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[u-boot] / 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 int usb_init(void)
206 {
207         int controllers_initialized = 0;
208         struct usb_uclass_priv *uc_priv;
209         struct usb_bus_priv *priv;
210         struct udevice *bus;
211         struct uclass *uc;
212         int count = 0;
213         int ret;
214
215         asynch_allowed = 1;
216         usb_hub_reset();
217
218         ret = uclass_get(UCLASS_USB, &uc);
219         if (ret)
220                 return ret;
221
222         uc_priv = uc->priv;
223
224         uclass_foreach_dev(bus, uc) {
225                 /* init low_level USB */
226                 printf("USB%d:   ", count);
227                 count++;
228                 ret = device_probe(bus);
229                 if (ret == -ENODEV) {   /* No such device. */
230                         puts("Port not available.\n");
231                         controllers_initialized++;
232                         continue;
233                 }
234
235                 if (ret) {              /* Other error. */
236                         printf("probe failed, error %d\n", ret);
237                         continue;
238                 }
239                 controllers_initialized++;
240                 usb_started = true;
241         }
242
243         /*
244          * lowlevel init done, now scan the bus for devices i.e. search HUBs
245          * and configure them, first scan primary controllers.
246          */
247         uclass_foreach_dev(bus, uc) {
248                 if (!device_active(bus))
249                         continue;
250
251                 priv = dev_get_uclass_priv(bus);
252                 if (!priv->companion)
253                         usb_scan_bus(bus, true);
254         }
255
256         /*
257          * Now that the primary controllers have been scanned and have handed
258          * over any devices they do not understand to their companions, scan
259          * the companions if necessary.
260          */
261         if (uc_priv->companion_device_count) {
262                 uclass_foreach_dev(bus, uc) {
263                         if (!device_active(bus))
264                                 continue;
265
266                         priv = dev_get_uclass_priv(bus);
267                         if (priv->companion)
268                                 usb_scan_bus(bus, true);
269                 }
270         }
271
272         debug("scan end\n");
273         /* if we were not able to find at least one working bus, bail out */
274         if (!count)
275                 printf("No controllers found\n");
276         else if (controllers_initialized == 0)
277                 printf("USB error: all controllers failed lowlevel init\n");
278
279         return usb_started ? 0 : -1;
280 }
281
282 /*
283  * TODO(sjg@chromium.org): Remove this legacy function. At present it is needed
284  * to support boards which use driver model for USB but not Ethernet, and want
285  * to use USB Ethernet.
286  *
287  * The #if clause is here to ensure that remains the only case.
288  */
289 #if !defined(CONFIG_DM_ETH) && defined(CONFIG_USB_HOST_ETHER)
290 static struct usb_device *find_child_devnum(struct udevice *parent, int devnum)
291 {
292         struct usb_device *udev;
293         struct udevice *dev;
294
295         if (!device_active(parent))
296                 return NULL;
297         udev = dev_get_parent_priv(parent);
298         if (udev->devnum == devnum)
299                 return udev;
300
301         for (device_find_first_child(parent, &dev);
302              dev;
303              device_find_next_child(&dev)) {
304                 udev = find_child_devnum(dev, devnum);
305                 if (udev)
306                         return udev;
307         }
308
309         return NULL;
310 }
311
312 struct usb_device *usb_get_dev_index(struct udevice *bus, int index)
313 {
314         struct udevice *dev;
315         int devnum = index + 1; /* Addresses are allocated from 1 on USB */
316
317         device_find_first_child(bus, &dev);
318         if (!dev)
319                 return NULL;
320
321         return find_child_devnum(dev, devnum);
322 }
323 #endif
324
325 int usb_post_bind(struct udevice *dev)
326 {
327         /* Scan the bus for devices */
328         return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
329 }
330
331 int usb_setup_ehci_gadget(struct ehci_ctrl **ctlrp)
332 {
333         struct usb_platdata *plat;
334         struct udevice *dev;
335         int ret;
336
337         /* Find the old device and remove it */
338         ret = uclass_find_device_by_seq(UCLASS_USB, 0, true, &dev);
339         if (ret)
340                 return ret;
341         ret = device_remove(dev);
342         if (ret)
343                 return ret;
344
345         plat = dev_get_platdata(dev);
346         plat->init_type = USB_INIT_DEVICE;
347         ret = device_probe(dev);
348         if (ret)
349                 return ret;
350         *ctlrp = dev_get_priv(dev);
351
352         return 0;
353 }
354
355 /* returns 0 if no match, 1 if match */
356 int usb_match_device(const struct usb_device_descriptor *desc,
357                      const struct usb_device_id *id)
