drivers/usb/host/usb-uclass.c

   1 /*
   2  * (C) Copyright 2015 Google, Inc
   3  * Written by Simon Glass <sjg@chromium.org>
   4  *
   5  * usb_match_device() modified from Linux kernel v4.0.
   6  *
   7  * SPDX-License-Identifier:     GPL-2.0+
   8  */
   9
  10 #include <common.h>
  11 #include <dm.h>
  12 #include <errno.h>
  13 #include <memalign.h>
  14 #include <usb.h>
  15 #include <dm/device-internal.h>
  16 #include <dm/lists.h>
  17 #include <dm/root.h>
  18 #include <dm/uclass-internal.h>
  19
  20 DECLARE_GLOBAL_DATA_PTR;
  21
  22 extern bool usb_started; /* flag for the started/stopped USB status */
  23 static bool asynch_allowed;
  24
  25 struct usb_uclass_priv {
  26         int companion_device_count;
  27 };
  28
  29 int usb_disable_asynch(int disable)
  30 {
  31         int old_value = asynch_allowed;
  32
  33         asynch_allowed = !disable;
  34         return old_value;
  35 }
  36
  37 int submit_int_msg(struct usb_device *udev, unsigned long pipe, void *buffer,
  38                    int length, int interval)
  39 {
  40         struct udevice *bus = udev->controller_dev;
  41         struct dm_usb_ops *ops = usb_get_ops(bus);
  42
  43         if (!ops->interrupt)
  44                 return -ENOSYS;
  45
  46         return ops->interrupt(bus, udev, pipe, buffer, length, interval);
  47 }
  48
  49 int submit_control_msg(struct usb_device *udev, unsigned long pipe,
  50                        void *buffer, int length, struct devrequest *setup)
  51 {
  52         struct udevice *bus = udev->controller_dev;
  53         struct dm_usb_ops *ops = usb_get_ops(bus);
  54         struct usb_uclass_priv *uc_priv = bus->uclass->priv;
  55         int err;
  56
  57         if (!ops->control)
  58                 return -ENOSYS;
  59
  60         err = ops->control(bus, udev, pipe, buffer, length, setup);
  61         if (setup->request == USB_REQ_SET_FEATURE &&
  62             setup->requesttype == USB_RT_PORT &&
  63             setup->value == cpu_to_le16(USB_PORT_FEAT_RESET) &&
  64             err == -ENXIO) {
  65                 /* Device handed over to companion after port reset */
  66                 uc_priv->companion_device_count++;
  67         }
  68
  69         return err;
  70 }
  71
  72 int submit_bulk_msg(struct usb_device *udev, unsigned long pipe, void *buffer,
  73                     int length)
  74 {
  75         struct udevice *bus = udev->controller_dev;
  76         struct dm_usb_ops *ops = usb_get_ops(bus);
  77
  78         if (!ops->bulk)
  79                 return -ENOSYS;
  80
  81         return ops->bulk(bus, udev, pipe, buffer, length);
  82 }
  83
  84 struct int_queue *create_int_queue(struct usb_device *udev,
  85                 unsigned long pipe, int queuesize, int elementsize,
  86                 void *buffer, int interval)
  87 {
  88         struct udevice *bus = udev->controller_dev;
  89         struct dm_usb_ops *ops = usb_get_ops(bus);
  90
  91         if (!ops->create_int_queue)
  92                 return NULL;
  93
  94         return ops->create_int_queue(bus, udev, pipe, queuesize, elementsize,
  95                                      buffer, interval);
  96 }
  97
  98 void *poll_int_queue(struct usb_device *udev, struct int_queue *queue)
  99 {
 100         struct udevice *bus = udev->controller_dev;
 101         struct dm_usb_ops *ops = usb_get_ops(bus);
 102
 103         if (!ops->poll_int_queue)
 104                 return NULL;
 105
 106         return ops->poll_int_queue(bus, udev, queue);
 107 }
 108
 109 int destroy_int_queue(struct usb_device *udev, struct int_queue *queue)
 110 {
 111         struct udevice *bus = udev->controller_dev;
 112         struct dm_usb_ops *ops = usb_get_ops(bus);
 113
 114         if (!ops->destroy_int_queue)
 115                 return -ENOSYS;
 116
 117         return ops->destroy_int_queue(bus, udev, queue);
 118 }
 119
 120 int usb_alloc_device(struct usb_device *udev)
 121 {
 122         struct udevice *bus = udev->controller_dev;
 123         struct dm_usb_ops *ops = usb_get_ops(bus);
 124
 125         /* This is only requird by some controllers - current XHCI */
 126         if (!ops->alloc_device)
