xref: /openbsd/sys/dev/usb/uhub.c (revision 3bef86f7)
1 /*	$OpenBSD: uhub.c,v 1.97 2022/09/04 08:42:39 mglocker Exp $ */
2 /*	$NetBSD: uhub.c,v 1.64 2003/02/08 03:32:51 ichiro Exp $	*/
3 /*	$FreeBSD: src/sys/dev/usb/uhub.c,v 1.18 1999/11/17 22:33:43 n_hibma Exp $	*/
4 
5 /*
6  * Copyright (c) 1998 The NetBSD Foundation, Inc.
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to The NetBSD Foundation
10  * by Lennart Augustsson (lennart@augustsson.net) at
11  * Carlstedt Research & Technology.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
24  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
25  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
26  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32  * POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/malloc.h>
39 #include <sys/device.h>
40 
41 #include <machine/bus.h>
42 
43 #include <dev/usb/usb.h>
44 #include <dev/usb/usbdi.h>
45 #include <dev/usb/usbdi_util.h>
46 #include <dev/usb/usbdivar.h>
47 
48 #define UHUB_INTR_INTERVAL 255	/* ms */
49 
50 #ifdef UHUB_DEBUG
51 #define DPRINTF(x...)	do { printf(x); } while (0)
52 #else
53 #define DPRINTF(x...)
54 #endif
55 
56 #define DEVNAME(sc)	((sc)->sc_dev.dv_xname)
57 
58 struct uhub_softc {
59 	struct device		sc_dev;		/* base device */
60 	struct usbd_device	*sc_hub;	/* USB device */
61 	struct usbd_pipe	*sc_ipipe;	/* interrupt pipe */
62 
63 	uint32_t		 sc_status;	/* status from last interrupt */
64 	uint8_t			*sc_statusbuf;	/* per port status buffer */
65 	size_t			 sc_statuslen;	/* status bufferlen */
66 
67 	u_char			sc_running;
68 };
69 #define UHUB_PROTO(sc) ((sc)->sc_hub->ddesc.bDeviceProtocol)
70 #define UHUB_IS_HIGH_SPEED(sc) (UHUB_PROTO(sc) != UDPROTO_FSHUB)
71 #define UHUB_IS_SINGLE_TT(sc) (UHUB_PROTO(sc) == UDPROTO_HSHUBSTT)
72 
73 int uhub_explore(struct usbd_device *hub);
74 void uhub_intr(struct usbd_xfer *, void *, usbd_status);
75 int uhub_port_connect(struct uhub_softc *, int, int);
76 
77 /*
78  * We need two attachment points:
79  * hub to usb and hub to hub
80  * Every other driver only connects to hubs
81  */
82 
83 int uhub_match(struct device *, void *, void *);
84 void uhub_attach(struct device *, struct device *, void *);
85 int uhub_detach(struct device *, int);
86 
87 struct cfdriver uhub_cd = {
88 	NULL, "uhub", DV_DULL
89 };
90 
91 const struct cfattach uhub_ca = {
92 	sizeof(struct uhub_softc), uhub_match, uhub_attach,  uhub_detach
93 };
94 
95 const struct cfattach uhub_uhub_ca = {
96 	sizeof(struct uhub_softc), uhub_match, uhub_attach,  uhub_detach
97 };
98 
99 int
100 uhub_match(struct device *parent, void *match, void *aux)
101 {
102 	struct usb_attach_arg *uaa = aux;
103 	usb_device_descriptor_t *dd = usbd_get_device_descriptor(uaa->device);
104 
105 	if (uaa->iface == NULL)
106 		return (UMATCH_NONE);
107 
108 	/*
109 	 * The subclass for hubs seems to be 0 for some and 1 for others,
110 	 * so we just ignore the subclass.
