xref: /openbmc/u-boot/common/usb_hub.c (revision e8f80a5a)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Most of this source has been derived from the Linux USB
4  * project:
5  * (C) Copyright Linus Torvalds 1999
6  * (C) Copyright Johannes Erdfelt 1999-2001
7  * (C) Copyright Andreas Gal 1999
8  * (C) Copyright Gregory P. Smith 1999
9  * (C) Copyright Deti Fliegl 1999 (new USB architecture)
10  * (C) Copyright Randy Dunlap 2000
11  * (C) Copyright David Brownell 2000 (kernel hotplug, usb_device_id)
12  * (C) Copyright Yggdrasil Computing, Inc. 2000
13  *     (usb_device_id matching changes by Adam J. Richter)
14  *
15  * Adapted for U-Boot:
16  * (C) Copyright 2001 Denis Peter, MPL AG Switzerland
17  */
18 
19 /****************************************************************************
20  * HUB "Driver"
21  * Probes device for being a hub and configurate it
22  */
23 
24 #include <common.h>
25 #include <command.h>
26 #include <dm.h>
27 #include <errno.h>
28 #include <memalign.h>
29 #include <asm/processor.h>
30 #include <asm/unaligned.h>
31 #include <linux/ctype.h>
32 #include <linux/list.h>
33 #include <asm/byteorder.h>
34 #ifdef CONFIG_SANDBOX
35 #include <asm/state.h>
36 #endif
37 #include <asm/unaligned.h>
38 
39 #include <usb.h>
40 
41 #define USB_BUFSIZ	512
42 
43 #define HUB_SHORT_RESET_TIME	20
44 #define HUB_LONG_RESET_TIME	200
45 
46 #define PORT_OVERCURRENT_MAX_SCAN_COUNT		3
47 
48 struct usb_device_scan {
49 	struct usb_device *dev;		/* USB hub device to scan */
50 	struct usb_hub_device *hub;	/* USB hub struct */
51 	int port;			/* USB port to scan */
52 	struct list_head list;
53 };
54 
55 static LIST_HEAD(usb_scan_list);
56 
57 __weak void usb_hub_reset_devices(struct usb_hub_device *hub, int port)
58 {
59 	return;
60 }
61 
62 static inline bool usb_hub_is_superspeed(struct usb_device *hdev)
63 {
64 	return hdev->descriptor.bDeviceProtocol == 3;
65 }
66 
67 #ifdef CONFIG_DM_USB
68 bool usb_hub_is_root_hub(struct udevice *hub)
69 {
70 	if (device_get_uclass_id(hub->parent) != UCLASS_USB_HUB)
71 		return true;
72 
73 	return false;
74 }
75 
76 static int usb_set_hub_depth(struct usb_device *dev, int depth)
77 {
78 	if (depth < 0 || depth > 4)
79 		return -EINVAL;
80 
81 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
82 		USB_REQ_SET_HUB_DEPTH, USB_DIR_OUT | USB_RT_HUB,
83 		depth, 0, NULL, 0, USB_CNTL_TIMEOUT);
84 }
85 #endif
86 
87 static int usb_get_hub_descriptor(struct usb_device *dev, void *data, int size)
88 {
89 	unsigned short dtype = USB_DT_HUB;
90 
91 	if (usb_hub_is_superspeed(dev))
92 		dtype = USB_DT_SS_HUB;
93 
94 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
95 		USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
96 		dtype << 8, 0, data, size, USB_CNTL_TIMEOUT);
97 }
98 
99 static int usb_clear_port_feature(struct usb_device *dev, int port, int feature)
100 {
101 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
102 				USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature,
103 				port, NULL, 0, USB_CNTL_TIMEOUT);
104 }
105 
106 static int usb_set_port_feature(struct usb_device *dev, int port, int feature)
107 {
108 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
109 				USB_REQ_SET_FEATURE, USB_RT_PORT, feature,
110 				port, NULL, 0, USB_CNTL_TIMEOUT);
111 }
112 
113 static int usb_get_hub_status(struct usb_device *dev, void *data)
114 {
115 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
116 			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
117 			data, sizeof(struct usb_hub_status), USB_CNTL_TIMEOUT);
118 }
119 
120 int usb_get_port_status(struct usb_device *dev, int port, void *data)
121 {
122 	int ret;
123 
124 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
125 			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port,
126 			data, sizeof(struct usb_port_status), USB_CNTL_TIMEOUT);
127 
128 #ifdef CONFIG_DM_USB
129 	if (ret < 0)
130 		return ret;
131 
132 	/*
133 	 * Translate the USB 3.0 hub port status field into the old version
134 	 * that U-Boot understands. Do this only when the hub is not root hub.
