xref: /freebsd/lib/libusb/libusb20.c (revision 206b73d0)
1 /* $FreeBSD$ */
2 /*-
3  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4  *
5  * Copyright (c) 2008-2009 Hans Petter Selasky. All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #ifdef LIBUSB_GLOBAL_INCLUDE_FILE
30 #include LIBUSB_GLOBAL_INCLUDE_FILE
31 #else
32 #include <ctype.h>
33 #include <poll.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 #include <time.h>
38 #include <sys/queue.h>
39 #endif
40 
41 #include "libusb20.h"
42 #include "libusb20_desc.h"
43 #include "libusb20_int.h"
44 
45 static int
46 dummy_int(void)
47 {
48 	return (LIBUSB20_ERROR_NOT_SUPPORTED);
49 }
50 
51 static void
52 dummy_void(void)
53 {
54 	return;
55 }
56 
57 static void
58 dummy_callback(struct libusb20_transfer *xfer)
59 {
60 	;				/* style fix */
61 	switch (libusb20_tr_get_status(xfer)) {
62 	case LIBUSB20_TRANSFER_START:
63 		libusb20_tr_submit(xfer);
64 		break;
65 	default:
66 		/* complete or error */
67 		break;
68 	}
69 	return;
70 }
71 
72 #define	dummy_get_config_desc_full (void *)dummy_int
73 #define	dummy_get_config_index (void *)dummy_int
74 #define	dummy_set_config_index (void *)dummy_int
75 #define	dummy_set_alt_index (void *)dummy_int
76 #define	dummy_reset_device (void *)dummy_int
77 #define	dummy_check_connected (void *)dummy_int
78 #define	dummy_set_power_mode (void *)dummy_int
79 #define	dummy_get_power_mode (void *)dummy_int
80 #define	dummy_get_power_usage (void *)dummy_int
81 #define	dummy_kernel_driver_active (void *)dummy_int
82 #define	dummy_detach_kernel_driver (void *)dummy_int
83 #define	dummy_do_request_sync (void *)dummy_int
84 #define	dummy_tr_open (void *)dummy_int
85 #define	dummy_tr_close (void *)dummy_int
86 #define	dummy_tr_clear_stall_sync (void *)dummy_int
87 #define	dummy_process (void *)dummy_int
88 #define	dummy_dev_info (void *)dummy_int
89 #define	dummy_dev_get_iface_driver (void *)dummy_int
90 
91 #define	dummy_tr_submit (void *)dummy_void
92 #define	dummy_tr_cancel_async (void *)dummy_void
93 
94 static const struct libusb20_device_methods libusb20_dummy_methods = {
95 	LIBUSB20_DEVICE(LIBUSB20_DECLARE, dummy)
96 };
97 
98 void
99 libusb20_tr_callback_wrapper(struct libusb20_transfer *xfer)
100 {
101 	;				/* style fix */
102 
103 repeat:
104 
105 	if (!xfer->is_pending) {
106 		xfer->status = LIBUSB20_TRANSFER_START;
107 	} else {
108 		xfer->is_pending = 0;
109 	}
110 
111 	xfer->callback(xfer);
112 
113 	if (xfer->is_restart) {
114 		xfer->is_restart = 0;
115 		goto repeat;
116 	}
117 	if (xfer->is_draining &&
118 	    (!xfer->is_pending)) {
119 		xfer->is_draining = 0;
120 		xfer->status = LIBUSB20_TRANSFER_DRAINED;
121 		xfer->callback(xfer);
122 	}
123 	return;
124 }
125 
126 int
127 libusb20_tr_close(struct libusb20_transfer *xfer)
128 {
129 	int error;
130 
131 	if (!xfer->is_opened) {
132 		return (LIBUSB20_ERROR_OTHER);
133 	}
134 	error = xfer->pdev->methods->tr_close(xfer);
135 
136 	if (xfer->pLength) {
137 		free(xfer->pLength);
138 	}
139 	if (xfer->ppBuffer) {
140 		free(xfer->ppBuffer);
141 	}
142 	/* reset variable fields in case the transfer is opened again */
143 	xfer->priv_sc0 = NULL;
144 	xfer->priv_sc1 = NULL;
145 	xfer->is_opened = 0;
146 	xfer->is_pending = 0;
147 	xfer->is_cancel = 0;
148 	xfer->is_draining = 0;
149 	xfer->is_restart = 0;
150 	xfer->status = 0;
151 	xfer->flags = 0;
152 	xfer->nFrames = 0;
153 	xfer->aFrames = 0;
154 	xfer->timeout = 0;
155 	xfer->maxFrames = 0;
156 	xfer->maxTotalLength = 0;
157 	xfer->maxPacketLen = 0;
158 	return (error);
159 }
160 
161 int
162 libusb20_tr_open(struct libusb20_transfer *xfer, uint32_t MaxBufSize,
163     uint32_t MaxFrameCount, uint8_t ep_no)
164 {
165 	return (libusb20_tr_open_stream(xfer, MaxBufSize, MaxFrameCount, ep_no, 0));
166 }
167 
168 int
169 libusb20_tr_open_stream(struct libusb20_transfer *xfer, uint32_t MaxBufSize,
170     uint32_t MaxFrameCount, uint8_t ep_no, uint16_t stream_id)
171 {
172 	uint32_t size;
173 	uint8_t pre_scale;
174 	int error;
175 
176 	if (xfer->is_opened)
177 		return (LIBUSB20_ERROR_BUSY);
178 	if (MaxFrameCount & LIBUSB20_MAX_FRAME_PRE_SCALE) {
179 		MaxFrameCount &= ~LIBUSB20_MAX_FRAME_PRE_SCALE;
180 		/*
181 		 * The kernel can setup 8 times more frames when
182 		 * pre-scaling ISOCHRONOUS transfers. Make sure the
183 		 * length and pointer buffers are big enough:
184 		 */
185 		MaxFrameCount *= 8;
186 		pre_scale = 1;
187 	} else {
188 		pre_scale = 0;
189 	}
190 	if (MaxFrameCount == 0)
191 		return (LIBUSB20_ERROR_INVALID_PARAM);
192 
193 	xfer->maxFrames = MaxFrameCount;
