xref: /rk3399_rockchip-uboot/drivers/usb/host/usb-uclass.c (revision 4f46a20e4b713fa26f95da83998732492d13c711)
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_update_hub_device(struct usb_device *udev)
143 {
144 	struct udevice *bus = udev->controller_dev;
145 	struct dm_usb_ops *ops = usb_get_ops(bus);
146 
147 	if (!ops->update_hub_device)
148 		return -ENOSYS;
149 
150 	return ops->update_hub_device(bus, udev);
151 }
152 
153 int usb_get_max_xfer_size(struct usb_device *udev, size_t *size)
154 {
155 	struct udevice *bus = udev->controller_dev;
156 	struct dm_usb_ops *ops = usb_get_ops(bus);
157 
158 	if (!ops->get_max_xfer_size)
159 		return -ENOSYS;
160 
161 	return ops->get_max_xfer_size(bus, size);
162 }
163 
164 int usb_stop(void)
165 {
166 	struct udevice *bus;
167 	struct udevice *rh;
168 	struct uclass *uc;
169 	struct usb_uclass_priv *uc_priv;
170 	int err = 0, ret;
171 
172 	/* De-activate any devices that have been activated */
173 	ret = uclass_get(UCLASS_USB, &uc);
174 	if (ret)
175 		return ret;
176 
177 	uc_priv = uc->priv;
178 
179 	uclass_foreach_dev(bus, uc) {
180 		ret = device_remove(bus, DM_REMOVE_NORMAL);
181 		if (ret && !err)
182 			err = ret;
183 
184 		/* Locate root hub device */
185 		device_find_first_child(bus, &rh);
186 		if (rh) {
187 			/*
188 			 * All USB devices are children of root hub.
189 			 * Unbinding root hub will unbind all of its children.
190 			 */
191 			ret = device_unbind(rh);
192 			if (ret && !err)
193 				err = ret;
194 		}
195 	}
196 #ifdef CONFIG_BLK
197 	ret = blk_unbind_all(IF_TYPE_USB);
198 	if (ret && !err)
199 		err = ret;
200 #endif
201 #ifdef CONFIG_SANDBOX
202 	struct udevice *dev;
203 
204 	/* Reset all enulation devices */
205 	ret = uclass_get(UCLASS_USB_EMUL, &uc);
206 	if (ret)
207 		return ret;
208 
209 	uclass_foreach_dev(dev, uc)
210 		usb_emul_reset(dev);
211 #endif
212 #ifdef CONFIG_USB_STORAGE
213 	usb_stor_reset();
214 #endif
215 	uc_priv->companion_device_count = 0;
216 	usb_started = 0;
217 
218 	return err;
219 }
220 
221 static void usb_scan_bus(struct udevice *bus, bool recurse)
222 {
223 	struct usb_bus_priv *priv;
224 	struct udevice *dev;
225 	int ret;
226 
227 	priv = dev_get_uclass_priv(bus);
228 
229 	assert(recurse);	/* TODO: Support non-recusive */
230 
231 	printf("scanning bus %d for devices... ", bus->seq);
232 	debug("\n");
233 	ret = usb_scan_device(bus, 0, USB_SPEED_FULL, &dev);
234 	if (ret)
235 		printf("failed, error %d\n", ret);
236 	else if (priv->next_addr == 0)
237 		printf("No USB Device found\n");
238 	else
239 		printf("%d USB Device(s) found\n", priv->next_addr);
240 }
241 
242 static void remove_inactive_children(struct uclass *uc, struct udevice *bus)
243 {
244 	uclass_foreach_dev(bus, uc) {
245 		struct udevice *dev, *next;
246 
247 		if (!device_active(bus))
248 			continue;
249 		device_foreach_child_safe(dev, next, bus) {
250 			if (!device_active(dev))
251 				device_unbind(dev);
252 		}
253 	}
254 }
255 
256 int usb_init(void)
257 {
258 	int controllers_initialized = 0;
259 	struct usb_uclass_priv *uc_priv;
260 	struct usb_bus_priv *priv;
261 	struct udevice *bus;
262 	struct uclass *uc;
263 	int count = 0;
264 	int ret;
265 
266 	asynch_allowed = 1;
267 
268 	ret = uclass_get(UCLASS_USB, &uc);
269 	if (ret)
270 		return ret;
271 
272 	uc_priv = uc->priv;
273 
274 	uclass_foreach_dev(bus, uc) {
275 		/* init low_level USB */
276 		printf("USB%d:   ", count);
277 		count++;
278 
279 #ifdef CONFIG_SANDBOX
280 		/*
281 		 * For Sandbox, we need scan the device tree each time when we
282 		 * start the USB stack, in order to re-create the emulated USB
283 		 * devices and bind drivers for them before we actually do the
284 		 * driver probe.
