xref: /freebsd/lib/libusb/libusb20.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2008-2009 Hans Petter Selasky. All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #ifdef LIBUSB_GLOBAL_INCLUDE_FILE
29 #include LIBUSB_GLOBAL_INCLUDE_FILE
30 #else
31 #include <ctype.h>
32 #include <poll.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <time.h>
37 #include <sys/queue.h>
38 #endif
39 
40 #include "libusb20.h"
41 #include "libusb20_desc.h"
42 #include "libusb20_int.h"
43 
44 static int
45 dummy_int(void)
46 {
47 	return (LIBUSB20_ERROR_NOT_SUPPORTED);
48 }
49 
50 static void
51 dummy_void(void)
52 {
53 	return;
54 }
55 
56 static void
57 dummy_callback(struct libusb20_transfer *xfer)
58 {
59 	;				/* style fix */
60 	switch (libusb20_tr_get_status(xfer)) {
61 	case LIBUSB20_TRANSFER_START:
62 		libusb20_tr_submit(xfer);
63 		break;
64 	default:
65 		/* complete or error */
66 		break;
67 	}
68 	return;
69 }
70 
71 #define	dummy_get_config_desc_full (void *)dummy_int
72 #define	dummy_get_config_index (void *)dummy_int
73 #define	dummy_set_config_index (void *)dummy_int
74 #define	dummy_set_alt_index (void *)dummy_int
75 #define	dummy_reset_device (void *)dummy_int
76 #define	dummy_check_connected (void *)dummy_int
77 #define	dummy_set_power_mode (void *)dummy_int
78 #define	dummy_get_power_mode (void *)dummy_int
79 #define	dummy_get_power_usage (void *)dummy_int
80 #define	dummy_get_stats (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] = 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] = 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] = 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] = 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] = 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] = 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 	 * Make sure libusb20_tr_get_pointer() fails:
612 	 */
613 	pdev->nTransfer = 0;
614 
615 	/*
616 	 * The following variable is only used by the libusb v0.1
617 	 * compat layer:
618 	 */
619 	pdev->claimed_interface = 0;
620 
621 	/*
622 	 * The following variable is only used by the libusb v1.0
623 	 * compat layer:
624 	 */
625 	pdev->auto_detach = 0;
626 
627 	return (error);
628 }
629 
630 int
631 libusb20_dev_detach_kernel_driver(struct libusb20_device *pdev, uint8_t ifaceIndex)
632 {
633 	int error;
634 
635 	error = pdev->methods->detach_kernel_driver(pdev, ifaceIndex);
636 	return (error);
637 }
638 
639 struct LIBUSB20_DEVICE_DESC_DECODED *
640 libusb20_dev_get_device_desc(struct libusb20_device *pdev)
641 {
642 	return (&(pdev->ddesc));
643 }
644 
645 int
646 libusb20_dev_get_fd(struct libusb20_device *pdev)
647 {
648 	return (pdev->file);
649 }
650 
651 int
652 libusb20_dev_kernel_driver_active(struct libusb20_device *pdev, uint8_t ifaceIndex)
653 {
654 	int error;
655 
656 	error = pdev->methods->kernel_driver_active(pdev, ifaceIndex);
657 	return (error);
658 }
659 
660 int
661 libusb20_dev_open(struct libusb20_device *pdev, uint16_t nTransferMax)
662 {
663 	struct libusb20_transfer *xfer;
664 	uint32_t size;
665 	uint16_t x;
666 	int error;
667 
668 	if (pdev->is_opened) {
669 		return (LIBUSB20_ERROR_BUSY);
670 	}
671 	if (nTransferMax >= 256) {
672 		return (LIBUSB20_ERROR_INVALID_PARAM);
673 	} else if (nTransferMax != 0) {
674 		size = sizeof(pdev->pTransfer[0]) * nTransferMax;
675 		pdev->pTransfer = malloc(size);
676 		if (pdev->pTransfer == NULL) {
677 			return (LIBUSB20_ERROR_NO_MEM);
678 		}
679 		memset(pdev->pTransfer, 0, size);
680 	}
681 	/* initialise all transfers */
682 	for (x = 0; x != nTransferMax; x++) {
683 
684 		xfer = pdev->pTransfer + x;
685 
686 		xfer->pdev = pdev;