111 	 */
112 	if (dd->bDeviceClass == UDCLASS_HUB)
113 		return (UMATCH_DEVCLASS_DEVSUBCLASS);
114 	return (UMATCH_NONE);
115 }
116 
117 void
118 uhub_attach(struct device *parent, struct device *self, void *aux)
119 {
120 	struct uhub_softc *sc = (struct uhub_softc *)self;
121 	struct usb_attach_arg *uaa = aux;
122 	struct usbd_device *dev = uaa->device;
123 	struct usbd_hub *hub = NULL;
124 	union {
125 		usb_hub_descriptor_t	hs;
126 		usb_hub_ss_descriptor_t	ss;
127 	} hd;
128 	int p, port, nports, powerdelay;
129 	struct usbd_interface *iface = uaa->iface;
130 	usb_endpoint_descriptor_t *ed;
131 	struct usbd_tt *tts = NULL;
132 	uint8_t ttthink = 0;
133 	usbd_status err;
134 #ifdef UHUB_DEBUG
135 	int nremov;
136 #endif
137 
138 	sc->sc_hub = dev;
139 
140 	if (dev->depth > USB_HUB_MAX_DEPTH) {
141 		printf("%s: hub depth (%d) exceeded, hub ignored\n",
142 		       sc->sc_dev.dv_xname, USB_HUB_MAX_DEPTH);
143 		return;
144 	}
145 
146 	/*
147 	 * Super-Speed hubs need to know their depth to be able to
148 	 * parse the bits of the route-string that correspond to
149 	 * their downstream port number.
150 	 *
151 	 * This does no apply to root hubs.
152 	 */
153 	if (dev->depth != 0 && dev->speed == USB_SPEED_SUPER) {
154 		if (usbd_set_hub_depth(dev, dev->depth - 1)) {
155 			printf("%s: unable to set HUB depth\n",
156 			    sc->sc_dev.dv_xname);
157 			return;
158 		}
159 	}
160 
161 	/* Get hub descriptor. */
162 	if (dev->speed == USB_SPEED_SUPER) {
163 		err = usbd_get_hub_ss_descriptor(dev, &hd.ss, 1);
164 		nports = hd.ss.bNbrPorts;
165 		powerdelay = (hd.ss.bPwrOn2PwrGood * UHD_PWRON_FACTOR);
166 		if (!err && nports > 7)
167 			usbd_get_hub_ss_descriptor(dev, &hd.ss, nports);
168 	} else {
169 		err = usbd_get_hub_descriptor(dev, &hd.hs, 1);
170 		nports = hd.hs.bNbrPorts;
171 		powerdelay = (hd.hs.bPwrOn2PwrGood * UHD_PWRON_FACTOR);
172 		ttthink = UGETW(hd.hs.wHubCharacteristics) & UHD_TT_THINK;
173 		if (!err && nports > 7)
174 			usbd_get_hub_descriptor(dev, &hd.hs, nports);
175 	}
176 
177 	if (err) {
178 		DPRINTF("%s: getting hub descriptor failed, error=%s\n",
179 			 sc->sc_dev.dv_xname, usbd_errstr(err));
180 		return;
181 	}
182 
183 #ifdef UHUB_DEBUG
184 	for (nremov = 0, port = 1; port <= nports; port++) {
185 		if (dev->speed == USB_SPEED_SUPER) {
186 			if (!UHD_NOT_REMOV(&hd.ss, port))
187 				nremov++;
188 		} else {
189 			if (!UHD_NOT_REMOV(&hd.hs, port))
190 				nremov++;
191 		}
192 	}
193 
194 	printf("%s: %d port%s with %d removable, %s powered",
195 	       sc->sc_dev.dv_xname, nports, nports != 1 ? "s" : "",
196 	       nremov, dev->self_powered ? "self" : "bus");
197 
198 	if (dev->depth > 0 && UHUB_IS_HIGH_SPEED(sc)) {
199 		printf(", %s transaction translator%s",
200 		    UHUB_IS_SINGLE_TT(sc) ? "single" : "multiple",
201 		    UHUB_IS_SINGLE_TT(sc) ? "" : "s");
202 	}
203 
204 	printf("\n");
205 #endif
206 
207 	if (nports == 0) {
208 		printf("%s: no ports, hub ignored\n", sc->sc_dev.dv_xname);
209 		goto bad;
210 	}
211 
212 	hub = malloc(sizeof(*hub), M_USBDEV, M_NOWAIT);
213 	if (hub == NULL)
214 		return;
