xref: /netbsd-src/sys/dev/usb/uvideo.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: uvideo.c,v 1.46 2018/01/21 13:57:12 skrll Exp $	*/
2 
3 /*
4  * Copyright (c) 2008 Patrick Mahoney
5  * All rights reserved.
6  *
7  * This code was written by Patrick Mahoney (pat@polycrystal.org) as
8  * part of Google Summer of Code 2008.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * USB video specs:
41  *      http://www.usb.org/developers/devclass_docs/USB_Video_Class_1_1.zip
42  */
43 
44 #include <sys/cdefs.h>
45 __KERNEL_RCSID(0, "$NetBSD: uvideo.c,v 1.46 2018/01/21 13:57:12 skrll Exp $");
46 
47 #ifdef _KERNEL_OPT
48 #include "opt_usb.h"
49 #endif
50 
51 #ifdef _MODULE
52 #include <sys/module.h>
53 #endif
54 
55 #include <sys/param.h>
56 #include <sys/systm.h>
57 #include <sys/kernel.h>
58 #include <sys/kmem.h>
59 #include <sys/device.h>
60 #include <sys/ioctl.h>
61 #include <sys/uio.h>
62 #include <sys/file.h>
63 #include <sys/select.h>
64 #include <sys/proc.h>
65 #include <sys/conf.h>
66 #include <sys/vnode.h>
67 #include <sys/poll.h>
68 #include <sys/queue.h>	/* SLIST */
69 #include <sys/kthread.h>
70 #include <sys/bus.h>
71 
72 #include <sys/videoio.h>
73 #include <dev/video_if.h>
74 
75 #include <dev/usb/usb.h>
76 #include <dev/usb/usbdi.h>
77 #include <dev/usb/usbdivar.h>
78 #include <dev/usb/usbdi_util.h>
79 #include <dev/usb/usb_quirks.h>
80 
81 #include <dev/usb/uvideoreg.h>
82 
83 #define UVIDEO_NXFERS	3
84 #define PRI_UVIDEO	PRI_BIO
85 
86 /* #define UVIDEO_DISABLE_MJPEG */
87 
88 #ifdef UVIDEO_DEBUG
89 #define DPRINTF(x)	do { if (uvideodebug) printf x; } while (0)
90 #define DPRINTFN(n,x)	do { if (uvideodebug>(n)) printf x; } while (0)
91 int	uvideodebug = 20;
92 #else
93 #define DPRINTF(x)
94 #define DPRINTFN(n,x)
95 #endif
96 
97 typedef enum {
98 	UVIDEO_STATE_CLOSED,
99 	UVIDEO_STATE_OPENING,
100 	UVIDEO_STATE_IDLE
101 } uvideo_state;
102 
103 struct uvideo_camera_terminal {
104 	uint16_t	ct_objective_focal_min;
105 	uint16_t	ct_objective_focal_max;
106 	uint16_t	ct_ocular_focal_length;
107 };
108 
109 struct uvideo_processing_unit {
110 	uint16_t	pu_max_multiplier; /* digital zoom */
111 	uint8_t		pu_video_standards;
112 };
113 
114 struct uvideo_extension_unit {
115 	guid_t		xu_guid;
116 };
117 
118 /* For simplicity, we consider a Terminal a special case of Unit
119  * rather than a separate entity. */
120 struct uvideo_unit {
121 	uint8_t		vu_id;
122 	uint8_t		vu_type;
123 	uint8_t		vu_dst_id;
124 	uint8_t		vu_nsrcs;
125 	union {
126 		uint8_t	vu_src_id;	/* vu_nsrcs = 1 */
127 		uint8_t	*vu_src_id_ary; /* vu_nsrcs > 1 */
128 	} s;
129 
130 	/* fields for individual unit/terminal types */
131 	union {
132 		struct uvideo_camera_terminal	vu_camera;
133 		struct uvideo_processing_unit	vu_processing;
134 		struct uvideo_extension_unit	vu_extension;
135 	} u;
136 
137 	/* Used by camera terminal, processing and extention units. */
138 	uint8_t		vu_control_size; /* number of bytes in vu_controls */
139 	uint8_t		*vu_controls;	 /* array of bytes. bits are
140 					  * numbered from 0 at least
141 					  * significant bit to
142 					  * (8*vu_control_size - 1)*/
143 };
144 
145 struct uvideo_alternate {
146 	uint8_t		altno;
147 	uint8_t		interval;
148 	uint16_t	max_packet_size;
149 	SLIST_ENTRY(uvideo_alternate)	entries;
150 };
151 SLIST_HEAD(altlist, uvideo_alternate);
152 
153 #define UVIDEO_FORMAT_GET_FORMAT_INDEX(fmt)	\
154 	((fmt)->format.priv & 0xff)
155 #define UVIDEO_FORMAT_GET_FRAME_INDEX(fmt)	\
156 	(((fmt)->format.priv >> 8) & 0xff)
157 /* TODO: find a better way to set bytes within this 32 bit value? */
158 #define UVIDEO_FORMAT_SET_FORMAT_INDEX(fmt, index) do {	\
159 		(fmt)->format.priv &= ~0xff;		\
160 		(fmt)->format.priv |= ((index) & 0xff);	\
161 	} while (0)
162 #define UVIDEO_FORMAT_SET_FRAME_INDEX(fmt, index) do {			\
163 		(fmt)->format.priv &= ~(0xff << 8);			\
164 		((fmt)->format.priv |= (((index) & 0xff) << 8));	\
165 	} while (0)
166 
167 struct uvideo_pixel_format {
168 	enum video_pixel_format	pixel_format;
169 	SIMPLEQ_ENTRY(uvideo_pixel_format) entries;
170 };
171 SIMPLEQ_HEAD(uvideo_pixel_format_list, uvideo_pixel_format);
172 
173 struct uvideo_format {
174 	struct video_format	format;
175 	SIMPLEQ_ENTRY(uvideo_format) entries;
176 };
177 SIMPLEQ_HEAD(uvideo_format_list, uvideo_format);
178 
179 struct uvideo_isoc_xfer;
180 struct uvideo_stream;
181 
182 struct uvideo_isoc {
183 	struct uvideo_isoc_xfer	*i_ix;
184 	struct uvideo_stream	*i_vs;
185 	struct usbd_xfer	*i_xfer;
186 	uint8_t			*i_buf;
187 	uint16_t		*i_frlengths;
188 };
189 
190 struct uvideo_isoc_xfer {
191 	uint8_t			ix_endpt;
192 	struct usbd_pipe	*ix_pipe;
193 	struct uvideo_isoc	ix_i[UVIDEO_NXFERS];
194 	uint32_t		ix_nframes;
195 	uint32_t		ix_uframe_len;
196 
197 	struct altlist		ix_altlist;
198 };
199 
200 struct uvideo_bulk_xfer {
201 	uint8_t			bx_endpt;
202 	struct usbd_pipe	*bx_pipe;
203 	struct usbd_xfer	*bx_xfer;
204 	uint8_t			*bx_buffer;
205 	int			bx_buflen;
206 	bool			bx_running;
207 	kcondvar_t		bx_cv;
208 	kmutex_t		bx_lock;
209 };
210 
211 struct uvideo_stream {
212 	struct uvideo_softc	*vs_parent;
213 	struct usbd_interface	*vs_iface;
214 	uint8_t			vs_ifaceno;
215 	uint8_t			vs_subtype;  /* input or output */
216 	uint16_t		vs_probelen; /* length of probe and
217 					      * commit data; varies
218 					      * depending on version
219 					      * of spec. */
220 	struct uvideo_format_list vs_formats;
221 	struct uvideo_pixel_format_list vs_pixel_formats;
222 	struct video_format	*vs_default_format;
223 	struct video_format	vs_current_format;
224 
225 	/* usb transfer details */
226 	uint8_t			vs_xfer_type;
227 	union {
228 		struct uvideo_bulk_xfer	bulk;
229 		struct uvideo_isoc_xfer isoc;
230 	} vs_xfer;
231 
232 	int			vs_frameno;	/* toggles between 0 and 1 */
233 
234 	/* current video format */
235 	uint32_t		vs_max_payload_size;
236 	uint32_t		vs_frame_interval;
237 	SLIST_ENTRY(uvideo_stream) entries;
238 };
239 SLIST_HEAD(uvideo_stream_list, uvideo_stream);
240 
241 struct uvideo_softc {
242         device_t   	sc_dev;		/* base device */
243         struct usbd_device	*sc_udev;	/* device */
244 	struct usbd_interface	*sc_iface;	/* interface handle */
245         int     		sc_ifaceno;	/* interface number */
246 	char			*sc_devname;
247 
248 	device_t		sc_videodev;
249 
250 	int			sc_dying;
251 	uvideo_state		sc_state;
252 
253 	uint8_t			sc_nunits;
254 	struct uvideo_unit	**sc_unit;
255 
256 	struct uvideo_stream	*sc_stream_in;
257 
258 	struct uvideo_stream_list sc_stream_list;
259 
260 	char			sc_businfo[32];
261 };
262 
263 int	uvideo_match(device_t, cfdata_t, void *);
264 void	uvideo_attach(device_t, device_t, void *);
265 int	uvideo_detach(device_t, int);
266 void	uvideo_childdet(device_t, device_t);
267 int	uvideo_activate(device_t, enum devact);
268 
269 static int	uvideo_open(void *, int);
270 static void	uvideo_close(void *);
271 static const char * uvideo_get_devname(void *);
272 static const char * uvideo_get_businfo(void *);
273 
274 static int	uvideo_enum_format(void *, uint32_t, struct video_format *);
275 static int	uvideo_get_format(void *, struct video_format *);
276 static int	uvideo_set_format(void *, struct video_format *);
277 static int	uvideo_try_format(void *, struct video_format *);
278 static int	uvideo_start_transfer(void *);
279 static int	uvideo_stop_transfer(void *);
280 
281 static int	uvideo_get_control_group(void *,
282 					 struct video_control_group *);
283 static int	uvideo_set_control_group(void *,
284 					 const struct video_control_group *);
285 
286 static usbd_status	uvideo_init_control(
287 	struct uvideo_softc *,
288 	const usb_interface_descriptor_t *,
289 	usbd_desc_iter_t *);
290 static usbd_status	uvideo_init_collection(
291 	struct uvideo_softc *,
292 	const usb_interface_descriptor_t *,
293 	usbd_desc_iter_t *);
294 
295 /* Functions for unit & terminal descriptors */
296 static struct uvideo_unit *	uvideo_unit_alloc(const uvideo_descriptor_t *);
297 static usbd_status		uvideo_unit_init(struct uvideo_unit *,
298 						 const uvideo_descriptor_t *);
299 static void			uvideo_unit_free(struct uvideo_unit *);
300 static usbd_status		uvideo_unit_alloc_controls(struct uvideo_unit *,
301 							   uint8_t,
302 							   const uint8_t *);
303 static void			uvideo_unit_free_controls(struct uvideo_unit *);
304 static usbd_status		uvideo_unit_alloc_sources(struct uvideo_unit *,
305 							  uint8_t,
306 							  const uint8_t *);
307 static void			uvideo_unit_free_sources(struct uvideo_unit *);
308 
309 
310 
311 
312 /* Functions for uvideo_stream, primary unit associated with a video
313  * driver or device file. */
314 static struct uvideo_stream *	uvideo_find_stream(struct uvideo_softc *,
315 						   uint8_t);
316 #if 0
317 static struct uvideo_format *	uvideo_stream_find_format(
318 	struct uvideo_stream *,
319 	uint8_t, uint8_t);
320 #endif
321 static struct uvideo_format *	uvideo_stream_guess_format(
322 	struct uvideo_stream *,
323 	enum video_pixel_format, uint32_t, uint32_t);
324 static struct uvideo_stream *	uvideo_stream_alloc(void);
325 static usbd_status		uvideo_stream_init(
326 	struct uvideo_stream *,
327 	struct uvideo_softc *,
328 	const usb_interface_descriptor_t *,
329 	uint8_t);
330 static usbd_status		uvideo_stream_init_desc(
331 	struct uvideo_stream *,
332 	const usb_interface_descriptor_t *,
333 	usbd_desc_iter_t *);
334 static usbd_status		uvideo_stream_init_frame_based_format(
335 	struct uvideo_stream *,
336 	const uvideo_descriptor_t *,
337 	usbd_desc_iter_t *);
338 static void			uvideo_stream_free(struct uvideo_stream *);
339 
340 static int		uvideo_stream_start_xfer(struct uvideo_stream *);
341 static int		uvideo_stream_stop_xfer(struct uvideo_stream *);
342 static usbd_status	uvideo_stream_recv_process(struct uvideo_stream *,
343 						   uint8_t *, uint32_t);
344 static usbd_status	uvideo_stream_recv_isoc_start(struct uvideo_stream *);
345 static usbd_status	uvideo_stream_recv_isoc_start1(struct uvideo_isoc *);
346 static void		uvideo_stream_recv_isoc_complete(struct usbd_xfer *,
347 							 void *,
348 							 usbd_status);
349 static void		uvideo_stream_recv_bulk_transfer(void *);
350 
351 /* format probe and commit */
352 #define uvideo_stream_probe(vs, act, data)				\
353 	(uvideo_stream_probe_and_commit((vs), (act),			\
354 					UVIDEO_VS_PROBE_CONTROL, (data)))
355 #define uvideo_stream_commit(vs, act, data)				\
356 	(uvideo_stream_probe_and_commit((vs), (act),			\
357 					UVIDEO_VS_COMMIT_CONTROL, (data)))
358 static usbd_status	uvideo_stream_probe_and_commit(struct uvideo_stream *,
359 						       uint8_t, uint8_t,
360 						       void *);
361 static void		uvideo_init_probe_data(uvideo_probe_and_commit_data_t *);
362 
363 
364 static const usb_descriptor_t * usb_desc_iter_peek_next(usbd_desc_iter_t *);
365 static const usb_interface_descriptor_t * usb_desc_iter_next_interface(
366 	usbd_desc_iter_t *);
367 static const usb_descriptor_t * usb_desc_iter_next_non_interface(