687 		xfer->trIndex = x;
688 		xfer->callback = &dummy_callback;
689 	}
690 
691 	/* set "nTransfer" early */
692 	pdev->nTransfer = nTransferMax;
693 
694 	error = pdev->beMethods->open_device(pdev, nTransferMax);
695 
696 	if (error) {
697 		if (pdev->pTransfer != NULL) {
698 			free(pdev->pTransfer);
699 			pdev->pTransfer = NULL;
700 		}
701 		pdev->file = -1;
702 		pdev->file_ctrl = -1;
703 		pdev->nTransfer = 0;
704 	} else {
705 		pdev->is_opened = 1;
706 	}
707 	return (error);
708 }
709 
710 int
711 libusb20_dev_reset(struct libusb20_device *pdev)
712 {
713 	int error;
714 
715 	error = pdev->methods->reset_device(pdev);
716 	return (error);
717 }
718 
719 int
720 libusb20_dev_check_connected(struct libusb20_device *pdev)
721 {
722 	int error;
723 
724 	error = pdev->methods->check_connected(pdev);
725 	return (error);
726 }
727 
728 int
729 libusb20_dev_set_power_mode(struct libusb20_device *pdev, uint8_t power_mode)
730 {
731 	int error;
732 
733 	error = pdev->methods->set_power_mode(pdev, power_mode);
734 	return (error);
735 }
736 
737 uint8_t
738 libusb20_dev_get_power_mode(struct libusb20_device *pdev)
739 {
740 	int error;
741 	uint8_t power_mode;
742 
743 	error = pdev->methods->get_power_mode(pdev, &power_mode);
744 	if (error)
745 		power_mode = LIBUSB20_POWER_ON;	/* fake power mode */
746 	return (power_mode);
747 }
748 
749 int
750 libusb20_dev_get_port_path(struct libusb20_device *pdev, uint8_t *buf, uint8_t bufsize)
751 {
752 
753 	if (pdev->port_level == 0) {
754 		/*
755 		 * Fallback for backends without port path:
756 		 */
757 		if (bufsize < 2)
758 			return (LIBUSB20_ERROR_OVERFLOW);
759 		buf[0] = pdev->parent_address;
760 		buf[1] = pdev->parent_port;
761 		return (2);
762 	}
763 
764 	/* check if client buffer is too small */
765 	if (pdev->port_level > bufsize)
766 		return (LIBUSB20_ERROR_OVERFLOW);
767 
768 	/* copy port number information */
769 	memcpy(buf, pdev->port_path, pdev->port_level);
770 
771 	return (pdev->port_level);	/* success */
772 }
773 
774 uint16_t
775 libusb20_dev_get_power_usage(struct libusb20_device *pdev)
776 {
777 	int error;
778 	uint16_t power_usage;
779 
780 	error = pdev->methods->get_power_usage(pdev, &power_usage);
781 	if (error)
782 		power_usage = 0;
783 	return (power_usage);
784 }
785 
786 int
787 libusb20_dev_set_alt_index(struct libusb20_device *pdev, uint8_t ifaceIndex, uint8_t altIndex)
788 {
789 	int error;
790 
791 	error = pdev->methods->set_alt_index(pdev, ifaceIndex, altIndex);
792 	return (error);
793 }
794 
795 int
796 libusb20_dev_set_config_index(struct libusb20_device *pdev, uint8_t configIndex)
797 {
798 	int error;
799 
800 	error = pdev->methods->set_config_index(pdev, configIndex);
801 	return (error);
802 }
803 
804 int
805 libusb20_dev_request_sync(struct libusb20_device *pdev,
806     struct LIBUSB20_CONTROL_SETUP_DECODED *setup, void *data,
807     uint16_t *pactlen, uint32_t timeout, uint8_t flags)
808 {
809 	int error;
810 
811 	error = pdev->methods->do_request_sync(pdev,
812 	    setup, data, pactlen, timeout, flags);
813 	return (error);
814 }
815 
816 int
817 libusb20_dev_req_string_sync(struct libusb20_device *pdev,
818     uint8_t str_index, uint16_t langid, void *ptr, uint16_t len)
819 {
820 	struct LIBUSB20_CONTROL_SETUP_DECODED req;
821 	int error;
822 	int flags;
823 
824 	/* make sure memory is initialised */
825 	memset(ptr, 0, len);
826 
827 	if (len < 4) {
828 		/* invalid length */
829 		return (LIBUSB20_ERROR_INVALID_PARAM);
830 	}
831 	LIBUSB20_INIT(LIBUSB20_CONTROL_SETUP, &req);
832 
833 	/*
834 	 * We need to read the USB string in two steps else some USB
835 	 * devices will complain.
