xref: /rk3399_rockchip-uboot/common/usb_hub.c (revision 78abf14fc2ff577d0385f36fe91769d458fbc4a5)
1 /*
2  * Most of this source has been derived from the Linux USB
3  * project:
4  * (C) Copyright Linus Torvalds 1999
5  * (C) Copyright Johannes Erdfelt 1999-2001
6  * (C) Copyright Andreas Gal 1999
7  * (C) Copyright Gregory P. Smith 1999
8  * (C) Copyright Deti Fliegl 1999 (new USB architecture)
9  * (C) Copyright Randy Dunlap 2000
10  * (C) Copyright David Brownell 2000 (kernel hotplug, usb_device_id)
11  * (C) Copyright Yggdrasil Computing, Inc. 2000
12  *     (usb_device_id matching changes by Adam J. Richter)
13  *
14  * Adapted for U-Boot:
15  * (C) Copyright 2001 Denis Peter, MPL AG Switzerland
16  *
17  * SPDX-License-Identifier:	GPL-2.0+
18  */
19 
20 /****************************************************************************
21  * HUB "Driver"
22  * Probes device for being a hub and configurate it
23  */
24 
25 #include <common.h>
26 #include <command.h>
27 #include <dm.h>
28 #include <errno.h>
29 #include <memalign.h>
30 #include <asm/processor.h>
31 #include <asm/unaligned.h>
32 #include <linux/ctype.h>
33 #include <linux/list.h>
34 #include <asm/byteorder.h>
35 #ifdef CONFIG_SANDBOX
36 #include <asm/state.h>
37 #endif
38 #include <asm/unaligned.h>
39 
40 DECLARE_GLOBAL_DATA_PTR;
41 
42 #include <usb.h>
43 
44 #define USB_BUFSIZ	512
45 
46 #define HUB_SHORT_RESET_TIME	20
47 #define HUB_LONG_RESET_TIME	200
48 
49 #define PORT_OVERCURRENT_MAX_SCAN_COUNT		3
50 
51 struct usb_device_scan {
52 	struct usb_device *dev;		/* USB hub device to scan */
53 	struct usb_hub_device *hub;	/* USB hub struct */
54 	int port;			/* USB port to scan */
55 	struct list_head list;
56 };
57 
58 /* TODO(sjg@chromium.org): Remove this when CONFIG_DM_USB is defined */
59 static struct usb_hub_device hub_dev[USB_MAX_HUB];
60 static int usb_hub_index;
61 static LIST_HEAD(usb_scan_list);
62 
63 __weak void usb_hub_reset_devices(int port)
64 {
65 	return;
66 }
67 
68 static inline bool usb_hub_is_superspeed(struct usb_device *hdev)
69 {
70 	return hdev->descriptor.bDeviceProtocol == 3;
71 }
72 
73 static int usb_get_hub_descriptor(struct usb_device *dev, void *data, int size)
74 {
75 	unsigned short dtype = USB_DT_HUB;
76 
77 	if (usb_hub_is_superspeed(dev))
78 		dtype = USB_DT_SS_HUB;
79 
80 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
81 		USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
82 		dtype << 8, 0, data, size, USB_CNTL_TIMEOUT);
83 }
84 
85 static int usb_clear_port_feature(struct usb_device *dev, int port, int feature)
86 {
87 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
88 				USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature,
89 				port, NULL, 0, USB_CNTL_TIMEOUT);
90 }
91 
92 static int usb_set_port_feature(struct usb_device *dev, int port, int feature)
93 {
94 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
95 				USB_REQ_SET_FEATURE, USB_RT_PORT, feature,
96 				port, NULL, 0, USB_CNTL_TIMEOUT);
97 }
98 
99 static int usb_get_hub_status(struct usb_device *dev, void *data)
100 {
101 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
102 			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
103 			data, sizeof(struct usb_hub_status), USB_CNTL_TIMEOUT);
104 }
105 
106 int usb_get_port_status(struct usb_device *dev, int port, void *data)
107 {
108 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
109 			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port,
110 			data, sizeof(struct usb_port_status), USB_CNTL_TIMEOUT);
111 }
112 
113 
114 static void usb_hub_power_on(struct usb_hub_device *hub)
115 {
116 	int i;
117 	struct usb_device *dev;
118 	unsigned pgood_delay = hub->desc.bPwrOn2PwrGood * 2;
119 	const char *env;
120 
121 	dev = hub->pusb_dev;
122 
123 	debug("enabling power on all ports\n");
124 	for (i = 0; i < dev->maxchild; i++) {
125 		usb_set_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
126 		debug("port %d returns %lX\n", i + 1, dev->status);
127 	}
128 
129 #ifdef CONFIG_SANDBOX
130 	/*
131 	 * Don't set timeout / delay values here. This results
132 	 * in these values still being reset to 0.