135 	 * For root hub, the port status field has already been translated
136 	 * in the host controller driver (see xhci_submit_root() in xhci.c).
137 	 *
138 	 * Note: this only supports driver model.
139 	 */
140 
141 	if (!usb_hub_is_root_hub(dev->dev) && usb_hub_is_superspeed(dev)) {
142 		struct usb_port_status *status = (struct usb_port_status *)data;
143 		u16 tmp = (status->wPortStatus) & USB_SS_PORT_STAT_MASK;
144 
145 		if (status->wPortStatus & USB_SS_PORT_STAT_POWER)
146 			tmp |= USB_PORT_STAT_POWER;
147 		if ((status->wPortStatus & USB_SS_PORT_STAT_SPEED) ==
148 		    USB_SS_PORT_STAT_SPEED_5GBPS)
149 			tmp |= USB_PORT_STAT_SUPER_SPEED;
150 
151 		status->wPortStatus = tmp;
152 	}
153 #endif
154 
155 	return ret;
156 }
157 
158 
159 static void usb_hub_power_on(struct usb_hub_device *hub)
160 {
161 	int i;
162 	struct usb_device *dev;
163 	unsigned pgood_delay = hub->desc.bPwrOn2PwrGood * 2;
164 	const char *env;
165 
166 	dev = hub->pusb_dev;
167 
168 	debug("enabling power on all ports\n");
169 	for (i = 0; i < dev->maxchild; i++) {
170 		usb_set_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
171 		debug("port %d returns %lX\n", i + 1, dev->status);
172 	}
173 
174 #ifdef CONFIG_SANDBOX
175 	/*
176 	 * Don't set timeout / delay values here. This results
177 	 * in these values still being reset to 0.
178 	 */
179 	if (state_get_skip_delays())
180 		return;
181 #endif
182 
183 	/*
184 	 * Wait for power to become stable,
185 	 * plus spec-defined max time for device to connect
186 	 * but allow this time to be increased via env variable as some
187 	 * devices break the spec and require longer warm-up times
188 	 */
189 	env = env_get("usb_pgood_delay");
190 	if (env)
191 		pgood_delay = max(pgood_delay,
192 			          (unsigned)simple_strtol(env, NULL, 0));
193 	debug("pgood_delay=%dms\n", pgood_delay);
194 
195 	/*
196 	 * Do a minimum delay of the larger value of 100ms or pgood_delay
197 	 * so that the power can stablize before the devices are queried
198 	 */
199 	hub->query_delay = get_timer(0) + max(100, (int)pgood_delay);
200 
201 	/*
202 	 * Record the power-on timeout here. The max. delay (timeout)
203 	 * will be done based on this value in the USB port loop in
204 	 * usb_hub_configure() later.
205 	 */
206 	hub->connect_timeout = hub->query_delay + 1000;
207 	debug("devnum=%d poweron: query_delay=%d connect_timeout=%d\n",
208 	      dev->devnum, max(100, (int)pgood_delay),
209 	      max(100, (int)pgood_delay) + 1000);
210 }
211 
212 #ifndef CONFIG_DM_USB
213 static struct usb_hub_device hub_dev[USB_MAX_HUB];
214 static int usb_hub_index;
215 
216 void usb_hub_reset(void)
217 {
218 	usb_hub_index = 0;
219 
220 	/* Zero out global hub_dev in case its re-used again */
221 	memset(hub_dev, 0, sizeof(hub_dev));
222 }
223 
224 static struct usb_hub_device *usb_hub_allocate(void)
225 {
226 	if (usb_hub_index < USB_MAX_HUB)
227 		return &hub_dev[usb_hub_index++];
228 
229 	printf("ERROR: USB_MAX_HUB (%d) reached\n", USB_MAX_HUB);
230 	return NULL;
231 }
232 #endif
233 
234 #define MAX_TRIES 5
235 
236 static inline char *portspeed(int portstatus)
237 {
238 	char *speed_str;
239 
240 	switch (portstatus & USB_PORT_STAT_SPEED_MASK) {
241 	case USB_PORT_STAT_SUPER_SPEED:
242 		speed_str = "5 Gb/s";
243 		break;
244 	case USB_PORT_STAT_HIGH_SPEED:
245 		speed_str = "480 Mb/s";
246 		break;
247 	case USB_PORT_STAT_LOW_SPEED:
248 		speed_str = "1.5 Mb/s";
249 		break;
250 	default:
251 		speed_str = "12 Mb/s";
252 		break;
253 	}
254 
255 	return speed_str;
256 }
257 
258 /**
259  * usb_hub_port_reset() - reset a port given its usb_device pointer
260  *
261  * Reset a hub port and see if a device is present on that port, providing
262  * sufficient time for it to show itself. The port status is returned.
