libusb/os/netbsd_usb.c

   1 /*
   2  * Copyright © 2011 Martin Pieuchot <mpi@openbsd.org>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 #include <config.h>
  20
  21 #include <sys/time.h>
  22 #include <sys/types.h>
  23
  24 #include <errno.h>
  25 #include <fcntl.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <unistd.h>
  30
  31 #include <dev/usb/usb.h>
  32
  33 #include "libusbi.h"
  34
  35 struct device_priv {
  36         char devnode[16];
  37         int fd;
  38
  39         unsigned char *cdesc;                   /* active config descriptor */
  40         usb_device_descriptor_t ddesc;          /* usb device descriptor */
  41 };
  42
  43 struct handle_priv {
  44         int endpoints[USB_MAX_ENDPOINTS];
  45 };
  46
  47 /*
  48  * Backend functions
  49  */
  50 static int netbsd_get_device_list(struct libusb_context *,
  51     struct discovered_devs **);
  52 static int netbsd_open(struct libusb_device_handle *);
  53 static void netbsd_close(struct libusb_device_handle *);
  54
  55 static int netbsd_get_device_descriptor(struct libusb_device *, unsigned char *,
  56     int *);
  57 static int netbsd_get_active_config_descriptor(struct libusb_device *,
  58     unsigned char *, size_t, int *);
  59 static int netbsd_get_config_descriptor(struct libusb_device *, uint8_t,
  60     unsigned char *, size_t, int *);
  61
  62 static int netbsd_get_configuration(struct libusb_device_handle *, int *);
  63 static int netbsd_set_configuration(struct libusb_device_handle *, int);
  64
  65 static int netbsd_claim_interface(struct libusb_device_handle *, int);
  66 static int netbsd_release_interface(struct libusb_device_handle *, int);
  67
  68 static int netbsd_set_interface_altsetting(struct libusb_device_handle *, int,
  69     int);
  70 static int netbsd_clear_halt(struct libusb_device_handle *, unsigned char);
  71 static int netbsd_reset_device(struct libusb_device_handle *);
  72 static void netbsd_destroy_device(struct libusb_device *);
  73
  74 static int netbsd_submit_transfer(struct usbi_transfer *);
  75 static int netbsd_cancel_transfer(struct usbi_transfer *);
  76 static void netbsd_clear_transfer_priv(struct usbi_transfer *);
  77 static int netbsd_handle_transfer_completion(struct usbi_transfer *);
  78 static int netbsd_clock_gettime(int, struct timespec *);
  79
  80 /*
  81  * Private functions
  82  */
  83 static int _errno_to_libusb(int);
  84 static int _cache_active_config_descriptor(struct libusb_device *, int);
  85 static int _sync_control_transfer(struct usbi_transfer *);
  86 static int _sync_gen_transfer(struct usbi_transfer *);
  87 static int _access_endpoint(struct libusb_transfer *);
  88
  89 const struct usbi_os_backend usbi_backend = {
  90         "Synchronous NetBSD backend",
  91         0,
  92         NULL,                           /* init() */
  93         NULL,                           /* exit() */
  94         NULL,                           /* set_option() */
  95         netbsd_get_device_list,
  96         NULL,                           /* hotplug_poll */
  97         netbsd_open,
  98         netbsd_close,
  99
 100         netbsd_get_device_descriptor,
 101         netbsd_get_active_config_descriptor,
 102         netbsd_get_config_descriptor,
 103         NULL,                           /* get_config_descriptor_by_value() */
 104
 105         netbsd_get_configuration,
 106         netbsd_set_configuration,
 107
 108         netbsd_claim_interface,
 109         netbsd_release_interface,
 110
 111         netbsd_set_interface_altsetting,
 112         netbsd_clear_halt,
 113         netbsd_reset_device,
 114
 115         NULL,                           /* alloc_streams */
 116         NULL,                           /* free_streams */
 117
 118         NULL,                           /* dev_mem_alloc() */
