xref: /netbsd-src/sys/dev/usb/usbdi.c (revision e61202360d5611414dd6f6115934a96aa1f50b1a)
1 /*	$NetBSD: usbdi.c,v 1.139 2012/07/15 21:13:31 mrg 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 1.139 2012/07/15 21:13:31 mrg Exp $");
35 
36 #include "opt_compat_netbsd.h"
37 #include "opt_usb.h"
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/kernel.h>
42 #include <sys/device.h>
43 #include <sys/malloc.h>
44 #include <sys/proc.h>
45 #include <sys/bus.h>
46 #include <sys/cpu.h>
47 
48 #include <dev/usb/usb.h>
49 #include <dev/usb/usbdi.h>
50 #include <dev/usb/usbdi_util.h>
51 #include <dev/usb/usbdivar.h>
52 #include <dev/usb/usb_mem.h>
53 #include <dev/usb/usb_quirks.h>
54 
55 /* UTF-8 encoding stuff */
56 #include <fs/unicode.h>
57 
58 #ifdef USB_DEBUG
59 #define DPRINTF(x)	if (usbdebug) printf x
60 #define DPRINTFN(n,x)	if (usbdebug>(n)) printf x
61 extern int usbdebug;
62 #else
63 #define DPRINTF(x)
64 #define DPRINTFN(n,x)
65 #endif
66 
67 Static usbd_status usbd_ar_pipe(usbd_pipe_handle pipe);
68 Static void usbd_do_request_async_cb
69 	(usbd_xfer_handle, usbd_private_handle, usbd_status);
70 Static void usbd_start_next(usbd_pipe_handle pipe);
71 Static usbd_status usbd_open_pipe_ival
72 	(usbd_interface_handle, u_int8_t, u_int8_t, usbd_pipe_handle *, int);
73 
74 static inline int
75 usbd_xfer_isread(usbd_xfer_handle xfer)
76 {
77 	if (xfer->rqflags & URQ_REQUEST)
78 		return (xfer->request.bmRequestType & UT_READ);
79 	else
80 		return (xfer->pipe->endpoint->edesc->bEndpointAddress &
81 			UE_DIR_IN);
82 }
83 
84 #if defined(USB_DEBUG) || defined(EHCI_DEBUG)
85 void
86 usbd_dump_iface(struct usbd_interface *iface)
87 {
88 	printf("usbd_dump_iface: iface=%p\n", iface);
89 	if (iface == NULL)
90 		return;
91 	printf(" device=%p idesc=%p index=%d altindex=%d priv=%p\n",
92 	       iface->device, iface->idesc, iface->index, iface->altindex,
93 	       iface->priv);
94 }
95 
96 void
97 usbd_dump_device(struct usbd_device *dev)
98 {
99 	printf("usbd_dump_device: dev=%p\n", dev);
100 	if (dev == NULL)
101 		return;
102 	printf(" bus=%p default_pipe=%p\n", dev->bus, dev->default_pipe);
103 	printf(" address=%d config=%d depth=%d speed=%d self_powered=%d "
104 	       "power=%d langid=%d\n",
105 	       dev->address, dev->config, dev->depth, dev->speed,
106 	       dev->self_powered, dev->power, dev->langid);
107 }
108 
109 void
110 usbd_dump_endpoint(struct usbd_endpoint *endp)
111 {
112 	printf("usbd_dump_endpoint: endp=%p\n", endp);
113 	if (endp == NULL)
114 		return;
115 	printf(" edesc=%p refcnt=%d\n", endp->edesc, endp->refcnt);
116 	if (endp->edesc)
117 		printf(" bEndpointAddress=0x%02x\n",
118 		       endp->edesc->bEndpointAddress);
119 }
120 
121 void
122 usbd_dump_queue(usbd_pipe_handle pipe)
123 {
124 	usbd_xfer_handle xfer;
125 
126 	printf("usbd_dump_queue: pipe=%p\n", pipe);
127 	SIMPLEQ_FOREACH(xfer, &pipe->queue, next) {
128 		printf("  xfer=%p\n", xfer);
129 	}
130 }
131 
132 void
133 usbd_dump_pipe(usbd_pipe_handle pipe)
134 {
135 	printf("usbd_dump_pipe: pipe=%p\n", pipe);
136 	if (pipe == NULL)
137 		return;
138 	usbd_dump_iface(pipe->iface);
139 	usbd_dump_device(pipe->device);
140 	usbd_dump_endpoint(pipe->endpoint);
141 	printf(" (usbd_dump_pipe:)\n refcnt=%d running=%d aborting=%d\n",
142 	       pipe->refcnt, pipe->running, pipe->aborting);
143 	printf(" intrxfer=%p, repeat=%d, interval=%d\n",
144 	       pipe->intrxfer, pipe->repeat, pipe->interval);
145 }
146 #endif
147 
148 usbd_status
149 usbd_open_pipe(usbd_interface_handle iface, u_int8_t address,
150 	       u_int8_t flags, usbd_pipe_handle *pipe)
151 {
152 	return (usbd_open_pipe_ival(iface, address, flags, pipe,
153 				    USBD_DEFAULT_INTERVAL));
154 }
155 
156 usbd_status
157 usbd_open_pipe_ival(usbd_interface_handle iface, u_int8_t address,
158 		    u_int8_t flags, usbd_pipe_handle *pipe, int ival)
159 {
160 	usbd_pipe_handle p;
161 	struct usbd_endpoint *ep;
162 	usbd_status err;
163 	int i;
164 
165 	DPRINTFN(3,("usbd_open_pipe: iface=%p address=0x%x flags=0x%x\n",
166 		    iface, address, flags));
167 
168 	for (i = 0; i < iface->idesc->bNumEndpoints; i++) {
169 		ep = &iface->endpoints[i];
170 		if (ep->edesc == NULL)
171 			return (USBD_IOERROR);
172 		if (ep->edesc->bEndpointAddress == address)
173 			goto found;
174 	}
175 	return (USBD_BAD_ADDRESS);
176  found:
177 	if ((flags & USBD_EXCLUSIVE_USE) && ep->refcnt != 0)
178 		return (USBD_IN_USE);
179 	err = usbd_setup_pipe(iface->device, iface, ep, ival, &p);