263  *
264  * @dev:	USB device to reset
265  * @port:	Port number to reset (note ports are numbered from 0 here)
266  * @portstat:	Returns port status
267  */
268 static int usb_hub_port_reset(struct usb_device *dev, int port,
269 			      unsigned short *portstat)
270 {
271 	int err, tries;
272 	ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
273 	unsigned short portstatus, portchange;
274 	int delay = HUB_SHORT_RESET_TIME; /* start with short reset delay */
275 
276 #ifdef CONFIG_DM_USB
277 	debug("%s: resetting '%s' port %d...\n", __func__, dev->dev->name,
278 	      port + 1);
279 #else
280 	debug("%s: resetting port %d...\n", __func__, port + 1);
281 #endif
282 	for (tries = 0; tries < MAX_TRIES; tries++) {
283 		err = usb_set_port_feature(dev, port + 1, USB_PORT_FEAT_RESET);
284 		if (err < 0)
285 			return err;
286 
287 		mdelay(delay);
288 
289 		if (usb_get_port_status(dev, port + 1, portsts) < 0) {
290 			debug("get_port_status failed status %lX\n",
291 			      dev->status);
292 			return -1;
293 		}
294 		portstatus = le16_to_cpu(portsts->wPortStatus);
295 		portchange = le16_to_cpu(portsts->wPortChange);
296 
297 		debug("portstatus %x, change %x, %s\n", portstatus, portchange,
298 							portspeed(portstatus));
299 
300 		debug("STAT_C_CONNECTION = %d STAT_CONNECTION = %d" \
301 		      "  USB_PORT_STAT_ENABLE %d\n",
302 		      (portchange & USB_PORT_STAT_C_CONNECTION) ? 1 : 0,
303 		      (portstatus & USB_PORT_STAT_CONNECTION) ? 1 : 0,
304 		      (portstatus & USB_PORT_STAT_ENABLE) ? 1 : 0);
305 
306 		/*
307 		 * Perhaps we should check for the following here:
308 		 * - C_CONNECTION hasn't been set.
309 		 * - CONNECTION is still set.
310 		 *
311 		 * Doing so would ensure that the device is still connected
312 		 * to the bus, and hasn't been unplugged or replaced while the
313 		 * USB bus reset was going on.
314 		 *
315 		 * However, if we do that, then (at least) a San Disk Ultra
316 		 * USB 3.0 16GB device fails to reset on (at least) an NVIDIA
317 		 * Tegra Jetson TK1 board. For some reason, the device appears
318 		 * to briefly drop off the bus when this second bus reset is
319 		 * executed, yet if we retry this loop, it'll eventually come
320 		 * back after another reset or two.
321 		 */
322 
323 		if (portstatus & USB_PORT_STAT_ENABLE)
324 			break;
325 
326 		/* Switch to long reset delay for the next round */
327 		delay = HUB_LONG_RESET_TIME;
328 	}
329 
330 	if (tries == MAX_TRIES) {
331 		debug("Cannot enable port %i after %i retries, " \
332 		      "disabling port.\n", port + 1, MAX_TRIES);
333 		debug("Maybe the USB cable is bad?\n");
334 		return -1;
335 	}
336 
337 	usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_C_RESET);
338 	*portstat = portstatus;
339 	return 0;
340 }
341 
342 int usb_hub_port_connect_change(struct usb_device *dev, int port)
343 {
344 	ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
345 	unsigned short portstatus;
346 	int ret, speed;
347 
348 	/* Check status */
349 	ret = usb_get_port_status(dev, port + 1, portsts);
350 	if (ret < 0) {
351 		debug("get_port_status failed\n");
352 		return ret;
353 	}
354 
355 	portstatus = le16_to_cpu(portsts->wPortStatus);
356 	debug("portstatus %x, change %x, %s\n",
357 	      portstatus,
358 	      le16_to_cpu(portsts->wPortChange),
359 	      portspeed(portstatus));
360 
