xref: /netbsd-src/sys/dev/usb/usbdi.c (revision a4ddc2c8fb9af816efe3b1c375a5530aef0e89e9)
1 /*	$NetBSD: usbdi.c,v 1.150 2013/01/22 13:27:59 jmcneill Exp $	*/
2 
3 /*
4  * Copyright (c) 1998, 2012 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@augustsson.net) at
9  * Carlstedt Research & Technology and Matthew R. Green (mrg@eterna.com.au).
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  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: usbdi.c,v 1.150 2013/01/22 13:27:59 jmcneill Exp $");
35 
36 #ifdef _KERNEL_OPT
37 #include "opt_compat_netbsd.h"
38 #endif
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/kernel.h>
43 #include <sys/device.h>
44 #include <sys/malloc.h>
45 #include <sys/proc.h>
46 #include <sys/bus.h>
47 #include <sys/cpu.h>
48 
49 #include <dev/usb/usb.h>
50 #include <dev/usb/usbdi.h>
51 #include <dev/usb/usbdi_util.h>
52 #include <dev/usb/usbdivar.h>
53 #include <dev/usb/usb_mem.h>
54 #include <dev/usb/usb_quirks.h>
55 
56 /* UTF-8 encoding stuff */
57 #include <fs/unicode.h>
58 
59 #ifdef USB_DEBUG
60 #define DPRINTF(x)	if (usbdebug) printf x
61 #define DPRINTFN(n,x)	if (usbdebug>(n)) printf x
62 extern int usbdebug;
63 #else
64 #define DPRINTF(x)
65 #define DPRINTFN(n,x)
66 #endif
67 
68 Static usbd_status usbd_ar_pipe(usbd_pipe_handle pipe);
69 Static void usbd_do_request_async_cb
70 	(usbd_xfer_handle, usbd_private_handle, usbd_status);
71 Static void usbd_start_next(usbd_pipe_handle pipe);
72 Static usbd_status usbd_open_pipe_ival
73 	(usbd_interface_handle, u_int8_t, u_int8_t, usbd_pipe_handle *, int);
74 
75 static inline int
76 usbd_xfer_isread(usbd_xfer_handle xfer)
77 {
78 	if (xfer->rqflags & URQ_REQUEST)
79 		return (xfer->request.bmRequestType & UT_READ);
80 	else
81 		return (xfer->pipe->endpoint->edesc->bEndpointAddress &
82 			UE_DIR_IN);
83 }
84 
85 #if defined(USB_DEBUG) || defined(EHCI_DEBUG)
86 void
87 usbd_dump_iface(struct usbd_interface *iface)
88 {
89 	printf("usbd_dump_iface: iface=%p\n", iface);
90 	if (iface == NULL)
91 		return;
92 	printf(" device=%p idesc=%p index=%d altindex=%d priv=%p\n",
93 	       iface->device, iface->idesc, iface->index, iface->altindex,
94 	       iface->priv);
95 }
96 
97 void
98 usbd_dump_device(struct usbd_device *dev)
99 {
100 	printf("usbd_dump_device: dev=%p\n", dev);
101 	if (dev == NULL)
102 		return;
103 	printf(" bus=%p default_pipe=%p\n", dev->bus, dev->default_pipe);
104 	printf(" address=%d config=%d depth=%d speed=%d self_powered=%d "
105 	       "power=%d langid=%d\n",
106 	       dev->address, dev->config, dev->depth, dev->speed,
107 	       dev->self_powered, dev->power, dev->langid);
108 }
109 
110 void
111 usbd_dump_endpoint(struct usbd_endpoint *endp)
112 {
113 	printf("usbd_dump_endpoint: endp=%p\n", endp);
114 	if (endp == NULL)
115 		return;
116 	printf(" edesc=%p refcnt=%d\n", endp->edesc, endp->refcnt);
117 	if (endp->edesc)
118 		printf(" bEndpointAddress=0x%02x\n",
119 		       endp->edesc->bEndpointAddress);
120 }
121 
122 void
123 usbd_dump_queue(usbd_pipe_handle pipe)
124 {
125 	usbd_xfer_handle xfer;
126 
127 	printf("usbd_dump_queue: pipe=%p\n", pipe);
128 	SIMPLEQ_FOREACH(xfer, &pipe->queue, next) {
129 		printf("  xfer=%p\n", xfer);
130 	}
131 }
132 
133 void
134 usbd_dump_pipe(usbd_pipe_handle pipe)
135 {
136 	printf("usbd_dump_pipe: pipe=%p\n", pipe);
137 	if (pipe == NULL)
138 		return;
139 	usbd_dump_iface(pipe->iface);
140 	usbd_dump_device(pipe->device);
141 	usbd_dump_endpoint(pipe->endpoint);
142 	printf(" (usbd_dump_pipe:)\n refcnt=%d running=%d aborting=%d\n",
143 	       pipe->refcnt, pipe->running, pipe->aborting);
144 	printf(" intrxfer=%p, repeat=%d, interval=%d\n",
145 	       pipe->intrxfer, pipe->repeat, pipe->interval);
146 }
147 #endif
148 
149 usbd_status
150 usbd_open_pipe(usbd_interface_handle iface, u_int8_t address,
151 	       u_int8_t flags, usbd_pipe_handle *pipe)
152 {
153 	return (usbd_open_pipe_ival(iface, address, flags, pipe,
154 				    USBD_DEFAULT_INTERVAL));
155 }
156 
157 usbd_status
158 usbd_open_pipe_ival(usbd_interface_handle iface, u_int8_t address,
159 		    u_int8_t flags, usbd_pipe_handle *pipe, int ival)
160 {
161 	usbd_pipe_handle p;
162 	struct usbd_endpoint *ep;
163 	usbd_status err;
164 	int i;
165 
166 	DPRINTFN(3,("usbd_open_pipe: iface=%p address=0x%x flags=0x%x\n",
167 		    iface, address, flags));
168 
169 	for (i = 0; i < iface->idesc->bNumEndpoints; i++) {
170 		ep = &iface->endpoints[i];
171 		if (ep->edesc == NULL)
172 			return (USBD_IOERROR);
173 		if (ep->edesc->bEndpointAddress == address)
174 			goto found;
175 	}
176 	return (USBD_BAD_ADDRESS);
