
                break;
        default:
                f->nframes = UGEN_HW_FRAMES * 8;
                f->bufsize = UGEN_BULK_HS_BUFFER_SIZE;
                break;
        }

        type = ed->bmAttributes & UE_XFERTYPE;
        if (type == UE_INTERRUPT) {
                f->bufsize = 0;         /* use "wMaxPacketSize" */
        }
        f->timeout = USB_NO_TIMEOUT;
        f->flag_short = 0;
        f->fifo_zlp = 0;
        lockmgr(f->priv_lock, LK_RELEASE);

        return (0);
}

static void
ugen_close(struct usb_fifo *f, int fflags)
{
        DPRINTFN(6, "flag=0x%x\n", fflags);

        /* cleanup */

        lockmgr(f->priv_lock, LK_EXCLUSIVE);
        usbd_transfer_stop(f->xfer[0]);
        usbd_transfer_stop(f->xfer[1]);
        lockmgr(f->priv_lock, LK_RELEASE);

        usbd_transfer_unsetup(f->xfer, 2);
        usb_fifo_free_buffer(f);

        if (ugen_fs_uninit(f)) {
                /* ignore any errors - we are closing */
                DPRINTFN(6, "no FIFOs\n");
        }
}

static int
ugen_open_pipe_write(struct usb_fifo *f)
{
        struct usb_config usb_config[2];
        struct usb_endpoint *ep = usb_fifo_softc(f);
        struct usb_endpoint_descriptor *ed = ep->edesc;

        KKASSERT(lockowned(f->priv_lock));

        if (f->xfer[0] || f->xfer[1]) {
                /* transfers are already opened */
                return (0);
        }
        memset(usb_config, 0, sizeof(usb_config));

        usb_config[1].type = UE_CONTROL;
        usb_config[1].endpoint = 0;
        usb_config[1].direction = UE_DIR_ANY;
        usb_config[1].timeout = 1000;   /* 1 second */
        usb_config[1].interval = 50;/* 50 milliseconds */
        usb_config[1].bufsize = sizeof(struct usb_device_request);
        usb_config[1].callback = &ugen_write_clear_stall_callback;
        usb_config[1].usb_mode = USB_MODE_HOST;

        usb_config[0].type = ed->bmAttributes & UE_XFERTYPE;
        usb_config[0].endpoint = ed->bEndpointAddress & UE_ADDR;
        usb_config[0].stream_id = 0;    /* XXX support more stream ID's */
        usb_config[0].direction = UE_DIR_TX;
        usb_config[0].interval = USB_DEFAULT_INTERVAL;
        usb_config[0].flags.proxy_buffer = 1;
        usb_config[0].usb_mode = USB_MODE_DUAL; /* both modes */

        switch (ed->bmAttributes & UE_XFERTYPE) {
        case UE_INTERRUPT:
        case UE_BULK:
                if (f->flag_short) {
                        usb_config[0].flags.force_short_xfer = 1;
                }
                usb_config[0].callback = &ugen_ctrl_write_callback;
                usb_config[0].timeout = f->timeout;
                usb_config[0].frames = 1;
                usb_config[0].bufsize = f->bufsize;
                if (ugen_transfer_setup(f, usb_config, 2)) {
                        return (EIO);
                }
                /* first transfer does not clear stall */
                f->flag_stall = 0;
                break;

        case UE_ISOCHRONOUS:
                usb_config[0].flags.short_xfer_ok = 1;
                usb_config[0].bufsize = 0;      /* use default */
                usb_config[0].frames = f->nframes;
                usb_config[0].callback = &ugen_isoc_write_callback;
                usb_config[0].timeout = 0;

                /* clone configuration */
                usb_config[1] = usb_config[0];

                if (ugen_transfer_setup(f, usb_config, 2)) {
                        return (EIO);
                }
                break;
        default:
                return (EINVAL);
        }
        return (0);
}

static int
ugen_open_pipe_read(struct usb_fifo *f)
{
        struct usb_config usb_config[2];
        struct usb_endpoint *ep = usb_fifo_softc(f);
        struct usb_endpoint_descriptor *ed = ep->edesc;

        KKASSERT(lockowned(f->priv_lock));

        if (f->xfer[0] || f->xfer[1]) {
                /* transfers are already opened */
                return (0);
        }
        memset(usb_config, 0, sizeof(usb_config));

        usb_config[1].type = UE_CONTROL;
        usb_config[1].endpoint = 0;
        usb_config[1].direction = UE_DIR_ANY;
        usb_config[1].timeout = 1000;   /* 1 second */
        usb_config[1].interval = 50;/* 50 milliseconds */
        usb_config[1].bufsize = sizeof(struct usb_device_request);
        usb_config[1].callback = &ugen_read_clear_stall_callback;
        usb_config[1].usb_mode = USB_MODE_HOST;

        usb_config[0].type = ed->bmAttributes & UE_XFERTYPE;
        usb_config[0].endpoint = ed->bEndpointAddress & UE_ADDR;
        usb_config[0].stream_id = 0;    /* XXX support more stream ID's */
        usb_config[0].direction = UE_DIR_RX;
        usb_config[0].interval = USB_DEFAULT_INTERVAL;
        usb_config[0].flags.proxy_buffer = 1;
        usb_config[0].usb_mode = USB_MODE_DUAL; /* both modes */

        switch (ed->bmAttributes & UE_XFERTYPE) {
        case UE_INTERRUPT:
        case UE_BULK:
                if (f->flag_short) {
                        usb_config[0].flags.short_xfer_ok = 1;
                }
                usb_config[0].timeout = f->timeout;
                usb_config[0].frames = 1;
                usb_config[0].callback = &ugen_ctrl_read_callback;
                usb_config[0].bufsize = f->bufsize;

                if (ugen_transfer_setup(f, usb_config, 2)) {
                        return (EIO);
                }
                /* first transfer does not clear stall */
                f->flag_stall = 0;
                break;

        case UE_ISOCHRONOUS:
                usb_config[0].flags.short_xfer_ok = 1;
                usb_config[0].bufsize = 0;      /* use default */
                usb_config[0].frames = f->nframes;
                usb_config[0].callback = &ugen_isoc_read_callback;
                usb_config[0].timeout = 0;

                /* clone configuration */
                usb_config[1] = usb_config[0];

                if (ugen_transfer_setup(f, usb_config, 2)) {
                        return (EIO);
                }
                break;

        default:
                return (EINVAL);
        }
        return (0);
}

static void
ugen_start_read(struct usb_fifo *f)
{
        /* check that pipes are open */
        if (ugen_open_pipe_read(f)) {
                /* signal error */
                usb_fifo_put_data_error(f);
        }
        /* start transfers */
        usbd_transfer_start(f->xfer[0]);
        usbd_transfer_start(f->xfer[1]);
}

static void
ugen_start_write(struct usb_fifo *f)
{
        /* check that pipes are open */
        if (ugen_open_pipe_write(f)) {
                /* signal error */
                usb_fifo_get_data_error(f);
        }
        /* start transfers */
        usbd_transfer_start(f->xfer[0]);
        usbd_transfer_start(f->xfer[1]);
}

static void
ugen_stop_io(struct usb_fifo *f)
{
        /* stop transfers */
        usbd_transfer_stop(f->xfer[0]);
        usbd_transfer_stop(f->xfer[1]);
}

static void
ugen_ctrl_read_callback(struct usb_xfer *xfer, usb_error_t error)
{
        struct usb_fifo *f = usbd_xfer_softc(xfer);
        struct usb_mbuf *m;