215 	hub->ports = mallocarray(nports, sizeof(struct usbd_port),
216 	    M_USBDEV, M_NOWAIT);
217 	if (hub->ports == NULL) {
218 		free(hub, M_USBDEV, sizeof *hub);
219 		return;
220 	}
221 	dev->hub = hub;
222 	dev->hub->hubsoftc = sc;
223 	hub->explore = uhub_explore;
224 	hub->nports = nports;
225 	hub->powerdelay = powerdelay;
226 	hub->ttthink = ttthink >> 5;
227 	hub->multi = UHUB_IS_SINGLE_TT(sc) ? 0 : 1;
228 
229 	if (!dev->self_powered && dev->powersrc->parent != NULL &&
230 	    !dev->powersrc->parent->self_powered) {
231 		printf("%s: bus powered hub connected to bus powered hub, "
232 		       "ignored\n", sc->sc_dev.dv_xname);
233 		goto bad;
234 	}
235 
236 	/* Set up interrupt pipe. */
237 	ed = usbd_interface2endpoint_descriptor(iface, 0);
238 	if (ed == NULL) {
239 		printf("%s: no endpoint descriptor\n", sc->sc_dev.dv_xname);
240 		goto bad;
241 	}
242 	if (UE_GET_XFERTYPE(ed->bmAttributes) != UE_INTERRUPT) {
243 		printf("%s: bad interrupt endpoint\n", sc->sc_dev.dv_xname);
244 		goto bad;
245 	}
246 
247 	sc->sc_statuslen = (nports + 1 + 7) / 8;
248 	sc->sc_statusbuf = malloc(sc->sc_statuslen, M_USBDEV, M_NOWAIT);
249 	if (!sc->sc_statusbuf)
250 		goto bad;
251 
252 	err = usbd_open_pipe_intr(iface, ed->bEndpointAddress,
253 		  USBD_SHORT_XFER_OK, &sc->sc_ipipe, sc, sc->sc_statusbuf,
254 		  sc->sc_statuslen, uhub_intr, UHUB_INTR_INTERVAL);
255 	if (err) {
256 		printf("%s: cannot open interrupt pipe\n",
257 		       sc->sc_dev.dv_xname);
258 		goto bad;
259 	}
260 
261 	/* Wait with power off for a while. */
262 	usbd_delay_ms(dev, USB_POWER_DOWN_TIME);
263 
264 	/*
265 	 * To have the best chance of success we do things in the exact same
266 	 * order as Windoze98.  This should not be necessary, but some
267 	 * devices do not follow the USB specs to the letter.
268 	 *
269 	 * These are the events on the bus when a hub is attached:
270 	 *  Get device and config descriptors (see attach code)
271 	 *  Get hub descriptor (see above)
272 	 *  For all ports
273 	 *     turn on power
274 	 *     wait for power to become stable
275 	 * (all below happens in explore code)
276 	 *  For all ports
277 	 *     clear C_PORT_CONNECTION
278 	 *  For all ports
279 	 *     get port status
280 	 *     if device connected
281 	 *        wait 100 ms
282 	 *        turn on reset
283 	 *        wait
284 	 *        clear C_PORT_RESET
285 	 *        get port status
286 	 *        proceed with device attachment
287 	 */
288 
289 	if (UHUB_IS_HIGH_SPEED(sc)) {
290 		tts = mallocarray((UHUB_IS_SINGLE_TT(sc) ? 1 : nports),
291 		    sizeof(struct usbd_tt), M_USBDEV, M_NOWAIT);
292 		if (!tts)
293 			goto bad;
294 	}
295 	/* Set up data structures */
296 	for (p = 0; p < nports; p++) {
297 		struct usbd_port *up = &hub->ports[p];
298 		up->device = NULL;
299 		up->parent = dev;
300 		up->portno = p + 1;
301 		if (dev->self_powered)
302 			/* Self powered hub, give ports maximum current. */
303 			up->power = USB_MAX_POWER;
304 		else
305 			up->power = USB_MIN_POWER;
306 		up->restartcnt = 0;
307 		up->reattach = 0;
308 		if (UHUB_IS_HIGH_SPEED(sc)) {