 119         NULL,                           /* dev_mem_free() */
 120
 121         NULL,                           /* kernel_driver_active() */
 122         NULL,                           /* detach_kernel_driver() */
 123         NULL,                           /* attach_kernel_driver() */
 124
 125         netbsd_destroy_device,
 126
 127         netbsd_submit_transfer,
 128         netbsd_cancel_transfer,
 129         netbsd_clear_transfer_priv,
 130
 131         NULL,                           /* handle_events() */
 132         netbsd_handle_transfer_completion,
 133
 134         netbsd_clock_gettime,
 135         0,                              /* context_priv_size */
 136         sizeof(struct device_priv),
 137         sizeof(struct handle_priv),
 138         0,                              /* transfer_priv_size */
 139 };
 140
 141 int
 142 netbsd_get_device_list(struct libusb_context * ctx,
 143         struct discovered_devs **discdevs)
 144 {
 145         struct libusb_device *dev;
 146         struct device_priv *dpriv;
 147         struct usb_device_info di;
 148         unsigned long session_id;
 149         char devnode[16];
 150         int fd, err, i;
 151
 152         usbi_dbg("");
 153
 154         /* Only ugen(4) is supported */
 155         for (i = 0; i < USB_MAX_DEVICES; i++) {
 156                 /* Control endpoint is always .00 */
 157                 snprintf(devnode, sizeof(devnode), "/dev/ugen%d.00", i);
 158
 159                 if ((fd = open(devnode, O_RDONLY)) < 0) {
 160                         if (errno != ENOENT && errno != ENXIO)
 161                                 usbi_err(ctx, "could not open %s", devnode);
 162                         continue;
 163                 }
 164
 165                 if (ioctl(fd, USB_GET_DEVICEINFO, &di) < 0)
 166                         continue;
 167
 168                 session_id = (di.udi_bus << 8 | di.udi_addr);
 169                 dev = usbi_get_device_by_session_id(ctx, session_id);
 170
 171                 if (dev == NULL) {
 172                         dev = usbi_alloc_device(ctx, session_id);
 173                         if (dev == NULL)
 174                                 return (LIBUSB_ERROR_NO_MEM);
 175
 176                         dev->bus_number = di.udi_bus;
 177                         dev->device_address = di.udi_addr;
 178                         dev->speed = di.udi_speed;
 179
 180                         dpriv = (struct device_priv *)dev->os_priv;
 181                         strlcpy(dpriv->devnode, devnode, sizeof(devnode));
 182                         dpriv->fd = -1;
 183
 184                         if (ioctl(fd, USB_GET_DEVICE_DESC, &dpriv->ddesc) < 0) {
 185                                 err = errno;
 186                                 goto error;
 187                         }
 188
 189                         dpriv->cdesc = NULL;
 190                         if (_cache_active_config_descriptor(dev, fd)) {
 191                                 err = errno;
 192                                 goto error;
 193                         }
 194
 195                         if ((err = usbi_sanitize_device(dev)))
 196                                 goto error;
 197                 }
 198                 close(fd);
 199
 200                 if (discovered_devs_append(*discdevs, dev) == NULL)
 201                         return (LIBUSB_ERROR_NO_MEM);
 202
 203                 libusb_unref_device(dev);
 204         }
 205
 206         return (LIBUSB_SUCCESS);
 207
 208 error:
 209         close(fd);
 210         libusb_unref_device(dev);
 211         return _errno_to_libusb(err);
 212 }
 213
 214 int
 215 netbsd_open(struct libusb_device_handle *handle)
 216 {
 217         struct device_priv *dpriv = (struct device_priv *)handle->dev->os_priv;