180 	if (err)
181 		return (err);
182 	LIST_INSERT_HEAD(&iface->pipes, p, next);
183 	*pipe = p;
184 	return (USBD_NORMAL_COMPLETION);
185 }
186 
187 usbd_status
188 usbd_open_pipe_intr(usbd_interface_handle iface, u_int8_t address,
189 		    u_int8_t flags, usbd_pipe_handle *pipe,
190 		    usbd_private_handle priv, void *buffer, u_int32_t len,
191 		    usbd_callback cb, int ival)
192 {
193 	usbd_status err;
194 	usbd_xfer_handle xfer;
195 	usbd_pipe_handle ipipe;
196 
197 	DPRINTFN(3,("usbd_open_pipe_intr: address=0x%x flags=0x%x len=%d\n",
198 		    address, flags, len));
199 
200 	err = usbd_open_pipe_ival(iface, address, USBD_EXCLUSIVE_USE,
201 				  &ipipe, ival);
202 	if (err)
203 		return (err);
204 	xfer = usbd_alloc_xfer(iface->device);
205 	if (xfer == NULL) {
206 		err = USBD_NOMEM;
207 		goto bad1;
208 	}
209 	usbd_setup_xfer(xfer, ipipe, priv, buffer, len, flags,
210 	    USBD_NO_TIMEOUT, cb);
211 	ipipe->intrxfer = xfer;
212 	ipipe->repeat = 1;
213 	err = usbd_transfer(xfer);
214 	*pipe = ipipe;
215 	if (err != USBD_IN_PROGRESS)
216 		goto bad2;
217 	return (USBD_NORMAL_COMPLETION);
218 
219  bad2:
220 	ipipe->intrxfer = NULL;
221 	ipipe->repeat = 0;
222 	usbd_free_xfer(xfer);
223  bad1:
224 	usbd_close_pipe(ipipe);
225 	return (err);
226 }
227 
228 usbd_status
229 usbd_close_pipe(usbd_pipe_handle pipe)
230 {
231 	int s;
232 
233 #ifdef DIAGNOSTIC
234 	if (pipe == NULL) {
235 		printf("usbd_close_pipe: pipe==NULL\n");
236 		return (USBD_NORMAL_COMPLETION);
237 	}
238 #endif
239 
240 	usbd_lock_pipe(pipe);
241 	if (--pipe->refcnt != 0) {
242 		usbd_unlock_pipe(pipe);
243 		return (USBD_NORMAL_COMPLETION);
244 	}
245 	if (! SIMPLEQ_EMPTY(&pipe->queue)) {
246 		usbd_unlock_pipe(pipe);
247 		return (USBD_PENDING_REQUESTS);
248 	}
249 	LIST_REMOVE(pipe, next);
250 	pipe->endpoint->refcnt--;
251 	pipe->methods->close(pipe);
252 	usbd_unlock_pipe(pipe);
253 	if (pipe->intrxfer != NULL)
254 		usbd_free_xfer(pipe->intrxfer);
255 	free(pipe, M_USB);
256 	return (USBD_NORMAL_COMPLETION);
257 }
258 
259 usbd_status
260 usbd_transfer(usbd_xfer_handle xfer)
261 {
262 	usbd_pipe_handle pipe = xfer->pipe;
263 	usb_dma_t *dmap = &xfer->dmabuf;
264 	usbd_status err;
265 	unsigned int size, flags;
266 	int s;
267 
268 	DPRINTFN(5,("usbd_transfer: xfer=%p, flags=%#x, pipe=%p, running=%d\n",
269 		    xfer, xfer->flags, pipe, pipe->running));
270 
271 #ifdef USB_DEBUG
272 	if (usbdebug > 5)
273 		usbd_dump_queue(pipe);
274 #endif
275 	xfer->done = 0;
276 
277 	if (pipe->aborting)
278 		return (USBD_CANCELLED);
279 
280 	size = xfer->length;
281 	/* If there is no buffer, allocate one. */
282 	if (!(xfer->rqflags & URQ_DEV_DMABUF) && size != 0) {
283 		struct usbd_bus *bus = pipe->device->bus;
284 
285 #ifdef DIAGNOSTIC
286 		if (xfer->rqflags & URQ_AUTO_DMABUF)
287 			printf("usbd_transfer: has old buffer!\n");
288 #endif
289 		err = bus->methods->allocm(bus, dmap, size);
290 		if (err)
291 			return (err);
292 		xfer->rqflags |= URQ_AUTO_DMABUF;
293 	}
294 
295 	flags = xfer->flags;
296 
297 	/* Copy data if going out. */
298 	if (!(flags & USBD_NO_COPY) && size != 0 && !usbd_xfer_isread(xfer))
299 		memcpy(KERNADDR(dmap, 0), xfer->buffer, size);
300 
301 	/* xfer is not valid after the transfer method unless synchronous */
302 	err = pipe->methods->transfer(xfer);
303 
304 	if (err != USBD_IN_PROGRESS && err) {
305 		/* The transfer has not been queued, so free buffer. */
306 		if (xfer->rqflags & URQ_AUTO_DMABUF) {
307 			struct usbd_bus *bus = pipe->device->bus;
308 
309 			bus->methods->freem(bus, &xfer->dmabuf);
310 			xfer->rqflags &= ~URQ_AUTO_DMABUF;
311 		}
312 	}
313 
314 	if (!(flags & USBD_SYNCHRONOUS))
315 		return (err);
316 
317 	/* Sync transfer, wait for completion. */
318 	if (err != USBD_IN_PROGRESS)
319 		return (err);
320 	usbd_lock_pipe(pipe);
321 	if (!xfer->done) {
322 		if (pipe->device->bus->use_polling)
323 			panic("usbd_transfer: not done");
324 
325 		if ((flags & USBD_SYNCHRONOUS_SIG) != 0) {
326 			if (pipe->device->bus->lock)
327 				cv_wait_sig(&xfer->cv, pipe->device->bus->lock);
328 			else
329 				tsleep(xfer, PZERO|PCATCH, "usbsyn", 0);
330 		} else {
331 			if (pipe->device->bus->lock)
332 				cv_wait(&xfer->cv, pipe->device->bus->lock);
333 			else
334 				tsleep(xfer, PRIBIO, "usbsyn", 0);
335 		}
336 	}
337 	usbd_unlock_pipe(pipe);
338 	return (xfer->status);
339 }
340 
341 /* Like usbd_transfer(), but waits for completion. */
342 usbd_status