133 	 */
134 	if (state_get_skip_delays())
135 		return;
136 #endif
137 
138 	/*
139 	 * Wait for power to become stable,
140 	 * plus spec-defined max time for device to connect
141 	 * but allow this time to be increased via env variable as some
142 	 * devices break the spec and require longer warm-up times
143 	 */
144 	env = getenv("usb_pgood_delay");
145 	if (env)
146 		pgood_delay = max(pgood_delay,
147 			          (unsigned)simple_strtol(env, NULL, 0));
148 	debug("pgood_delay=%dms\n", pgood_delay);
149 
150 	/*
151 	 * Do a minimum delay of the larger value of 100ms or pgood_delay
152 	 * so that the power can stablize before the devices are queried
153 	 */
154 	hub->query_delay = get_timer(0) + max(100, (int)pgood_delay);
155 
156 	/*
157 	 * Record the power-on timeout here. The max. delay (timeout)
158 	 * will be done based on this value in the USB port loop in
159 	 * usb_hub_configure() later.
160 	 */
161 	hub->connect_timeout = hub->query_delay + 1000;
162 	debug("devnum=%d poweron: query_delay=%d connect_timeout=%d\n",
163 	      dev->devnum, max(100, (int)pgood_delay),
164 	      max(100, (int)pgood_delay) + 1000);
165 }
166 
167 void usb_hub_reset(void)
168 {
169 	usb_hub_index = 0;
170 
171 	/* Zero out global hub_dev in case its re-used again */
172 	memset(hub_dev, 0, sizeof(hub_dev));
173 }
174 
175 static struct usb_hub_device *usb_hub_allocate(void)
176 {
177 	if (usb_hub_index < USB_MAX_HUB)
178 		return &hub_dev[usb_hub_index++];
179 
180 	printf("ERROR: USB_MAX_HUB (%d) reached\n", USB_MAX_HUB);
181 	return NULL;
182 }
183 
184 #define MAX_TRIES 5
185 
186 static inline char *portspeed(int portstatus)
187 {
188 	char *speed_str;
189 
190 	switch (portstatus & USB_PORT_STAT_SPEED_MASK) {
191 	case USB_PORT_STAT_SUPER_SPEED:
192 		speed_str = "5 Gb/s";
193 		break;
194 	case USB_PORT_STAT_HIGH_SPEED:
195 		speed_str = "480 Mb/s";
196 		break;
197 	case USB_PORT_STAT_LOW_SPEED:
198 		speed_str = "1.5 Mb/s";
199 		break;
200 	default:
201 		speed_str = "12 Mb/s";
202 		break;
203 	}
204 
205 	return speed_str;
206 }
207 
208 int legacy_hub_port_reset(struct usb_device *dev, int port,
209 			unsigned short *portstat)
210 {
211 	int err, tries;
212 	ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
213 	unsigned short portstatus, portchange;
214 	int delay = HUB_SHORT_RESET_TIME; /* start with short reset delay */
215 
216 #ifdef CONFIG_DM_USB
217 	debug("%s: resetting '%s' port %d...\n", __func__, dev->dev->name,
218 	      port + 1);
219 #else
220 	debug("%s: resetting port %d...\n", __func__, port + 1);
221 #endif
222 	for (tries = 0; tries < MAX_TRIES; tries++) {
223 		err = usb_set_port_feature(dev, port + 1, USB_PORT_FEAT_RESET);
224 		if (err < 0)
225 			return err;
226 
227 		mdelay(delay);
228 
229 		if (usb_get_port_status(dev, port + 1, portsts) < 0) {
230 			debug("get_port_status failed status %lX\n",
231 			      dev->status);
232 			return -1;
233 		}
234 		portstatus = le16_to_cpu(portsts->wPortStatus);
235 		portchange = le16_to_cpu(portsts->wPortChange);
236 
237 		debug("portstatus %x, change %x, %s\n", portstatus, portchange,
238 							portspeed(portstatus));
239 
240 		debug("STAT_C_CONNECTION = %d STAT_CONNECTION = %d" \
241 		      "  USB_PORT_STAT_ENABLE %d\n",
242 		      (portchange & USB_PORT_STAT_C_CONNECTION) ? 1 : 0,
243 		      (portstatus & USB_PORT_STAT_CONNECTION) ? 1 : 0,
244 		      (portstatus & USB_PORT_STAT_ENABLE) ? 1 : 0);
245 
246 		/*
247 		 * Perhaps we should check for the following here:
248 		 * - C_CONNECTION hasn't been set.