361 	/* Clear the connection change status */
362 	usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_C_CONNECTION);
363 
364 	/* Disconnect any existing devices under this port */
365 	if (((!(portstatus & USB_PORT_STAT_CONNECTION)) &&
366 	     (!(portstatus & USB_PORT_STAT_ENABLE))) ||
367 	    usb_device_has_child_on_port(dev, port)) {
368 		debug("usb_disconnect(&hub->children[port]);\n");
369 		/* Return now if nothing is connected */
370 		if (!(portstatus & USB_PORT_STAT_CONNECTION))
371 			return -ENOTCONN;
372 	}
373 
374 	/* Reset the port */
375 	ret = usb_hub_port_reset(dev, port, &portstatus);
376 	if (ret < 0) {
377 		if (ret != -ENXIO)
378 			printf("cannot reset port %i!?\n", port + 1);
379 		return ret;
380 	}
381 
382 	switch (portstatus & USB_PORT_STAT_SPEED_MASK) {
383 	case USB_PORT_STAT_SUPER_SPEED:
384 		speed = USB_SPEED_SUPER;
385 		break;
386 	case USB_PORT_STAT_HIGH_SPEED:
387 		speed = USB_SPEED_HIGH;
388 		break;
389 	case USB_PORT_STAT_LOW_SPEED:
390 		speed = USB_SPEED_LOW;
391 		break;
392 	default:
393 		speed = USB_SPEED_FULL;
394 		break;
395 	}
396 
397 #ifdef CONFIG_DM_USB
398 	struct udevice *child;
399 
400 	ret = usb_scan_device(dev->dev, port + 1, speed, &child);
401 #else
402 	struct usb_device *usb;
403 
404 	ret = usb_alloc_new_device(dev->controller, &usb);
405 	if (ret) {
406 		printf("cannot create new device: ret=%d", ret);
407 		return ret;
408 	}
409 
410 	dev->children[port] = usb;
411 	usb->speed = speed;
412 	usb->parent = dev;
413 	usb->portnr = port + 1;
414 	/* Run it through the hoops (find a driver, etc) */
415 	ret = usb_new_device(usb);
416 	if (ret < 0) {
417 		/* Woops, disable the port */
418 		usb_free_device(dev->controller);
419 		dev->children[port] = NULL;
420 	}
421 #endif
422 	if (ret < 0) {
423 		debug("hub: disabling port %d\n", port + 1);
424 		usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_ENABLE);
425 	}
426 
427 	return ret;
428 }
429 
430 static int usb_scan_port(struct usb_device_scan *usb_scan)
431 {
432 	ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
433 	unsigned short portstatus;
434 	unsigned short portchange;
435 	struct usb_device *dev;
436 	struct usb_hub_device *hub;
437 	int ret = 0;
438 	int i;
439 
440 	dev = usb_scan->dev;
441 	hub = usb_scan->hub;
442 	i = usb_scan->port;
443 
444 	/*
445 	 * Don't talk to the device before the query delay is expired.
446 	 * This is needed for voltages to stabalize.
447 	 */
448 	if (get_timer(0) < hub->query_delay)
449 		return 0;
450 
451 	ret = usb_get_port_status(dev, i + 1, portsts);
452 	if (ret < 0) {
453 		debug("get_port_status failed\n");
454 		if (get_timer(0) >= hub->connect_timeout) {
455 			debug("devnum=%d port=%d: timeout\n",
456 			      dev->devnum, i + 1);
457 			/* Remove this device from scanning list */
458 			list_del(&usb_scan->list);
459 			free(usb_scan);
460 			return 0;
461 		}
462 		return 0;
463 	}
464 
465 	portstatus = le16_to_cpu(portsts->wPortStatus);
466 	portchange = le16_to_cpu(portsts->wPortChange);
467 	debug("Port %d Status %X Change %X\n", i + 1, portstatus, portchange);
468 
469 	/*
470 	 * No connection change happened, wait a bit more.
471 	 *
472 	 * For some situation, the hub reports no connection change but a
473 	 * device is connected to the port (eg: CCS bit is set but CSC is not
474 	 * in the PORTSC register of a root hub), ignore such case.