343 usbd_sync_transfer(usbd_xfer_handle xfer)
344 {
345 	xfer->flags |= USBD_SYNCHRONOUS;
346 	return (usbd_transfer(xfer));
347 }
348 
349 /* Like usbd_transfer(), but waits for completion and listens for signals. */
350 usbd_status
351 usbd_sync_transfer_sig(usbd_xfer_handle xfer)
352 {
353 	xfer->flags |= USBD_SYNCHRONOUS | USBD_SYNCHRONOUS_SIG;
354 	return (usbd_transfer(xfer));
355 }
356 
357 void *
358 usbd_alloc_buffer(usbd_xfer_handle xfer, u_int32_t size)
359 {
360 	struct usbd_bus *bus = xfer->device->bus;
361 	usbd_status err;
362 
363 #ifdef DIAGNOSTIC
364 	if (xfer->rqflags & (URQ_DEV_DMABUF | URQ_AUTO_DMABUF))
365 		printf("usbd_alloc_buffer: xfer already has a buffer\n");
366 #endif
367 	err = bus->methods->allocm(bus, &xfer->dmabuf, size);
368 	if (err)
369 		return (NULL);
370 	xfer->rqflags |= URQ_DEV_DMABUF;
371 	return (KERNADDR(&xfer->dmabuf, 0));
372 }
373 
374 void
375 usbd_free_buffer(usbd_xfer_handle xfer)
376 {
377 #ifdef DIAGNOSTIC
378 	if (!(xfer->rqflags & (URQ_DEV_DMABUF | URQ_AUTO_DMABUF))) {
379 		printf("usbd_free_buffer: no buffer\n");
380 		return;
381 	}
382 #endif
383 	xfer->rqflags &= ~(URQ_DEV_DMABUF | URQ_AUTO_DMABUF);
384 	xfer->device->bus->methods->freem(xfer->device->bus, &xfer->dmabuf);
385 }
386 
387 void *
388 usbd_get_buffer(usbd_xfer_handle xfer)
389 {
390 	if (!(xfer->rqflags & URQ_DEV_DMABUF))
391 		return (0);
392 	return (KERNADDR(&xfer->dmabuf, 0));
393 }
394 
395 usbd_xfer_handle
396 usbd_alloc_xfer(usbd_device_handle dev)
397 {
398 	usbd_xfer_handle xfer;
399 
400 	xfer = dev->bus->methods->allocx(dev->bus);
401 	if (xfer == NULL)
402 		return (NULL);
403 	xfer->device = dev;
404 	callout_init(&xfer->timeout_handle,
405 	    dev->bus->methods->get_lock ? CALLOUT_MPSAFE : 0);
406 	cv_init(&xfer->cv, "usbxfer");
407 	cv_init(&xfer->hccv, "usbhcxfer");
408 	DPRINTFN(5,("usbd_alloc_xfer() = %p\n", xfer));
409 	return (xfer);
410 }
411 
412 usbd_status
413 usbd_free_xfer(usbd_xfer_handle xfer)
414 {
415 	DPRINTFN(5,("usbd_free_xfer: %p\n", xfer));
416 	if (xfer->rqflags & (URQ_DEV_DMABUF | URQ_AUTO_DMABUF))
417 		usbd_free_buffer(xfer);
418 #if defined(DIAGNOSTIC)
419 	if (callout_pending(&xfer->timeout_handle)) {
420 		callout_stop(&xfer->timeout_handle);
421 		printf("usbd_free_xfer: timout_handle pending");
422 	}
423 #endif
424 	cv_destroy(&xfer->cv);
425 	cv_destroy(&xfer->hccv);
426 	xfer->device->bus->methods->freex(xfer->device->bus, xfer);
427 	return (USBD_NORMAL_COMPLETION);
428 }
429 
430 void
431 usbd_setup_xfer(usbd_xfer_handle xfer, usbd_pipe_handle pipe,
432 		usbd_private_handle priv, void *buffer, u_int32_t length,
433 		u_int16_t flags, u_int32_t timeout,
434 		usbd_callback callback)
435 {
436 	xfer->pipe = pipe;
437 	xfer->priv = priv;
438 	xfer->buffer = buffer;
439 	xfer->length = length;
440 	xfer->actlen = 0;
441 	xfer->flags = flags;
442 	xfer->timeout = timeout;
443 	xfer->status = USBD_NOT_STARTED;
444 	xfer->callback = callback;
445 	xfer->rqflags &= ~URQ_REQUEST;
446 	xfer->nframes = 0;
447 }
448 
449 void
450 usbd_setup_default_xfer(usbd_xfer_handle xfer, usbd_device_handle dev,
451 			usbd_private_handle priv, u_int32_t timeout,
452 			usb_device_request_t *req, void *buffer,
453 			u_int32_t length, u_int16_t flags,
454 			usbd_callback callback)
455 {
456 	xfer->pipe = dev->default_pipe;
457 	xfer->priv = priv;
458 	xfer->buffer = buffer;
459 	xfer->length = length;
460 	xfer->actlen = 0;
461 	xfer->flags = flags;
462 	xfer->timeout = timeout;
463 	xfer->status = USBD_NOT_STARTED;
464 	xfer->callback = callback;
465 	xfer->request = *req;
466 	xfer->rqflags |= URQ_REQUEST;
467 	xfer->nframes = 0;
468 }
469 
470 void
471 usbd_setup_isoc_xfer(usbd_xfer_handle xfer, usbd_pipe_handle pipe,
472 		     usbd_private_handle priv, u_int16_t *frlengths,
473 		     u_int32_t nframes, u_int16_t flags, usbd_callback callback)
474 {
475 	xfer->pipe = pipe;
476 	xfer->priv = priv;
477 	xfer->buffer = 0;
478 	xfer->length = 0;
479 	xfer->actlen = 0;
480 	xfer->flags = flags;
481 	xfer->timeout = USBD_NO_TIMEOUT;
482 	xfer->status = USBD_NOT_STARTED;
483 	xfer->callback = callback;
484 	xfer->rqflags &= ~URQ_REQUEST;
485 	xfer->frlengths = frlengths;
486 	xfer->nframes = nframes;
487 }
488 
489 void
490 usbd_get_xfer_status(usbd_xfer_handle xfer, usbd_private_handle *priv,
491 		     void **buffer, u_int32_t *count, usbd_status *status)
492 {
493 	if (priv != NULL)
494 		*priv = xfer->priv;
495 	if (buffer != NULL)
496 		*buffer = xfer->buffer;
