xref: /netbsd-src/sys/dev/usb/usbdi.c (revision 7788a0781fe6ff2cce37368b4578a7ade0850cb1)
1 /*	$NetBSD: usbdi.c,v 1.154 2013/07/11 19:46:44 aymeric 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 1.154 2013/07/11 19:46:44 aymeric 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) || defined(OHCI_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 			pipe->methods->abort(xfer);
341 			break;
342 		}
343 	}
344 	usbd_unlock_pipe(pipe);
345 	return (xfer->status);
346 }
347 
348 /* Like usbd_transfer(), but waits for completion. */
349 usbd_status
350 usbd_sync_transfer(usbd_xfer_handle xfer)
351 {
352 	xfer->flags |= USBD_SYNCHRONOUS;
353 	return (usbd_transfer(xfer));
354 }
355 
356 /* Like usbd_transfer(), but waits for completion and listens for signals. */
357 usbd_status
358 usbd_sync_transfer_sig(usbd_xfer_handle xfer)
359 {
360 	xfer->flags |= USBD_SYNCHRONOUS | USBD_SYNCHRONOUS_SIG;
361 	return (usbd_transfer(xfer));
362 }
363 
364 void *
365 usbd_alloc_buffer(usbd_xfer_handle xfer, u_int32_t size)
366 {
367 	struct usbd_bus *bus = xfer->device->bus;
368 	usbd_status err;
369 
370 #ifdef DIAGNOSTIC
371 	if (xfer->rqflags & (URQ_DEV_DMABUF | URQ_AUTO_DMABUF))
372 		printf("usbd_alloc_buffer: xfer already has a buffer\n");
373 #endif
374 	err = bus->methods->allocm(bus, &xfer->dmabuf, size);
375 	if (err)
376 		return (NULL);
377 	xfer->rqflags |= URQ_DEV_DMABUF;
378 	return (KERNADDR(&xfer->dmabuf, 0));
379 }
380 
381 void
382 usbd_free_buffer(usbd_xfer_handle xfer)
383 {
384 #ifdef DIAGNOSTIC
385 	if (!(xfer->rqflags & (URQ_DEV_DMABUF | URQ_AUTO_DMABUF))) {
386 		printf("usbd_free_buffer: no buffer\n");
387 		return;
388 	}
389 #endif
390 	xfer->rqflags &= ~(URQ_DEV_DMABUF | URQ_AUTO_DMABUF);
391 	xfer->device->bus->methods->freem(xfer->device->bus, &xfer->dmabuf);
392 }
393 
394 void *
395 usbd_get_buffer(usbd_xfer_handle xfer)
396 {
397 	if (!(xfer->rqflags & URQ_DEV_DMABUF))
398 		return (NULL);
399 	return (KERNADDR(&xfer->dmabuf, 0));
400 }
401 
402 usbd_xfer_handle
403 usbd_alloc_xfer(usbd_device_handle dev)
404 {
405 	usbd_xfer_handle xfer;
406 
407 	xfer = dev->bus->methods->allocx(dev->bus);
408 	if (xfer == NULL)
409 		return (NULL);
410 	xfer->device = dev;
411 	callout_init(&xfer->timeout_handle,
412 	    dev->bus->methods->get_lock ? CALLOUT_MPSAFE : 0);
413 	cv_init(&xfer->cv, "usbxfer");
414 	cv_init(&xfer->hccv, "usbhcxfer");
415 	DPRINTFN(5,("usbd_alloc_xfer() = %p\n", xfer));
416 	return (xfer);
417 }
418 
419 usbd_status
420 usbd_free_xfer(usbd_xfer_handle xfer)
421 {
422 	DPRINTFN(5,("usbd_free_xfer: %p\n", xfer));
423 	if (xfer->rqflags & (URQ_DEV_DMABUF | URQ_AUTO_DMABUF))
424 		usbd_free_buffer(xfer);
425 #if defined(DIAGNOSTIC)
426 	if (callout_pending(&xfer->timeout_handle)) {
427 		callout_stop(&xfer->timeout_handle);
428 		printf("usbd_free_xfer: timeout_handle pending\n");
429 	}
430 #endif
431 	cv_destroy(&xfer->cv);
432 	cv_destroy(&xfer->hccv);
433 	xfer->device->bus->methods->freex(xfer->device->bus, xfer);
434 	return (USBD_NORMAL_COMPLETION);
435 }
436 
437 void
438 usbd_setup_xfer(usbd_xfer_handle xfer, usbd_pipe_handle pipe,
439 		usbd_private_handle priv, void *buffer, u_int32_t length,
440 		u_int16_t flags, u_int32_t timeout,
441 		usbd_callback callback)
442 {
443 	xfer->pipe = pipe;
444 	xfer->priv = priv;
445 	xfer->buffer = buffer;
446 	xfer->length = length;
447 	xfer->actlen = 0;
448 	xfer->flags = flags;
449 	xfer->timeout = timeout;
450 	xfer->status = USBD_NOT_STARTED;
451 	xfer->callback = callback;
452 	xfer->rqflags &= ~URQ_REQUEST;
453 	xfer->nframes = 0;
454 }
455 
456 void