475 	 */
476 	if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
477 	    !(portstatus & USB_PORT_STAT_CONNECTION)) {
478 		if (get_timer(0) >= hub->connect_timeout) {
479 			debug("devnum=%d port=%d: timeout\n",
480 			      dev->devnum, i + 1);
481 			/* Remove this device from scanning list */
482 			list_del(&usb_scan->list);
483 			free(usb_scan);
484 			return 0;
485 		}
486 		return 0;
487 	}
488 
489 	if (portchange & USB_PORT_STAT_C_RESET) {
490 		debug("port %d reset change\n", i + 1);
491 		usb_clear_port_feature(dev, i + 1, USB_PORT_FEAT_C_RESET);
492 	}
493 
494 	if ((portchange & USB_SS_PORT_STAT_C_BH_RESET) &&
495 	    usb_hub_is_superspeed(dev)) {
496 		debug("port %d BH reset change\n", i + 1);
497 		usb_clear_port_feature(dev, i + 1, USB_SS_PORT_FEAT_C_BH_RESET);
498 	}
499 
500 	/* A new USB device is ready at this point */
501 	debug("devnum=%d port=%d: USB dev found\n", dev->devnum, i + 1);
502 
503 	usb_hub_port_connect_change(dev, i);
504 
505 	if (portchange & USB_PORT_STAT_C_ENABLE) {
506 		debug("port %d enable change, status %x\n", i + 1, portstatus);
507 		usb_clear_port_feature(dev, i + 1, USB_PORT_FEAT_C_ENABLE);
508 		/*
509 		 * The following hack causes a ghost device problem
510 		 * to Faraday EHCI
511 		 */
512 #ifndef CONFIG_USB_EHCI_FARADAY
513 		/*
514 		 * EM interference sometimes causes bad shielded USB
515 		 * devices to be shutdown by the hub, this hack enables
516 		 * them again. Works at least with mouse driver
517 		 */
518 		if (!(portstatus & USB_PORT_STAT_ENABLE) &&
519 		    (portstatus & USB_PORT_STAT_CONNECTION) &&
520 		    usb_device_has_child_on_port(dev, i)) {
521 			debug("already running port %i disabled by hub (EMI?), re-enabling...\n",
522 			      i + 1);
523 			usb_hub_port_connect_change(dev, i);
524 		}
525 #endif
526 	}
527 
528 	if (portstatus & USB_PORT_STAT_SUSPEND) {
529 		debug("port %d suspend change\n", i + 1);
530 		usb_clear_port_feature(dev, i + 1, USB_PORT_FEAT_SUSPEND);
531 	}
532 
533 	if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
534 		debug("port %d over-current change\n", i + 1);
535 		usb_clear_port_feature(dev, i + 1,
536 				       USB_PORT_FEAT_C_OVER_CURRENT);
537 		/* Only power-on this one port */
538 		usb_set_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
539 		hub->overcurrent_count[i]++;
540 
541 		/*
542 		 * If the max-scan-count is not reached, return without removing
543 		 * the device from scan-list. This will re-issue a new scan.
544 		 */
545 		if (hub->overcurrent_count[i] <=
546 		    PORT_OVERCURRENT_MAX_SCAN_COUNT)
547 			return 0;
548 
549 		/* Otherwise the device will get removed */
550 		printf("Port %d over-current occurred %d times\n", i + 1,
551 		       hub->overcurrent_count[i]);
552 	}
553 
554 	/*
555 	 * We're done with this device, so let's remove this device from
556 	 * scanning list
557 	 */
558 	list_del(&usb_scan->list);
559 	free(usb_scan);
560 
561 	return 0;
562 }
563 
564 static int usb_device_list_scan(void)
565 {
566 	struct usb_device_scan *usb_scan;
567 	struct usb_device_scan *tmp;
568 	static int running;
569 	int ret = 0;
570 
571 	/* Only run this loop once for each controller */
572 	if (running)
573 		return 0;
574 
575 	running = 1;
576 
577 	while (1) {
578 		/* We're done, once the list is empty again */
579 		if (list_empty(&usb_scan_list))
580 			goto out;
581 
582 		list_for_each_entry_safe(usb_scan, tmp, &usb_scan_list, list) {
583 			int ret;
584 
585 			/* Scan this port */
586 			ret = usb_scan_port(usb_scan);
587 			if (ret)
588 				goto out;
589 		}
590 	}
591 
592 out:
593 	/*
594 	 * This USB controller has finished scanning all its connected
595 	 * USB devices. Set "running" back to 0, so that other USB controllers
596 	 * will scan their devices too.