194 
195 	size = MaxFrameCount * sizeof(xfer->pLength[0]);
196 	xfer->pLength = malloc(size);
197 	if (xfer->pLength == NULL) {
198 		return (LIBUSB20_ERROR_NO_MEM);
199 	}
200 	memset(xfer->pLength, 0, size);
201 
202 	size = MaxFrameCount * sizeof(xfer->ppBuffer[0]);
203 	xfer->ppBuffer = malloc(size);
204 	if (xfer->ppBuffer == NULL) {
205 		free(xfer->pLength);
206 		return (LIBUSB20_ERROR_NO_MEM);
207 	}
208 	memset(xfer->ppBuffer, 0, size);
209 
210 	if (pre_scale) {
211 		error = xfer->pdev->methods->tr_open(xfer, MaxBufSize,
212 		    MaxFrameCount / 8, ep_no, stream_id, 1);
213 	} else {
214 		error = xfer->pdev->methods->tr_open(xfer, MaxBufSize,
215 		    MaxFrameCount, ep_no, stream_id, 0);
216 	}
217 
218 	if (error) {
219 		free(xfer->ppBuffer);
220 		free(xfer->pLength);
221 	} else {
222 		xfer->is_opened = 1;
223 	}
224 	return (error);
225 }
226 
227 struct libusb20_transfer *
228 libusb20_tr_get_pointer(struct libusb20_device *pdev, uint16_t trIndex)
229 {
230 	if (trIndex >= pdev->nTransfer) {
231 		return (NULL);
232 	}
233 	return (pdev->pTransfer + trIndex);
234 }
235 
236 uint32_t
237 libusb20_tr_get_actual_frames(struct libusb20_transfer *xfer)
238 {
239 	return (xfer->aFrames);
240 }
241 
242 uint16_t
243 libusb20_tr_get_time_complete(struct libusb20_transfer *xfer)
244 {
245 	return (xfer->timeComplete);
246 }
247 
248 uint32_t
249 libusb20_tr_get_actual_length(struct libusb20_transfer *xfer)
250 {
251 	uint32_t x;
252 	uint32_t actlen = 0;
253 
254 	for (x = 0; x != xfer->aFrames; x++) {
255 		actlen += xfer->pLength[x];
256 	}
257 	return (actlen);
258 }
259 
260 uint32_t
261 libusb20_tr_get_max_frames(struct libusb20_transfer *xfer)
262 {
263 	return (xfer->maxFrames);
264 }
265 
266 uint32_t
267 libusb20_tr_get_max_packet_length(struct libusb20_transfer *xfer)
268 {
269 	/*
270 	 * Special Case NOTE: If the packet multiplier is non-zero for
271 	 * High Speed USB, the value returned is equal to
272 	 * "wMaxPacketSize * multiplier" !
273 	 */
274 	return (xfer->maxPacketLen);
275 }
276 
277 uint32_t
278 libusb20_tr_get_max_total_length(struct libusb20_transfer *xfer)
279 {
280 	return (xfer->maxTotalLength);
281 }
282 
283 uint8_t
284 libusb20_tr_get_status(struct libusb20_transfer *xfer)
285 {
286 	return (xfer->status);
287 }
288 
289 uint8_t
290 libusb20_tr_pending(struct libusb20_transfer *xfer)
291 {
292 	return (xfer->is_pending);
293 }
294 
295 void   *
296 libusb20_tr_get_priv_sc0(struct libusb20_transfer *xfer)
297 {
298 	return (xfer->priv_sc0);
299 }
300 
301 void   *
302 libusb20_tr_get_priv_sc1(struct libusb20_transfer *xfer)
303 {
304 	return (xfer->priv_sc1);
305 }
306 
307 void
308 libusb20_tr_stop(struct libusb20_transfer *xfer)
309 {
310 	if (!xfer->is_opened) {
311 		/* transfer is not opened */
312 		return;
313 	}
314 	if (!xfer->is_pending) {
315 		/* transfer not pending */
316 		return;
317 	}
318 	if (xfer->is_cancel) {
319 		/* already cancelling */
320 		return;
321 	}
322 	xfer->is_cancel = 1;		/* we are cancelling */
323 
324 	xfer->pdev->methods->tr_cancel_async(xfer);
325 	return;
326 }
327 
328 void
329 libusb20_tr_drain(struct libusb20_transfer *xfer)
330 {
331 	if (!xfer->is_opened) {
332 		/* transfer is not opened */
333 		return;
334 	}
335 	/* make sure that we are cancelling */
336 	libusb20_tr_stop(xfer);
337 
338 	if (xfer->is_pending) {
339 		xfer->is_draining = 1;
340 	}
341 	return;
342 }
343 
344 void
345 libusb20_tr_clear_stall_sync(struct libusb20_transfer *xfer)
346 {
347 	xfer->pdev->methods->tr_clear_stall_sync(xfer);
348 	return;
349 }
350 
351 void
352 libusb20_tr_set_buffer(struct libusb20_transfer *xfer, void *buffer, uint16_t frIndex)
353 {
354 	xfer->ppBuffer[frIndex] = libusb20_pass_ptr(buffer);
355 	return;
356 }
357 
358 void
359 libusb20_tr_set_callback(struct libusb20_transfer *xfer, libusb20_tr_callback_t *cb)
360 {
361 	xfer->callback = cb;
362 	return;
363 }
364 
365 void
366 libusb20_tr_set_flags(struct libusb20_transfer *xfer, uint8_t flags)
367 {
368 	xfer->flags = flags;
369 	return;
370 }
371 
372 uint32_t
373 libusb20_tr_get_length(struct libusb20_transfer *xfer, uint16_t frIndex)
374 {
375 	return (xfer->pLength[frIndex]);
376 }
377 
378 void
379 libusb20_tr_set_length(struct libusb20_transfer *xfer, uint32_t length, uint16_t frIndex)
380 {
381 	xfer->pLength[frIndex] = length;
382 	return;
383 }
384 
385 void
386 libusb20_tr_set_priv_sc0(struct libusb20_transfer *xfer, void *sc0)
387 {
388 	xfer->priv_sc0 = sc0;
389 	return;
390 }
391 
392 void
