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/uclass-internal.h>
  18
  19 DECLARE_GLOBAL_DATA_PTR;
  20
  21 extern bool usb_started; /* flag for the started/stopped USB status */
  22 static bool asynch_allowed;
  23
  24 struct usb_uclass_priv {
  25         int companion_device_count;
  26 };
  27
  28 int usb_disable_asynch(int disable)
  29 {
  30         int old_value = asynch_allowed;
  31
  32         asynch_allowed = !disable;
  33         return old_value;
  34 }
  35
  36 int submit_int_msg(struct usb_device *udev, unsigned long pipe, void *buffer,
  37                    int length, int interval)
  38 {
  39         struct udevice *bus = udev->controller_dev;
  40         struct dm_usb_ops *ops = usb_get_ops(bus);
  41
  42         if (!ops->interrupt)
  43                 return -ENOSYS;
  44
  45         return ops->interrupt(bus, udev, pipe, buffer, length, interval);
  46 }
  47
  48 int submit_control_msg(struct usb_device *udev, unsigned long pipe,
  49                        void *buffer, int length, struct devrequest *setup)
  50 {
  51         struct udevice *bus = udev->controller_dev;
  52         struct dm_usb_ops *ops = usb_get_ops(bus);
  53         struct usb_uclass_priv *uc_priv = bus->uclass->priv;
  54         int err;
  55
  56         if (!ops->control)
  57                 return -ENOSYS;
  58
  59         err = ops->control(bus, udev, pipe, buffer, length, setup);
  60         if (setup->request == USB_REQ_SET_FEATURE &&
  61             setup->requesttype == USB_RT_PORT &&
  62             setup->value == cpu_to_le16(USB_PORT_FEAT_RESET) &&
  63             err == -ENXIO) {
  64                 /* Device handed over to companion after port reset */
  65                 uc_priv->companion_device_count++;
  66         }
  67
  68         return err;
  69 }
  70
  71 int submit_bulk_msg(struct usb_device *udev, unsigned long pipe, void *buffer,
  72                     int length)
  73 {
  74         struct udevice *bus = udev->controller_dev;
  75         struct dm_usb_ops *ops = usb_get_ops(bus);
  76
  77         if (!ops->bulk)
  78                 return -ENOSYS;
  79
  80         return ops->bulk(bus, udev, pipe, buffer, length);
  81 }
  82
  83 struct int_queue *create_int_queue(struct usb_device *udev,
  84                 unsigned long pipe, int queuesize, int elementsize,
  85                 void *buffer, int interval)
  86 {
  87         struct udevice *bus = udev->controller_dev;
  88         struct dm_usb_ops *ops = usb_get_ops(bus);
  89
  90         if (!ops->create_int_queue)
  91                 return NULL;
  92
  93         return ops->create_int_queue(bus, udev, pipe, queuesize, elementsize,
  94                                      buffer, interval);
  95 }
  96
  97 void *poll_int_queue(struct usb_device *udev, struct int_queue *queue)
  98 {
  99         struct udevice *bus = udev->controller_dev;
 100         struct dm_usb_ops *ops = usb_get_ops(bus);
 101
 102         if (!ops->poll_int_queue)
 103                 return NULL;
 104
 105         return ops->poll_int_queue(bus, udev, queue);
 106 }
 107
 108 int destroy_int_queue(struct usb_device *udev, struct int_queue *queue)
 109 {
 110         struct udevice *bus = udev->controller_dev;
 111         struct dm_usb_ops *ops = usb_get_ops(bus);
 112
 113         if (!ops->destroy_int_queue)
 114                 return -ENOSYS;
 115
 116         return ops->destroy_int_queue(bus, udev, queue);
 117 }
 118
 119 int usb_alloc_device(struct usb_device *udev)
 120 {
 121         struct udevice *bus = udev->controller_dev;
 122         struct dm_usb_ops *ops = usb_get_ops(bus);
 123
 124         /* This is only requird by some controllers - current XHCI */
 125         if (!ops->alloc_device)
 126                 return 0;
 127
 128         return ops->alloc_device(bus, udev);
 129 }
 130
 131 int usb_reset_root_port(struct usb_device *udev)
 132 {
 133         struct udevice *bus = udev->controller_dev;
 134         struct dm_usb_ops *ops = usb_get_ops(bus);
 135