        DPRINTFN(4, "actlen=%u, aframes=%u\n", xfer->actlen, xfer->aframes);

        switch (USB_GET_STATE(xfer)) {
        case USB_ST_TRANSFERRED:
                if (xfer->actlen == 0) {
                        if (f->fifo_zlp != 4) {
                                f->fifo_zlp++;
                        } else {
                                /*
                                 * Throttle a little bit we have multiple ZLPs
                                 * in a row!
                                 */
                                xfer->interval = 64;    /* ms */
                        }
                } else {
                        /* clear throttle */
                        xfer->interval = 0;
                        f->fifo_zlp = 0;
                }
                usb_fifo_put_data(f, xfer->frbuffers, 0,
                    xfer->actlen, 1);

        case USB_ST_SETUP:
                if (f->flag_stall) {
                        usbd_transfer_start(f->xfer[1]);
                        break;
                }
                USB_IF_POLL(&f->free_q, m);
                if (m) {
                        usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
                        usbd_transfer_submit(xfer);
                }
                break;

        default:                        /* Error */
                if (xfer->error != USB_ERR_CANCELLED) {
                        /* send a zero length packet to userland */
                        usb_fifo_put_data(f, xfer->frbuffers, 0, 0, 1);
                        f->flag_stall = 1;
                        f->fifo_zlp = 0;
                        usbd_transfer_start(f->xfer[1]);
                }
                break;
        }
}

static void
ugen_ctrl_write_callback(struct usb_xfer *xfer, usb_error_t error)
{
        struct usb_fifo *f = usbd_xfer_softc(xfer);
        usb_frlength_t actlen;

        DPRINTFN(4, "actlen=%u, aframes=%u\n", xfer->actlen, xfer->aframes);

        switch (USB_GET_STATE(xfer)) {
        case USB_ST_SETUP:
        case USB_ST_TRANSFERRED:
                /*
                 * If writing is in stall, just jump to clear stall
                 * callback and solve the situation.
                 */
                if (f->flag_stall) {
                        usbd_transfer_start(f->xfer[1]);
                        break;
                }
                /*
                 * Write data, setup and perform hardware transfer.
                 */
                if (usb_fifo_get_data(f, xfer->frbuffers, 0,
                    xfer->max_data_length, &actlen, 0)) {
                        usbd_xfer_set_frame_len(xfer, 0, actlen);
                        usbd_transfer_submit(xfer);
                }
                break;

        default:                        /* Error */
                if (xfer->error != USB_ERR_CANCELLED) {
                        f->flag_stall = 1;
                        usbd_transfer_start(f->xfer[1]);
                }
                break;
        }
}

static void
ugen_read_clear_stall_callback(struct usb_xfer *xfer, usb_error_t error)
{
        struct usb_fifo *f = usbd_xfer_softc(xfer);
        struct usb_xfer *xfer_other = f->xfer[0];

        if (f->flag_stall == 0) {
                /* nothing to do */
                return;
        }
        if (usbd_clear_stall_callback(xfer, xfer_other)) {
                DPRINTFN(5, "f=%p: stall cleared\n", f);
                f->flag_stall = 0;
                usbd_transfer_start(xfer_other);
        }
}

static void
ugen_write_clear_stall_callback(struct usb_xfer *xfer, usb_error_t error)
{
        struct usb_fifo *f = usbd_xfer_softc(xfer);
        struct usb_xfer *xfer_other = f->xfer[0];

        if (f->flag_stall == 0) {
                /* nothing to do */
                return;
        }
        if (usbd_clear_stall_callback(xfer, xfer_other)) {
                DPRINTFN(5, "f=%p: stall cleared\n", f);
                f->flag_stall = 0;
                usbd_transfer_start(xfer_other);
        }
}

static void
ugen_isoc_read_callback(struct usb_xfer *xfer, usb_error_t error)
{
        struct usb_fifo *f = usbd_xfer_softc(xfer);
        usb_frlength_t offset;
        usb_frcount_t n;

        DPRINTFN(4, "actlen=%u, aframes=%u\n", xfer->actlen, xfer->aframes);

        switch (USB_GET_STATE(xfer)) {
        case USB_ST_TRANSFERRED:

                DPRINTFN(6, "actlen=%d\n", xfer->actlen);

                offset = 0;

                for (n = 0; n != xfer->aframes; n++) {
                        usb_fifo_put_data(f, xfer->frbuffers, offset,
                            xfer->frlengths[n], 1);
                        offset += xfer->max_frame_size;
                }

        case USB_ST_SETUP:
tr_setup:
                for (n = 0; n != xfer->nframes; n++) {
                        /* setup size for next transfer */
                        usbd_xfer_set_frame_len(xfer, n, xfer->max_frame_size);
                }
                usbd_transfer_submit(xfer);
                break;

        default:                        /* Error */
                if (xfer->error == USB_ERR_CANCELLED) {
                        break;
                }
                goto tr_setup;
        }
}

static void
ugen_isoc_write_callback(struct usb_xfer *xfer, usb_error_t error)
{
        struct usb_fifo *f = usbd_xfer_softc(xfer);
        usb_frlength_t actlen;
        usb_frlength_t offset;
        usb_frcount_t n;

        DPRINTFN(4, "actlen=%u, aframes=%u\n", xfer->actlen, xfer->aframes);

        switch (USB_GET_STATE(xfer)) {
        case USB_ST_TRANSFERRED:
        case USB_ST_SETUP:
tr_setup:
                offset = 0;
                for (n = 0; n != xfer->nframes; n++) {
                        if (usb_fifo_get_data(f, xfer->frbuffers, offset,
                            xfer->max_frame_size, &actlen, 1)) {
                                usbd_xfer_set_frame_len(xfer, n, actlen);
                                offset += actlen;
                        } else {
                                break;
                        }
                }

                for (; n != xfer->nframes; n++) {
                        /* fill in zero frames */
                        usbd_xfer_set_frame_len(xfer, n, 0);
                }
                usbd_transfer_submit(xfer);
                break;

        default:                        /* Error */
                if (xfer->error == USB_ERR_CANCELLED) {
                        break;
                }
                goto tr_setup;
        }
}

static int
ugen_set_config(struct usb_fifo *f, uint8_t index)
{
        DPRINTFN(2, "index %u\n", index);

        if (f->udev->flags.usb_mode != USB_MODE_HOST) {
                /* not possible in device side mode */
                return (ENOTTY);
        }

        /* make sure all FIFO's are gone */
        /* else there can be a deadlock */
        if (ugen_fs_uninit(f)) {
                /* ignore any errors */
                DPRINTFN(6, "no FIFOs\n");
        }

        if (usbd_start_set_config(f->udev, index) != 0)
                return (EIO);

        return (0);
}

static int
ugen_set_interface(struct usb_fifo *f,
    uint8_t iface_index, uint8_t alt_index)
{
        DPRINTFN(2, "%u, %u\n", iface_index, alt_index);

        if (f->udev->flags.usb_mode != USB_MODE_HOST) {
                /* not possible in device side mode */
                return (ENOTTY);
        }
        /* make sure all FIFO's are gone */
        /* else there can be a deadlock */
        if (ugen_fs_uninit(f)) {
                /* ignore any errors */
                DPRINTFN(6, "no FIFOs\n");
        }
        /* change setting - will free generic FIFOs, if any */
        if (usbd_set_alt_interface_index(f->udev, iface_index, alt_index)) {
                return (EIO);
        }
        /* probe and attach */
        if (usb_probe_and_attach(f->udev, iface_index)) {
                return (EIO);
        }
        return (0);
}

/*------------------------------------------------------------------------*
 *      ugen_get_cdesc
 *
 * This function will retrieve the complete configuration descriptor
 * at the given index.
 *------------------------------------------------------------------------*/
static int
ugen_get_cdesc(struct usb_fifo *f, struct usb_gen_descriptor *ugd)
{
        struct usb_config_descriptor *cdesc;
        struct usb_device *udev = f->udev;
        int error;
        uint16_t len;
        uint8_t free_data;

