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usb.c revision 1.91
      1 /*	$NetBSD: usb.c,v 1.91 2006/11/16 01:33:27 christos Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1998, 2002 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Lennart Augustsson (lennart (at) augustsson.net) at
      9  * Carlstedt Research & Technology.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  * 3. All advertising materials mentioning features or use of this software
     20  *    must display the following acknowledgement:
     21  *        This product includes software developed by the NetBSD
     22  *        Foundation, Inc. and its contributors.
     23  * 4. Neither the name of The NetBSD Foundation nor the names of its
     24  *    contributors may be used to endorse or promote products derived
     25  *    from this software without specific prior written permission.
     26  *
     27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     37  * POSSIBILITY OF SUCH DAMAGE.
     38  */
     39 
     40 /*
     41  * USB specifications and other documentation can be found at
     42  * http://www.usb.org/developers/docs/ and
     43  * http://www.usb.org/developers/devclass_docs/
     44  */
     45 
     46 #include <sys/cdefs.h>
     47 __KERNEL_RCSID(0, "$NetBSD: usb.c,v 1.91 2006/11/16 01:33:27 christos Exp $");
     48 
     49 #include "ohci.h"
     50 #include "uhci.h"
     51 
     52 #include <sys/param.h>
     53 #include <sys/systm.h>
     54 #include <sys/kernel.h>
     55 #include <sys/malloc.h>
     56 #include <sys/device.h>
     57 #include <sys/kthread.h>
     58 #include <sys/proc.h>
     59 #include <sys/conf.h>
     60 #include <sys/fcntl.h>
     61 #include <sys/poll.h>
     62 #include <sys/select.h>
     63 #include <sys/vnode.h>
     64 #include <sys/signalvar.h>
     65 
     66 #include <dev/usb/usb.h>
     67 #include <dev/usb/usbdi.h>
     68 #include <dev/usb/usbdi_util.h>
     69 
     70 #define USB_DEV_MINOR 255
     71 
     72 #include <machine/bus.h>
     73 
     74 #include <dev/usb/usbdivar.h>
     75 #include <dev/usb/usb_quirks.h>
     76 
     77 #ifdef USB_DEBUG
     78 #define DPRINTF(x)	if (usbdebug) logprintf x
     79 #define DPRINTFN(n,x)	if (usbdebug>(n)) logprintf x
     80 int	usbdebug = 0;
     81 #if defined(UHCI_DEBUG) && NUHCI > 0
     82 extern int	uhcidebug;
     83 #endif
     84 #if defined(OHCI_DEBUG) && NOHCI > 0
     85 extern int	ohcidebug;
     86 #endif
     87 /*
     88  * 0  - do usual exploration
     89  * 1  - do not use timeout exploration
     90  * >1 - do no exploration
     91  */
     92 int	usb_noexplore = 0;
     93 #else
     94 #define DPRINTF(x)
     95 #define DPRINTFN(n,x)
     96 #endif
     97 
     98 struct usb_softc {
     99 	USBBASEDEVICE	sc_dev;		/* base device */
    100 	usbd_bus_handle sc_bus;		/* USB controller */
    101 	struct usbd_port sc_port;	/* dummy port for root hub */
    102 
    103 	struct proc	*sc_event_thread;
    104 
    105 	char		sc_dying;
    106 };
    107 
    108 struct usb_taskq {
    109 	TAILQ_HEAD(, usb_task) tasks;
    110 	struct proc *task_thread_proc;
    111 	const char *name;
    112 	int taskcreated;	/* task thread exists. */
    113 };
    114 
    115 static struct usb_taskq usb_taskq[USB_NUM_TASKQS];
    116 
    117 dev_type_open(usbopen);
    118 dev_type_close(usbclose);
    119 dev_type_read(usbread);
    120 dev_type_ioctl(usbioctl);
    121 dev_type_poll(usbpoll);
    122 dev_type_kqfilter(usbkqfilter);
    123 
    124 const struct cdevsw usb_cdevsw = {