 136         if (!ops->reset_root_port)
 137                 return -ENOSYS;
 138
 139         return ops->reset_root_port(bus, udev);
 140 }
 141
 142 int usb_stop(void)
 143 {
 144         struct udevice *bus;
 145         struct uclass *uc;
 146         struct usb_uclass_priv *uc_priv;
 147         int err = 0, ret;
 148
 149         /* De-activate any devices that have been activated */
 150         ret = uclass_get(UCLASS_USB, &uc);
 151         if (ret)
 152                 return ret;
 153
 154         uc_priv = uc->priv;
 155
 156         uclass_foreach_dev(bus, uc) {
 157                 ret = device_remove(bus);
 158                 if (ret && !err)
 159                         err = ret;
 160         }
 161 #ifdef CONFIG_BLK
 162         ret = blk_unbind_all(IF_TYPE_USB);
 163         if (ret && !err)
 164                 err = ret;
 165 #endif
 166 #ifdef CONFIG_SANDBOX
 167         struct udevice *dev;
 168
 169         /* Reset all enulation devices */
 170         ret = uclass_get(UCLASS_USB_EMUL, &uc);
 171         if (ret)
 172                 return ret;
 173
 174         uclass_foreach_dev(dev, uc)
 175                 usb_emul_reset(dev);
 176 #endif
 177 #ifdef CONFIG_USB_STORAGE
 178         usb_stor_reset();
 179 #endif
 180         usb_hub_reset();
 181         uc_priv->companion_device_count = 0;
 182         usb_started = 0;
 183
 184         return err;
 185 }
 186
 187 static void usb_scan_bus(struct udevice *bus, bool recurse)
 188 {
 189         struct usb_bus_priv *priv;
 190         struct udevice *dev;
 191         int ret;
 192
 193         priv = dev_get_uclass_priv(bus);
 194
 195         assert(recurse);        /* TODO: Support non-recusive */
 196
 197         printf("scanning bus %d for devices... ", bus->seq);
 198         debug("\n");
 199         ret = usb_scan_device(bus, 0, USB_SPEED_FULL, &dev);
 200         if (ret)
 201                 printf("failed, error %d\n", ret);
 202         else if (priv->next_addr == 0)
 203                 printf("No USB Device found\n");
 204         else
 205                 printf("%d USB Device(s) found\n", priv->next_addr);
 206 }
 207
 208 static void remove_inactive_children(struct uclass *uc, struct udevice *bus)
 209 {
 210         uclass_foreach_dev(bus, uc) {
 211                 struct udevice *dev, *next;
 212
 213                 if (!device_active(bus))
 214                         continue;
 215                 device_foreach_child_safe(dev, next, bus) {
 216                         if (!device_active(dev))
 217                                 device_unbind(dev);
 218                 }
 219         }
 220 }
 221
 222 int usb_init(void)
 223 {
 224         int controllers_initialized = 0;
 225         struct usb_uclass_priv *uc_priv;
 226         struct usb_bus_priv *priv;
 227         struct udevice *bus;
 228         struct uclass *uc;
 229         int count = 0;
 230         int ret;
 231
 232         asynch_allowed = 1;
 233         usb_hub_reset();
 234
 235         ret = uclass_get(UCLASS_USB, &uc);
 236         if (ret)
 237                 return ret;
 238
 239         uc_priv = uc->priv;
 240
 241         uclass_foreach_dev(bus, uc) {
 242                 /* init low_level USB */
 243                 printf("USB%d:   ", count);
 244                 count++;
 245                 ret = device_probe(bus);
 246                 if (ret == -ENODEV) {   /* No such device. */
 247                         puts("Port not available.\n");
 248                         controllers_initialized++;
 249                         continue;
 250                 }
 251
 252                 if (ret) {              /* Other error. */
 253                         printf("probe failed, error %d\n", ret);
 254                         continue;
 255                 }
 256                 controllers_initialized++;
 257                 usb_started = true;
 258         }
 259
 260         /*
 261          * lowlevel init done, now scan the bus for devices i.e. search HUBs
 262          * and configure them, first scan primary controllers.