 127                 return 0;
 128
 129         return ops->alloc_device(bus, udev);
 130 }
 131
 132 int usb_reset_root_port(struct usb_device *udev)
 133 {
 134         struct udevice *bus = udev->controller_dev;
 135         struct dm_usb_ops *ops = usb_get_ops(bus);
 136
 137         if (!ops->reset_root_port)
 138                 return -ENOSYS;
 139
 140         return ops->reset_root_port(bus, udev);
 141 }
 142
 143 int usb_stop(void)
 144 {
 145         struct udevice *bus;
 146         struct uclass *uc;
 147         struct usb_uclass_priv *uc_priv;
 148         int err = 0, ret;
 149
 150         /* De-activate any devices that have been activated */
 151         ret = uclass_get(UCLASS_USB, &uc);
 152         if (ret)
 153                 return ret;
 154
 155         uc_priv = uc->priv;
 156
 157         uclass_foreach_dev(bus, uc) {
 158                 ret = device_remove(bus);
 159                 if (ret && !err)
 160                         err = ret;
 161         }
 162
 163 #ifdef CONFIG_SANDBOX
 164         struct udevice *dev;
 165
 166         /* Reset all enulation devices */
 167         ret = uclass_get(UCLASS_USB_EMUL, &uc);
 168         if (ret)
 169                 return ret;
 170
 171         uclass_foreach_dev(dev, uc)
 172                 usb_emul_reset(dev);
 173 #endif
 174 #ifdef CONFIG_USB_STORAGE
 175         usb_stor_reset();
 176 #endif
 177         usb_hub_reset();
 178         uc_priv->companion_device_count = 0;
 179         usb_started = 0;
 180
 181         return err;
 182 }
 183
 184 static void usb_scan_bus(struct udevice *bus, bool recurse)
 185 {
 186         struct usb_bus_priv *priv;
 187         struct udevice *dev;
 188         int ret;
 189
 190         priv = dev_get_uclass_priv(bus);
 191
 192         assert(recurse);        /* TODO: Support non-recusive */
 193
 194         printf("scanning bus %d for devices... ", bus->seq);
 195         debug("\n");
 196         ret = usb_scan_device(bus, 0, USB_SPEED_FULL, &dev);
 197         if (ret)
 198                 printf("failed, error %d\n", ret);
 199         else if (priv->next_addr == 0)
 200                 printf("No USB Device found\n");
 201         else
 202                 printf("%d USB Device(s) found\n", priv->next_addr);
 203 }
 204
 205 static void remove_inactive_children(struct uclass *uc, struct udevice *bus)
 206 {
 207         uclass_foreach_dev(bus, uc) {
 208                 struct udevice *dev, *next;
 209
 210                 if (!device_active(bus))
 211                         continue;
 212                 device_foreach_child_safe(dev, next, bus) {
 213                         if (!device_active(dev))
 214                                 device_unbind(dev);
 215                 }
 216         }
 217 }
 218
 219 int usb_init(void)
 220 {
 221         int controllers_initialized = 0;
 222         struct usb_uclass_priv *uc_priv;
 223         struct usb_bus_priv *priv;
 224         struct udevice *bus;
 225         struct uclass *uc;
 226         int count = 0;
 227         int ret;
 228
 229         asynch_allowed = 1;
 230         usb_hub_reset();
 231
 232         ret = uclass_get(UCLASS_USB, &uc);
 233         if (ret)
 234                 return ret;
 235
 236         uc_priv = uc->priv;
 237
 238         uclass_foreach_dev(bus, uc) {
 239                 /* init low_level USB */
 240                 printf("USB%d:   ", count);
 241                 count++;
 242                 ret = device_probe(bus);
 243                 if (ret == -ENODEV) {   /* No such device. */
 244                         puts("Port not available.\n");
 245                         controllers_initialized++;
 246                         continue;
 247                 }
 248
 249                 if (ret) {              /* Other error. */
 250                         printf("probe failed, error %d\n", ret);
 251                         continue;
 252                 }
 253                 controllers_initialized++;
 254                 usb_started = true;
 255         }
 256
 257         /*
 258          * lowlevel init done, now scan the bus for devices i.e. search HUBs
 259          * and configure them, first scan primary controllers.
