Archipelago » qemu

/*

 * QEMU USB emulation

 *

 * Copyright (c) 2005 Fabrice Bellard

 *

 * 2008 Generic packet handler rewrite by Max Krasnyansky

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

#include "qemu-common.h"

#include "hw/usb.h"

#include "qemu/iov.h"

#include "trace.h"

void usb_attach(USBPort *port)

{

    USBDevice *dev = port->dev;

    assert(dev != NULL);

    assert(dev->attached);

    assert(dev->state == USB_STATE_NOTATTACHED);

    port->ops->attach(port);

    dev->state = USB_STATE_ATTACHED;

    usb_device_handle_attach(dev);

}

void usb_detach(USBPort *port)

{

    USBDevice *dev = port->dev;

    assert(dev != NULL);

    assert(dev->state != USB_STATE_NOTATTACHED);

    port->ops->detach(port);

    dev->state = USB_STATE_NOTATTACHED;

}

void usb_port_reset(USBPort *port)

{

    USBDevice *dev = port->dev;

    assert(dev != NULL);

    usb_detach(port);

    usb_attach(port);

    usb_device_reset(dev);

}

void usb_device_reset(USBDevice *dev)

{

    if (dev == NULL || !dev->attached) {

        return;

    }

    dev->remote_wakeup = 0;

    dev->addr = 0;

    dev->state = USB_STATE_DEFAULT;

    usb_device_handle_reset(dev);

}

void usb_wakeup(USBEndpoint *ep)

{

    USBDevice *dev = ep->dev;

    USBBus *bus = usb_bus_from_device(dev);

    if (dev->remote_wakeup && dev->port && dev->port->ops->wakeup) {

        dev->port->ops->wakeup(dev->port);

    }

    if (bus->ops->wakeup_endpoint) {

        bus->ops->wakeup_endpoint(bus, ep);

    }

}

/**********************/

/* generic USB device helpers (you are not forced to use them when

   writing your USB device driver, but they help handling the

   protocol)

*/

#define SETUP_STATE_IDLE  0

#define SETUP_STATE_SETUP 1

#define SETUP_STATE_DATA  2

#define SETUP_STATE_ACK   3

#define SETUP_STATE_PARAM 4

static void do_token_setup(USBDevice *s, USBPacket *p)

{

    int request, value, index;

    if (p->iov.size != 8) {

        p->status = USB_RET_STALL;

        return;

    }

    usb_packet_copy(p, s->setup_buf, p->iov.size);

    p->actual_length = 0;

    s->setup_len   = (s->setup_buf[7] << 8) | s->setup_buf[6];

    s->setup_index = 0;

    request = (s->setup_buf[0] << 8) | s->setup_buf[1];

    value   = (s->setup_buf[3] << 8) | s->setup_buf[2];

    index   = (s->setup_buf[5] << 8) | s->setup_buf[4];

    if (s->setup_buf[0] & USB_DIR_IN) {

        usb_device_handle_control(s, p, request, value, index,

                                  s->setup_len, s->data_buf);

        if (p->status == USB_RET_ASYNC) {

            s->setup_state = SETUP_STATE_SETUP;

        }

        if (p->status != USB_RET_SUCCESS) {

            return;

        }

        if (p->actual_length < s->setup_len) {

            s->setup_len = p->actual_length;

        }

        s->setup_state = SETUP_STATE_DATA;

    } else {

        if (s->setup_len > sizeof(s->data_buf)) {

            fprintf(stderr,

                "usb_generic_handle_packet: ctrl buffer too small (%d > %zu)\n",

                s->setup_len, sizeof(s->data_buf));

            p->status = USB_RET_STALL;

            return;

        }

        if (s->setup_len == 0)

            s->setup_state = SETUP_STATE_ACK;

        else

            s->setup_state = SETUP_STATE_DATA;

    }

    p->actual_length = 8;

}

static void do_token_in(USBDevice *s, USBPacket *p)