 263          */
 264         uclass_foreach_dev(bus, uc) {
 265                 if (!device_active(bus))
 266                         continue;
 267
 268                 priv = dev_get_uclass_priv(bus);
 269                 if (!priv->companion)
 270                         usb_scan_bus(bus, true);
 271         }
 272
 273         /*
 274          * Now that the primary controllers have been scanned and have handed
 275          * over any devices they do not understand to their companions, scan
 276          * the companions if necessary.
 277          */
 278         if (uc_priv->companion_device_count) {
 279                 uclass_foreach_dev(bus, uc) {
 280                         if (!device_active(bus))
 281                                 continue;
 282
 283                         priv = dev_get_uclass_priv(bus);
 284                         if (priv->companion)
 285                                 usb_scan_bus(bus, true);
 286                 }
 287         }
 288
 289         debug("scan end\n");
 290
 291         /* Remove any devices that were not found on this scan */
 292         remove_inactive_children(uc, bus);
 293
 294         ret = uclass_get(UCLASS_USB_HUB, &uc);
 295         if (ret)
 296                 return ret;
 297         remove_inactive_children(uc, bus);
 298
 299         /* if we were not able to find at least one working bus, bail out */
 300         if (!count)
 301                 printf("No controllers found\n");
 302         else if (controllers_initialized == 0)
 303                 printf("USB error: all controllers failed lowlevel init\n");
 304
 305         return usb_started ? 0 : -1;
 306 }
 307
 308 /*
 309  * TODO(sjg@chromium.org): Remove this legacy function. At present it is needed
 310  * to support boards which use driver model for USB but not Ethernet, and want
 311  * to use USB Ethernet.
 312  *
 313  * The #if clause is here to ensure that remains the only case.
 314  */
 315 #if !defined(CONFIG_DM_ETH) && defined(CONFIG_USB_HOST_ETHER)
 316 static struct usb_device *find_child_devnum(struct udevice *parent, int devnum)
 317 {
 318         struct usb_device *udev;
 319         struct udevice *dev;
 320
 321         if (!device_active(parent))
 322                 return NULL;
 323         udev = dev_get_parent_priv(parent);
 324         if (udev->devnum == devnum)
 325                 return udev;
 326
 327         for (device_find_first_child(parent, &dev);
 328              dev;
 329              device_find_next_child(&dev)) {
 330                 udev = find_child_devnum(dev, devnum);
 331                 if (udev)
 332                         return udev;
 333         }
 334
 335         return NULL;
 336 }
 337
 338 struct usb_device *usb_get_dev_index(struct udevice *bus, int index)
 339 {
 340         struct udevice *dev;
 341         int devnum = index + 1; /* Addresses are allocated from 1 on USB */
 342
 343         device_find_first_child(bus, &dev);
 344         if (!dev)
 345                 return NULL;
 346
 347         return find_child_devnum(dev, devnum);
 348 }
 349 #endif
 350
 351 int usb_post_bind(struct udevice *dev)
 352 {
 353         return dm_scan_fdt_dev(dev);
 354 }
 355
 356 int usb_setup_ehci_gadget(struct ehci_ctrl **ctlrp)
 357 {
 358         struct usb_platdata *plat;
 359         struct udevice *dev;
 360         int ret;
 361
 362         /* Find the old device and remove it */
 363         ret = uclass_find_device_by_seq(UCLASS_USB, 0, true, &dev);
 364         if (ret)
 365                 return ret;
 366         ret = device_remove(dev);
 367         if (ret)
 368                 return ret;
 369
 370         plat = dev_get_platdata(dev);
 371         plat->init_type = USB_INIT_DEVICE;
 372         ret = device_probe(dev);
 373         if (ret)
 374                 return ret;