    125 	usbopen, usbclose, usbread, nowrite, usbioctl,
    126 	nostop, notty, usbpoll, nommap, usbkqfilter, D_OTHER,
    127 };
    128 
    129 Static void	usb_discover(void *);
    130 Static void	usb_create_event_thread(void *);
    131 Static void	usb_event_thread(void *);
    132 Static void	usb_task_thread(void *);
    133 
    134 #define USB_MAX_EVENTS 100
    135 struct usb_event_q {
    136 	struct usb_event ue;
    137 	SIMPLEQ_ENTRY(usb_event_q) next;
    138 };
    139 Static SIMPLEQ_HEAD(, usb_event_q) usb_events =
    140 	SIMPLEQ_HEAD_INITIALIZER(usb_events);
    141 Static int usb_nevents = 0;
    142 Static struct selinfo usb_selevent;
    143 Static usb_proc_ptr usb_async_proc;  /* process that wants USB SIGIO */
    144 Static int usb_dev_open = 0;
    145 Static struct usb_event *usb_alloc_event(void);
    146 Static void usb_free_event(struct usb_event *);
    147 Static void usb_add_event(int, struct usb_event *);
    148 
    149 Static int usb_get_next_event(struct usb_event *);
    150 
    151 Static const char *usbrev_str[] = USBREV_STR;
    152 
    153 USB_DECLARE_DRIVER(usb);
    154 
    155 USB_MATCH(usb)
    156 {
    157 	DPRINTF(("usbd_match\n"));
    158 	return (UMATCH_GENERIC);
    159 }
    160 
    161 USB_ATTACH(usb)
    162 {
    163 	struct usb_softc *sc = (struct usb_softc *)self;
    164 	usbd_device_handle dev;
    165 	usbd_status err;
    166 	int usbrev;
    167 	int speed;
    168 	struct usb_event *ue;
    169 
    170 	DPRINTF(("usbd_attach\n"));
    171 
    172 	usbd_init();
    173 	sc->sc_bus = aux;
    174 	sc->sc_bus->usbctl = sc;
    175 	sc->sc_port.power = USB_MAX_POWER;
    176 
    177 	usbrev = sc->sc_bus->usbrev;
    178 	printf(": USB revision %s", usbrev_str[usbrev]);
    179 	switch (usbrev) {
    180 	case USBREV_1_0:
    181 	case USBREV_1_1:
    182 		speed = USB_SPEED_FULL;
    183 		break;
    184 	case USBREV_2_0:
    185 		speed = USB_SPEED_HIGH;
    186 		break;
    187 	default:
    188 		printf(", not supported\n");
    189 		sc->sc_dying = 1;
    190 		USB_ATTACH_ERROR_RETURN;
    191 	}
    192 	printf("\n");
    193 
    194 	/* Make sure not to use tsleep() if we are cold booting. */
    195 	if (cold)
    196 		sc->sc_bus->use_polling++;
    197 
    198 	ue = usb_alloc_event();
    199 	ue->u.ue_ctrlr.ue_bus = USBDEVUNIT(sc->sc_dev);
    200 	usb_add_event(USB_EVENT_CTRLR_ATTACH, ue);
    201 
    202 #ifdef USB_USE_SOFTINTR
    203 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
    204 	/* XXX we should have our own level */
    205 	sc->sc_bus->soft = softintr_establish(IPL_SOFTNET,
    206 	    sc->sc_bus->methods->soft_intr, sc->sc_bus);
    207 	if (sc->sc_bus->soft == NULL) {
    208 		printf("%s: can't register softintr\n", USBDEVNAME(sc->sc_dev));
    209 		sc->sc_dying = 1;
    210 		USB_ATTACH_ERROR_RETURN;
    211 	}
    212 #else
    213 	usb_callout_init(sc->sc_bus->softi);
    214 #endif
    215 #endif
    216 
    217 	err = usbd_new_device(USBDEV(sc->sc_dev), sc->sc_bus, 0, speed, 0,
    218 		  &sc->sc_port);
    219 	if (!err) {
    220 		dev = sc->sc_port.device;
    221 		if (dev->hub == NULL) {
    222 			sc->sc_dying = 1;
    223 			printf("%s: root device is not a hub\n",
    224 			       USBDEVNAME(sc->sc_dev));
    225 			USB_ATTACH_ERROR_RETURN;
    226 		}
    227 		sc->sc_bus->root_hub = dev;
    228 #if 1
    229 		/*
    230 		 * Turning this code off will delay attachment of USB devices
    231 		 * until the USB event thread is running, which means that
    232 		 * the keyboard will not work until after cold boot.