457 usbd_setup_default_xfer(usbd_xfer_handle xfer, usbd_device_handle dev,
458 			usbd_private_handle priv, u_int32_t timeout,
459 			usb_device_request_t *req, void *buffer,
460 			u_int32_t length, u_int16_t flags,
461 			usbd_callback callback)
462 {
463 	xfer->pipe = dev->default_pipe;
464 	xfer->priv = priv;
465 	xfer->buffer = buffer;
466 	xfer->length = length;
467 	xfer->actlen = 0;
468 	xfer->flags = flags;
469 	xfer->timeout = timeout;
470 	xfer->status = USBD_NOT_STARTED;
471 	xfer->callback = callback;
472 	xfer->request = *req;
473 	xfer->rqflags |= URQ_REQUEST;
474 	xfer->nframes = 0;
475 }
476 
477 void
478 usbd_setup_isoc_xfer(usbd_xfer_handle xfer, usbd_pipe_handle pipe,
479 		     usbd_private_handle priv, u_int16_t *frlengths,
480 		     u_int32_t nframes, u_int16_t flags, usbd_callback callback)
481 {
482 	xfer->pipe = pipe;
483 	xfer->priv = priv;
484 	xfer->buffer = 0;
485 	xfer->length = 0;
486 	xfer->actlen = 0;
487 	xfer->flags = flags;
488 	xfer->timeout = USBD_NO_TIMEOUT;
489 	xfer->status = USBD_NOT_STARTED;
490 	xfer->callback = callback;
491 	xfer->rqflags &= ~URQ_REQUEST;
492 	xfer->frlengths = frlengths;
493 	xfer->nframes = nframes;
494 }
495 
496 void
497 usbd_get_xfer_status(usbd_xfer_handle xfer, usbd_private_handle *priv,
498 		     void **buffer, u_int32_t *count, usbd_status *status)
499 {
500 	if (priv != NULL)
501 		*priv = xfer->priv;
502 	if (buffer != NULL)
503 		*buffer = xfer->buffer;
504 	if (count != NULL)
505 		*count = xfer->actlen;
506 	if (status != NULL)
507 		*status = xfer->status;
508 }
509 
510 usb_config_descriptor_t *
511 usbd_get_config_descriptor(usbd_device_handle dev)
512 {
513 #ifdef DIAGNOSTIC
514 	if (dev == NULL) {
515 		printf("usbd_get_config_descriptor: dev == NULL\n");
516 		return (NULL);
517 	}
518 #endif
519 	return (dev->cdesc);
520 }
521 
522 usb_interface_descriptor_t *
523 usbd_get_interface_descriptor(usbd_interface_handle iface)
524 {
525 #ifdef DIAGNOSTIC
526 	if (iface == NULL) {
527 		printf("usbd_get_interface_descriptor: dev == NULL\n");
528 		return (NULL);
529 	}
530 #endif
531 	return (iface->idesc);
532 }
533 
534 usb_device_descriptor_t *
535 usbd_get_device_descriptor(usbd_device_handle dev)
536 {
537 	return (&dev->ddesc);
538 }
539 
540 usb_endpoint_descriptor_t *
541 usbd_interface2endpoint_descriptor(usbd_interface_handle iface, u_int8_t index)
542 {
543 	if (index >= iface->idesc->bNumEndpoints)
544 		return (NULL);
545 	return (iface->endpoints[index].edesc);
546 }
547 
548 /* Some drivers may wish to abort requests on the default pipe, *
549  * but there is no mechanism for getting a handle on it.        */
550 usbd_status
551 usbd_abort_default_pipe(struct usbd_device *device)
552 {
553 
554 	return usbd_abort_pipe(device->default_pipe);
555 }
556 
557 usbd_status
558 usbd_abort_pipe(usbd_pipe_handle pipe)
559 {
560 	usbd_status err;
561 	int s;
562 	usbd_xfer_handle intrxfer = pipe->intrxfer;
563 
564 #ifdef DIAGNOSTIC
565 	if (pipe == NULL) {
566 		printf("usbd_abort_pipe: pipe==NULL\n");
567 		return (USBD_NORMAL_COMPLETION);
568 	}
569 #endif
570 	usbd_lock_pipe(pipe);
571 	err = usbd_ar_pipe(pipe);
572 	usbd_unlock_pipe(pipe);
573 	if (pipe->intrxfer != intrxfer)
574 		usbd_free_xfer(intrxfer);
575 	return (err);
576 }
577 
578 usbd_status
579 usbd_clear_endpoint_stall(usbd_pipe_handle pipe)
580 {
581 	usbd_device_handle dev = pipe->device;
582 	usb_device_request_t req;
583 	usbd_status err;
584 
585 	DPRINTFN(8, ("usbd_clear_endpoint_stall\n"));
586 
587 	/*
588 	 * Clearing en endpoint stall resets the endpoint toggle, so
589 	 * do the same to the HC toggle.