358 {
359         if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
360             id->idVendor != le16_to_cpu(desc->idVendor))
361                 return 0;
362
363         if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
364             id->idProduct != le16_to_cpu(desc->idProduct))
365                 return 0;
366
367         /* No need to test id->bcdDevice_lo != 0, since 0 is never
368            greater than any unsigned number. */
369         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
370             (id->bcdDevice_lo > le16_to_cpu(desc->bcdDevice)))
371                 return 0;
372
373         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
374             (id->bcdDevice_hi < le16_to_cpu(desc->bcdDevice)))
375                 return 0;
376
377         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
378             (id->bDeviceClass != desc->bDeviceClass))
379                 return 0;
380
381         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
382             (id->bDeviceSubClass != desc->bDeviceSubClass))
383                 return 0;
384
385         if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
386             (id->bDeviceProtocol != desc->bDeviceProtocol))
387                 return 0;
388
389         return 1;
390 }
391
392 /* returns 0 if no match, 1 if match */
393 int usb_match_one_id_intf(const struct usb_device_descriptor *desc,
394                           const struct usb_interface_descriptor *int_desc,
395                           const struct usb_device_id *id)
396 {
397         /* The interface class, subclass, protocol and number should never be
398          * checked for a match if the device class is Vendor Specific,
399          * unless the match record specifies the Vendor ID. */
400         if (desc->bDeviceClass == USB_CLASS_VENDOR_SPEC &&
401             !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
402             (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
403                                 USB_DEVICE_ID_MATCH_INT_SUBCLASS |
404                                 USB_DEVICE_ID_MATCH_INT_PROTOCOL |
405                                 USB_DEVICE_ID_MATCH_INT_NUMBER)))
406                 return 0;
407
408         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
409             (id->bInterfaceClass != int_desc->bInterfaceClass))
410                 return 0;
411
412         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
413             (id->bInterfaceSubClass != int_desc->bInterfaceSubClass))
414                 return 0;
415
416         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
417             (id->bInterfaceProtocol != int_desc->bInterfaceProtocol))
418                 return 0;
419
420         if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) &&
421             (id->bInterfaceNumber != int_desc->bInterfaceNumber))
422                 return 0;
423
424         return 1;
425 }
426
427 /* returns 0 if no match, 1 if match */
428 int usb_match_one_id(struct usb_device_descriptor *desc,
429                      struct usb_interface_descriptor *int_desc,
430                      const struct usb_device_id *id)
431 {
432         if (!usb_match_device(desc, id))
433                 return 0;
434
435         return usb_match_one_id_intf(desc, int_desc, id);
436 }
437
438 /**
439  * usb_find_and_bind_driver() - Find and bind the right USB driver
440  *
441  * This only looks at certain fields in the descriptor.
442  */
443 static int usb_find_and_bind_driver(struct udevice *parent,
444                                     struct usb_device_descriptor *desc,
445                                     struct usb_interface_descriptor *iface,
446                                     int bus_seq, int devnum,
447                                     struct udevice **devp)
448 {
449         struct usb_driver_entry *start, *entry;
450         int n_ents;
451         int ret;
452         char name[30], *str;
453
454         *devp = NULL;
455         debug("%s: Searching for driver\n", __func__);
456         start = ll_entry_start(struct usb_driver_entry, usb_driver_entry);
457         n_ents = ll_entry_count(struct usb_driver_entry, usb_driver_entry);
458         for (entry = start; entry != start + n_ents; entry++) {
459                 const struct usb_device_id *id;
460                 struct udevice *dev;
461                 const struct driver *drv;
462                 struct usb_dev_platdata *plat;
463
464                 for (id = entry->match; id->match_flags; id++) {
465                         if (!usb_match_one_id(desc, iface, id))
466                                 continue;
467
468                         drv = entry->driver;
469                         /*
470                          * We could pass the descriptor to the driver as
471                          * platdata (instead of NULL) and allow its bind()
472                          * method to return -ENOENT if it doesn't support this
473                          * device. That way we could continue the search to
474                          * find another driver. For now this doesn't seem
475                          * necesssary, so just bind the first match.