249 		 * - CONNECTION is still set.
250 		 *
251 		 * Doing so would ensure that the device is still connected
252 		 * to the bus, and hasn't been unplugged or replaced while the
253 		 * USB bus reset was going on.
254 		 *
255 		 * However, if we do that, then (at least) a San Disk Ultra
256 		 * USB 3.0 16GB device fails to reset on (at least) an NVIDIA
257 		 * Tegra Jetson TK1 board. For some reason, the device appears
258 		 * to briefly drop off the bus when this second bus reset is
259 		 * executed, yet if we retry this loop, it'll eventually come
260 		 * back after another reset or two.
261 		 */
262 
263 		if (portstatus & USB_PORT_STAT_ENABLE)
264 			break;
265 
266 		/* Switch to long reset delay for the next round */
267 		delay = HUB_LONG_RESET_TIME;
268 	}
269 
270 	if (tries == MAX_TRIES) {
271 		debug("Cannot enable port %i after %i retries, " \
272 		      "disabling port.\n", port + 1, MAX_TRIES);
273 		debug("Maybe the USB cable is bad?\n");
274 		return -1;
275 	}
276 
277 	usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_C_RESET);
278 	*portstat = portstatus;
279 	return 0;
280 }
281 
282 #ifdef CONFIG_DM_USB
283 int hub_port_reset(struct udevice *dev, int port, unsigned short *portstat)
284 {
285 	struct usb_device *udev = dev_get_parent_priv(dev);
286 
287 	return legacy_hub_port_reset(udev, port, portstat);
288 }
289 #endif
290 
291 int usb_hub_port_connect_change(struct usb_device *dev, int port)
292 {
293 	ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
294 	unsigned short portstatus;
295 	int ret, speed;
296 
297 	/* Check status */
298 	ret = usb_get_port_status(dev, port + 1, portsts);
299 	if (ret < 0) {
300 		debug("get_port_status failed\n");
301 		return ret;
302 	}
303 
304 	portstatus = le16_to_cpu(portsts->wPortStatus);
305 	debug("portstatus %x, change %x, %s\n",
306 	      portstatus,
307 	      le16_to_cpu(portsts->wPortChange),
308 	      portspeed(portstatus));
309 
310 	/* Clear the connection change status */
311 	usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_C_CONNECTION);
312 
313 	/* Disconnect any existing devices under this port */
314 	if (((!(portstatus & USB_PORT_STAT_CONNECTION)) &&
315 	     (!(portstatus & USB_PORT_STAT_ENABLE))) ||
316 	    usb_device_has_child_on_port(dev, port)) {
317 		debug("usb_disconnect(&hub->children[port]);\n");
318 		/* Return now if nothing is connected */
319 		if (!(portstatus & USB_PORT_STAT_CONNECTION))
320 			return -ENOTCONN;
321 	}
322 
323 	/* Reset the port */
324 	ret = legacy_hub_port_reset(dev, port, &portstatus);
325 	if (ret < 0) {
326 		if (ret != -ENXIO)
327 			printf("cannot reset port %i!?\n", port + 1);
328 		return ret;
329 	}
330 
331 	switch (portstatus & USB_PORT_STAT_SPEED_MASK) {
332 	case USB_PORT_STAT_SUPER_SPEED:
333 		speed = USB_SPEED_SUPER;
334 		break;
335 	case USB_PORT_STAT_HIGH_SPEED:
336 		speed = USB_SPEED_HIGH;
337 		break;
338 	case USB_PORT_STAT_LOW_SPEED:
339 		speed = USB_SPEED_LOW;
340 		break;
341 	default:
342 		speed = USB_SPEED_FULL;
343 		break;
344 	}
345 
346 #ifdef CONFIG_DM_USB
347 	struct udevice *child;
348 
349 	ret = usb_scan_device(dev->dev, port + 1, speed, &child);
350 #else
351 	struct usb_device *usb;
352 
353 	ret = usb_alloc_new_device(dev->controller, &usb);
354 	if (ret) {
355 		printf("cannot create new device: ret=%d", ret);
356 		return ret;
357 	}
358 
359 	dev->children[port] = usb;
360 	usb->speed = speed;
361 	usb->parent = dev;
362 	usb->portnr = port + 1;
363 	/* Run it through the hoops (find a driver, etc) */
364 	ret = usb_new_device(usb);
365 	if (ret < 0) {
366 		/* Woops, disable the port */
367 		usb_free_device(dev->controller);
368 		dev->children[port] = NULL;
369 	}