836 	 */
837 	req.bmRequestType =
838 	    LIBUSB20_REQUEST_TYPE_STANDARD |
839 	    LIBUSB20_RECIPIENT_DEVICE |
840 	    LIBUSB20_ENDPOINT_IN;
841 	req.bRequest = LIBUSB20_REQUEST_GET_DESCRIPTOR;
842 	req.wValue = (LIBUSB20_DT_STRING << 8) | str_index;
843 	req.wIndex = langid;
844 	req.wLength = 4;		/* bytes */
845 
846 	error = libusb20_dev_request_sync(pdev, &req,
847 	    ptr, NULL, 1000, LIBUSB20_TRANSFER_SINGLE_SHORT_NOT_OK);
848 	if (error) {
849 		/* try to request full string */
850 		req.wLength = 255;
851 		flags = 0;
852 	} else {
853 		/* extract length and request full string */
854 		req.wLength = *(uint8_t *)ptr;
855 		flags = LIBUSB20_TRANSFER_SINGLE_SHORT_NOT_OK;
856 	}
857 	if (req.wLength > len) {
858 		/* partial string read */
859 		req.wLength = len;
860 	}
861 	error = libusb20_dev_request_sync(pdev, &req, ptr, NULL, 1000, flags);
862 	if (error)
863 		return (error);
864 
865 	if (((uint8_t *)ptr)[1] != LIBUSB20_DT_STRING)
866 		return (LIBUSB20_ERROR_OTHER);
867 	return (0);			/* success */
868 }
869 
870 int
871 libusb20_dev_req_string_simple_sync(struct libusb20_device *pdev,
872     uint8_t str_index, void *ptr, uint16_t len)
873 {
874 	char *buf;
875 	int error;
876 	uint16_t langid;
877 	uint16_t n;
878 	uint16_t i;
879 	uint16_t c;
880 	uint8_t temp[255];
881 	uint8_t swap;
882 
883 	/* the following code derives from the FreeBSD USB kernel */
884 
885 	if ((len < 1) || (ptr == NULL)) {
886 		/* too short buffer */
887 		return (LIBUSB20_ERROR_INVALID_PARAM);
888 	}
889 	error = libusb20_dev_req_string_sync(pdev,
890 	    0, 0, temp, sizeof(temp));
891 	if (error < 0) {
892 		*(uint8_t *)ptr = 0;	/* zero terminate */
893 		return (error);
894 	}
895 	langid = temp[2] | (temp[3] << 8);
896 
897 	error = libusb20_dev_req_string_sync(pdev, str_index,
898 	    langid, temp, sizeof(temp));
899 	if (error < 0) {
900 		*(uint8_t *)ptr = 0;	/* zero terminate */
901 		return (error);
902 	}
903 	if (temp[0] < 2) {
904 		/* string length is too short */
905 		*(uint8_t *)ptr = 0;	/* zero terminate */
906 		return (LIBUSB20_ERROR_OTHER);
907 	}
908 	/* reserve one byte for terminating zero */
909 	len--;
910 
911 	/* find maximum length */
912 	n = (temp[0] / 2) - 1;
913 	if (n > len) {
914 		n = len;
915 	}
916 	/* reset swap state */
917 	swap = 3;
918 
919 	/* setup output buffer pointer */
920 	buf = ptr;
921 
922 	/* convert and filter */
923 	for (i = 0; (i != n); i++) {
924 		c = temp[(2 * i) + 2] | (temp[(2 * i) + 3] << 8);
925 
926 		/* convert from Unicode, handle buggy strings */
927 		if (((c & 0xff00) == 0) && (swap & 1)) {
928 			/* Little Endian, default */
929 			*buf = c;
930 			swap = 1;
931 		} else if (((c & 0x00ff) == 0) && (swap & 2)) {
932 			/* Big Endian */
933 			*buf = c >> 8;
934 			swap = 2;
935 		} else {
936 			/* skip invalid character */
937 			continue;
938 		}
939 		/*
940 		 * Filter by default - we don't allow greater and less than
941 		 * signs because they might confuse the dmesg printouts!
