arm: socfpga: Enable all FPGA config support for Arria 10
[platform/kernel/u-boot.git] / 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 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 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 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 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 };