        DPRINTFN(6, "\n");

        if (ugd->ugd_data == NULL) {
                /* userland pointer should not be zero */
                return (EINVAL);
        }
        if ((ugd->ugd_config_index == USB_UNCONFIG_INDEX) ||
            (ugd->ugd_config_index == udev->curr_config_index)) {
                cdesc = usbd_get_config_descriptor(udev);
                if (cdesc == NULL) {
                        return (ENXIO);
                }
                free_data = 0;

        } else {
#if (USB_HAVE_FIXED_CONFIG == 0)
                if (usbd_req_get_config_desc_full(udev,
                    NULL, &cdesc, ugd->ugd_config_index)) {
                        return (ENXIO);
                }
                free_data = 1;
#else
                /* configuration descriptor data is shared */
                return (EINVAL);
#endif
        }

        len = UGETW(cdesc->wTotalLength);
        if (len > ugd->ugd_maxlen) {
                len = ugd->ugd_maxlen;
        }
        DPRINTFN(6, "len=%u\n", len);

        ugd->ugd_actlen = len;
        ugd->ugd_offset = 0;

        error = copyout(cdesc, ugd->ugd_data, len);

        if (free_data)
                usbd_free_config_desc(udev, cdesc);

        return (error);
}

/*
 * This function is called having the enumeration SX locked which
 * protects the scratch area used.
 */
static int
ugen_get_sdesc(struct usb_fifo *f, struct usb_gen_descriptor *ugd)
{
        void *ptr;
        uint16_t size;
        int error;

        ptr = f->udev->scratch.data;
        size = sizeof(f->udev->scratch.data);

        if (usbd_req_get_string_desc(f->udev, NULL, ptr,
            size, ugd->ugd_lang_id, ugd->ugd_string_index)) {
                error = EINVAL;
        } else {

                if (size > ((uint8_t *)ptr)[0]) {
                        size = ((uint8_t *)ptr)[0];
                }
                if (size > ugd->ugd_maxlen) {
                        size = ugd->ugd_maxlen;
                }
                ugd->ugd_actlen = size;
                ugd->ugd_offset = 0;

                error = copyout(ptr, ugd->ugd_data, size);
        }
        return (error);
}

/*------------------------------------------------------------------------*
 *      ugen_get_iface_driver
 *
 * This function generates an USB interface description for userland.
 *
 * Returns:
 *    0: Success
 * Else: Failure
 *------------------------------------------------------------------------*/
static int
ugen_get_iface_driver(struct usb_fifo *f, struct usb_gen_descriptor *ugd)
{
        struct usb_device *udev = f->udev;
        struct usb_interface *iface;
        const char *ptr;
        const char *desc;
        unsigned int len;
        unsigned int maxlen;
        char buf[128];
        int error;

        DPRINTFN(6, "\n");

        if ((ugd->ugd_data == NULL) || (ugd->ugd_maxlen == 0)) {
                /* userland pointer should not be zero */
                return (EINVAL);
        }

        iface = usbd_get_iface(udev, ugd->ugd_iface_index);
        if ((iface == NULL) || (iface->idesc == NULL)) {
                /* invalid interface index */
                return (EINVAL);
        }

        /* read out device nameunit string, if any */
        if ((iface->subdev != NULL) &&
            device_is_attached(iface->subdev) &&
            (ptr = device_get_nameunit(iface->subdev)) &&
            (desc = device_get_desc(iface->subdev))) {

                /* print description */
                ksnprintf(buf, sizeof(buf), "%s: <%s>", ptr, desc);

                /* range checks */
                maxlen = ugd->ugd_maxlen - 1;
                len = strlen(buf);
                if (len > maxlen)
                        len = maxlen;

                /* update actual length, including terminating zero */
                ugd->ugd_actlen = len + 1;

                /* copy out interface description */
                error = copyout(buf, ugd->ugd_data, ugd->ugd_actlen);
        } else {
                /* zero length string is default */
                error = copyout("", ugd->ugd_data, 1);
        }
        return (error);
}

/*------------------------------------------------------------------------*
 *      usb_gen_fill_deviceinfo
 *
 * This function dumps information about an USB device to the
 * structure pointed to by the "di" argument.
 *
 * Returns:
 *    0: Success
 * Else: Failure
 *------------------------------------------------------------------------*/
static int
usb_gen_fill_deviceinfo(struct usb_fifo *f, struct usb_device_info *di)
{
        struct usb_device *udev;
        struct usb_device *hub;

        udev = f->udev;

        bzero(di, sizeof(di[0]));

        di->udi_bus = device_get_unit(udev->bus->bdev);
        di->udi_addr = udev->address;
        di->udi_index = udev->device_index;
        strlcpy(di->udi_serial, usb_get_serial(udev), sizeof(di->udi_serial));
        strlcpy(di->udi_vendor, usb_get_manufacturer(udev), sizeof(di->udi_vendor));
        strlcpy(di->udi_product, usb_get_product(udev), sizeof(di->udi_product));
        usb_printbcd(di->udi_release, sizeof(di->udi_release),
            UGETW(udev->ddesc.bcdDevice));
        di->udi_vendorNo = UGETW(udev->ddesc.idVendor);
        di->udi_productNo = UGETW(udev->ddesc.idProduct);
        di->udi_releaseNo = UGETW(udev->ddesc.bcdDevice);
        di->udi_class = udev->ddesc.bDeviceClass;
        di->udi_subclass = udev->ddesc.bDeviceSubClass;
        di->udi_protocol = udev->ddesc.bDeviceProtocol;
        di->udi_config_no = udev->curr_config_no;
        di->udi_config_index = udev->curr_config_index;
        di->udi_power = udev->flags.self_powered ? 0 : udev->power;
        di->udi_speed = udev->speed;
        di->udi_mode = udev->flags.usb_mode;
        di->udi_power_mode = udev->power_mode;
        di->udi_suspended = udev->flags.peer_suspended;

        hub = udev->parent_hub;
        if (hub) {
                di->udi_hubaddr = hub->address;
                di->udi_hubindex = hub->device_index;
                di->udi_hubport = udev->port_no;
        }
        return (0);
}

/*------------------------------------------------------------------------*
 *      ugen_check_request
 *
 * Return values:
 * 0: Access allowed
 * Else: No access
 *------------------------------------------------------------------------*/
static int
ugen_check_request(struct usb_device *udev, struct usb_device_request *req)
{
        struct usb_endpoint *ep;
        int error;

        /*
         * Avoid requests that would damage the bus integrity:
         */
        if (((req->bmRequestType == UT_WRITE_DEVICE) &&
            (req->bRequest == UR_SET_ADDRESS)) ||
            ((req->bmRequestType == UT_WRITE_DEVICE) &&
            (req->bRequest == UR_SET_CONFIG)) ||
            ((req->bmRequestType == UT_WRITE_INTERFACE) &&
            (req->bRequest == UR_SET_INTERFACE)))
        {
                /*
                 * These requests can be useful for testing USB drivers.
                 */
                error = caps_priv_check_self(SYSCAP_NODRIVER);
                if (error)
                        return (error);
        }
        /*
         * Special case - handle clearing of stall
         */
        if (req->bmRequestType == UT_WRITE_ENDPOINT) {

                ep = usbd_get_ep_by_addr(udev, req->wIndex[0]);
                if (ep == NULL) {
                        return (EINVAL);
                }
                if ((req->bRequest == UR_CLEAR_FEATURE) &&
                    (UGETW(req->wValue) == UF_ENDPOINT_HALT)) {
                        usbd_clear_data_toggle(udev, ep);
                }
        }
        /* TODO: add more checks to verify the interface index */

        return (0);
}

int
ugen_do_request(struct usb_fifo *f, struct usb_ctl_request *ur)
{
        int error;
        uint16_t len;
        uint16_t actlen;

        if (ugen_check_request(f->udev, &ur->ucr_request)) {
                return (EPERM);
        }
        len = UGETW(ur->ucr_request.wLength);