597 	 */
598 	running = 0;
599 
600 	return ret;
601 }
602 
603 static struct usb_hub_device *usb_get_hub_device(struct usb_device *dev)
604 {
605 	struct usb_hub_device *hub;
606 
607 #ifndef CONFIG_DM_USB
608 	/* "allocate" Hub device */
609 	hub = usb_hub_allocate();
610 #else
611 	hub = dev_get_uclass_priv(dev->dev);
612 #endif
613 
614 	return hub;
615 }
616 
617 static int usb_hub_configure(struct usb_device *dev)
618 {
619 	int i, length;
620 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, USB_BUFSIZ);
621 	unsigned char *bitmap;
622 	short hubCharacteristics;
623 	struct usb_hub_descriptor *descriptor;
624 	struct usb_hub_device *hub;
625 	struct usb_hub_status *hubsts;
626 	int ret;
627 
628 	hub = usb_get_hub_device(dev);
629 	if (hub == NULL)
630 		return -ENOMEM;
631 	hub->pusb_dev = dev;
632 
633 	/* Get the the hub descriptor */
634 	ret = usb_get_hub_descriptor(dev, buffer, 4);
635 	if (ret < 0) {
636 		debug("usb_hub_configure: failed to get hub " \
637 		      "descriptor, giving up %lX\n", dev->status);
638 		return ret;
639 	}
640 	descriptor = (struct usb_hub_descriptor *)buffer;
641 
642 	length = min_t(int, descriptor->bLength,
643 		       sizeof(struct usb_hub_descriptor));
644 
645 	ret = usb_get_hub_descriptor(dev, buffer, length);
646 	if (ret < 0) {
647 		debug("usb_hub_configure: failed to get hub " \
648 		      "descriptor 2nd giving up %lX\n", dev->status);
649 		return ret;
650 	}
651 	memcpy((unsigned char *)&hub->desc, buffer, length);
652 	/* adjust 16bit values */
653 	put_unaligned(le16_to_cpu(get_unaligned(
654 			&descriptor->wHubCharacteristics)),
655 			&hub->desc.wHubCharacteristics);
656 	/* set the bitmap */
657 	bitmap = (unsigned char *)&hub->desc.u.hs.DeviceRemovable[0];
658 	/* devices not removable by default */
659 	memset(bitmap, 0xff, (USB_MAXCHILDREN+1+7)/8);
660 	bitmap = (unsigned char *)&hub->desc.u.hs.PortPowerCtrlMask[0];
661 	memset(bitmap, 0xff, (USB_MAXCHILDREN+1+7)/8); /* PowerMask = 1B */
662 
663 	for (i = 0; i < ((hub->desc.bNbrPorts + 1 + 7)/8); i++)
664 		hub->desc.u.hs.DeviceRemovable[i] =
665 			descriptor->u.hs.DeviceRemovable[i];
666 
667 	for (i = 0; i < ((hub->desc.bNbrPorts + 1 + 7)/8); i++)
668 		hub->desc.u.hs.PortPowerCtrlMask[i] =
669 			descriptor->u.hs.PortPowerCtrlMask[i];
670 
671 	dev->maxchild = descriptor->bNbrPorts;
672 	debug("%d ports detected\n", dev->maxchild);
673 
674 	hubCharacteristics = get_unaligned(&hub->desc.wHubCharacteristics);
675 	switch (hubCharacteristics & HUB_CHAR_LPSM) {
676 	case 0x00:
677 		debug("ganged power switching\n");
678 		break;
679 	case 0x01:
680 		debug("individual port power switching\n");
681 		break;
682 	case 0x02:
683 	case 0x03:
684 		debug("unknown reserved power switching mode\n");
685 		break;
686 	}
687 
688 	if (hubCharacteristics & HUB_CHAR_COMPOUND)
689 		debug("part of a compound device\n");
690 	else
691 		debug("standalone hub\n");
692 
693 	switch (hubCharacteristics & HUB_CHAR_OCPM) {
694 	case 0x00:
695 		debug("global over-current protection\n");
696 		break;
697 	case 0x08:
698 		debug("individual port over-current protection\n");
699 		break;
700 	case 0x10:
701 	case 0x18:
702 		debug("no over-current protection\n");
703 		break;
704 	}
705 
706 	switch (dev->descriptor.bDeviceProtocol) {
707 	case USB_HUB_PR_FS:
708 		break;
709 	case USB_HUB_PR_HS_SINGLE_TT:
710 		debug("Single TT\n");
711 		break;
712 	case USB_HUB_PR_HS_MULTI_TT:
713 		ret = usb_set_interface(dev, 0, 1);
714 		if (ret == 0) {
715 			debug("TT per port\n");
716 			hub->tt.multi = true;
717 		} else {
718 			debug("Using single TT (err %d)\n", ret);
719 		}
720 		break;
721 	case USB_HUB_PR_SS:
722 		/* USB 3.0 hubs don't have a TT */
723 		break;
724 	default:
725 		debug("Unrecognized hub protocol %d\n",
726 		      dev->descriptor.bDeviceProtocol);
727 		break;
728 	}
729 
730 	/* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
731 	switch (hubCharacteristics & HUB_CHAR_TTTT) {
732 	case HUB_TTTT_8_BITS:
733 		if (dev->descriptor.bDeviceProtocol != 0) {
734 			hub->tt.think_time = 666;
735 			debug("TT requires at most %d FS bit times (%d ns)\n",
