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, DM_REMOVE_NORMAL);
 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_setup_ehci_gadget(struct ehci_ctrl **ctlrp)
 352 {
 353         struct usb_platdata *plat;
 354         struct udevice *dev;
 355         int ret;
 356
 357         /* Find the old device and remove it */
 358         ret = uclass_find_device_by_seq(UCLASS_USB, 0, true, &dev);
 359         if (ret)
 360                 return ret;
 361         ret = device_remove(dev, DM_REMOVE_NORMAL);
 362         if (ret)
 363                 return ret;
 364
 365         plat = dev_get_platdata(dev);
 366         plat->init_type = USB_INIT_DEVICE;
 367         ret = device_probe(dev);
 368         if (ret)
 369                 return ret;
 370         *ctlrp = dev_get_priv(dev);
 371
 372         return 0;
 373 }
 374
 375 /* returns 0 if no match, 1 if match */
 376 static int usb_match_device(const struct usb_device_descriptor *desc,
 377                             const struct usb_device_id *id)
 378 {
 379         if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
 380             id->idVendor != le16_to_cpu(desc->idVendor))
 381                 return 0;
 382
 383         if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
 384             id->idProduct != le16_to_cpu(desc->idProduct))
 385                 return 0;
 386
 387         /* No need to test id->bcdDevice_lo != 0, since 0 is never
 388            greater than any unsigned number. */
 389         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
 390             (id->bcdDevice_lo > le16_to_cpu(desc->bcdDevice)))
 391                 return 0;
 392
 393         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
 394             (id->bcdDevice_hi < le16_to_cpu(desc->bcdDevice)))
 395                 return 0;
 396
 397         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
 398             (id->bDeviceClass != desc->bDeviceClass))
 399                 return 0;
 400
 401         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
 402             (id->bDeviceSubClass != desc->bDeviceSubClass))
 403                 return 0;
 404
 405         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
 406             (id->bDeviceProtocol != desc->bDeviceProtocol))
 407                 return 0;
 408
 409         return 1;
 410 }
 411
 412 /* returns 0 if no match, 1 if match */
 413 static int usb_match_one_id_intf(const struct usb_device_descriptor *desc,
 414                         const struct usb_interface_descriptor *int_desc,
 415                         const struct usb_device_id *id)
 416 {
 417         /* The interface class, subclass, protocol and number should never be
 418          * checked for a match if the device class is Vendor Specific,
 419          * unless the match record specifies the Vendor ID. */
 420         if (desc->bDeviceClass == USB_CLASS_VENDOR_SPEC &&
 421             !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
 422             (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
 423                                 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
 424                                 USB_DEVICE_ID_MATCH_INT_PROTOCOL |
 425                                 USB_DEVICE_ID_MATCH_INT_NUMBER)))
 426                 return 0;
 427
 428         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
 429             (id->bInterfaceClass != int_desc->bInterfaceClass))
 430                 return 0;
 431
 432         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
 433             (id->bInterfaceSubClass != int_desc->bInterfaceSubClass))
 434                 return 0;
 435
 436         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
 437             (id->bInterfaceProtocol != int_desc->bInterfaceProtocol))
 438                 return 0;
 439
 440         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) &&
 441             (id->bInterfaceNumber != int_desc->bInterfaceNumber))
 442                 return 0;
 443
 444         return 1;
 445 }
 446
 447 /* returns 0 if no match, 1 if match */
 448 static int usb_match_one_id(struct usb_device_descriptor *desc,
 449                             struct usb_interface_descriptor *int_desc,
 450                             const struct usb_device_id *id)
 451 {
 452         if (!usb_match_device(desc, id))
 453                 return 0;
 454
 455         return usb_match_one_id_intf(desc, int_desc, id);
 456 }
 457
 458 /**
 459  * usb_find_and_bind_driver() - Find and bind the right USB driver
 460  *
 461  * This only looks at certain fields in the descriptor.