        /* check if "ucr_data" is valid */
        if (len != 0) {
                if (ur->ucr_data == NULL) {
                        return (EFAULT);
                }
        }
        /* do the USB request */
        error = usbd_do_request_flags
            (f->udev, NULL, &ur->ucr_request, ur->ucr_data,
            (ur->ucr_flags & USB_SHORT_XFER_OK) |
            USB_USER_DATA_PTR, &actlen,
            USB_DEFAULT_TIMEOUT);

        ur->ucr_actlen = actlen;

        if (error) {
                error = EIO;
        }
        return (error);
}

/*------------------------------------------------------------------------
 *      ugen_re_enumerate
 *------------------------------------------------------------------------*/
static int
ugen_re_enumerate(struct usb_fifo *f)
{
        struct usb_device *udev = f->udev;
        int error;

        /*
         * This request can be useful for testing USB drivers:
         */
        error = caps_priv_check_self(SYSCAP_NODRIVER);
        if (error)
                return (error);

        if (udev->flags.usb_mode != USB_MODE_HOST) {
                /* not possible in device side mode */
                DPRINTFN(6, "device mode\n");
                return (ENOTTY);
        }
        /* make sure all FIFO's are gone */
        /* else there can be a deadlock */
        if (ugen_fs_uninit(f)) {
                /* ignore any errors */
                DPRINTFN(6, "no FIFOs\n");
        }
        /* start re-enumeration of device */
        usbd_start_re_enumerate(udev);
        return (0);
}

int
ugen_fs_uninit(struct usb_fifo *f)
{
        if (f->fs_xfer == NULL) {
                return (EINVAL);
        }
        usbd_transfer_unsetup(f->fs_xfer, f->fs_ep_max);
        kfree(f->fs_xfer, M_USB);
        f->fs_xfer = NULL;
        f->fs_ep_max = 0;
        f->fs_ep_ptr = NULL;
        f->flag_iscomplete = 0;
        usb_fifo_free_buffer(f);
        return (0);
}

static uint8_t
ugen_fs_get_complete(struct usb_fifo *f, uint8_t *pindex)
{
        struct usb_mbuf *m;

        USB_IF_DEQUEUE(&f->used_q, m);

        if (m) {
                *pindex = *((uint8_t *)(m->cur_data_ptr));

                USB_IF_ENQUEUE(&f->free_q, m);

                return (0);             /* success */
        } else {

                *pindex = 0;            /* fix compiler warning */

                f->flag_iscomplete = 0;
        }
        return (1);                     /* failure */
}

static void
ugen_fs_set_complete(struct usb_fifo *f, uint8_t index)
{
        struct usb_mbuf *m;

        USB_IF_DEQUEUE(&f->free_q, m);

        if (m == NULL) {
                /* can happen during close */
                DPRINTF("out of buffers\n");
                return;
        }
        USB_MBUF_RESET(m);

        *((uint8_t *)(m->cur_data_ptr)) = index;

        USB_IF_ENQUEUE(&f->used_q, m);

        f->flag_iscomplete = 1;

        usb_fifo_wakeup(f);
}

static int
ugen_fs_copy_in(struct usb_fifo *f, uint8_t ep_index)
{
        struct usb_device_request *req;
        struct usb_xfer *xfer;
        struct usb_fs_endpoint fs_ep;
        void *uaddr;                    /* userland pointer */
        void *kaddr;
        usb_frlength_t offset;
        usb_frlength_t rem;
        usb_frcount_t n;
        uint32_t length;
        int error;
        uint8_t isread;

        if (ep_index >= f->fs_ep_max) {
                return (EINVAL);
        }
        xfer = f->fs_xfer[ep_index];
        if (xfer == NULL) {
                return (EINVAL);
        }
        lockmgr(f->priv_lock, LK_EXCLUSIVE);
        if (usbd_transfer_pending(xfer)) {
                lockmgr(f->priv_lock, LK_RELEASE);
                return (EBUSY);         /* should not happen */
        }
        lockmgr(f->priv_lock, LK_RELEASE);

        error = copyin(f->fs_ep_ptr +
            ep_index, &fs_ep, sizeof(fs_ep));
        if (error) {
                return (error);
        }
        /* security checks */

        if (fs_ep.nFrames > xfer->max_frame_count) {
                xfer->error = USB_ERR_INVAL;
                goto complete;
        }
        if (fs_ep.nFrames == 0) {
                xfer->error = USB_ERR_INVAL;
                goto complete;
        }
        error = copyin(fs_ep.ppBuffer,
            &uaddr, sizeof(uaddr));
        if (error) {
                return (error);
        }
        /* reset first frame */
        usbd_xfer_set_frame_offset(xfer, 0, 0);

        if (xfer->flags_int.control_xfr) {

                req = xfer->frbuffers[0].buffer;

                error = copyin(fs_ep.pLength,
                    &length, sizeof(length));
                if (error) {
                        return (error);
                }
                if (length != sizeof(*req)) {
                        xfer->error = USB_ERR_INVAL;
                        goto complete;
                }
                if (length != 0) {
                        error = copyin(uaddr, req, length);
                        if (error) {
                                return (error);
                        }
                }
                if (ugen_check_request(f->udev, req)) {
                        xfer->error = USB_ERR_INVAL;
                        goto complete;
                }
                usbd_xfer_set_frame_len(xfer, 0, length);

                /* Host mode only ! */
                if ((req->bmRequestType &
                    (UT_READ | UT_WRITE)) == UT_READ) {
                        isread = 1;
                } else {
                        isread = 0;
                }
                n = 1;
                offset = sizeof(*req);

        } else {
                /* Device and Host mode */
                if (USB_GET_DATA_ISREAD(xfer)) {
                        isread = 1;
                } else {
                        isread = 0;
                }
                n = 0;
                offset = 0;
        }

        rem = usbd_xfer_max_len(xfer);
        xfer->nframes = fs_ep.nFrames;
        xfer->timeout = fs_ep.timeout;
        if (xfer->timeout > 65535) {
                xfer->timeout = 65535;
        }
        if (fs_ep.flags & USB_FS_FLAG_SINGLE_SHORT_OK)
                xfer->flags.short_xfer_ok = 1;
        else
                xfer->flags.short_xfer_ok = 0;

        if (fs_ep.flags & USB_FS_FLAG_MULTI_SHORT_OK)
                xfer->flags.short_frames_ok = 1;
        else
                xfer->flags.short_frames_ok = 0;

        if (fs_ep.flags & USB_FS_FLAG_FORCE_SHORT)
                xfer->flags.force_short_xfer = 1;
        else
                xfer->flags.force_short_xfer = 0;

        if (fs_ep.flags & USB_FS_FLAG_CLEAR_STALL)
                usbd_xfer_set_stall(xfer);
        else
                xfer->flags.stall_pipe = 0;

        for (; n != xfer->nframes; n++) {

                error = copyin(fs_ep.pLength + n,
                    &length, sizeof(length));
                if (error) {
                        break;
                }
                usbd_xfer_set_frame_len(xfer, n, length);

                if (length > rem) {
                        xfer->error = USB_ERR_INVAL;
                        goto complete;
                }
                rem -= length;

                if (!isread) {

                        /* we need to know the source buffer */
                        error = copyin(fs_ep.ppBuffer + n,
                            &uaddr, sizeof(uaddr));
                        if (error) {
                                break;
                        }
                        if (xfer->flags_int.isochronous_xfr) {
                                /* get kernel buffer address */
                                kaddr = xfer->frbuffers[0].buffer;
                                kaddr = USB_ADD_BYTES(kaddr, offset);
                        } else {
                                /* set current frame offset */
                                usbd_xfer_set_frame_offset(xfer, offset, n);

                                /* get kernel buffer address */
                                kaddr = xfer->frbuffers[n].buffer;
                        }