    233 		 */
    234 		if (cold && (device_cfdata(&sc->sc_dev)->cf_flags & 1))
    235 			dev->hub->explore(sc->sc_bus->root_hub);
    236 #endif
    237 	} else {
    238 		printf("%s: root hub problem, error=%d\n",
    239 		       USBDEVNAME(sc->sc_dev), err);
    240 		sc->sc_dying = 1;
    241 	}
    242 	if (cold)
    243 		sc->sc_bus->use_polling--;
    244 
    245 	config_pending_incr();
    246 	usb_kthread_create(usb_create_event_thread, sc);
    247 
    248 	USB_ATTACH_SUCCESS_RETURN;
    249 }
    250 
    251 static const char *taskq_names[] = USB_TASKQ_NAMES;
    252 
    253 #if defined(__NetBSD__) || defined(__OpenBSD__)
    254 void
    255 usb_create_event_thread(void *arg)
    256 {
    257 	struct usb_softc *sc = arg;
    258 	struct usb_taskq *taskq;
    259 	int i;
    260 
    261 	if (usb_kthread_create1(usb_event_thread, sc, &sc->sc_event_thread,
    262 			   "%s", sc->sc_dev.dv_xname)) {
    263 		printf("%s: unable to create event thread for\n",
    264 		       sc->sc_dev.dv_xname);
    265 		panic("usb_create_event_thread");
    266 	}
    267 	for (i = 0; i < USB_NUM_TASKQS; i++) {
    268 		taskq = &usb_taskq[i];
    269 
    270 		if (taskq->taskcreated)
    271 			continue;
    272 
    273 		TAILQ_INIT(&taskq->tasks);
    274 		taskq->taskcreated = 1;
    275 		taskq->name = taskq_names[i];
    276 		if (usb_kthread_create1(usb_task_thread, taskq,
    277 					&taskq->task_thread_proc, taskq->name)) {
    278 			printf("unable to create task thread: %s\n", taskq->name);
    279 			panic("usb_create_event_thread task");
    280 		}
    281 	}
    282 }
    283 
    284 /*
    285  * Add a task to be performed by the task thread.  This function can be
    286  * called from any context and the task will be executed in a process
    287  * context ASAP.
    288  */
    289 void
    290 usb_add_task(usbd_device_handle dev, struct usb_task *task, int queue)
    291 {
    292 	struct usb_taskq *taskq;
    293 	int s;
    294 
    295 	taskq = &usb_taskq[queue];
    296 	s = splusb();
    297 	if (task->queue == -1) {
    298 		DPRINTFN(2,("usb_add_task: task=%p\n", task));
    299 		TAILQ_INSERT_TAIL(&taskq->tasks, task, next);
    300 		task->queue = queue;
    301 	} else {
    302 		DPRINTFN(3,("usb_add_task: task=%p on q\n", task));
    303 	}
    304 	wakeup(&taskq->tasks);
    305 	splx(s);
    306 }
    307 
    308 void
    309 usb_rem_task(usbd_device_handle dev, struct usb_task *task)
    310 {
    311 	struct usb_taskq *taskq;
    312 	int s;
    313 
    314 	taskq = &usb_taskq[task->queue];
    315 	s = splusb();
    316 	if (task->queue != -1) {
    317 		TAILQ_REMOVE(&taskq->tasks, task, next);
    318 		task->queue = -1;
    319 	}
    320 	splx(s);
    321 }
    322 
    323 void
    324 usb_event_thread(void *arg)
    325 {
    326 	struct usb_softc *sc = arg;
    327 
    328 	DPRINTF(("usb_event_thread: start\n"));
    329 
    330 	/*
    331 	 * In case this controller is a companion controller to an
    332 	 * EHCI controller we need to wait until the EHCI controller
    333 	 * has grabbed the port.