177  found:
178 	if ((flags & USBD_EXCLUSIVE_USE) && ep->refcnt != 0)
179 		return (USBD_IN_USE);
180 	err = usbd_setup_pipe_flags(iface->device, iface, ep, ival, &p, flags);
181 	if (err)
182 		return (err);
183 	LIST_INSERT_HEAD(&iface->pipes, p, next);
184 	*pipe = p;
185 	return (USBD_NORMAL_COMPLETION);
186 }
187 
188 usbd_status
189 usbd_open_pipe_intr(usbd_interface_handle iface, u_int8_t address,
190 		    u_int8_t flags, usbd_pipe_handle *pipe,
191 		    usbd_private_handle priv, void *buffer, u_int32_t len,
192 		    usbd_callback cb, int ival)
193 {
194 	usbd_status err;
195 	usbd_xfer_handle xfer;
196 	usbd_pipe_handle ipipe;
197 
198 	DPRINTFN(3,("usbd_open_pipe_intr: address=0x%x flags=0x%x len=%d\n",
199 		    address, flags, len));
200 
201 	err = usbd_open_pipe_ival(iface, address,
202 				  USBD_EXCLUSIVE_USE | (flags & USBD_MPSAFE),
203 				  &ipipe, ival);
204 	if (err)
205 		return (err);
206 	xfer = usbd_alloc_xfer(iface->device);
207 	if (xfer == NULL) {
208 		err = USBD_NOMEM;
209 		goto bad1;
210 	}
211 	usbd_setup_xfer(xfer, ipipe, priv, buffer, len, flags,
212 	    USBD_NO_TIMEOUT, cb);
213 	ipipe->intrxfer = xfer;
214 	ipipe->repeat = 1;
215 	err = usbd_transfer(xfer);
216 	*pipe = ipipe;
217 	if (err != USBD_IN_PROGRESS)
218 		goto bad2;
219 	return (USBD_NORMAL_COMPLETION);
220 
221  bad2:
222 	ipipe->intrxfer = NULL;
223 	ipipe->repeat = 0;
224 	usbd_free_xfer(xfer);
225  bad1:
226 	usbd_close_pipe(ipipe);
227 	return (err);
228 }
229 
230 usbd_status
231 usbd_close_pipe(usbd_pipe_handle pipe)
232 {
233 	int s;
234 
235 #ifdef DIAGNOSTIC
236 	if (pipe == NULL) {
237 		printf("usbd_close_pipe: pipe==NULL\n");
238 		return (USBD_NORMAL_COMPLETION);
239 	}
240 #endif
241 
242 	usbd_lock_pipe(pipe);
243 	if (--pipe->refcnt != 0) {
244 		usbd_unlock_pipe(pipe);
245 		return (USBD_NORMAL_COMPLETION);
246 	}
247 	if (! SIMPLEQ_EMPTY(&pipe->queue)) {
248 		usbd_unlock_pipe(pipe);
249 		return (USBD_PENDING_REQUESTS);
250 	}
251 	LIST_REMOVE(pipe, next);
252 	pipe->endpoint->refcnt--;
253 	pipe->methods->close(pipe);
254 	usbd_unlock_pipe(pipe);
255 	if (pipe->intrxfer != NULL)
256 		usbd_free_xfer(pipe->intrxfer);
257 	free(pipe, M_USB);
258 	return (USBD_NORMAL_COMPLETION);
259 }
260 
261 usbd_status
262 usbd_transfer(usbd_xfer_handle xfer)
263 {
264 	usbd_pipe_handle pipe = xfer->pipe;
265 	usb_dma_t *dmap = &xfer->dmabuf;
266 	usbd_status err;
267 	unsigned int size, flags;
268 	int s;
269 
270 	DPRINTFN(5,("usbd_transfer: xfer=%p, flags=%#x, pipe=%p, running=%d\n",
271 		    xfer, xfer->flags, pipe, pipe->running));
272 
273 #ifdef USB_DEBUG
274 	if (usbdebug > 5)
275 		usbd_dump_queue(pipe);
276 #endif
277 	xfer->done = 0;
278 
279 	if (pipe->aborting)
280 		return (USBD_CANCELLED);
281 
282 	size = xfer->length;
283 	/* If there is no buffer, allocate one. */
284 	if (!(xfer->rqflags & URQ_DEV_DMABUF) && size != 0) {
285 		struct usbd_bus *bus = pipe->device->bus;
286 
287 #ifdef DIAGNOSTIC
288 		if (xfer->rqflags & URQ_AUTO_DMABUF)
289 			printf("usbd_transfer: has old buffer!\n");
290 #endif
291 		err = bus->methods->allocm(bus, dmap, size);
292 		if (err)
293 			return (err);
294 		xfer->rqflags |= URQ_AUTO_DMABUF;
295 	}
296 
297 	flags = xfer->flags;
298 
299 	/* Copy data if going out. */
300 	if (!(flags & USBD_NO_COPY) && size != 0 && !usbd_xfer_isread(xfer))
301 		memcpy(KERNADDR(dmap, 0), xfer->buffer, size);
302 
303 	/* xfer is not valid after the transfer method unless synchronous */
304 	err = pipe->methods->transfer(xfer);
305 
306 	if (err != USBD_IN_PROGRESS && err) {
307 		/* The transfer has not been queued, so free buffer. */
308 		if (xfer->rqflags & URQ_AUTO_DMABUF) {
309 			struct usbd_bus *bus = pipe->device->bus;
310 
311 			bus->methods->freem(bus, &xfer->dmabuf);
312 			xfer->rqflags &= ~URQ_AUTO_DMABUF;
313 		}
314 	}
315 
316 	if (!(flags & USBD_SYNCHRONOUS))
317 		return (err);
318 
319 	/* Sync transfer, wait for completion. */
320 	if (err != USBD_IN_PROGRESS)
321 		return (err);
322 	usbd_lock_pipe(pipe);
323 	while (!xfer->done) {
324 		if (pipe->device->bus->use_polling)
325 			panic("usbd_transfer: not done");
326 
327 		err = 0;
328 		if ((flags & USBD_SYNCHRONOUS_SIG) != 0) {
329 			if (pipe->device->bus->lock)
330 				err = cv_wait_sig(&xfer->cv, pipe->device->bus->lock);
331 			else
332 				err = tsleep(xfer, PZERO|PCATCH, "usbsyn", 0);
333 		} else {
334 			if (pipe->device->bus->lock)
335 				cv_wait(&xfer->cv, pipe->device->bus->lock);
336 			else
337 				err = tsleep(xfer, PRIBIO, "usbsyn", 0);
338 		}
339 		if (err)
340 			break;
341 	}