942 		 */
943 		if ((*buf == '<') || (*buf == '>') || (!isprint(*buf))) {
944 			/* skip invalid character */
945 			continue;
946 		}
947 		buf++;
948 	}
949 	*buf = 0;			/* zero terminate string */
950 
951 	return (0);
952 }
953 
954 struct libusb20_config *
955 libusb20_dev_alloc_config(struct libusb20_device *pdev, uint8_t configIndex)
956 {
957 	struct libusb20_config *retval = NULL;
958 	uint8_t *ptr;
959 	uint16_t len;
960 	uint8_t do_close;
961 	int error;
962 
963 	/*
964 	 * Catch invalid configuration descriptor reads early on to
965 	 * avoid issues with devices that don't check for a valid USB
966 	 * configuration read request.
967 	 */
968 	if (configIndex >= pdev->ddesc.bNumConfigurations)
969 		return (NULL);
970 
971 	if (!pdev->is_opened) {
972 		error = libusb20_dev_open(pdev, 0);
973 		if (error) {
974 			return (NULL);
975 		}
976 		do_close = 1;
977 	} else {
978 		do_close = 0;
979 	}
980 	error = pdev->methods->get_config_desc_full(pdev,
981 	    &ptr, &len, configIndex);
982 
983 	if (error) {
984 		goto done;
985 	}
986 	/* parse new config descriptor */
987 	retval = libusb20_parse_config_desc(ptr);
988 
989 	/* free config descriptor */
990 	free(ptr);
991 
992 done:
993 	if (do_close) {
994 		error = libusb20_dev_close(pdev);
995 	}
996 	return (retval);
997 }
998 
999 struct libusb20_device *
1000 libusb20_dev_alloc(void)
1001 {
1002 	struct libusb20_device *pdev;
1003 
1004 	pdev = malloc(sizeof(*pdev));
1005 	if (pdev == NULL) {
1006 		return (NULL);
1007 	}
1008 	memset(pdev, 0, sizeof(*pdev));
1009 
1010 	pdev->file = -1;
1011 	pdev->file_ctrl = -1;
1012 	pdev->methods = &libusb20_dummy_methods;
1013 	return (pdev);
1014 }
1015 
1016 uint8_t
1017 libusb20_dev_get_config_index(struct libusb20_device *pdev)
1018 {
1019 	int error;
1020 	uint8_t cfg_index;
1021 	uint8_t do_close;
1022 
1023 	if (!pdev->is_opened) {
1024 		error = libusb20_dev_open(pdev, 0);
1025 		if (error == 0) {
1026 			do_close = 1;
1027 		} else {
1028 			do_close = 0;
1029 		}
1030 	} else {
1031 		do_close = 0;
1032 	}
1033 
1034 	error = pdev->methods->get_config_index(pdev, &cfg_index);
1035 	if (error)
1036 		cfg_index = 0xFF;	/* current config index */
1037 	if (do_close) {
1038 		if (libusb20_dev_close(pdev)) {
1039 			/* ignore */
1040 		}
1041 	}
1042 	return (cfg_index);
1043 }
1044 
1045 uint8_t
1046 libusb20_dev_get_mode(struct libusb20_device *pdev)
1047 {
1048 	return (pdev->usb_mode);
1049 }
1050 
1051 uint8_t
1052 libusb20_dev_get_speed(struct libusb20_device *pdev)
1053 {
1054 	return (pdev->usb_speed);
1055 }
1056 
1057 int
1058 libusb20_dev_get_stats(struct libusb20_device *pdev, struct libusb20_device_stats *pstats)
1059 {
1060 	uint8_t do_close;
1061 	int error;
1062 
1063 	if (!pdev->is_opened) {
1064 		error = libusb20_dev_open(pdev, 0);
1065 		if (error == 0) {
1066 			do_close = 1;
1067 		} else {
1068 			do_close = 0;
1069 		}
1070 	} else {
1071 		do_close = 0;