    334 	 * XXX It would be nicer to do this with a tsleep(), but I don't
    335 	 * know how to synchronize the creation of the threads so it
    336 	 * will work.
    337 	 */
    338 	usb_delay_ms(sc->sc_bus, 500);
    339 
    340 	/* Make sure first discover does something. */
    341 	sc->sc_bus->needs_explore = 1;
    342 	usb_discover(sc);
    343 	config_pending_decr();
    344 
    345 	while (!sc->sc_dying) {
    346 #ifdef USB_DEBUG
    347 		if (usb_noexplore < 2)
    348 #endif
    349 		usb_discover(sc);
    350 #ifdef USB_DEBUG
    351 		(void)tsleep(&sc->sc_bus->needs_explore, PWAIT, "usbevt",
    352 		    usb_noexplore ? 0 : hz * 60);
    353 #else
    354 		(void)tsleep(&sc->sc_bus->needs_explore, PWAIT, "usbevt",
    355 		    hz * 60);
    356 #endif
    357 		DPRINTFN(2,("usb_event_thread: woke up\n"));
    358 	}
    359 	sc->sc_event_thread = NULL;
    360 
    361 	/* In case parent is waiting for us to exit. */
    362 	wakeup(sc);
    363 
    364 	DPRINTF(("usb_event_thread: exit\n"));
    365 	kthread_exit(0);
    366 }
    367 
    368 void
    369 usb_task_thread(void *arg)
    370 {
    371 	struct usb_task *task;
    372 	struct usb_taskq *taskq;
    373 	int s;
    374 
    375 	taskq = arg;
    376 	DPRINTF(("usb_task_thread: start taskq %s\n", taskq->name));
    377 
    378 	s = splusb();
    379 	for (;;) {
    380 		task = TAILQ_FIRST(&taskq->tasks);
    381 		if (task == NULL) {
    382 			tsleep(&taskq->tasks, PWAIT, "usbtsk", 0);
    383 			task = TAILQ_FIRST(&taskq->tasks);
    384 		}
    385 		DPRINTFN(2,("usb_task_thread: woke up task=%p\n", task));
    386 		if (task != NULL) {
    387 			TAILQ_REMOVE(&taskq->tasks, task, next);
    388 			task->queue = -1;
    389 			splx(s);
    390 			task->fun(task->arg);
    391 			s = splusb();
    392 		}
    393 	}
    394 }
    395 
    396 int
    397 usbctlprint(void *aux, const char *pnp)
    398 {
    399 	/* only "usb"es can attach to host controllers */
    400 	if (pnp)
    401 		aprint_normal("usb at %s", pnp);
    402 
    403 	return (UNCONF);
    404 }
    405 #endif /* defined(__NetBSD__) || defined(__OpenBSD__) */
    406 
    407 int
    408 usbopen(dev_t dev, int flag, int mode, struct lwp *l)
    409 {
    410 	int unit = minor(dev);
    411 	struct usb_softc *sc;
    412 
    413 	if (unit == USB_DEV_MINOR) {
    414 		if (usb_dev_open)
    415 			return (EBUSY);
    416 		usb_dev_open = 1;
    417 		usb_async_proc = 0;
    418 		return (0);
    419 	}
    420 
    421 	USB_GET_SC_OPEN(usb, unit, sc);
    422 
    423 	if (sc->sc_dying)
    424 		return (EIO);
    425 
    426 	return (0);
    427 }
    428 
    429 int
    430 usbread(dev_t dev, struct uio *uio, int flag)
    431 {
    432 	struct usb_event *ue = usb_alloc_event();
    433 	int s, error, n;
    434 
    435 	if (minor(dev) != USB_DEV_MINOR)
    436 		return (ENXIO);
    437 
    438 	if (uio->uio_resid != sizeof(struct usb_event))
    439 		return (EINVAL);