393 libusb20_tr_set_priv_sc1(struct libusb20_transfer *xfer, void *sc1)
394 {
395 	xfer->priv_sc1 = sc1;
396 	return;
397 }
398 
399 void
400 libusb20_tr_set_timeout(struct libusb20_transfer *xfer, uint32_t timeout)
401 {
402 	xfer->timeout = timeout;
403 	return;
404 }
405 
406 void
407 libusb20_tr_set_total_frames(struct libusb20_transfer *xfer, uint32_t nFrames)
408 {
409 	if (nFrames > xfer->maxFrames) {
410 		/* should not happen */
411 		nFrames = xfer->maxFrames;
412 	}
413 	xfer->nFrames = nFrames;
414 	return;
415 }
416 
417 void
418 libusb20_tr_setup_bulk(struct libusb20_transfer *xfer, void *pBuf, uint32_t length, uint32_t timeout)
419 {
420 	xfer->ppBuffer[0] = libusb20_pass_ptr(pBuf);
421 	xfer->pLength[0] = length;
422 	xfer->timeout = timeout;
423 	xfer->nFrames = 1;
424 	return;
425 }
426 
427 void
428 libusb20_tr_setup_control(struct libusb20_transfer *xfer, void *psetup, void *pBuf, uint32_t timeout)
429 {
430 	uint16_t len;
431 
432 	xfer->ppBuffer[0] = libusb20_pass_ptr(psetup);
433 	xfer->pLength[0] = 8;		/* fixed */
434 	xfer->timeout = timeout;
435 
436 	len = ((uint8_t *)psetup)[6] | (((uint8_t *)psetup)[7] << 8);
437 
438 	if (len != 0) {
439 		xfer->nFrames = 2;
440 		xfer->ppBuffer[1] = libusb20_pass_ptr(pBuf);
441 		xfer->pLength[1] = len;
442 	} else {
443 		xfer->nFrames = 1;
444 	}
445 	return;
446 }
447 
448 void
449 libusb20_tr_setup_intr(struct libusb20_transfer *xfer, void *pBuf, uint32_t length, uint32_t timeout)
450 {
451 	xfer->ppBuffer[0] = libusb20_pass_ptr(pBuf);
452 	xfer->pLength[0] = length;
453 	xfer->timeout = timeout;
454 	xfer->nFrames = 1;
455 	return;
456 }
457 
458 void
459 libusb20_tr_setup_isoc(struct libusb20_transfer *xfer, void *pBuf, uint32_t length, uint16_t frIndex)
460 {
461 	if (frIndex >= xfer->maxFrames) {
462 		/* should not happen */
463 		return;
464 	}
465 	xfer->ppBuffer[frIndex] = libusb20_pass_ptr(pBuf);
466 	xfer->pLength[frIndex] = length;
467 	return;
468 }
469 
470 uint8_t
471 libusb20_tr_bulk_intr_sync(struct libusb20_transfer *xfer,
472     void *pbuf, uint32_t length, uint32_t *pactlen,
473     uint32_t timeout)
474 {
475 	struct libusb20_device *pdev = xfer->pdev;
476 	uint32_t transfer_max;
477 	uint32_t transfer_act;
478 	uint8_t retval;
479 
480 	/* set some sensible default value */
481 	if (pactlen != NULL)
482 		*pactlen = 0;
483 
484 	/* check for error condition */
485 	if (libusb20_tr_pending(xfer))
486 		return (LIBUSB20_ERROR_OTHER);
487 
488 	do {
489 		/* compute maximum transfer length */
490 		transfer_max =
491 		    libusb20_tr_get_max_total_length(xfer);
492 
493 		if (transfer_max > length)
494 			transfer_max = length;
495 
496 		/* setup bulk or interrupt transfer */
497 		libusb20_tr_setup_bulk(xfer, pbuf,
498 		    transfer_max, timeout);
499 
500 		/* start the transfer */
501 		libusb20_tr_start(xfer);
502 
503 		/* wait for transfer completion */
504 		while (libusb20_dev_process(pdev) == 0) {
505 
506 			if (libusb20_tr_pending(xfer) == 0)
507 				break;
508 
509 			libusb20_dev_wait_process(pdev, -1);
510 		}
511 
512 		transfer_act = libusb20_tr_get_actual_length(xfer);
513 
514 		/* update actual length, if any */
515 		if (pactlen != NULL)
516 			pactlen[0] += transfer_act;
517 
518 		/* check transfer status */
519 		retval = libusb20_tr_get_status(xfer);
520 		if (retval)
521 			break;
522 
523 		/* check for short transfer */
524 		if (transfer_act != transfer_max)
525 			break;
526 
527 		/* update buffer pointer and length */
528 		pbuf = ((uint8_t *)pbuf) + transfer_max;
529 		length = length - transfer_max;
530 
531 	} while (length != 0);
532 
533 	return (retval);
534 }
535 
536 void
537 libusb20_tr_submit(struct libusb20_transfer *xfer)
538 {
539 	if (!xfer->is_opened) {
540 		/* transfer is not opened */
541 		return;
542 	}
543 	if (xfer->is_pending) {
544 		/* should not happen */
545 		return;
546 	}
547 	xfer->is_pending = 1;		/* we are pending */
548 	xfer->is_cancel = 0;		/* not cancelling */
549 	xfer->is_restart = 0;		/* not restarting */
550 
551 	xfer->pdev->methods->tr_submit(xfer);
552 	return;
553 }
554 
555 void
556 libusb20_tr_start(struct libusb20_transfer *xfer)
557 {
558 	if (!xfer->is_opened) {
559 		/* transfer is not opened */
560 		return;
561 	}
562 	if (xfer->is_pending) {
563 		if (xfer->is_cancel) {
564 			/* cancelling - restart */
565 			xfer->is_restart = 1;
566 		}
567 		/* transfer not pending */
568 		return;
569 	}
570 	/* get into the callback */
571 	libusb20_tr_callback_wrapper(xfer);
572 	return;
573 }
574 
575 /* USB device operations */
576 
577 int