1072 	}
1073 
1074 	error = pdev->methods->get_stats(pdev, pstats);
1075 
1076 	if (do_close)
1077 		(void) libusb20_dev_close(pdev);
1078 
1079 	return (error);
1080 }
1081 
1082 /* if this function returns an error, the device is gone */
1083 int
1084 libusb20_dev_process(struct libusb20_device *pdev)
1085 {
1086 	int error;
1087 
1088 	error = pdev->methods->process(pdev);
1089 	return (error);
1090 }
1091 
1092 void
1093 libusb20_dev_wait_process(struct libusb20_device *pdev, int timeout)
1094 {
1095 	struct pollfd pfd[1];
1096 
1097 	if (!pdev->is_opened) {
1098 		return;
1099 	}
1100 	pfd[0].fd = pdev->file;
1101 	pfd[0].events = (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM);
1102 	pfd[0].revents = 0;
1103 
1104 	if (poll(pfd, 1, timeout)) {
1105 		/* ignore any error */
1106 	}
1107 	return;
1108 }
1109 
1110 void
1111 libusb20_dev_free(struct libusb20_device *pdev)
1112 {
1113 	if (pdev == NULL) {
1114 		/* be NULL safe */
1115 		return;
1116 	}
1117 	if (pdev->is_opened) {
1118 		if (libusb20_dev_close(pdev)) {
1119 			/* ignore any errors */
1120 		}
1121 	}
1122 	free(pdev);
1123 	return;
1124 }
1125 
1126 int
1127 libusb20_dev_get_info(struct libusb20_device *pdev,
1128     struct usb_device_info *pinfo)
1129 {
1130 	if (pinfo == NULL)
1131 		return (LIBUSB20_ERROR_INVALID_PARAM);
1132 
1133 	return (pdev->beMethods->dev_get_info(pdev, pinfo));
1134 }
1135 
1136 const char *
1137 libusb20_dev_get_backend_name(struct libusb20_device *pdev)
1138 {
1139 	return (pdev->beMethods->get_backend_name());
1140 }
1141 
1142 const char *
1143 libusb20_dev_get_desc(struct libusb20_device *pdev)
1144 {
1145 	return (pdev->usb_desc);
1146 }
1147 
1148 void
1149 libusb20_dev_set_debug(struct libusb20_device *pdev, int debug)
1150 {
1151 	pdev->debug = debug;
1152 	return;
1153 }
1154 
1155 int
1156 libusb20_dev_get_debug(struct libusb20_device *pdev)
1157 {
1158 	return (pdev->debug);
1159 }
1160 
1161 uint8_t
1162 libusb20_dev_get_address(struct libusb20_device *pdev)
1163 {
1164 	return (pdev->device_address);
1165 }
1166 
1167 uint8_t
1168 libusb20_dev_get_parent_address(struct libusb20_device *pdev)
1169 {
1170 	return (pdev->parent_address);
1171 }
1172 
1173 uint8_t
1174 libusb20_dev_get_parent_port(struct libusb20_device *pdev)
1175 {
1176 	return (pdev->parent_port);
1177 }
1178 
1179 uint8_t
1180 libusb20_dev_get_bus_number(struct libusb20_device *pdev)
1181 {
1182 	return (pdev->bus_number);
1183 }
1184 
1185 int
1186 libusb20_dev_get_iface_desc(struct libusb20_device *pdev,
1187     uint8_t iface_index, char *buf, uint8_t len)
1188 {
1189 	if ((buf == NULL) || (len == 0))
1190 		return (LIBUSB20_ERROR_INVALID_PARAM);
1191 
1192 	buf[0] = 0;		/* set default string value */
1193 
1194 	return (pdev->beMethods->dev_get_iface_desc(
1195 	    pdev, iface_index, buf, len));
1196 }
1197 
1198 /* USB backend operations */
1199 
1200 int
1201 libusb20_be_get_dev_quirk(struct libusb20_backend *pbe,