285 		 */
286 		ret = dm_scan_fdt_dev(bus);
287 		if (ret) {
288 			printf("Sandbox USB device scan failed (%d)\n", ret);
289 			continue;
290 		}
291 #endif
292 
293 		ret = device_probe(bus);
294 		if (ret == -ENODEV) {	/* No such device. */
295 			puts("Port not available.\n");
296 			controllers_initialized++;
297 			continue;
298 		}
299 
300 		if (ret) {		/* Other error. */
301 			printf("probe failed, error %d\n", ret);
302 			continue;
303 		}
304 		controllers_initialized++;
305 		usb_started = true;
306 	}
307 
308 	/*
309 	 * lowlevel init done, now scan the bus for devices i.e. search HUBs
310 	 * and configure them, first scan primary controllers.
311 	 */
312 	uclass_foreach_dev(bus, uc) {
313 		if (!device_active(bus))
314 			continue;
315 
316 		priv = dev_get_uclass_priv(bus);
317 		if (!priv->companion)
318 			usb_scan_bus(bus, true);
319 	}
320 
321 	/*
322 	 * Now that the primary controllers have been scanned and have handed
323 	 * over any devices they do not understand to their companions, scan
324 	 * the companions if necessary.
325 	 */
326 	if (uc_priv->companion_device_count) {
327 		uclass_foreach_dev(bus, uc) {
328 			if (!device_active(bus))
329 				continue;
330 
331 			priv = dev_get_uclass_priv(bus);
332 			if (priv->companion)
333 				usb_scan_bus(bus, true);
334 		}
335 	}
336 
337 	debug("scan end\n");
338 
339 	/* Remove any devices that were not found on this scan */
340 	remove_inactive_children(uc, bus);
341 
342 	ret = uclass_get(UCLASS_USB_HUB, &uc);
343 	if (ret)
344 		return ret;
345 	remove_inactive_children(uc, bus);
346 
347 	/* if we were not able to find at least one working bus, bail out */
348 	if (!count)
349 		printf("No controllers found\n");
350 	else if (controllers_initialized == 0)
351 		printf("USB error: all controllers failed lowlevel init\n");
352 
353 	return usb_started ? 0 : -1;
354 }
355 
356 /*
357  * TODO(sjg@chromium.org): Remove this legacy function. At present it is needed
358  * to support boards which use driver model for USB but not Ethernet, and want
359  * to use USB Ethernet.
360  *
361  * The #if clause is here to ensure that remains the only case.