370 #endif
371 	if (ret < 0) {
372 		debug("hub: disabling port %d\n", port + 1);
373 		usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_ENABLE);
374 	}
375 
376 	return ret;
377 }
378 
379 static int usb_scan_port(struct usb_device_scan *usb_scan)
380 {
381 	ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
382 	unsigned short portstatus;
383 	unsigned short portchange;
384 	struct usb_device *dev;
385 	struct usb_hub_device *hub;
386 	int ret = 0;
387 	int i;
388 
389 	dev = usb_scan->dev;
390 	hub = usb_scan->hub;
391 	i = usb_scan->port;
392 
393 	/*
394 	 * Don't talk to the device before the query delay is expired.
395 	 * This is needed for voltages to stabalize.
396 	 */
397 	if (get_timer(0) < hub->query_delay)
398 		return 0;
399 
400 	ret = usb_get_port_status(dev, i + 1, portsts);
401 	if (ret < 0) {
402 		debug("get_port_status failed\n");
403 		if (get_timer(0) >= hub->connect_timeout) {
404 			debug("devnum=%d port=%d: timeout\n",
405 			      dev->devnum, i + 1);
406 			/* Remove this device from scanning list */
407 			list_del(&usb_scan->list);
408 			free(usb_scan);
409 			return 0;
410 		}
411 		return 0;
412 	}
413 
414 	portstatus = le16_to_cpu(portsts->wPortStatus);
415 	portchange = le16_to_cpu(portsts->wPortChange);
416 	debug("Port %d Status %X Change %X\n", i + 1, portstatus, portchange);
417 
418 	/*
419 	 * No connection change happened, wait a bit more.
420 	 *
421 	 * For some situation, the hub reports no connection change but a
422 	 * device is connected to the port (eg: CCS bit is set but CSC is not
423 	 * in the PORTSC register of a root hub), ignore such case.
424 	 */
425 	if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
426 	    !(portstatus & USB_PORT_STAT_CONNECTION)) {
427 		if (get_timer(0) >= hub->connect_timeout) {
428 			debug("devnum=%d port=%d: timeout\n",
429 			      dev->devnum, i + 1);
430 			/* Remove this device from scanning list */
431 			list_del(&usb_scan->list);
432 			free(usb_scan);
433 			return 0;
434 		}
435 		return 0;
436 	}
437 
438 	/* A new USB device is ready at this point */
439 	debug("devnum=%d port=%d: USB dev found\n", dev->devnum, i + 1);
440 
441 	usb_hub_port_connect_change(dev, i);
442 
443 	if (portchange & USB_PORT_STAT_C_ENABLE) {
444 		debug("port %d enable change, status %x\n", i + 1, portstatus);
445 		usb_clear_port_feature(dev, i + 1, USB_PORT_FEAT_C_ENABLE);
446 		/*
447 		 * The following hack causes a ghost device problem
448 		 * to Faraday EHCI
449 		 */
450 #ifndef CONFIG_USB_EHCI_FARADAY
451 		/*
452 		 * EM interference sometimes causes bad shielded USB
453 		 * devices to be shutdown by the hub, this hack enables
454 		 * them again. Works at least with mouse driver
455 		 */
456 		if (!(portstatus & USB_PORT_STAT_ENABLE) &&
457 		    (portstatus & USB_PORT_STAT_CONNECTION) &&
458 		    usb_device_has_child_on_port(dev, i)) {
459 			debug("already running port %i disabled by hub (EMI?), re-enabling...\n",
460 			      i + 1);
461 			usb_hub_port_connect_change(dev, i);
462 		}
463 #endif
464 	}
465 
466 	if (portstatus & USB_PORT_STAT_SUSPEND) {
467 		debug("port %d suspend change\n", i + 1);
468 		usb_clear_port_feature(dev, i + 1, USB_PORT_FEAT_SUSPEND);
469 	}
470 
471 	if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
472 		debug("port %d over-current change\n", i + 1);
473 		usb_clear_port_feature(dev, i + 1,
474 				       USB_PORT_FEAT_C_OVER_CURRENT);
475 		/* Only power-on this one port */
476 		usb_set_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
477 		hub->overcurrent_count[i]++;
478 
479 		/*
480 		 * If the max-scan-count is not reached, return without removing
481 		 * the device from scan-list. This will re-issue a new scan.