590 	 */
591 	pipe->methods->cleartoggle(pipe);
592 
593 	req.bmRequestType = UT_WRITE_ENDPOINT;
594 	req.bRequest = UR_CLEAR_FEATURE;
595 	USETW(req.wValue, UF_ENDPOINT_HALT);
596 	USETW(req.wIndex, pipe->endpoint->edesc->bEndpointAddress);
597 	USETW(req.wLength, 0);
598 	err = usbd_do_request(dev, &req, 0);
599 #if 0
600 XXX should we do this?
601 	if (!err) {
602 		pipe->state = USBD_PIPE_ACTIVE;
603 		/* XXX activate pipe */
604 	}
605 #endif
606 	return (err);
607 }
608 
609 void
610 usbd_clear_endpoint_stall_async_cb(void *arg)
611 {
612 	usbd_pipe_handle pipe = arg;
613 	usbd_device_handle dev = pipe->device;
614 	usb_device_request_t req;
615 
616 	pipe->methods->cleartoggle(pipe);
617 
618 	req.bmRequestType = UT_WRITE_ENDPOINT;
619 	req.bRequest = UR_CLEAR_FEATURE;
620 	USETW(req.wValue, UF_ENDPOINT_HALT);
621 	USETW(req.wIndex, pipe->endpoint->edesc->bEndpointAddress);
622 	USETW(req.wLength, 0);
623 	(void)usbd_do_request_async(dev, &req, 0);
624 }
625 
626 void
627 usbd_clear_endpoint_stall_async(usbd_pipe_handle pipe)
628 {
629 
630 	usb_add_task(pipe->device, &pipe->async_task, USB_TASKQ_DRIVER);
631 }
632 
633 void
634 usbd_clear_endpoint_toggle(usbd_pipe_handle pipe)
635 {
636 	pipe->methods->cleartoggle(pipe);
637 }
638 
639 usbd_status
640 usbd_endpoint_count(usbd_interface_handle iface, u_int8_t *count)
641 {
642 #ifdef DIAGNOSTIC
643 	if (iface == NULL || iface->idesc == NULL) {
644 		printf("usbd_endpoint_count: NULL pointer\n");
645 		return (USBD_INVAL);
646 	}
647 #endif
648 	*count = iface->idesc->bNumEndpoints;
649 	return (USBD_NORMAL_COMPLETION);
650 }
651 
652 usbd_status
653 usbd_interface_count(usbd_device_handle dev, u_int8_t *count)
654 {
655 	if (dev->cdesc == NULL)
656 		return (USBD_NOT_CONFIGURED);
657 	*count = dev->cdesc->bNumInterface;
658 	return (USBD_NORMAL_COMPLETION);
659 }
660 
661 void
662 usbd_interface2device_handle(usbd_interface_handle iface,
663 			     usbd_device_handle *dev)
664 {
665 	*dev = iface->device;
666 }
667 
668 usbd_status
669 usbd_device2interface_handle(usbd_device_handle dev,
670 			     u_int8_t ifaceno, usbd_interface_handle *iface)
671 {
672 	if (dev->cdesc == NULL)
673 		return (USBD_NOT_CONFIGURED);
674 	if (ifaceno >= dev->cdesc->bNumInterface)
675 		return (USBD_INVAL);
676 	*iface = &dev->ifaces[ifaceno];
677 	return (USBD_NORMAL_COMPLETION);
678 }
679 
680 usbd_device_handle
681 usbd_pipe2device_handle(usbd_pipe_handle pipe)
682 {
683 	return (pipe->device);
684 }
685 
686 /* XXXX use altno */
687 usbd_status
688 usbd_set_interface(usbd_interface_handle iface, int altidx)
689 {
690 	usb_device_request_t req;
691 	usbd_status err;
692 	void *endpoints;
693 
694 	if (LIST_FIRST(&iface->pipes) != 0)
695 		return (USBD_IN_USE);
696 
697 	endpoints = iface->endpoints;
698 	err = usbd_fill_iface_data(iface->device, iface->index, altidx);
699 	if (err)
700 		return (err);
701 
702 	/* new setting works, we can free old endpoints */
703 	if (endpoints != NULL)
704 		free(endpoints, M_USB);
705 
706 #ifdef DIAGNOSTIC
707 	if (iface->idesc == NULL) {
708 		printf("usbd_set_interface: NULL pointer\n");
709 		return (USBD_INVAL);
710 	}
711 #endif
712 
713 	req.bmRequestType = UT_WRITE_INTERFACE;
714 	req.bRequest = UR_SET_INTERFACE;
715 	USETW(req.wValue, iface->idesc->bAlternateSetting);