368 	usbd_desc_iter_t *);
369 
370 static int	usb_guid_cmp(const usb_guid_t *, const guid_t *);
371 
372 
373 CFATTACH_DECL2_NEW(uvideo, sizeof(struct uvideo_softc),
374     uvideo_match, uvideo_attach, uvideo_detach, uvideo_activate, NULL,
375     uvideo_childdet);
376 
377 extern struct cfdriver uvideo_cd;
378 
379 
380 static const struct video_hw_if uvideo_hw_if = {
381 	.open = uvideo_open,
382 	.close = uvideo_close,
383 	.get_devname = uvideo_get_devname,
384 	.get_businfo = uvideo_get_businfo,
385 	.enum_format = uvideo_enum_format,
386 	.get_format = uvideo_get_format,
387 	.set_format = uvideo_set_format,
388 	.try_format = uvideo_try_format,
389 	.start_transfer = uvideo_start_transfer,
390 	.stop_transfer = uvideo_stop_transfer,
391 	.control_iter_init = NULL,
392 	.control_iter_next = NULL,
393 	.get_control_desc_group = NULL,
394 	.get_control_group = uvideo_get_control_group,
395 	.set_control_group = uvideo_set_control_group,
396 };
397 
398 #ifdef UVIDEO_DEBUG
399 /* Some functions to print out descriptors.  Mostly useless other than
400  * debugging/exploration purposes. */
401 static void usb_guid_print(const usb_guid_t *);
402 static void print_descriptor(const usb_descriptor_t *);
403 static void print_interface_descriptor(const usb_interface_descriptor_t *);
404 static void print_endpoint_descriptor(const usb_endpoint_descriptor_t *);
405 
406 static void print_vc_descriptor(const usb_descriptor_t *);
407 static void print_vs_descriptor(const usb_descriptor_t *);
408 
409 static void print_vc_header_descriptor(
410 	const uvideo_vc_header_descriptor_t *);
411 static void print_input_terminal_descriptor(
412 	const uvideo_input_terminal_descriptor_t *);
413 static void print_output_terminal_descriptor(
414 	const uvideo_output_terminal_descriptor_t *);
415 static void print_camera_terminal_descriptor(
416 	const uvideo_camera_terminal_descriptor_t *);
417 static void print_selector_unit_descriptor(
418 	const uvideo_selector_unit_descriptor_t *);
419 static void print_processing_unit_descriptor(
420 	const uvideo_processing_unit_descriptor_t *);
421 static void print_extension_unit_descriptor(
422 	const uvideo_extension_unit_descriptor_t *);
423 static void print_interrupt_endpoint_descriptor(
424 	const uvideo_vc_interrupt_endpoint_descriptor_t *);
425 
426 static void print_vs_input_header_descriptor(
427 	const uvideo_vs_input_header_descriptor_t *);
428 static void print_vs_output_header_descriptor(
429 	const uvideo_vs_output_header_descriptor_t *);
430 
431 static void print_vs_format_uncompressed_descriptor(
432 	const uvideo_vs_format_uncompressed_descriptor_t *);
433 static void print_vs_frame_uncompressed_descriptor(
434 	const uvideo_vs_frame_uncompressed_descriptor_t *);
435 static void print_vs_format_mjpeg_descriptor(
436 	const uvideo_vs_format_mjpeg_descriptor_t *);
437 static void print_vs_frame_mjpeg_descriptor(
438 	const uvideo_vs_frame_mjpeg_descriptor_t *);
439 static void print_vs_format_dv_descriptor(
440 	const uvideo_vs_format_dv_descriptor_t *);
441 #endif /* !UVIDEO_DEBUG */
442 
443 #define GET(type, descp, field) (((const type *)(descp))->field)
444 #define GETP(type, descp, field) (&(((const type *)(descp))->field))
445 
446 /* Given a format descriptor and frame descriptor, copy values common
447  * to all formats into a struct uvideo_format. */
448 #define UVIDEO_FORMAT_INIT_FRAME_BASED(format_type, format_desc,	\
449 				       frame_type, frame_desc,		\
450 				       format)				\
451 	do {								\
452 		UVIDEO_FORMAT_SET_FORMAT_INDEX(				\
453 			format,						\
454 			GET(format_type, format_desc, bFormatIndex));	\
455 		UVIDEO_FORMAT_SET_FRAME_INDEX(				\
456 			format,						\
457 			GET(frame_type, frame_desc, bFrameIndex));	\
458 		format->format.width =					\
459 		    UGETW(GET(frame_type, frame_desc, wWidth));		\
460 		format->format.height =					\
461 		    UGETW(GET(frame_type, frame_desc, wHeight));	\
462 		format->format.aspect_x =				\
463 		    GET(format_type, format_desc, bAspectRatioX);	\
464 		format->format.aspect_y =				\
465 		    GET(format_type, format_desc, bAspectRatioY);	\
466 	} while (0)
467 
468 
469 int
470 uvideo_match(device_t parent, cfdata_t match, void *aux)
471 {
472 	struct usbif_attach_arg *uiaa = aux;
473 
474         /* TODO: May need to change in the future to work with
475          * Interface Association Descriptor. */
476 
477 	/* Trigger on the Video Control Interface which must be present */
478 	if (uiaa->uiaa_class == UICLASS_VIDEO &&
479 	    uiaa->uiaa_subclass == UISUBCLASS_VIDEOCONTROL)
480 		return UMATCH_IFACECLASS_IFACESUBCLASS;
481 
482 	return UMATCH_NONE;
483 }
484 
485 void
486 uvideo_attach(device_t parent, device_t self, void *aux)
487 {
488 	struct uvideo_softc *sc = device_private(self);
489 	struct usbif_attach_arg *uiaa = aux;
490 	usbd_desc_iter_t iter;
491 	const usb_interface_descriptor_t *ifdesc;
492 	struct uvideo_stream *vs;
493 	usbd_status err;
494 	uint8_t ifaceidx;
495 
496 	sc->sc_dev = self;
497 
498 	sc->sc_devname = usbd_devinfo_alloc(uiaa->uiaa_device, 0);
499 
500 	aprint_naive("\n");
501 	aprint_normal(": %s\n", sc->sc_devname);
502 
503 	sc->sc_udev = uiaa->uiaa_device;
504 	sc->sc_iface = uiaa->uiaa_iface;
505 	sc->sc_ifaceno = uiaa->uiaa_ifaceno;
506 	sc->sc_dying = 0;
507 	sc->sc_state = UVIDEO_STATE_CLOSED;
508 	SLIST_INIT(&sc->sc_stream_list);
509 	snprintf(sc->sc_businfo, sizeof(sc->sc_businfo), "usb:%08x",
510 	    sc->sc_udev->ud_cookie.cookie);
511 
512 #ifdef UVIDEO_DEBUG
513 	/* Debugging dump of descriptors. TODO: move this to userspace
514 	 * via a custom IOCTL or something. */
515 	const usb_descriptor_t *desc;
516 	usb_desc_iter_init(sc->sc_udev, &iter);
517 	while ((desc = usb_desc_iter_next(&iter)) != NULL) {
518 		/* print out all descriptors */
519 		printf("uvideo_attach: ");
520 		print_descriptor(desc);
521 	}
522 #endif /* !UVIDEO_DEBUG */
523 
524 	/* iterate through interface descriptors and initialize softc */
525 	usb_desc_iter_init(sc->sc_udev, &iter);
526 	for (ifaceidx = 0;
527 	     (ifdesc = usb_desc_iter_next_interface(&iter)) != NULL;
528 	     ++ifaceidx)
529 	{
530 		if (ifdesc->bInterfaceClass != UICLASS_VIDEO) {
531 			DPRINTFN(50, ("uvideo_attach: "
532 				      "ignoring non-uvc interface: "
533 				      "len=%d type=0x%02x "
534 				      "class=0x%02x subclass=0x%02x\n",
535 				      ifdesc->bLength,
536 				      ifdesc->bDescriptorType,
537 				      ifdesc->bInterfaceClass,
538 				      ifdesc->bInterfaceSubClass));
539 			continue;
540 		}
541 
542 		switch (ifdesc->bInterfaceSubClass) {
543 		case UISUBCLASS_VIDEOCONTROL:
544 			err = uvideo_init_control(sc, ifdesc, &iter);
545 			if (err != USBD_NORMAL_COMPLETION) {
546 				DPRINTF(("uvideo_attach: error with interface "
547 					 "%d, VideoControl, "
548 					 "descriptor len=%d type=0x%02x: "
549 					 "%s (%d)\n",
550 					 ifdesc->bInterfaceNumber,
551 					 ifdesc->bLength,
552 					 ifdesc->bDescriptorType,
553 					 usbd_errstr(err), err));
554 			}
555 			break;
556 		case UISUBCLASS_VIDEOSTREAMING:
557 			vs = uvideo_find_stream(sc, ifdesc->bInterfaceNumber);
558 			if (vs == NULL) {
559 				vs = uvideo_stream_alloc();
560 				if (vs == NULL) {
561 					DPRINTF(("uvideo_attach: "
562 						 "failed to alloc stream\n"));
563 					err = USBD_NOMEM;
564 					goto bad;
565 				}
566 				err = uvideo_stream_init(vs, sc, ifdesc,
567 							 ifaceidx);
568 				if (err != USBD_NORMAL_COMPLETION) {
569 					DPRINTF(("uvideo_attach: "
570 						 "error initializing stream: "
571 						 "%s (%d)\n",
572 						 usbd_errstr(err), err));
573 					goto bad;
574 				}
575 			}
576 			err = uvideo_stream_init_desc(vs, ifdesc, &iter);
577 			if (err != USBD_NORMAL_COMPLETION) {
578 				DPRINTF(("uvideo_attach: "
579 					 "error initializing stream descriptor: "
580 					 "%s (%d)\n",
581 					 usbd_errstr(err), err));
582 				goto bad;
583 			}
584 			/* TODO: for now, set (each) stream to stream_in. */
585 			sc->sc_stream_in = vs;
586 			break;
587 		case UISUBCLASS_VIDEOCOLLECTION:
588 			err = uvideo_init_collection(sc, ifdesc, &iter);
589 			if (err != USBD_NORMAL_COMPLETION) {
590 				DPRINTF(("uvideo_attach: error with interface "
591 				       "%d, VideoCollection, "
592 				       "descriptor len=%d type=0x%02x: "
593 				       "%s (%d)\n",
594 				       ifdesc->bInterfaceNumber,
595 				       ifdesc->bLength,
596 				       ifdesc->bDescriptorType,
597 				       usbd_errstr(err), err));
598 				goto bad;
599 			}
600 			break;
601 		default:
602 			DPRINTF(("uvideo_attach: unknown UICLASS_VIDEO "
603 				 "subclass=0x%02x\n",
604 				 ifdesc->bInterfaceSubClass));
605 			break;
606 		}
607 
608 	}
609 
610 
611 	usbd_add_drv_event(USB_EVENT_DRIVER_ATTACH, sc->sc_udev, sc->sc_dev);
612 
613 	if (!pmf_device_register(self, NULL, NULL))
614 		aprint_error_dev(self, "couldn't establish power handler\n");
615 
616 	sc->sc_videodev = video_attach_mi(&uvideo_hw_if, sc->sc_dev);
617 	DPRINTF(("uvideo_attach: attached video driver at %p\n",
618 		 sc->sc_videodev));
619 
620 	return;
621 
622 bad:
623 	if (err != USBD_NORMAL_COMPLETION) {
624 		DPRINTF(("uvideo_attach: error: %s (%d)\n",
625 			 usbd_errstr(err), err));
626 	}
627 	return;
628 }
629 
630 
631 int
632 uvideo_activate(device_t self, enum devact act)
633 {
634 	struct uvideo_softc *sc = device_private(self);
635 
636 	switch (act) {
637 	case DVACT_DEACTIVATE:
638 		DPRINTF(("uvideo_activate: deactivating\n"));
639 		sc->sc_dying = 1;
640 		return 0;
641 	default:
642 		return EOPNOTSUPP;
643 	}
644 }
645 
646 
647 /* Detach child (video interface) */
648 void
649 uvideo_childdet(device_t self, device_t child)
650 {
651 	struct uvideo_softc *sc = device_private(self);
652 
653 	KASSERT(sc->sc_videodev == child);
654 	sc->sc_videodev = NULL;
655 }
656 
657 
658 int
659 uvideo_detach(device_t self, int flags)
660 {
661 	struct uvideo_softc *sc;
662 	struct uvideo_stream *vs;
663 	int rv;
664 
665 	sc = device_private(self);
666 	rv = 0;
667 
668 	sc->sc_dying = 1;
669 
670 	pmf_device_deregister(self);
671 
672 	/* TODO: close the device if it is currently opened?  Or will
673 	 * close be called automatically? */
674 
675 	while (!SLIST_EMPTY(&sc->sc_stream_list)) {
676 		vs = SLIST_FIRST(&sc->sc_stream_list);
677 		SLIST_REMOVE_HEAD(&sc->sc_stream_list, entries);
678 		uvideo_stream_stop_xfer(vs);
679 		uvideo_stream_free(vs);
680 	}
681 
682 #if 0
683 	/* Wait for outstanding request to complete.  TODO: what is
684 	 * appropriate here? */
685 	usbd_delay_ms(sc->sc_udev, 1000);
686 #endif
687 
688 	DPRINTFN(15, ("uvideo: detaching from %s\n",
689 		device_xname(sc->sc_dev)));
690 
691 	if (sc->sc_videodev != NULL)
692 		rv = config_detach(sc->sc_videodev, flags);
693 
694 	usbd_add_drv_event(USB_EVENT_DRIVER_DETACH, sc->sc_udev, sc->sc_dev);
695 
696 	usbd_devinfo_free(sc->sc_devname);
697 
698 	return rv;
699 }
700 
701 /* Search the stream list for a stream matching the interface number.