309 			up->tt = &tts[UHUB_IS_SINGLE_TT(sc) ? 0 : p];
310 			up->tt->hub = hub;
311 			up->tt->hcpriv = NULL;
312 		} else {
313 			up->tt = NULL;
314 		}
315 	}
316 
317 	for (port = 1; port <= nports; port++) {
318 		/* Turn the power on. */
319 		err = usbd_set_port_feature(dev, port, UHF_PORT_POWER);
320 		if (err)
321 			printf("%s: port %d power on failed, %s\n",
322 			       sc->sc_dev.dv_xname, port,
323 			       usbd_errstr(err));
324 		/* Make sure we check the port status at least once. */
325 		sc->sc_status |= (1 << port);
326 	}
327 
328 	/* Wait for stable power. */
329         if (dev->powersrc->parent != NULL)
330 		usbd_delay_ms(dev, powerdelay + USB_EXTRA_POWER_UP_TIME);
331 
332 	/* The usual exploration will finish the setup. */
333 
334 	sc->sc_running = 1;
335 
336 	return;
337 
338  bad:
339 	free(sc->sc_statusbuf, M_USBDEV, sc->sc_statuslen);
340 	if (hub) {
341 		free(hub->ports, M_USBDEV, hub->nports * sizeof(*hub->ports));
342 		free(hub, M_USBDEV, sizeof(*hub));
343 	}
344 	dev->hub = NULL;
345 }
346 
347 int
348 uhub_explore(struct usbd_device *dev)
349 {
350 	struct uhub_softc *sc = dev->hub->hubsoftc;
351 	struct usbd_port *up;
352 	int status, change;
353 	int port;
354 
355 	if (usbd_is_dying(sc->sc_hub))
356 		return (EIO);
357 
358 	if (!sc->sc_running)
359 		return (ENXIO);
360 
361 	/* Ignore hubs that are too deep. */
362 	if (sc->sc_hub->depth > USB_HUB_MAX_DEPTH)
363 		return (EOPNOTSUPP);
364 
365 	for (port = 1; port <= sc->sc_hub->hub->nports; port++) {
366 		up = &sc->sc_hub->hub->ports[port-1];
367 
368 		change = 0;
369 		status = 0;
370 
371 		if ((sc->sc_status & (1 << port)) || up->reattach) {
372 			sc->sc_status &= ~(1 << port);
373 
374 			if (usbd_get_port_status(dev, port, &up->status))
375 				continue;
376 
377 			status = UGETW(up->status.wPortStatus);
378 			change = UGETW(up->status.wPortChange);
379 			DPRINTF("%s: port %d status=0x%04x change=0x%04x\n",
380 			    sc->sc_dev.dv_xname, port, status, change);
381 		}
382 
383 		if (up->reattach) {
384 			change |= UPS_C_CONNECT_STATUS;
385 			up->reattach = 0;
386 		}
387 
388 		if (change & UPS_C_PORT_ENABLED) {
389 			usbd_clear_port_feature(sc->sc_hub, port,
390 			    UHF_C_PORT_ENABLE);
391 			if (change & UPS_C_CONNECT_STATUS) {
392 				/* Ignore the port error if the device
393 				   vanished. */
394 			} else if (status & UPS_PORT_ENABLED) {
395 				printf("%s: illegal enable change, port %d\n",
396 				       sc->sc_dev.dv_xname, port);
397 			} else {
398 				/* Port error condition. */
399 				if (up->restartcnt) /* no message first time */
400 					printf("%s: port error, restarting "
401 					       "port %d\n",
402 					       sc->sc_dev.dv_xname, port);
403 
404 				if (up->restartcnt++ < USBD_RESTART_MAX)
405 					change |= UPS_C_CONNECT_STATUS;
406 				else
407 					printf("%s: port error, giving up "
408 					       "port %d\n",
409 					       sc->sc_dev.dv_xname, port);
410 			}
411 		}
412 
413 		if (change & UPS_C_PORT_RESET) {
414 			usbd_clear_port_feature(sc->sc_hub, port,
415 			    UHF_C_PORT_RESET);
416 			change |= UPS_C_CONNECT_STATUS;