716 	USETW(req.wIndex, iface->idesc->bInterfaceNumber);
717 	USETW(req.wLength, 0);
718 	return (usbd_do_request(iface->device, &req, 0));
719 }
720 
721 int
722 usbd_get_no_alts(usb_config_descriptor_t *cdesc, int ifaceno)
723 {
724 	char *p = (char *)cdesc;
725 	char *end = p + UGETW(cdesc->wTotalLength);
726 	usb_interface_descriptor_t *d;
727 	int n;
728 
729 	for (n = 0; p < end; p += d->bLength) {
730 		d = (usb_interface_descriptor_t *)p;
731 		if (p + d->bLength <= end &&
732 		    d->bDescriptorType == UDESC_INTERFACE &&
733 		    d->bInterfaceNumber == ifaceno)
734 			n++;
735 	}
736 	return (n);
737 }
738 
739 int
740 usbd_get_interface_altindex(usbd_interface_handle iface)
741 {
742 	return (iface->altindex);
743 }
744 
745 usbd_status
746 usbd_get_interface(usbd_interface_handle iface, u_int8_t *aiface)
747 {
748 	usb_device_request_t req;
749 
750 	req.bmRequestType = UT_READ_INTERFACE;
751 	req.bRequest = UR_GET_INTERFACE;
752 	USETW(req.wValue, 0);
753 	USETW(req.wIndex, iface->idesc->bInterfaceNumber);
754 	USETW(req.wLength, 1);
755 	return (usbd_do_request(iface->device, &req, aiface));
756 }
757 
758 /*** Internal routines ***/
759 
760 /* Dequeue all pipe operations, called at splusb(). */
761 Static usbd_status
762 usbd_ar_pipe(usbd_pipe_handle pipe)
763 {
764 	usbd_xfer_handle xfer;
765 
766 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
767 
768 	DPRINTFN(2,("usbd_ar_pipe: pipe=%p\n", pipe));
769 #ifdef USB_DEBUG
770 	if (usbdebug > 5)
771 		usbd_dump_queue(pipe);
772 #endif
773 	pipe->repeat = 0;
774 	pipe->aborting = 1;
775 	while ((xfer = SIMPLEQ_FIRST(&pipe->queue)) != NULL) {
776 		DPRINTFN(2,("usbd_ar_pipe: pipe=%p xfer=%p (methods=%p)\n",
777 			    pipe, xfer, pipe->methods));
778 		/* Make the HC abort it (and invoke the callback). */
779 		pipe->methods->abort(xfer);
780 		/* XXX only for non-0 usbd_clear_endpoint_stall(pipe); */
781 	}
782 	pipe->aborting = 0;
783 	return (USBD_NORMAL_COMPLETION);
784 }
785 
786 /* Called with USB lock held. */
787 void
788 usb_transfer_complete(usbd_xfer_handle xfer)
789 {
790 	usbd_pipe_handle pipe = xfer->pipe;
791 	usb_dma_t *dmap = &xfer->dmabuf;
792 	int sync = xfer->flags & USBD_SYNCHRONOUS;
793 	int erred = xfer->status == USBD_CANCELLED ||
794 	    xfer->status == USBD_TIMEOUT;
795 	int polling = pipe->device->bus->use_polling;
796 	int repeat;
797 
798 	DPRINTFN(5, ("usb_transfer_complete: pipe=%p xfer=%p status=%d "
799 		     "actlen=%d\n", pipe, xfer, xfer->status, xfer->actlen));
800 
801 	KASSERT(polling || pipe->device->bus->lock == NULL ||
802 	    mutex_owned(pipe->device->bus->lock));
803 
804 #ifdef DIAGNOSTIC
805 	if (xfer->busy_free != XFER_ONQU) {
806 		printf("usb_transfer_complete: xfer=%p not queued 0x%08x\n",
807 		       xfer, xfer->busy_free);
808 	}
809 #endif
810 
811 #ifdef DIAGNOSTIC
812 	if (pipe == NULL) {
813 		printf("usb_transfer_complete: pipe==0, xfer=%p\n", xfer);
814 		return;
815 	}
816 #endif
817 	repeat = pipe->repeat;
818 	/* XXXX */
819 	if (polling)
820 		pipe->running = 0;
821 
822 	if (!(xfer->flags & USBD_NO_COPY) && xfer->actlen != 0 &&
823 	    usbd_xfer_isread(xfer)) {
824 #ifdef DIAGNOSTIC
825 		if (xfer->actlen > xfer->length) {
826 			printf("%s: actlen (%d) > len (%d)\n", __func__,
827 			       xfer->actlen, xfer->length);
828 			xfer->actlen = xfer->length;