 260          */
 261         uclass_foreach_dev(bus, uc) {
 262                 if (!device_active(bus))
 263                         continue;
 264
 265                 priv = dev_get_uclass_priv(bus);
 266                 if (!priv->companion)
 267                         usb_scan_bus(bus, true);
 268         }
 269
 270         /*
 271          * Now that the primary controllers have been scanned and have handed
 272          * over any devices they do not understand to their companions, scan
 273          * the companions if necessary.
 274          */
 275         if (uc_priv->companion_device_count) {
 276                 uclass_foreach_dev(bus, uc) {
 277                         if (!device_active(bus))
 278                                 continue;
 279
 280                         priv = dev_get_uclass_priv(bus);
 281                         if (priv->companion)
 282                                 usb_scan_bus(bus, true);
 283                 }
 284         }
 285
 286         debug("scan end\n");
 287
 288         /* Remove any devices that were not found on this scan */
 289         remove_inactive_children(uc, bus);
 290
 291         ret = uclass_get(UCLASS_USB_HUB, &uc);
 292         if (ret)
 293                 return ret;
 294         remove_inactive_children(uc, bus);
 295
 296         /* if we were not able to find at least one working bus, bail out */
 297         if (!count)
 298                 printf("No controllers found\n");
 299         else if (controllers_initialized == 0)
 300                 printf("USB error: all controllers failed lowlevel init\n");
 301
 302         return usb_started ? 0 : -1;
 303 }
 304
 305 /*
 306  * TODO(sjg@chromium.org): Remove this legacy function. At present it is needed
 307  * to support boards which use driver model for USB but not Ethernet, and want
 308  * to use USB Ethernet.
 309  *
 310  * The #if clause is here to ensure that remains the only case.
 311  */
 312 #if !defined(CONFIG_DM_ETH) && defined(CONFIG_USB_HOST_ETHER)
 313 static struct usb_device *find_child_devnum(struct udevice *parent, int devnum)
 314 {
 315         struct usb_device *udev;
 316         struct udevice *dev;
 317
 318         if (!device_active(parent))
 319                 return NULL;
 320         udev = dev_get_parent_priv(parent);
 321         if (udev->devnum == devnum)
 322                 return udev;
 323
 324         for (device_find_first_child(parent, &dev);
 325              dev;
 326              device_find_next_child(&dev)) {
 327                 udev = find_child_devnum(dev, devnum);
 328                 if (udev)
 329                         return udev;
 330         }
 331
 332         return NULL;
 333 }
 334
 335 struct usb_device *usb_get_dev_index(struct udevice *bus, int index)
 336 {
 337         struct udevice *dev;
 338         int devnum = index + 1; /* Addresses are allocated from 1 on USB */
 339
 340         device_find_first_child(bus, &dev);
 341         if (!dev)
 342                 return NULL;
 343
 344         return find_child_devnum(dev, devnum);
 345 }
 346 #endif
 347
 348 int usb_post_bind(struct udevice *dev)
 349 {
 350         /* Scan the bus for devices */
 351         return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
 352 }
 353
 354 int usb_setup_ehci_gadget(struct ehci_ctrl **ctlrp)
 355 {
 356         struct usb_platdata *plat;
 357         struct udevice *dev;
 358         int ret;
 359
 360         /* Find the old device and remove it */
 361         ret = uclass_find_device_by_seq(UCLASS_USB, 0, true, &dev);
 362         if (ret)
 363                 return ret;
 364         ret = device_remove(dev);
 365         if (ret)
 366                 return ret;
 367
 368         plat = dev_get_platdata(dev);
 369         plat->init_type = USB_INIT_DEVICE;
 370         ret = device_probe(dev);
 371         if (ret)