342 	usbd_unlock_pipe(pipe);
343 	return (xfer->status);
344 }
345 
346 /* Like usbd_transfer(), but waits for completion. */
347 usbd_status
348 usbd_sync_transfer(usbd_xfer_handle xfer)
349 {
350 	xfer->flags |= USBD_SYNCHRONOUS;
351 	return (usbd_transfer(xfer));
352 }
353 
354 /* Like usbd_transfer(), but waits for completion and listens for signals. */
355 usbd_status
356 usbd_sync_transfer_sig(usbd_xfer_handle xfer)
357 {
358 	xfer->flags |= USBD_SYNCHRONOUS | USBD_SYNCHRONOUS_SIG;
359 	return (usbd_transfer(xfer));
360 }
361 
362 void *
363 usbd_alloc_buffer(usbd_xfer_handle xfer, u_int32_t size)
364 {
365 	struct usbd_bus *bus = xfer->device->bus;
366 	usbd_status err;
367 
368 #ifdef DIAGNOSTIC
369 	if (xfer->rqflags & (URQ_DEV_DMABUF | URQ_AUTO_DMABUF))
370 		printf("usbd_alloc_buffer: xfer already has a buffer\n");
371 #endif
372 	err = bus->methods->allocm(bus, &xfer->dmabuf, size);
373 	if (err)
374 		return (NULL);
375 	xfer->rqflags |= URQ_DEV_DMABUF;
376 	return (KERNADDR(&xfer->dmabuf, 0));
377 }
378 
379 void
380 usbd_free_buffer(usbd_xfer_handle xfer)
381 {
382 #ifdef DIAGNOSTIC
383 	if (!(xfer->rqflags & (URQ_DEV_DMABUF | URQ_AUTO_DMABUF))) {
384 		printf("usbd_free_buffer: no buffer\n");
385 		return;
386 	}
387 #endif
388 	xfer->rqflags &= ~(URQ_DEV_DMABUF | URQ_AUTO_DMABUF);
389 	xfer->device->bus->methods->freem(xfer->device->bus, &xfer->dmabuf);
390 }
391 
392 void *
393 usbd_get_buffer(usbd_xfer_handle xfer)
394 {
395 	if (!(xfer->rqflags & URQ_DEV_DMABUF))
396 		return (0);
397 	return (KERNADDR(&xfer->dmabuf, 0));
398 }
399 
400 usbd_xfer_handle
401 usbd_alloc_xfer(usbd_device_handle dev)
402 {
403 	usbd_xfer_handle xfer;
404 
405 	xfer = dev->bus->methods->allocx(dev->bus);
406 	if (xfer == NULL)
407 		return (NULL);
408 	xfer->device = dev;
409 	callout_init(&xfer->timeout_handle,
410 	    dev->bus->methods->get_lock ? CALLOUT_MPSAFE : 0);
411 	cv_init(&xfer->cv, "usbxfer");
412 	cv_init(&xfer->hccv, "usbhcxfer");
413 	DPRINTFN(5,("usbd_alloc_xfer() = %p\n", xfer));
414 	return (xfer);
415 }
416 
417 usbd_status
418 usbd_free_xfer(usbd_xfer_handle xfer)
419 {
420 	DPRINTFN(5,("usbd_free_xfer: %p\n", xfer));
421 	if (xfer->rqflags & (URQ_DEV_DMABUF | URQ_AUTO_DMABUF))
422 		usbd_free_buffer(xfer);
423 #if defined(DIAGNOSTIC)
424 	if (callout_pending(&xfer->timeout_handle)) {
425 		callout_stop(&xfer->timeout_handle);
426 		printf("usbd_free_xfer: timeout_handle pending\n");
427 	}
428 #endif
429 	cv_destroy(&xfer->cv);
430 	cv_destroy(&xfer->hccv);
431 	xfer->device->bus->methods->freex(xfer->device->bus, xfer);
432 	return (USBD_NORMAL_COMPLETION);
433 }
434 
435 void
436 usbd_setup_xfer(usbd_xfer_handle xfer, usbd_pipe_handle pipe,
437 		usbd_private_handle priv, void *buffer, u_int32_t length,
438 		u_int16_t flags, u_int32_t timeout,
439 		usbd_callback callback)
440 {
441 	xfer->pipe = pipe;
442 	xfer->priv = priv;
443 	xfer->buffer = buffer;
444 	xfer->length = length;
445 	xfer->actlen = 0;
446 	xfer->flags = flags;
447 	xfer->timeout = timeout;
448 	xfer->status = USBD_NOT_STARTED;
449 	xfer->callback = callback;
450 	xfer->rqflags &= ~URQ_REQUEST;
451 	xfer->nframes = 0;
452 }
453 
454 void
455 usbd_setup_default_xfer(usbd_xfer_handle xfer, usbd_device_handle dev,
456 			usbd_private_handle priv, u_int32_t timeout,
457 			usb_device_request_t *req, void *buffer,
458 			u_int32_t length, u_int16_t flags,
459 			usbd_callback callback)
460 {
461 	xfer->pipe = dev->default_pipe;
462 	xfer->priv = priv;
463 	xfer->buffer = buffer;
464 	xfer->length = length;
465 	xfer->actlen = 0;
466 	xfer->flags = flags;
467 	xfer->timeout = timeout;
468 	xfer->status = USBD_NOT_STARTED;
469 	xfer->callback = callback;
470 	xfer->request = *req;
471 	xfer->rqflags |= URQ_REQUEST;
472 	xfer->nframes = 0;
473 }
474 
475 void
476 usbd_setup_isoc_xfer(usbd_xfer_handle xfer, usbd_pipe_handle pipe,
477 		     usbd_private_handle priv, u_int16_t *frlengths,
478 		     u_int32_t nframes, u_int16_t flags, usbd_callback callback)
479 {
480 	xfer->pipe = pipe;
481 	xfer->priv = priv;
482 	xfer->buffer = 0;
483 	xfer->length = 0;
484 	xfer->actlen = 0;
485 	xfer->flags = flags;
486 	xfer->timeout = USBD_NO_TIMEOUT;
487 	xfer->status = USBD_NOT_STARTED;
488 	xfer->callback = callback;
489 	xfer->rqflags &= ~URQ_REQUEST;
490 	xfer->frlengths = frlengths;
491 	xfer->nframes = nframes;
492 }
493 
494 void
495 usbd_get_xfer_status(usbd_xfer_handle xfer, usbd_private_handle *priv,
496 		     void **buffer, u_int32_t *count, usbd_status *status)
497 {
498 	if (priv != NULL)
499 		*priv = xfer->priv;
500 	if (buffer != NULL)