    440 
    441 	error = 0;
    442 	s = splusb();
    443 	for (;;) {
    444 		n = usb_get_next_event(ue);
    445 		if (n != 0)
    446 			break;
    447 		if (flag & IO_NDELAY) {
    448 			error = EWOULDBLOCK;
    449 			break;
    450 		}
    451 		error = tsleep(&usb_events, PZERO | PCATCH, "usbrea", 0);
    452 		if (error)
    453 			break;
    454 	}
    455 	splx(s);
    456 	if (!error)
    457 		error = uiomove((void *)ue, uio->uio_resid, uio);
    458 	usb_free_event(ue);
    459 
    460 	return (error);
    461 }
    462 
    463 int
    464 usbclose(dev_t dev, int flag, int mode,
    465     struct lwp *l)
    466 {
    467 	int unit = minor(dev);
    468 
    469 	if (unit == USB_DEV_MINOR) {
    470 		usb_async_proc = 0;
    471 		usb_dev_open = 0;
    472 	}
    473 
    474 	return (0);
    475 }
    476 
    477 int
    478 usbioctl(dev_t devt, u_long cmd, caddr_t data, int flag, struct lwp *l)
    479 {
    480 	struct usb_softc *sc;
    481 	int unit = minor(devt);
    482 
    483 	if (unit == USB_DEV_MINOR) {
    484 		switch (cmd) {
    485 		case FIONBIO:
    486 			/* All handled in the upper FS layer. */
    487 			return (0);
    488 
    489 		case FIOASYNC:
    490 			if (*(int *)data)
    491 				usb_async_proc = l->l_proc;
    492 			else
    493 				usb_async_proc = 0;
    494 			return (0);
    495 
    496 		default:
    497 			return (EINVAL);
    498 		}
    499 	}
    500 
    501 	USB_GET_SC(usb, unit, sc);
    502 
    503 	if (sc->sc_dying)
    504 		return (EIO);
    505 
    506 	switch (cmd) {
    507 #ifdef USB_DEBUG
    508 	case USB_SETDEBUG:
    509 		if (!(flag & FWRITE))
    510 			return (EBADF);
    511 		usbdebug  = ((*(int *)data) & 0x000000ff);
    512 #if defined(UHCI_DEBUG) && NUHCI > 0
    513 		uhcidebug = ((*(int *)data) & 0x0000ff00) >> 8;
    514 #endif
    515 #if defined(OHCI_DEBUG) && NOHCI > 0
    516 		ohcidebug = ((*(int *)data) & 0x00ff0000) >> 16;
    517 #endif
    518 		break;
    519 #endif /* USB_DEBUG */
    520 	case USB_REQUEST:
    521 	{
    522 		struct usb_ctl_request *ur = (void *)data;
    523 		int len = UGETW(ur->ucr_request.wLength);
    524 		struct iovec iov;
    525 		struct uio uio;
    526 		void *ptr = 0;
    527 		int addr = ur->ucr_addr;
    528 		usbd_status err;
    529 		int error = 0;
    530 
    531 		if (!(flag & FWRITE))
    532 			return (EBADF);
    533 
    534 		DPRINTF(("usbioctl: USB_REQUEST addr=%d len=%d\n", addr, len));
    535 		if (len < 0 || len > 32768)
    536 			return (EINVAL);
    537 		if (addr < 0 || addr >= USB_MAX_DEVICES ||
    538 		    sc->sc_bus->devices[addr] == 0)
    539 			return (EINVAL);
    540 		if (len != 0) {
    541 			iov.iov_base = (caddr_t)ur->ucr_data;
    542 			iov.iov_len = len;
    543 			uio.uio_iov = &iov;
    544 			uio.uio_iovcnt = 1;
    545 			uio.uio_resid = len;
    546 			uio.uio_offset = 0;
    547 			uio.uio_rw =
    548 				ur->ucr_request.bmRequestType & UT_READ ?