497 	if (count != NULL)
498 		*count = xfer->actlen;
499 	if (status != NULL)
500 		*status = xfer->status;
501 }
502 
503 usb_config_descriptor_t *
504 usbd_get_config_descriptor(usbd_device_handle dev)
505 {
506 #ifdef DIAGNOSTIC
507 	if (dev == NULL) {
508 		printf("usbd_get_config_descriptor: dev == NULL\n");
509 		return (NULL);
510 	}
511 #endif
512 	return (dev->cdesc);
513 }
514 
515 usb_interface_descriptor_t *
516 usbd_get_interface_descriptor(usbd_interface_handle iface)
517 {
518 #ifdef DIAGNOSTIC
519 	if (iface == NULL) {
520 		printf("usbd_get_interface_descriptor: dev == NULL\n");
521 		return (NULL);
522 	}
523 #endif
524 	return (iface->idesc);
525 }
526 
527 usb_device_descriptor_t *
528 usbd_get_device_descriptor(usbd_device_handle dev)
529 {
530 	return (&dev->ddesc);
531 }
532 
533 usb_endpoint_descriptor_t *
534 usbd_interface2endpoint_descriptor(usbd_interface_handle iface, u_int8_t index)
535 {
536 	if (index >= iface->idesc->bNumEndpoints)
537 		return (0);
538 	return (iface->endpoints[index].edesc);
539 }
540 
541 /* Some drivers may wish to abort requests on the default pipe, *
542  * but there is no mechanism for getting a handle on it.        */
543 usbd_status
544 usbd_abort_default_pipe(struct usbd_device *device)
545 {
546 
547 	return usbd_abort_pipe(device->default_pipe);
548 }
549 
550 usbd_status
551 usbd_abort_pipe(usbd_pipe_handle pipe)
552 {
553 	usbd_status err;
554 	int s;
555 	usbd_xfer_handle intrxfer = pipe->intrxfer;
556 
557 #ifdef DIAGNOSTIC
558 	if (pipe == NULL) {
559 		printf("usbd_abort_pipe: pipe==NULL\n");
560 		return (USBD_NORMAL_COMPLETION);
561 	}
562 #endif
563 	usbd_lock_pipe(pipe);
564 	err = usbd_ar_pipe(pipe);
565 	usbd_unlock_pipe(pipe);
566 	if (pipe->intrxfer != intrxfer)
567 		usbd_free_xfer(intrxfer);
568 	return (err);
569 }
570 
571 usbd_status
572 usbd_clear_endpoint_stall(usbd_pipe_handle pipe)
573 {
574 	usbd_device_handle dev = pipe->device;
575 	usb_device_request_t req;
576 	usbd_status err;
577 
578 	DPRINTFN(8, ("usbd_clear_endpoint_stall\n"));
579 
580 	/*
581 	 * Clearing en endpoint stall resets the endpoint toggle, so
582 	 * do the same to the HC toggle.
583 	 */
584 	pipe->methods->cleartoggle(pipe);
585 
586 	req.bmRequestType = UT_WRITE_ENDPOINT;
587 	req.bRequest = UR_CLEAR_FEATURE;
588 	USETW(req.wValue, UF_ENDPOINT_HALT);
589 	USETW(req.wIndex, pipe->endpoint->edesc->bEndpointAddress);
590 	USETW(req.wLength, 0);
591 	err = usbd_do_request(dev, &req, 0);
592 #if 0
593 XXX should we do this?
594 	if (!err) {
595 		pipe->state = USBD_PIPE_ACTIVE;
596 		/* XXX activate pipe */
597 	}
598 #endif
599 	return (err);
600 }
601 
602 void
603 usbd_clear_endpoint_stall_async_cb(void *arg)
604 {
605 	usbd_pipe_handle pipe = arg;
606 	usbd_device_handle dev = pipe->device;
607 	usb_device_request_t req;
608 
609 	pipe->methods->cleartoggle(pipe);
610 
611 	req.bmRequestType = UT_WRITE_ENDPOINT;
612 	req.bRequest = UR_CLEAR_FEATURE;
613 	USETW(req.wValue, UF_ENDPOINT_HALT);
614 	USETW(req.wIndex, pipe->endpoint->edesc->bEndpointAddress);
615 	USETW(req.wLength, 0);
616 	(void)usbd_do_request_async(dev, &req, 0);
617 }
618 
619 void
620 usbd_clear_endpoint_stall_async(usbd_pipe_handle pipe)
621 {
622 
623 	usb_add_task(pipe->device, &pipe->async_task, USB_TASKQ_DRIVER);
624 }
625 
626 void
627 usbd_clear_endpoint_toggle(usbd_pipe_handle pipe)
628 {
629 	pipe->methods->cleartoggle(pipe);
630 }
631 
632 usbd_status
633 usbd_endpoint_count(usbd_interface_handle iface, u_int8_t *count)
634 {
635 #ifdef DIAGNOSTIC
636 	if (iface == NULL || iface->idesc == NULL) {
637 		printf("usbd_endpoint_count: NULL pointer\n");
638 		return (USBD_INVAL);
639 	}
640 #endif
641 	*count = iface->idesc->bNumEndpoints;
642 	return (USBD_NORMAL_COMPLETION);
643 }
644 
645 usbd_status
646 usbd_interface_count(usbd_device_handle dev, u_int8_t *count)
647 {
648 	if (dev->cdesc == NULL)
649 		return (USBD_NOT_CONFIGURED);
650 	*count = dev->cdesc->bNumInterface;
651 	return (USBD_NORMAL_COMPLETION);
652 }
653 
654 void
655 usbd_interface2device_handle(usbd_interface_handle iface,
656 			     usbd_device_handle *dev)
657 {
658 	*dev = iface->device;
659 }
660 
661 usbd_status
662 usbd_device2interface_handle(usbd_device_handle dev,
663 			     u_int8_t ifaceno, usbd_interface_handle *iface)
664 {
665 	if (dev->cdesc == NULL)
666 		return (USBD_NOT_CONFIGURED);
667 	if (ifaceno >= dev->cdesc->bNumInterface)
668 		return (USBD_INVAL);
669 	*iface = &dev->ifaces[ifaceno];