417 		}
418 
419 		if (change & UPS_C_BH_PORT_RESET &&
420 		    sc->sc_hub->speed == USB_SPEED_SUPER) {
421 			usbd_clear_port_feature(sc->sc_hub, port,
422 			    UHF_C_BH_PORT_RESET);
423 		}
424 
425 		if (change & UPS_C_CONNECT_STATUS) {
426 			if (uhub_port_connect(sc, port, status))
427 				continue;
428 
429 			/* The port set up succeeded, reset error count. */
430 			up->restartcnt = 0;
431 		}
432 
433 		if (change & UPS_C_PORT_LINK_STATE) {
434 			usbd_clear_port_feature(sc->sc_hub, port,
435 			    UHF_C_PORT_LINK_STATE);
436 		}
437 
438 		/* Recursive explore. */
439 		if (up->device != NULL && up->device->hub != NULL)
440 			up->device->hub->explore(up->device);
441 	}
442 
443 	return (0);
444 }
445 
446 /*
447  * Called from process context when the hub is gone.
448  * Detach all devices on active ports.
449  */
450 int
451 uhub_detach(struct device *self, int flags)
452 {
453 	struct uhub_softc *sc = (struct uhub_softc *)self;
454 	struct usbd_hub *hub = sc->sc_hub->hub;
455 	struct usbd_port *rup;
456 	int port;
457 
458 	if (hub == NULL)		/* Must be partially working */
459 		return (0);
460 
461 	usbd_close_pipe(sc->sc_ipipe);
462 
463 	for (port = 0; port < hub->nports; port++) {
464 		rup = &hub->ports[port];
465 		if (rup->device != NULL) {
466 			usbd_detach(rup->device, self);
467 			rup->device = NULL;
468 		}
469 	}
470 
471 	free(hub->ports[0].tt, M_USBDEV,
472 	    (UHUB_IS_SINGLE_TT(sc) ? 1 : hub->nports) * sizeof(struct usbd_tt));
473 	free(sc->sc_statusbuf, M_USBDEV, sc->sc_statuslen);
474 	free(hub->ports, M_USBDEV, hub->nports * sizeof(*hub->ports));
475 	free(hub, M_USBDEV, sizeof(*hub));
476 	sc->sc_hub->hub = NULL;
477 
478 	return (0);
479 }
480 
481 /*
482  * This is an indication that some port has changed status.  Remember
483  * the ports that need attention and notify the USB task thread that
484  * we need to be explored again.
485  */
486 void
487 uhub_intr(struct usbd_xfer *xfer, void *addr, usbd_status status)
488 {
489 	struct uhub_softc *sc = addr;
490 	uint32_t stats = 0;
491 	int i;
492 
493 	if (usbd_is_dying(sc->sc_hub))
494 		return;
495 
496 	DPRINTF("%s: intr status=%d\n", sc->sc_dev.dv_xname, status);
497 
498 	if (status == USBD_STALLED)
499 		usbd_clear_endpoint_stall_async(sc->sc_ipipe);
500 	else if (status == USBD_NORMAL_COMPLETION) {
501 		for (i = 0; i < xfer->actlen; i++)
502 			stats |= (uint32_t)(xfer->buffer[i]) << (i * 8);
503 		sc->sc_status |= stats;
504 
505 		usb_needs_explore(sc->sc_hub, 0);
506 	}
507 }
508 
509 int
510 uhub_port_connect(struct uhub_softc *sc, int port, int status)
511 {
512 	struct usbd_port *up = &sc->sc_hub->hub->ports[port-1];
513 	int speed, change;
514 
515 	/* We have a connect status change, handle it. */
516 	usbd_clear_port_feature(sc->sc_hub, port, UHF_C_PORT_CONNECTION);
517 
518 	/*
519 	 * If there is already a device on the port the change status
520 	 * must mean that is has disconnected.  Looking at the
521 	 * current connect status is not enough to figure this out
522 	 * since a new unit may have been connected before we handle
523 	 * the disconnect.