 372                 return ret;
 373         *ctlrp = dev_get_priv(dev);
 374
 375         return 0;
 376 }
 377
 378 /* returns 0 if no match, 1 if match */
 379 int usb_match_device(const struct usb_device_descriptor *desc,
 380                      const struct usb_device_id *id)
 381 {
 382         if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
 383             id->idVendor != le16_to_cpu(desc->idVendor))
 384                 return 0;
 385
 386         if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
 387             id->idProduct != le16_to_cpu(desc->idProduct))
 388                 return 0;
 389
 390         /* No need to test id->bcdDevice_lo != 0, since 0 is never
 391            greater than any unsigned number. */
 392         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
 393             (id->bcdDevice_lo > le16_to_cpu(desc->bcdDevice)))
 394                 return 0;
 395
 396         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
 397             (id->bcdDevice_hi < le16_to_cpu(desc->bcdDevice)))
 398                 return 0;
 399
 400         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
 401             (id->bDeviceClass != desc->bDeviceClass))
 402                 return 0;
 403
 404         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
 405             (id->bDeviceSubClass != desc->bDeviceSubClass))
 406                 return 0;
 407
 408         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
 409             (id->bDeviceProtocol != desc->bDeviceProtocol))
 410                 return 0;
 411
 412         return 1;
 413 }
 414
 415 /* returns 0 if no match, 1 if match */
 416 int usb_match_one_id_intf(const struct usb_device_descriptor *desc,
 417                           const struct usb_interface_descriptor *int_desc,
 418                           const struct usb_device_id *id)
 419 {
 420         /* The interface class, subclass, protocol and number should never be
 421          * checked for a match if the device class is Vendor Specific,
 422          * unless the match record specifies the Vendor ID. */
 423         if (desc->bDeviceClass == USB_CLASS_VENDOR_SPEC &&
 424             !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
 425             (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
 426                                 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
 427                                 USB_DEVICE_ID_MATCH_INT_PROTOCOL |
 428                                 USB_DEVICE_ID_MATCH_INT_NUMBER)))
 429                 return 0;
 430
 431         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
 432             (id->bInterfaceClass != int_desc->bInterfaceClass))
 433                 return 0;
 434
 435         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
 436             (id->bInterfaceSubClass != int_desc->bInterfaceSubClass))
 437                 return 0;
 438
 439         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
 440             (id->bInterfaceProtocol != int_desc->bInterfaceProtocol))
 441                 return 0;
 442
 443         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) &&
 444             (id->bInterfaceNumber != int_desc->bInterfaceNumber))
 445                 return 0;
 446
 447         return 1;
 448 }
 449
 450 /* returns 0 if no match, 1 if match */
 451 int usb_match_one_id(struct usb_device_descriptor *desc,
 452                      struct usb_interface_descriptor *int_desc,
 453                      const struct usb_device_id *id)
 454 {
 455         if (!usb_match_device(desc, id))
 456                 return 0;
 457
 458         return usb_match_one_id_intf(desc, int_desc, id);
 459 }
 460
 461 /**
 462  * usb_find_and_bind_driver() - Find and bind the right USB driver
 463  *
 464  * This only looks at certain fields in the descriptor.