482 		 */
483 		if (hub->overcurrent_count[i] <=
484 		    PORT_OVERCURRENT_MAX_SCAN_COUNT)
485 			return 0;
486 
487 		/* Otherwise the device will get removed */
488 		printf("Port %d over-current occurred %d times\n", i + 1,
489 		       hub->overcurrent_count[i]);
490 	}
491 
492 	if (portchange & USB_PORT_STAT_C_RESET) {
493 		debug("port %d reset change\n", i + 1);
494 		usb_clear_port_feature(dev, i + 1, USB_PORT_FEAT_C_RESET);
495 	}
496 
497 	/*
498 	 * We're done with this device, so let's remove this device from
499 	 * scanning list
500 	 */
501 	list_del(&usb_scan->list);
502 	free(usb_scan);
503 
504 	return 0;
505 }
506 
507 static int usb_device_list_scan(void)
508 {
509 	struct usb_device_scan *usb_scan;
510 	struct usb_device_scan *tmp;
511 	static int running;
512 	int ret = 0;
513 
514 	/* Only run this loop once for each controller */
515 	if (running)
516 		return 0;
517 
518 	running = 1;
519 
520 	while (1) {
521 		/* We're done, once the list is empty again */
522 		if (list_empty(&usb_scan_list))
523 			goto out;
524 
525 		list_for_each_entry_safe(usb_scan, tmp, &usb_scan_list, list) {
526 			int ret;
527 
528 			/* Scan this port */
529 			ret = usb_scan_port(usb_scan);
530 			if (ret)
531 				goto out;
532 		}
533 	}
534 
535 out:
536 	/*
537 	 * This USB controller has finished scanning all its connected
538 	 * USB devices. Set "running" back to 0, so that other USB controllers
539 	 * will scan their devices too.
540 	 */
541 	running = 0;
542 
543 	return ret;
544 }
545 
546 static int usb_hub_configure(struct usb_device *dev)
547 {
548 	int i, length;
549 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, USB_BUFSIZ);
550 	unsigned char *bitmap;
551 	short hubCharacteristics;
552 	struct usb_hub_descriptor *descriptor;
553 	struct usb_hub_device *hub;
554 	__maybe_unused struct usb_hub_status *hubsts;
555 	int ret;
556 
557 	/* "allocate" Hub device */
558 	hub = usb_hub_allocate();
559 	if (hub == NULL)
560 		return -ENOMEM;
561 	hub->pusb_dev = dev;
562 	/* Get the the hub descriptor */
563 	ret = usb_get_hub_descriptor(dev, buffer, 4);
564 	if (ret < 0) {
565 		debug("usb_hub_configure: failed to get hub " \
566 		      "descriptor, giving up %lX\n", dev->status);
567 		return ret;
568 	}
569 	descriptor = (struct usb_hub_descriptor *)buffer;
570 
571 	length = min_t(int, descriptor->bLength,
572 		       sizeof(struct usb_hub_descriptor));
573 
574 	ret = usb_get_hub_descriptor(dev, buffer, length);
575 	if (ret < 0) {
576 		debug("usb_hub_configure: failed to get hub " \
577 		      "descriptor 2nd giving up %lX\n", dev->status);
578 		return ret;
579 	}
580 	memcpy((unsigned char *)&hub->desc, buffer, length);
581 	/* adjust 16bit values */
582 	put_unaligned(le16_to_cpu(get_unaligned(
583 			&descriptor->wHubCharacteristics)),
584 			&hub->desc.wHubCharacteristics);
585 	/* set the bitmap */
586 	bitmap = (unsigned char *)&hub->desc.u.hs.DeviceRemovable[0];
587 	/* devices not removable by default */
588 	memset(bitmap, 0xff, (USB_MAXCHILDREN+1+7)/8);
589 	bitmap = (unsigned char *)&hub->desc.u.hs.PortPowerCtrlMask[0];
590 	memset(bitmap, 0xff, (USB_MAXCHILDREN+1+7)/8); /* PowerMask = 1B */
591 
