qemu/hw/usb/desc.c
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   1#include <ctype.h>
   2
   3#include "hw/usb.h"
   4#include "hw/usb/desc.h"
   5#include "trace.h"
   6
   7/* ------------------------------------------------------------------ */
   8
   9static uint8_t usb_lo(uint16_t val)
  10{
  11    return val & 0xff;
  12}
  13
  14static uint8_t usb_hi(uint16_t val)
  15{
  16    return (val >> 8) & 0xff;
  17}
  18
  19int usb_desc_device(const USBDescID *id, const USBDescDevice *dev,
  20                    uint8_t *dest, size_t len)
  21{
  22    uint8_t bLength = 0x12;
  23    USBDescriptor *d = (void *)dest;
  24
  25    if (len < bLength) {
  26        return -1;
  27    }
  28
  29    d->bLength                     = bLength;
  30    d->bDescriptorType             = USB_DT_DEVICE;
  31
  32    d->u.device.bcdUSB_lo          = usb_lo(dev->bcdUSB);
  33    d->u.device.bcdUSB_hi          = usb_hi(dev->bcdUSB);
  34    d->u.device.bDeviceClass       = dev->bDeviceClass;
  35    d->u.device.bDeviceSubClass    = dev->bDeviceSubClass;
  36    d->u.device.bDeviceProtocol    = dev->bDeviceProtocol;
  37    d->u.device.bMaxPacketSize0    = dev->bMaxPacketSize0;
  38
  39    d->u.device.idVendor_lo        = usb_lo(id->idVendor);
  40    d->u.device.idVendor_hi        = usb_hi(id->idVendor);
  41    d->u.device.idProduct_lo       = usb_lo(id->idProduct);
  42    d->u.device.idProduct_hi       = usb_hi(id->idProduct);
  43    d->u.device.bcdDevice_lo       = usb_lo(id->bcdDevice);
  44    d->u.device.bcdDevice_hi       = usb_hi(id->bcdDevice);
  45    d->u.device.iManufacturer      = id->iManufacturer;
  46    d->u.device.iProduct           = id->iProduct;
  47    d->u.device.iSerialNumber      = id->iSerialNumber;
  48
  49    d->u.device.bNumConfigurations = dev->bNumConfigurations;
  50
  51    return bLength;
  52}
  53
  54int usb_desc_device_qualifier(const USBDescDevice *dev,
  55                              uint8_t *dest, size_t len)
  56{
  57    uint8_t bLength = 0x0a;
  58    USBDescriptor *d = (void *)dest;
  59
  60    if (len < bLength) {
  61        return -1;
  62    }
  63
  64    d->bLength                               = bLength;
  65    d->bDescriptorType                       = USB_DT_DEVICE_QUALIFIER;
  66
  67    d->u.device_qualifier.bcdUSB_lo          = usb_lo(dev->bcdUSB);
  68    d->u.device_qualifier.bcdUSB_hi          = usb_hi(dev->bcdUSB);
  69    d->u.device_qualifier.bDeviceClass       = dev->bDeviceClass;
  70    d->u.device_qualifier.bDeviceSubClass    = dev->bDeviceSubClass;
  71    d->u.device_qualifier.bDeviceProtocol    = dev->bDeviceProtocol;
  72    d->u.device_qualifier.bMaxPacketSize0    = dev->bMaxPacketSize0;
  73    d->u.device_qualifier.bNumConfigurations = dev->bNumConfigurations;
  74    d->u.device_qualifier.bReserved          = 0;
  75
  76    return bLength;
  77}
  78
  79int usb_desc_config(const USBDescConfig *conf, int flags,
  80                    uint8_t *dest, size_t len)
  81{
  82    uint8_t  bLength = 0x09;
  83    uint16_t wTotalLength = 0;
  84    USBDescriptor *d = (void *)dest;
  85    int i, rc;
  86
  87    if (len < bLength) {
  88        return -1;
  89    }
  90
  91    d->bLength                      = bLength;