                        /* move data */
                        error = copyin(uaddr, kaddr, length);
                        if (error) {
                                break;
                        }
                }
                offset += length;
        }
        return (error);

complete:
        lockmgr(f->priv_lock, LK_EXCLUSIVE);
        ugen_fs_set_complete(f, ep_index);
        lockmgr(f->priv_lock, LK_RELEASE);
        return (0);
}

static int
ugen_fs_copy_out(struct usb_fifo *f, uint8_t ep_index)
{
        struct usb_device_request *req;
        struct usb_xfer *xfer;
        struct usb_fs_endpoint fs_ep;
        struct usb_fs_endpoint *fs_ep_uptr;     /* userland ptr */
        void *uaddr;                    /* userland ptr */
        void *kaddr;
        usb_frlength_t offset;
        usb_frlength_t rem;
        usb_frcount_t n;
        uint32_t length;
        uint32_t temp;
        int error;
        uint8_t isread;

        if (ep_index >= f->fs_ep_max)
                return (EINVAL);

        xfer = f->fs_xfer[ep_index];
        if (xfer == NULL)
                return (EINVAL);

        lockmgr(f->priv_lock, LK_EXCLUSIVE);
        if (usbd_transfer_pending(xfer)) {
                lockmgr(f->priv_lock, LK_RELEASE);
                return (EBUSY);         /* should not happen */
        }
        lockmgr(f->priv_lock, LK_RELEASE);

        fs_ep_uptr = f->fs_ep_ptr + ep_index;
        error = copyin(fs_ep_uptr, &fs_ep, sizeof(fs_ep));
        if (error) {
                return (error);
        }
        fs_ep.status = xfer->error;
        fs_ep.aFrames = xfer->aframes;
        fs_ep.isoc_time_complete = xfer->isoc_time_complete;
        if (xfer->error) {
                goto complete;
        }
        if (xfer->flags_int.control_xfr) {
                req = xfer->frbuffers[0].buffer;

                /* Host mode only ! */
                if ((req->bmRequestType & (UT_READ | UT_WRITE)) == UT_READ) {
                        isread = 1;
                } else {
                        isread = 0;
                }
                if (xfer->nframes == 0)
                        n = 0;          /* should never happen */
                else
                        n = 1;
        } else {
                /* Device and Host mode */
                if (USB_GET_DATA_ISREAD(xfer)) {
                        isread = 1;
                } else {
                        isread = 0;
                }
                n = 0;
        }

        /* Update lengths and copy out data */

        rem = usbd_xfer_max_len(xfer);
        offset = 0;

        for (; n != xfer->nframes; n++) {

                /* get initial length into "temp" */
                error = copyin(fs_ep.pLength + n,
                    &temp, sizeof(temp));
                if (error) {
                        return (error);
                }
                if (temp > rem) {
                        /* the userland length has been corrupted */
                        DPRINTF("corrupt userland length "
                            "%u > %u\n", temp, rem);
                        fs_ep.status = USB_ERR_INVAL;
                        goto complete;
                }
                rem -= temp;

                /* get actual transfer length */
                length = xfer->frlengths[n];
                if (length > temp) {
                        /* data overflow */
                        fs_ep.status = USB_ERR_INVAL;
                        DPRINTF("data overflow %u > %u\n",
                            length, temp);
                        goto complete;
                }
                if (isread) {

                        /* we need to know the destination buffer */
                        error = copyin(fs_ep.ppBuffer + n,
                            &uaddr, sizeof(uaddr));
                        if (error) {
                                return (error);
                        }
                        if (xfer->flags_int.isochronous_xfr) {
                                /* only one frame buffer */
                                kaddr = USB_ADD_BYTES(
                                    xfer->frbuffers[0].buffer, offset);
                        } else {
                                /* multiple frame buffers */
                                kaddr = xfer->frbuffers[n].buffer;
                        }

                        /* move data */
                        error = copyout(kaddr, uaddr, length);
                        if (error) {
                                return (error);
                        }
                }
                /*
                 * Update offset according to initial length, which is
                 * needed by isochronous transfers!
                 */
                offset += temp;

                /* update length */
                error = copyout(&length,
                    fs_ep.pLength + n, sizeof(length));
                if (error) {
                        return (error);
                }
        }

complete:
        /* update "aFrames" */
        error = copyout(&fs_ep.aFrames, &fs_ep_uptr->aFrames,
            sizeof(fs_ep.aFrames));
        if (error)
                goto done;

        /* update "isoc_time_complete" */
        error = copyout(&fs_ep.isoc_time_complete,
            &fs_ep_uptr->isoc_time_complete,
            sizeof(fs_ep.isoc_time_complete));
        if (error)
                goto done;
        /* update "status" */
        error = copyout(&fs_ep.status, &fs_ep_uptr->status,
            sizeof(fs_ep.status));
done:
        return (error);
}

static uint8_t
ugen_fifo_in_use(struct usb_fifo *f, int fflags)
{
        struct usb_fifo *f_rx;
        struct usb_fifo *f_tx;

        f_rx = f->udev->fifo[(f->fifo_index & ~1) + USB_FIFO_RX];
        f_tx = f->udev->fifo[(f->fifo_index & ~1) + USB_FIFO_TX];

        if ((fflags & FREAD) && f_rx &&
            (f_rx->xfer[0] || f_rx->xfer[1])) {
                return (1);             /* RX FIFO in use */
        }
        if ((fflags & FWRITE) && f_tx &&
            (f_tx->xfer[0] || f_tx->xfer[1])) {
                return (1);             /* TX FIFO in use */
        }
        return (0);                     /* not in use */
}

static int
ugen_ioctl(struct usb_fifo *f, u_long cmd, void *addr, int fflags)
{
        struct usb_config usb_config[1];
        struct usb_device_request req;
        union {
                struct usb_fs_complete *pcomp;
                struct usb_fs_start *pstart;
                struct usb_fs_stop *pstop;
                struct usb_fs_open *popen;
                struct usb_fs_open_stream *popen_stream;
                struct usb_fs_close *pclose;
                struct usb_fs_clear_stall_sync *pstall;
                void   *addr;
        }     u;
        struct usb_endpoint *ep;
        struct usb_endpoint_descriptor *ed;
        struct usb_xfer *xfer;
        int error = 0;
        uint8_t iface_index;
        uint8_t isread;
        uint8_t ep_index;
        uint8_t pre_scale;

        u.addr = addr;

        DPRINTFN(6, "cmd=0x%08lx\n", cmd);

        switch (cmd) {
        case USB_FS_COMPLETE:
                lockmgr(f->priv_lock, LK_EXCLUSIVE);
                error = ugen_fs_get_complete(f, &ep_index);
                lockmgr(f->priv_lock, LK_RELEASE);

                if (error) {
                        error = EBUSY;
                        break;
                }
                u.pcomp->ep_index = ep_index;
                error = ugen_fs_copy_out(f, u.pcomp->ep_index);
                break;

        case USB_FS_START:
                error = ugen_fs_copy_in(f, u.pstart->ep_index);
                if (error)
                        break;
                lockmgr(f->priv_lock, LK_EXCLUSIVE);
                xfer = f->fs_xfer[u.pstart->ep_index];
                usbd_transfer_start(xfer);
                lockmgr(f->priv_lock, LK_RELEASE);
                break;

        case USB_FS_STOP:
                if (u.pstop->ep_index >= f->fs_ep_max) {
                        error = EINVAL;
                        break;
                }
                lockmgr(f->priv_lock, LK_EXCLUSIVE);
                xfer = f->fs_xfer[u.pstart->ep_index];
                if (usbd_transfer_pending(xfer)) {
                        usbd_transfer_stop(xfer);
                        /*
                         * Check if the USB transfer was stopped
                         * before it was even started. Else a cancel
                         * callback will be pending.
                         */
                        if (!xfer->flags_int.transferring) {
                                ugen_fs_set_complete(xfer->priv_sc,
                                    USB_P2U(xfer->priv_fifo));
                        }
                }
                lockmgr(f->priv_lock, LK_RELEASE);
                break;