702  * This is an O(n) search, but most devices should have only one or at
703  * most two streams. */
704 static struct uvideo_stream *
705 uvideo_find_stream(struct uvideo_softc *sc, uint8_t ifaceno)
706 {
707 	struct uvideo_stream *vs;
708 
709 	SLIST_FOREACH(vs, &sc->sc_stream_list, entries) {
710 		if (vs->vs_ifaceno == ifaceno)
711 			return vs;
712 	}
713 
714 	return NULL;
715 }
716 
717 /* Search the format list for the given format and frame index.  This
718  * might be improved through indexing, but the format and frame count
719  * is unknown ahead of time (only after iterating through the
720  * usb device descriptors). */
721 #if 0
722 static struct uvideo_format *
723 uvideo_stream_find_format(struct uvideo_stream *vs,
724 			  uint8_t format_index, uint8_t frame_index)
725 {
726 	struct uvideo_format *format;
727 
728 	SIMPLEQ_FOREACH(format, &vs->vs_formats, entries) {
729 		if (UVIDEO_FORMAT_GET_FORMAT_INDEX(format) == format_index &&
730 		    UVIDEO_FORMAT_GET_FRAME_INDEX(format) == frame_index)
731 			return format;
732 	}
733 	return NULL;
734 }
735 #endif
736 
737 static struct uvideo_format *
738 uvideo_stream_guess_format(struct uvideo_stream *vs,
739 			   enum video_pixel_format pixel_format,
740 			   uint32_t width, uint32_t height)
741 {
742 	struct uvideo_format *format, *gformat = NULL;
743 
744 	SIMPLEQ_FOREACH(format, &vs->vs_formats, entries) {
745 		if (format->format.pixel_format != pixel_format)
746 			continue;
747 		if (format->format.width <= width &&
748 		    format->format.height <= height) {
749 			if (gformat == NULL ||
750 			    (gformat->format.width < format->format.width &&
751 			     gformat->format.height < format->format.height))
752 				gformat = format;
753 		}
754 	}
755 
756 	return gformat;
757 }
758 
759 static struct uvideo_stream *
760 uvideo_stream_alloc(void)
761 {
762 	return kmem_alloc(sizeof(struct uvideo_stream), KM_NOSLEEP);
763 }
764 
765 
766 static usbd_status
767 uvideo_init_control(struct uvideo_softc *sc,
768 		    const usb_interface_descriptor_t *ifdesc,
769 		    usbd_desc_iter_t *iter)
770 {
771 	const usb_descriptor_t *desc;
772 	const uvideo_descriptor_t *uvdesc;
773 	usbd_desc_iter_t orig;
774 	uint8_t i, j, nunits;
775 
776 	/* save original iterator state */
777 	memcpy(&orig, iter, sizeof(orig));
778 
779 	/* count number of units and terminals */
780 	nunits = 0;
781 	while ((desc = usb_desc_iter_next_non_interface(iter)) != NULL) {
782 		uvdesc = (const uvideo_descriptor_t *)desc;
783 
784 		if (uvdesc->bDescriptorType != UDESC_CS_INTERFACE)
785 			continue;
786 		if (uvdesc->bDescriptorSubtype < UDESC_INPUT_TERMINAL ||
787 		    uvdesc->bDescriptorSubtype > UDESC_EXTENSION_UNIT)
788 			continue;
789 		++nunits;
790 	}
791 
792 	if (nunits == 0) {
793 		DPRINTF(("uvideo_init_control: no units\n"));
794 		return USBD_NORMAL_COMPLETION;
795 	}
796 
797 	i = 0;
798 
799 	/* allocate space for units */
800 	sc->sc_nunits = nunits;
801 	sc->sc_unit = kmem_alloc(sizeof(*sc->sc_unit) * nunits, KM_SLEEP);
802 
803 	/* restore original iterator state */
804 	memcpy(iter, &orig, sizeof(orig));
805 
806 	/* iterate again, initializing the units */
807 	while ((desc = usb_desc_iter_next_non_interface(iter)) != NULL) {
808 		uvdesc = (const uvideo_descriptor_t *)desc;
809 
810 		if (uvdesc->bDescriptorType != UDESC_CS_INTERFACE)
811 			continue;
812 		if (uvdesc->bDescriptorSubtype < UDESC_INPUT_TERMINAL ||
813 		    uvdesc->bDescriptorSubtype > UDESC_EXTENSION_UNIT)
814 			continue;
815 
816 		sc->sc_unit[i] = uvideo_unit_alloc(uvdesc);
817 		/* TODO: free other units before returning? */
818 		if (sc->sc_unit[i] == NULL)
819 			goto enomem;
820 		++i;
821 	}
822 
823 	return USBD_NORMAL_COMPLETION;
824 
825 enomem:
826 	if (sc->sc_unit != NULL) {
827 		for (j = 0; j < i; ++j) {
828 			uvideo_unit_free(sc->sc_unit[j]);
829 			sc->sc_unit[j] = NULL;
830 		}
831 		kmem_free(sc->sc_unit, sizeof(*sc->sc_unit) * nunits);
832 		sc->sc_unit = NULL;
833 	}
834 	sc->sc_nunits = 0;
835 
836 	return USBD_NOMEM;
837 }
838 
839 static usbd_status
840 uvideo_init_collection(struct uvideo_softc *sc,
841 		       const usb_interface_descriptor_t *ifdesc,
842 		       usbd_desc_iter_t *iter)
843 {
844 	DPRINTF(("uvideo: ignoring Video Collection\n"));
845 	return USBD_NORMAL_COMPLETION;
846 }
847 
848 /* Allocates space for and initializes a uvideo unit based on the
849  * given descriptor.  Returns NULL with bad descriptor or ENOMEM. */
850 static struct uvideo_unit *
851 uvideo_unit_alloc(const uvideo_descriptor_t *desc)
852 {
853 	struct uvideo_unit *vu;
854 	usbd_status err;
855 
856 	if (desc->bDescriptorType != UDESC_CS_INTERFACE)
857 		return NULL;
858 
859 	vu = kmem_alloc(sizeof(*vu), KM_SLEEP);
860 	err = uvideo_unit_init(vu, desc);
861 	if (err != USBD_NORMAL_COMPLETION) {
862 		DPRINTF(("uvideo_unit_alloc: error initializing unit: "
863 			 "%s (%d)\n", usbd_errstr(err), err));
864 		kmem_free(vu, sizeof(*vu));
865 		return NULL;
866 	}
867 
868 	return vu;
869 }
870 
871 static usbd_status
872 uvideo_unit_init(struct uvideo_unit *vu, const uvideo_descriptor_t *desc)
873 {
874 	struct uvideo_camera_terminal *ct;
875 	struct uvideo_processing_unit *pu;
876 
877 	const uvideo_input_terminal_descriptor_t *input;
878 	const uvideo_camera_terminal_descriptor_t *camera;
879 	const uvideo_selector_unit_descriptor_t *selector;
880 	const uvideo_processing_unit_descriptor_t *processing;
881 	const uvideo_extension_unit_descriptor_t *extension;
882 
883 	memset(vu, 0, sizeof(*vu));
884 
885 	switch (desc->bDescriptorSubtype) {
886 	case UDESC_INPUT_TERMINAL:
887 		input = (const uvideo_input_terminal_descriptor_t *)desc;
888 		switch (UGETW(input->wTerminalType)) {
889 		case UVIDEO_ITT_CAMERA:
890 			camera =
891 			    (const uvideo_camera_terminal_descriptor_t *)desc;
892 			ct = &vu->u.vu_camera;
893 
894 			ct->ct_objective_focal_min =
895 			    UGETW(camera->wObjectiveFocalLengthMin);
896 			ct->ct_objective_focal_max =
897 			    UGETW(camera->wObjectiveFocalLengthMax);
898 			ct->ct_ocular_focal_length =
899 			    UGETW(camera->wOcularFocalLength);
900 
901 			uvideo_unit_alloc_controls(vu, camera->bControlSize,
902 						   camera->bmControls);
903 			break;
904 		default:
905 			DPRINTF(("uvideo_unit_init: "
906 				 "unknown input terminal type 0x%04x\n",
907 				 UGETW(input->wTerminalType)));
908 			return USBD_INVAL;
909 		}
910 		break;
911 	case UDESC_OUTPUT_TERMINAL:
912 		break;
913 	case UDESC_SELECTOR_UNIT:
914 		selector = (const uvideo_selector_unit_descriptor_t *)desc;
915 
916 		uvideo_unit_alloc_sources(vu, selector->bNrInPins,
917 					  selector->baSourceID);
918 		break;
919 	case UDESC_PROCESSING_UNIT:
920 		processing = (const uvideo_processing_unit_descriptor_t *)desc;
921 		pu = &vu->u.vu_processing;
922 
923 		pu->pu_video_standards = PU_GET_VIDEO_STANDARDS(processing);
924 		pu->pu_max_multiplier = UGETW(processing->wMaxMultiplier);
925 
926 		uvideo_unit_alloc_sources(vu, 1, &processing->bSourceID);
927 		uvideo_unit_alloc_controls(vu, processing->bControlSize,
928 					   processing->bmControls);
929 		break;
930 	case UDESC_EXTENSION_UNIT:
931 		extension = (const uvideo_extension_unit_descriptor_t *)desc;
932 		/* TODO: copy guid */
933 
934 		uvideo_unit_alloc_sources(vu, extension->bNrInPins,
935 					  extension->baSourceID);
936 		uvideo_unit_alloc_controls(vu, XU_GET_CONTROL_SIZE(extension),
937 					   XU_GET_CONTROLS(extension));
938 		break;
939 	default:
940 		DPRINTF(("uvideo_unit_alloc: unknown descriptor "
941 			 "type=0x%02x subtype=0x%02x\n",
942 			 desc->bDescriptorType, desc->bDescriptorSubtype));
943 		return USBD_INVAL;
944 	}
945 
946 	return USBD_NORMAL_COMPLETION;
947 }
948 
949 static void
950 uvideo_unit_free(struct uvideo_unit *vu)
951 {
952 	uvideo_unit_free_sources(vu);
953 	uvideo_unit_free_controls(vu);
954 	kmem_free(vu, sizeof(*vu));
955 }
956 
957 static usbd_status
958 uvideo_unit_alloc_sources(struct uvideo_unit *vu,
959 			  uint8_t nsrcs, const uint8_t *src_ids)
960 {
961 	vu->vu_nsrcs = nsrcs;
962 
963 	if (nsrcs == 0) {
964 		/* do nothing */
965 	} else if (nsrcs == 1) {
966 		vu->s.vu_src_id = src_ids[0];
967 	} else {
968 		vu->s.vu_src_id_ary =
969 		    kmem_alloc(sizeof(*vu->s.vu_src_id_ary) * nsrcs, KM_SLEEP);
970 		memcpy(vu->s.vu_src_id_ary, src_ids, nsrcs);
971 	}
972 
973 	return USBD_NORMAL_COMPLETION;
974 }
975 
976 static void
977 uvideo_unit_free_sources(struct uvideo_unit *vu)
978 {
979 	if (vu->vu_nsrcs == 1)
980 		return;
981 
982 	kmem_free(vu->s.vu_src_id_ary,
983 		  sizeof(*vu->s.vu_src_id_ary) * vu->vu_nsrcs);
984 	vu->vu_nsrcs = 0;
985 	vu->s.vu_src_id_ary = NULL;
986 }
987 
988 static usbd_status
989 uvideo_unit_alloc_controls(struct uvideo_unit *vu, uint8_t size,
990 			   const uint8_t *controls)
991 {
992 	vu->vu_controls = kmem_alloc(sizeof(*vu->vu_controls) * size, KM_SLEEP);
993 	vu->vu_control_size = size;
994 	memcpy(vu->vu_controls, controls, size);
995 
996 	return USBD_NORMAL_COMPLETION;
997 }
998 
999 static void
1000 uvideo_unit_free_controls(struct uvideo_unit *vu)
1001 {
1002 	kmem_free(vu->vu_controls,
1003 		  sizeof(*vu->vu_controls) * vu->vu_control_size);
1004 	vu->vu_controls = NULL;
1005 	vu->vu_control_size = 0;
1006 }
1007 
1008 
1009 /* Initialize a stream from a Video Streaming interface
1010  * descriptor. Adds the stream to the stream_list in uvideo_softc.