  92    d->bDescriptorType              = USB_DT_CONFIG;
  93
  94    d->u.config.bNumInterfaces      = conf->bNumInterfaces;
  95    d->u.config.bConfigurationValue = conf->bConfigurationValue;
  96    d->u.config.iConfiguration      = conf->iConfiguration;
  97    d->u.config.bmAttributes        = conf->bmAttributes;
  98    d->u.config.bMaxPower           = conf->bMaxPower;
  99    wTotalLength += bLength;
 100
 101    /* handle grouped interfaces if any */
 102    for (i = 0; i < conf->nif_groups; i++) {
 103        rc = usb_desc_iface_group(&(conf->if_groups[i]), flags,
 104                                  dest + wTotalLength,
 105                                  len - wTotalLength);
 106        if (rc < 0) {
 107            return rc;
 108        }
 109        wTotalLength += rc;
 110    }
 111
 112    /* handle normal (ungrouped / no IAD) interfaces if any */
 113    for (i = 0; i < conf->nif; i++) {
 114        rc = usb_desc_iface(conf->ifs + i, flags,
 115                            dest + wTotalLength, len - wTotalLength);
 116        if (rc < 0) {
 117            return rc;
 118        }
 119        wTotalLength += rc;
 120    }
 121
 122    d->u.config.wTotalLength_lo = usb_lo(wTotalLength);
 123    d->u.config.wTotalLength_hi = usb_hi(wTotalLength);
 124    return wTotalLength;
 125}
 126
 127int usb_desc_iface_group(const USBDescIfaceAssoc *iad, int flags,
 128                         uint8_t *dest, size_t len)
 129{
 130    int pos = 0;
 131    int i = 0;
 132
 133    /* handle interface association descriptor */
 134    uint8_t bLength = 0x08;
 135
 136    if (len < bLength) {
 137        return -1;
 138    }
 139
 140    dest[0x00] = bLength;
 141    dest[0x01] = USB_DT_INTERFACE_ASSOC;
 142    dest[0x02] = iad->bFirstInterface;
 143    dest[0x03] = iad->bInterfaceCount;
 144    dest[0x04] = iad->bFunctionClass;
 145    dest[0x05] = iad->bFunctionSubClass;
 146    dest[0x06] = iad->bFunctionProtocol;
 147    dest[0x07] = iad->iFunction;
 148    pos += bLength;
 149
 150    /* handle associated interfaces in this group */
 151    for (i = 0; i < iad->nif; i++) {
 152        int rc = usb_desc_iface(&(iad->ifs[i]), flags, dest + pos, len - pos);
 153        if (rc < 0) {
 154            return rc;
 155        }
 156        pos += rc;
 157    }
 158
 159    return pos;
 160}
 161
 162int usb_desc_iface(const USBDescIface *iface, int flags,
 163                   uint8_t *dest, size_t len)
 164{
 165    uint8_t bLength = 0x09;
 166    int i, rc, pos = 0;
 167    USBDescriptor *d = (void *)dest;
 168
 169    if (len < bLength) {
 170        return -1;
 171    }
 172
 173    d->bLength                        = bLength;
 174    d->bDescriptorType                = USB_DT_INTERFACE;
 175
 176    d->u.interface.bInterfaceNumber   = iface->bInterfaceNumber;
 177    d->u.interface.bAlternateSetting  = iface->bAlternateSetting;
 178    d->u.interface.bNumEndpoints      = iface->bNumEndpoints;
 179    d->u.interface.bInterfaceClass    = iface->bInterfaceClass;
 180    d->u.interface.bInterfaceSubClass = iface->bInterfaceSubClass;
 181    d->u.interface.bInterfaceProtocol = iface->bInterfaceProtocol;
 182    d->u.interface.iInterface         = iface->iInterface;
 183    pos += bLength;