829 		}
830 #endif
831 		memcpy(xfer->buffer, KERNADDR(dmap, 0), xfer->actlen);
832 	}
833 
834 	/* if we allocated the buffer in usbd_transfer() we free it here. */
835 	if (xfer->rqflags & URQ_AUTO_DMABUF) {
836 		if (!repeat) {
837 			struct usbd_bus *bus = pipe->device->bus;
838 			bus->methods->freem(bus, dmap);
839 			xfer->rqflags &= ~URQ_AUTO_DMABUF;
840 		}
841 	}
842 
843 	if (!repeat) {
844 		/* Remove request from queue. */
845 
846 		KASSERTMSG(!SIMPLEQ_EMPTY(&pipe->queue),
847 		    "pipe %p is empty, but xfer %p wants to complete", pipe,
848 		     xfer);
849 #ifdef DIAGNOSTIC
850 		if (xfer != SIMPLEQ_FIRST(&pipe->queue))
851 			printf("%s: bad dequeue %p != %p\n", __func__,
852 			       xfer, SIMPLEQ_FIRST(&pipe->queue));
853 		xfer->busy_free = XFER_BUSY;
854 #endif
855 		SIMPLEQ_REMOVE_HEAD(&pipe->queue, next);
856 	}
857 	DPRINTFN(5,("usb_transfer_complete: repeat=%d new head=%p\n",
858 		    repeat, SIMPLEQ_FIRST(&pipe->queue)));
859 
860 	/* Count completed transfers. */
861 	++pipe->device->bus->stats.uds_requests
862 		[pipe->endpoint->edesc->bmAttributes & UE_XFERTYPE];
863 
864 	xfer->done = 1;
865 	if (!xfer->status && xfer->actlen < xfer->length &&
866 	    !(xfer->flags & USBD_SHORT_XFER_OK)) {
867 		DPRINTFN(-1,("usb_transfer_complete: short transfer %d<%d\n",
868 			     xfer->actlen, xfer->length));
869 		xfer->status = USBD_SHORT_XFER;
870 	}
871 
872 	if (repeat) {
873 		if (xfer->callback) {
874 			if (pipe->device->bus->lock && !polling)
875 				mutex_exit(pipe->device->bus->lock);
876 
877 			if (!(pipe->flags & USBD_MPSAFE))
878 				KERNEL_LOCK(1, curlwp);
879 			xfer->callback(xfer, xfer->priv, xfer->status);
880 			if (!(pipe->flags & USBD_MPSAFE))
881 				KERNEL_UNLOCK_ONE(curlwp);
882 
883 			if (pipe->device->bus->lock && !polling)
884 				mutex_enter(pipe->device->bus->lock);
885 		}
886 		pipe->methods->done(xfer);
887 	} else {
888 		pipe->methods->done(xfer);
889 		if (xfer->callback) {
890 			if (pipe->device->bus->lock && !polling)
891 				mutex_exit(pipe->device->bus->lock);
892 
893 			if (!(pipe->flags & USBD_MPSAFE))
894 				KERNEL_LOCK(1, curlwp);
895 			xfer->callback(xfer, xfer->priv, xfer->status);
896 			if (!(pipe->flags & USBD_MPSAFE))
897 				KERNEL_UNLOCK_ONE(curlwp);
898 
899 			if (pipe->device->bus->lock && !polling)
900 				mutex_enter(pipe->device->bus->lock);
901 		}
902 	}
903 
904 	if (sync && !polling) {
905 		if (pipe->device->bus->lock)
906 			cv_broadcast(&xfer->cv);
907 		else
908 			wakeup(xfer);	/* XXXSMP ok */
909 	}
910 
911 	if (!repeat) {
912 		/* XXX should we stop the queue on all errors? */
913 		if (erred && pipe->iface != NULL)	/* not control pipe */
914 			pipe->running = 0;
915 		else
916 			usbd_start_next(pipe);
917 	}
918 }
919 
920 /* Called with USB lock held. */
921 usbd_status
922 usb_insert_transfer(usbd_xfer_handle xfer)
923 {
924 	usbd_pipe_handle pipe = xfer->pipe;
925 	usbd_status err;
926 
927 	DPRINTFN(5,("usb_insert_transfer: pipe=%p running=%d timeout=%d\n",
928 		    pipe, pipe->running, xfer->timeout));
929 
930 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
931 
932 #ifdef DIAGNOSTIC
933 	if (xfer->busy_free != XFER_BUSY) {
934 		printf("usb_insert_transfer: xfer=%p not busy 0x%08x\n",
935 		       xfer, xfer->busy_free);
936 		return (USBD_INVAL);
937 	}