 462  */
 463 static int usb_find_and_bind_driver(struct udevice *parent,
 464                                     struct usb_device_descriptor *desc,
 465                                     struct usb_interface_descriptor *iface,
 466                                     int bus_seq, int devnum,
 467                                     struct udevice **devp)
 468 {
 469         struct usb_driver_entry *start, *entry;
 470         int n_ents;
 471         int ret;
 472         char name[30], *str;
 473
 474         *devp = NULL;
 475         debug("%s: Searching for driver\n", __func__);
 476         start = ll_entry_start(struct usb_driver_entry, usb_driver_entry);
 477         n_ents = ll_entry_count(struct usb_driver_entry, usb_driver_entry);
 478         for (entry = start; entry != start + n_ents; entry++) {
 479                 const struct usb_device_id *id;
 480                 struct udevice *dev;
 481                 const struct driver *drv;
 482                 struct usb_dev_platdata *plat;
 483
 484                 for (id = entry->match; id->match_flags; id++) {
 485                         if (!usb_match_one_id(desc, iface, id))
 486                                 continue;
 487
 488                         drv = entry->driver;
 489                         /*
 490                          * We could pass the descriptor to the driver as
 491                          * platdata (instead of NULL) and allow its bind()
 492                          * method to return -ENOENT if it doesn't support this
 493                          * device. That way we could continue the search to
 494                          * find another driver. For now this doesn't seem
 495                          * necesssary, so just bind the first match.
 496                          */
 497                         ret = device_bind(parent, drv, drv->name, NULL, -1,
 498                                           &dev);
 499                         if (ret)
 500                                 goto error;
 501                         debug("%s: Match found: %s\n", __func__, drv->name);
 502                         dev->driver_data = id->driver_info;
 503                         plat = dev_get_parent_platdata(dev);
 504                         plat->id = *id;
 505                         *devp = dev;
 506                         return 0;
 507                 }
 508         }
 509
 510         /* Bind a generic driver so that the device can be used */
 511         snprintf(name, sizeof(name), "generic_bus_%x_dev_%x", bus_seq, devnum);
 512         str = strdup(name);
 513         if (!str)
 514                 return -ENOMEM;
 515         ret = device_bind_driver(parent, "usb_dev_generic_drv", str, devp);
 516
 517 error:
 518         debug("%s: No match found: %d\n", __func__, ret);
 519         return ret;
 520 }
 521
 522 /**
 523  * usb_find_child() - Find an existing device which matches our needs
 524  *
 525  *
 526  */
 527 static int usb_find_child(struct udevice *parent,
 528                           struct usb_device_descriptor *desc,
 529                           struct usb_interface_descriptor *iface,
 530                           struct udevice **devp)
 531 {
 532         struct udevice *dev;
 533
 534         *devp = NULL;
 535         for (device_find_first_child(parent, &dev);
 536              dev;
 537              device_find_next_child(&dev)) {
 538                 struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
 539
 540                 /* If this device is already in use, skip it */
 541                 if (device_active(dev))
 542                         continue;
 543                 debug("   %s: name='%s', plat=%d, desc=%d\n", __func__,
 544                       dev->name, plat->id.bDeviceClass, desc->bDeviceClass);
 545                 if (usb_match_one_id(desc, iface, &plat->id)) {
 546                         *devp = dev;
 547                         return 0;
 548                 }
 549         }
 550
 551         return -ENOENT;
 552 }
 553
 554 int usb_scan_device(struct udevice *parent, int port,
 555                     enum usb_device_speed speed, struct udevice **devp)
 556 {
 557         struct udevice *dev;
 558         bool created = false;
 559         struct usb_dev_platdata *plat;
 560         struct usb_bus_priv *priv;
 561         struct usb_device *parent_udev;
 562         int ret;
 563         ALLOC_CACHE_ALIGN_BUFFER(struct usb_device, udev, 1);
 564         struct usb_interface_descriptor *iface = &udev->config.if_desc[0].desc;
 565
 566         *devp = NULL;
 567         memset(udev, '\0', sizeof(*udev));
 568         udev->controller_dev = usb_get_bus(parent);
 569         priv = dev_get_uclass_priv(udev->controller_dev);
 570
 571         /*
 572          * Somewhat nasty, this. We create a local device and use the normal
 573          * USB stack to read its descriptor. Then we know what type of device
 574          * to create for real.