 184
 185    for (i = 0; i < iface->ndesc; i++) {
 186        rc = usb_desc_other(iface->descs + i, dest + pos, len - pos);
 187        if (rc < 0) {
 188            return rc;
 189        }
 190        pos += rc;
 191    }
 192
 193    for (i = 0; i < iface->bNumEndpoints; i++) {
 194        rc = usb_desc_endpoint(iface->eps + i, flags, dest + pos, len - pos);
 195        if (rc < 0) {
 196            return rc;
 197        }
 198        pos += rc;
 199    }
 200
 201    return pos;
 202}
 203
 204int usb_desc_endpoint(const USBDescEndpoint *ep, int flags,
 205                      uint8_t *dest, size_t len)
 206{
 207    uint8_t bLength = ep->is_audio ? 0x09 : 0x07;
 208    uint8_t extralen = ep->extra ? ep->extra[0] : 0;
 209    uint8_t superlen = (flags & USB_DESC_FLAG_SUPER) ? 0x06 : 0;
 210    USBDescriptor *d = (void *)dest;
 211
 212    if (len < bLength + extralen + superlen) {
 213        return -1;
 214    }
 215
 216    d->bLength                      = bLength;
 217    d->bDescriptorType              = USB_DT_ENDPOINT;
 218
 219    d->u.endpoint.bEndpointAddress  = ep->bEndpointAddress;
 220    d->u.endpoint.bmAttributes      = ep->bmAttributes;
 221    d->u.endpoint.wMaxPacketSize_lo = usb_lo(ep->wMaxPacketSize);
 222    d->u.endpoint.wMaxPacketSize_hi = usb_hi(ep->wMaxPacketSize);
 223    d->u.endpoint.bInterval         = ep->bInterval;
 224    if (ep->is_audio) {
 225        d->u.endpoint.bRefresh      = ep->bRefresh;
 226        d->u.endpoint.bSynchAddress = ep->bSynchAddress;
 227    }
 228
 229    if (superlen) {
 230        USBDescriptor *d = (void *)(dest + bLength);
 231
 232        d->bLength                       = 0x06;
 233        d->bDescriptorType               = USB_DT_ENDPOINT_COMPANION;
 234
 235        d->u.super_endpoint.bMaxBurst    = ep->bMaxBurst;
 236        d->u.super_endpoint.bmAttributes = ep->bmAttributes_super;
 237        d->u.super_endpoint.wBytesPerInterval_lo =
 238            usb_lo(ep->wBytesPerInterval);
 239        d->u.super_endpoint.wBytesPerInterval_hi =
 240            usb_hi(ep->wBytesPerInterval);
 241    }
 242
 243    if (ep->extra) {
 244        memcpy(dest + bLength + superlen, ep->extra, extralen);
 245    }
 246
 247    return bLength + extralen + superlen;
 248}
 249
 250int usb_desc_other(const USBDescOther *desc, uint8_t *dest, size_t len)
 251{
 252    int bLength = desc->length ? desc->length : desc->data[0];
 253
 254    if (len < bLength) {
 255        return -1;
 256    }
 257
 258    memcpy(dest, desc->data, bLength);
 259    return bLength;
 260}
 261
 262static int usb_desc_cap_usb2_ext(const USBDesc *desc, uint8_t *dest, size_t len)
 263{
 264    uint8_t  bLength = 0x07;
 265    USBDescriptor *d = (void *)dest;
 266
 267    if (len < bLength) {
 268        return -1;
 269    }
 270
 271    d->bLength                          = bLength;
 272    d->bDescriptorType                  = USB_DT_DEVICE_CAPABILITY;
 273    d->u.cap.bDevCapabilityType         = USB_DEV_CAP_USB2_EXT;
 274
 275    d->u.cap.u.usb2_ext.bmAttributes_1  = (1 << 1);  /* LPM */
 276    d->u.cap.u.usb2_ext.bmAttributes_2  = 0;
 277    d->u.cap.u.usb2_ext.bmAttributes_3  = 0;
 278    d->u.cap.u.usb2_ext.bmAttributes_4  = 0;
 279
 280    return bLength;
 281}