1011  * This should be called once for new streams, and
1012  * uvideo_stream_init_desc() should then be called for this and each
1013  * additional interface with the same interface number. */
1014 static usbd_status
1015 uvideo_stream_init(struct uvideo_stream *vs,
1016 		   struct uvideo_softc *sc,
1017 		   const usb_interface_descriptor_t *ifdesc,
1018 		   uint8_t idx)
1019 {
1020 	uWord len;
1021 	usbd_status err;
1022 
1023 	SLIST_INSERT_HEAD(&sc->sc_stream_list, vs, entries);
1024 	memset(vs, 0, sizeof(*vs));
1025 	vs->vs_parent = sc;
1026 	vs->vs_ifaceno = ifdesc->bInterfaceNumber;
1027 	vs->vs_subtype = 0;
1028 	SIMPLEQ_INIT(&vs->vs_formats);
1029 	SIMPLEQ_INIT(&vs->vs_pixel_formats);
1030 	vs->vs_default_format = NULL;
1031 	vs->vs_current_format.priv = -1;
1032 	vs->vs_xfer_type = 0;
1033 
1034 	err = usbd_device2interface_handle(sc->sc_udev, idx, &vs->vs_iface);
1035 	if (err != USBD_NORMAL_COMPLETION) {
1036 		DPRINTF(("uvideo_stream_init: "
1037 			 "error getting vs interface: "
1038 			 "%s (%d)\n",
1039 			 usbd_errstr(err), err));
1040 		return err;
1041 	}
1042 
1043 	/* For Xbox Live Vision camera, linux-uvc folk say we need to
1044 	 * set an alternate interface and wait ~3 seconds prior to
1045 	 * doing the format probe/commit.  We set to alternate
1046 	 * interface 0, which is the default, zero bandwidth
1047 	 * interface.  This should not have adverse affects on other
1048 	 * cameras.  Errors are ignored. */
1049 	err = usbd_set_interface(vs->vs_iface, 0);
1050 	if (err != USBD_NORMAL_COMPLETION) {
1051 		DPRINTF(("uvideo_stream_init: error setting alt interface: "
1052 			 "%s (%d)\n",
1053 			 usbd_errstr(err), err));
1054 	}
1055 
1056 	/* Initialize probe and commit data size.  This value is
1057 	 * dependent on the version of the spec the hardware
1058 	 * implements. */
1059 	err = uvideo_stream_probe(vs, UR_GET_LEN, &len);
1060 	if (err != USBD_NORMAL_COMPLETION) {
1061 		DPRINTF(("uvideo_stream_init: "
1062 			 "error getting probe data len: "
1063 			 "%s (%d)\n",
1064 			 usbd_errstr(err), err));
1065 		vs->vs_probelen = 26; /* conservative v1.0 length */
1066 	} else if (UGETW(len) <= sizeof(uvideo_probe_and_commit_data_t)) {
1067 		DPRINTFN(15,("uvideo_stream_init: probelen=%d\n", UGETW(len)));
1068 		vs->vs_probelen = UGETW(len);
1069 	} else {
1070 		DPRINTFN(15,("uvideo_stream_init: device returned invalid probe"
1071 				" len %d, using default\n", UGETW(len)));
1072 		vs->vs_probelen = 26;
1073 	}
1074 
1075 	return USBD_NORMAL_COMPLETION;
1076 }
1077 
1078 /* Further stream initialization based on a Video Streaming interface
1079  * descriptor and following descriptors belonging to that interface.
1080  * Iterates through all descriptors belonging to this particular
1081  * interface descriptor, modifying the iterator.  This may be called
1082  * multiple times because there may be several alternate interfaces
1083  * associated with the same interface number. */
1084 static usbd_status
1085 uvideo_stream_init_desc(struct uvideo_stream *vs,
1086 			const usb_interface_descriptor_t *ifdesc,
1087 			usbd_desc_iter_t *iter)
1088 {
1089 	const usb_descriptor_t *desc;
1090 	const uvideo_descriptor_t *uvdesc;
1091 	struct uvideo_bulk_xfer *bx;
1092 	struct uvideo_isoc_xfer *ix;
1093 	struct uvideo_alternate *alt;
1094 	uint8_t xfer_type, xfer_dir;
1095 	uint8_t bmAttributes, bEndpointAddress;
1096 	int i;
1097 
1098 	/* Iterate until the next interface descriptor.  All
1099 	 * descriptors until then belong to this streaming
1100 	 * interface. */
1101 	while ((desc = usb_desc_iter_next_non_interface(iter)) != NULL) {
1102 		uvdesc = (const uvideo_descriptor_t *)desc;
1103 
1104 		switch (uvdesc->bDescriptorType) {
1105 		case UDESC_ENDPOINT:
1106 			bmAttributes = GET(usb_endpoint_descriptor_t,
1107 					   desc, bmAttributes);
1108 			bEndpointAddress = GET(usb_endpoint_descriptor_t,
1109 					       desc, bEndpointAddress);
1110 			xfer_type = UE_GET_XFERTYPE(bmAttributes);
1111 			xfer_dir = UE_GET_DIR(bEndpointAddress);
1112 			if (xfer_type == UE_BULK && xfer_dir == UE_DIR_IN) {
1113 				bx = &vs->vs_xfer.bulk;
1114 				if (vs->vs_xfer_type == 0) {
1115 					DPRINTFN(15, ("uvideo_attach: "
1116 						      "BULK stream *\n"));
1117 					vs->vs_xfer_type = UE_BULK;
1118 					bx->bx_endpt = bEndpointAddress;
1119 					DPRINTF(("uvideo_attach: BULK "
1120 						 "endpoint %x\n",
1121 						 bx->bx_endpt));
1122 					bx->bx_running = false;
1123 					cv_init(&bx->bx_cv,
1124 					    device_xname(vs->vs_parent->sc_dev)
1125 					    );
1126 					mutex_init(&bx->bx_lock,
1127 					  MUTEX_DEFAULT, IPL_NONE);
1128 				}
1129 			} else if (xfer_type == UE_ISOCHRONOUS) {
1130 				ix = &vs->vs_xfer.isoc;
1131 				for (i = 0; i < UVIDEO_NXFERS; i++) {
1132 					ix->ix_i[i].i_ix = ix;
1133 					ix->ix_i[i].i_vs = vs;
1134 				}
1135 				if (vs->vs_xfer_type == 0) {
1136 					DPRINTFN(15, ("uvideo_attach: "
1137 						      "ISOC stream *\n"));
1138 					SLIST_INIT(&ix->ix_altlist);
1139 					vs->vs_xfer_type = UE_ISOCHRONOUS;
1140 					ix->ix_endpt =
1141 					    GET(usb_endpoint_descriptor_t,
1142 						desc, bEndpointAddress);
1143 				}
1144 
1145 				alt = kmem_alloc(sizeof(*alt), KM_NOSLEEP);
1146 				if (alt == NULL)
1147 					return USBD_NOMEM;
1148 
1149 				alt->altno = ifdesc->bAlternateSetting;
1150 				alt->interval =
1151 				    GET(usb_endpoint_descriptor_t,
1152 					desc, bInterval);
1153 
1154 				alt->max_packet_size =
1155 				UE_GET_SIZE(UGETW(GET(usb_endpoint_descriptor_t,
1156 					desc, wMaxPacketSize)));
1157 				alt->max_packet_size *=
1158 					(UE_GET_TRANS(UGETW(GET(
1159 						usb_endpoint_descriptor_t, desc,
1160 						wMaxPacketSize)))) + 1;
1161 
1162 				SLIST_INSERT_HEAD(&ix->ix_altlist,
1163 						  alt, entries);
1164 			}
1165 			break;
1166 		case UDESC_CS_INTERFACE:
1167 			if (ifdesc->bAlternateSetting != 0) {
1168 				DPRINTF(("uvideo_stream_init_alternate: "
1169 					 "unexpected class-specific descriptor "
1170 					 "len=%d type=0x%02x subtype=0x%02x\n",
1171 					 uvdesc->bLength,
1172 					 uvdesc->bDescriptorType,
1173 					 uvdesc->bDescriptorSubtype));
1174 				break;
1175 			}
1176 
1177 			switch (uvdesc->bDescriptorSubtype) {
1178 			case UDESC_VS_INPUT_HEADER:
1179 				vs->vs_subtype = UDESC_VS_INPUT_HEADER;
1180 				break;
1181 			case UDESC_VS_OUTPUT_HEADER:
1182 				/* TODO: handle output stream */
1183 				DPRINTF(("uvideo: VS output not implemented\n"));
1184 				vs->vs_subtype = UDESC_VS_OUTPUT_HEADER;
1185 				return USBD_INVAL;
1186 			case UDESC_VS_FORMAT_UNCOMPRESSED:
1187 			case UDESC_VS_FORMAT_FRAME_BASED:
1188 			case UDESC_VS_FORMAT_MJPEG:
1189 				uvideo_stream_init_frame_based_format(vs,
1190 								      uvdesc,
1191 								      iter);
1192 				break;
1193 			case UDESC_VS_FORMAT_MPEG2TS:
1194 			case UDESC_VS_FORMAT_DV:
1195 			case UDESC_VS_FORMAT_STREAM_BASED:
1196 			default:
1197 				DPRINTF(("uvideo: unimplemented VS CS "
1198 					 "descriptor len=%d type=0x%02x "
1199 					 "subtype=0x%02x\n",
1200 					 uvdesc->bLength,
1201 					 uvdesc->bDescriptorType,
1202 					 uvdesc->bDescriptorSubtype));
1203 				break;
1204 			}
1205 			break;
1206 		default:
1207 			DPRINTF(("uvideo_stream_init_desc: "
1208 				 "unknown descriptor "
1209 				 "len=%d type=0x%02x\n",
1210 				 uvdesc->bLength,
1211 				 uvdesc->bDescriptorType));
1212 			break;
1213 		}
1214 	}
1215 
1216 	return USBD_NORMAL_COMPLETION;
1217 }
1218 
1219 /* Finialize and free memory associated with this stream. */
1220 static void
1221 uvideo_stream_free(struct uvideo_stream *vs)
1222 {
1223 	struct uvideo_alternate *alt;
1224 	struct uvideo_pixel_format *pixel_format;
1225 	struct uvideo_format *format;
1226 
1227 	/* free linked list of alternate interfaces */
1228 	if (vs->vs_xfer_type == UE_ISOCHRONOUS) {
1229 		while (!SLIST_EMPTY(&vs->vs_xfer.isoc.ix_altlist)) {
1230 			alt = SLIST_FIRST(&vs->vs_xfer.isoc.ix_altlist);
1231 			SLIST_REMOVE_HEAD(&vs->vs_xfer.isoc.ix_altlist,
1232 					  entries);
1233 			kmem_free(alt, sizeof(*alt));
1234 		}
1235 	}
1236 
1237 	/* free linked-list of formats and pixel formats */
1238 	while ((format = SIMPLEQ_FIRST(&vs->vs_formats)) != NULL) {
1239 		SIMPLEQ_REMOVE_HEAD(&vs->vs_formats, entries);
1240 		kmem_free(format, sizeof(struct uvideo_format));
1241 	}
1242 	while ((pixel_format = SIMPLEQ_FIRST(&vs->vs_pixel_formats)) != NULL) {
1243 		SIMPLEQ_REMOVE_HEAD(&vs->vs_pixel_formats, entries);
1244 		kmem_free(pixel_format, sizeof(struct uvideo_pixel_format));
1245 	}
1246 
1247 	kmem_free(vs, sizeof(*vs));
1248 }
1249 
1250 
1251 static usbd_status
1252 uvideo_stream_init_frame_based_format(struct uvideo_stream *vs,
1253 				      const uvideo_descriptor_t *format_desc,
1254 				      usbd_desc_iter_t *iter)
1255 {
1256 	struct uvideo_pixel_format *pformat, *pfiter;
1257 	enum video_pixel_format pixel_format;
1258 	struct uvideo_format *format;
1259 	const uvideo_descriptor_t *uvdesc;
1260 	uint8_t subtype, default_index, index;
1261 	uint32_t frame_interval;
1262 	const usb_guid_t *guid;
1263 
1264 	pixel_format = VIDEO_FORMAT_UNDEFINED;
1265 
1266 	switch (format_desc->bDescriptorSubtype) {
1267 	case UDESC_VS_FORMAT_UNCOMPRESSED:
1268 		subtype = UDESC_VS_FRAME_UNCOMPRESSED;
1269 		default_index = GET(uvideo_vs_format_uncompressed_descriptor_t,
1270 				    format_desc,
1271 				    bDefaultFrameIndex);
1272 		guid = GETP(uvideo_vs_format_uncompressed_descriptor_t,
1273 			    format_desc,
1274 			    guidFormat);
1275 		if (usb_guid_cmp(guid, &uvideo_guid_format_yuy2) == 0)
1276 			pixel_format = VIDEO_FORMAT_YUY2;
1277 		else if (usb_guid_cmp(guid, &uvideo_guid_format_nv12) == 0)
1278 			pixel_format = VIDEO_FORMAT_NV12;
1279 		else if (usb_guid_cmp(guid, &uvideo_guid_format_uyvy) == 0)
1280 			pixel_format = VIDEO_FORMAT_UYVY;
1281 		break;
1282 	case UDESC_VS_FORMAT_FRAME_BASED:
1283 		subtype = UDESC_VS_FRAME_FRAME_BASED;
1284 		default_index = GET(uvideo_format_frame_based_descriptor_t,
1285 				    format_desc,
1286 				    bDefaultFrameIndex);
1287 		break;
1288 	case UDESC_VS_FORMAT_MJPEG:
1289 		subtype = UDESC_VS_FRAME_MJPEG;
1290 		default_index = GET(uvideo_vs_format_mjpeg_descriptor_t,
1291 				    format_desc,
1292 				    bDefaultFrameIndex);