1202     uint16_t quirk_index, struct libusb20_quirk *pq)
1203 {
1204 	return (pbe->methods->root_get_dev_quirk(pbe, quirk_index, pq));
1205 }
1206 
1207 int
1208 libusb20_be_get_quirk_name(struct libusb20_backend *pbe,
1209     uint16_t quirk_index, struct libusb20_quirk *pq)
1210 {
1211 	return (pbe->methods->root_get_quirk_name(pbe, quirk_index, pq));
1212 }
1213 
1214 int
1215 libusb20_be_add_dev_quirk(struct libusb20_backend *pbe,
1216     struct libusb20_quirk *pq)
1217 {
1218 	return (pbe->methods->root_add_dev_quirk(pbe, pq));
1219 }
1220 
1221 int
1222 libusb20_be_remove_dev_quirk(struct libusb20_backend *pbe,
1223     struct libusb20_quirk *pq)
1224 {
1225 	return (pbe->methods->root_remove_dev_quirk(pbe, pq));
1226 }
1227 
1228 int
1229 libusb20_be_set_template(struct libusb20_backend *pbe, int temp)
1230 {
1231 	return (pbe->methods->root_set_template(pbe, temp));
1232 }
1233 
1234 int
1235 libusb20_be_get_template(struct libusb20_backend *pbe, int *ptemp)
1236 {
1237 	int temp;
1238 
1239 	if (ptemp == NULL)
1240 		ptemp = &temp;
1241 
1242 	return (pbe->methods->root_get_template(pbe, ptemp));
1243 }
1244 
1245 struct libusb20_device *
1246 libusb20_be_device_foreach(struct libusb20_backend *pbe, struct libusb20_device *pdev)
1247 {
1248 	if (pbe == NULL) {
1249 		pdev = NULL;
1250 	} else if (pdev == NULL) {
1251 		pdev = TAILQ_FIRST(&(pbe->usb_devs));
1252 	} else {
1253 		pdev = TAILQ_NEXT(pdev, dev_entry);
1254 	}
1255 	return (pdev);
1256 }
1257 
1258 struct libusb20_backend *
1259 libusb20_be_alloc(const struct libusb20_backend_methods *methods)
1260 {
1261 	struct libusb20_backend *pbe;
1262 
1263 	pbe = malloc(sizeof(*pbe));
1264 	if (pbe == NULL) {
1265 		return (NULL);
1266 	}
1267 	memset(pbe, 0, sizeof(*pbe));
1268 
1269 	TAILQ_INIT(&(pbe->usb_devs));
1270 
1271 	pbe->methods = methods;		/* set backend methods */
1272 
1273 	/* do the initial device scan */
1274 	if (pbe->methods->init_backend) {
1275 		pbe->methods->init_backend(pbe);
1276 	}
1277 	return (pbe);
1278 }
1279 
1280 struct libusb20_backend *
1281 libusb20_be_alloc_linux(void)
1282 {
1283 	return (NULL);
1284 }
1285 
1286 struct libusb20_backend *
1287 libusb20_be_alloc_ugen20(void)
1288 {
1289 	return (libusb20_be_alloc(&libusb20_ugen20_backend));
1290 }
1291 
1292 struct libusb20_backend *
1293 libusb20_be_alloc_default(void)
1294 {
1295 	struct libusb20_backend *pbe;
1296 
1297 #ifdef __linux__
1298 	pbe = libusb20_be_alloc_linux();
1299 	if (pbe) {
1300 		return (pbe);
1301 	}
1302 #endif
1303 	pbe = libusb20_be_alloc_ugen20();
1304 	if (pbe) {
1305 		return (pbe);
1306 	}
1307 	return (NULL);			/* no backend found */
1308 }
1309 
1310 void
1311 libusb20_be_free(struct libusb20_backend *pbe)
1312 {
1313 	struct libusb20_device *pdev;
1314 
1315 	if (pbe == NULL) {
1316 		/* be NULL safe */
1317 		return;
1318 	}
1319 	while ((pdev = libusb20_be_device_foreach(pbe, NULL))) {