{

    int request, value, index;

    assert(p->ep->nr == 0);

    request = (s->setup_buf[0] << 8) | s->setup_buf[1];

    value   = (s->setup_buf[3] << 8) | s->setup_buf[2];

    index   = (s->setup_buf[5] << 8) | s->setup_buf[4];

    switch(s->setup_state) {

    case SETUP_STATE_ACK:

        if (!(s->setup_buf[0] & USB_DIR_IN)) {

            usb_device_handle_control(s, p, request, value, index,

                                      s->setup_len, s->data_buf);

            if (p->status == USB_RET_ASYNC) {

                return;

            }

            s->setup_state = SETUP_STATE_IDLE;

            p->actual_length = 0;

        }

        break;

    case SETUP_STATE_DATA:

        if (s->setup_buf[0] & USB_DIR_IN) {

            int len = s->setup_len - s->setup_index;

            if (len > p->iov.size) {

                len = p->iov.size;

            }

            usb_packet_copy(p, s->data_buf + s->setup_index, len);

            s->setup_index += len;

            if (s->setup_index >= s->setup_len) {

                s->setup_state = SETUP_STATE_ACK;

            }

            return;

        }

        s->setup_state = SETUP_STATE_IDLE;

        p->status = USB_RET_STALL;

        break;

    default:

        p->status = USB_RET_STALL;

    }

}

static void do_token_out(USBDevice *s, USBPacket *p)

{

    assert(p->ep->nr == 0);

    switch(s->setup_state) {

    case SETUP_STATE_ACK:

        if (s->setup_buf[0] & USB_DIR_IN) {

            s->setup_state = SETUP_STATE_IDLE;

            /* transfer OK */

        } else {

            /* ignore additional output */

        }

        break;

    case SETUP_STATE_DATA:

        if (!(s->setup_buf[0] & USB_DIR_IN)) {

            int len = s->setup_len - s->setup_index;

            if (len > p->iov.size) {

                len = p->iov.size;

            }

            usb_packet_copy(p, s->data_buf + s->setup_index, len);

            s->setup_index += len;

            if (s->setup_index >= s->setup_len) {

                s->setup_state = SETUP_STATE_ACK;

            }

            return;

        }

        s->setup_state = SETUP_STATE_IDLE;

        p->status = USB_RET_STALL;

        break;

    default:

        p->status = USB_RET_STALL;

    }

}

static void do_parameter(USBDevice *s, USBPacket *p)

{

    int i, request, value, index;

    for (i = 0; i < 8; i++) {

        s->setup_buf[i] = p->parameter >> (i*8);

    }

    s->setup_state = SETUP_STATE_PARAM;

    s->setup_len   = (s->setup_buf[7] << 8) | s->setup_buf[6];

    s->setup_index = 0;

    request = (s->setup_buf[0] << 8) | s->setup_buf[1];

    value   = (s->setup_buf[3] << 8) | s->setup_buf[2];

    index   = (s->setup_buf[5] << 8) | s->setup_buf[4];

    if (s->setup_len > sizeof(s->data_buf)) {

        fprintf(stderr,

                "usb_generic_handle_packet: ctrl buffer too small (%d > %zu)\n",

                s->setup_len, sizeof(s->data_buf));

        p->status = USB_RET_STALL;

        return;

    }

    if (p->pid == USB_TOKEN_OUT) {

        usb_packet_copy(p, s->data_buf, s->setup_len);

    }

    usb_device_handle_control(s, p, request, value, index,

                              s->setup_len, s->data_buf);

    if (p->status == USB_RET_ASYNC) {

        return;

    }

    if (p->actual_length < s->setup_len) {

        s->setup_len = p->actual_length;

    }

    if (p->pid == USB_TOKEN_IN) {

        p->actual_length = 0;

        usb_packet_copy(p, s->data_buf, s->setup_len);

    }

}

/* ctrl complete function for devices which use usb_generic_handle_packet and

   may return USB_RET_ASYNC from their handle_control callback. Device code

   which does this *must* call this function instead of the normal

   usb_packet_complete to complete their async control packets. */

void usb_generic_async_ctrl_complete(USBDevice *s, USBPacket *p)

{

    if (p->status < 0) {

        s->setup_state = SETUP_STATE_IDLE;