578 libusb20_dev_close(struct libusb20_device *pdev)
579 {
580 	struct libusb20_transfer *xfer;
581 	uint16_t x;
582 	int error = 0;
583 
584 	if (!pdev->is_opened) {
585 		return (LIBUSB20_ERROR_OTHER);
586 	}
587 	for (x = 0; x != pdev->nTransfer; x++) {
588 		xfer = pdev->pTransfer + x;
589 
590 		if (!xfer->is_opened) {
591 			/* transfer is not opened */
592 			continue;
593 		}
594 
595 		libusb20_tr_drain(xfer);
596 
597 		libusb20_tr_close(xfer);
598 	}
599 
600 	if (pdev->pTransfer != NULL) {
601 		free(pdev->pTransfer);
602 		pdev->pTransfer = NULL;
603 	}
604 	error = pdev->beMethods->close_device(pdev);
605 
606 	pdev->methods = &libusb20_dummy_methods;
607 
608 	pdev->is_opened = 0;
609 
610 	/*
611 	 * The following variable is only used by the libusb v0.1
612 	 * compat layer:
613 	 */
614 	pdev->claimed_interface = 0;
615 
616 	/*
617 	 * The following variable is only used by the libusb v1.0
618 	 * compat layer:
619 	 */
620 	pdev->auto_detach = 0;
621 
622 	return (error);
623 }
624 
625 int
626 libusb20_dev_detach_kernel_driver(struct libusb20_device *pdev, uint8_t ifaceIndex)
627 {
628 	int error;
629 
630 	error = pdev->methods->detach_kernel_driver(pdev, ifaceIndex);
631 	return (error);
632 }
633 
634 struct LIBUSB20_DEVICE_DESC_DECODED *
635 libusb20_dev_get_device_desc(struct libusb20_device *pdev)
636 {
637 	return (&(pdev->ddesc));
638 }
639 
640 int
641 libusb20_dev_get_fd(struct libusb20_device *pdev)
642 {
643 	return (pdev->file);
644 }
645 
646 int
647 libusb20_dev_kernel_driver_active(struct libusb20_device *pdev, uint8_t ifaceIndex)
648 {
649 	int error;
650 
651 	error = pdev->methods->kernel_driver_active(pdev, ifaceIndex);
652 	return (error);
653 }
654 
655 int
656 libusb20_dev_open(struct libusb20_device *pdev, uint16_t nTransferMax)
657 {
658 	struct libusb20_transfer *xfer;
659 	uint32_t size;
660 	uint16_t x;
661 	int error;
662 
663 	if (pdev->is_opened) {
664 		return (LIBUSB20_ERROR_BUSY);
665 	}
666 	if (nTransferMax >= 256) {
667 		return (LIBUSB20_ERROR_INVALID_PARAM);
668 	} else if (nTransferMax != 0) {
669 		size = sizeof(pdev->pTransfer[0]) * nTransferMax;
670 		pdev->pTransfer = malloc(size);
671 		if (pdev->pTransfer == NULL) {
672 			return (LIBUSB20_ERROR_NO_MEM);
673 		}
674 		memset(pdev->pTransfer, 0, size);
675 	}
676 	/* initialise all transfers */
677 	for (x = 0; x != nTransferMax; x++) {
678 
679 		xfer = pdev->pTransfer + x;
680 
681 		xfer->pdev = pdev;
682 		xfer->trIndex = x;
683 		xfer->callback = &dummy_callback;
684 	}
685 
686 	/* set "nTransfer" early */
687 	pdev->nTransfer = nTransferMax;
688 
689 	error = pdev->beMethods->open_device(pdev, nTransferMax);
690 
691 	if (error) {
692 		if (pdev->pTransfer != NULL) {
693 			free(pdev->pTransfer);
694 			pdev->pTransfer = NULL;
695 		}
696 		pdev->file = -1;
697 		pdev->file_ctrl = -1;
698 		pdev->nTransfer = 0;
699 	} else {
700 		pdev->is_opened = 1;
701 	}
702 	return (error);
703 }
704 
705 int
706 libusb20_dev_reset(struct libusb20_device *pdev)
707 {
708 	int error;
709 
710 	error = pdev->methods->reset_device(pdev);
711 	return (error);
712 }
713 
714 int
715 libusb20_dev_check_connected(struct libusb20_device *pdev)
716 {
717 	int error;
718 
719 	error = pdev->methods->check_connected(pdev);
720 	return (error);
721 }
722 
723 int
724 libusb20_dev_set_power_mode(struct libusb20_device *pdev, uint8_t power_mode)
725 {
726 	int error;
727 
728 	error = pdev->methods->set_power_mode(pdev, power_mode);
729 	return (error);
730 }
731 
732 uint8_t
733 libusb20_dev_get_power_mode(struct libusb20_device *pdev)
734 {
735 	int error;
736 	uint8_t power_mode;
737 
738 	error = pdev->methods->get_power_mode(pdev, &power_mode);
739 	if (error)
740 		power_mode = LIBUSB20_POWER_ON;	/* fake power mode */
741 	return (power_mode);
742 }
743 
744 int
745 libusb20_dev_get_port_path(struct libusb20_device *pdev, uint8_t *buf, uint8_t bufsize)
746 {
747 
748 	if (pdev->port_level == 0) {
749 		/*
750 		 * Fallback for backends without port path:
751 		 */
752 		if (bufsize < 2)
753 			return (LIBUSB20_ERROR_OVERFLOW);
754 		buf[0] = pdev->parent_address;
755 		buf[1] = pdev->parent_port;
756 		return (2);
757 	}
758 
759 	/* check if client buffer is too small */
760 	if (pdev->port_level > bufsize)
761 		return (LIBUSB20_ERROR_OVERFLOW);
762 
763 	/* copy port number information */
764 	memcpy(buf, pdev->port_path, pdev->port_level);
765 
766 	return (pdev->port_level);	/* success */
767 }
768 
769 uint16_t
770 libusb20_dev_get_power_usage(struct libusb20_device *pdev)
771 {