1293 		pixel_format = VIDEO_FORMAT_MJPEG;
1294 		break;
1295 	default:
1296 		DPRINTF(("uvideo: unknown frame based format %d\n",
1297 			 format_desc->bDescriptorSubtype));
1298 		return USBD_INVAL;
1299 	}
1300 
1301 	pformat = NULL;
1302 	SIMPLEQ_FOREACH(pfiter, &vs->vs_pixel_formats, entries) {
1303 		if (pfiter->pixel_format == pixel_format) {
1304 			pformat = pfiter;
1305 			break;
1306 		}
1307 	}
1308 	if (pixel_format != VIDEO_FORMAT_UNDEFINED && pformat == NULL) {
1309 		pformat = kmem_zalloc(sizeof(*pformat), KM_SLEEP);
1310 		pformat->pixel_format = pixel_format;
1311 		DPRINTF(("uvideo: Adding pixel format %d\n",
1312 		    pixel_format));
1313 		SIMPLEQ_INSERT_TAIL(&vs->vs_pixel_formats,
1314 		    pformat, entries);
1315 	}
1316 
1317 	/* Iterate through frame descriptors directly following the
1318 	 * format descriptor, and add a format to the format list for
1319 	 * each frame descriptor. */
1320 	while ((uvdesc = (const uvideo_descriptor_t *) usb_desc_iter_peek_next(iter)) &&
1321 	       (uvdesc != NULL) && (uvdesc->bDescriptorSubtype == subtype))
1322 	{
1323 		uvdesc = (const uvideo_descriptor_t *) usb_desc_iter_next(iter);
1324 
1325 		format = kmem_zalloc(sizeof(struct uvideo_format), KM_SLEEP);
1326 		format->format.pixel_format = pixel_format;
1327 
1328 		switch (format_desc->bDescriptorSubtype) {
1329 		case UDESC_VS_FORMAT_UNCOMPRESSED:
1330 #ifdef UVIDEO_DEBUG
1331 			if (pixel_format == VIDEO_FORMAT_UNDEFINED &&
1332 			    uvideodebug) {
1333 				guid = GETP(
1334 				    uvideo_vs_format_uncompressed_descriptor_t,
1335 				    format_desc,
1336 				    guidFormat);
1337 
1338 				DPRINTF(("uvideo: format undefined "));
1339 				usb_guid_print(guid);
1340 				DPRINTF(("\n"));
1341 			}
1342 #endif
1343 
1344 			UVIDEO_FORMAT_INIT_FRAME_BASED(
1345 				uvideo_vs_format_uncompressed_descriptor_t,
1346 				format_desc,
1347 				uvideo_vs_frame_uncompressed_descriptor_t,
1348 				uvdesc,
1349 				format);
1350 			format->format.sample_size =
1351 			    UGETDW(
1352 			      GET(uvideo_vs_frame_uncompressed_descriptor_t,
1353 			      uvdesc, dwMaxVideoFrameBufferSize));
1354 			format->format.stride =
1355 			    format->format.sample_size / format->format.height;
1356 			index = GET(uvideo_vs_frame_uncompressed_descriptor_t,
1357 				    uvdesc,
1358 				    bFrameIndex);
1359 			frame_interval =
1360 			    UGETDW(
1361 				GET(uvideo_vs_frame_uncompressed_descriptor_t,
1362 				uvdesc,
1363 				dwDefaultFrameInterval));
1364 			break;
1365 		case UDESC_VS_FORMAT_MJPEG:
1366 			UVIDEO_FORMAT_INIT_FRAME_BASED(
1367 				uvideo_vs_format_mjpeg_descriptor_t,
1368 				format_desc,
1369 				uvideo_vs_frame_mjpeg_descriptor_t,
1370 				uvdesc,
1371 				format);
1372 			format->format.sample_size =
1373 			    UGETDW(
1374 				GET(uvideo_vs_frame_mjpeg_descriptor_t,
1375 			        uvdesc, dwMaxVideoFrameBufferSize));
1376 			format->format.stride =
1377 			    format->format.sample_size / format->format.height;
1378 			index = GET(uvideo_vs_frame_mjpeg_descriptor_t,
1379 				    uvdesc,
1380 				    bFrameIndex);
1381 			frame_interval =
1382 			    UGETDW(
1383 				GET(uvideo_vs_frame_mjpeg_descriptor_t,
1384 				uvdesc,
1385 				dwDefaultFrameInterval));
1386 			break;
1387 		case UDESC_VS_FORMAT_FRAME_BASED:
1388 			format->format.pixel_format = VIDEO_FORMAT_UNDEFINED;
1389 			UVIDEO_FORMAT_INIT_FRAME_BASED(
1390 				uvideo_format_frame_based_descriptor_t,
1391 				format_desc,
1392 				uvideo_frame_frame_based_descriptor_t,
1393 				uvdesc,
1394 				format);
1395 			index = GET(uvideo_frame_frame_based_descriptor_t,
1396 				    uvdesc,
1397 				    bFrameIndex);
1398 			format->format.stride =
1399 			    UGETDW(
1400 				GET(uvideo_frame_frame_based_descriptor_t,
1401 			        uvdesc, dwBytesPerLine));
1402 			format->format.sample_size =
1403 			    format->format.stride * format->format.height;
1404 			frame_interval =
1405 			    UGETDW(
1406 				GET(uvideo_frame_frame_based_descriptor_t,
1407 				uvdesc, dwDefaultFrameInterval));
1408 			break;
1409 		default:
1410 			/* shouldn't ever get here */
1411 			DPRINTF(("uvideo: unknown frame based format %d\n",
1412 				 format_desc->bDescriptorSubtype));
1413 			kmem_free(format, sizeof(struct uvideo_format));
1414 			return USBD_INVAL;
1415 		}
1416 
1417 		DPRINTF(("uvideo: found format (index %d) type %d "
1418 		    "size %ux%u size %u stride %u interval %u\n",
1419 		    index, format->format.pixel_format, format->format.width,
1420 		    format->format.height, format->format.sample_size,
1421 		    format->format.stride, frame_interval));
1422 
1423 		SIMPLEQ_INSERT_TAIL(&vs->vs_formats, format, entries);
1424 
1425 		if (vs->vs_default_format == NULL && index == default_index
1426 #ifdef UVIDEO_DISABLE_MJPEG
1427 		    && subtype != UDESC_VS_FRAME_MJPEG
1428 #endif
1429 		    ) {
1430 			DPRINTF((" ^ picking this one\n"));
1431 			vs->vs_default_format = &format->format;
1432 			vs->vs_frame_interval = frame_interval;
1433 		}
1434 
1435 	}
1436 
1437 	return USBD_NORMAL_COMPLETION;
1438 }
1439 
1440 static int
1441 uvideo_stream_start_xfer(struct uvideo_stream *vs)
1442 {
1443 	struct uvideo_softc *sc = vs->vs_parent;
1444 	struct uvideo_bulk_xfer *bx;
1445 	struct uvideo_isoc_xfer *ix;
1446 	uint32_t vframe_len;	/* rough bytes per video frame */
1447 	uint32_t uframe_len;	/* bytes per usb frame (TODO: or microframe?) */
1448 	uint32_t nframes;	/* number of usb frames (TODO: or microframs?) */
1449 	int i, ret;
1450 	int error;
1451 
1452 	struct uvideo_alternate *alt, *alt_maybe;
1453 	usbd_status err;
1454 
1455 	switch (vs->vs_xfer_type) {
1456 	case UE_BULK:
1457 		ret = 0;
1458 		bx = &vs->vs_xfer.bulk;
1459 
1460 		err = usbd_open_pipe(vs->vs_iface, bx->bx_endpt, 0,
1461 		    &bx->bx_pipe);
1462 		if (err != USBD_NORMAL_COMPLETION) {
1463 			DPRINTF(("uvideo: error opening pipe: %s (%d)\n",
1464 				 usbd_errstr(err), err));
1465 			return EIO;
1466 		}
1467 		DPRINTF(("uvideo: pipe %p\n", bx->bx_pipe));
1468 
1469 		error = usbd_create_xfer(bx->bx_pipe, vs->vs_max_payload_size,
1470 		    0, 0, &bx->bx_xfer);
1471 		if (error) {
1472 			DPRINTF(("uvideo: couldn't allocate xfer\n"));
1473 			return error;
1474 		}
1475 		DPRINTF(("uvideo: xfer %p\n", bx->bx_xfer));
1476 
1477 		bx->bx_buflen = vs->vs_max_payload_size;
1478 		bx->bx_buffer = usbd_get_buffer(bx->bx_xfer);
1479 
1480 		mutex_enter(&bx->bx_lock);
1481 		if (bx->bx_running == false) {
1482 			bx->bx_running = true;
1483 			ret = kthread_create(PRI_UVIDEO, 0, NULL,
1484 			    uvideo_stream_recv_bulk_transfer, vs,
1485 			    NULL, "%s", device_xname(sc->sc_dev));
1486 			if (ret) {
1487 				DPRINTF(("uvideo: couldn't create kthread:"
1488 					 " %d\n", err));
1489 				bx->bx_running = false;
1490 				mutex_exit(&bx->bx_lock);
1491 				return err;
1492 			}
1493 		} else
1494 			aprint_error_dev(sc->sc_dev,
1495 			    "transfer already in progress\n");
1496 		mutex_exit(&bx->bx_lock);
1497 
1498 		DPRINTF(("uvideo: thread created\n"));
1499 
1500 		return 0;
1501 	case UE_ISOCHRONOUS:
1502 		ix = &vs->vs_xfer.isoc;
1503 
1504 		/* Choose an alternate interface most suitable for
1505 		 * this format.  Choose the smallest size that can
1506 		 * contain max_payload_size.
1507 		 *
1508 		 * It is assumed that the list is sorted in descending
1509 		 * order from largest to smallest packet size.
1510 		 *
1511 		 * TODO: what should the strategy be for choosing an
1512 		 * alt interface?
1513 		 */
1514 		alt = NULL;
1515 		SLIST_FOREACH(alt_maybe, &ix->ix_altlist, entries) {
1516 			/* TODO: define "packet" and "payload".  I think
1517 			 * several packets can make up one payload which would
1518 			 * call into question this method of selecting an
1519 			 * alternate interface... */
1520 
1521 			if (alt_maybe->max_packet_size > vs->vs_max_payload_size)
1522 				continue;
1523 
1524 			if (alt == NULL ||
1525 			    alt_maybe->max_packet_size >= alt->max_packet_size)
1526 				alt = alt_maybe;
1527 		}
1528 
1529 		if (alt == NULL) {
1530 			DPRINTF(("uvideo_stream_start_xfer: "
1531 				 "no suitable alternate interface found\n"));
1532 			return EINVAL;
1533 		}
1534 
1535 		DPRINTFN(15,("uvideo_stream_start_xfer: "
1536 			     "choosing alternate interface "
1537 			     "%d wMaxPacketSize=%d bInterval=%d\n",
1538 			     alt->altno, alt->max_packet_size, alt->interval));
1539 
1540 		err = usbd_set_interface(vs->vs_iface, alt->altno);
1541 		if (err != USBD_NORMAL_COMPLETION) {
1542 			DPRINTF(("uvideo_stream_start_xfer: "
1543 				 "error setting alt interface: %s (%d)\n",
1544 				 usbd_errstr(err), err));
1545 			return EIO;
1546 		}
1547 
1548 		/* TODO: "packet" not same as frame */
1549 		vframe_len = vs->vs_current_format.sample_size;
1550 		uframe_len = alt->max_packet_size;
1551 		nframes = (vframe_len + uframe_len - 1) / uframe_len;
1552 		nframes = (nframes + 7) & ~7; /*round up for ehci inefficiency*/
1553 		DPRINTF(("uvideo_stream_start_xfer: nframes=%d\n", nframes));
1554 
1555 		ix->ix_nframes = nframes;
1556 		ix->ix_uframe_len = uframe_len;
1557 		for (i = 0; i < UVIDEO_NXFERS; i++) {
1558 			struct uvideo_isoc *isoc = &ix->ix_i[i];
1559 			isoc->i_frlengths =
1560 			    kmem_alloc(sizeof(isoc->i_frlengths[0]) * nframes,
1561 				KM_SLEEP);
1562 		}
1563 
1564 		err = usbd_open_pipe(vs->vs_iface, ix->ix_endpt,
1565 				     USBD_EXCLUSIVE_USE, &ix->ix_pipe);
1566 		if (err != USBD_NORMAL_COMPLETION) {
1567 			DPRINTF(("uvideo: error opening pipe: %s (%d)\n",
1568 				 usbd_errstr(err), err));
1569 			return EIO;
1570 		}
1571 
1572 		for (i = 0; i < UVIDEO_NXFERS; i++) {
1573 			struct uvideo_isoc *isoc = &ix->ix_i[i];
1574 			error = usbd_create_xfer(ix->ix_pipe,
1575 			    nframes * uframe_len, 0, ix->ix_nframes,
1576 			    &isoc->i_xfer);
1577 			if (error) {
1578 				DPRINTF(("uvideo: "
1579 				    "couldn't allocate xfer (%d)\n", error));
1580 				return error;
1581 			}
1582 
1583 			isoc->i_buf = usbd_get_buffer(isoc->i_xfer);
1584 		}
1585 
1586 		uvideo_stream_recv_isoc_start(vs);
1587 
1588 		return 0;
1589 	default:
1590 		/* should never get here */
1591 		DPRINTF(("uvideo_stream_start_xfer: unknown xfer type 0x%x\n",
1592 			 vs->vs_xfer_type));
1593 		return EINVAL;
1594 	}
1595 }
1596 
1597 static int