    }

    switch (s->setup_state) {

    case SETUP_STATE_SETUP:

        if (p->actual_length < s->setup_len) {

            s->setup_len = p->actual_length;

        }

        s->setup_state = SETUP_STATE_DATA;

        p->actual_length = 8;

        break;

    case SETUP_STATE_ACK:

        s->setup_state = SETUP_STATE_IDLE;

        p->actual_length = 0;

        break;

    case SETUP_STATE_PARAM:

        if (p->actual_length < s->setup_len) {

            s->setup_len = p->actual_length;

        }

        if (p->pid == USB_TOKEN_IN) {

            p->actual_length = 0;

            usb_packet_copy(p, s->data_buf, s->setup_len);

        }

        break;

    default:

        break;

    }

    usb_packet_complete(s, p);

}

/* XXX: fix overflow */

int set_usb_string(uint8_t *buf, const char *str)

{

    int len, i;

    uint8_t *q;

    q = buf;

    len = strlen(str);

    *q++ = 2 * len + 2;

    *q++ = 3;

    for(i = 0; i < len; i++) {

        *q++ = str[i];

        *q++ = 0;

    }

    return q - buf;

}

USBDevice *usb_find_device(USBPort *port, uint8_t addr)

{

    USBDevice *dev = port->dev;

    if (dev == NULL || !dev->attached || dev->state != USB_STATE_DEFAULT) {

        return NULL;

    }

    if (dev->addr == addr) {

        return dev;

    }

    return usb_device_find_device(dev, addr);

}

static void usb_process_one(USBPacket *p)

{

    USBDevice *dev = p->ep->dev;

    /*

     * Handlers expect status to be initialized to USB_RET_SUCCESS, but it

     * can be USB_RET_NAK here from a previous usb_process_one() call,

     * or USB_RET_ASYNC from going through usb_queue_one().

     */

    p->status = USB_RET_SUCCESS;

    if (p->ep->nr == 0) {

        /* control pipe */

        if (p->parameter) {

            do_parameter(dev, p);

            return;

        }

        switch (p->pid) {

        case USB_TOKEN_SETUP:

            do_token_setup(dev, p);

            break;

        case USB_TOKEN_IN:

            do_token_in(dev, p);

            break;

        case USB_TOKEN_OUT:

            do_token_out(dev, p);

            break;

        default:

            p->status = USB_RET_STALL;

        }

    } else {

        /* data pipe */

        usb_device_handle_data(dev, p);

    }

}

static void usb_queue_one(USBPacket *p)

{

    usb_packet_set_state(p, USB_PACKET_QUEUED);

    QTAILQ_INSERT_TAIL(&p->ep->queue, p, queue);

    p->status = USB_RET_ASYNC;

}

/* Hand over a packet to a device for processing.  p->status ==

   USB_RET_ASYNC indicates the processing isn't finished yet, the

   driver will call usb_packet_complete() when done processing it. */

void usb_handle_packet(USBDevice *dev, USBPacket *p)

{

    if (dev == NULL) {

        p->status = USB_RET_NODEV;

        return;

    }

    assert(dev == p->ep->dev);

    assert(dev->state == USB_STATE_DEFAULT);

    usb_packet_check_state(p, USB_PACKET_SETUP);

    assert(p->ep != NULL);

    /* Submitting a new packet clears halt */

    if (p->ep->halted) {

        assert(QTAILQ_EMPTY(&p->ep->queue));

        p->ep->halted = false;

    }

    if (QTAILQ_EMPTY(&p->ep->queue) || p->ep->pipeline) {

        usb_process_one(p);

        if (p->status == USB_RET_ASYNC) {

            /* hcd drivers cannot handle async for isoc */

            assert(p->ep->type != USB_ENDPOINT_XFER_ISOC);

            /* using async for interrupt packets breaks migration */

            assert(p->ep->type != USB_ENDPOINT_XFER_INT ||

                   (dev->flags & USB_DEV_FLAG_IS_HOST));

            usb_packet_set_state(p, USB_PACKET_ASYNC);

            QTAILQ_INSERT_TAIL(&p->ep->queue, p, queue);

        } else if (p->status == USB_RET_ADD_TO_QUEUE) {

            usb_queue_one(p);

        } else {

            /*

             * When pipelining is enabled usb-devices must always return async,

             * otherwise packets can complete out of order!