736 			      8, hub->tt.think_time);
737 		}
738 		break;
739 	case HUB_TTTT_16_BITS:
740 		hub->tt.think_time = 666 * 2;
741 		debug("TT requires at most %d FS bit times (%d ns)\n",
742 		      16, hub->tt.think_time);
743 		break;
744 	case HUB_TTTT_24_BITS:
745 		hub->tt.think_time = 666 * 3;
746 		debug("TT requires at most %d FS bit times (%d ns)\n",
747 		      24, hub->tt.think_time);
748 		break;
749 	case HUB_TTTT_32_BITS:
750 		hub->tt.think_time = 666 * 4;
751 		debug("TT requires at most %d FS bit times (%d ns)\n",
752 		      32, hub->tt.think_time);
753 		break;
754 	}
755 
756 	debug("power on to power good time: %dms\n",
757 	      descriptor->bPwrOn2PwrGood * 2);
758 	debug("hub controller current requirement: %dmA\n",
759 	      descriptor->bHubContrCurrent);
760 
761 	for (i = 0; i < dev->maxchild; i++)
762 		debug("port %d is%s removable\n", i + 1,
763 		      hub->desc.u.hs.DeviceRemovable[(i + 1) / 8] & \
764 		      (1 << ((i + 1) % 8)) ? " not" : "");
765 
766 	if (sizeof(struct usb_hub_status) > USB_BUFSIZ) {
767 		debug("usb_hub_configure: failed to get Status - " \
768 		      "too long: %d\n", descriptor->bLength);
769 		return -EFBIG;
770 	}
771 
772 	ret = usb_get_hub_status(dev, buffer);
773 	if (ret < 0) {
774 		debug("usb_hub_configure: failed to get Status %lX\n",
775 		      dev->status);
776 		return ret;
777 	}
778 
779 	hubsts = (struct usb_hub_status *)buffer;
780 
781 	debug("get_hub_status returned status %X, change %X\n",
782 	      le16_to_cpu(hubsts->wHubStatus),
783 	      le16_to_cpu(hubsts->wHubChange));
784 	debug("local power source is %s\n",
785 	      (le16_to_cpu(hubsts->wHubStatus) & HUB_STATUS_LOCAL_POWER) ? \
786 	      "lost (inactive)" : "good");
787 	debug("%sover-current condition exists\n",
788 	      (le16_to_cpu(hubsts->wHubStatus) & HUB_STATUS_OVERCURRENT) ? \
789 	      "" : "no ");
790 
791 #ifdef CONFIG_DM_USB
792 	/*
793 	 * Update USB host controller's internal representation of this hub
794 	 * after the hub descriptor is fetched.
795 	 */
796 	ret = usb_update_hub_device(dev);
797 	if (ret < 0 && ret != -ENOSYS) {
798 		debug("%s: failed to update hub device for HCD (%x)\n",
799 		      __func__, ret);
800 		return ret;
801 	}
802 
803 	/*
804 	 * A maximum of seven tiers are allowed in a USB topology, and the
805 	 * root hub occupies the first tier. The last tier ends with a normal
806 	 * USB device. USB 3.0 hubs use a 20-bit field called 'route string'
807 	 * to route packets to the designated downstream port. The hub uses a
808 	 * hub depth value multiplied by four as an offset into the 'route
809 	 * string' to locate the bits it uses to determine the downstream
810 	 * port number.
811 	 */
812 	if (usb_hub_is_root_hub(dev->dev)) {
813 		hub->hub_depth = -1;
814 	} else {
815 		struct udevice *hdev;
816 		int depth = 0;
817 
818 		hdev = dev->dev->parent;
819 		while (!usb_hub_is_root_hub(hdev)) {
820 			depth++;
821 			hdev = hdev->parent;
822 		}
823 
824 		hub->hub_depth = depth;
825 
826 		if (usb_hub_is_superspeed(dev)) {
827 			debug("set hub (%p) depth to %d\n", dev, depth);
828 			/*
829 			 * This request sets the value that the hub uses to
830 			 * determine the index into the 'route string index'
831 			 * for this hub.
832 			 */
833 			ret = usb_set_hub_depth(dev, depth);
834 			if (ret < 0) {
835 				debug("%s: failed to set hub depth (%lX)\n",
836 				      __func__, dev->status);
837 				return ret;
838 			}
839 		}
840 	}
841 #endif
842 
843 	usb_hub_power_on(hub);
844 
845 	/*
846 	 * Reset any devices that may be in a bad state when applying
847 	 * the power.  This is a __weak function.  Resetting of the devices
848 	 * should occur in the board file of the device.
849 	 */
850 	for (i = 0; i < dev->maxchild; i++)
851 		usb_hub_reset_devices(hub, i + 1);
852 
853 	/*
854 	 * Only add the connected USB devices, including potential hubs,
855 	 * to a scanning list. This list will get scanned and devices that
856 	 * are detected (either via port connected or via port timeout)
857 	 * will get removed from this list. Scanning of the devices on this
858 	 * list will continue until all devices are removed.