1598 uvideo_stream_stop_xfer(struct uvideo_stream *vs)
1599 {
1600 	struct uvideo_bulk_xfer *bx;
1601 	struct uvideo_isoc_xfer *ix;
1602 	usbd_status err;
1603 	int i;
1604 
1605 	switch (vs->vs_xfer_type) {
1606 	case UE_BULK:
1607 		bx = &vs->vs_xfer.bulk;
1608 
1609 		DPRINTF(("uvideo_stream_stop_xfer: UE_BULK: "
1610 			 "waiting for thread to complete\n"));
1611 		mutex_enter(&bx->bx_lock);
1612 		if (bx->bx_running == true) {
1613 			bx->bx_running = false;
1614 			cv_wait_sig(&bx->bx_cv, &bx->bx_lock);
1615 		}
1616 		mutex_exit(&bx->bx_lock);
1617 
1618 		DPRINTF(("uvideo_stream_stop_xfer: UE_BULK: cleaning up\n"));
1619 
1620 		if (bx->bx_pipe) {
1621 			usbd_abort_pipe(bx->bx_pipe);
1622 		}
1623 
1624 		if (bx->bx_xfer) {
1625 			usbd_destroy_xfer(bx->bx_xfer);
1626 			bx->bx_xfer = NULL;
1627 		}
1628 
1629 		if (bx->bx_pipe) {
1630 			usbd_close_pipe(bx->bx_pipe);
1631 			bx->bx_pipe = NULL;
1632 		}
1633 
1634 		DPRINTF(("uvideo_stream_stop_xfer: UE_BULK: done\n"));
1635 
1636 		return 0;
1637 	case UE_ISOCHRONOUS:
1638 		ix = &vs->vs_xfer.isoc;
1639 		if (ix->ix_pipe != NULL) {
1640 			usbd_abort_pipe(ix->ix_pipe);
1641 		}
1642 
1643 		for (i = 0; i < UVIDEO_NXFERS; i++) {
1644 			struct uvideo_isoc *isoc = &ix->ix_i[i];
1645 			if (isoc->i_xfer != NULL) {
1646 				usbd_destroy_xfer(isoc->i_xfer);
1647 				isoc->i_xfer = NULL;
1648 			}
1649 
1650 			if (isoc->i_frlengths != NULL) {
1651 				kmem_free(isoc->i_frlengths,
1652 				  sizeof(isoc->i_frlengths[0]) *
1653 				  ix->ix_nframes);
1654 				isoc->i_frlengths = NULL;
1655 			}
1656 		}
1657 
1658 		if (ix->ix_pipe != NULL) {
1659 			usbd_close_pipe(ix->ix_pipe);
1660 			ix->ix_pipe = NULL;
1661 		}
1662 		/* Give it some time to settle */
1663 		usbd_delay_ms(vs->vs_parent->sc_udev, 1000);
1664 
1665 		/* Set to zero bandwidth alternate interface zero */
1666 		err = usbd_set_interface(vs->vs_iface, 0);
1667 		if (err != USBD_NORMAL_COMPLETION) {
1668 			DPRINTF(("uvideo_stream_stop_transfer: "
1669 				 "error setting zero bandwidth interface: "
1670 				 "%s (%d)\n",
1671 				 usbd_errstr(err), err));
1672 			return EIO;
1673 		}
1674 
1675 		return 0;
1676 	default:
1677 		/* should never get here */
1678 		DPRINTF(("uvideo_stream_stop_xfer: unknown xfer type 0x%x\n",
1679 			 vs->vs_xfer_type));
1680 		return EINVAL;
1681 	}
1682 }
1683 
1684 static usbd_status
1685 uvideo_stream_recv_isoc_start(struct uvideo_stream *vs)
1686 {
1687 	int i;
1688 
1689 	for (i = 0; i < UVIDEO_NXFERS; i++)
1690 		uvideo_stream_recv_isoc_start1(&vs->vs_xfer.isoc.ix_i[i]);
1691 
1692 	return USBD_NORMAL_COMPLETION;
1693 }
1694 
1695 /* Initiate a usb transfer. */
1696 static usbd_status
1697 uvideo_stream_recv_isoc_start1(struct uvideo_isoc *isoc)
1698 {
1699 	struct uvideo_isoc_xfer *ix;
1700 	usbd_status err;
1701 	int i;
1702 
1703 	ix = isoc->i_ix;
1704 
1705 	for (i = 0; i < ix->ix_nframes; ++i)
1706 		isoc->i_frlengths[i] = ix->ix_uframe_len;
1707 
1708 	usbd_setup_isoc_xfer(isoc->i_xfer,
1709 			     isoc,
1710 			     isoc->i_frlengths,
1711 			     ix->ix_nframes,
1712 			     USBD_SHORT_XFER_OK,
1713 			     uvideo_stream_recv_isoc_complete);
1714 
1715 	err = usbd_transfer(isoc->i_xfer);
1716 	if (err != USBD_IN_PROGRESS) {
1717 		DPRINTF(("uvideo_stream_recv_start: "
1718 			 "usbd_transfer status=%s (%d)\n",
1719 			 usbd_errstr(err), err));
1720 	}
1721 	return err;
1722 }
1723 
1724 static usbd_status
1725 uvideo_stream_recv_process(struct uvideo_stream *vs, uint8_t *buf, uint32_t len)
1726 {
1727 	uvideo_payload_header_t *hdr;
1728 	struct video_payload payload;
1729 
1730 	if (len < sizeof(uvideo_payload_header_t)) {
1731 		DPRINTF(("uvideo_stream_recv_process: len %d < payload hdr\n",
1732 			 len));
1733 		return USBD_SHORT_XFER;
1734 	}
1735 
1736 	hdr = (uvideo_payload_header_t *)buf;
1737 
1738 	if (hdr->bHeaderLength > UVIDEO_PAYLOAD_HEADER_SIZE ||
1739 	    hdr->bHeaderLength < sizeof(uvideo_payload_header_t))
1740 		return USBD_INVAL;
1741 	if (hdr->bHeaderLength == len && !(hdr->bmHeaderInfo & UV_END_OF_FRAME))
1742 		return USBD_INVAL;
1743 	if (hdr->bmHeaderInfo & UV_ERROR)
1744 		return USBD_IOERROR;
1745 
1746 	payload.data = buf + hdr->bHeaderLength;
1747 	payload.size = len - hdr->bHeaderLength;
1748 	payload.frameno = hdr->bmHeaderInfo & UV_FRAME_ID;
1749 	payload.end_of_frame = hdr->bmHeaderInfo & UV_END_OF_FRAME;
1750 
1751 	video_submit_payload(vs->vs_parent->sc_videodev, &payload);
1752 
1753 	return USBD_NORMAL_COMPLETION;
1754 }
1755 
1756 /* Callback on completion of usb isoc transfer */
1757 static void
1758 uvideo_stream_recv_isoc_complete(struct usbd_xfer *xfer,
1759 				 void *priv,
1760 				 usbd_status status)
1761 {
1762 	struct uvideo_stream *vs;
1763 	struct uvideo_isoc_xfer *ix;
1764 	struct uvideo_isoc *isoc;
1765 	int i;
1766 	uint32_t count;
1767 	uint8_t *buf;
1768 
1769 	isoc = priv;
1770 	vs = isoc->i_vs;
1771 	ix = isoc->i_ix;
1772 
1773 	if (status != USBD_NORMAL_COMPLETION) {
1774 		DPRINTF(("uvideo_stream_recv_isoc_complete: status=%s (%d)\n",
1775 			usbd_errstr(status), status));
1776 
1777 		if (status == USBD_STALLED)
1778 			usbd_clear_endpoint_stall_async(ix->ix_pipe);
1779 		else
1780 			return;
1781 	} else {
1782 		usbd_get_xfer_status(xfer, NULL, NULL, &count, NULL);
1783 
1784 		if (count == 0) {
1785 			/* DPRINTF(("uvideo: zero length transfer\n")); */
1786 			goto next;
1787 		}
1788 
1789 
1790 		for (i = 0, buf = isoc->i_buf;
1791 		     i < ix->ix_nframes;
1792 		     ++i, buf += ix->ix_uframe_len)
1793 		{
1794 			status = uvideo_stream_recv_process(vs, buf,
1795 			    isoc->i_frlengths[i]);
1796 			if (status == USBD_IOERROR)
1797 				break;
1798 		}
1799 	}
1800 
1801 next:
1802 	uvideo_stream_recv_isoc_start1(isoc);
1803 }
1804 
1805 static void
1806 uvideo_stream_recv_bulk_transfer(void *addr)
1807 {
1808 	struct uvideo_stream *vs = addr;
1809 	struct uvideo_bulk_xfer *bx = &vs->vs_xfer.bulk;
1810 	usbd_status err;
1811 	uint32_t len;
1812 
1813 	DPRINTF(("uvideo_stream_recv_bulk_transfer: "
1814 		 "vs %p sc %p bx %p buffer %p\n", vs, vs->vs_parent, bx,
1815 		 bx->bx_buffer));
1816 
1817 	while (bx->bx_running) {
1818 		len = bx->bx_buflen;
1819 		err = usbd_bulk_transfer(bx->bx_xfer, bx->bx_pipe,
1820 		    USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT,
1821 		    bx->bx_buffer, &len);
1822 
1823 		if (err == USBD_NORMAL_COMPLETION) {
1824 			uvideo_stream_recv_process(vs, bx->bx_buffer, len);
1825 		} else {
1826 			DPRINTF(("uvideo_stream_recv_bulk_transfer: %s\n",
1827 				 usbd_errstr(err)));
1828 		}
1829 	}
1830 
1831 	DPRINTF(("uvideo_stream_recv_bulk_transfer: notify complete\n"));
1832 
1833 	mutex_enter(&bx->bx_lock);
1834 	cv_broadcast(&bx->bx_cv);
1835 	mutex_exit(&bx->bx_lock);
1836 
1837 	DPRINTF(("uvideo_stream_recv_bulk_transfer: return\n"));
1838 
1839 	kthread_exit(0);
1840 }
1841 
1842 /*
1843  * uvideo_open - probe and commit video format and start receiving
1844  * video data
1845  */
1846 static int
1847 uvideo_open(void *addr, int flags)
1848 {
1849 	struct uvideo_softc *sc;
1850 	struct uvideo_stream *vs;
1851 	struct video_format fmt;
1852 
1853 	sc = addr;
1854 	vs = sc->sc_stream_in;
1855 
1856 	DPRINTF(("uvideo_open: sc=%p\n", sc));
1857 	if (sc->sc_dying)
1858 		return EIO;
1859 
1860 	/* XXX select default format */
1861 	fmt = *vs->vs_default_format;
1862 	return uvideo_set_format(addr, &fmt);
1863 }
1864 
1865 
1866 static void
1867 uvideo_close(void *addr)
1868 {
1869 	struct uvideo_softc *sc;
1870 
1871 	sc = addr;
1872 
1873 	if (sc->sc_state != UVIDEO_STATE_CLOSED) {
1874 		sc->sc_state = UVIDEO_STATE_CLOSED;
1875 	}
1876 }
1877 
1878 static const char *
1879 uvideo_get_devname(void *addr)
1880 {
1881 	struct uvideo_softc *sc = addr;
1882 	return sc->sc_devname;
1883 }
1884 
1885 static const char *
1886 uvideo_get_businfo(void *addr)
1887 {
1888 	struct uvideo_softc *sc = addr;
1889 	return sc->sc_businfo;
1890 }
1891 
1892 static int
1893 uvideo_enum_format(void *addr, uint32_t index, struct video_format *format)
1894 {
1895 	struct uvideo_softc *sc = addr;
1896 	struct uvideo_stream *vs = sc->sc_stream_in;
1897 	struct uvideo_pixel_format *pixel_format;
1898 	int off;
1899 
1900 	if (sc->sc_dying)
1901 		return EIO;
1902 
1903 	off = 0;
1904 	SIMPLEQ_FOREACH(pixel_format, &vs->vs_pixel_formats, entries) {
1905 		if (off++ != index)
1906 			continue;
1907 		format->pixel_format = pixel_format->pixel_format;
1908 		return 0;
1909 	}
1910 
1911 	return EINVAL;
1912 }
1913 
1914 /*
1915  * uvideo_get_format
1916  */
1917 static int
1918 uvideo_get_format(void *addr, struct video_format *format)
1919 {
1920 	struct uvideo_softc *sc = addr;
1921 	struct uvideo_stream *vs = sc->sc_stream_in;
1922 
1923 	if (sc->sc_dying)
1924 		return EIO;
1925 
1926 	*format = vs->vs_current_format;
1927 
1928 	return 0;
1929 }
1930 
1931 /*
1932  * uvideo_set_format - TODO: this is broken and does nothing
1933  */
1934 static int
1935 uvideo_set_format(void *addr, struct video_format *format)
1936 {
1937 	struct uvideo_softc *sc;
1938 	struct uvideo_stream *vs;
1939 	struct uvideo_format *uvfmt;
1940 	uvideo_probe_and_commit_data_t probe, maxprobe;
1941 	usbd_status err;
1942 
1943 	sc = addr;
1944 
1945 	DPRINTF(("uvideo_set_format: sc=%p\n", sc));
1946 	if (sc->sc_dying)
1947 		return EIO;
1948 
1949 	vs = sc->sc_stream_in;
1950 
1951 	uvfmt =	uvideo_stream_guess_format(vs, format->pixel_format,
1952 					   format->width, format->height);
1953 	if (uvfmt == NULL) {
1954 		DPRINTF(("uvideo: uvideo_stream_guess_format couldn't find "
1955 			 "%dx%d format %d\n", format->width, format->height,
1956 			 format->pixel_format));
1957 		return EINVAL;
1958 	}
1959 
1960 	uvideo_init_probe_data(&probe);
1961 	probe.bFormatIndex = UVIDEO_FORMAT_GET_FORMAT_INDEX(uvfmt);
1962 	probe.bFrameIndex = UVIDEO_FORMAT_GET_FRAME_INDEX(uvfmt);
1963 	USETDW(probe.dwFrameInterval, vs->vs_frame_interval);	/* XXX */
1964 
1965 	maxprobe = probe;
1966 	err = uvideo_stream_probe(vs, UR_GET_MAX, &maxprobe);
1967 	if (err) {
1968 		DPRINTF(("uvideo: error probe/GET_MAX: %s (%d)\n",
1969 			 usbd_errstr(err), err));
1970 	} else {
1971 		USETW(probe.wCompQuality, UGETW(maxprobe.wCompQuality));
1972 	}
1973 
1974 	err = uvideo_stream_probe(vs, UR_SET_CUR, &probe);