    549 				UIO_READ : UIO_WRITE;
    550 			uio.uio_vmspace = l->l_proc->p_vmspace;
    551 			ptr = malloc(len, M_TEMP, M_WAITOK);
    552 			if (uio.uio_rw == UIO_WRITE) {
    553 				error = uiomove(ptr, len, &uio);
    554 				if (error)
    555 					goto ret;
    556 			}
    557 		}
    558 		err = usbd_do_request_flags(sc->sc_bus->devices[addr],
    559 			  &ur->ucr_request, ptr, ur->ucr_flags, &ur->ucr_actlen,
    560 			  USBD_DEFAULT_TIMEOUT);
    561 		if (err) {
    562 			error = EIO;
    563 			goto ret;
    564 		}
    565 		if (len != 0) {
    566 			if (uio.uio_rw == UIO_READ) {
    567 				error = uiomove(ptr, len, &uio);
    568 				if (error)
    569 					goto ret;
    570 			}
    571 		}
    572 	ret:
    573 		if (ptr)
    574 			free(ptr, M_TEMP);
    575 		return (error);
    576 	}
    577 
    578 	case USB_DEVICEINFO:
    579 	{
    580 		struct usb_device_info *di = (void *)data;
    581 		int addr = di->udi_addr;
    582 		usbd_device_handle dev;
    583 
    584 		if (addr < 1 || addr >= USB_MAX_DEVICES)
    585 			return (EINVAL);
    586 		dev = sc->sc_bus->devices[addr];
    587 		if (dev == NULL)
    588 			return (ENXIO);
    589 		usbd_fill_deviceinfo(dev, di, 1);
    590 		break;
    591 	}
    592 
    593 	case USB_DEVICESTATS:
    594 		*(struct usb_device_stats *)data = sc->sc_bus->stats;
    595 		break;
    596 
    597 	default:
    598 		return (EINVAL);
    599 	}
    600 	return (0);
    601 }
    602 
    603 int
    604 usbpoll(dev_t dev, int events, struct lwp *l)
    605 {
    606 	int revents, mask, s;
    607 
    608 	if (minor(dev) == USB_DEV_MINOR) {
    609 		revents = 0;
    610 		mask = POLLIN | POLLRDNORM;
    611 
    612 		s = splusb();
    613 		if (events & mask && usb_nevents > 0)
    614 			revents |= events & mask;
    615 		if (revents == 0 && events & mask)
    616 			selrecord(l, &usb_selevent);
    617 		splx(s);
    618 
    619 		return (revents);
    620 	} else {
    621 		return (0);
    622 	}
    623 }
    624 
    625 static void
    626 filt_usbrdetach(struct knote *kn)
    627 {
    628 	int s;
    629 
    630 	s = splusb();
    631 	SLIST_REMOVE(&usb_selevent.sel_klist, kn, knote, kn_selnext);
    632 	splx(s);
    633 }
    634 
    635 static int
    636 filt_usbread(struct knote *kn, long hint)
    637 {
    638 
    639 	if (usb_nevents == 0)
    640 		return (0);
    641 
    642 	kn->kn_data = sizeof(struct usb_event);
    643 	return (1);
    644 }
    645 
    646 static const struct filterops usbread_filtops =
    647 	{ 1, NULL, filt_usbrdetach, filt_usbread };
    648 
    649 int
    650 usbkqfilter(dev_t dev, struct knote *kn)
    651 {
    652 	struct klist *klist;
    653 	int s;
    654 
    655 	switch (kn->kn_filter) {
    656 	case EVFILT_READ:
    657 		if (minor(dev) != USB_DEV_MINOR)
    658 			return (1);
    659 		klist = &usb_selevent.sel_klist;
    660 		kn->kn_fop = &usbread_filtops;
    661 		break;
    662 
    663 	default:
    664 		return (1);
    665 	}
    666 
    667 	kn->kn_hook = NULL;
    668 
    669 	s = splusb();
    670 	SLIST_INSERT_HEAD(klist, kn, kn_selnext);
    671 	splx(s);
    672 
    673 	return (0);
    674 }
    675 
    676 /* Explore device tree from the root. */
    677 Static void
    678 usb_discover(void *v)
    679 {
    680 	struct usb_softc *sc = v;
    681 
    682 	DPRINTFN(2,("usb_discover\n"));
    683 #ifdef USB_DEBUG
    684 	if (usb_noexplore > 1)
    685 		return;
    686 #endif
    687 	/*
    688 	 * We need mutual exclusion while traversing the device tree,
    689 	 * but this is guaranteed since this function is only called
    690 	 * from the event thread for the controller.