670 	return (USBD_NORMAL_COMPLETION);
671 }
672 
673 usbd_device_handle
674 usbd_pipe2device_handle(usbd_pipe_handle pipe)
675 {
676 	return (pipe->device);
677 }
678 
679 /* XXXX use altno */
680 usbd_status
681 usbd_set_interface(usbd_interface_handle iface, int altidx)
682 {
683 	usb_device_request_t req;
684 	usbd_status err;
685 	void *endpoints;
686 
687 	if (LIST_FIRST(&iface->pipes) != 0)
688 		return (USBD_IN_USE);
689 
690 	endpoints = iface->endpoints;
691 	err = usbd_fill_iface_data(iface->device, iface->index, altidx);
692 	if (err)
693 		return (err);
694 
695 	/* new setting works, we can free old endpoints */
696 	if (endpoints != NULL)
697 		free(endpoints, M_USB);
698 
699 #ifdef DIAGNOSTIC
700 	if (iface->idesc == NULL) {
701 		printf("usbd_set_interface: NULL pointer\n");
702 		return (USBD_INVAL);
703 	}
704 #endif
705 
706 	req.bmRequestType = UT_WRITE_INTERFACE;
707 	req.bRequest = UR_SET_INTERFACE;
708 	USETW(req.wValue, iface->idesc->bAlternateSetting);
709 	USETW(req.wIndex, iface->idesc->bInterfaceNumber);
710 	USETW(req.wLength, 0);
711 	return (usbd_do_request(iface->device, &req, 0));
712 }
713 
714 int
715 usbd_get_no_alts(usb_config_descriptor_t *cdesc, int ifaceno)
716 {
717 	char *p = (char *)cdesc;
718 	char *end = p + UGETW(cdesc->wTotalLength);
719 	usb_interface_descriptor_t *d;
720 	int n;
721 
722 	for (n = 0; p < end; p += d->bLength) {
723 		d = (usb_interface_descriptor_t *)p;
724 		if (p + d->bLength <= end &&
725 		    d->bDescriptorType == UDESC_INTERFACE &&
726 		    d->bInterfaceNumber == ifaceno)
727 			n++;
728 	}
729 	return (n);
730 }
731 
732 int
733 usbd_get_interface_altindex(usbd_interface_handle iface)
734 {
735 	return (iface->altindex);
736 }
737 
738 usbd_status
739 usbd_get_interface(usbd_interface_handle iface, u_int8_t *aiface)
740 {
741 	usb_device_request_t req;
742 
743 	req.bmRequestType = UT_READ_INTERFACE;
744 	req.bRequest = UR_GET_INTERFACE;
745 	USETW(req.wValue, 0);
746 	USETW(req.wIndex, iface->idesc->bInterfaceNumber);
747 	USETW(req.wLength, 1);
748 	return (usbd_do_request(iface->device, &req, aiface));
749 }
750 
751 /*** Internal routines ***/
752 
753 /* Dequeue all pipe operations, called at splusb(). */
754 Static usbd_status
755 usbd_ar_pipe(usbd_pipe_handle pipe)
756 {
757 	usbd_xfer_handle xfer;
758 
759 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
760 
761 	DPRINTFN(2,("usbd_ar_pipe: pipe=%p\n", pipe));
762 #ifdef USB_DEBUG
763 	if (usbdebug > 5)
764 		usbd_dump_queue(pipe);
765 #endif
766 	pipe->repeat = 0;
767 	pipe->aborting = 1;
768 	while ((xfer = SIMPLEQ_FIRST(&pipe->queue)) != NULL) {
769 		DPRINTFN(2,("usbd_ar_pipe: pipe=%p xfer=%p (methods=%p)\n",
770 			    pipe, xfer, pipe->methods));
771 		/* Make the HC abort it (and invoke the callback). */
772 		pipe->methods->abort(xfer);
773 		/* XXX only for non-0 usbd_clear_endpoint_stall(pipe); */
774 	}
775 	pipe->aborting = 0;
776 	return (USBD_NORMAL_COMPLETION);
777 }
778 
779 /* Called with USB lock held. */
780 void
781 usb_transfer_complete(usbd_xfer_handle xfer)
782 {
783 	usbd_pipe_handle pipe = xfer->pipe;
784 	usb_dma_t *dmap = &xfer->dmabuf;
785 	int sync = xfer->flags & USBD_SYNCHRONOUS;
786 	int erred = xfer->status == USBD_CANCELLED ||
787 	    xfer->status == USBD_TIMEOUT;
788 	int repeat, polling;
789 
790 	DPRINTFN(5, ("usb_transfer_complete: pipe=%p xfer=%p status=%d "
791 		     "actlen=%d\n", pipe, xfer, xfer->status, xfer->actlen));
792 
793 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
794 
795 #ifdef DIAGNOSTIC
796 	if (xfer->busy_free != XFER_ONQU) {
797 		printf("usb_transfer_complete: xfer=%p not busy 0x%08x\n",
798 		       xfer, xfer->busy_free);
799 	}
800 #endif
801 
802 #ifdef DIAGNOSTIC
803 	if (pipe == NULL) {
804 		printf("usb_transfer_complete: pipe==0, xfer=%p\n", xfer);
805 		return;
806 	}
807 #endif
808 	repeat = pipe->repeat;
809 	polling = pipe->device->bus->use_polling;
810 	/* XXXX */
811 	if (polling)
812 		pipe->running = 0;
813 
814 	if (!(xfer->flags & USBD_NO_COPY) && xfer->actlen != 0 &&
815 	    usbd_xfer_isread(xfer)) {
816 #ifdef DIAGNOSTIC
817 		if (xfer->actlen > xfer->length) {
818 			printf("usb_transfer_complete: actlen > len %d > %d\n",
819 			       xfer->actlen, xfer->length);
820 			xfer->actlen = xfer->length;
821 		}
822 #endif
823 		memcpy(xfer->buffer, KERNADDR(dmap, 0), xfer->actlen);
824 	}
825 
826 	/* if we allocated the buffer in usbd_transfer() we free it here. */