1320 		libusb20_be_dequeue_device(pbe, pdev);
1321 		libusb20_dev_free(pdev);
1322 	}
1323 	if (pbe->methods->exit_backend) {
1324 		pbe->methods->exit_backend(pbe);
1325 	}
1326 	/* free backend */
1327 	free(pbe);
1328 }
1329 
1330 void
1331 libusb20_be_enqueue_device(struct libusb20_backend *pbe, struct libusb20_device *pdev)
1332 {
1333 	pdev->beMethods = pbe->methods;	/* copy backend methods */
1334 	TAILQ_INSERT_TAIL(&(pbe->usb_devs), pdev, dev_entry);
1335 }
1336 
1337 void
1338 libusb20_be_dequeue_device(struct libusb20_backend *pbe,
1339     struct libusb20_device *pdev)
1340 {
1341 	TAILQ_REMOVE(&(pbe->usb_devs), pdev, dev_entry);
1342 }
1343 
1344 const char *
1345 libusb20_strerror(int code)
1346 {
1347 	switch (code) {
1348 	case LIBUSB20_SUCCESS:
1349 		return ("Success");
1350 	case LIBUSB20_ERROR_IO:
1351 		return ("I/O error");
1352 	case LIBUSB20_ERROR_INVALID_PARAM:
1353 		return ("Invalid parameter");
1354 	case LIBUSB20_ERROR_ACCESS:
1355 		return ("Permissions error");
1356 	case LIBUSB20_ERROR_NO_DEVICE:
1357 		return ("No device");
1358 	case LIBUSB20_ERROR_NOT_FOUND:
1359 		return ("Not found");
1360 	case LIBUSB20_ERROR_BUSY:
1361 		return ("Device busy");
1362 	case LIBUSB20_ERROR_TIMEOUT:
1363 		return ("Timeout");
1364 	case LIBUSB20_ERROR_OVERFLOW:
1365 		return ("Overflow");
1366 	case LIBUSB20_ERROR_PIPE:
1367 		return ("Pipe error");
1368 	case LIBUSB20_ERROR_INTERRUPTED:
1369 		return ("Interrupted");
1370 	case LIBUSB20_ERROR_NO_MEM:
1371 		return ("Out of memory");
1372 	case LIBUSB20_ERROR_NOT_SUPPORTED:
1373 		return ("Not supported");
1374 	case LIBUSB20_ERROR_OTHER:
1375 		return ("Other error");
1376 	default:
1377 		return ("Unknown error");
1378 	}
1379 }
1380 
1381 const char *
1382 libusb20_error_name(int code)
1383 {
1384 	switch (code) {
1385 	case LIBUSB20_SUCCESS:
1386 		return ("LIBUSB20_SUCCESS");
1387 	case LIBUSB20_ERROR_IO:
1388 		return ("LIBUSB20_ERROR_IO");
1389 	case LIBUSB20_ERROR_INVALID_PARAM:
1390 		return ("LIBUSB20_ERROR_INVALID_PARAM");
1391 	case LIBUSB20_ERROR_ACCESS:
1392 		return ("LIBUSB20_ERROR_ACCESS");
1393 	case LIBUSB20_ERROR_NO_DEVICE:
1394 		return ("LIBUSB20_ERROR_NO_DEVICE");
1395 	case LIBUSB20_ERROR_NOT_FOUND:
1396 		return ("LIBUSB20_ERROR_NOT_FOUND");
1397 	case LIBUSB20_ERROR_BUSY:
1398 		return ("LIBUSB20_ERROR_BUSY");
1399 	case LIBUSB20_ERROR_TIMEOUT:
1400 		return ("LIBUSB20_ERROR_TIMEOUT");
1401 	case LIBUSB20_ERROR_OVERFLOW:
1402 		return ("LIBUSB20_ERROR_OVERFLOW");
1403 	case LIBUSB20_ERROR_PIPE:
1404 		return ("LIBUSB20_ERROR_PIPE");
1405 	case LIBUSB20_ERROR_INTERRUPTED:
1406 		return ("LIBUSB20_ERROR_INTERRUPTED");
1407 	case LIBUSB20_ERROR_NO_MEM:
1408 		return ("LIBUSB20_ERROR_NO_MEM");
1409 	case LIBUSB20_ERROR_NOT_SUPPORTED:
1410 		return ("LIBUSB20_ERROR_NOT_SUPPORTED");
1411 	case LIBUSB20_ERROR_OTHER:
1412 		return ("LIBUSB20_ERROR_OTHER");
1413 	default:
1414 		return ("LIBUSB20_ERROR_UNKNOWN");
1415 	}
1416 }
1417