    691 	 */
    692 	while (sc->sc_bus->needs_explore && !sc->sc_dying) {
    693 		sc->sc_bus->needs_explore = 0;
    694 		sc->sc_bus->root_hub->hub->explore(sc->sc_bus->root_hub);
    695 	}
    696 }
    697 
    698 void
    699 usb_needs_explore(usbd_device_handle dev)
    700 {
    701 	DPRINTFN(2,("usb_needs_explore\n"));
    702 	dev->bus->needs_explore = 1;
    703 	wakeup(&dev->bus->needs_explore);
    704 }
    705 
    706 void
    707 usb_needs_reattach(usbd_device_handle dev)
    708 {
    709 	DPRINTFN(2,("usb_needs_reattach\n"));
    710 	dev->powersrc->reattach = 1;
    711 	dev->bus->needs_explore = 1;
    712 	wakeup(&dev->bus->needs_explore);
    713 }
    714 
    715 /* Called at splusb() */
    716 int
    717 usb_get_next_event(struct usb_event *ue)
    718 {
    719 	struct usb_event_q *ueq;
    720 
    721 	if (usb_nevents <= 0)
    722 		return (0);
    723 	ueq = SIMPLEQ_FIRST(&usb_events);
    724 #ifdef DIAGNOSTIC
    725 	if (ueq == NULL) {
    726 		printf("usb: usb_nevents got out of sync! %d\n", usb_nevents);
    727 		usb_nevents = 0;
    728 		return (0);
    729 	}
    730 #endif
    731 	if (ue)
    732 		*ue = ueq->ue;
    733 	SIMPLEQ_REMOVE_HEAD(&usb_events, next);
    734 	usb_free_event((struct usb_event *)(void *)ueq);
    735 	usb_nevents--;
    736 	return (1);
    737 }
    738 
    739 void
    740 usbd_add_dev_event(int type, usbd_device_handle udev)
    741 {
    742 	struct usb_event *ue = usb_alloc_event();
    743 
    744 	usbd_fill_deviceinfo(udev, &ue->u.ue_device, USB_EVENT_IS_ATTACH(type));
    745 	usb_add_event(type, ue);
    746 }
    747 
    748 void
    749 usbd_add_drv_event(int type, usbd_device_handle udev, device_ptr_t dev)
    750 {
    751 	struct usb_event *ue = usb_alloc_event();
    752 
    753 	ue->u.ue_driver.ue_cookie = udev->cookie;
    754 	strncpy(ue->u.ue_driver.ue_devname, USBDEVPTRNAME(dev),
    755 	    sizeof ue->u.ue_driver.ue_devname);
    756 	usb_add_event(type, ue);
    757 }
    758 
    759 Static struct usb_event *
    760 usb_alloc_event(void)
    761 {
    762 	/* Yes, this is right; we allocate enough so that we can use it later */
    763 	return malloc(sizeof(struct usb_event_q), M_USBDEV, M_WAITOK|M_ZERO);
    764 }
    765 
    766 Static void
    767 usb_free_event(struct usb_event *uep)
    768 {
    769 	free(uep, M_USBDEV);
    770 }
    771 
    772 Static void
    773 usb_add_event(int type, struct usb_event *uep)
    774 {
    775 	struct usb_event_q *ueq;
    776 	struct timeval thetime;
    777 	int s;
    778 
    779 	microtime(&thetime);
    780 	/* Don't want to wait here inside splusb() */
    781 	ueq = (struct usb_event_q *)(void *)uep;
    782 	ueq->ue = *uep;
    783 	ueq->ue.ue_type = type;
    784 	TIMEVAL_TO_TIMESPEC(&thetime, &ueq->ue.ue_time);
    785 
    786 	s = splusb();
    787 	if (++usb_nevents >= USB_MAX_EVENTS) {
    788 		/* Too many queued events, drop an old one. */