501 		*buffer = xfer->buffer;
502 	if (count != NULL)
503 		*count = xfer->actlen;
504 	if (status != NULL)
505 		*status = xfer->status;
506 }
507 
508 usb_config_descriptor_t *
509 usbd_get_config_descriptor(usbd_device_handle dev)
510 {
511 #ifdef DIAGNOSTIC
512 	if (dev == NULL) {
513 		printf("usbd_get_config_descriptor: dev == NULL\n");
514 		return (NULL);
515 	}
516 #endif
517 	return (dev->cdesc);
518 }
519 
520 usb_interface_descriptor_t *
521 usbd_get_interface_descriptor(usbd_interface_handle iface)
522 {
523 #ifdef DIAGNOSTIC
524 	if (iface == NULL) {
525 		printf("usbd_get_interface_descriptor: dev == NULL\n");
526 		return (NULL);
527 	}
528 #endif
529 	return (iface->idesc);
530 }
531 
532 usb_device_descriptor_t *
533 usbd_get_device_descriptor(usbd_device_handle dev)
534 {
535 	return (&dev->ddesc);
536 }
537 
538 usb_endpoint_descriptor_t *
539 usbd_interface2endpoint_descriptor(usbd_interface_handle iface, u_int8_t index)
540 {
541 	if (index >= iface->idesc->bNumEndpoints)
542 		return (0);
543 	return (iface->endpoints[index].edesc);
544 }
545 
546 /* Some drivers may wish to abort requests on the default pipe, *
547  * but there is no mechanism for getting a handle on it.        */
548 usbd_status
549 usbd_abort_default_pipe(struct usbd_device *device)
550 {
551 
552 	return usbd_abort_pipe(device->default_pipe);
553 }
554 
555 usbd_status
556 usbd_abort_pipe(usbd_pipe_handle pipe)
557 {
558 	usbd_status err;
559 	int s;
560 	usbd_xfer_handle intrxfer = pipe->intrxfer;
561 
562 #ifdef DIAGNOSTIC
563 	if (pipe == NULL) {
564 		printf("usbd_abort_pipe: pipe==NULL\n");
565 		return (USBD_NORMAL_COMPLETION);
566 	}
567 #endif
568 	usbd_lock_pipe(pipe);
569 	err = usbd_ar_pipe(pipe);
570 	usbd_unlock_pipe(pipe);
571 	if (pipe->intrxfer != intrxfer)
572 		usbd_free_xfer(intrxfer);
573 	return (err);
574 }
575 
576 usbd_status
577 usbd_clear_endpoint_stall(usbd_pipe_handle pipe)
578 {
579 	usbd_device_handle dev = pipe->device;
580 	usb_device_request_t req;
581 	usbd_status err;
582 
583 	DPRINTFN(8, ("usbd_clear_endpoint_stall\n"));
584 
585 	/*
586 	 * Clearing en endpoint stall resets the endpoint toggle, so
587 	 * do the same to the HC toggle.
588 	 */
589 	pipe->methods->cleartoggle(pipe);
590 
591 	req.bmRequestType = UT_WRITE_ENDPOINT;
592 	req.bRequest = UR_CLEAR_FEATURE;
593 	USETW(req.wValue, UF_ENDPOINT_HALT);
594 	USETW(req.wIndex, pipe->endpoint->edesc->bEndpointAddress);
595 	USETW(req.wLength, 0);
596 	err = usbd_do_request(dev, &req, 0);
597 #if 0
598 XXX should we do this?
599 	if (!err) {
600 		pipe->state = USBD_PIPE_ACTIVE;
601 		/* XXX activate pipe */
602 	}
603 #endif
604 	return (err);
605 }
606 
607 void
608 usbd_clear_endpoint_stall_async_cb(void *arg)
609 {
610 	usbd_pipe_handle pipe = arg;
611 	usbd_device_handle dev = pipe->device;
612 	usb_device_request_t req;
613 
614 	pipe->methods->cleartoggle(pipe);
615 
616 	req.bmRequestType = UT_WRITE_ENDPOINT;
617 	req.bRequest = UR_CLEAR_FEATURE;
618 	USETW(req.wValue, UF_ENDPOINT_HALT);
619 	USETW(req.wIndex, pipe->endpoint->edesc->bEndpointAddress);
620 	USETW(req.wLength, 0);
621 	(void)usbd_do_request_async(dev, &req, 0);
622 }
623 
624 void
625 usbd_clear_endpoint_stall_async(usbd_pipe_handle pipe)
626 {
627 
628 	usb_add_task(pipe->device, &pipe->async_task, USB_TASKQ_DRIVER);
629 }
630 
631 void
632 usbd_clear_endpoint_toggle(usbd_pipe_handle pipe)
633 {
634 	pipe->methods->cleartoggle(pipe);
635 }
636 
637 usbd_status
638 usbd_endpoint_count(usbd_interface_handle iface, u_int8_t *count)
639 {
640 #ifdef DIAGNOSTIC
641 	if (iface == NULL || iface->idesc == NULL) {
642 		printf("usbd_endpoint_count: NULL pointer\n");
643 		return (USBD_INVAL);
644 	}
645 #endif
646 	*count = iface->idesc->bNumEndpoints;
647 	return (USBD_NORMAL_COMPLETION);
648 }
649 
650 usbd_status
651 usbd_interface_count(usbd_device_handle dev, u_int8_t *count)
652 {
653 	if (dev->cdesc == NULL)
654 		return (USBD_NOT_CONFIGURED);
655 	*count = dev->cdesc->bNumInterface;
656 	return (USBD_NORMAL_COMPLETION);
657 }
658 
659 void
660 usbd_interface2device_handle(usbd_interface_handle iface,
661 			     usbd_device_handle *dev)
662 {
663 	*dev = iface->device;
664 }
665 
666 usbd_status
667 usbd_device2interface_handle(usbd_device_handle dev,
668 			     u_int8_t ifaceno, usbd_interface_handle *iface)
669 {
670 	if (dev->cdesc == NULL)
671 		return (USBD_NOT_CONFIGURED);
672 	if (ifaceno >= dev->cdesc->bNumInterface)
673 		return (USBD_INVAL);
674 	*iface = &dev->ifaces[ifaceno];
675 	return (USBD_NORMAL_COMPLETION);
676 }
677 
678 usbd_device_handle