 218         struct handle_priv *hpriv = (struct handle_priv *)handle->os_priv;
 219         int i;
 220
 221         dpriv->fd = open(dpriv->devnode, O_RDWR);
 222         if (dpriv->fd < 0) {
 223                 dpriv->fd = open(dpriv->devnode, O_RDONLY);
 224                 if (dpriv->fd < 0)
 225                         return _errno_to_libusb(errno);
 226         }
 227
 228         for (i = 0; i < USB_MAX_ENDPOINTS; i++)
 229                 hpriv->endpoints[i] = -1;
 230
 231         usbi_dbg("open %s: fd %d", dpriv->devnode, dpriv->fd);
 232
 233         return (LIBUSB_SUCCESS);
 234 }
 235
 236 void
 237 netbsd_close(struct libusb_device_handle *handle)
 238 {
 239         struct device_priv *dpriv = (struct device_priv *)handle->dev->os_priv;
 240
 241         usbi_dbg("close: fd %d", dpriv->fd);
 242
 243         close(dpriv->fd);
 244         dpriv->fd = -1;
 245 }
 246
 247 int
 248 netbsd_get_device_descriptor(struct libusb_device *dev, unsigned char *buf,
 249     int *host_endian)
 250 {
 251         struct device_priv *dpriv = (struct device_priv *)dev->os_priv;
 252
 253         usbi_dbg("");
 254
 255         memcpy(buf, &dpriv->ddesc, DEVICE_DESC_LENGTH);
 256
 257         *host_endian = 0;
 258
 259         return (LIBUSB_SUCCESS);
 260 }
 261
 262 int
 263 netbsd_get_active_config_descriptor(struct libusb_device *dev,
 264     unsigned char *buf, size_t len, int *host_endian)
 265 {
 266         struct device_priv *dpriv = (struct device_priv *)dev->os_priv;
 267         usb_config_descriptor_t *ucd;
 268
 269         ucd = (usb_config_descriptor_t *) dpriv->cdesc;
 270         len = MIN(len, UGETW(ucd->wTotalLength));
 271
 272         usbi_dbg("len %d", len);
 273
 274         memcpy(buf, dpriv->cdesc, len);
 275
 276         *host_endian = 0;
 277
 278         return len;
 279 }
 280
 281 int
 282 netbsd_get_config_descriptor(struct libusb_device *dev, uint8_t idx,
 283     unsigned char *buf, size_t len, int *host_endian)
 284 {
 285         struct device_priv *dpriv = (struct device_priv *)dev->os_priv;
 286         struct usb_full_desc ufd;
 287         int fd, err;
 288
 289         usbi_dbg("index %d, len %d", idx, len);
 290
 291         /* A config descriptor may be requested before opening the device */
 292         if (dpriv->fd >= 0) {
 293                 fd = dpriv->fd;
 294         } else {
 295                 fd = open(dpriv->devnode, O_RDONLY);
 296                 if (fd < 0)
 297                         return _errno_to_libusb(errno);
 298         }
 299
 300         ufd.ufd_config_index = idx;
 301         ufd.ufd_size = len;
 302         ufd.ufd_data = buf;
 303
 304         if ((ioctl(fd, USB_GET_FULL_DESC, &ufd)) < 0) {
 305                 err = errno;
 306                 if (dpriv->fd < 0)
 307                         close(fd);
 308                 return _errno_to_libusb(err);
 309         }
 310
 311         if (dpriv->fd < 0)
 312                 close(fd);
 313
 314         *host_endian = 0;
 315
 316         return len;
 317 }
 318
 319 int
 320 netbsd_get_configuration(struct libusb_device_handle *handle, int *config)
 321 {
 322         struct device_priv *dpriv = (struct device_priv *)handle->dev->os_priv;
 323
 324         usbi_dbg("");
 325
 326         if (ioctl(dpriv->fd, USB_GET_CONFIG, config) < 0)
 327                 return _errno_to_libusb(errno);
 328
 329         usbi_dbg("configuration %d", *config);
 330
 331         return (LIBUSB_SUCCESS);
 332 }
 333
 334 int
 335 netbsd_set_configuration(struct libusb_device_handle *handle, int config)
 336 {
 337         struct device_priv *dpriv = (struct device_priv *)handle->dev->os_priv;
 338
 339         usbi_dbg("configuration %d", config);
 340
 341         if (ioctl(dpriv->fd, USB_SET_CONFIG, &config) < 0)
 342                 return _errno_to_libusb(errno);