 575          *
 576          * udev->dev is set to the parent, since we don't have a real device
 577          * yet. The USB stack should not access udev.dev anyway, except perhaps
 578          * to find the controller, and the controller will either be @parent,
 579          * or some parent of @parent.
 580          *
 581          * Another option might be to create the device as a generic USB
 582          * device, then morph it into the correct one when we know what it
 583          * should be. This means that a generic USB device would morph into
 584          * a network controller, or a USB flash stick, for example. However,
 585          * we don't support such morphing and it isn't clear that it would
 586          * be easy to do.
 587          *
 588          * Yet another option is to split out the USB stack parts of udev
 589          * into something like a 'struct urb' (as Linux does) which can exist
 590          * independently of any device. This feels cleaner, but calls for quite
 591          * a big change to the USB stack.
 592          *
 593          * For now, the approach is to set up an empty udev, read its
 594          * descriptor and assign it an address, then bind a real device and
 595          * stash the resulting information into the device's parent
 596          * platform data. Then when we probe it, usb_child_pre_probe() is called
 597          * and it will pull the information out of the stash.
 598          */
 599         udev->dev = parent;
 600         udev->speed = speed;
 601         udev->devnum = priv->next_addr + 1;
 602         udev->portnr = port;
 603         debug("Calling usb_setup_device(), portnr=%d\n", udev->portnr);
 604         parent_udev = device_get_uclass_id(parent) == UCLASS_USB_HUB ?
 605                 dev_get_parent_priv(parent) : NULL;
 606         ret = usb_setup_device(udev, priv->desc_before_addr, parent_udev);
 607         debug("read_descriptor for '%s': ret=%d\n", parent->name, ret);
 608         if (ret)
 609                 return ret;
 610         ret = usb_find_child(parent, &udev->descriptor, iface, &dev);
 611         debug("** usb_find_child returns %d\n", ret);
 612         if (ret) {
 613                 if (ret != -ENOENT)
 614                         return ret;
 615                 ret = usb_find_and_bind_driver(parent, &udev->descriptor, iface,
 616                                                udev->controller_dev->seq,
 617                                                udev->devnum, &dev);
 618                 if (ret)
 619                         return ret;
 620                 created = true;
 621         }
 622         plat = dev_get_parent_platdata(dev);
 623         debug("%s: Probing '%s', plat=%p\n", __func__, dev->name, plat);
 624         plat->devnum = udev->devnum;
 625         plat->udev = udev;
 626         priv->next_addr++;
 627         ret = device_probe(dev);
 628         if (ret) {
 629                 debug("%s: Device '%s' probe failed\n", __func__, dev->name);
 630                 priv->next_addr--;
 631                 if (created)
 632                         device_unbind(dev);
 633                 return ret;
 634         }
 635         *devp = dev;
 636
 637         return 0;
 638 }
 639
 640 /*
 641  * Detect if a USB device has been plugged or unplugged.