        case USB_FS_OPEN:
        case USB_FS_OPEN_STREAM:
                if (u.popen->ep_index >= f->fs_ep_max) {
                        error = EINVAL;
                        break;
                }
                if (f->fs_xfer[u.popen->ep_index] != NULL) {
                        error = EBUSY;
                        break;
                }
                if (u.popen->max_bufsize > USB_FS_MAX_BUFSIZE) {
                        u.popen->max_bufsize = USB_FS_MAX_BUFSIZE;
                }
                if (u.popen->max_frames & USB_FS_MAX_FRAMES_PRE_SCALE) {
                        pre_scale = 1;
                        u.popen->max_frames &= ~USB_FS_MAX_FRAMES_PRE_SCALE;
                } else {
                        pre_scale = 0;
                }
                if (u.popen->max_frames > USB_FS_MAX_FRAMES) {
                        u.popen->max_frames = USB_FS_MAX_FRAMES;
                        break;
                }
                if (u.popen->max_frames == 0) {
                        error = EINVAL;
                        break;
                }
                ep = usbd_get_ep_by_addr(f->udev, u.popen->ep_no);
                if (ep == NULL) {
                        error = EINVAL;
                        break;
                }
                ed = ep->edesc;
                if (ed == NULL) {
                        error = ENXIO;
                        break;
                }
                iface_index = ep->iface_index;

                memset(usb_config, 0, sizeof(usb_config));

                usb_config[0].type = ed->bmAttributes & UE_XFERTYPE;
                usb_config[0].endpoint = ed->bEndpointAddress & UE_ADDR;
                usb_config[0].direction = ed->bEndpointAddress & (UE_DIR_OUT | UE_DIR_IN);
                usb_config[0].interval = USB_DEFAULT_INTERVAL;
                usb_config[0].flags.proxy_buffer = 1;
                if (pre_scale != 0)
                        usb_config[0].flags.pre_scale_frames = 1;
                usb_config[0].callback = &ugen_ctrl_fs_callback;
                usb_config[0].timeout = 0;      /* no timeout */
                usb_config[0].frames = u.popen->max_frames;
                usb_config[0].bufsize = u.popen->max_bufsize;
                usb_config[0].usb_mode = USB_MODE_DUAL; /* both modes */
                if (cmd == USB_FS_OPEN_STREAM)
                        usb_config[0].stream_id = u.popen_stream->stream_id;

                if (usb_config[0].type == UE_CONTROL) {
                        if (f->udev->flags.usb_mode != USB_MODE_HOST) {
                                error = EINVAL;
                                break;
                        }
                } else {

                        isread = ((usb_config[0].endpoint &
                            (UE_DIR_IN | UE_DIR_OUT)) == UE_DIR_IN);

                        if (f->udev->flags.usb_mode != USB_MODE_HOST) {
                                isread = !isread;
                        }
                        /* check permissions */
                        if (isread) {
                                if (!(fflags & FREAD)) {
                                        error = EPERM;
                                        break;
                                }
                        } else {
                                if (!(fflags & FWRITE)) {
                                        error = EPERM;
                                        break;
                                }
                        }
                }
                error = usbd_transfer_setup(f->udev, &iface_index,
                    f->fs_xfer + u.popen->ep_index, usb_config, 1,
                    f, f->priv_lock);
                if (error == 0) {
                        /* update maximums */
                        u.popen->max_packet_length =
                            f->fs_xfer[u.popen->ep_index]->max_frame_size;
                        u.popen->max_bufsize =
                            f->fs_xfer[u.popen->ep_index]->max_data_length;
                        /* update number of frames */
                        u.popen->max_frames =
                            f->fs_xfer[u.popen->ep_index]->nframes;
                        /* store index of endpoint */
                        f->fs_xfer[u.popen->ep_index]->priv_fifo =
                            ((uint8_t *)0) + u.popen->ep_index;
                } else {
                        error = ENOMEM;
                }
                break;

        case USB_FS_CLOSE:
                if (u.pclose->ep_index >= f->fs_ep_max) {
                        error = EINVAL;
                        break;
                }
                if (f->fs_xfer[u.pclose->ep_index] == NULL) {
                        error = EINVAL;
                        break;
                }
                usbd_transfer_unsetup(f->fs_xfer + u.pclose->ep_index, 1);
                break;

        case USB_FS_CLEAR_STALL_SYNC:
                if (u.pstall->ep_index >= f->fs_ep_max) {
                        error = EINVAL;
                        break;
                }
                if (f->fs_xfer[u.pstall->ep_index] == NULL) {
                        error = EINVAL;
                        break;
                }
                if (f->udev->flags.usb_mode != USB_MODE_HOST) {
                        error = EINVAL;
                        break;
                }
                lockmgr(f->priv_lock, LK_EXCLUSIVE);
                error = usbd_transfer_pending(f->fs_xfer[u.pstall->ep_index]);
                lockmgr(f->priv_lock, LK_RELEASE);

                if (error) {
                        return (EBUSY);
                }
                ep = f->fs_xfer[u.pstall->ep_index]->endpoint;

                /* setup a clear-stall packet */
                req.bmRequestType = UT_WRITE_ENDPOINT;
                req.bRequest = UR_CLEAR_FEATURE;
                USETW(req.wValue, UF_ENDPOINT_HALT);
                req.wIndex[0] = ep->edesc->bEndpointAddress;
                req.wIndex[1] = 0;
                USETW(req.wLength, 0);

                error = usbd_do_request(f->udev, NULL, &req, NULL);
                if (error == 0) {
                        usbd_clear_data_toggle(f->udev, ep);
                } else {
                        error = ENXIO;
                }
                break;

        default:
                error = ENOIOCTL;
                break;
        }

        DPRINTFN(6, "error=%d\n", error);

        return (error);
}

static int
ugen_set_short_xfer(struct usb_fifo *f, void *addr)
{
        uint8_t t;

        if (*(int *)addr)
                t = 1;
        else
                t = 0;

        if (f->flag_short == t) {
                /* same value like before - accept */
                return (0);
        }
        if (f->xfer[0] || f->xfer[1]) {
                /* cannot change this during transfer */
                return (EBUSY);
        }
        f->flag_short = t;
        return (0);
}

static int
ugen_set_timeout(struct usb_fifo *f, void *addr)
{
        f->timeout = *(int *)addr;
        if (f->timeout > 65535) {
                /* limit user input */
                f->timeout = 65535;
        }
        return (0);
}

static int
ugen_get_frame_size(struct usb_fifo *f, void *addr)
{
        if (f->xfer[0]) {
                *(int *)addr = f->xfer[0]->max_frame_size;
        } else {
                return (EINVAL);
        }
        return (0);
}

static int
ugen_set_buffer_size(struct usb_fifo *f, void *addr)
{
        usb_frlength_t t;

        if (*(int *)addr < 0)
                t = 0;          /* use "wMaxPacketSize" */
        else if (*(int *)addr < (256 * 1024))
                t = *(int *)addr;
        else
                t = 256 * 1024;

        if (f->bufsize == t) {
                /* same value like before - accept */
                return (0);
        }
        if (f->xfer[0] || f->xfer[1]) {
                /* cannot change this during transfer */
                return (EBUSY);
        }
        f->bufsize = t;
        return (0);
}

static int
ugen_get_buffer_size(struct usb_fifo *f, void *addr)
{
        *(int *)addr = f->bufsize;
        return (0);
}

static int
ugen_get_iface_desc(struct usb_fifo *f,
    struct usb_interface_descriptor *idesc)
{
        struct usb_interface *iface;

        iface = usbd_get_iface(f->udev, f->iface_index);
        if (iface && iface->idesc) {
                *idesc = *(iface->idesc);
        } else {
                return (EIO);
        }
        return (0);
}

static int
ugen_get_endpoint_desc(struct usb_fifo *f,
    struct usb_endpoint_descriptor *ed)
{
        struct usb_endpoint *ep;

        ep = usb_fifo_softc(f);

        if (ep && ep->edesc) {
                *ed = *ep->edesc;
        } else {
                return (EINVAL);
        }
        return (0);
}

static int
ugen_set_power_mode(struct usb_fifo *f, int mode)
{
        struct usb_device *udev = f->udev;
        int err;
        uint8_t old_mode;

        if ((udev == NULL) ||
            (udev->parent_hub == NULL)) {
                return (EINVAL);
        }
        err = caps_priv_check_self(SYSCAP_NODRIVER);
        if (err)
                return (err);