 375         *ctlrp = dev_get_priv(dev);
 376
 377         return 0;
 378 }
 379
 380 /* returns 0 if no match, 1 if match */
 381 int usb_match_device(const struct usb_device_descriptor *desc,
 382                      const struct usb_device_id *id)
 383 {
 384         if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
 385             id->idVendor != le16_to_cpu(desc->idVendor))
 386                 return 0;
 387
 388         if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
 389             id->idProduct != le16_to_cpu(desc->idProduct))
 390                 return 0;
 391
 392         /* No need to test id->bcdDevice_lo != 0, since 0 is never
 393            greater than any unsigned number. */
 394         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
 395             (id->bcdDevice_lo > le16_to_cpu(desc->bcdDevice)))
 396                 return 0;
 397
 398         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
 399             (id->bcdDevice_hi < le16_to_cpu(desc->bcdDevice)))
 400                 return 0;
 401
 402         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
 403             (id->bDeviceClass != desc->bDeviceClass))
 404                 return 0;
 405
 406         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
 407             (id->bDeviceSubClass != desc->bDeviceSubClass))
 408                 return 0;
 409
 410         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
 411             (id->bDeviceProtocol != desc->bDeviceProtocol))
 412                 return 0;
 413
 414         return 1;
 415 }
 416
 417 /* returns 0 if no match, 1 if match */
 418 int usb_match_one_id_intf(const struct usb_device_descriptor *desc,
 419                           const struct usb_interface_descriptor *int_desc,
 420                           const struct usb_device_id *id)
 421 {
 422         /* The interface class, subclass, protocol and number should never be
 423          * checked for a match if the device class is Vendor Specific,
 424          * unless the match record specifies the Vendor ID. */
 425         if (desc->bDeviceClass == USB_CLASS_VENDOR_SPEC &&
 426             !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
 427             (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
 428                                 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
 429                                 USB_DEVICE_ID_MATCH_INT_PROTOCOL |
 430                                 USB_DEVICE_ID_MATCH_INT_NUMBER)))
 431                 return 0;
 432
 433         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
 434             (id->bInterfaceClass != int_desc->bInterfaceClass))
 435                 return 0;
 436
 437         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
 438             (id->bInterfaceSubClass != int_desc->bInterfaceSubClass))
 439                 return 0;
 440
 441         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
 442             (id->bInterfaceProtocol != int_desc->bInterfaceProtocol))
 443                 return 0;
 444
 445         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) &&
 446             (id->bInterfaceNumber != int_desc->bInterfaceNumber))
 447                 return 0;
 448
 449         return 1;
 450 }
 451
 452 /* returns 0 if no match, 1 if match */
 453 int usb_match_one_id(struct usb_device_descriptor *desc,
 454                      struct usb_interface_descriptor *int_desc,
 455                      const struct usb_device_id *id)
 456 {
 457         if (!usb_match_device(desc, id))
 458                 return 0;
 459
 460         return usb_match_one_id_intf(desc, int_desc, id);
 461 }
 462
 463 /**
 464  * usb_find_and_bind_driver() - Find and bind the right USB driver
 465  *
 466  * This only looks at certain fields in the descriptor.