938 	xfer->busy_free = XFER_ONQU;
939 #endif
940 	SIMPLEQ_INSERT_TAIL(&pipe->queue, xfer, next);
941 	if (pipe->running)
942 		err = USBD_IN_PROGRESS;
943 	else {
944 		pipe->running = 1;
945 		err = USBD_NORMAL_COMPLETION;
946 	}
947 	return (err);
948 }
949 
950 /* Called with USB lock held. */
951 void
952 usbd_start_next(usbd_pipe_handle pipe)
953 {
954 	usbd_xfer_handle xfer;
955 	usbd_status err;
956 
957 #ifdef DIAGNOSTIC
958 	if (pipe == NULL) {
959 		printf("usbd_start_next: pipe == NULL\n");
960 		return;
961 	}
962 	if (pipe->methods == NULL || pipe->methods->start == NULL) {
963 		printf("usbd_start_next: pipe=%p no start method\n", pipe);
964 		return;
965 	}
966 #endif
967 
968 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
969 
970 	/* Get next request in queue. */
971 	xfer = SIMPLEQ_FIRST(&pipe->queue);
972 	DPRINTFN(5, ("usbd_start_next: pipe=%p, xfer=%p\n", pipe, xfer));
973 	if (xfer == NULL) {
974 		pipe->running = 0;
975 	} else {
976 		if (pipe->device->bus->lock)
977 			mutex_exit(pipe->device->bus->lock);
978 		err = pipe->methods->start(xfer);
979 		if (pipe->device->bus->lock)
980 			mutex_enter(pipe->device->bus->lock);
981 		if (err != USBD_IN_PROGRESS) {
982 			printf("usbd_start_next: error=%d\n", err);
983 			pipe->running = 0;
984 			/* XXX do what? */
985 		}
986 	}
987 
988 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
989 }
990 
991 usbd_status
992 usbd_do_request(usbd_device_handle dev, usb_device_request_t *req, void *data)
993 {
994 	return (usbd_do_request_flags(dev, req, data, 0, 0,
995 				      USBD_DEFAULT_TIMEOUT));
996 }
997 
998 usbd_status
999 usbd_do_request_flags(usbd_device_handle dev, usb_device_request_t *req,
1000 		      void *data, u_int16_t flags, int *actlen, u_int32_t timo)
1001 {
1002 	return (usbd_do_request_flags_pipe(dev, dev->default_pipe, req,
1003 					   data, flags, actlen, timo));
1004 }
1005 
1006 usbd_status
1007 usbd_do_request_flags_pipe(usbd_device_handle dev, usbd_pipe_handle pipe,
1008 	usb_device_request_t *req, void *data, u_int16_t flags, int *actlen,
1009 	u_int32_t timeout)
1010 {
1011 	usbd_xfer_handle xfer;
1012 	usbd_status err;
1013 
1014 #ifdef DIAGNOSTIC
1015 	if (cpu_intr_p() || cpu_softintr_p()) {
1016 		printf("usbd_do_request: not in process context\n");
1017 		return (USBD_INVAL);
1018 	}
1019 #endif
1020 
1021 	xfer = usbd_alloc_xfer(dev);
1022 	if (xfer == NULL)
1023 		return (USBD_NOMEM);
1024 	usbd_setup_default_xfer(xfer, dev, 0, timeout, req,
1025 				data, UGETW(req->wLength), flags, 0);
1026 	xfer->pipe = pipe;
1027 	err = usbd_sync_transfer(xfer);
1028 #if defined(USB_DEBUG) || defined(DIAGNOSTIC)
1029 	if (xfer->actlen > xfer->length) {
1030 		DPRINTF(("%s: overrun addr=%d type=0x%02x req=0x"
1031 			 "%02x val=%d index=%d rlen=%d length=%d actlen=%d\n",
1032 			 __func__, dev->address, xfer->request.bmRequestType,
1033 			 xfer->request.bRequest, UGETW(xfer->request.wValue),
1034 			 UGETW(xfer->request.wIndex),
1035 			 UGETW(xfer->request.wLength),
1036 			 xfer->length, xfer->actlen));
1037 	}
1038 #endif
1039 	if (actlen != NULL)
1040 		*actlen = xfer->actlen;
1041 	if (err == USBD_STALLED) {
1042 		/*
1043 		 * The control endpoint has stalled.  Control endpoints
1044 		 * should not halt, but some may do so anyway so clear
1045 		 * any halt condition.