772 	int error;
773 	uint16_t power_usage;
774 
775 	error = pdev->methods->get_power_usage(pdev, &power_usage);
776 	if (error)
777 		power_usage = 0;
778 	return (power_usage);
779 }
780 
781 int
782 libusb20_dev_set_alt_index(struct libusb20_device *pdev, uint8_t ifaceIndex, uint8_t altIndex)
783 {
784 	int error;
785 
786 	error = pdev->methods->set_alt_index(pdev, ifaceIndex, altIndex);
787 	return (error);
788 }
789 
790 int
791 libusb20_dev_set_config_index(struct libusb20_device *pdev, uint8_t configIndex)
792 {
793 	int error;
794 
795 	error = pdev->methods->set_config_index(pdev, configIndex);
796 	return (error);
797 }
798 
799 int
800 libusb20_dev_request_sync(struct libusb20_device *pdev,
801     struct LIBUSB20_CONTROL_SETUP_DECODED *setup, void *data,
802     uint16_t *pactlen, uint32_t timeout, uint8_t flags)
803 {
804 	int error;
805 
806 	error = pdev->methods->do_request_sync(pdev,
807 	    setup, data, pactlen, timeout, flags);
808 	return (error);
809 }
810 
811 int
812 libusb20_dev_req_string_sync(struct libusb20_device *pdev,
813     uint8_t str_index, uint16_t langid, void *ptr, uint16_t len)
814 {
815 	struct LIBUSB20_CONTROL_SETUP_DECODED req;
816 	int error;
817 	int flags;
818 
819 	/* make sure memory is initialised */
820 	memset(ptr, 0, len);
821 
822 	if (len < 4) {
823 		/* invalid length */
824 		return (LIBUSB20_ERROR_INVALID_PARAM);
825 	}
826 	LIBUSB20_INIT(LIBUSB20_CONTROL_SETUP, &req);
827 
828 	/*
829 	 * We need to read the USB string in two steps else some USB
830 	 * devices will complain.
831 	 */
832 	req.bmRequestType =
833 	    LIBUSB20_REQUEST_TYPE_STANDARD |
834 	    LIBUSB20_RECIPIENT_DEVICE |
835 	    LIBUSB20_ENDPOINT_IN;
836 	req.bRequest = LIBUSB20_REQUEST_GET_DESCRIPTOR;
837 	req.wValue = (LIBUSB20_DT_STRING << 8) | str_index;
838 	req.wIndex = langid;
839 	req.wLength = 4;		/* bytes */
840 
841 	error = libusb20_dev_request_sync(pdev, &req,
842 	    ptr, NULL, 1000, LIBUSB20_TRANSFER_SINGLE_SHORT_NOT_OK);
843 	if (error) {
844 		/* try to request full string */
845 		req.wLength = 255;
846 		flags = 0;
847 	} else {
848 		/* extract length and request full string */
849 		req.wLength = *(uint8_t *)ptr;
850 		flags = LIBUSB20_TRANSFER_SINGLE_SHORT_NOT_OK;
851 	}
852 	if (req.wLength > len) {
853 		/* partial string read */
854 		req.wLength = len;
855 	}
856 	error = libusb20_dev_request_sync(pdev, &req, ptr, NULL, 1000, flags);
857 	if (error)
858 		return (error);
859 
860 	if (((uint8_t *)ptr)[1] != LIBUSB20_DT_STRING)
861 		return (LIBUSB20_ERROR_OTHER);
862 	return (0);			/* success */
863 }
864 
865 int
866 libusb20_dev_req_string_simple_sync(struct libusb20_device *pdev,
867     uint8_t str_index, void *ptr, uint16_t len)
868 {
869 	char *buf;
870 	int error;
871 	uint16_t langid;
872 	uint16_t n;
873 	uint16_t i;
874 	uint16_t c;
875 	uint8_t temp[255];
876 	uint8_t swap;
877 
878 	/* the following code derives from the FreeBSD USB kernel */
879 
880 	if ((len < 1) || (ptr == NULL)) {
881 		/* too short buffer */
882 		return (LIBUSB20_ERROR_INVALID_PARAM);
883 	}
884 	error = libusb20_dev_req_string_sync(pdev,
885 	    0, 0, temp, sizeof(temp));
886 	if (error < 0) {
887 		*(uint8_t *)ptr = 0;	/* zero terminate */
888 		return (error);
889 	}
890 	langid = temp[2] | (temp[3] << 8);
891 
892 	error = libusb20_dev_req_string_sync(pdev, str_index,
893 	    langid, temp, sizeof(temp));
894 	if (error < 0) {
895 		*(uint8_t *)ptr = 0;	/* zero terminate */
896 		return (error);
897 	}
898 	if (temp[0] < 2) {
899 		/* string length is too short */
900 		*(uint8_t *)ptr = 0;	/* zero terminate */
901 		return (LIBUSB20_ERROR_OTHER);
902 	}
903 	/* reserve one byte for terminating zero */
904 	len--;
905 
906 	/* find maximum length */
907 	n = (temp[0] / 2) - 1;
908 	if (n > len) {
909 		n = len;
910 	}
911 	/* reset swap state */
912 	swap = 3;
913 
914 	/* setup output buffer pointer */
915 	buf = ptr;
916 
917 	/* convert and filter */
918 	for (i = 0; (i != n); i++) {
919 		c = temp[(2 * i) + 2] | (temp[(2 * i) + 3] << 8);
920 
921 		/* convert from Unicode, handle buggy strings */
922 		if (((c & 0xff00) == 0) && (swap & 1)) {
923 			/* Little Endian, default */
924 			*buf = c;
925 			swap = 1;
926 		} else if (((c & 0x00ff) == 0) && (swap & 2)) {
927 			/* Big Endian */
928 			*buf = c >> 8;
929 			swap = 2;
930 		} else {
931 			/* skip invalid character */
932 			continue;
933 		}
934 		/*
935 		 * Filter by default - we don't allow greater and less than
936 		 * signs because they might confuse the dmesg printouts!