 343
 344         return _cache_active_config_descriptor(handle->dev, dpriv->fd);
 345 }
 346
 347 int
 348 netbsd_claim_interface(struct libusb_device_handle *handle, int iface)
 349 {
 350         struct handle_priv *hpriv = (struct handle_priv *)handle->os_priv;
 351         int i;
 352
 353         for (i = 0; i < USB_MAX_ENDPOINTS; i++)
 354                 hpriv->endpoints[i] = -1;
 355
 356         return (LIBUSB_SUCCESS);
 357 }
 358
 359 int
 360 netbsd_release_interface(struct libusb_device_handle *handle, int iface)
 361 {
 362         struct handle_priv *hpriv = (struct handle_priv *)handle->os_priv;
 363         int i;
 364
 365         for (i = 0; i < USB_MAX_ENDPOINTS; i++)
 366                 if (hpriv->endpoints[i] >= 0)
 367                         close(hpriv->endpoints[i]);
 368
 369         return (LIBUSB_SUCCESS);
 370 }
 371
 372 int
 373 netbsd_set_interface_altsetting(struct libusb_device_handle *handle, int iface,
 374     int altsetting)
 375 {
 376         struct device_priv *dpriv = (struct device_priv *)handle->dev->os_priv;
 377         struct usb_alt_interface intf;
 378
 379         usbi_dbg("iface %d, setting %d", iface, altsetting);
 380
 381         memset(&intf, 0, sizeof(intf));
 382
 383         intf.uai_interface_index = iface;
 384         intf.uai_alt_no = altsetting;
 385
 386         if (ioctl(dpriv->fd, USB_SET_ALTINTERFACE, &intf) < 0)
 387                 return _errno_to_libusb(errno);
 388
 389         return (LIBUSB_SUCCESS);
 390 }
 391
 392 int
 393 netbsd_clear_halt(struct libusb_device_handle *handle, unsigned char endpoint)
 394 {
 395         struct device_priv *dpriv = (struct device_priv *)handle->dev->os_priv;
 396         struct usb_ctl_request req;
 397
 398         usbi_dbg("");
 399
 400         req.ucr_request.bmRequestType = UT_WRITE_ENDPOINT;
 401         req.ucr_request.bRequest = UR_CLEAR_FEATURE;
 402         USETW(req.ucr_request.wValue, UF_ENDPOINT_HALT);
 403         USETW(req.ucr_request.wIndex, endpoint);
 404         USETW(req.ucr_request.wLength, 0);
 405
 406         if (ioctl(dpriv->fd, USB_DO_REQUEST, &req) < 0)
 407                 return _errno_to_libusb(errno);
 408
 409         return (LIBUSB_SUCCESS);
 410 }
 411
 412 int
 413 netbsd_reset_device(struct libusb_device_handle *handle)
 414 {
 415         usbi_dbg("");
 416
 417         return (LIBUSB_ERROR_NOT_SUPPORTED);
 418 }
 419
 420 void
 421 netbsd_destroy_device(struct libusb_device *dev)
 422 {
 423         struct device_priv *dpriv = (struct device_priv *)dev->os_priv;
 424
 425         usbi_dbg("");
 426
 427         free(dpriv->cdesc);
 428 }
 429
 430 int
 431 netbsd_submit_transfer(struct usbi_transfer *itransfer)
 432 {
 433         struct libusb_transfer *transfer;
 434         struct handle_priv *hpriv;
 435         int err = 0;
 436
 437         usbi_dbg("");
 438
 439         transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
 440         hpriv = (struct handle_priv *)transfer->dev_handle->os_priv;
 441
 442         switch (transfer->type) {
 443         case LIBUSB_TRANSFER_TYPE_CONTROL:
 444                 err = _sync_control_transfer(itransfer);
 445                 break;
 446         case LIBUSB_TRANSFER_TYPE_ISOCHRONOUS:
 447                 if (IS_XFEROUT(transfer)) {
 448                         /* Isochronous write is not supported */
 449                         err = LIBUSB_ERROR_NOT_SUPPORTED;
 450                         break;
 451                 }
 452                 err = _sync_gen_transfer(itransfer);
 453                 break;
 454         case LIBUSB_TRANSFER_TYPE_BULK:
 455         case LIBUSB_TRANSFER_TYPE_INTERRUPT:
 456                 if (IS_XFEROUT(transfer) &&
 457                     transfer->flags & LIBUSB_TRANSFER_ADD_ZERO_PACKET) {