827 	if (xfer->rqflags & URQ_AUTO_DMABUF) {
828 		if (!repeat) {
829 			struct usbd_bus *bus = pipe->device->bus;
830 			bus->methods->freem(bus, dmap);
831 			xfer->rqflags &= ~URQ_AUTO_DMABUF;
832 		}
833 	}
834 
835 	if (!repeat) {
836 		/* Remove request from queue. */
837 #ifdef DIAGNOSTIC
838 		if (xfer != SIMPLEQ_FIRST(&pipe->queue))
839 			printf("usb_transfer_complete: bad dequeue %p != %p\n",
840 			       xfer, SIMPLEQ_FIRST(&pipe->queue));
841 		xfer->busy_free = XFER_BUSY;
842 #endif
843 		SIMPLEQ_REMOVE_HEAD(&pipe->queue, next);
844 	}
845 	DPRINTFN(5,("usb_transfer_complete: repeat=%d new head=%p\n",
846 		    repeat, SIMPLEQ_FIRST(&pipe->queue)));
847 
848 	/* Count completed transfers. */
849 	++pipe->device->bus->stats.uds_requests
850 		[pipe->endpoint->edesc->bmAttributes & UE_XFERTYPE];
851 
852 	xfer->done = 1;
853 	if (!xfer->status && xfer->actlen < xfer->length &&
854 	    !(xfer->flags & USBD_SHORT_XFER_OK)) {
855 		DPRINTFN(-1,("usb_transfer_complete: short transfer %d<%d\n",
856 			     xfer->actlen, xfer->length));
857 		xfer->status = USBD_SHORT_XFER;
858 	}
859 
860 	if (repeat) {
861 		if (xfer->callback) {
862 			if (pipe->device->bus->lock)
863 				mutex_exit(pipe->device->bus->lock);
864 			xfer->callback(xfer, xfer->priv, xfer->status);
865 			if (pipe->device->bus->lock)
866 				mutex_enter(pipe->device->bus->lock);
867 		}
868 		pipe->methods->done(xfer);
869 	} else {
870 		pipe->methods->done(xfer);
871 		if (xfer->callback) {
872 			if (pipe->device->bus->lock)
873 				mutex_exit(pipe->device->bus->lock);
874 			xfer->callback(xfer, xfer->priv, xfer->status);
875 			if (pipe->device->bus->lock)
876 				mutex_enter(pipe->device->bus->lock);
877 		}
878 	}
879 
880 	if (sync && !polling) {
881 		if (pipe->device->bus->lock)
882 			cv_broadcast(&xfer->cv);
883 		else
884 			wakeup(xfer);	/* XXXSMP ok */
885 	}
886 
887 	if (!repeat) {
888 		/* XXX should we stop the queue on all errors? */
889 		if (erred && pipe->iface != NULL)	/* not control pipe */
890 			pipe->running = 0;
891 		else
892 			usbd_start_next(pipe);
893 	}
894 }
895 
896 /* Called with USB lock held. */
897 usbd_status
898 usb_insert_transfer(usbd_xfer_handle xfer)
899 {
900 	usbd_pipe_handle pipe = xfer->pipe;
901 	usbd_status err;
902 
903 	DPRINTFN(5,("usb_insert_transfer: pipe=%p running=%d timeout=%d\n",
904 		    pipe, pipe->running, xfer->timeout));
905 
906 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
907 
908 #ifdef DIAGNOSTIC
909 	if (xfer->busy_free != XFER_BUSY) {
910 		printf("usb_insert_transfer: xfer=%p not busy 0x%08x\n",
911 		       xfer, xfer->busy_free);
912 		return (USBD_INVAL);
913 	}
914 	xfer->busy_free = XFER_ONQU;
915 #endif
916 	SIMPLEQ_INSERT_TAIL(&pipe->queue, xfer, next);
917 	if (pipe->running)
918 		err = USBD_IN_PROGRESS;
919 	else {
920 		pipe->running = 1;
921 		err = USBD_NORMAL_COMPLETION;
922 	}
923 	return (err);
924 }
925 
926 /* Called with USB lock held. */
927 void
928 usbd_start_next(usbd_pipe_handle pipe)
929 {
930 	usbd_xfer_handle xfer;
931 	usbd_status err;
932 
933 #ifdef DIAGNOSTIC
934 	if (pipe == NULL) {
935 		printf("usbd_start_next: pipe == NULL\n");
936 		return;
937 	}
938 	if (pipe->methods == NULL || pipe->methods->start == NULL) {
939 		printf("usbd_start_next: pipe=%p no start method\n", pipe);
940 		return;
941 	}
942 #endif
943 
944 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
945 
946 	/* Get next request in queue. */
947 	xfer = SIMPLEQ_FIRST(&pipe->queue);
948 	DPRINTFN(5, ("usbd_start_next: pipe=%p, xfer=%p\n", pipe, xfer));
949 	if (xfer == NULL) {
950 		pipe->running = 0;
951 	} else {
952 		if (pipe->device->bus->lock)
953 			mutex_exit(pipe->device->bus->lock);
954 		err = pipe->methods->start(xfer);
955 		if (pipe->device->bus->lock)
956 			mutex_enter(pipe->device->bus->lock);
957 		if (err != USBD_IN_PROGRESS) {
958 			printf("usbd_start_next: error=%d\n", err);
959 			pipe->running = 0;
960 			/* XXX do what? */
961 		}
962 	}
963 
964 	KASSERT(pipe->device->bus->lock == NULL || mutex_owned(pipe->device->bus->lock));
965 }
966 
967 usbd_status
968 usbd_do_request(usbd_device_handle dev, usb_device_request_t *req, void *data)
969 {
970 	return (usbd_do_request_flags(dev, req, data, 0, 0,
971 				      USBD_DEFAULT_TIMEOUT));
972 }
973 
974 usbd_status
975 usbd_do_request_flags(usbd_device_handle dev, usb_device_request_t *req,
976 		      void *data, u_int16_t flags, int *actlen, u_int32_t timo)
977 {