 467  */
 468 static int usb_find_and_bind_driver(struct udevice *parent,
 469                                     struct usb_device_descriptor *desc,
 470                                     struct usb_interface_descriptor *iface,
 471                                     int bus_seq, int devnum,
 472                                     struct udevice **devp)
 473 {
 474         struct usb_driver_entry *start, *entry;
 475         int n_ents;
 476         int ret;
 477         char name[30], *str;
 478
 479         *devp = NULL;
 480         debug("%s: Searching for driver\n", __func__);
 481         start = ll_entry_start(struct usb_driver_entry, usb_driver_entry);
 482         n_ents = ll_entry_count(struct usb_driver_entry, usb_driver_entry);
 483         for (entry = start; entry != start + n_ents; entry++) {
 484                 const struct usb_device_id *id;
 485                 struct udevice *dev;
 486                 const struct driver *drv;
 487                 struct usb_dev_platdata *plat;
 488
 489                 for (id = entry->match; id->match_flags; id++) {
 490                         if (!usb_match_one_id(desc, iface, id))
 491                                 continue;
 492
 493                         drv = entry->driver;
 494                         /*
 495                          * We could pass the descriptor to the driver as
 496                          * platdata (instead of NULL) and allow its bind()
 497                          * method to return -ENOENT if it doesn't support this
 498                          * device. That way we could continue the search to
 499                          * find another driver. For now this doesn't seem
 500                          * necesssary, so just bind the first match.
 501                          */
 502                         ret = device_bind(parent, drv, drv->name, NULL, -1,
 503                                           &dev);
 504                         if (ret)
 505                                 goto error;
 506                         debug("%s: Match found: %s\n", __func__, drv->name);
 507                         dev->driver_data = id->driver_info;
 508                         plat = dev_get_parent_platdata(dev);
 509                         plat->id = *id;
 510                         *devp = dev;
 511                         return 0;
 512                 }
 513         }
 514
 515         /* Bind a generic driver so that the device can be used */
 516         snprintf(name, sizeof(name), "generic_bus_%x_dev_%x", bus_seq, devnum);
 517         str = strdup(name);
 518         if (!str)
 519                 return -ENOMEM;
 520         ret = device_bind_driver(parent, "usb_dev_generic_drv", str, devp);
 521
 522 error:
 523         debug("%s: No match found: %d\n", __func__, ret);
 524         return ret;
 525 }
 526
 527 /**
 528  * usb_find_child() - Find an existing device which matches our needs
 529  *
 530  *
 531  */
 532 static int usb_find_child(struct udevice *parent,
 533                           struct usb_device_descriptor *desc,
 534                           struct usb_interface_descriptor *iface,
 535                           struct udevice **devp)
 536 {
 537         struct udevice *dev;
 538
 539         *devp = NULL;
 540         for (device_find_first_child(parent, &dev);
 541              dev;
 542              device_find_next_child(&dev)) {
 543                 struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
 544
 545                 /* If this device is already in use, skip it */
 546                 if (device_active(dev))
 547                         continue;
 548                 debug("   %s: name='%s', plat=%d, desc=%d\n", __func__,
 549                       dev->name, plat->id.bDeviceClass, desc->bDeviceClass);
 550                 if (usb_match_one_id(desc, iface, &plat->id)) {
 551                         *devp = dev;
 552                         return 0;
 553                 }
 554         }
 555
 556         return -ENOENT;
 557 }
 558
 559 int usb_scan_device(struct udevice *parent, int port,
 560                     enum usb_device_speed speed, struct udevice **devp)
 561 {
 562         struct udevice *dev;
 563         bool created = false;
 564         struct usb_dev_platdata *plat;
 565         struct usb_bus_priv *priv;
 566         struct usb_device *parent_udev;
 567         int ret;
 568         ALLOC_CACHE_ALIGN_BUFFER(struct usb_device, udev, 1);
 569         struct usb_interface_descriptor *iface = &udev->config.if_desc[0].desc;
 570
 571         *devp = NULL;
 572         memset(udev, '\0', sizeof(*udev));
 573         udev->controller_dev = usb_get_bus(parent);
 574         priv = dev_get_uclass_priv(udev->controller_dev);
 575
 576         /*
 577          * Somewhat nasty, this. We create a local device and use the normal
 578          * USB stack to read its descriptor. Then we know what type of device
 579          * to create for real.