 465  */
 466 static int usb_find_and_bind_driver(struct udevice *parent,
 467                                     struct usb_device_descriptor *desc,
 468                                     struct usb_interface_descriptor *iface,
 469                                     int bus_seq, int devnum,
 470                                     struct udevice **devp)
 471 {
 472         struct usb_driver_entry *start, *entry;
 473         int n_ents;
 474         int ret;
 475         char name[30], *str;
 476
 477         *devp = NULL;
 478         debug("%s: Searching for driver\n", __func__);
 479         start = ll_entry_start(struct usb_driver_entry, usb_driver_entry);
 480         n_ents = ll_entry_count(struct usb_driver_entry, usb_driver_entry);
 481         for (entry = start; entry != start + n_ents; entry++) {
 482                 const struct usb_device_id *id;
 483                 struct udevice *dev;
 484                 const struct driver *drv;
 485                 struct usb_dev_platdata *plat;
 486
 487                 for (id = entry->match; id->match_flags; id++) {
 488                         if (!usb_match_one_id(desc, iface, id))
 489                                 continue;
 490
 491                         drv = entry->driver;
 492                         /*
 493                          * We could pass the descriptor to the driver as
 494                          * platdata (instead of NULL) and allow its bind()
 495                          * method to return -ENOENT if it doesn't support this
 496                          * device. That way we could continue the search to
 497                          * find another driver. For now this doesn't seem
 498                          * necesssary, so just bind the first match.
 499                          */
 500                         ret = device_bind(parent, drv, drv->name, NULL, -1,
 501                                           &dev);
 502                         if (ret)
 503                                 goto error;
 504                         debug("%s: Match found: %s\n", __func__, drv->name);
 505                         dev->driver_data = id->driver_info;
 506                         plat = dev_get_parent_platdata(dev);
 507                         plat->id = *id;
 508                         *devp = dev;
 509                         return 0;
 510                 }
 511         }
 512
 513         /* Bind a generic driver so that the device can be used */
 514         snprintf(name, sizeof(name), "generic_bus_%x_dev_%x", bus_seq, devnum);
 515         str = strdup(name);
 516         if (!str)
 517                 return -ENOMEM;
 518         ret = device_bind_driver(parent, "usb_dev_generic_drv", str, devp);
 519
 520 error:
 521         debug("%s: No match found: %d\n", __func__, ret);
 522         return ret;
 523 }
 524
 525 /**
 526  * usb_find_child() - Find an existing device which matches our needs
 527  *
 528  *
 529  */
 530 static int usb_find_child(struct udevice *parent,
 531                           struct usb_device_descriptor *desc,
 532                           struct usb_interface_descriptor *iface,
 533                           struct udevice **devp)
 534 {
 535         struct udevice *dev;
 536
 537         *devp = NULL;
 538         for (device_find_first_child(parent, &dev);
 539              dev;
 540              device_find_next_child(&dev)) {
 541                 struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
 542
 543                 /* If this device is already in use, skip it */
 544                 if (device_active(dev))
 545                         continue;
 546                 debug("   %s: name='%s', plat=%d, desc=%d\n", __func__,
 547                       dev->name, plat->id.bDeviceClass, desc->bDeviceClass);
 548                 if (usb_match_one_id(desc, iface, &plat->id)) {
 549                         *devp = dev;
 550                         return 0;
 551                 }
 552         }
 553
 554         return -ENOENT;
 555 }
 556
 557 int usb_scan_device(struct udevice *parent, int port,
 558                     enum usb_device_speed speed, struct udevice **devp)
 559 {
 560         struct udevice *dev;
 561         bool created = false;
 562         struct usb_dev_platdata *plat;
 563         struct usb_bus_priv *priv;
 564         struct usb_device *parent_udev;
 565         int ret;
 566         ALLOC_CACHE_ALIGN_BUFFER(struct usb_device, udev, 1);
 567         struct usb_interface_descriptor *iface = &udev->config.if_desc[0].desc;
 568
 569         *devp = NULL;
 570         memset(udev, '\0', sizeof(*udev));
 571         udev->controller_dev = usb_get_bus(parent);
 572         priv = dev_get_uclass_priv(udev->controller_dev);
 573
 574         /*
 575          * Somewhat nasty, this. We create a local device and use the normal
 576          * USB stack to read its descriptor. Then we know what type of device
 577          * to create for real.