 282
 283static int usb_desc_cap_super(const USBDesc *desc, uint8_t *dest, size_t len)
 284{
 285    uint8_t  bLength = 0x0a;
 286    USBDescriptor *d = (void *)dest;
 287
 288    if (len < bLength) {
 289        return -1;
 290    }
 291
 292    d->bLength                           = bLength;
 293    d->bDescriptorType                   = USB_DT_DEVICE_CAPABILITY;
 294    d->u.cap.bDevCapabilityType          = USB_DEV_CAP_SUPERSPEED;
 295
 296    d->u.cap.u.super.bmAttributes        = 0;
 297    d->u.cap.u.super.wSpeedsSupported_lo = 0;
 298    d->u.cap.u.super.wSpeedsSupported_hi = 0;
 299    d->u.cap.u.super.bFunctionalitySupport = 0;
 300    d->u.cap.u.super.bU1DevExitLat       = 0x0a;
 301    d->u.cap.u.super.wU2DevExitLat_lo    = 0x20;
 302    d->u.cap.u.super.wU2DevExitLat_hi    = 0;
 303
 304    if (desc->full) {
 305        d->u.cap.u.super.wSpeedsSupported_lo |= (1 << 1);
 306        d->u.cap.u.super.bFunctionalitySupport = 1;
 307    }
 308    if (desc->high) {
 309        d->u.cap.u.super.wSpeedsSupported_lo |= (1 << 2);
 310        if (!d->u.cap.u.super.bFunctionalitySupport) {
 311            d->u.cap.u.super.bFunctionalitySupport = 2;
 312        }
 313    }
 314    if (desc->super) {
 315        d->u.cap.u.super.wSpeedsSupported_lo |= (1 << 3);
 316        if (!d->u.cap.u.super.bFunctionalitySupport) {
 317            d->u.cap.u.super.bFunctionalitySupport = 3;
 318        }
 319    }
 320
 321    return bLength;
 322}
 323
 324static int usb_desc_bos(const USBDesc *desc, uint8_t *dest, size_t len)
 325{
 326    uint8_t  bLength = 0x05;
 327    uint16_t wTotalLength = 0;
 328    uint8_t  bNumDeviceCaps = 0;
 329    USBDescriptor *d = (void *)dest;
 330    int rc;
 331
 332    if (len < bLength) {
 333        return -1;
 334    }
 335
 336    d->bLength                      = bLength;
 337    d->bDescriptorType              = USB_DT_BOS;
 338
 339    wTotalLength += bLength;
 340
 341    if (desc->high != NULL) {
 342        rc = usb_desc_cap_usb2_ext(desc, dest + wTotalLength,
 343                                   len - wTotalLength);
 344        if (rc < 0) {
 345            return rc;
 346        }
 347        wTotalLength += rc;
 348        bNumDeviceCaps++;
 349    }
 350
 351    if (desc->super != NULL) {
 352        rc = usb_desc_cap_super(desc, dest + wTotalLength,
 353                                len - wTotalLength);
 354        if (rc < 0) {
 355            return rc;
 356        }
 357        wTotalLength += rc;
 358        bNumDeviceCaps++;
 359    }
 360
 361    d->u.bos.wTotalLength_lo = usb_lo(wTotalLength);
 362    d->u.bos.wTotalLength_hi = usb_hi(wTotalLength);
 363    d->u.bos.bNumDeviceCaps  = bNumDeviceCaps;
 364    return wTotalLength;
 365}
 366
 367/* ------------------------------------------------------------------ */
 368
 369static void usb_desc_ep_init(USBDevice *dev)
 370{
 371    const USBDescIface *iface;
 372    int i, e, pid, ep;
 373
 374    usb_ep_init(dev);
 375    for (i = 0; i < dev->ninterfaces; i++) {
 376        iface = dev->ifaces[i];
 377        if (iface == NULL) {
 378            continue;
 379        }
 380        for (e = 0; e < iface->bNumEndpoints; e++) {
 381            pid = (iface->eps[e].bEndpointAddress & USB_DIR_IN) ?