476                          */
477                         ret = device_bind(parent, drv, drv->name, NULL, -1,
478                                           &dev);
479                         if (ret)
480                                 goto error;
481                         debug("%s: Match found: %s\n", __func__, drv->name);
482                         dev->driver_data = id->driver_info;
483                         plat = dev_get_parent_platdata(dev);
484                         plat->id = *id;
485                         *devp = dev;
486                         return 0;
487                 }
488         }
489
490         /* Bind a generic driver so that the device can be used */
491         snprintf(name, sizeof(name), "generic_bus_%x_dev_%x", bus_seq, devnum);
492         str = strdup(name);
493         if (!str)
494                 return -ENOMEM;
495         ret = device_bind_driver(parent, "usb_dev_generic_drv", str, devp);
496
497 error:
498         debug("%s: No match found: %d\n", __func__, ret);
499         return ret;
500 }
501
502 /**
503  * usb_find_child() - Find an existing device which matches our needs
504  *
505  *
506  */
507 static int usb_find_child(struct udevice *parent,
508                           struct usb_device_descriptor *desc,
509                           struct usb_interface_descriptor *iface,
510                           struct udevice **devp)
511 {
512         struct udevice *dev;
513
514         *devp = NULL;
515         for (device_find_first_child(parent, &dev);
516              dev;
517              device_find_next_child(&dev)) {
518                 struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
519
520                 /* If this device is already in use, skip it */
521                 if (device_active(dev))
522                         continue;
523                 debug("   %s: name='%s', plat=%d, desc=%d\n", __func__,
524                       dev->name, plat->id.bDeviceClass, desc->bDeviceClass);
525                 if (usb_match_one_id(desc, iface, &plat->id)) {
526                         *devp = dev;
527                         return 0;
528                 }
529         }
530
531         return -ENOENT;
532 }
533
534 int usb_scan_device(struct udevice *parent, int port,
535                     enum usb_device_speed speed, struct udevice **devp)
536 {
537         struct udevice *dev;
538         bool created = false;
539         struct usb_dev_platdata *plat;
540         struct usb_bus_priv *priv;
541         struct usb_device *parent_udev;
542         int ret;
543         ALLOC_CACHE_ALIGN_BUFFER(struct usb_device, udev, 1);
544         struct usb_interface_descriptor *iface = &udev->config.if_desc[0].desc;
545
546         *devp = NULL;
547         memset(udev, '\0', sizeof(*udev));
548         udev->controller_dev = usb_get_bus(parent);
549         priv = dev_get_uclass_priv(udev->controller_dev);
550
551         /*
552          * Somewhat nasty, this. We create a local device and use the normal
553          * USB stack to read its descriptor. Then we know what type of device
554          * to create for real.
555          *
556          * udev->dev is set to the parent, since we don't have a real device
557          * yet. The USB stack should not access udev.dev anyway, except perhaps
558          * to find the controller, and the controller will either be @parent,
559          * or some parent of @parent.
560          *
561          * Another option might be to create the device as a generic USB
562          * device, then morph it into the correct one when we know what it
563          * should be. This means that a generic USB device would morph into
564          * a network controller, or a USB flash stick, for example. However,
565          * we don't support such morphing and it isn't clear that it would
566          * be easy to do.
567          *
568          * Yet another option is to split out the USB stack parts of udev
569          * into something like a 'struct urb' (as Linux does) which can exist
570          * independently of any device. This feels cleaner, but calls for quite
571          * a big change to the USB stack.
572          *
573          * For now, the approach is to set up an empty udev, read its
574          * descriptor and assign it an address, then bind a real device and
575          * stash the resulting information into the device's parent
576          * platform data. Then when we probe it, usb_child_pre_probe() is called
577          * and it will pull the information out of the stash.
578          */
579         udev->dev = parent;
580         udev->speed = speed;
581         udev->devnum = priv->next_addr + 1;
582         udev->portnr = port;
583         debug("Calling usb_setup_device(), portnr=%d\n", udev->portnr);
584         parent_udev = device_get_uclass_id(parent) == UCLASS_USB_HUB ?
585                 dev_get_parent_priv(parent) : NULL;
586         ret = usb_setup_device(udev, priv->desc_before_addr, parent_udev);
587         debug("read_descriptor for '%s': ret=%d\n", parent->name, ret);
588         if (ret)
589                 return ret;
590         ret = usb_find_child(parent, &udev->descriptor, iface, &dev);
591         debug("** usb_find_child returns %d\n", ret);
592         if (ret) {
593                 if (ret != -ENOENT)
594                         return ret;
595                 ret = usb_find_and_bind_driver(parent, &udev->descriptor, iface,
596                                                udev->controller_dev->seq,
597                                                udev->devnum, &dev);
598                 if (ret)
599                         return ret;
600                 created = true;
601         }
602         plat = dev_get_parent_platdata(dev);
603         debug("%s: Probing '%s', plat=%p\n", __func__, dev->name, plat);
604         plat->devnum = udev->devnum;
605         plat->udev = udev;
606         priv->next_addr++;
607         ret = device_probe(dev);
608         if (ret) {
609                 debug("%s: Device '%s' probe failed\n", __func__, dev->name);
610                 priv->next_addr--;
611                 if (created)
612                         device_unbind(dev);
613                 return ret;
614         }
615         *devp = dev;
616
617         return 0;
618 }
619
620 /*
621  * Detect if a USB device has been plugged or unplugged.