             */

            assert(!p->ep->pipeline || QTAILQ_EMPTY(&p->ep->queue));

            if (p->status != USB_RET_NAK) {

                usb_packet_set_state(p, USB_PACKET_COMPLETE);

            }

        }

    } else {

        usb_queue_one(p);

    }

}

void usb_packet_complete_one(USBDevice *dev, USBPacket *p)

{

    USBEndpoint *ep = p->ep;

    assert(QTAILQ_FIRST(&ep->queue) == p);

    assert(p->status != USB_RET_ASYNC && p->status != USB_RET_NAK);

    if (p->status != USB_RET_SUCCESS ||

            (p->short_not_ok && (p->actual_length < p->iov.size))) {

        ep->halted = true;

    }

    usb_packet_set_state(p, USB_PACKET_COMPLETE);

    QTAILQ_REMOVE(&ep->queue, p, queue);

    dev->port->ops->complete(dev->port, p);

}

/* Notify the controller that an async packet is complete.  This should only

   be called for packets previously deferred by returning USB_RET_ASYNC from

   handle_packet. */

void usb_packet_complete(USBDevice *dev, USBPacket *p)

{

    USBEndpoint *ep = p->ep;

    usb_packet_check_state(p, USB_PACKET_ASYNC);

    usb_packet_complete_one(dev, p);

    while (!QTAILQ_EMPTY(&ep->queue)) {

        p = QTAILQ_FIRST(&ep->queue);

        if (ep->halted) {

            /* Empty the queue on a halt */

            p->status = USB_RET_REMOVE_FROM_QUEUE;

            dev->port->ops->complete(dev->port, p);

            continue;

        }

        if (p->state == USB_PACKET_ASYNC) {

            break;

        }

        usb_packet_check_state(p, USB_PACKET_QUEUED);

        usb_process_one(p);

        if (p->status == USB_RET_ASYNC) {

            usb_packet_set_state(p, USB_PACKET_ASYNC);

            break;

        }

        usb_packet_complete_one(ep->dev, p);

    }

}

/* Cancel an active packet.  The packed must have been deferred by

   returning USB_RET_ASYNC from handle_packet, and not yet

   completed.  */

void usb_cancel_packet(USBPacket * p)

{

    bool callback = (p->state == USB_PACKET_ASYNC);

    assert(usb_packet_is_inflight(p));

    usb_packet_set_state(p, USB_PACKET_CANCELED);

    QTAILQ_REMOVE(&p->ep->queue, p, queue);

    if (callback) {

        usb_device_cancel_packet(p->ep->dev, p);

    }

}

void usb_packet_init(USBPacket *p)

{

    qemu_iovec_init(&p->iov, 1);

}

static const char *usb_packet_state_name(USBPacketState state)

{

    static const char *name[] = {

        [USB_PACKET_UNDEFINED] = "undef",

        [USB_PACKET_SETUP]     = "setup",

        [USB_PACKET_QUEUED]    = "queued",

        [USB_PACKET_ASYNC]     = "async",

        [USB_PACKET_COMPLETE]  = "complete",

        [USB_PACKET_CANCELED]  = "canceled",

    };

    if (state < ARRAY_SIZE(name)) {

        return name[state];

    }

    return "INVALID";

}

void usb_packet_check_state(USBPacket *p, USBPacketState expected)

{

    USBDevice *dev;

    USBBus *bus;

    if (p->state == expected) {

        return;

    }

    dev = p->ep->dev;

    bus = usb_bus_from_device(dev);

    trace_usb_packet_state_fault(bus->busnr, dev->port->path, p->ep->nr, p,

                                 usb_packet_state_name(p->state),

                                 usb_packet_state_name(expected));

    assert(!"usb packet state check failed");

}

void usb_packet_set_state(USBPacket *p, USBPacketState state)

{

    if (p->ep) {

        USBDevice *dev = p->ep->dev;