679 usbd_pipe2device_handle(usbd_pipe_handle pipe)
680 {
681 	return (pipe->device);
682 }
683 
684 /* XXXX use altno */
685 usbd_status
686 usbd_set_interface(usbd_interface_handle iface, int altidx)
687 {
688 	usb_device_request_t req;
689 	usbd_status err;
690 	void *endpoints;
691 
692 	if (LIST_FIRST(&iface->pipes) != 0)
693 		return (USBD_IN_USE);
694 
695 	endpoints = iface->endpoints;
696 	err = usbd_fill_iface_data(iface->device, iface->index, altidx);
697 	if (err)
698 		return (err);
699 
700 	/* new setting works, we can free old endpoints */
701 	if (endpoints != NULL)
702 		free(endpoints, M_USB);
703 
704 #ifdef DIAGNOSTIC
705 	if (iface->idesc == NULL) {
706 		printf("usbd_set_interface: NULL pointer\n");
707 		return (USBD_INVAL);
708 	}
709 #endif
710 
711 	req.bmRequestType = UT_WRITE_INTERFACE;
712 	req.bRequest = UR_SET_INTERFACE;
713 	USETW(req.wValue, iface->idesc->bAlternateSetting);
714 	USETW(req.wIndex, iface->idesc->bInterfaceNumber);
715 	USETW(req.wLength, 0);
716 	return (usbd_do_request(iface->device, &req, 0));
717 }
718 
719 int
720 usbd_get_no_alts(usb_config_descriptor_t *cdesc, int ifaceno)
721 {
722 	char *p = (char *)cdesc;
723 	char *end = p + UGETW(cdesc->wTotalLength);
724 	usb_interface_descriptor_t *d;
725 	int n;
726 
727 	for (n = 0; p < end; p += d->bLength) {
728 		d = (usb_interface_descriptor_t *)p;
729 		if (p + d->bLength <= end &&
730 		    d->bDescriptorType == UDESC_INTERFACE &&
731 		    d->bInterfaceNumber == ifaceno)
732 			n++;
733 	}
734 	return (n);
735 }
736 
737 int
738 usbd_get_interface_altindex(usbd_interface_handle iface)
739 {
740 	return (iface->altindex);
741 }
742 
743 usbd_status
744 usbd_get_interface(usbd_interface_handle iface, u_int8_t *aiface)
745 {
746 	usb_device_request_t req;
747 
748 	req.bmRequestType = UT_READ_INTERFACE;
749 	req.bRequest = UR_GET_INTERFACE;
750 	USETW(req.wValue, 0);
751 	USETW(req.wIndex, iface->idesc->bInterfaceNumber);
752 	USETW(req.wLength, 1);
753 	return (usbd_do_request(iface->device, &req, aiface));
754 }
755 
756 /*** Internal routines ***/
757 
758 /* Dequeue all pipe operations, called at splusb(). */
759 Static usbd_status
760 usbd_ar_pipe(usbd_pipe_handle pipe)
761 {
762 	usbd_xfer_handle xfer;
763 
764 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
765 
766 	DPRINTFN(2,("usbd_ar_pipe: pipe=%p\n", pipe));
767 #ifdef USB_DEBUG
768 	if (usbdebug > 5)
769 		usbd_dump_queue(pipe);
770 #endif
771 	pipe->repeat = 0;
772 	pipe->aborting = 1;
773 	while ((xfer = SIMPLEQ_FIRST(&pipe->queue)) != NULL) {
774 		DPRINTFN(2,("usbd_ar_pipe: pipe=%p xfer=%p (methods=%p)\n",
775 			    pipe, xfer, pipe->methods));
776 		/* Make the HC abort it (and invoke the callback). */
777 		pipe->methods->abort(xfer);
778 		/* XXX only for non-0 usbd_clear_endpoint_stall(pipe); */
779 	}
780 	pipe->aborting = 0;
781 	return (USBD_NORMAL_COMPLETION);
782 }
783 
784 /* Called with USB lock held. */
785 void
786 usb_transfer_complete(usbd_xfer_handle xfer)
787 {
788 	usbd_pipe_handle pipe = xfer->pipe;
789 	usb_dma_t *dmap = &xfer->dmabuf;
790 	int sync = xfer->flags & USBD_SYNCHRONOUS;
791 	int erred = xfer->status == USBD_CANCELLED ||
792 	    xfer->status == USBD_TIMEOUT;
793 	int repeat, polling;
794 
795 	DPRINTFN(5, ("usb_transfer_complete: pipe=%p xfer=%p status=%d "
796 		     "actlen=%d\n", pipe, xfer, xfer->status, xfer->actlen));
797 
798 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
799 
800 #ifdef DIAGNOSTIC
801 	if (xfer->busy_free != XFER_ONQU) {
802 		printf("usb_transfer_complete: xfer=%p not queued 0x%08x\n",
803 		       xfer, xfer->busy_free);
804 	}
805 #endif
806 
807 #ifdef DIAGNOSTIC
808 	if (pipe == NULL) {
809 		printf("usb_transfer_complete: pipe==0, xfer=%p\n", xfer);
810 		return;
811 	}
812 #endif
813 	repeat = pipe->repeat;
814 	polling = pipe->device->bus->use_polling;
815 	/* XXXX */
816 	if (polling)
817 		pipe->running = 0;
818 
819 	if (!(xfer->flags & USBD_NO_COPY) && xfer->actlen != 0 &&
820 	    usbd_xfer_isread(xfer)) {
821 #ifdef DIAGNOSTIC
822 		if (xfer->actlen > xfer->length) {
823 			printf("%s: actlen (%d) > len (%d)\n", __func__,
824 			       xfer->actlen, xfer->length);
825 			xfer->actlen = xfer->length;
826 		}
827 #endif
828 		memcpy(xfer->buffer, KERNADDR(dmap, 0), xfer->actlen);
829 	}
830 
831 	/* if we allocated the buffer in usbd_transfer() we free it here. */
832 	if (xfer->rqflags & URQ_AUTO_DMABUF) {
833 		if (!repeat) {
834 			struct usbd_bus *bus = pipe->device->bus;
835 			bus->methods->freem(bus, dmap);
836 			xfer->rqflags &= ~URQ_AUTO_DMABUF;
837 		}
838 	}
839 