 382                USB_TOKEN_IN : USB_TOKEN_OUT;
 383            ep = iface->eps[e].bEndpointAddress & 0x0f;
 384            usb_ep_set_type(dev, pid, ep, iface->eps[e].bmAttributes & 0x03);
 385            usb_ep_set_ifnum(dev, pid, ep, iface->bInterfaceNumber);
 386            usb_ep_set_max_packet_size(dev, pid, ep,
 387                                       iface->eps[e].wMaxPacketSize);
 388        }
 389    }
 390}
 391
 392static const USBDescIface *usb_desc_find_interface(USBDevice *dev,
 393                                                   int nif, int alt)
 394{
 395    const USBDescIface *iface;
 396    int g, i;
 397
 398    if (!dev->config) {
 399        return NULL;
 400    }
 401    for (g = 0; g < dev->config->nif_groups; g++) {
 402        for (i = 0; i < dev->config->if_groups[g].nif; i++) {
 403            iface = &dev->config->if_groups[g].ifs[i];
 404            if (iface->bInterfaceNumber == nif &&
 405                iface->bAlternateSetting == alt) {
 406                return iface;
 407            }
 408        }
 409    }
 410    for (i = 0; i < dev->config->nif; i++) {
 411        iface = &dev->config->ifs[i];
 412        if (iface->bInterfaceNumber == nif &&
 413            iface->bAlternateSetting == alt) {
 414            return iface;
 415        }
 416    }
 417    return NULL;
 418}
 419
 420static int usb_desc_set_interface(USBDevice *dev, int index, int value)
 421{
 422    const USBDescIface *iface;
 423    int old;
 424
 425    iface = usb_desc_find_interface(dev, index, value);
 426    if (iface == NULL) {
 427        return -1;
 428    }
 429
 430    old = dev->altsetting[index];
 431    dev->altsetting[index] = value;
 432    dev->ifaces[index] = iface;
 433    usb_desc_ep_init(dev);
 434
 435    if (old != value) {
 436        usb_device_set_interface(dev, index, old, value);
 437    }
 438    return 0;
 439}
 440
 441static int usb_desc_set_config(USBDevice *dev, int value)
 442{
 443    int i;
 444
 445    if (value == 0) {
 446        dev->configuration = 0;
 447        dev->ninterfaces   = 0;
 448        dev->config = NULL;
 449    } else {
 450        for (i = 0; i < dev->device->bNumConfigurations; i++) {
 451            if (dev->device->confs[i].bConfigurationValue == value) {
 452                dev->configuration = value;
 453                dev->ninterfaces   = dev->device->confs[i].bNumInterfaces;
 454                dev->config = dev->device->confs + i;
 455                assert(dev->ninterfaces <= USB_MAX_INTERFACES);
 456            }
 457        }
 458        if (i < dev->device->bNumConfigurations) {
 459            return -1;
 460        }
 461    }
 462
 463    for (i = 0; i < dev->ninterfaces; i++) {
 464        usb_desc_set_interface(dev, i, 0);
 465    }
 466    for (; i < USB_MAX_INTERFACES; i++) {