        USBBus *bus = usb_bus_from_device(dev);

        trace_usb_packet_state_change(bus->busnr, dev->port->path, p->ep->nr, p,

                                      usb_packet_state_name(p->state),

                                      usb_packet_state_name(state));

    } else {

        trace_usb_packet_state_change(-1, "", -1, p,

                                      usb_packet_state_name(p->state),

                                      usb_packet_state_name(state));

    }

    p->state = state;

}

void usb_packet_setup(USBPacket *p, int pid, USBEndpoint *ep, uint64_t id,

                      bool short_not_ok, bool int_req)

{

    assert(!usb_packet_is_inflight(p));

    assert(p->iov.iov != NULL);

    p->id = id;

    p->pid = pid;

    p->ep = ep;

    p->status = USB_RET_SUCCESS;

    p->actual_length = 0;

    p->parameter = 0;

    p->short_not_ok = short_not_ok;

    p->int_req = int_req;

    p->combined = NULL;

    qemu_iovec_reset(&p->iov);

    usb_packet_set_state(p, USB_PACKET_SETUP);

}

void usb_packet_addbuf(USBPacket *p, void *ptr, size_t len)

{

    qemu_iovec_add(&p->iov, ptr, len);

}

void usb_packet_copy(USBPacket *p, void *ptr, size_t bytes)

{

    assert(p->actual_length >= 0);

    assert(p->actual_length + bytes <= p->iov.size);

    switch (p->pid) {

    case USB_TOKEN_SETUP:

    case USB_TOKEN_OUT:

        iov_to_buf(p->iov.iov, p->iov.niov, p->actual_length, ptr, bytes);

        break;

    case USB_TOKEN_IN:

        iov_from_buf(p->iov.iov, p->iov.niov, p->actual_length, ptr, bytes);

        break;

    default:

        fprintf(stderr, "%s: invalid pid: %x\n", __func__, p->pid);

        abort();

    }

    p->actual_length += bytes;

}

void usb_packet_skip(USBPacket *p, size_t bytes)

{

    assert(p->actual_length >= 0);

    assert(p->actual_length + bytes <= p->iov.size);

    if (p->pid == USB_TOKEN_IN) {

        iov_memset(p->iov.iov, p->iov.niov, p->actual_length, 0, bytes);

    }

    p->actual_length += bytes;

}

void usb_packet_cleanup(USBPacket *p)

{

    assert(!usb_packet_is_inflight(p));

    qemu_iovec_destroy(&p->iov);

}

void usb_ep_reset(USBDevice *dev)

{

    int ep;

    dev->ep_ctl.nr = 0;

    dev->ep_ctl.type = USB_ENDPOINT_XFER_CONTROL;

    dev->ep_ctl.ifnum = 0;

    dev->ep_ctl.dev = dev;

    dev->ep_ctl.pipeline = false;

    for (ep = 0; ep < USB_MAX_ENDPOINTS; ep++) {

        dev->ep_in[ep].nr = ep + 1;

        dev->ep_out[ep].nr = ep + 1;

        dev->ep_in[ep].pid = USB_TOKEN_IN;

        dev->ep_out[ep].pid = USB_TOKEN_OUT;

        dev->ep_in[ep].type = USB_ENDPOINT_XFER_INVALID;

        dev->ep_out[ep].type = USB_ENDPOINT_XFER_INVALID;

        dev->ep_in[ep].ifnum = USB_INTERFACE_INVALID;

        dev->ep_out[ep].ifnum = USB_INTERFACE_INVALID;

        dev->ep_in[ep].dev = dev;

        dev->ep_out[ep].dev = dev;

        dev->ep_in[ep].pipeline = false;

        dev->ep_out[ep].pipeline = false;

    }

}

void usb_ep_init(USBDevice *dev)

{

    int ep;

    usb_ep_reset(dev);

    QTAILQ_INIT(&dev->ep_ctl.queue);

    for (ep = 0; ep < USB_MAX_ENDPOINTS; ep++) {

        QTAILQ_INIT(&dev->ep_in[ep].queue);

        QTAILQ_INIT(&dev->ep_out[ep].queue);