840 	if (!repeat) {
841 		/* Remove request from queue. */
842 
843 		KASSERTMSG(!SIMPLEQ_EMPTY(&pipe->queue),
844 		    "pipe %p is empty, but xfer %p wants to complete", pipe,
845 		     xfer);
846 #ifdef DIAGNOSTIC
847 		if (xfer != SIMPLEQ_FIRST(&pipe->queue))
848 			printf("%s: bad dequeue %p != %p\n", __func__,
849 			       xfer, SIMPLEQ_FIRST(&pipe->queue));
850 		xfer->busy_free = XFER_BUSY;
851 #endif
852 		SIMPLEQ_REMOVE_HEAD(&pipe->queue, next);
853 	}
854 	DPRINTFN(5,("usb_transfer_complete: repeat=%d new head=%p\n",
855 		    repeat, SIMPLEQ_FIRST(&pipe->queue)));
856 
857 	/* Count completed transfers. */
858 	++pipe->device->bus->stats.uds_requests
859 		[pipe->endpoint->edesc->bmAttributes & UE_XFERTYPE];
860 
861 	xfer->done = 1;
862 	if (!xfer->status && xfer->actlen < xfer->length &&
863 	    !(xfer->flags & USBD_SHORT_XFER_OK)) {
864 		DPRINTFN(-1,("usb_transfer_complete: short transfer %d<%d\n",
865 			     xfer->actlen, xfer->length));
866 		xfer->status = USBD_SHORT_XFER;
867 	}
868 
869 	if (repeat) {
870 		if (xfer->callback) {
871 			if (pipe->device->bus->lock)
872 				mutex_exit(pipe->device->bus->lock);
873 
874 			if (!(pipe->flags & USBD_MPSAFE))
875 				KERNEL_LOCK(1, curlwp);
876 			xfer->callback(xfer, xfer->priv, xfer->status);
877 			if (!(pipe->flags & USBD_MPSAFE))
878 				KERNEL_UNLOCK_ONE(curlwp);
879 
880 			if (pipe->device->bus->lock)
881 				mutex_enter(pipe->device->bus->lock);
882 		}
883 		pipe->methods->done(xfer);
884 	} else {
885 		pipe->methods->done(xfer);
886 		if (xfer->callback) {
887 			if (pipe->device->bus->lock)
888 				mutex_exit(pipe->device->bus->lock);
889 
890 			if (!(pipe->flags & USBD_MPSAFE))
891 				KERNEL_LOCK(1, curlwp);
892 			xfer->callback(xfer, xfer->priv, xfer->status);
893 			if (!(pipe->flags & USBD_MPSAFE))
894 				KERNEL_UNLOCK_ONE(curlwp);
895 
896 			if (pipe->device->bus->lock)
897 				mutex_enter(pipe->device->bus->lock);
898 		}
899 	}
900 
901 	if (sync && !polling) {
902 		if (pipe->device->bus->lock)
903 			cv_broadcast(&xfer->cv);
904 		else
905 			wakeup(xfer);	/* XXXSMP ok */
906 	}
907 
908 	if (!repeat) {
909 		/* XXX should we stop the queue on all errors? */
910 		if (erred && pipe->iface != NULL)	/* not control pipe */
911 			pipe->running = 0;
912 		else
913 			usbd_start_next(pipe);
914 	}
915 }
916 
917 /* Called with USB lock held. */
918 usbd_status
919 usb_insert_transfer(usbd_xfer_handle xfer)
920 {
921 	usbd_pipe_handle pipe = xfer->pipe;
922 	usbd_status err;
923 
924 	DPRINTFN(5,("usb_insert_transfer: pipe=%p running=%d timeout=%d\n",
925 		    pipe, pipe->running, xfer->timeout));
926 
927 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
928 
929 #ifdef DIAGNOSTIC
930 	if (xfer->busy_free != XFER_BUSY) {
931 		printf("usb_insert_transfer: xfer=%p not busy 0x%08x\n",
932 		       xfer, xfer->busy_free);
933 		return (USBD_INVAL);
934 	}
935 	xfer->busy_free = XFER_ONQU;
936 #endif
937 	SIMPLEQ_INSERT_TAIL(&pipe->queue, xfer, next);
938 	if (pipe->running)
939 		err = USBD_IN_PROGRESS;
940 	else {
941 		pipe->running = 1;
942 		err = USBD_NORMAL_COMPLETION;
943 	}
944 	return (err);
945 }
946 
947 /* Called with USB lock held. */
948 void
949 usbd_start_next(usbd_pipe_handle pipe)
950 {
951 	usbd_xfer_handle xfer;
952 	usbd_status err;
953 
954 #ifdef DIAGNOSTIC
955 	if (pipe == NULL) {
956 		printf("usbd_start_next: pipe == NULL\n");
957 		return;
958 	}
959 	if (pipe->methods == NULL || pipe->methods->start == NULL) {
960 		printf("usbd_start_next: pipe=%p no start method\n", pipe);
961 		return;
962 	}
963 #endif
964 
965 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
966 
967 	/* Get next request in queue. */
968 	xfer = SIMPLEQ_FIRST(&pipe->queue);
969 	DPRINTFN(5, ("usbd_start_next: pipe=%p, xfer=%p\n", pipe, xfer));
970 	if (xfer == NULL) {
971 		pipe->running = 0;
972 	} else {
973 		if (pipe->device->bus->lock)
974 			mutex_exit(pipe->device->bus->lock);
975 		err = pipe->methods->start(xfer);
976 		if (pipe->device->bus->lock)
977 			mutex_enter(pipe->device->bus->lock);
978 		if (err != USBD_IN_PROGRESS) {
979 			printf("usbd_start_next: error=%d\n", err);
980 			pipe->running = 0;
981 			/* XXX do what? */
982 		}
983 	}
984 
985 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
986 }
987 
988 usbd_status
989 usbd_do_request(usbd_device_handle dev, usb_device_request_t *req, void *data)
990 {
991 	return (usbd_do_request_flags(dev, req, data, 0, 0,
992 				      USBD_DEFAULT_TIMEOUT));
993 }
994 
995 usbd_status
996 usbd_do_request_flags(usbd_device_handle dev, usb_device_request_t *req,