    789 		DPRINTFN(-1,("usb: event dropped\n"));
    790 		(void)usb_get_next_event(0);
    791 	}
    792 	SIMPLEQ_INSERT_TAIL(&usb_events, ueq, next);
    793 	wakeup(&usb_events);
    794 	selnotify(&usb_selevent, 0);
    795 	if (usb_async_proc != NULL)
    796 		psignal(usb_async_proc, SIGIO);
    797 	splx(s);
    798 }
    799 
    800 void
    801 usb_schedsoftintr(usbd_bus_handle bus)
    802 {
    803 	DPRINTFN(10,("usb_schedsoftintr: polling=%d\n", bus->use_polling));
    804 #ifdef USB_USE_SOFTINTR
    805 	if (bus->use_polling) {
    806 		bus->methods->soft_intr(bus);
    807 	} else {
    808 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
    809 		softintr_schedule(bus->soft);
    810 #else
    811 		if (!callout_pending(&bus->softi))
    812 			callout_reset(&bus->softi, 0, bus->methods->soft_intr,
    813 			    bus);
    814 #endif /* __HAVE_GENERIC_SOFT_INTERRUPTS */
    815 	}
    816 #else
    817 	bus->methods->soft_intr(bus);
    818 #endif /* USB_USE_SOFTINTR */
    819 }
    820 
    821 int
    822 usb_activate(device_ptr_t self, enum devact act)
    823 {
    824 	struct usb_softc *sc = (struct usb_softc *)self;
    825 	usbd_device_handle dev = sc->sc_port.device;
    826 	int i, rv = 0;
    827 
    828 	switch (act) {
    829 	case DVACT_ACTIVATE:
    830 		return (EOPNOTSUPP);
    831 
    832 	case DVACT_DEACTIVATE:
    833 		sc->sc_dying = 1;
    834 		if (dev != NULL && dev->cdesc != NULL && dev->subdevs != NULL) {
    835 			for (i = 0; dev->subdevs[i]; i++)
    836 				rv |= config_deactivate(dev->subdevs[i]);
    837 		}
    838 		break;
    839 	}
    840 	return (rv);
    841 }
    842 
    843 int
    844 usb_detach(device_ptr_t self, int flags)
    845 {
    846 	struct usb_softc *sc = (struct usb_softc *)self;
    847 	struct usb_event *ue;
    848 
    849 	DPRINTF(("usb_detach: start\n"));
    850 
    851 	sc->sc_dying = 1;
    852 
    853 	/* Make all devices disconnect. */
    854 	if (sc->sc_port.device != NULL)
    855 		usb_disconnect_port(&sc->sc_port, self);
    856 
    857 	/* Kill off event thread. */
    858 	if (sc->sc_event_thread != NULL) {
    859 		wakeup(&sc->sc_bus->needs_explore);
    860 		if (tsleep(sc, PWAIT, "usbdet", hz * 60))
    861 			printf("%s: event thread didn't die\n",
    862 			       USBDEVNAME(sc->sc_dev));
    863 		DPRINTF(("usb_detach: event thread dead\n"));
    864 	}
    865 
    866 	usbd_finish();
    867 
    868 #ifdef USB_USE_SOFTINTR
    869 #ifdef __HAVE_GENERIC_SOFT_INTERRUPTS
    870 	if (sc->sc_bus->soft != NULL) {
    871 		softintr_disestablish(sc->sc_bus->soft);
    872 		sc->sc_bus->soft = NULL;
    873 	}
    874 #else
    875 	callout_stop(&sc->sc_bus->softi);
    876 #endif
    877 #endif
    878 
    879 	ue = usb_alloc_event();
    880 	ue->u.ue_ctrlr.ue_bus = USBDEVUNIT(sc->sc_dev);
    881 	usb_add_event(USB_EVENT_CTRLR_DETACH, ue);
    882 
    883 	return (0);
    884 }
    885