937 		 */
938 		if ((*buf == '<') || (*buf == '>') || (!isprint(*buf))) {
939 			/* skip invalid character */
940 			continue;
941 		}
942 		buf++;
943 	}
944 	*buf = 0;			/* zero terminate string */
945 
946 	return (0);
947 }
948 
949 struct libusb20_config *
950 libusb20_dev_alloc_config(struct libusb20_device *pdev, uint8_t configIndex)
951 {
952 	struct libusb20_config *retval = NULL;
953 	uint8_t *ptr;
954 	uint16_t len;
955 	uint8_t do_close;
956 	int error;
957 
958 	/*
959 	 * Catch invalid configuration descriptor reads early on to
960 	 * avoid issues with devices that don't check for a valid USB
961 	 * configuration read request.
962 	 */
963 	if (configIndex >= pdev->ddesc.bNumConfigurations)
964 		return (NULL);
965 
966 	if (!pdev->is_opened) {
967 		error = libusb20_dev_open(pdev, 0);
968 		if (error) {
969 			return (NULL);
970 		}
971 		do_close = 1;
972 	} else {
973 		do_close = 0;
974 	}
975 	error = pdev->methods->get_config_desc_full(pdev,
976 	    &ptr, &len, configIndex);
977 
978 	if (error) {
979 		goto done;
980 	}
981 	/* parse new config descriptor */
982 	retval = libusb20_parse_config_desc(ptr);
983 
984 	/* free config descriptor */
985 	free(ptr);
986 
987 done:
988 	if (do_close) {
989 		error = libusb20_dev_close(pdev);
990 	}
991 	return (retval);
992 }
993 
994 struct libusb20_device *
995 libusb20_dev_alloc(void)
996 {
997 	struct libusb20_device *pdev;
998 
999 	pdev = malloc(sizeof(*pdev));
1000 	if (pdev == NULL) {
1001 		return (NULL);
1002 	}
1003 	memset(pdev, 0, sizeof(*pdev));
1004 
1005 	pdev->file = -1;
1006 	pdev->file_ctrl = -1;
1007 	pdev->methods = &libusb20_dummy_methods;
1008 	return (pdev);
1009 }
1010 
1011 uint8_t
1012 libusb20_dev_get_config_index(struct libusb20_device *pdev)
1013 {
1014 	int error;
1015 	uint8_t cfg_index;
1016 	uint8_t do_close;
1017 
1018 	if (!pdev->is_opened) {
1019 		error = libusb20_dev_open(pdev, 0);
1020 		if (error == 0) {
1021 			do_close = 1;
1022 		} else {
1023 			do_close = 0;
1024 		}
1025 	} else {
1026 		do_close = 0;
1027 	}
1028 
1029 	error = pdev->methods->get_config_index(pdev, &cfg_index);
1030 	if (error)
1031 		cfg_index = 0xFF;	/* current config index */
1032 	if (do_close) {
1033 		if (libusb20_dev_close(pdev)) {
1034 			/* ignore */
1035 		}
1036 	}
1037 	return (cfg_index);
1038 }
1039 
1040 uint8_t
1041 libusb20_dev_get_mode(struct libusb20_device *pdev)
1042 {
1043 	return (pdev->usb_mode);
1044 }
1045 
1046 uint8_t
1047 libusb20_dev_get_speed(struct libusb20_device *pdev)
1048 {
1049 	return (pdev->usb_speed);
1050 }
1051 
1052 /* if this function returns an error, the device is gone */
1053 int
1054 libusb20_dev_process(struct libusb20_device *pdev)
1055 {
1056 	int error;
1057 
1058 	error = pdev->methods->process(pdev);
1059 	return (error);
1060 }
1061 
1062 void
1063 libusb20_dev_wait_process(struct libusb20_device *pdev, int timeout)
1064 {
1065 	struct pollfd pfd[1];
1066 
1067 	if (!pdev->is_opened) {
1068 		return;
1069 	}
1070 	pfd[0].fd = pdev->file;
1071 	pfd[0].events = (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM);
1072 	pfd[0].revents = 0;
1073 
1074 	if (poll(pfd, 1, timeout)) {
1075 		/* ignore any error */
1076 	}
1077 	return;
1078 }
1079 
1080 void
1081 libusb20_dev_free(struct libusb20_device *pdev)
1082 {
1083 	if (pdev == NULL) {
1084 		/* be NULL safe */
1085 		return;
1086 	}
1087 	if (pdev->is_opened) {
1088 		if (libusb20_dev_close(pdev)) {
1089 			/* ignore any errors */
1090 		}
1091 	}
1092 	free(pdev);
1093 	return;
1094 }
1095 
1096 int
1097 libusb20_dev_get_info(struct libusb20_device *pdev,
1098     struct usb_device_info *pinfo)
1099 {
1100 	if (pinfo == NULL)
1101 		return (LIBUSB20_ERROR_INVALID_PARAM);
1102 