997 		      void *data, u_int16_t flags, int *actlen, u_int32_t timo)
998 {
999 	return (usbd_do_request_flags_pipe(dev, dev->default_pipe, req,
1000 					   data, flags, actlen, timo));
1001 }
1002 
1003 usbd_status
1004 usbd_do_request_flags_pipe(usbd_device_handle dev, usbd_pipe_handle pipe,
1005 	usb_device_request_t *req, void *data, u_int16_t flags, int *actlen,
1006 	u_int32_t timeout)
1007 {
1008 	usbd_xfer_handle xfer;
1009 	usbd_status err;
1010 
1011 #ifdef DIAGNOSTIC
1012 	if (cpu_intr_p() || cpu_softintr_p()) {
1013 		printf("usbd_do_request: not in process context\n");
1014 		return (USBD_INVAL);
1015 	}
1016 #endif
1017 
1018 	xfer = usbd_alloc_xfer(dev);
1019 	if (xfer == NULL)
1020 		return (USBD_NOMEM);
1021 	usbd_setup_default_xfer(xfer, dev, 0, timeout, req,
1022 				data, UGETW(req->wLength), flags, 0);
1023 	xfer->pipe = pipe;
1024 	err = usbd_sync_transfer(xfer);
1025 #if defined(USB_DEBUG) || defined(DIAGNOSTIC)
1026 	if (xfer->actlen > xfer->length) {
1027 		DPRINTF(("%s: overrun addr=%d type=0x%02x req=0x"
1028 			 "%02x val=%d index=%d rlen=%d length=%d actlen=%d\n",
1029 			 __func__, dev->address, xfer->request.bmRequestType,
1030 			 xfer->request.bRequest, UGETW(xfer->request.wValue),
1031 			 UGETW(xfer->request.wIndex),
1032 			 UGETW(xfer->request.wLength),
1033 			 xfer->length, xfer->actlen));
1034 	}
1035 #endif
1036 	if (actlen != NULL)
1037 		*actlen = xfer->actlen;
1038 	if (err == USBD_STALLED) {
1039 		/*
1040 		 * The control endpoint has stalled.  Control endpoints
1041 		 * should not halt, but some may do so anyway so clear
1042 		 * any halt condition.
1043 		 */
1044 		usb_device_request_t treq;
1045 		usb_status_t status;
1046 		u_int16_t s;
1047 		usbd_status nerr;
1048 
1049 		treq.bmRequestType = UT_READ_ENDPOINT;
1050 		treq.bRequest = UR_GET_STATUS;
1051 		USETW(treq.wValue, 0);
1052 		USETW(treq.wIndex, 0);
1053 		USETW(treq.wLength, sizeof(usb_status_t));
1054 		usbd_setup_default_xfer(xfer, dev, 0, USBD_DEFAULT_TIMEOUT,
1055 					   &treq, &status,sizeof(usb_status_t),
1056 					   0, 0);
1057 		nerr = usbd_sync_transfer(xfer);
1058 		if (nerr)
1059 			goto bad;
1060 		s = UGETW(status.wStatus);
1061 		DPRINTF(("usbd_do_request: status = 0x%04x\n", s));
1062 		if (!(s & UES_HALT))
1063 			goto bad;
1064 		treq.bmRequestType = UT_WRITE_ENDPOINT;
1065 		treq.bRequest = UR_CLEAR_FEATURE;
1066 		USETW(treq.wValue, UF_ENDPOINT_HALT);
1067 		USETW(treq.wIndex, 0);
1068 		USETW(treq.wLength, 0);
1069 		usbd_setup_default_xfer(xfer, dev, 0, USBD_DEFAULT_TIMEOUT,
1070 					   &treq, &status, 0, 0, 0);
1071 		nerr = usbd_sync_transfer(xfer);
1072 		if (nerr)
1073 			goto bad;
1074 	}
1075 
1076  bad:
1077 	if (err) {
1078 		DPRINTF(("%s: returning err=%s\n", __func__, usbd_errstr(err)));
1079 	}
1080 	usbd_free_xfer(xfer);
1081 	return (err);
1082 }
1083 
1084 void
1085 usbd_do_request_async_cb(usbd_xfer_handle xfer,
1086     usbd_private_handle priv, usbd_status status)
1087 {
1088 #if defined(USB_DEBUG) || defined(DIAGNOSTIC)
1089 	if (xfer->actlen > xfer->length) {
1090 		DPRINTF(("usbd_do_request: overrun addr=%d type=0x%02x req=0x"
1091 			 "%02x val=%d index=%d rlen=%d length=%d actlen=%d\n",
1092 			 xfer->pipe->device->address,
1093 			 xfer->request.bmRequestType,
1094 			 xfer->request.bRequest, UGETW(xfer->request.wValue),
1095 			 UGETW(xfer->request.wIndex),
1096 			 UGETW(xfer->request.wLength),
1097 			 xfer->length, xfer->actlen));
1098 	}
1099 #endif
1100 	usbd_free_xfer(xfer);
1101 }
1102 
1103 /*
1104  * Execute a request without waiting for completion.
1105  * Can be used from interrupt context.
1106  */
1107 usbd_status
1108 usbd_do_request_async(usbd_device_handle dev, usb_device_request_t *req,
1109 		      void *data)
1110 {
1111 	usbd_xfer_handle xfer;
1112 	usbd_status err;
1113 
1114 	xfer = usbd_alloc_xfer(dev);
1115 	if (xfer == NULL)
1116 		return (USBD_NOMEM);
1117 	usbd_setup_default_xfer(xfer, dev, 0, USBD_DEFAULT_TIMEOUT, req,
1118 	    data, UGETW(req->wLength), 0, usbd_do_request_async_cb);
1119 	err = usbd_transfer(xfer);
1120 	if (err != USBD_IN_PROGRESS) {
1121 		usbd_free_xfer(xfer);
1122 		return (err);
1123 	}
1124 	return (USBD_NORMAL_COMPLETION);
1125 }
1126 
1127 const struct usbd_quirks *
1128 usbd_get_quirks(usbd_device_handle dev)
1129 {
1130 #ifdef DIAGNOSTIC
1131 	if (dev == NULL) {
1132 		printf("usbd_get_quirks: dev == NULL\n");
1133 		return 0;
1134 	}
1135 #endif
1136 	return (dev->quirks);
1137 }
1138 
1139 /* XXX do periodic free() of free list */
1140 
1141 /*
1142  * Called from keyboard driver when in polling mode.