 642  */
 643 int usb_detect_change(void)
 644 {
 645         struct udevice *hub;
 646         struct uclass *uc;
 647         int change = 0;
 648         int ret;
 649
 650         ret = uclass_get(UCLASS_USB_HUB, &uc);
 651         if (ret)
 652                 return ret;
 653
 654         uclass_foreach_dev(hub, uc) {
 655                 struct usb_device *udev;
 656                 struct udevice *dev;
 657
 658                 if (!device_active(hub))
 659                         continue;
 660                 for (device_find_first_child(hub, &dev);
 661                      dev;
 662                      device_find_next_child(&dev)) {
 663                         struct usb_port_status status;
 664
 665                         if (!device_active(dev))
 666                                 continue;
 667
 668                         udev = dev_get_parent_priv(dev);
 669                         if (usb_get_port_status(udev, udev->portnr, &status)
 670                                         < 0)
 671                                 /* USB request failed */
 672                                 continue;
 673
 674                         if (le16_to_cpu(status.wPortChange) &
 675                             USB_PORT_STAT_C_CONNECTION)
 676                                 change++;
 677                 }
 678         }
 679
 680         return change;
 681 }
 682
 683 static int usb_child_post_bind(struct udevice *dev)
 684 {
 685         struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
 686         int val;
 687
 688         if (!dev_of_valid(dev))
 689                 return 0;
 690
 691         /* We only support matching a few things */
 692         val = dev_read_u32_default(dev, "usb,device-class", -1);
 693         if (val != -1) {
 694                 plat->id.match_flags |= USB_DEVICE_ID_MATCH_DEV_CLASS;
 695                 plat->id.bDeviceClass = val;
 696         }
 697         val = dev_read_u32_default(dev, "usb,interface-class", -1);
 698         if (val != -1) {
 699                 plat->id.match_flags |= USB_DEVICE_ID_MATCH_INT_CLASS;
 700                 plat->id.bInterfaceClass = val;
 701         }
 702
 703         return 0;
 704 }
 705
 706 struct udevice *usb_get_bus(struct udevice *dev)
 707 {
 708         struct udevice *bus;
 709
 710         for (bus = dev; bus && device_get_uclass_id(bus) != UCLASS_USB; )
 711                 bus = bus->parent;
 712         if (!bus) {
 713                 /* By design this cannot happen */
 714                 assert(bus);
 715                 debug("USB HUB '%s' does not have a controller\n", dev->name);
 716         }
 717
 718         return bus;
 719 }
 720
 721 int usb_child_pre_probe(struct udevice *dev)
 722 {
 723         struct usb_device *udev = dev_get_parent_priv(dev);
 724         struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
 725         int ret;
 726
 727         if (plat->udev) {
 728                 /*
 729                  * Copy over all the values set in the on stack struct
 730                  * usb_device in usb_scan_device() to our final struct
 731                  * usb_device for this dev.
 732                  */
 733                 *udev = *(plat->udev);
 734                 /* And clear plat->udev as it will not be valid for long */
 735                 plat->udev = NULL;
 736                 udev->dev = dev;
 737         } else {
 738                 /*
 739                  * This happens with devices which are explicitly bound
 740                  * instead of being discovered through usb_scan_device()
 741                  * such as sandbox emul devices.
 742                  */
 743                 udev->dev = dev;
 744                 udev->controller_dev = usb_get_bus(dev);
 745                 udev->devnum = plat->devnum;
 746
 747                 /*
 748                  * udev did not go through usb_scan_device(), so we need to
 749                  * select the config and read the config descriptors.
 750                  */
 751                 ret = usb_select_config(udev);
 752                 if (ret)
 753                         return ret;
 754         }
 755
 756         return 0;
 757 }
 758
 759 UCLASS_DRIVER(usb) = {
 760         .id             = UCLASS_USB,
 761         .name           = "usb",
 762         .flags          = DM_UC_FLAG_SEQ_ALIAS,
 763         .post_bind      = dm_scan_fdt_dev,
 764         .priv_auto_alloc_size = sizeof(struct usb_uclass_priv),
 765         .per_child_auto_alloc_size = sizeof(struct usb_device),
 766         .per_device_auto_alloc_size = sizeof(struct usb_bus_priv),
 767         .child_post_bind = usb_child_post_bind,
 768         .child_pre_probe = usb_child_pre_probe,
 769         .per_child_platdata_auto_alloc_size = sizeof(struct usb_dev_platdata),
 770 };
 771
 772 UCLASS_DRIVER(usb_dev_generic) = {
 773         .id             = UCLASS_USB_DEV_GENERIC,
 774         .name           = "usb_dev_generic",
 775 };
 776
 777 U_BOOT_DRIVER(usb_dev_generic_drv) = {
 778         .id             = UCLASS_USB_DEV_GENERIC,
 779         .name           = "usb_dev_generic_drv",
 780 };