524 	 */
525 	if (up->device != NULL) {
526 		/* Disconnected */
527 		usbd_detach(up->device, &sc->sc_dev);
528 		up->device = NULL;
529 	}
530 
531 	/* Nothing connected, just ignore it. */
532 	if ((status & UPS_CURRENT_CONNECT_STATUS) == 0)
533 		return (0);
534 
535 	/* Connected */
536 	if ((status & (UPS_PORT_POWER|UPS_PORT_POWER_SS)) == 0) {
537 		printf("%s: connected port %d has no power\n", DEVNAME(sc),
538 		    port);
539 		return (-1);
540 	}
541 
542 	/* Wait for maximum device power up time. */
543 	usbd_delay_ms(sc->sc_hub, USB_PORT_POWERUP_DELAY);
544 
545 	/* Reset port, which implies enabling it. */
546 	if (usbd_reset_port(sc->sc_hub, port)) {
547 		printf("%s: port %d reset failed\n", DEVNAME(sc), port);
548 		return (-1);
549 	}
550 	/* Get port status again, it might have changed during reset */
551 	if (usbd_get_port_status(sc->sc_hub, port, &up->status))
552 		return (-1);
553 
554 	status = UGETW(up->status.wPortStatus);
555 	change = UGETW(up->status.wPortChange);
556 	DPRINTF("%s: port %d status=0x%04x change=0x%04x\n", DEVNAME(sc),
557 	    port, status, change);
558 
559 	/* Nothing connected, just ignore it. */
560 	if ((status & UPS_CURRENT_CONNECT_STATUS) == 0) {
561 		DPRINTF("%s: port %d, device disappeared after reset\n",
562 		    DEVNAME(sc), port);
563 		return (-1);
564 	}
565 
566 	/*
567 	 * Figure out device speed.  This is a bit tricky because
568 	 * UPS_PORT_POWER_SS and UPS_LOW_SPEED share the same bit.
569 	 */
570 	if ((status & UPS_PORT_POWER) == 0)
571 		status &= ~UPS_PORT_POWER_SS;
572 
573 	if (status & UPS_HIGH_SPEED)
574 		speed = USB_SPEED_HIGH;
575 	else if (status & UPS_LOW_SPEED)
576 		speed = USB_SPEED_LOW;
577 	else {
578 		/*
579 		 * If there is no power bit set, it is certainly
580 		 * a Super Speed device, so use the speed of its
581 		 * parent hub.
582 		 */
583 		if (status & UPS_PORT_POWER)
584 			speed = USB_SPEED_FULL;
585 		else
586 			speed = sc->sc_hub->speed;
587 	}
588 
589 	/*
590 	 * Reduce the speed, otherwise we won't setup the proper
591 	 * transfer methods.
592 	 */
593 	if (speed > sc->sc_hub->speed)
594 		speed = sc->sc_hub->speed;
595 
596 	/* Get device info and set its address. */
597 	if (usbd_new_device(&sc->sc_dev, sc->sc_hub->bus, sc->sc_hub->depth + 1,
598 	    speed, port, up)) {
599 		/*
600 		 * The unit refused to accept a new address, or had
601 		 * some other serious problem.  Since we cannot leave
602 		 * at 0 we have to disable the port instead.
603 		 */
604 		printf("%s: device problem, disabling port %d\n", DEVNAME(sc),
605 		    port);
606 		usbd_clear_port_feature(sc->sc_hub, port, UHF_PORT_ENABLE);
607 
608 		return (-1);
609 	}
610 
611 	return (0);
612 }
613