978 	return (usbd_do_request_flags_pipe(dev, dev->default_pipe, req,
979 					   data, flags, actlen, timo));
980 }
981 
982 usbd_status
983 usbd_do_request_flags_pipe(usbd_device_handle dev, usbd_pipe_handle pipe,
984 	usb_device_request_t *req, void *data, u_int16_t flags, int *actlen,
985 	u_int32_t timeout)
986 {
987 	usbd_xfer_handle xfer;
988 	usbd_status err;
989 
990 #ifdef DIAGNOSTIC
991 	if (cpu_intr_p() || cpu_softintr_p()) {
992 		printf("usbd_do_request: not in process context\n");
993 		return (USBD_INVAL);
994 	}
995 #endif
996 
997 	xfer = usbd_alloc_xfer(dev);
998 	if (xfer == NULL)
999 		return (USBD_NOMEM);
1000 	usbd_setup_default_xfer(xfer, dev, 0, timeout, req,
1001 				data, UGETW(req->wLength), flags, 0);
1002 	xfer->pipe = pipe;
1003 	err = usbd_sync_transfer(xfer);
1004 #if defined(USB_DEBUG) || defined(DIAGNOSTIC)
1005 	if (xfer->actlen > xfer->length) {
1006 		DPRINTF(("%s: overrun addr=%d type=0x%02x req=0x"
1007 			 "%02x val=%d index=%d rlen=%d length=%d actlen=%d\n",
1008 			 __func__, dev->address, xfer->request.bmRequestType,
1009 			 xfer->request.bRequest, UGETW(xfer->request.wValue),
1010 			 UGETW(xfer->request.wIndex),
1011 			 UGETW(xfer->request.wLength),
1012 			 xfer->length, xfer->actlen));
1013 	}
1014 #endif
1015 	if (actlen != NULL)
1016 		*actlen = xfer->actlen;
1017 	if (err == USBD_STALLED) {
1018 		/*
1019 		 * The control endpoint has stalled.  Control endpoints
1020 		 * should not halt, but some may do so anyway so clear
1021 		 * any halt condition.
1022 		 */
1023 		usb_device_request_t treq;
1024 		usb_status_t status;
1025 		u_int16_t s;
1026 		usbd_status nerr;
1027 
1028 		treq.bmRequestType = UT_READ_ENDPOINT;
1029 		treq.bRequest = UR_GET_STATUS;
1030 		USETW(treq.wValue, 0);
1031 		USETW(treq.wIndex, 0);
1032 		USETW(treq.wLength, sizeof(usb_status_t));
1033 		usbd_setup_default_xfer(xfer, dev, 0, USBD_DEFAULT_TIMEOUT,
1034 					   &treq, &status,sizeof(usb_status_t),
1035 					   0, 0);
1036 		nerr = usbd_sync_transfer(xfer);
1037 		if (nerr)
1038 			goto bad;
1039 		s = UGETW(status.wStatus);
1040 		DPRINTF(("usbd_do_request: status = 0x%04x\n", s));
1041 		if (!(s & UES_HALT))
1042 			goto bad;
1043 		treq.bmRequestType = UT_WRITE_ENDPOINT;
1044 		treq.bRequest = UR_CLEAR_FEATURE;
1045 		USETW(treq.wValue, UF_ENDPOINT_HALT);
1046 		USETW(treq.wIndex, 0);
1047 		USETW(treq.wLength, 0);
1048 		usbd_setup_default_xfer(xfer, dev, 0, USBD_DEFAULT_TIMEOUT,
1049 					   &treq, &status, 0, 0, 0);
1050 		nerr = usbd_sync_transfer(xfer);
1051 		if (nerr)
1052 			goto bad;
1053 	}
1054 
1055  bad:
1056 	if (err) {
1057 		DPRINTF(("%s: returning err=%s\n", __func__, usbd_errstr(err)));
1058 	}
1059 	usbd_free_xfer(xfer);
1060 	return (err);
1061 }
1062 
1063 void
1064 usbd_do_request_async_cb(usbd_xfer_handle xfer,
1065     usbd_private_handle priv, usbd_status status)
1066 {
1067 #if defined(USB_DEBUG) || defined(DIAGNOSTIC)
1068 	if (xfer->actlen > xfer->length) {
1069 		DPRINTF(("usbd_do_request: overrun addr=%d type=0x%02x req=0x"
1070 			 "%02x val=%d index=%d rlen=%d length=%d actlen=%d\n",
1071 			 xfer->pipe->device->address,
1072 			 xfer->request.bmRequestType,
1073 			 xfer->request.bRequest, UGETW(xfer->request.wValue),
1074 			 UGETW(xfer->request.wIndex),
1075 			 UGETW(xfer->request.wLength),
1076 			 xfer->length, xfer->actlen));
1077 	}
1078 #endif
1079 	usbd_free_xfer(xfer);
1080 }
1081 
1082 /*
1083  * Execute a request without waiting for completion.
1084  * Can be used from interrupt context.
1085  */
1086 usbd_status
1087 usbd_do_request_async(usbd_device_handle dev, usb_device_request_t *req,
1088 		      void *data)
1089 {
1090 	usbd_xfer_handle xfer;
1091 	usbd_status err;
1092 
1093 	xfer = usbd_alloc_xfer(dev);
1094 	if (xfer == NULL)
1095 		return (USBD_NOMEM);
1096 	usbd_setup_default_xfer(xfer, dev, 0, USBD_DEFAULT_TIMEOUT, req,
1097 	    data, UGETW(req->wLength), 0, usbd_do_request_async_cb);
1098 	err = usbd_transfer(xfer);
1099 	if (err != USBD_IN_PROGRESS) {
1100 		usbd_free_xfer(xfer);
1101 		return (err);
1102 	}
1103 	return (USBD_NORMAL_COMPLETION);
1104 }
1105 
1106 const struct usbd_quirks *
1107 usbd_get_quirks(usbd_device_handle dev)
1108 {
1109 #ifdef DIAGNOSTIC
1110 	if (dev == NULL) {
1111 		printf("usbd_get_quirks: dev == NULL\n");
1112 		return 0;
1113 	}
1114 #endif
1115 	return (dev->quirks);
1116 }
1117 
1118 /* XXX do periodic free() of free list */
1119 
1120 /*
1121  * Called from keyboard driver when in polling mode.