592 	for (i = 0; i < ((hub->desc.bNbrPorts + 1 + 7)/8); i++)
593 		hub->desc.u.hs.DeviceRemovable[i] =
594 			descriptor->u.hs.DeviceRemovable[i];
595 
596 	for (i = 0; i < ((hub->desc.bNbrPorts + 1 + 7)/8); i++)
597 		hub->desc.u.hs.PortPowerCtrlMask[i] =
598 			descriptor->u.hs.PortPowerCtrlMask[i];
599 
600 	dev->maxchild = descriptor->bNbrPorts;
601 	debug("%d ports detected\n", dev->maxchild);
602 
603 	hubCharacteristics = get_unaligned(&hub->desc.wHubCharacteristics);
604 	switch (hubCharacteristics & HUB_CHAR_LPSM) {
605 	case 0x00:
606 		debug("ganged power switching\n");
607 		break;
608 	case 0x01:
609 		debug("individual port power switching\n");
610 		break;
611 	case 0x02:
612 	case 0x03:
613 		debug("unknown reserved power switching mode\n");
614 		break;
615 	}
616 
617 	if (hubCharacteristics & HUB_CHAR_COMPOUND)
618 		debug("part of a compound device\n");
619 	else
620 		debug("standalone hub\n");
621 
622 	switch (hubCharacteristics & HUB_CHAR_OCPM) {
623 	case 0x00:
624 		debug("global over-current protection\n");
625 		break;
626 	case 0x08:
627 		debug("individual port over-current protection\n");
628 		break;
629 	case 0x10:
630 	case 0x18:
631 		debug("no over-current protection\n");
632 		break;
633 	}
634 
635 	debug("power on to power good time: %dms\n",
636 	      descriptor->bPwrOn2PwrGood * 2);
637 	debug("hub controller current requirement: %dmA\n",
638 	      descriptor->bHubContrCurrent);
639 
640 	for (i = 0; i < dev->maxchild; i++)
641 		debug("port %d is%s removable\n", i + 1,
642 		      hub->desc.u.hs.DeviceRemovable[(i + 1) / 8] & \
643 		      (1 << ((i + 1) % 8)) ? " not" : "");
644 
645 	if (sizeof(struct usb_hub_status) > USB_BUFSIZ) {
646 		debug("usb_hub_configure: failed to get Status - " \
647 		      "too long: %d\n", descriptor->bLength);
648 		return -EFBIG;
649 	}
650 
651 	ret = usb_get_hub_status(dev, buffer);
652 	if (ret < 0) {
653 		debug("usb_hub_configure: failed to get Status %lX\n",
654 		      dev->status);
655 		return ret;
656 	}
657 
658 #ifdef DEBUG
659 	hubsts = (struct usb_hub_status *)buffer;
660 #endif
661 
662 	debug("get_hub_status returned status %X, change %X\n",
663 	      le16_to_cpu(hubsts->wHubStatus),
664 	      le16_to_cpu(hubsts->wHubChange));
665 	debug("local power source is %s\n",
666 	      (le16_to_cpu(hubsts->wHubStatus) & HUB_STATUS_LOCAL_POWER) ? \
667 	      "lost (inactive)" : "good");
668 	debug("%sover-current condition exists\n",
669 	      (le16_to_cpu(hubsts->wHubStatus) & HUB_STATUS_OVERCURRENT) ? \
670 	      "" : "no ");
671 	usb_hub_power_on(hub);
672 
673 	/*
674 	 * Reset any devices that may be in a bad state when applying
675 	 * the power.  This is a __weak function.  Resetting of the devices
676 	 * should occur in the board file of the device.
677 	 */
678 	for (i = 0; i < dev->maxchild; i++)
679 		usb_hub_reset_devices(i + 1);
680 
681 	/*
682 	 * Only add the connected USB devices, including potential hubs,
683 	 * to a scanning list. This list will get scanned and devices that
684 	 * are detected (either via port connected or via port timeout)
685 	 * will get removed from this list. Scanning of the devices on this
686 	 * list will continue until all devices are removed.