    }

}

void usb_ep_dump(USBDevice *dev)

{

    static const char *tname[] = {

        [USB_ENDPOINT_XFER_CONTROL] = "control",

        [USB_ENDPOINT_XFER_ISOC]    = "isoc",

        [USB_ENDPOINT_XFER_BULK]    = "bulk",

        [USB_ENDPOINT_XFER_INT]     = "int",

    };

    int ifnum, ep, first;

    fprintf(stderr, "Device \"%s\", config %d\n",

            dev->product_desc, dev->configuration);

    for (ifnum = 0; ifnum < 16; ifnum++) {

        first = 1;

        for (ep = 0; ep < USB_MAX_ENDPOINTS; ep++) {

            if (dev->ep_in[ep].type != USB_ENDPOINT_XFER_INVALID &&

                dev->ep_in[ep].ifnum == ifnum) {

                if (first) {

                    first = 0;

                    fprintf(stderr, "  Interface %d, alternative %d\n",

                            ifnum, dev->altsetting[ifnum]);

                }

                fprintf(stderr, "    Endpoint %d, IN, %s, %d max\n", ep,

                        tname[dev->ep_in[ep].type],

                        dev->ep_in[ep].max_packet_size);

            }

            if (dev->ep_out[ep].type != USB_ENDPOINT_XFER_INVALID &&

                dev->ep_out[ep].ifnum == ifnum) {

                if (first) {

                    first = 0;

                    fprintf(stderr, "  Interface %d, alternative %d\n",

                            ifnum, dev->altsetting[ifnum]);

                }

                fprintf(stderr, "    Endpoint %d, OUT, %s, %d max\n", ep,

                        tname[dev->ep_out[ep].type],

                        dev->ep_out[ep].max_packet_size);

            }

        }

    }

    fprintf(stderr, "--\n");

}

struct USBEndpoint *usb_ep_get(USBDevice *dev, int pid, int ep)

{

    struct USBEndpoint *eps;

    if (dev == NULL) {

        return NULL;

    }

    eps = (pid == USB_TOKEN_IN) ? dev->ep_in : dev->ep_out;

    if (ep == 0) {

        return &dev->ep_ctl;

    }

    assert(pid == USB_TOKEN_IN || pid == USB_TOKEN_OUT);

    assert(ep > 0 && ep <= USB_MAX_ENDPOINTS);

    return eps + ep - 1;

}

uint8_t usb_ep_get_type(USBDevice *dev, int pid, int ep)

{

    struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);

    return uep->type;

}

void usb_ep_set_type(USBDevice *dev, int pid, int ep, uint8_t type)

{

    struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);

    uep->type = type;

}

uint8_t usb_ep_get_ifnum(USBDevice *dev, int pid, int ep)

{

    struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);

    return uep->ifnum;

}

void usb_ep_set_ifnum(USBDevice *dev, int pid, int ep, uint8_t ifnum)

{

    struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);

    uep->ifnum = ifnum;

}

void usb_ep_set_max_packet_size(USBDevice *dev, int pid, int ep,

                                uint16_t raw)

{

    struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);

    int size, microframes;

    size = raw & 0x7ff;

    switch ((raw >> 11) & 3) {

    case 1:

        microframes = 2;

        break;

    case 2:

        microframes = 3;

        break;

    default:

        microframes = 1;

        break;

    }

    uep->max_packet_size = size * microframes;

}

int usb_ep_get_max_packet_size(USBDevice *dev, int pid, int ep)

{

    struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);

    return uep->max_packet_size;

}

void usb_ep_set_pipeline(USBDevice *dev, int pid, int ep, bool enabled)

{

    struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);

    uep->pipeline = enabled;

}

USBPacket *usb_ep_find_packet_by_id(USBDevice *dev, int pid, int ep,

                                    uint64_t id)

{

    struct USBEndpoint *uep = usb_ep_get(dev, pid, ep);

    USBPacket *p;

    QTAILQ_FOREACH(p, &uep->queue, queue) {

        if (p->id == id) {

            return p;

        }

    }

    return NULL;

}