1122  */
1123 void
1124 usbd_dopoll(usbd_interface_handle iface)
1125 {
1126 	iface->device->bus->methods->do_poll(iface->device->bus);
1127 }
1128 
1129 /*
1130  * XXX use this more???  use_polling it touched manually all over
1131  */
1132 void
1133 usbd_set_polling(usbd_device_handle dev, int on)
1134 {
1135 	if (on)
1136 		dev->bus->use_polling++;
1137 	else
1138 		dev->bus->use_polling--;
1139 
1140 	/* Kick the host controller when switching modes */
1141 	if (dev->bus->lock)
1142 		mutex_enter(dev->bus->lock);
1143 	(*dev->bus->methods->soft_intr)(dev->bus);
1144 	if (dev->bus->lock)
1145 		mutex_exit(dev->bus->lock);
1146 
1147 }
1148 
1149 
1150 usb_endpoint_descriptor_t *
1151 usbd_get_endpoint_descriptor(usbd_interface_handle iface, u_int8_t address)
1152 {
1153 	struct usbd_endpoint *ep;
1154 	int i;
1155 
1156 	for (i = 0; i < iface->idesc->bNumEndpoints; i++) {
1157 		ep = &iface->endpoints[i];
1158 		if (ep->edesc->bEndpointAddress == address)
1159 			return (iface->endpoints[i].edesc);
1160 	}
1161 	return (0);
1162 }
1163 
1164 /*
1165  * usbd_ratecheck() can limit the number of error messages that occurs.
1166  * When a device is unplugged it may take up to 0.25s for the hub driver
1167  * to notice it.  If the driver continuosly tries to do I/O operations
1168  * this can generate a large number of messages.
1169  */
1170 int
1171 usbd_ratecheck(struct timeval *last)
1172 {
1173 	static struct timeval errinterval = { 0, 250000 }; /* 0.25 s*/
1174 
1175 	return (ratecheck(last, &errinterval));
1176 }
1177 
1178 /*
1179  * Search for a vendor/product pair in an array.  The item size is
1180  * given as an argument.
1181  */
1182 const struct usb_devno *
1183 usb_match_device(const struct usb_devno *tbl, u_int nentries, u_int sz,
1184 		 u_int16_t vendor, u_int16_t product)
1185 {
1186 	while (nentries-- > 0) {
1187 		u_int16_t tproduct = tbl->ud_product;
1188 		if (tbl->ud_vendor == vendor &&
1189 		    (tproduct == product || tproduct == USB_PRODUCT_ANY))
1190 			return (tbl);
1191 		tbl = (const struct usb_devno *)((const char *)tbl + sz);
1192 	}
1193 	return (NULL);
1194 }
1195 
1196 
1197 void
1198 usb_desc_iter_init(usbd_device_handle dev, usbd_desc_iter_t *iter)
1199 {
1200 	const usb_config_descriptor_t *cd = usbd_get_config_descriptor(dev);
1201 
1202         iter->cur = (const uByte *)cd;
1203         iter->end = (const uByte *)cd + UGETW(cd->wTotalLength);
1204 }
1205 
1206 const usb_descriptor_t *
1207 usb_desc_iter_next(usbd_desc_iter_t *iter)
1208 {
1209 	const usb_descriptor_t *desc;
1210 
1211 	if (iter->cur + sizeof(usb_descriptor_t) >= iter->end) {
1212 		if (iter->cur != iter->end)
1213 			printf("usb_desc_iter_next: bad descriptor\n");
1214 		return NULL;
1215 	}
1216 	desc = (const usb_descriptor_t *)iter->cur;
1217 	if (desc->bLength == 0) {
1218 		printf("usb_desc_iter_next: descriptor length = 0\n");
1219 		return NULL;
1220 	}
1221 	iter->cur += desc->bLength;
1222 	if (iter->cur > iter->end) {
1223 		printf("usb_desc_iter_next: descriptor length too large\n");
1224 		return NULL;
1225 	}
1226 	return desc;
1227 }
1228 
1229 usbd_status
1230 usbd_get_string(usbd_device_handle dev, int si, char *buf)
1231 {
1232 	return usbd_get_string0(dev, si, buf, 1);
1233 }
1234 
1235 usbd_status
1236 usbd_get_string0(usbd_device_handle dev, int si, char *buf, int unicode)
1237 {
1238 	int swap = dev->quirks->uq_flags & UQ_SWAP_UNICODE;
1239 	usb_string_descriptor_t us;
1240 	char *s;
1241 	int i, n;
1242 	u_int16_t c;
1243 	usbd_status err;
1244 	int size;
1245 
1246 	buf[0] = '\0';
1247 	if (si == 0)
1248 		return (USBD_INVAL);
1249 	if (dev->quirks->uq_flags & UQ_NO_STRINGS)
1250 		return (USBD_STALLED);
1251 	if (dev->langid == USBD_NOLANG) {
1252 		/* Set up default language */
1253 		err = usbd_get_string_desc(dev, USB_LANGUAGE_TABLE, 0, &us,
1254 		    &size);
1255 		if (err || size < 4) {
1256 			DPRINTFN(-1,("usbd_get_string: getting lang failed, using 0\n"));
1257 			dev->langid = 0; /* Well, just pick something then */
1258 		} else {
1259 			/* Pick the first language as the default. */
1260 			dev->langid = UGETW(us.bString[0]);
1261 		}
1262 	}
1263 	err = usbd_get_string_desc(dev, si, dev->langid, &us, &size);
1264 	if (err)
1265 		return (err);
1266 	s = buf;
1267 	n = size / 2 - 1;
1268 	if (unicode) {
1269 		for (i = 0; i < n; i++) {
1270 			c = UGETW(us.bString[i]);
1271 			if (swap)
1272 				c = (c >> 8) | (c << 8);
1273 			s += wput_utf8(s, 3, c);
1274 		}
1275 		*s++ = 0;
1276 	}
1277 #ifdef COMPAT_30
1278 	else {
1279 		for (i = 0; i < n; i++) {
1280 			c = UGETW(us.bString[i]);
1281 			if (swap)
1282 				c = (c >> 8) | (c << 8);
1283 			*s++ = (c < 0x80) ? c : '?';
1284 		}
1285 		*s++ = 0;
1286 	}
1287 #endif
1288 	return (USBD_NORMAL_COMPLETION);
1289 }
1290