362  */
363 #if !defined(CONFIG_DM_ETH) && defined(CONFIG_USB_HOST_ETHER)
364 static struct usb_device *find_child_devnum(struct udevice *parent, int devnum)
365 {
366 	struct usb_device *udev;
367 	struct udevice *dev;
368 
369 	if (!device_active(parent))
370 		return NULL;
371 	udev = dev_get_parent_priv(parent);
372 	if (udev->devnum == devnum)
373 		return udev;
374 
375 	for (device_find_first_child(parent, &dev);
376 	     dev;
377 	     device_find_next_child(&dev)) {
378 		udev = find_child_devnum(dev, devnum);
379 		if (udev)
380 			return udev;
381 	}
382 
383 	return NULL;
384 }
385 
386 struct usb_device *usb_get_dev_index(struct udevice *bus, int index)
387 {
388 	struct udevice *dev;
389 	int devnum = index + 1; /* Addresses are allocated from 1 on USB */
390 
391 	device_find_first_child(bus, &dev);
392 	if (!dev)
393 		return NULL;
394 
395 	return find_child_devnum(dev, devnum);
396 }
397 #endif
398 
399 int usb_setup_ehci_gadget(struct ehci_ctrl **ctlrp)
400 {
401 	struct usb_platdata *plat;
402 	struct udevice *dev;
403 	int ret;
404 
405 	/* Find the old device and remove it */
406 	ret = uclass_find_device_by_seq(UCLASS_USB, 0, true, &dev);
407 	if (ret)
408 		return ret;
409 	ret = device_remove(dev, DM_REMOVE_NORMAL);
410 	if (ret)
411 		return ret;
412 
413 	plat = dev_get_platdata(dev);
414 	plat->init_type = USB_INIT_DEVICE;
415 	ret = device_probe(dev);
416 	if (ret)
417 		return ret;
418 	*ctlrp = dev_get_priv(dev);
419 
420 	return 0;
421 }
422 
423 /* returns 0 if no match, 1 if match */
424 static int usb_match_device(const struct usb_device_descriptor *desc,
425 			    const struct usb_device_id *id)
426 {
427 	if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
428 	    id->idVendor != le16_to_cpu(desc->idVendor))
429 		return 0;
430 
431 	if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
432 	    id->idProduct != le16_to_cpu(desc->idProduct))
433 		return 0;
434 
435 	/* No need to test id->bcdDevice_lo != 0, since 0 is never
436 	   greater than any unsigned number. */
437 	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
438 	    (id->bcdDevice_lo > le16_to_cpu(desc->bcdDevice)))
439 		return 0;
440 
441 	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
442 	    (id->bcdDevice_hi < le16_to_cpu(desc->bcdDevice)))
443 		return 0;
444 
445 	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
446 	    (id->bDeviceClass != desc->bDeviceClass))
447 		return 0;
448 
449 	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
450 	    (id->bDeviceSubClass != desc->bDeviceSubClass))
451 		return 0;
452 
453 	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
454 	    (id->bDeviceProtocol != desc->bDeviceProtocol))
455 		return 0;
456 
457 	return 1;
458 }
459 
460 /* returns 0 if no match, 1 if match */
461 static int usb_match_one_id_intf(const struct usb_device_descriptor *desc,
462 			const struct usb_interface_descriptor *int_desc,
463 			const struct usb_device_id *id)
464 {
465 	/* The interface class, subclass, protocol and number should never be
466 	 * checked for a match if the device class is Vendor Specific,
467 	 * unless the match record specifies the Vendor ID. */
468 	if (desc->bDeviceClass == USB_CLASS_VENDOR_SPEC &&
469 	    !(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
470 	    (id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
471 				USB_DEVICE_ID_MATCH_INT_SUBCLASS |
472 				USB_DEVICE_ID_MATCH_INT_PROTOCOL |
473 				USB_DEVICE_ID_MATCH_INT_NUMBER)))
474 		return 0;
475 
476 	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
477 	    (id->bInterfaceClass != int_desc->bInterfaceClass))
478 		return 0;
479 
480 	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
481 	    (id->bInterfaceSubClass != int_desc->bInterfaceSubClass))
482 		return 0;
483 
484 	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
485 	    (id->bInterfaceProtocol != int_desc->bInterfaceProtocol))
486 		return 0;
487 
488 	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) &&
489 	    (id->bInterfaceNumber != int_desc->bInterfaceNumber))
490 		return 0;
491 
492 	return 1;
493 }
494 
495 /* returns 0 if no match, 1 if match */
496 static int usb_match_one_id(struct usb_device_descriptor *desc,
497 			    struct usb_interface_descriptor *int_desc,
498 			    const struct usb_device_id *id)
499 {
500 	if (!usb_match_device(desc, id))
501 		return 0;
502 
503 	return usb_match_one_id_intf(desc, int_desc, id);
504 }
505 
506 /**
507  * usb_find_and_bind_driver() - Find and bind the right USB driver
508  *
509  * This only looks at certain fields in the descriptor.