1975 	if (err) {
1976 		DPRINTF(("uvideo: error commit/SET_CUR: %s (%d)\n",
1977 			 usbd_errstr(err), err));
1978 		return EIO;
1979 	}
1980 
1981 	uvideo_init_probe_data(&probe);
1982 	err = uvideo_stream_probe(vs, UR_GET_CUR, &probe);
1983 	if (err) {
1984 		DPRINTF(("uvideo: error commit/SET_CUR: %s (%d)\n",
1985 			 usbd_errstr(err), err));
1986 		return EIO;
1987 	}
1988 
1989 	if (probe.bFormatIndex != UVIDEO_FORMAT_GET_FORMAT_INDEX(uvfmt)) {
1990 		DPRINTF(("uvideo: probe/GET_CUR returned format index %d "
1991 			 "(expected %d)\n", probe.bFormatIndex,
1992 			 UVIDEO_FORMAT_GET_FORMAT_INDEX(uvfmt)));
1993 		probe.bFormatIndex = UVIDEO_FORMAT_GET_FORMAT_INDEX(uvfmt);
1994 	}
1995 	if (probe.bFrameIndex != UVIDEO_FORMAT_GET_FRAME_INDEX(uvfmt)) {
1996 		DPRINTF(("uvideo: probe/GET_CUR returned frame index %d "
1997 			 "(expected %d)\n", probe.bFrameIndex,
1998 			 UVIDEO_FORMAT_GET_FRAME_INDEX(uvfmt)));
1999 		probe.bFrameIndex = UVIDEO_FORMAT_GET_FRAME_INDEX(uvfmt);
2000 	}
2001 	USETDW(probe.dwFrameInterval, vs->vs_frame_interval);	/* XXX */
2002 
2003 	/* commit/SET_CUR. Fourth step is to set the alternate
2004 	 * interface.  Currently the fourth step is in
2005 	 * uvideo_start_transfer.  Maybe move it here? */
2006 	err = uvideo_stream_commit(vs, UR_SET_CUR, &probe);
2007 	if (err) {
2008 		DPRINTF(("uvideo: error commit/SET_CUR: %s (%d)\n",
2009 			 usbd_errstr(err), err));
2010 		return EIO;
2011 	}
2012 
2013 	DPRINTFN(15, ("uvideo_set_format: committing to format: "
2014 		      "bmHint=0x%04x bFormatIndex=%d bFrameIndex=%d "
2015 		      "dwFrameInterval=%u wKeyFrameRate=%d wPFrameRate=%d "
2016 		      "wCompQuality=%d wCompWindowSize=%d wDelay=%d "
2017 		      "dwMaxVideoFrameSize=%u dwMaxPayloadTransferSize=%u",
2018 		      UGETW(probe.bmHint),
2019 		      probe.bFormatIndex,
2020 		      probe.bFrameIndex,
2021 		      UGETDW(probe.dwFrameInterval),
2022 		      UGETW(probe.wKeyFrameRate),
2023 		      UGETW(probe.wPFrameRate),
2024 		      UGETW(probe.wCompQuality),
2025 		      UGETW(probe.wCompWindowSize),
2026 		      UGETW(probe.wDelay),
2027 		      UGETDW(probe.dwMaxVideoFrameSize),
2028 		      UGETDW(probe.dwMaxPayloadTransferSize)));
2029 	if (vs->vs_probelen == 34) {
2030 		DPRINTFN(15, (" dwClockFrequency=%u bmFramingInfo=0x%02x "
2031 			      "bPreferedVersion=%d bMinVersion=%d "
2032 			      "bMaxVersion=%d",
2033 			      UGETDW(probe.dwClockFrequency),
2034 			      probe.bmFramingInfo,
2035 			      probe.bPreferedVersion,
2036 			      probe.bMinVersion,
2037 			      probe.bMaxVersion));
2038 	}
2039 	DPRINTFN(15, ("\n"));
2040 
2041 	vs->vs_frame_interval = UGETDW(probe.dwFrameInterval);
2042 	vs->vs_max_payload_size = UGETDW(probe.dwMaxPayloadTransferSize);
2043 
2044 	*format = uvfmt->format;
2045 	vs->vs_current_format = *format;
2046 	DPRINTF(("uvideo_set_format: pixeltype is %d\n", format->pixel_format));
2047 
2048 	return 0;
2049 }
2050 
2051 static int
2052 uvideo_try_format(void *addr, struct video_format *format)
2053 {
2054 	struct uvideo_softc *sc = addr;
2055 	struct uvideo_stream *vs = sc->sc_stream_in;
2056 	struct uvideo_format *uvfmt;
2057 
2058 	uvfmt =	uvideo_stream_guess_format(vs, format->pixel_format,
2059 					   format->width, format->height);
2060 	if (uvfmt == NULL)
2061 		return EINVAL;
2062 
2063 	*format = uvfmt->format;
2064 	return 0;
2065 }
2066 
2067 static int
2068 uvideo_start_transfer(void *addr)
2069 {
2070 	struct uvideo_softc *sc = addr;
2071 	struct uvideo_stream *vs;
2072 	int s, err;
2073 
2074 	/* FIXME: this function should be stream specific */
2075 	vs = SLIST_FIRST(&sc->sc_stream_list);
2076 	s = splusb();
2077 	err = uvideo_stream_start_xfer(vs);
2078 	splx(s);
2079 
2080 	return err;
2081 }
2082 
2083 static int
2084 uvideo_stop_transfer(void *addr)
2085 {
2086 	struct uvideo_softc *sc;
2087 	int err, s;
2088 
2089 	sc = addr;
2090 
2091 	s = splusb();
2092 	err = uvideo_stream_stop_xfer(sc->sc_stream_in);
2093 	splx(s);
2094 
2095 	return err;
2096 }
2097 
2098 
2099 static int
2100 uvideo_get_control_group(void *addr, struct video_control_group *group)
2101 {
2102 	struct uvideo_softc *sc;
2103 	usb_device_request_t req;
2104 	usbd_status err;
2105 	uint8_t control_id, ent_id, data[16];
2106 	uint16_t len;
2107 	int s;
2108 
2109 	sc = addr;
2110 
2111 	/* request setup */
2112 	switch (group->group_id) {
2113 	case VIDEO_CONTROL_PANTILT_RELATIVE:
2114 		if (group->length != 4)
2115 			return EINVAL;
2116 
2117 		return EINVAL;
2118 	case VIDEO_CONTROL_SHARPNESS:
2119 		if (group->length != 1)
2120 			return EINVAL;
2121 
2122 		control_id = UVIDEO_PU_SHARPNESS_CONTROL;
2123 		ent_id = 2; /* TODO: hardcoded logitech processing unit */
2124 		len = 2;
2125 		break;
2126 	default:
2127 		return EINVAL;
2128 	}
2129 
2130 	/* do request */
2131 	req.bmRequestType = UVIDEO_REQUEST_TYPE_INTERFACE |
2132 	    UVIDEO_REQUEST_TYPE_CLASS_SPECIFIC |
2133 	    UVIDEO_REQUEST_TYPE_GET;
2134 	req.bRequest = UR_GET_CUR;
2135 	USETW(req.wValue, control_id << 8);
2136 	USETW(req.wIndex, (ent_id << 8) | sc->sc_ifaceno);
2137 	USETW(req.wLength, len);
2138 
2139 	s = splusb();
2140 	err = usbd_do_request(sc->sc_udev, &req, data);
2141 	splx(s);
2142 	if (err != USBD_NORMAL_COMPLETION) {
2143 		DPRINTF(("uvideo_set_control: error %s (%d)\n",
2144 			 usbd_errstr(err), err));
2145 		return EIO;	/* TODO: more detail here? */
2146 	}
2147 
2148 	/* extract request data */
2149 	switch (group->group_id) {
2150 	case VIDEO_CONTROL_SHARPNESS:
2151 		group->control[0].value = UGETW(data);
2152 		break;
2153 	default:
2154 		return EINVAL;
2155 	}
2156 
2157 	return 0;
2158 }
2159 
2160 
2161 static int
2162 uvideo_set_control_group(void *addr, const struct video_control_group *group)
2163 {
2164 	struct uvideo_softc *sc;
2165 	usb_device_request_t req;
2166 	usbd_status err;
2167 	uint8_t control_id, ent_id, data[16]; /* long enough for all controls */
2168 	uint16_t len;
2169 	int s;
2170 
2171 	sc = addr;
2172 
2173 	switch (group->group_id) {
2174 	case VIDEO_CONTROL_PANTILT_RELATIVE:
2175 		if (group->length != 4)
2176 			return EINVAL;
2177 
2178 		if (group->control[0].value != 0 ||
2179 		    group->control[0].value != 1 ||
2180 		    group->control[0].value != 0xff)
2181 			return ERANGE;
2182 
2183 		if (group->control[2].value != 0 ||
2184 		    group->control[2].value != 1 ||
2185 		    group->control[2].value != 0xff)
2186 			return ERANGE;
2187 
2188 		control_id = UVIDEO_CT_PANTILT_RELATIVE_CONTROL;
2189 		ent_id = 1;	/* TODO: hardcoded logitech camera terminal  */
2190 		len = 4;
2191 		data[0] = group->control[0].value;
2192 		data[1] = group->control[1].value;
2193 		data[2] = group->control[2].value;
2194 		data[3] = group->control[3].value;
2195 		break;
2196 	case VIDEO_CONTROL_BRIGHTNESS:
2197 		if (group->length != 1)
2198 			return EINVAL;
2199 		control_id = UVIDEO_PU_BRIGHTNESS_CONTROL;
2200 		ent_id = 2;
2201 		len = 2;
2202 		USETW(data, group->control[0].value);
2203 		break;
2204 	case VIDEO_CONTROL_GAIN:
2205 		if (group->length != 1)
2206 			return EINVAL;
2207 		control_id = UVIDEO_PU_GAIN_CONTROL;
2208 		ent_id = 2;
2209 		len = 2;
2210 		USETW(data, group->control[0].value);
2211 		break;
2212 	case VIDEO_CONTROL_SHARPNESS:
2213 		if (group->length != 1)
2214 			return EINVAL;
2215 		control_id = UVIDEO_PU_SHARPNESS_CONTROL;
2216 		ent_id = 2; /* TODO: hardcoded logitech processing unit */
2217 		len = 2;
2218 		USETW(data, group->control[0].value);
2219 		break;
2220 	default:
2221 		return EINVAL;
2222 	}
2223 
2224 	req.bmRequestType = UVIDEO_REQUEST_TYPE_INTERFACE |
2225 	    UVIDEO_REQUEST_TYPE_CLASS_SPECIFIC |
2226 	    UVIDEO_REQUEST_TYPE_SET;
2227 	req.bRequest = UR_SET_CUR;
2228 	USETW(req.wValue, control_id << 8);
2229 	USETW(req.wIndex, (ent_id << 8) | sc->sc_ifaceno);
2230 	USETW(req.wLength, len);
2231 
2232 	s = splusb();
2233 	err = usbd_do_request(sc->sc_udev, &req, data);
2234 	splx(s);
2235 	if (err != USBD_NORMAL_COMPLETION) {
2236 		DPRINTF(("uvideo_set_control: error %s (%d)\n",
2237 			 usbd_errstr(err), err));
2238 		return EIO;	/* TODO: more detail here? */
2239 	}
2240 
2241 	return 0;
2242 }
2243 
2244 static usbd_status
2245 uvideo_stream_probe_and_commit(struct uvideo_stream *vs,
2246 			       uint8_t action, uint8_t control,
2247 			       void *data)
2248 {
2249 	usb_device_request_t req;
2250 
2251 	switch (action) {
2252 	case UR_SET_CUR:
2253 		req.bmRequestType = UT_WRITE_CLASS_INTERFACE;
2254 		USETW(req.wLength, vs->vs_probelen);
2255 		break;
2256 	case UR_GET_CUR:
2257 	case UR_GET_MIN:
2258 	case UR_GET_MAX:
2259 	case UR_GET_DEF:
2260 		req.bmRequestType = UT_READ_CLASS_INTERFACE;
2261 		USETW(req.wLength, vs->vs_probelen);
2262 		break;
2263 	case UR_GET_INFO:
2264 		req.bmRequestType = UT_READ_CLASS_INTERFACE;
2265 		USETW(req.wLength, sizeof(uByte));
2266 		break;
2267 	case UR_GET_LEN:
2268 		req.bmRequestType = UT_READ_CLASS_INTERFACE;
2269 		USETW(req.wLength, sizeof(uWord)); /* is this right? */
2270 		break;
2271 	default:
2272 		DPRINTF(("uvideo_probe_and_commit: "
2273 			 "unknown request action %d\n", action));
2274 		return USBD_NOT_STARTED;
2275 	}
2276 
2277 	req.bRequest = action;
2278 	USETW2(req.wValue, control, 0);
2279 	USETW2(req.wIndex, 0, vs->vs_ifaceno);
2280 
2281 	return (usbd_do_request_flags(vs->vs_parent->sc_udev, &req, data,
2282 				      0, 0,
2283 				      USBD_DEFAULT_TIMEOUT));
2284 }
2285 
2286 static void
2287 uvideo_init_probe_data(uvideo_probe_and_commit_data_t *probe)
2288 {
2289 	/* all zeroes tells camera to choose what it wants */
2290 	memset(probe, 0, sizeof(*probe));
2291 }
2292 
2293 
2294 #ifdef _MODULE
2295 
2296 MODULE(MODULE_CLASS_DRIVER, uvideo, NULL);
2297 static const struct cfiattrdata videobuscf_iattrdata = {
2298         "videobus", 0, {
2299 		{ NULL, NULL, 0 },
2300 	}
2301 };
2302 static const struct cfiattrdata * const uvideo_attrs[] = {
2303 	&videobuscf_iattrdata, NULL
2304 };
2305 CFDRIVER_DECL(uvideo, DV_DULL, uvideo_attrs);
2306 extern struct cfattach uvideo_ca;
2307 extern struct cfattach uvideo_ca;
2308 static int uvideoloc[6] = { -1, -1, -1, -1, -1, -1 };
2309 static struct cfparent uhubparent = {
2310         "usbifif", NULL, DVUNIT_ANY
2311 };