        /* get old power mode */
        old_mode = udev->power_mode;

        /* if no change, then just return */
        if (old_mode == mode)
                return (0);

        switch (mode) {
        case USB_POWER_MODE_OFF:
                if (udev->flags.usb_mode == USB_MODE_HOST &&
                    udev->re_enumerate_wait == USB_RE_ENUM_DONE) {
                        udev->re_enumerate_wait = USB_RE_ENUM_PWR_OFF;
                }
                /* set power mode will wake up the explore thread */
                break;

        case USB_POWER_MODE_ON:
        case USB_POWER_MODE_SAVE:
                break;

        case USB_POWER_MODE_RESUME:
#if USB_HAVE_POWERD
                /* let USB-powerd handle resume */
                USB_BUS_LOCK(udev->bus);
                udev->pwr_save.write_refs++;
                udev->pwr_save.last_xfer_time = ticks;
                USB_BUS_UNLOCK(udev->bus);

                /* set new power mode */
                usbd_set_power_mode(udev, USB_POWER_MODE_SAVE);

                /* wait for resume to complete */
                usb_pause_mtx(NULL, hz / 4);

                /* clear write reference */
                USB_BUS_LOCK(udev->bus);
                udev->pwr_save.write_refs--;
                USB_BUS_UNLOCK(udev->bus);
#endif
                mode = USB_POWER_MODE_SAVE;
                break;

        case USB_POWER_MODE_SUSPEND:
#if USB_HAVE_POWERD
                /* let USB-powerd handle suspend */
                USB_BUS_LOCK(udev->bus);
                udev->pwr_save.last_xfer_time = ticks - (256 * hz);
                USB_BUS_UNLOCK(udev->bus);
#endif
                mode = USB_POWER_MODE_SAVE;
                break;

        default:
                return (EINVAL);
        }

        if (err)
                return (ENXIO);         /* I/O failure */

        /* if we are powered off we need to re-enumerate first */
        if (old_mode == USB_POWER_MODE_OFF) {
                if (udev->flags.usb_mode == USB_MODE_HOST &&
                    udev->re_enumerate_wait == USB_RE_ENUM_DONE) {
                        udev->re_enumerate_wait = USB_RE_ENUM_START;
                }
                /* set power mode will wake up the explore thread */
        }

        /* set new power mode */
        usbd_set_power_mode(udev, mode);

        return (0);                     /* success */
}

static int
ugen_get_power_mode(struct usb_fifo *f)
{
        struct usb_device *udev = f->udev;

        if (udev == NULL)
                return (USB_POWER_MODE_ON);

        return (udev->power_mode);
}

static int
ugen_get_port_path(struct usb_fifo *f, struct usb_device_port_path *dpp)
{
        struct usb_device *udev = f->udev;
        struct usb_device *next;
        unsigned int nlevel = 0;

        if (udev == NULL)
                goto error;

        dpp->udp_bus = device_get_unit(udev->bus->bdev);
        dpp->udp_index = udev->device_index;

        /* count port levels */
        next = udev;
        while (next->parent_hub != NULL) {
                nlevel++;
                next = next->parent_hub;
        }

        /* check if too many levels */
        if (nlevel > USB_DEVICE_PORT_PATH_MAX)
                goto error;

        /* store total level of ports */
        dpp->udp_port_level = nlevel;

        /* store port index array */
        next = udev;
        while (next->parent_hub != NULL) {
                dpp->udp_port_no[--nlevel] = next->port_no;
                next = next->parent_hub;
        }
        return (0);     /* success */

error:
        return (EINVAL);        /* failure */
}

static int
ugen_get_power_usage(struct usb_fifo *f)
{
        struct usb_device *udev = f->udev;

        if (udev == NULL)
                return (0);

        return (udev->power);
}

static int
ugen_do_port_feature(struct usb_fifo *f, uint8_t port_no,
    uint8_t set, uint16_t feature)
{
        struct usb_device *udev = f->udev;
        struct usb_hub *hub;
        int err;

        err = caps_priv_check_self(SYSCAP_NODRIVER);
        if (err)
                return (err);

        if (port_no == 0) {
                return (EINVAL);
        }
        if ((udev == NULL) ||
            (udev->hub == NULL)) {
                return (EINVAL);
        }
        hub = udev->hub;

        if (port_no > hub->nports) {
                return (EINVAL);
        }
        if (set)
                err = usbd_req_set_port_feature(udev,
                    NULL, port_no, feature);
        else
                err = usbd_req_clear_port_feature(udev,
                    NULL, port_no, feature);

        if (err)
                return (ENXIO);         /* failure */

        return (0);                     /* success */
}

static int
ugen_iface_ioctl(struct usb_fifo *f, u_long cmd, void *addr, int fflags)
{
        struct usb_fifo *f_rx;
        struct usb_fifo *f_tx;
        int error = 0;

        f_rx = f->udev->fifo[(f->fifo_index & ~1) + USB_FIFO_RX];
        f_tx = f->udev->fifo[(f->fifo_index & ~1) + USB_FIFO_TX];

        switch (cmd) {
        case USB_SET_RX_SHORT_XFER:
                if (fflags & FREAD) {
                        error = ugen_set_short_xfer(f_rx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_SET_TX_FORCE_SHORT:
                if (fflags & FWRITE) {
                        error = ugen_set_short_xfer(f_tx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_SET_RX_TIMEOUT:
                if (fflags & FREAD) {
                        error = ugen_set_timeout(f_rx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_SET_TX_TIMEOUT:
                if (fflags & FWRITE) {
                        error = ugen_set_timeout(f_tx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_GET_RX_FRAME_SIZE:
                if (fflags & FREAD) {
                        error = ugen_get_frame_size(f_rx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_GET_TX_FRAME_SIZE:
                if (fflags & FWRITE) {
                        error = ugen_get_frame_size(f_tx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_SET_RX_BUFFER_SIZE:
                if (fflags & FREAD) {
                        error = ugen_set_buffer_size(f_rx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_SET_TX_BUFFER_SIZE:
                if (fflags & FWRITE) {
                        error = ugen_set_buffer_size(f_tx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_GET_RX_BUFFER_SIZE:
                if (fflags & FREAD) {
                        error = ugen_get_buffer_size(f_rx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_GET_TX_BUFFER_SIZE:
                if (fflags & FWRITE) {
                        error = ugen_get_buffer_size(f_tx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_GET_RX_INTERFACE_DESC:
                if (fflags & FREAD) {
                        error = ugen_get_iface_desc(f_rx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_GET_TX_INTERFACE_DESC:
                if (fflags & FWRITE) {
                        error = ugen_get_iface_desc(f_tx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_GET_RX_ENDPOINT_DESC:
                if (fflags & FREAD) {
                        error = ugen_get_endpoint_desc(f_rx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_GET_TX_ENDPOINT_DESC:
                if (fflags & FWRITE) {
                        error = ugen_get_endpoint_desc(f_tx, addr);
                } else {
                        error = EINVAL;
                }
                break;

        case USB_SET_RX_STALL_FLAG:
                if ((fflags & FREAD) && (*(int *)addr)) {
                        f_rx->flag_stall = 1;
                }
                break;

        case USB_SET_TX_STALL_FLAG:
                if ((fflags & FWRITE) && (*(int *)addr)) {
                        f_tx->flag_stall = 1;
                }
                break;

        default:
                error = ENOIOCTL;
                break;
        }
        return (error);
}

static int
ugen_ioctl_post(struct usb_fifo *f, u_long cmd, void *addr, int fflags)
{
        union {
                struct usb_interface_descriptor *idesc;
                struct usb_alt_interface *ai;
                struct usb_device_descriptor *ddesc;
                struct usb_config_descriptor *cdesc;
                struct usb_device_stats *stat;
                struct usb_fs_init *pinit;
                struct usb_fs_uninit *puninit;
                struct usb_device_port_path *dpp;
                uint32_t *ptime;
                void   *addr;
                int    *pint;
        }     u;
        struct usb_device_descriptor *dtemp;
        struct usb_config_descriptor *ctemp;
        struct usb_interface *iface;
        int error = 0;
        uint8_t n;

        u.addr = addr;