1103 	return (pdev->beMethods->dev_get_info(pdev, pinfo));
1104 }
1105 
1106 const char *
1107 libusb20_dev_get_backend_name(struct libusb20_device *pdev)
1108 {
1109 	return (pdev->beMethods->get_backend_name());
1110 }
1111 
1112 const char *
1113 libusb20_dev_get_desc(struct libusb20_device *pdev)
1114 {
1115 	return (pdev->usb_desc);
1116 }
1117 
1118 void
1119 libusb20_dev_set_debug(struct libusb20_device *pdev, int debug)
1120 {
1121 	pdev->debug = debug;
1122 	return;
1123 }
1124 
1125 int
1126 libusb20_dev_get_debug(struct libusb20_device *pdev)
1127 {
1128 	return (pdev->debug);
1129 }
1130 
1131 uint8_t
1132 libusb20_dev_get_address(struct libusb20_device *pdev)
1133 {
1134 	return (pdev->device_address);
1135 }
1136 
1137 uint8_t
1138 libusb20_dev_get_parent_address(struct libusb20_device *pdev)
1139 {
1140 	return (pdev->parent_address);
1141 }
1142 
1143 uint8_t
1144 libusb20_dev_get_parent_port(struct libusb20_device *pdev)
1145 {
1146 	return (pdev->parent_port);
1147 }
1148 
1149 uint8_t
1150 libusb20_dev_get_bus_number(struct libusb20_device *pdev)
1151 {
1152 	return (pdev->bus_number);
1153 }
1154 
1155 int
1156 libusb20_dev_get_iface_desc(struct libusb20_device *pdev,
1157     uint8_t iface_index, char *buf, uint8_t len)
1158 {
1159 	if ((buf == NULL) || (len == 0))
1160 		return (LIBUSB20_ERROR_INVALID_PARAM);
1161 
1162 	buf[0] = 0;		/* set default string value */
1163 
1164 	return (pdev->beMethods->dev_get_iface_desc(
1165 	    pdev, iface_index, buf, len));
1166 }
1167 
1168 /* USB backend operations */
1169 
1170 int
1171 libusb20_be_get_dev_quirk(struct libusb20_backend *pbe,
1172     uint16_t quirk_index, struct libusb20_quirk *pq)
1173 {
1174 	return (pbe->methods->root_get_dev_quirk(pbe, quirk_index, pq));
1175 }
1176 
1177 int
1178 libusb20_be_get_quirk_name(struct libusb20_backend *pbe,
1179     uint16_t quirk_index, struct libusb20_quirk *pq)
1180 {
1181 	return (pbe->methods->root_get_quirk_name(pbe, quirk_index, pq));
1182 }
1183 
1184 int
1185 libusb20_be_add_dev_quirk(struct libusb20_backend *pbe,
1186     struct libusb20_quirk *pq)
1187 {
1188 	return (pbe->methods->root_add_dev_quirk(pbe, pq));
1189 }
1190 
1191 int
1192 libusb20_be_remove_dev_quirk(struct libusb20_backend *pbe,
1193     struct libusb20_quirk *pq)
1194 {
1195 	return (pbe->methods->root_remove_dev_quirk(pbe, pq));
1196 }
1197 
1198 int
1199 libusb20_be_set_template(struct libusb20_backend *pbe, int temp)
1200 {
1201 	return (pbe->methods->root_set_template(pbe, temp));
1202 }
1203 
1204 int
1205 libusb20_be_get_template(struct libusb20_backend *pbe, int *ptemp)
1206 {
1207 	int temp;
1208 
1209 	if (ptemp == NULL)
1210 		ptemp = &temp;
1211 
1212 	return (pbe->methods->root_get_template(pbe, ptemp));
1213 }
1214 
1215 struct libusb20_device *
1216 libusb20_be_device_foreach(struct libusb20_backend *pbe, struct libusb20_device *pdev)
1217 {
1218 	if (pbe == NULL) {
1219 		pdev = NULL;
1220 	} else if (pdev == NULL) {
1221 		pdev = TAILQ_FIRST(&(pbe->usb_devs));
1222 	} else {
1223 		pdev = TAILQ_NEXT(pdev, dev_entry);
1224 	}
1225 	return (pdev);
1226 }
1227 
1228 struct libusb20_backend *
1229 libusb20_be_alloc(const struct libusb20_backend_methods *methods)
1230 {
1231 	struct libusb20_backend *pbe;
1232 
1233 	pbe = malloc(sizeof(*pbe));
1234 	if (pbe == NULL) {
1235 		return (NULL);
1236 	}
1237 	memset(pbe, 0, sizeof(*pbe));
1238 
1239 	TAILQ_INIT(&(pbe->usb_devs));
1240 
1241 	pbe->methods = methods;		/* set backend methods */
1242 
1243 	/* do the initial device scan */
1244 	if (pbe->methods->init_backend) {
1245 		pbe->methods->init_backend(pbe);
1246 	}
1247 	return (pbe);
1248 }
1249 
1250 struct libusb20_backend *
1251 libusb20_be_alloc_linux(void)
1252 {
1253 	return (NULL);
1254 }