 458                         err = LIBUSB_ERROR_NOT_SUPPORTED;
 459                         break;
 460                 }
 461                 err = _sync_gen_transfer(itransfer);
 462                 break;
 463         case LIBUSB_TRANSFER_TYPE_BULK_STREAM:
 464                 err = LIBUSB_ERROR_NOT_SUPPORTED;
 465                 break;
 466         }
 467
 468         if (err)
 469                 return (err);
 470
 471         usbi_signal_transfer_completion(itransfer);
 472
 473         return (LIBUSB_SUCCESS);
 474 }
 475
 476 int
 477 netbsd_cancel_transfer(struct usbi_transfer *itransfer)
 478 {
 479         usbi_dbg("");
 480
 481         return (LIBUSB_ERROR_NOT_SUPPORTED);
 482 }
 483
 484 void
 485 netbsd_clear_transfer_priv(struct usbi_transfer *itransfer)
 486 {
 487         usbi_dbg("");
 488
 489         /* Nothing to do */
 490 }
 491
 492 int
 493 netbsd_handle_transfer_completion(struct usbi_transfer *itransfer)
 494 {
 495         return usbi_handle_transfer_completion(itransfer, LIBUSB_TRANSFER_COMPLETED);
 496 }
 497
 498 int
 499 netbsd_clock_gettime(int clkid, struct timespec *tp)
 500 {
 501         usbi_dbg("clock %d", clkid);
 502
 503         if (clkid == USBI_CLOCK_REALTIME)
 504                 return clock_gettime(CLOCK_REALTIME, tp);
 505
 506         if (clkid == USBI_CLOCK_MONOTONIC)
 507                 return clock_gettime(CLOCK_MONOTONIC, tp);
 508
 509         return (LIBUSB_ERROR_INVALID_PARAM);
 510 }
 511
 512 int
 513 _errno_to_libusb(int err)
 514 {
 515         switch (err) {
 516         case EIO:
 517                 return (LIBUSB_ERROR_IO);
 518         case EACCES:
 519                 return (LIBUSB_ERROR_ACCESS);
 520         case ENOENT:
 521                 return (LIBUSB_ERROR_NO_DEVICE);
 522         case ENOMEM:
 523                 return (LIBUSB_ERROR_NO_MEM);
 524         }
 525
 526         usbi_dbg("error: %s", strerror(err));
 527
 528         return (LIBUSB_ERROR_OTHER);
 529 }
 530
 531 int
 532 _cache_active_config_descriptor(struct libusb_device *dev, int fd)
 533 {
 534         struct device_priv *dpriv = (struct device_priv *)dev->os_priv;
 535         struct usb_config_desc ucd;
 536         struct usb_full_desc ufd;
 537         unsigned char* buf;
 538         int len;
 539
 540         usbi_dbg("fd %d", fd);
 541
 542         ucd.ucd_config_index = USB_CURRENT_CONFIG_INDEX;
 543
 544         if ((ioctl(fd, USB_GET_CONFIG_DESC, &ucd)) < 0)
 545                 return _errno_to_libusb(errno);
 546
 547         usbi_dbg("active bLength %d", ucd.ucd_desc.bLength);
 548
 549         len = UGETW(ucd.ucd_desc.wTotalLength);
 550         buf = malloc(len);
 551         if (buf == NULL)
 552                 return (LIBUSB_ERROR_NO_MEM);
 553
 554         ufd.ufd_config_index = ucd.ucd_config_index;
 555         ufd.ufd_size = len;
 556         ufd.ufd_data = buf;
 557
 558         usbi_dbg("index %d, len %d", ufd.ufd_config_index, len);
 559
 560         if ((ioctl(fd, USB_GET_FULL_DESC, &ufd)) < 0) {
 561                 free(buf);
 562                 return _errno_to_libusb(errno);
 563         }
 564
 565         if (dpriv->cdesc)
 566                 free(dpriv->cdesc);
 567         dpriv->cdesc = buf;
 568
 569         return (0);
 570 }
 571
 572 int
 573 _sync_control_transfer(struct usbi_transfer *itransfer)
 574 {
 575         struct libusb_transfer *transfer;
 576         struct libusb_control_setup *setup;
 577         struct device_priv *dpriv;
 578         struct usb_ctl_request req;
 579
 580         transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
 581         dpriv = (struct device_priv *)transfer->dev_handle->dev->os_priv;
 582         setup = (struct libusb_control_setup *)transfer->buffer;
 583
 584         usbi_dbg("type %d request %d value %d index %d length %d timeout %d",