1046 		 */
1047 		usb_device_request_t treq;
1048 		usb_status_t status;
1049 		u_int16_t s;
1050 		usbd_status nerr;
1051 
1052 		treq.bmRequestType = UT_READ_ENDPOINT;
1053 		treq.bRequest = UR_GET_STATUS;
1054 		USETW(treq.wValue, 0);
1055 		USETW(treq.wIndex, 0);
1056 		USETW(treq.wLength, sizeof(usb_status_t));
1057 		usbd_setup_default_xfer(xfer, dev, 0, USBD_DEFAULT_TIMEOUT,
1058 					   &treq, &status,sizeof(usb_status_t),
1059 					   0, 0);
1060 		nerr = usbd_sync_transfer(xfer);
1061 		if (nerr)
1062 			goto bad;
1063 		s = UGETW(status.wStatus);
1064 		DPRINTF(("usbd_do_request: status = 0x%04x\n", s));
1065 		if (!(s & UES_HALT))
1066 			goto bad;
1067 		treq.bmRequestType = UT_WRITE_ENDPOINT;
1068 		treq.bRequest = UR_CLEAR_FEATURE;
1069 		USETW(treq.wValue, UF_ENDPOINT_HALT);
1070 		USETW(treq.wIndex, 0);
1071 		USETW(treq.wLength, 0);
1072 		usbd_setup_default_xfer(xfer, dev, 0, USBD_DEFAULT_TIMEOUT,
1073 					   &treq, &status, 0, 0, 0);
1074 		nerr = usbd_sync_transfer(xfer);
1075 		if (nerr)
1076 			goto bad;
1077 	}
1078 
1079  bad:
1080 	if (err) {
1081 		DPRINTF(("%s: returning err=%s\n", __func__, usbd_errstr(err)));
1082 	}
1083 	usbd_free_xfer(xfer);
1084 	return (err);
1085 }
1086 
1087 void
1088 usbd_do_request_async_cb(usbd_xfer_handle xfer,
1089     usbd_private_handle priv, usbd_status status)
1090 {
1091 #if defined(USB_DEBUG) || defined(DIAGNOSTIC)
1092 	if (xfer->actlen > xfer->length) {
1093 		DPRINTF(("usbd_do_request: overrun addr=%d type=0x%02x req=0x"
1094 			 "%02x val=%d index=%d rlen=%d length=%d actlen=%d\n",
1095 			 xfer->pipe->device->address,
1096 			 xfer->request.bmRequestType,
1097 			 xfer->request.bRequest, UGETW(xfer->request.wValue),
1098 			 UGETW(xfer->request.wIndex),
1099 			 UGETW(xfer->request.wLength),
1100 			 xfer->length, xfer->actlen));
1101 	}
1102 #endif
1103 	usbd_free_xfer(xfer);
1104 }
1105 
1106 /*
1107  * Execute a request without waiting for completion.
1108  * Can be used from interrupt context.
1109  */
1110 usbd_status
1111 usbd_do_request_async(usbd_device_handle dev, usb_device_request_t *req,
1112 		      void *data)
1113 {
1114 	usbd_xfer_handle xfer;
1115 	usbd_status err;
1116 
1117 	xfer = usbd_alloc_xfer(dev);
1118 	if (xfer == NULL)
1119 		return (USBD_NOMEM);
1120 	usbd_setup_default_xfer(xfer, dev, 0, USBD_DEFAULT_TIMEOUT, req,
1121 	    data, UGETW(req->wLength), 0, usbd_do_request_async_cb);
1122 	err = usbd_transfer(xfer);
1123 	if (err != USBD_IN_PROGRESS) {
1124 		usbd_free_xfer(xfer);
1125 		return (err);
1126 	}
1127 	return (USBD_NORMAL_COMPLETION);
1128 }
1129 
1130 const struct usbd_quirks *
1131 usbd_get_quirks(usbd_device_handle dev)
1132 {
1133 #ifdef DIAGNOSTIC
1134 	if (dev == NULL) {
1135 		printf("usbd_get_quirks: dev == NULL\n");
1136 		return 0;
1137 	}
1138 #endif
1139 	return (dev->quirks);
1140 }
1141 
1142 /* XXX do periodic free() of free list */
1143 
1144 /*
1145  * Called from keyboard driver when in polling mode.
1146  */
1147 void
1148 usbd_dopoll(usbd_interface_handle iface)
1149 {
1150 	iface->device->bus->methods->do_poll(iface->device->bus);
1151 }
1152 
1153 /*
1154  * XXX use this more???  use_polling it touched manually all over
1155  */
1156 void
1157 usbd_set_polling(usbd_device_handle dev, int on)
1158 {
1159 	if (on)
1160 		dev->bus->use_polling++;
1161 	else
1162 		dev->bus->use_polling--;
1163 
1164 	/* Kick the host controller when switching modes */
1165 	if (dev->bus->lock)
1166 		mutex_enter(dev->bus->lock);
1167 	(*dev->bus->methods->soft_intr)(dev->bus);
1168 	if (dev->bus->lock)
1169 		mutex_exit(dev->bus->lock);
1170 
1171 }
1172 
1173 
1174 usb_endpoint_descriptor_t *
1175 usbd_get_endpoint_descriptor(usbd_interface_handle iface, u_int8_t address)
1176 {
1177 	struct usbd_endpoint *ep;
1178 	int i;
1179 
1180 	for (i = 0; i < iface->idesc->bNumEndpoints; i++) {
1181 		ep = &iface->endpoints[i];
1182 		if (ep->edesc->bEndpointAddress == address)
1183 			return (iface->endpoints[i].edesc);
1184 	}
1185 	return (NULL);
1186 }
1187 
1188 /*
1189  * usbd_ratecheck() can limit the number of error messages that occurs.