 467        dev->altsetting[i] = 0;
 468        dev->ifaces[i] = NULL;
 469    }
 470
 471    return 0;
 472}
 473
 474static void usb_desc_setdefaults(USBDevice *dev)
 475{
 476    const USBDesc *desc = usb_device_get_usb_desc(dev);
 477
 478    assert(desc != NULL);
 479    switch (dev->speed) {
 480    case USB_SPEED_LOW:
 481    case USB_SPEED_FULL:
 482        dev->device = desc->full;
 483        break;
 484    case USB_SPEED_HIGH:
 485        dev->device = desc->high;
 486        break;
 487    case USB_SPEED_SUPER:
 488        dev->device = desc->super;
 489        break;
 490    }
 491    usb_desc_set_config(dev, 0);
 492}
 493
 494void usb_desc_init(USBDevice *dev)
 495{
 496    const USBDesc *desc = usb_device_get_usb_desc(dev);
 497
 498    assert(desc != NULL);
 499    dev->speed = USB_SPEED_FULL;
 500    dev->speedmask = 0;
 501    if (desc->full) {
 502        dev->speedmask |= USB_SPEED_MASK_FULL;
 503    }
 504    if (desc->high) {
 505        dev->speedmask |= USB_SPEED_MASK_HIGH;
 506    }
 507    if (desc->super) {
 508        dev->speedmask |= USB_SPEED_MASK_SUPER;
 509    }
 510    usb_desc_setdefaults(dev);
 511}
 512
 513void usb_desc_attach(USBDevice *dev)
 514{
 515    const USBDesc *desc = usb_device_get_usb_desc(dev);
 516
 517    assert(desc != NULL);
 518    if (desc->super && (dev->port->speedmask & USB_SPEED_MASK_SUPER)) {
 519        dev->speed = USB_SPEED_SUPER;
 520    } else if (desc->high && (dev->port->speedmask & USB_SPEED_MASK_HIGH)) {
 521        dev->speed = USB_SPEED_HIGH;
 522    } else if (desc->full && (dev->port->speedmask & USB_SPEED_MASK_FULL)) {
 523        dev->speed = USB_SPEED_FULL;
 524    } else {
 525        return;
 526    }
 527    usb_desc_setdefaults(dev);
 528}
 529
 530void usb_desc_set_string(USBDevice *dev, uint8_t index, const char *str)
 531{
 532    USBDescString *s;
 533
 534    QLIST_FOREACH(s, &dev->strings, next) {
 535        if (s->index == index) {
 536            break;
 537        }
 538    }
 539    if (s == NULL) {
 540        s = g_malloc0(sizeof(*s));
 541        s->index = index;
 542        QLIST_INSERT_HEAD(&dev->strings, s, next);
 543    }
 544    g_free(s->str);
 545    s->str = g_strdup(str);
 546}
 547
 548/*
 549 * This function creates a serial number for a usb device.
 550 * The serial number should:
 551 *   (a) Be unique within the virtual machine.
 552 *   (b) Be constant, so you don't get a new one each
 553 *       time the guest is started.
 554 * So we are using the physical location to generate a serial number
 555 * from it.  It has three pieces:  First a fixed, device-specific
 556 * prefix.  Second the device path of the host controller (which is
 557 * the pci address in most cases).  Third the physical port path.
 558 * Results in serial numbers like this: "314159-0000:00:1d.7-3".