859 	 */
860 	for (i = 0; i < dev->maxchild; i++) {
861 		struct usb_device_scan *usb_scan;
862 
863 		usb_scan = calloc(1, sizeof(*usb_scan));
864 		if (!usb_scan) {
865 			printf("Can't allocate memory for USB device!\n");
866 			return -ENOMEM;
867 		}
868 		usb_scan->dev = dev;
869 		usb_scan->hub = hub;
870 		usb_scan->port = i;
871 		list_add_tail(&usb_scan->list, &usb_scan_list);
872 	}
873 
874 	/*
875 	 * And now call the scanning code which loops over the generated list
876 	 */
877 	ret = usb_device_list_scan();
878 
879 	return ret;
880 }
881 
882 static int usb_hub_check(struct usb_device *dev, int ifnum)
883 {
884 	struct usb_interface *iface;
885 	struct usb_endpoint_descriptor *ep = NULL;
886 
887 	iface = &dev->config.if_desc[ifnum];
888 	/* Is it a hub? */
889 	if (iface->desc.bInterfaceClass != USB_CLASS_HUB)
890 		goto err;
891 	/* Some hubs have a subclass of 1, which AFAICT according to the */
892 	/*  specs is not defined, but it works */
893 	if ((iface->desc.bInterfaceSubClass != 0) &&
894 	    (iface->desc.bInterfaceSubClass != 1))
895 		goto err;
896 	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
897 	if (iface->desc.bNumEndpoints != 1)
898 		goto err;
899 	ep = &iface->ep_desc[0];
900 	/* Output endpoint? Curiousier and curiousier.. */
901 	if (!(ep->bEndpointAddress & USB_DIR_IN))
902 		goto err;
903 	/* If it's not an interrupt endpoint, we'd better punt! */
904 	if ((ep->bmAttributes & 3) != 3)
905 		goto err;
906 	/* We found a hub */
907 	debug("USB hub found\n");
908 	return 0;
909 
910 err:
911 	debug("USB hub not found: bInterfaceClass=%d, bInterfaceSubClass=%d, bNumEndpoints=%d\n",
912 	      iface->desc.bInterfaceClass, iface->desc.bInterfaceSubClass,
913 	      iface->desc.bNumEndpoints);
914 	if (ep) {
915 		debug("   bEndpointAddress=%#x, bmAttributes=%d",
916 		      ep->bEndpointAddress, ep->bmAttributes);
917 	}
918 
919 	return -ENOENT;
920 }
921 
922 int usb_hub_probe(struct usb_device *dev, int ifnum)
923 {
924 	int ret;
925 
926 	ret = usb_hub_check(dev, ifnum);
927 	if (ret)
928 		return 0;
929 	ret = usb_hub_configure(dev);
930 	return ret;
931 }
932 
933 #ifdef CONFIG_DM_USB
934 int usb_hub_scan(struct udevice *hub)
935 {
936 	struct usb_device *udev = dev_get_parent_priv(hub);
937 
938 	return usb_hub_configure(udev);
939 }
940 
941 static int usb_hub_post_probe(struct udevice *dev)
942 {
943 	debug("%s\n", __func__);
944 	return usb_hub_scan(dev);
945 }
946 
947 static const struct udevice_id usb_hub_ids[] = {
948 	{ .compatible = "usb-hub" },
949 	{ }
950 };
951 
952 U_BOOT_DRIVER(usb_generic_hub) = {
953 	.name	= "usb_hub",
954 	.id	= UCLASS_USB_HUB,
955 	.of_match = usb_hub_ids,
956 	.flags	= DM_FLAG_ALLOC_PRIV_DMA,
957 };
958 
959 UCLASS_DRIVER(usb_hub) = {
960 	.id		= UCLASS_USB_HUB,
961 	.name		= "usb_hub",
962 	.post_bind	= dm_scan_fdt_dev,
963 	.post_probe	= usb_hub_post_probe,
964 	.child_pre_probe	= usb_child_pre_probe,
965 	.per_child_auto_alloc_size = sizeof(struct usb_device),
966 	.per_child_platdata_auto_alloc_size = sizeof(struct usb_dev_platdata),
967 	.per_device_auto_alloc_size = sizeof(struct usb_hub_device),
968 };
969 
970 static const struct usb_device_id hub_id_table[] = {
971 	{
972 		.match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
973 		.bDeviceClass = USB_CLASS_HUB
974 	},
975 	{ }	/* Terminating entry */
976 };
977 
978 U_BOOT_USB_DEVICE(usb_generic_hub, hub_id_table);
979 
980 #endif
981