510  */
511 static int usb_find_and_bind_driver(struct udevice *parent,
512 				    struct usb_device_descriptor *desc,
513 				    struct usb_interface_descriptor *iface,
514 				    int bus_seq, int devnum,
515 				    struct udevice **devp)
516 {
517 	struct usb_driver_entry *start, *entry;
518 	int n_ents;
519 	int ret;
520 	char name[30], *str;
521 
522 	*devp = NULL;
523 	debug("%s: Searching for driver\n", __func__);
524 	start = ll_entry_start(struct usb_driver_entry, usb_driver_entry);
525 	n_ents = ll_entry_count(struct usb_driver_entry, usb_driver_entry);
526 	for (entry = start; entry != start + n_ents; entry++) {
527 		const struct usb_device_id *id;
528 		struct udevice *dev;
529 		const struct driver *drv;
530 		struct usb_dev_platdata *plat;
531 
532 		for (id = entry->match; id->match_flags; id++) {
533 			if (!usb_match_one_id(desc, iface, id))
534 				continue;
535 
536 			drv = entry->driver;
537 			/*
538 			 * We could pass the descriptor to the driver as
539 			 * platdata (instead of NULL) and allow its bind()
540 			 * method to return -ENOENT if it doesn't support this
541 			 * device. That way we could continue the search to
542 			 * find another driver. For now this doesn't seem
543 			 * necesssary, so just bind the first match.
544 			 */
545 			ret = device_bind(parent, drv, drv->name, NULL, -1,
546 					  &dev);
547 			if (ret)
548 				goto error;
549 			debug("%s: Match found: %s\n", __func__, drv->name);
550 			dev->driver_data = id->driver_info;
551 			plat = dev_get_parent_platdata(dev);
552 			plat->id = *id;
553 			*devp = dev;
554 			return 0;
555 		}
556 	}
557 
558 	/* Bind a generic driver so that the device can be used */
559 	snprintf(name, sizeof(name), "generic_bus_%x_dev_%x", bus_seq, devnum);
560 	str = strdup(name);
561 	if (!str)
562 		return -ENOMEM;
563 	ret = device_bind_driver(parent, "usb_dev_generic_drv", str, devp);
564 
565 error:
566 	debug("%s: No match found: %d\n", __func__, ret);
567 	return ret;
568 }
569 
570 /**
571  * usb_find_child() - Find an existing device which matches our needs
572  *
573  *
574  */
575 static int usb_find_child(struct udevice *parent,
576 			  struct usb_device_descriptor *desc,
577 			  struct usb_interface_descriptor *iface,
578 			  struct udevice **devp)
579 {
580 	struct udevice *dev;
581 
582 	*devp = NULL;
583 	for (device_find_first_child(parent, &dev);
584 	     dev;
585 	     device_find_next_child(&dev)) {
586 		struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
587 
588 		/* If this device is already in use, skip it */
589 		if (device_active(dev))
590 			continue;
591 		debug("   %s: name='%s', plat=%d, desc=%d\n", __func__,
592 		      dev->name, plat->id.bDeviceClass, desc->bDeviceClass);
593 		if (usb_match_one_id(desc, iface, &plat->id)) {
594 			*devp = dev;
595 			return 0;
596 		}
597 	}
598 
599 	return -ENOENT;
600 }
601 
602 int usb_scan_device(struct udevice *parent, int port,
603 		    enum usb_device_speed speed, struct udevice **devp)
604 {
605 	struct udevice *dev;
606 	bool created = false;
607 	struct usb_dev_platdata *plat;
608 	struct usb_bus_priv *priv;
609 	struct usb_device *parent_udev;
610 	int ret;
611 	ALLOC_CACHE_ALIGN_BUFFER(struct usb_device, udev, 1);
612 	struct usb_interface_descriptor *iface = &udev->config.if_desc[0].desc;
613 
614 	*devp = NULL;
615 	memset(udev, '\0', sizeof(*udev));
616 	udev->controller_dev = usb_get_bus(parent);
617 	priv = dev_get_uclass_priv(udev->controller_dev);
618 
619 	/*
620 	 * Somewhat nasty, this. We create a local device and use the normal
621 	 * USB stack to read its descriptor. Then we know what type of device
622 	 * to create for real.