1143  */
1144 void
1145 usbd_dopoll(usbd_interface_handle iface)
1146 {
1147 	iface->device->bus->methods->do_poll(iface->device->bus);
1148 }
1149 
1150 /*
1151  * XXX use this more???  use_polling it touched manually all over
1152  */
1153 void
1154 usbd_set_polling(usbd_device_handle dev, int on)
1155 {
1156 	if (on)
1157 		dev->bus->use_polling++;
1158 	else
1159 		dev->bus->use_polling--;
1160 
1161 	/* Kick the host controller when switching modes */
1162 	if (dev->bus->lock)
1163 		mutex_enter(dev->bus->lock);
1164 	(*dev->bus->methods->soft_intr)(dev->bus);
1165 	if (dev->bus->lock)
1166 		mutex_exit(dev->bus->lock);
1167 
1168 }
1169 
1170 
1171 usb_endpoint_descriptor_t *
1172 usbd_get_endpoint_descriptor(usbd_interface_handle iface, u_int8_t address)
1173 {
1174 	struct usbd_endpoint *ep;
1175 	int i;
1176 
1177 	for (i = 0; i < iface->idesc->bNumEndpoints; i++) {
1178 		ep = &iface->endpoints[i];
1179 		if (ep->edesc->bEndpointAddress == address)
1180 			return (iface->endpoints[i].edesc);
1181 	}
1182 	return (0);
1183 }
1184 
1185 /*
1186  * usbd_ratecheck() can limit the number of error messages that occurs.
1187  * When a device is unplugged it may take up to 0.25s for the hub driver
1188  * to notice it.  If the driver continuosly tries to do I/O operations
1189  * this can generate a large number of messages.
1190  */
1191 int
1192 usbd_ratecheck(struct timeval *last)
1193 {
1194 	static struct timeval errinterval = { 0, 250000 }; /* 0.25 s*/
1195 
1196 	return (ratecheck(last, &errinterval));
1197 }
1198 
1199 /*
1200  * Search for a vendor/product pair in an array.  The item size is
1201  * given as an argument.
1202  */
1203 const struct usb_devno *
1204 usb_match_device(const struct usb_devno *tbl, u_int nentries, u_int sz,
1205 		 u_int16_t vendor, u_int16_t product)
1206 {
1207 	while (nentries-- > 0) {
1208 		u_int16_t tproduct = tbl->ud_product;
1209 		if (tbl->ud_vendor == vendor &&
1210 		    (tproduct == product || tproduct == USB_PRODUCT_ANY))
1211 			return (tbl);
1212 		tbl = (const struct usb_devno *)((const char *)tbl + sz);
1213 	}
1214 	return (NULL);
1215 }
1216 
1217 
1218 void
1219 usb_desc_iter_init(usbd_device_handle dev, usbd_desc_iter_t *iter)
1220 {
1221 	const usb_config_descriptor_t *cd = usbd_get_config_descriptor(dev);
1222 
1223         iter->cur = (const uByte *)cd;
1224         iter->end = (const uByte *)cd + UGETW(cd->wTotalLength);
1225 }
1226 
1227 const usb_descriptor_t *
1228 usb_desc_iter_next(usbd_desc_iter_t *iter)
1229 {
1230 	const usb_descriptor_t *desc;
1231 
1232 	if (iter->cur + sizeof(usb_descriptor_t) >= iter->end) {
1233 		if (iter->cur != iter->end)
1234 			printf("usb_desc_iter_next: bad descriptor\n");
1235 		return NULL;
1236 	}
1237 	desc = (const usb_descriptor_t *)iter->cur;
1238 	if (desc->bLength == 0) {
1239 		printf("usb_desc_iter_next: descriptor length = 0\n");
1240 		return NULL;
1241 	}
1242 	iter->cur += desc->bLength;
1243 	if (iter->cur > iter->end) {
1244 		printf("usb_desc_iter_next: descriptor length too large\n");
1245 		return NULL;
1246 	}
1247 	return desc;
1248 }
1249 
1250 usbd_status
1251 usbd_get_string(usbd_device_handle dev, int si, char *buf)
1252 {
1253 	return usbd_get_string0(dev, si, buf, 1);
1254 }
1255 
1256 usbd_status
1257 usbd_get_string0(usbd_device_handle dev, int si, char *buf, int unicode)
1258 {
1259 	int swap = dev->quirks->uq_flags & UQ_SWAP_UNICODE;
1260 	usb_string_descriptor_t us;
1261 	char *s;
1262 	int i, n;
1263 	u_int16_t c;
1264 	usbd_status err;
1265 	int size;
1266 
1267 	buf[0] = '\0';
1268 	if (si == 0)
1269 		return (USBD_INVAL);
1270 	if (dev->quirks->uq_flags & UQ_NO_STRINGS)
1271 		return (USBD_STALLED);
1272 	if (dev->langid == USBD_NOLANG) {
1273 		/* Set up default language */
1274 		err = usbd_get_string_desc(dev, USB_LANGUAGE_TABLE, 0, &us,
1275 		    &size);
1276 		if (err || size < 4) {
1277 			DPRINTFN(-1,("usbd_get_string: getting lang failed, using 0\n"));
1278 			dev->langid = 0; /* Well, just pick something then */
1279 		} else {
1280 			/* Pick the first language as the default. */
1281 			dev->langid = UGETW(us.bString[0]);
1282 		}
1283 	}
1284 	err = usbd_get_string_desc(dev, si, dev->langid, &us, &size);
1285 	if (err)
1286 		return (err);
1287 	s = buf;
1288 	n = size / 2 - 1;
1289 	if (unicode) {
1290 		for (i = 0; i < n; i++) {
1291 			c = UGETW(us.bString[i]);
1292 			if (swap)
1293 				c = (c >> 8) | (c << 8);
1294 			s += wput_utf8(s, 3, c);
1295 		}
1296 		*s++ = 0;
1297 	}
1298 #ifdef COMPAT_30
1299 	else {
1300 		for (i = 0; i < n; i++) {
1301 			c = UGETW(us.bString[i]);
1302 			if (swap)
1303 				c = (c >> 8) | (c << 8);
1304 			*s++ = (c < 0x80) ? c : '?';
1305 		}
1306 		*s++ = 0;
1307 	}
1308 #endif
1309 	return (USBD_NORMAL_COMPLETION);
1310 }
1311