 578          *
 579          * udev->dev is set to the parent, since we don't have a real device
 580          * yet. The USB stack should not access udev.dev anyway, except perhaps
 581          * to find the controller, and the controller will either be @parent,
 582          * or some parent of @parent.
 583          *
 584          * Another option might be to create the device as a generic USB
 585          * device, then morph it into the correct one when we know what it
 586          * should be. This means that a generic USB device would morph into
 587          * a network controller, or a USB flash stick, for example. However,
 588          * we don't support such morphing and it isn't clear that it would
 589          * be easy to do.
 590          *
 591          * Yet another option is to split out the USB stack parts of udev
 592          * into something like a 'struct urb' (as Linux does) which can exist
 593          * independently of any device. This feels cleaner, but calls for quite
 594          * a big change to the USB stack.
 595          *
 596          * For now, the approach is to set up an empty udev, read its
 597          * descriptor and assign it an address, then bind a real device and
 598          * stash the resulting information into the device's parent
 599          * platform data. Then when we probe it, usb_child_pre_probe() is called
 600          * and it will pull the information out of the stash.
 601          */
 602         udev->dev = parent;
 603         udev->speed = speed;
 604         udev->devnum = priv->next_addr + 1;
 605         udev->portnr = port;
 606         debug("Calling usb_setup_device(), portnr=%d\n", udev->portnr);
 607         parent_udev = device_get_uclass_id(parent) == UCLASS_USB_HUB ?
 608                 dev_get_parent_priv(parent) : NULL;
 609         ret = usb_setup_device(udev, priv->desc_before_addr, parent_udev);
 610         debug("read_descriptor for '%s': ret=%d\n", parent->name, ret);
 611         if (ret)
 612                 return ret;
 613         ret = usb_find_child(parent, &udev->descriptor, iface, &dev);
 614         debug("** usb_find_child returns %d\n", ret);
 615         if (ret) {
 616                 if (ret != -ENOENT)
 617                         return ret;
 618                 ret = usb_find_and_bind_driver(parent, &udev->descriptor, iface,
 619                                                udev->controller_dev->seq,
 620                                                udev->devnum, &dev);
 621                 if (ret)
 622                         return ret;
 623                 created = true;
 624         }
 625         plat = dev_get_parent_platdata(dev);
 626         debug("%s: Probing '%s', plat=%p\n", __func__, dev->name, plat);
 627         plat->devnum = udev->devnum;
 628         plat->udev = udev;
 629         priv->next_addr++;
 630         ret = device_probe(dev);
 631         if (ret) {
 632                 debug("%s: Device '%s' probe failed\n", __func__, dev->name);
 633                 priv->next_addr--;
 634                 if (created)
 635                         device_unbind(dev);
 636                 return ret;
 637         }
 638         *devp = dev;
 639
 640         return 0;
 641 }
 642
 643 /*
 644  * Detect if a USB device has been plugged or unplugged.