622  */
623 int usb_detect_change(void)
624 {
625         struct udevice *hub;
626         struct uclass *uc;
627         int change = 0;
628         int ret;
629
630         ret = uclass_get(UCLASS_USB_HUB, &uc);
631         if (ret)
632                 return ret;
633
634         uclass_foreach_dev(hub, uc) {
635                 struct usb_device *udev;
636                 struct udevice *dev;
637
638                 if (!device_active(hub))
639                         continue;
640                 for (device_find_first_child(hub, &dev);
641                      dev;
642                      device_find_next_child(&dev)) {
643                         struct usb_port_status status;
644
645                         if (!device_active(dev))
646                                 continue;
647
648                         udev = dev_get_parent_priv(dev);
649                         if (usb_get_port_status(udev, udev->portnr, &status)
650                                         < 0)
651                                 /* USB request failed */
652                                 continue;
653
654                         if (le16_to_cpu(status.wPortChange) &
655                             USB_PORT_STAT_C_CONNECTION)
656                                 change++;
657                 }
658         }
659
660         return change;
661 }
662
663 int usb_child_post_bind(struct udevice *dev)
664 {
665         struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
666         const void *blob = gd->fdt_blob;
667         int val;
668
669         if (dev->of_offset == -1)
670                 return 0;
671
672         /* We only support matching a few things */
673         val = fdtdec_get_int(blob, dev->of_offset, "usb,device-class", -1);
674         if (val != -1) {
675                 plat->id.match_flags |= USB_DEVICE_ID_MATCH_DEV_CLASS;
676                 plat->id.bDeviceClass = val;
677         }
678         val = fdtdec_get_int(blob, dev->of_offset, "usb,interface-class", -1);
679         if (val != -1) {
680                 plat->id.match_flags |= USB_DEVICE_ID_MATCH_INT_CLASS;
681                 plat->id.bInterfaceClass = val;
682         }
683
684         return 0;
685 }
686
687 struct udevice *usb_get_bus(struct udevice *dev)
688 {
689         struct udevice *bus;
690
691         for (bus = dev; bus && device_get_uclass_id(bus) != UCLASS_USB; )
692                 bus = bus->parent;
693         if (!bus) {
694                 /* By design this cannot happen */
695                 assert(bus);
696                 debug("USB HUB '%s' does not have a controller\n", dev->name);
697         }
698
699         return bus;
700 }
701
702 int usb_child_pre_probe(struct udevice *dev)
703 {
704         struct usb_device *udev = dev_get_parent_priv(dev);
705         struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
706         int ret;
707
708         if (plat->udev) {
709                 /*
710                  * Copy over all the values set in the on stack struct
711                  * usb_device in usb_scan_device() to our final struct
712                  * usb_device for this dev.
713                  */
714                 *udev = *(plat->udev);
715                 /* And clear plat->udev as it will not be valid for long */
716                 plat->udev = NULL;
717                 udev->dev = dev;
718         } else {
719                 /*
720                  * This happens with devices which are explicitly bound
721                  * instead of being discovered through usb_scan_device()
722                  * such as sandbox emul devices.
723                  */
724                 udev->dev = dev;
725                 udev->controller_dev = usb_get_bus(dev);
726                 udev->devnum = plat->devnum;
727
728                 /*
729                  * udev did not go through usb_scan_device(), so we need to
730                  * select the config and read the config descriptors.
731                  */
732                 ret = usb_select_config(udev);
733                 if (ret)
734                         return ret;
735         }
736
737         return 0;
738 }
739
740 UCLASS_DRIVER(usb) = {
741         .id             = UCLASS_USB,
742         .name           = "usb",
743         .flags          = DM_UC_FLAG_SEQ_ALIAS,
744         .post_bind      = usb_post_bind,
745         .priv_auto_alloc_size = sizeof(struct usb_uclass_priv),
746         .per_child_auto_alloc_size = sizeof(struct usb_device),
747         .per_device_auto_alloc_size = sizeof(struct usb_bus_priv),
748         .child_post_bind = usb_child_post_bind,
749         .child_pre_probe = usb_child_pre_probe,
750         .per_child_platdata_auto_alloc_size = sizeof(struct usb_dev_platdata),
751 };
752
753 UCLASS_DRIVER(usb_dev_generic) = {
754         .id             = UCLASS_USB_DEV_GENERIC,
755         .name           = "usb_dev_generic",
756 };
757
758 U_BOOT_DRIVER(usb_dev_generic_drv) = {
759         .id             = UCLASS_USB_DEV_GENERIC,
760         .name           = "usb_dev_generic_drv",
761 };