 585             setup->bmRequestType, setup->bRequest,
 586             libusb_le16_to_cpu(setup->wValue),
 587             libusb_le16_to_cpu(setup->wIndex),
 588             libusb_le16_to_cpu(setup->wLength), transfer->timeout);
 589
 590         req.ucr_request.bmRequestType = setup->bmRequestType;
 591         req.ucr_request.bRequest = setup->bRequest;
 592         /* Don't use USETW, libusb already deals with the endianness */
 593         (*(uint16_t *)req.ucr_request.wValue) = setup->wValue;
 594         (*(uint16_t *)req.ucr_request.wIndex) = setup->wIndex;
 595         (*(uint16_t *)req.ucr_request.wLength) = setup->wLength;
 596         req.ucr_data = transfer->buffer + LIBUSB_CONTROL_SETUP_SIZE;
 597
 598         if ((transfer->flags & LIBUSB_TRANSFER_SHORT_NOT_OK) == 0)
 599                 req.ucr_flags = USBD_SHORT_XFER_OK;
 600
 601         if ((ioctl(dpriv->fd, USB_SET_TIMEOUT, &transfer->timeout)) < 0)
 602                 return _errno_to_libusb(errno);
 603
 604         if ((ioctl(dpriv->fd, USB_DO_REQUEST, &req)) < 0)
 605                 return _errno_to_libusb(errno);
 606
 607         itransfer->transferred = req.ucr_actlen;
 608
 609         usbi_dbg("transferred %d", itransfer->transferred);
 610
 611         return (0);
 612 }
 613
 614 int
 615 _access_endpoint(struct libusb_transfer *transfer)
 616 {
 617         struct handle_priv *hpriv;
 618         struct device_priv *dpriv;
 619         char *s, devnode[16];
 620         int fd, endpt;
 621         mode_t mode;
 622
 623         hpriv = (struct handle_priv *)transfer->dev_handle->os_priv;
 624         dpriv = (struct device_priv *)transfer->dev_handle->dev->os_priv;
 625
 626         endpt = UE_GET_ADDR(transfer->endpoint);
 627         mode = IS_XFERIN(transfer) ? O_RDONLY : O_WRONLY;
 628
 629         usbi_dbg("endpoint %d mode %d", endpt, mode);
 630
 631         if (hpriv->endpoints[endpt] < 0) {
 632                 /* Pick the right node given the control one */
 633                 strlcpy(devnode, dpriv->devnode, sizeof(devnode));
 634                 s = strchr(devnode, '.');
 635                 snprintf(s, 4, ".%02d", endpt);
 636
 637                 /* We may need to read/write to the same endpoint later. */
 638                 if (((fd = open(devnode, O_RDWR)) < 0) && (errno == ENXIO))
 639                         if ((fd = open(devnode, mode)) < 0)
 640                                 return (-1);
 641
 642                 hpriv->endpoints[endpt] = fd;
 643         }
 644
 645         return (hpriv->endpoints[endpt]);
 646 }
 647
 648 int
 649 _sync_gen_transfer(struct usbi_transfer *itransfer)
 650 {
 651         struct libusb_transfer *transfer;
 652         int fd, nr = 1;
 653
 654         transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer);
 655
 656         /*
 657          * Bulk, Interrupt or Isochronous transfer depends on the
 658          * endpoint and thus the node to open.
 659          */
 660         if ((fd = _access_endpoint(transfer)) < 0)
 661                 return _errno_to_libusb(errno);
 662
 663         if ((ioctl(fd, USB_SET_TIMEOUT, &transfer->timeout)) < 0)
 664                 return _errno_to_libusb(errno);
 665
 666         if (IS_XFERIN(transfer)) {
 667                 if ((transfer->flags & LIBUSB_TRANSFER_SHORT_NOT_OK) == 0)
 668                         if ((ioctl(fd, USB_SET_SHORT_XFER, &nr)) < 0)
 669                                 return _errno_to_libusb(errno);
 670
 671                 nr = read(fd, transfer->buffer, transfer->length);
 672         } else {
 673                 nr = write(fd, transfer->buffer, transfer->length);
 674         }
 675
 676         if (nr < 0)
 677                 return _errno_to_libusb(errno);
 678
 679         itransfer->transferred = nr;
 680
 681         return (0);
 682 }