 645  */
 646 int usb_detect_change(void)
 647 {
 648         struct udevice *hub;
 649         struct uclass *uc;
 650         int change = 0;
 651         int ret;
 652
 653         ret = uclass_get(UCLASS_USB_HUB, &uc);
 654         if (ret)
 655                 return ret;
 656
 657         uclass_foreach_dev(hub, uc) {
 658                 struct usb_device *udev;
 659                 struct udevice *dev;
 660
 661                 if (!device_active(hub))
 662                         continue;
 663                 for (device_find_first_child(hub, &dev);
 664                      dev;
 665                      device_find_next_child(&dev)) {
 666                         struct usb_port_status status;
 667
 668                         if (!device_active(dev))
 669                                 continue;
 670
 671                         udev = dev_get_parent_priv(dev);
 672                         if (usb_get_port_status(udev, udev->portnr, &status)
 673                                         < 0)
 674                                 /* USB request failed */
 675                                 continue;
 676
 677                         if (le16_to_cpu(status.wPortChange) &
 678                             USB_PORT_STAT_C_CONNECTION)
 679                                 change++;
 680                 }
 681         }
 682
 683         return change;
 684 }
 685
 686 int usb_child_post_bind(struct udevice *dev)
 687 {
 688         struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
 689         const void *blob = gd->fdt_blob;
 690         int val;
 691
 692         if (dev->of_offset == -1)
 693                 return 0;
 694
 695         /* We only support matching a few things */
 696         val = fdtdec_get_int(blob, dev->of_offset, "usb,device-class", -1);
 697         if (val != -1) {
 698                 plat->id.match_flags |= USB_DEVICE_ID_MATCH_DEV_CLASS;
 699                 plat->id.bDeviceClass = val;
 700         }
 701         val = fdtdec_get_int(blob, dev->of_offset, "usb,interface-class", -1);
 702         if (val != -1) {
 703                 plat->id.match_flags |= USB_DEVICE_ID_MATCH_INT_CLASS;
 704                 plat->id.bInterfaceClass = val;
 705         }
 706
 707         return 0;
 708 }
 709
 710 struct udevice *usb_get_bus(struct udevice *dev)
 711 {
 712         struct udevice *bus;
 713
 714         for (bus = dev; bus && device_get_uclass_id(bus) != UCLASS_USB; )
 715                 bus = bus->parent;
 716         if (!bus) {
 717                 /* By design this cannot happen */
 718                 assert(bus);
 719                 debug("USB HUB '%s' does not have a controller\n", dev->name);
 720         }
 721
 722         return bus;
 723 }
 724
 725 int usb_child_pre_probe(struct udevice *dev)
 726 {
 727         struct usb_device *udev = dev_get_parent_priv(dev);
 728         struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
 729         int ret;
 730
 731         if (plat->udev) {
 732                 /*
 733                  * Copy over all the values set in the on stack struct
 734                  * usb_device in usb_scan_device() to our final struct
 735                  * usb_device for this dev.
 736                  */
 737                 *udev = *(plat->udev);
 738                 /* And clear plat->udev as it will not be valid for long */
 739                 plat->udev = NULL;
 740                 udev->dev = dev;
 741         } else {
 742                 /*
 743                  * This happens with devices which are explicitly bound
 744                  * instead of being discovered through usb_scan_device()
 745                  * such as sandbox emul devices.
 746                  */
 747                 udev->dev = dev;
 748                 udev->controller_dev = usb_get_bus(dev);
 749                 udev->devnum = plat->devnum;
 750
 751                 /*
 752                  * udev did not go through usb_scan_device(), so we need to
 753                  * select the config and read the config descriptors.
 754                  */
 755                 ret = usb_select_config(udev);
 756                 if (ret)
 757                         return ret;
 758         }
 759
 760         return 0;
 761 }
 762
 763 UCLASS_DRIVER(usb) = {
 764         .id             = UCLASS_USB,
 765         .name           = "usb",
 766         .flags          = DM_UC_FLAG_SEQ_ALIAS,
 767         .post_bind      = usb_post_bind,
 768         .priv_auto_alloc_size = sizeof(struct usb_uclass_priv),
 769         .per_child_auto_alloc_size = sizeof(struct usb_device),
 770         .per_device_auto_alloc_size = sizeof(struct usb_bus_priv),
 771         .child_post_bind = usb_child_post_bind,
 772         .child_pre_probe = usb_child_pre_probe,
 773         .per_child_platdata_auto_alloc_size = sizeof(struct usb_dev_platdata),
 774 };
 775
 776 UCLASS_DRIVER(usb_dev_generic) = {
 777         .id             = UCLASS_USB_DEV_GENERIC,
 778         .name           = "usb_dev_generic",
 779 };
 780
 781 U_BOOT_DRIVER(usb_dev_generic_drv) = {
 782         .id             = UCLASS_USB_DEV_GENERIC,
 783         .name           = "usb_dev_generic_drv",
 784 };