1190  * When a device is unplugged it may take up to 0.25s for the hub driver
1191  * to notice it.  If the driver continuosly tries to do I/O operations
1192  * this can generate a large number of messages.
1193  */
1194 int
1195 usbd_ratecheck(struct timeval *last)
1196 {
1197 	static struct timeval errinterval = { 0, 250000 }; /* 0.25 s*/
1198 
1199 	return (ratecheck(last, &errinterval));
1200 }
1201 
1202 /*
1203  * Search for a vendor/product pair in an array.  The item size is
1204  * given as an argument.
1205  */
1206 const struct usb_devno *
1207 usb_match_device(const struct usb_devno *tbl, u_int nentries, u_int sz,
1208 		 u_int16_t vendor, u_int16_t product)
1209 {
1210 	while (nentries-- > 0) {
1211 		u_int16_t tproduct = tbl->ud_product;
1212 		if (tbl->ud_vendor == vendor &&
1213 		    (tproduct == product || tproduct == USB_PRODUCT_ANY))
1214 			return (tbl);
1215 		tbl = (const struct usb_devno *)((const char *)tbl + sz);
1216 	}
1217 	return (NULL);
1218 }
1219 
1220 
1221 void
1222 usb_desc_iter_init(usbd_device_handle dev, usbd_desc_iter_t *iter)
1223 {
1224 	const usb_config_descriptor_t *cd = usbd_get_config_descriptor(dev);
1225 
1226         iter->cur = (const uByte *)cd;
1227         iter->end = (const uByte *)cd + UGETW(cd->wTotalLength);
1228 }
1229 
1230 const usb_descriptor_t *
1231 usb_desc_iter_next(usbd_desc_iter_t *iter)
1232 {
1233 	const usb_descriptor_t *desc;
1234 
1235 	if (iter->cur + sizeof(usb_descriptor_t) >= iter->end) {
1236 		if (iter->cur != iter->end)
1237 			printf("usb_desc_iter_next: bad descriptor\n");
1238 		return NULL;
1239 	}
1240 	desc = (const usb_descriptor_t *)iter->cur;
1241 	if (desc->bLength == 0) {
1242 		printf("usb_desc_iter_next: descriptor length = 0\n");
1243 		return NULL;
1244 	}
1245 	iter->cur += desc->bLength;
1246 	if (iter->cur > iter->end) {
1247 		printf("usb_desc_iter_next: descriptor length too large\n");
1248 		return NULL;
1249 	}
1250 	return desc;
1251 }
1252 
1253 usbd_status
1254 usbd_get_string(usbd_device_handle dev, int si, char *buf)
1255 {
1256 	return usbd_get_string0(dev, si, buf, 1);
1257 }
1258 
1259 usbd_status
1260 usbd_get_string0(usbd_device_handle dev, int si, char *buf, int unicode)
1261 {
1262 	int swap = dev->quirks->uq_flags & UQ_SWAP_UNICODE;
1263 	usb_string_descriptor_t us;
1264 	char *s;
1265 	int i, n;
1266 	u_int16_t c;
1267 	usbd_status err;
1268 	int size;
1269 
1270 	buf[0] = '\0';
1271 	if (si == 0)
1272 		return (USBD_INVAL);
1273 	if (dev->quirks->uq_flags & UQ_NO_STRINGS)
1274 		return (USBD_STALLED);
1275 	if (dev->langid == USBD_NOLANG) {
1276 		/* Set up default language */
1277 		err = usbd_get_string_desc(dev, USB_LANGUAGE_TABLE, 0, &us,
1278 		    &size);
1279 		if (err || size < 4) {
1280 			DPRINTFN(-1,("usbd_get_string: getting lang failed, using 0\n"));
1281 			dev->langid = 0; /* Well, just pick something then */
1282 		} else {
1283 			/* Pick the first language as the default. */
1284 			dev->langid = UGETW(us.bString[0]);
1285 		}
1286 	}
1287 	err = usbd_get_string_desc(dev, si, dev->langid, &us, &size);
1288 	if (err)
1289 		return (err);
1290 	s = buf;
1291 	n = size / 2 - 1;
1292 	if (unicode) {
1293 		for (i = 0; i < n; i++) {
1294 			c = UGETW(us.bString[i]);
1295 			if (swap)
1296 				c = (c >> 8) | (c << 8);
1297 			s += wput_utf8(s, 3, c);
1298 		}
1299 		*s++ = 0;
1300 	}
1301 #ifdef COMPAT_30
1302 	else {
1303 		for (i = 0; i < n; i++) {
1304 			c = UGETW(us.bString[i]);
1305 			if (swap)
1306 				c = (c >> 8) | (c << 8);
1307 			*s++ = (c < 0x80) ? c : '?';
1308 		}
1309 		*s++ = 0;
1310 	}
1311 #endif
1312 	return (USBD_NORMAL_COMPLETION);
1313 }
1314