 559 */
 560void usb_desc_create_serial(USBDevice *dev)
 561{
 562    DeviceState *hcd = dev->qdev.parent_bus->parent;
 563    const USBDesc *desc = usb_device_get_usb_desc(dev);
 564    int index = desc->id.iSerialNumber;
 565    char serial[64];
 566    char *path;
 567    int dst;
 568
 569    if (dev->serial) {
 570        /* 'serial' usb bus property has priority if present */
 571        usb_desc_set_string(dev, index, dev->serial);
 572        return;
 573    }
 574
 575    assert(index != 0 && desc->str[index] != NULL);
 576    dst = snprintf(serial, sizeof(serial), "%s", desc->str[index]);
 577    path = qdev_get_dev_path(hcd);
 578    if (path) {
 579        dst += snprintf(serial+dst, sizeof(serial)-dst, "-%s", path);
 580    }
 581    dst += snprintf(serial+dst, sizeof(serial)-dst, "-%s", dev->port->path);
 582    usb_desc_set_string(dev, index, serial);
 583}
 584
 585const char *usb_desc_get_string(USBDevice *dev, uint8_t index)
 586{
 587    USBDescString *s;
 588
 589    QLIST_FOREACH(s, &dev->strings, next) {
 590        if (s->index == index) {
 591            return s->str;
 592        }
 593    }
 594    return NULL;
 595}
 596
 597int usb_desc_string(USBDevice *dev, int index, uint8_t *dest, size_t len)
 598{
 599    uint8_t bLength, pos, i;
 600    const char *str;
 601
 602    if (len < 4) {
 603        return -1;
 604    }
 605
 606    if (index == 0) {
 607        /* language ids */
 608        dest[0] = 4;
 609        dest[1] = USB_DT_STRING;
 610        dest[2] = 0x09;
 611        dest[3] = 0x04;
 612        return 4;
 613    }
 614
 615    str = usb_desc_get_string(dev, index);
 616    if (str == NULL) {
 617        str = usb_device_get_usb_desc(dev)->str[index];
 618        if (str == NULL) {
 619            return 0;
 620        }
 621    }
 622
 623    bLength = strlen(str) * 2 + 2;
 624    dest[0] = bLength;
 625    dest[1] = USB_DT_STRING;
 626    i = 0; pos = 2;
 627    while (pos+1 < bLength && pos+1 < len) {
 628        dest[pos++] = str[i++];
 629        dest[pos++] = 0;
 630    }
 631    return pos;
 632}
 633
 634int usb_desc_get_descriptor(USBDevice *dev, USBPacket *p,
 635                            int value, uint8_t *dest, size_t len)
 636{
 637    const USBDesc *desc = usb_device_get_usb_desc(dev);
 638    const USBDescDevice *other_dev;
 639    uint8_t buf[256];
 640    uint8_t type = value >> 8;
 641    uint8_t index = value & 0xff;
 642    int flags, ret = -1;
 643
 644    if (dev->speed == USB_SPEED_HIGH) {
 645        other_dev = usb_device_get_usb_desc(dev)->full;
 646    } else {
 647        other_dev = usb_device_get_usb_desc(dev)->high;
 648    }
 649
 650    flags = 0;
 651    if (dev->device->bcdUSB >= 0x0300) {
 652        flags |= USB_DESC_FLAG_SUPER;
 653    }
 654
 655    switch(type) {
 656    case USB_DT_DEVICE:
 657        ret = usb_desc_device(&desc->id, dev->device, buf, sizeof(buf));
 658        trace_usb_desc_device(dev->addr, len, ret);
 659        break;
 660    case USB_DT_CONFIG:
 661        if (index < dev->device->bNumConfigurations) {
 662            ret = usb_desc_config(dev->device->confs + index, flags,
 663                                  buf, sizeof(buf));
 664        }
 665        trace_usb_desc_config(dev->addr, index, len, ret);
 666        break;
 667    case USB_DT_STRING:
 668        ret = usb_desc_string(dev, index, buf, sizeof(buf));
 669        trace_usb_desc_string(dev->addr, index, len, ret);
 670        break;
 671    case USB_DT_DEVICE_QUALIFIER:
 672        if (other_dev != NULL) {
 673            ret = usb_desc_device_qualifier(other_dev, buf, sizeof(buf));
 674        }
 675        trace_usb_desc_device_qualifier(dev->addr, len, ret);
 676        break;
 677    case USB_DT_OTHER_SPEED_CONFIG:
 678        if (other_dev != NULL && index < other_dev->bNumConfigurations) {
 679            ret = usb_desc_config(other_dev->confs + index, flags,
 680                                  buf, sizeof(buf));