        DPRINTFN(6, "cmd=0x%08lx\n", cmd);

        switch (cmd) {
        case USB_DISCOVER:
                usb_needs_explore_all();
                break;

        case USB_SETDEBUG:
                if (!(fflags & FWRITE)) {
                        error = EPERM;
                        break;
                }
                usb_debug = *(int *)addr;
                break;

        case USB_GET_CONFIG:
                *(int *)addr = f->udev->curr_config_index;
                break;

        case USB_SET_CONFIG:
                if (!(fflags & FWRITE)) {
                        error = EPERM;
                        break;
                }
                error = ugen_set_config(f, *(int *)addr);
                break;

        case USB_GET_ALTINTERFACE:
                iface = usbd_get_iface(f->udev,
                    u.ai->uai_interface_index);
                if (iface && iface->idesc) {
                        u.ai->uai_alt_index = iface->alt_index;
                } else {
                        error = EINVAL;
                }
                break;

        case USB_SET_ALTINTERFACE:
                if (!(fflags & FWRITE)) {
                        error = EPERM;
                        break;
                }
                error = ugen_set_interface(f,
                    u.ai->uai_interface_index, u.ai->uai_alt_index);
                break;

        case USB_GET_DEVICE_DESC:
                dtemp = usbd_get_device_descriptor(f->udev);
                if (!dtemp) {
                        error = EIO;
                        break;
                }
                *u.ddesc = *dtemp;
                break;

        case USB_GET_CONFIG_DESC:
                ctemp = usbd_get_config_descriptor(f->udev);
                if (!ctemp) {
                        error = EIO;
                        break;
                }
                *u.cdesc = *ctemp;
                break;

        case USB_GET_FULL_DESC:
                error = ugen_get_cdesc(f, addr);
                break;

        case USB_GET_STRING_DESC:
                error = ugen_get_sdesc(f, addr);
                break;

        case USB_GET_IFACE_DRIVER:
                error = ugen_get_iface_driver(f, addr);
                break;

        case USB_REQUEST:
        case USB_DO_REQUEST:
                if (!(fflags & FWRITE)) {
                        error = EPERM;
                        break;
                }
                error = ugen_do_request(f, addr);
                break;

        case USB_DEVICEINFO:
        case USB_GET_DEVICEINFO:
                error = usb_gen_fill_deviceinfo(f, addr);
                break;

        case USB_DEVICESTATS:
                for (n = 0; n != 4; n++) {

                        u.stat->uds_requests_fail[n] =
                            f->udev->bus->stats_err.uds_requests[n];

                        u.stat->uds_requests_ok[n] =
                            f->udev->bus->stats_ok.uds_requests[n];
                }
                break;

        case USB_DEVICEENUMERATE:
                error = ugen_re_enumerate(f);
                break;

        case USB_GET_PLUGTIME:
                *u.ptime = f->udev->plugtime;
                break;

        case USB_CLAIM_INTERFACE:
        case USB_RELEASE_INTERFACE:
                /* TODO */
                break;

        case USB_IFACE_DRIVER_ACTIVE:

                n = *u.pint & 0xFF;

                iface = usbd_get_iface(f->udev, n);

                if (iface && iface->subdev)
                        error = 0;
                else
                        error = ENXIO;
                break;

        case USB_IFACE_DRIVER_DETACH:

                error = caps_priv_check_self(SYSCAP_NODRIVER);
                if (error)
                        break;

                n = *u.pint & 0xFF;

                if (n == USB_IFACE_INDEX_ANY) {
                        error = EINVAL;
                        break;
                }

                /*
                 * Detach the currently attached driver.
                 */
                usb_detach_device(f->udev, n, 0);

                /*
                 * Set parent to self, this should keep attach away
                 * until the next set configuration event.
                 */
                usbd_set_parent_iface(f->udev, n, n);
                break;

        case USB_SET_POWER_MODE:
                error = ugen_set_power_mode(f, *u.pint);
                break;

        case USB_GET_POWER_MODE:
                *u.pint = ugen_get_power_mode(f);
                break;

        case USB_GET_DEV_PORT_PATH:
                error = ugen_get_port_path(f, u.dpp);
                break;

        case USB_GET_POWER_USAGE:
                *u.pint = ugen_get_power_usage(f);
                break;

        case USB_SET_PORT_ENABLE:
                error = ugen_do_port_feature(f,
                    *u.pint, 1, UHF_PORT_ENABLE);
                break;

        case USB_SET_PORT_DISABLE:
                error = ugen_do_port_feature(f,
                    *u.pint, 0, UHF_PORT_ENABLE);
                break;

        case USB_FS_INIT:
                /* verify input parameters */
                if (u.pinit->pEndpoints == NULL) {
                        error = EINVAL;
                        break;
                }
                if (u.pinit->ep_index_max > 127) {
                        error = EINVAL;
                        break;
                }
                if (u.pinit->ep_index_max == 0) {
                        error = EINVAL;
                        break;
                }
                if (f->fs_xfer != NULL) {
                        error = EBUSY;
                        break;
                }
                if (f->dev_ep_index != 0) {
                        error = EINVAL;
                        break;
                }
                if (ugen_fifo_in_use(f, fflags)) {
                        error = EBUSY;
                        break;
                }
                error = usb_fifo_alloc_buffer(f, 1, u.pinit->ep_index_max);
                if (error) {
                        break;
                }
                f->fs_xfer = kmalloc(sizeof(f->fs_xfer[0]) *
                    u.pinit->ep_index_max, M_USB, M_WAITOK | M_ZERO);
                if (f->fs_xfer == NULL) {
                        usb_fifo_free_buffer(f);
                        error = ENOMEM;
                        break;
                }
                f->fs_ep_max = u.pinit->ep_index_max;
                f->fs_ep_ptr = u.pinit->pEndpoints;
                break;

        case USB_FS_UNINIT:
                if (u.puninit->dummy != 0) {
                        error = EINVAL;
                        break;
                }
                error = ugen_fs_uninit(f);
                break;

        default:
                lockmgr(f->priv_lock, LK_EXCLUSIVE);
                error = ugen_iface_ioctl(f, cmd, addr, fflags);
                lockmgr(f->priv_lock, LK_RELEASE);
                break;
        }
        DPRINTFN(6, "error=%d\n", error);
        return (error);
}

static void
ugen_ctrl_fs_callback(struct usb_xfer *xfer, usb_error_t error)
{
        ;                               /* workaround for a bug in "indent" */

        DPRINTF("st=%u alen=%u aframes=%u\n",
            USB_GET_STATE(xfer), xfer->actlen, xfer->aframes);

        switch (USB_GET_STATE(xfer)) {
        case USB_ST_SETUP:
                usbd_transfer_submit(xfer);
                break;
        default:
                ugen_fs_set_complete(xfer->priv_sc, USB_P2U(xfer->priv_fifo));
                break;
        }
}
#endif  /* USB_HAVE_UGEN */