687 	 */
688 	for (i = 0; i < dev->maxchild; i++) {
689 		struct usb_device_scan *usb_scan;
690 
691 		usb_scan = calloc(1, sizeof(*usb_scan));
692 		if (!usb_scan) {
693 			printf("Can't allocate memory for USB device!\n");
694 			return -ENOMEM;
695 		}
696 		usb_scan->dev = dev;
697 		usb_scan->hub = hub;
698 		usb_scan->port = i;
699 		list_add_tail(&usb_scan->list, &usb_scan_list);
700 	}
701 
702 	/*
703 	 * And now call the scanning code which loops over the generated list
704 	 */
705 	ret = usb_device_list_scan();
706 
707 	return ret;
708 }
709 
710 static int usb_hub_check(struct usb_device *dev, int ifnum)
711 {
712 	struct usb_interface *iface;
713 	struct usb_endpoint_descriptor *ep = NULL;
714 
715 	iface = &dev->config.if_desc[ifnum];
716 	/* Is it a hub? */
717 	if (iface->desc.bInterfaceClass != USB_CLASS_HUB)
718 		goto err;
719 	/* Some hubs have a subclass of 1, which AFAICT according to the */
720 	/*  specs is not defined, but it works */
721 	if ((iface->desc.bInterfaceSubClass != 0) &&
722 	    (iface->desc.bInterfaceSubClass != 1))
723 		goto err;
724 	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
725 	if (iface->desc.bNumEndpoints != 1)
726 		goto err;
727 	ep = &iface->ep_desc[0];
728 	/* Output endpoint? Curiousier and curiousier.. */
729 	if (!(ep->bEndpointAddress & USB_DIR_IN))
730 		goto err;
731 	/* If it's not an interrupt endpoint, we'd better punt! */
732 	if ((ep->bmAttributes & 3) != 3)
733 		goto err;
734 	/* We found a hub */
735 	debug("USB hub found\n");
736 	return 0;
737 
738 err:
739 	debug("USB hub not found: bInterfaceClass=%d, bInterfaceSubClass=%d, bNumEndpoints=%d\n",
740 	      iface->desc.bInterfaceClass, iface->desc.bInterfaceSubClass,
741 	      iface->desc.bNumEndpoints);
742 	if (ep) {
743 		debug("   bEndpointAddress=%#x, bmAttributes=%d",
744 		      ep->bEndpointAddress, ep->bmAttributes);
745 	}
746 
747 	return -ENOENT;
748 }
749 
750 int usb_hub_probe(struct usb_device *dev, int ifnum)
751 {
752 	int ret;
753 
754 	ret = usb_hub_check(dev, ifnum);
755 	if (ret)
756 		return 0;
757 	ret = usb_hub_configure(dev);
758 	return ret;
759 }
760 
761 #ifdef CONFIG_DM_USB
762 int usb_hub_scan(struct udevice *hub)
763 {
764 	struct usb_device *udev = dev_get_parent_priv(hub);
765 
766 	return usb_hub_configure(udev);
767 }
768 
769 static int usb_hub_post_probe(struct udevice *dev)
770 {
771 	debug("%s\n", __func__);
772 	return usb_hub_scan(dev);
773 }
774 
775 static const struct udevice_id usb_hub_ids[] = {
776 	{ .compatible = "usb-hub" },
777 	{ }
778 };
779 
780 U_BOOT_DRIVER(usb_generic_hub) = {
781 	.name	= "usb_hub",
782 	.id	= UCLASS_USB_HUB,
783 	.of_match = usb_hub_ids,
784 	.flags	= DM_FLAG_ALLOC_PRIV_DMA,
785 };
786 
787 UCLASS_DRIVER(usb_hub) = {
788 	.id		= UCLASS_USB_HUB,
789 	.name		= "usb_hub",
790 	.post_bind	= dm_scan_fdt_dev,
791 	.post_probe	= usb_hub_post_probe,
792 	.child_pre_probe	= usb_child_pre_probe,
793 	.per_child_auto_alloc_size = sizeof(struct usb_device),
794 	.per_child_platdata_auto_alloc_size = sizeof(struct usb_dev_platdata),
795 };
796 
797 static const struct usb_device_id hub_id_table[] = {
798 	{
799 		.match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
800 		.bDeviceClass = USB_CLASS_HUB
801 	},
802 	{ }	/* Terminating entry */
803 };
804 
805 U_BOOT_USB_DEVICE(usb_generic_hub, hub_id_table);
806 
807 #endif
808