1255 
1256 struct libusb20_backend *
1257 libusb20_be_alloc_ugen20(void)
1258 {
1259 	return (libusb20_be_alloc(&libusb20_ugen20_backend));
1260 }
1261 
1262 struct libusb20_backend *
1263 libusb20_be_alloc_default(void)
1264 {
1265 	struct libusb20_backend *pbe;
1266 
1267 #ifdef __linux__
1268 	pbe = libusb20_be_alloc_linux();
1269 	if (pbe) {
1270 		return (pbe);
1271 	}
1272 #endif
1273 	pbe = libusb20_be_alloc_ugen20();
1274 	if (pbe) {
1275 		return (pbe);
1276 	}
1277 	return (NULL);			/* no backend found */
1278 }
1279 
1280 void
1281 libusb20_be_free(struct libusb20_backend *pbe)
1282 {
1283 	struct libusb20_device *pdev;
1284 
1285 	if (pbe == NULL) {
1286 		/* be NULL safe */
1287 		return;
1288 	}
1289 	while ((pdev = libusb20_be_device_foreach(pbe, NULL))) {
1290 		libusb20_be_dequeue_device(pbe, pdev);
1291 		libusb20_dev_free(pdev);
1292 	}
1293 	if (pbe->methods->exit_backend) {
1294 		pbe->methods->exit_backend(pbe);
1295 	}
1296 	/* free backend */
1297 	free(pbe);
1298 }
1299 
1300 void
1301 libusb20_be_enqueue_device(struct libusb20_backend *pbe, struct libusb20_device *pdev)
1302 {
1303 	pdev->beMethods = pbe->methods;	/* copy backend methods */
1304 	TAILQ_INSERT_TAIL(&(pbe->usb_devs), pdev, dev_entry);
1305 }
1306 
1307 void
1308 libusb20_be_dequeue_device(struct libusb20_backend *pbe,
1309     struct libusb20_device *pdev)
1310 {
1311 	TAILQ_REMOVE(&(pbe->usb_devs), pdev, dev_entry);
1312 }
1313 
1314 const char *
1315 libusb20_strerror(int code)
1316 {
1317 	switch (code) {
1318 	case LIBUSB20_SUCCESS:
1319 		return ("Success");
1320 	case LIBUSB20_ERROR_IO:
1321 		return ("I/O error");
1322 	case LIBUSB20_ERROR_INVALID_PARAM:
1323 		return ("Invalid parameter");
1324 	case LIBUSB20_ERROR_ACCESS:
1325 		return ("Permissions error");
1326 	case LIBUSB20_ERROR_NO_DEVICE:
1327 		return ("No device");
1328 	case LIBUSB20_ERROR_NOT_FOUND:
1329 		return ("Not found");
1330 	case LIBUSB20_ERROR_BUSY:
1331 		return ("Device busy");
1332 	case LIBUSB20_ERROR_TIMEOUT:
1333 		return ("Timeout");
1334 	case LIBUSB20_ERROR_OVERFLOW:
1335 		return ("Overflow");
1336 	case LIBUSB20_ERROR_PIPE:
1337 		return ("Pipe error");
1338 	case LIBUSB20_ERROR_INTERRUPTED:
1339 		return ("Interrupted");
1340 	case LIBUSB20_ERROR_NO_MEM:
1341 		return ("Out of memory");
1342 	case LIBUSB20_ERROR_NOT_SUPPORTED:
1343 		return ("Not supported");
1344 	case LIBUSB20_ERROR_OTHER:
1345 		return ("Other error");
1346 	default:
1347 		return ("Unknown error");
1348 	}
1349 }
1350 
1351 const char *
1352 libusb20_error_name(int code)
1353 {
1354 	switch (code) {
1355 	case LIBUSB20_SUCCESS:
1356 		return ("LIBUSB20_SUCCESS");
1357 	case LIBUSB20_ERROR_IO:
1358 		return ("LIBUSB20_ERROR_IO");
1359 	case LIBUSB20_ERROR_INVALID_PARAM:
1360 		return ("LIBUSB20_ERROR_INVALID_PARAM");
1361 	case LIBUSB20_ERROR_ACCESS:
1362 		return ("LIBUSB20_ERROR_ACCESS");
1363 	case LIBUSB20_ERROR_NO_DEVICE:
1364 		return ("LIBUSB20_ERROR_NO_DEVICE");
1365 	case LIBUSB20_ERROR_NOT_FOUND:
1366 		return ("LIBUSB20_ERROR_NOT_FOUND");
1367 	case LIBUSB20_ERROR_BUSY:
1368 		return ("LIBUSB20_ERROR_BUSY");
1369 	case LIBUSB20_ERROR_TIMEOUT:
1370 		return ("LIBUSB20_ERROR_TIMEOUT");
1371 	case LIBUSB20_ERROR_OVERFLOW:
1372 		return ("LIBUSB20_ERROR_OVERFLOW");
1373 	case LIBUSB20_ERROR_PIPE:
1374 		return ("LIBUSB20_ERROR_PIPE");
1375 	case LIBUSB20_ERROR_INTERRUPTED:
1376 		return ("LIBUSB20_ERROR_INTERRUPTED");
1377 	case LIBUSB20_ERROR_NO_MEM:
1378 		return ("LIBUSB20_ERROR_NO_MEM");
1379 	case LIBUSB20_ERROR_NOT_SUPPORTED:
1380 		return ("LIBUSB20_ERROR_NOT_SUPPORTED");
1381 	case LIBUSB20_ERROR_OTHER:
1382 		return ("LIBUSB20_ERROR_OTHER");
1383 	default:
1384 		return ("LIBUSB20_ERROR_UNKNOWN");
1385 	}
1386 }
1387