 681            buf[0x01] = USB_DT_OTHER_SPEED_CONFIG;
 682        }
 683        trace_usb_desc_other_speed_config(dev->addr, index, len, ret);
 684        break;
 685    case USB_DT_BOS:
 686        ret = usb_desc_bos(desc, buf, sizeof(buf));
 687        trace_usb_desc_bos(dev->addr, len, ret);
 688        break;
 689
 690    case USB_DT_DEBUG:
 691        /* ignore silently */
 692        break;
 693
 694    default:
 695        fprintf(stderr, "%s: %d unknown type %d (len %zd)\n", __FUNCTION__,
 696                dev->addr, type, len);
 697        break;
 698    }
 699
 700    if (ret > 0) {
 701        if (ret > len) {
 702            ret = len;
 703        }
 704        memcpy(dest, buf, ret);
 705        p->actual_length = ret;
 706        ret = 0;
 707    }
 708    return ret;
 709}
 710
 711int usb_desc_handle_control(USBDevice *dev, USBPacket *p,
 712        int request, int value, int index, int length, uint8_t *data)
 713{
 714    const USBDesc *desc = usb_device_get_usb_desc(dev);
 715    int ret = -1;
 716
 717    assert(desc != NULL);
 718    switch(request) {
 719    case DeviceOutRequest | USB_REQ_SET_ADDRESS:
 720        dev->addr = value;
 721        trace_usb_set_addr(dev->addr);
 722        ret = 0;
 723        break;
 724
 725    case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
 726        ret = usb_desc_get_descriptor(dev, p, value, data, length);
 727        break;
 728
 729    case DeviceRequest | USB_REQ_GET_CONFIGURATION:
 730        /*
 731         * 9.4.2: 0 should be returned if the device is unconfigured, otherwise
 732         * the non zero value of bConfigurationValue.
 733         */
 734        data[0] = dev->config ? dev->config->bConfigurationValue : 0;
 735        p->actual_length = 1;
 736        ret = 0;
 737        break;
 738    case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
 739        ret = usb_desc_set_config(dev, value);
 740        trace_usb_set_config(dev->addr, value, ret);
 741        break;
 742
 743    case DeviceRequest | USB_REQ_GET_STATUS: {
 744        const USBDescConfig *config = dev->config ?
 745            dev->config : &dev->device->confs[0];
 746
 747        data[0] = 0;
 748        /*
 749         * Default state: Device behavior when this request is received while
 750         *                the device is in the Default state is not specified.
 751         * We return the same value that a configured device would return if
 752         * it used the first configuration.
 753         */
 754        if (config->bmAttributes & 0x40) {
 755            data[0] |= 1 << USB_DEVICE_SELF_POWERED;
 756        }
 757        if (dev->remote_wakeup) {
 758            data[0] |= 1 << USB_DEVICE_REMOTE_WAKEUP;
 759        }
 760        data[1] = 0x00;
 761        p->actual_length = 2;
 762        ret = 0;
 763        break;
 764    }
 765    case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
 766        if (value == USB_DEVICE_REMOTE_WAKEUP) {
 767            dev->remote_wakeup = 0;
 768            ret = 0;
 769        }
 770        trace_usb_clear_device_feature(dev->addr, value, ret);
 771        break;
 772    case DeviceOutRequest | USB_REQ_SET_FEATURE:
 773        if (value == USB_DEVICE_REMOTE_WAKEUP) {
 774            dev->remote_wakeup = 1;
 775            ret = 0;
 776        }
 777        trace_usb_set_device_feature(dev->addr, value, ret);
 778        break;
 779
 780    case InterfaceRequest | USB_REQ_GET_INTERFACE:
 781        if (index < 0 || index >= dev->ninterfaces) {
 782            break;
 783        }
 784        data[0] = dev->altsetting[index];
 785        p->actual_length = 1;
 786        ret = 0;
 787        break;
 788    case InterfaceOutRequest | USB_REQ_SET_INTERFACE:
 789        ret = usb_desc_set_interface(dev, index, value);
 790        trace_usb_set_interface(dev->addr, index, value, ret);
 791        break;
 792
 793    }
 794    return ret;
 795}
 796