623 	 *
624 	 * udev->dev is set to the parent, since we don't have a real device
625 	 * yet. The USB stack should not access udev.dev anyway, except perhaps
626 	 * to find the controller, and the controller will either be @parent,
627 	 * or some parent of @parent.
628 	 *
629 	 * Another option might be to create the device as a generic USB
630 	 * device, then morph it into the correct one when we know what it
631 	 * should be. This means that a generic USB device would morph into
632 	 * a network controller, or a USB flash stick, for example. However,
633 	 * we don't support such morphing and it isn't clear that it would
634 	 * be easy to do.
635 	 *
636 	 * Yet another option is to split out the USB stack parts of udev
637 	 * into something like a 'struct urb' (as Linux does) which can exist
638 	 * independently of any device. This feels cleaner, but calls for quite
639 	 * a big change to the USB stack.
640 	 *
641 	 * For now, the approach is to set up an empty udev, read its
642 	 * descriptor and assign it an address, then bind a real device and
643 	 * stash the resulting information into the device's parent
644 	 * platform data. Then when we probe it, usb_child_pre_probe() is called
645 	 * and it will pull the information out of the stash.
646 	 */
647 	udev->dev = parent;
648 	udev->speed = speed;
649 	udev->devnum = priv->next_addr + 1;
650 	udev->portnr = port;
651 	debug("Calling usb_setup_device(), portnr=%d\n", udev->portnr);
652 	parent_udev = device_get_uclass_id(parent) == UCLASS_USB_HUB ?
653 		dev_get_parent_priv(parent) : NULL;
654 	ret = usb_setup_device(udev, priv->desc_before_addr, parent_udev);
655 	debug("read_descriptor for '%s': ret=%d\n", parent->name, ret);
656 	if (ret)
657 		return ret;
658 	ret = usb_find_child(parent, &udev->descriptor, iface, &dev);
659 	debug("** usb_find_child returns %d\n", ret);
660 	if (ret) {
661 		if (ret != -ENOENT)
662 			return ret;
663 		ret = usb_find_and_bind_driver(parent, &udev->descriptor, iface,
664 					       udev->controller_dev->seq,
665 					       udev->devnum, &dev);
666 		if (ret)
667 			return ret;
668 		created = true;
669 	}
670 	plat = dev_get_parent_platdata(dev);
671 	debug("%s: Probing '%s', plat=%p\n", __func__, dev->name, plat);
672 	plat->devnum = udev->devnum;
673 	plat->udev = udev;
674 	priv->next_addr++;
675 	ret = device_probe(dev);
676 	if (ret) {
677 		debug("%s: Device '%s' probe failed\n", __func__, dev->name);
678 		priv->next_addr--;
679 		if (created)
680 			device_unbind(dev);
681 		return ret;
682 	}
683 	*devp = dev;
684 
685 	return 0;
686 }
687 
688 /*
689  * Detect if a USB device has been plugged or unplugged.