 580          *
 581          * udev->dev is set to the parent, since we don't have a real device
 582          * yet. The USB stack should not access udev.dev anyway, except perhaps
 583          * to find the controller, and the controller will either be @parent,
 584          * or some parent of @parent.
 585          *
 586          * Another option might be to create the device as a generic USB
 587          * device, then morph it into the correct one when we know what it
 588          * should be. This means that a generic USB device would morph into
 589          * a network controller, or a USB flash stick, for example. However,
 590          * we don't support such morphing and it isn't clear that it would
 591          * be easy to do.
 592          *
 593          * Yet another option is to split out the USB stack parts of udev
 594          * into something like a 'struct urb' (as Linux does) which can exist
 595          * independently of any device. This feels cleaner, but calls for quite
 596          * a big change to the USB stack.
 597          *
 598          * For now, the approach is to set up an empty udev, read its
 599          * descriptor and assign it an address, then bind a real device and
 600          * stash the resulting information into the device's parent
 601          * platform data. Then when we probe it, usb_child_pre_probe() is called
 602          * and it will pull the information out of the stash.
 603          */
 604         udev->dev = parent;
 605         udev->speed = speed;
 606         udev->devnum = priv->next_addr + 1;
 607         udev->portnr = port;
 608         debug("Calling usb_setup_device(), portnr=%d\n", udev->portnr);
 609         parent_udev = device_get_uclass_id(parent) == UCLASS_USB_HUB ?
 610                 dev_get_parent_priv(parent) : NULL;
 611         ret = usb_setup_device(udev, priv->desc_before_addr, parent_udev);
 612         debug("read_descriptor for '%s': ret=%d\n", parent->name, ret);
 613         if (ret)
 614                 return ret;
 615         ret = usb_find_child(parent, &udev->descriptor, iface, &dev);
 616         debug("** usb_find_child returns %d\n", ret);
 617         if (ret) {
 618                 if (ret != -ENOENT)
 619                         return ret;
 620                 ret = usb_find_and_bind_driver(parent, &udev->descriptor, iface,
 621                                                udev->controller_dev->seq,
 622                                                udev->devnum, &dev);
 623                 if (ret)
 624                         return ret;
 625                 created = true;
 626         }
 627         plat = dev_get_parent_platdata(dev);
 628         debug("%s: Probing '%s', plat=%p\n", __func__, dev->name, plat);
 629         plat->devnum = udev->devnum;
 630         plat->udev = udev;
 631         priv->next_addr++;
 632         ret = device_probe(dev);
 633         if (ret) {
 634                 debug("%s: Device '%s' probe failed\n", __func__, dev->name);
 635                 priv->next_addr--;
 636                 if (created)
 637                         device_unbind(dev);
 638                 return ret;
 639         }
 640         *devp = dev;
 641
 642         return 0;
 643 }
 644
 645 /*
 646  * Detect if a USB device has been plugged or unplugged.