690  */
691 int usb_detect_change(void)
692 {
693 	struct udevice *hub;
694 	struct uclass *uc;
695 	int change = 0;
696 	int ret;
697 
698 	ret = uclass_get(UCLASS_USB_HUB, &uc);
699 	if (ret)
700 		return ret;
701 
702 	uclass_foreach_dev(hub, uc) {
703 		struct usb_device *udev;
704 		struct udevice *dev;
705 
706 		if (!device_active(hub))
707 			continue;
708 		for (device_find_first_child(hub, &dev);
709 		     dev;
710 		     device_find_next_child(&dev)) {
711 			struct usb_port_status status;
712 
713 			if (!device_active(dev))
714 				continue;
715 
716 			udev = dev_get_parent_priv(dev);
717 			if (usb_get_port_status(udev, udev->portnr, &status)
718 					< 0)
719 				/* USB request failed */
720 				continue;
721 
722 			if (le16_to_cpu(status.wPortChange) &
723 			    USB_PORT_STAT_C_CONNECTION)
724 				change++;
725 		}
726 	}
727 
728 	return change;
729 }
730 
731 static int usb_child_post_bind(struct udevice *dev)
732 {
733 	struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
734 	int val;
735 
736 	if (!dev_of_valid(dev))
737 		return 0;
738 
739 	/* We only support matching a few things */
740 	val = dev_read_u32_default(dev, "usb,device-class", -1);
741 	if (val != -1) {
742 		plat->id.match_flags |= USB_DEVICE_ID_MATCH_DEV_CLASS;
743 		plat->id.bDeviceClass = val;
744 	}
745 	val = dev_read_u32_default(dev, "usb,interface-class", -1);
746 	if (val != -1) {
747 		plat->id.match_flags |= USB_DEVICE_ID_MATCH_INT_CLASS;
748 		plat->id.bInterfaceClass = val;
749 	}
750 
751 	return 0;
752 }
753 
754 struct udevice *usb_get_bus(struct udevice *dev)
755 {
756 	struct udevice *bus;
757 
758 	for (bus = dev; bus && device_get_uclass_id(bus) != UCLASS_USB; )
759 		bus = bus->parent;
760 	if (!bus) {
761 		/* By design this cannot happen */
762 		assert(bus);
763 		debug("USB HUB '%s' does not have a controller\n", dev->name);
764 	}
765 
766 	return bus;
767 }
768 
769 int usb_child_pre_probe(struct udevice *dev)
770 {
771 	struct usb_device *udev = dev_get_parent_priv(dev);
772 	struct usb_dev_platdata *plat = dev_get_parent_platdata(dev);
773 	int ret;
774 
775 	if (plat->udev) {
776 		/*
777 		 * Copy over all the values set in the on stack struct
778 		 * usb_device in usb_scan_device() to our final struct
779 		 * usb_device for this dev.
780 		 */
781 		*udev = *(plat->udev);
782 		/* And clear plat->udev as it will not be valid for long */
783 		plat->udev = NULL;
784 		udev->dev = dev;
785 	} else {
786 		/*
787 		 * This happens with devices which are explicitly bound
788 		 * instead of being discovered through usb_scan_device()
789 		 * such as sandbox emul devices.
790 		 */
791 		udev->dev = dev;
792 		udev->controller_dev = usb_get_bus(dev);
793 		udev->devnum = plat->devnum;
794 
795 		/*
796 		 * udev did not go through usb_scan_device(), so we need to
797 		 * select the config and read the config descriptors.
798 		 */
799 		ret = usb_select_config(udev);
800 		if (ret)
801 			return ret;
802 	}
803 
804 	return 0;
805 }
806 
807 UCLASS_DRIVER(usb) = {
808 	.id		= UCLASS_USB,
809 	.name		= "usb",
810 	.flags		= DM_UC_FLAG_SEQ_ALIAS,
811 	.post_bind	= dm_scan_fdt_dev,
812 	.priv_auto_alloc_size = sizeof(struct usb_uclass_priv),
813 	.per_child_auto_alloc_size = sizeof(struct usb_device),
814 	.per_device_auto_alloc_size = sizeof(struct usb_bus_priv),
815 	.child_post_bind = usb_child_post_bind,
816 	.child_pre_probe = usb_child_pre_probe,
817 	.per_child_platdata_auto_alloc_size = sizeof(struct usb_dev_platdata),
818 };
819 
820 UCLASS_DRIVER(usb_dev_generic) = {
821 	.id		= UCLASS_USB_DEV_GENERIC,
822 	.name		= "usb_dev_generic",
823 };
824 
825 U_BOOT_DRIVER(usb_dev_generic_drv) = {
826 	.id		= UCLASS_USB_DEV_GENERIC,
827 	.name		= "usb_dev_generic_drv",
828 };
829