 647  */
 648 int usb_detect_change(void)
 649 {
 650         struct udevice *hub;
 651         struct uclass *uc;
 652         int change = 0;
 653         int ret;
 654
 655         ret = uclass_get(UCLASS_USB_HUB, &uc);
 656         if (ret)
 657                 return ret;
 658
 659         uclass_foreach_dev(hub, uc) {
 660                 struct usb_device *udev;
 661                 struct udevice *dev;
 662
 663                 if (!device_active(hub))
 664                         continue;
 665                 for (device_find_first_child(hub, &dev);
 666                      dev;
 667                      device_find_next_child(&dev)) {
 668                         struct usb_port_status status;
 669
 670                         if (!device_active(dev))
 671                                 continue;
 672
 673                         udev = dev_get_parent_priv(dev);
 674                         if (usb_get_port_status(udev, udev->portnr, &status)
 675                                         < 0)
 676                                 /* USB request failed */
 677                                 continue;
 678
 679                         if (le16_to_cpu(status.wPortChange) &
 680                             USB_PORT_STAT_C_CONNECTION)
 681                                 change++;
 682                 }
 683         }
 684
 685         return change;
 686 }
 687
 688 int usb_child_post_bind(struct udevice *dev)
 689 {
 690         struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
 691         const void *blob = gd->fdt_blob;
 692         int val;
 693
 694         if (dev->of_offset == -1)
 695                 return 0;
 696
 697         /* We only support matching a few things */
 698         val = fdtdec_get_int(blob, dev->of_offset, "usb,device-class", -1);
 699         if (val != -1) {
 700                 plat->id.match_flags |= USB_DEVICE_ID_MATCH_DEV_CLASS;
 701                 plat->id.bDeviceClass = val;
 702         }
 703         val = fdtdec_get_int(blob, dev->of_offset, "usb,interface-class", -1);
 704         if (val != -1) {
 705                 plat->id.match_flags |= USB_DEVICE_ID_MATCH_INT_CLASS;
 706                 plat->id.bInterfaceClass = val;
 707         }
 708
 709         return 0;
 710 }
 711
 712 struct udevice *usb_get_bus(struct udevice *dev)
 713 {
 714         struct udevice *bus;
 715
 716         for (bus = dev; bus && device_get_uclass_id(bus) != UCLASS_USB; )
 717                 bus = bus->parent;
 718         if (!bus) {
 719                 /* By design this cannot happen */
 720                 assert(bus);
 721                 debug("USB HUB '%s' does not have a controller\n", dev->name);
 722         }
 723
 724         return bus;
 725 }
 726
 727 int usb_child_pre_probe(struct udevice *dev)
 728 {
 729         struct usb_device *udev = dev_get_parent_priv(dev);
 730         struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
 731         int ret;
 732
 733         if (plat->udev) {
 734                 /*
 735                  * Copy over all the values set in the on stack struct
 736                  * usb_device in usb_scan_device() to our final struct
 737                  * usb_device for this dev.
 738                  */
 739                 *udev = *(plat->udev);
 740                 /* And clear plat->udev as it will not be valid for long */
 741                 plat->udev = NULL;
 742                 udev->dev = dev;
 743         } else {
 744                 /*
 745                  * This happens with devices which are explicitly bound
 746                  * instead of being discovered through usb_scan_device()
 747                  * such as sandbox emul devices.
 748                  */
 749                 udev->dev = dev;
 750                 udev->controller_dev = usb_get_bus(dev);
 751                 udev->devnum = plat->devnum;
 752
 753                 /*
 754                  * udev did not go through usb_scan_device(), so we need to
 755                  * select the config and read the config descriptors.
 756                  */
 757                 ret = usb_select_config(udev);
 758                 if (ret)
 759                         return ret;
 760         }
 761
 762         return 0;
 763 }
 764
 765 UCLASS_DRIVER(usb) = {
 766         .id             = UCLASS_USB,
 767         .name           = "usb",
 768         .flags          = DM_UC_FLAG_SEQ_ALIAS,
 769         .post_bind      = usb_post_bind,
 770         .priv_auto_alloc_size = sizeof(struct usb_uclass_priv),
 771         .per_child_auto_alloc_size = sizeof(struct usb_device),
 772         .per_device_auto_alloc_size = sizeof(struct usb_bus_priv),
 773         .child_post_bind = usb_child_post_bind,
 774         .child_pre_probe = usb_child_pre_probe,
 775         .per_child_platdata_auto_alloc_size = sizeof(struct usb_dev_platdata),
 776 };
 777
 778 UCLASS_DRIVER(usb_dev_generic) = {
 779         .id             = UCLASS_USB_DEV_GENERIC,
 780         .name           = "usb_dev_generic",
 781 };
 782
 783 U_BOOT_DRIVER(usb_dev_generic_drv) = {
 784         .id             = UCLASS_USB_DEV_GENERIC,
 785         .name           = "usb_dev_generic_drv",
 786 };