2312 static struct cfdata uvideo_cfdata[] = {
2313 	{
2314 		.cf_name = "uvideo",
2315 		.cf_atname = "uvideo",
2316 		.cf_unit = 0,
2317 		.cf_fstate = FSTATE_STAR,
2318 		.cf_loc = uvideoloc,
2319 		.cf_flags = 0,
2320 		.cf_pspec = &uhubparent,
2321 	},
2322 	{ NULL, NULL, 0, 0, NULL, 0, NULL },
2323 };
2324 
2325 static int
2326 uvideo_modcmd(modcmd_t cmd, void *arg)
2327 {
2328 	int err;
2329 
2330 
2331 	switch (cmd) {
2332 	case MODULE_CMD_INIT:
2333 		DPRINTF(("uvideo: attempting to load\n"));
2334 
2335 		err = config_cfdriver_attach(&uvideo_cd);
2336 		if (err)
2337 			return err;
2338 		err = config_cfattach_attach("uvideo", &uvideo_ca);
2339 		if (err) {
2340 			config_cfdriver_detach(&uvideo_cd);
2341 			return err;
2342 		}
2343 		err = config_cfdata_attach(uvideo_cfdata, 1);
2344 		if (err) {
2345 			config_cfattach_detach("uvideo", &uvideo_ca);
2346 			config_cfdriver_detach(&uvideo_cd);
2347 			return err;
2348 		}
2349 		DPRINTF(("uvideo: loaded module\n"));
2350 		return 0;
2351 	case MODULE_CMD_FINI:
2352 		DPRINTF(("uvideo: attempting to unload module\n"));
2353 		err = config_cfdata_detach(uvideo_cfdata);
2354 		if (err)
2355 			return err;
2356 		config_cfattach_detach("uvideo", &uvideo_ca);
2357 		config_cfdriver_detach(&uvideo_cd);
2358 		DPRINTF(("uvideo: module unload\n"));
2359 		return 0;
2360 	default:
2361 		return ENOTTY;
2362 	}
2363 }
2364 
2365 #endif	/* _MODULE */
2366 
2367 
2368 #ifdef UVIDEO_DEBUG
2369 /* Some functions to print out descriptors.  Mostly useless other than
2370  * debugging/exploration purposes. */
2371 
2372 
2373 static void
2374 print_bitmap(const uByte *start, uByte nbytes)
2375 {
2376 	int byte, bit;
2377 
2378 	/* most significant first */
2379 	for (byte = nbytes-1; byte >= 0; --byte) {
2380 		if (byte < nbytes-1) printf("-");
2381 		for (bit = 7; bit >= 0; --bit)
2382 			printf("%01d", (start[byte] >> bit) &1);
2383 	}
2384 }
2385 
2386 static void
2387 print_descriptor(const usb_descriptor_t *desc)
2388 {
2389 	static int current_class = -1;
2390 	static int current_subclass = -1;
2391 
2392 	if (desc->bDescriptorType == UDESC_INTERFACE) {
2393 		const usb_interface_descriptor_t *id;
2394 		id = (const usb_interface_descriptor_t *)desc;
2395 		current_class = id->bInterfaceClass;
2396 		current_subclass = id->bInterfaceSubClass;
2397 		print_interface_descriptor(id);
2398 		printf("\n");
2399 		return;
2400 	}
2401 
2402 	printf("  ");		/* indent */
2403 
2404 	if (current_class == UICLASS_VIDEO) {
2405 		switch (current_subclass) {
2406 		case UISUBCLASS_VIDEOCONTROL:
2407 			print_vc_descriptor(desc);
2408 			break;
2409 		case UISUBCLASS_VIDEOSTREAMING:
2410 			print_vs_descriptor(desc);
2411 			break;
2412 		case UISUBCLASS_VIDEOCOLLECTION:
2413 			printf("uvc collection: len=%d type=0x%02x",
2414 			    desc->bLength, desc->bDescriptorType);
2415 			break;
2416 		}
2417 	} else {
2418 		printf("non uvc descriptor len=%d type=0x%02x",
2419 		    desc->bLength, desc->bDescriptorType);
2420 	}
2421 
2422 	printf("\n");
2423 }
2424 
2425 static void
2426 print_vc_descriptor(const usb_descriptor_t *desc)
2427 {
2428 	const uvideo_descriptor_t *vcdesc;
2429 
2430 	printf("VC ");
2431 
2432 	switch (desc->bDescriptorType) {
2433 	case UDESC_ENDPOINT:
2434 		print_endpoint_descriptor(
2435 			(const usb_endpoint_descriptor_t *)desc);
2436 		break;
2437 	case UDESC_CS_INTERFACE:
2438 		vcdesc = (const uvideo_descriptor_t *)desc;
2439 		switch (vcdesc->bDescriptorSubtype) {
2440 		case UDESC_VC_HEADER:
2441 			print_vc_header_descriptor(
2442 			  (const uvideo_vc_header_descriptor_t *)
2443 				vcdesc);
2444 			break;
2445 		case UDESC_INPUT_TERMINAL:
2446 			switch (UGETW(
2447 			   ((const uvideo_input_terminal_descriptor_t *)
2448 				    vcdesc)->wTerminalType)) {
2449 			case UVIDEO_ITT_CAMERA:
2450 				print_camera_terminal_descriptor(
2451 			  (const uvideo_camera_terminal_descriptor_t *)vcdesc);
2452 				break;
2453 			default:
2454 				print_input_terminal_descriptor(
2455 			  (const uvideo_input_terminal_descriptor_t *)vcdesc);
2456 				break;
2457 			}
2458 			break;
2459 		case UDESC_OUTPUT_TERMINAL:
2460 			print_output_terminal_descriptor(
2461 				(const uvideo_output_terminal_descriptor_t *)
2462 				vcdesc);
2463 			break;
2464 		case UDESC_SELECTOR_UNIT:
2465 			print_selector_unit_descriptor(
2466 				(const uvideo_selector_unit_descriptor_t *)
2467 				vcdesc);
2468 			break;
2469 		case UDESC_PROCESSING_UNIT:
2470 			print_processing_unit_descriptor(
2471 				(const uvideo_processing_unit_descriptor_t *)
2472 				vcdesc);
2473 			break;
2474 		case UDESC_EXTENSION_UNIT:
2475 			print_extension_unit_descriptor(
2476 				(const uvideo_extension_unit_descriptor_t *)
2477 				vcdesc);
2478 			break;
2479 		default:
2480 			printf("class specific interface "
2481 			    "len=%d type=0x%02x subtype=0x%02x",
2482 			    vcdesc->bLength,
2483 			    vcdesc->bDescriptorType,
2484 			    vcdesc->bDescriptorSubtype);
2485 			break;
2486 		}
2487 		break;
2488 	case UDESC_CS_ENDPOINT:
2489 		vcdesc = (const uvideo_descriptor_t *)desc;
2490 		switch (vcdesc->bDescriptorSubtype) {
2491 		case UDESC_VC_INTERRUPT_ENDPOINT:
2492 			print_interrupt_endpoint_descriptor(
2493 			    (const uvideo_vc_interrupt_endpoint_descriptor_t *)
2494 				vcdesc);
2495 			break;
2496 		default:
2497 			printf("class specific endpoint "
2498 			    "len=%d type=0x%02x subtype=0x%02x",
2499 			    vcdesc->bLength,
2500 			    vcdesc->bDescriptorType,
2501 			    vcdesc->bDescriptorSubtype);
2502 			break;
2503 		}
2504 		break;
2505 	default:
2506 		printf("unknown: len=%d type=0x%02x",
2507 		    desc->bLength, desc->bDescriptorType);
2508 		break;
2509 	}
2510 }
2511 
2512 static void
2513 print_vs_descriptor(const usb_descriptor_t *desc)
2514 {
2515 	const uvideo_descriptor_t * vsdesc;
2516 	printf("VS ");
2517 
2518 	switch (desc->bDescriptorType) {
2519 	case UDESC_ENDPOINT:
2520 		print_endpoint_descriptor(
2521 			(const usb_endpoint_descriptor_t *)desc);
2522 		break;
2523 	case UDESC_CS_INTERFACE:
2524 		vsdesc = (const uvideo_descriptor_t *)desc;
2525 		switch (vsdesc->bDescriptorSubtype) {
2526 		case UDESC_VS_INPUT_HEADER:
2527 			print_vs_input_header_descriptor(
2528 			 (const uvideo_vs_input_header_descriptor_t *)
2529 				vsdesc);
2530 			break;
2531 		case UDESC_VS_OUTPUT_HEADER:
2532 			print_vs_output_header_descriptor(
2533 			(const uvideo_vs_output_header_descriptor_t *)
2534 				vsdesc);
2535 			break;
2536 		case UDESC_VS_FORMAT_UNCOMPRESSED:
2537 			print_vs_format_uncompressed_descriptor(
2538 			   (const uvideo_vs_format_uncompressed_descriptor_t *)
2539 				vsdesc);
2540 			break;
2541 		case UDESC_VS_FRAME_UNCOMPRESSED:
2542 			print_vs_frame_uncompressed_descriptor(
2543 			    (const uvideo_vs_frame_uncompressed_descriptor_t *)
2544 				vsdesc);
2545 			break;
2546 		case UDESC_VS_FORMAT_MJPEG:
2547 			print_vs_format_mjpeg_descriptor(
2548 				(const uvideo_vs_format_mjpeg_descriptor_t *)
2549 				vsdesc);
2550 			break;
2551 		case UDESC_VS_FRAME_MJPEG:
2552 			print_vs_frame_mjpeg_descriptor(
2553 				(const uvideo_vs_frame_mjpeg_descriptor_t *)
2554 				vsdesc);
2555 			break;
2556 		case UDESC_VS_FORMAT_DV:
2557 			print_vs_format_dv_descriptor(
2558 				(const uvideo_vs_format_dv_descriptor_t *)
2559 				vsdesc);
2560 			break;
2561 		default:
2562 			printf("unknown cs interface: len=%d type=0x%02x "
2563 			    "subtype=0x%02x",
2564 			    vsdesc->bLength, vsdesc->bDescriptorType,
2565 			    vsdesc->bDescriptorSubtype);
2566 		}
2567 		break;
2568 	default:
2569 		printf("unknown: len=%d type=0x%02x",
2570 		    desc->bLength, desc->bDescriptorType);
2571 		break;
2572 	}
2573 }
2574 
2575 static void
2576 print_interface_descriptor(const usb_interface_descriptor_t *id)
2577 {
2578 	printf("Interface: Len=%d Type=0x%02x "
2579 	    "bInterfaceNumber=0x%02x "
2580 	    "bAlternateSetting=0x%02x bNumEndpoints=0x%02x "
2581 	    "bInterfaceClass=0x%02x bInterfaceSubClass=0x%02x "
2582 	    "bInterfaceProtocol=0x%02x iInterface=0x%02x",
2583 	    id->bLength,
2584 	    id->bDescriptorType,
2585 	    id->bInterfaceNumber,
2586 	    id->bAlternateSetting,
2587 	    id->bNumEndpoints,
2588 	    id->bInterfaceClass,
2589 	    id->bInterfaceSubClass,
2590 	    id->bInterfaceProtocol,
2591 	    id->iInterface);
2592 }
2593 
2594 static void
2595 print_endpoint_descriptor(const usb_endpoint_descriptor_t *desc)
2596 {
2597 	printf("Endpoint: Len=%d Type=0x%02x "
2598 	    "bEndpointAddress=0x%02x ",
2599 	    desc->bLength,
2600 	    desc->bDescriptorType,
2601 	    desc->bEndpointAddress);
2602 	printf("bmAttributes=");
2603 	print_bitmap(&desc->bmAttributes, 1);
2604 	printf(" wMaxPacketSize=%d bInterval=%d",
2605 	    UGETW(desc->wMaxPacketSize),
2606 	    desc->bInterval);
2607 }
2608 
2609 static void
2610 print_vc_header_descriptor(
2611 	const uvideo_vc_header_descriptor_t *desc)
2612 {
2613 	printf("Interface Header: "
2614 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2615 	    "bcdUVC=%d wTotalLength=%d "
2616 	    "dwClockFrequency=%u bInCollection=%d",
2617 	    desc->bLength,
2618 	    desc->bDescriptorType,
2619 	    desc->bDescriptorSubtype,
2620 	    UGETW(desc->bcdUVC),
2621 	    UGETW(desc->wTotalLength),
2622 	    UGETDW(desc->dwClockFrequency),
2623 	    desc->bInCollection);
2624 }
2625 
2626 static void
2627 print_input_terminal_descriptor(
2628 	const uvideo_input_terminal_descriptor_t *desc)
2629 {
2630 	printf("Input Terminal: "
2631 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2632 	    "bTerminalID=%d wTerminalType=%x bAssocTerminal=%d "
2633 	    "iTerminal=%d",
2634 	    desc->bLength,
2635 	    desc->bDescriptorType,
2636 	    desc->bDescriptorSubtype,
2637 	    desc->bTerminalID,
2638 	    UGETW(desc->wTerminalType),
2639 	    desc->bAssocTerminal,
2640 	    desc->iTerminal);
2641 }
2642 
2643 static void
2644 print_output_terminal_descriptor(
2645 	const uvideo_output_terminal_descriptor_t *desc)
2646 {
2647 	printf("Output Terminal: "
2648 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2649 	    "bTerminalID=%d wTerminalType=%x bAssocTerminal=%d "
2650 	    "bSourceID=%d iTerminal=%d",
2651 	    desc->bLength,
2652 	    desc->bDescriptorType,
2653 	    desc->bDescriptorSubtype,
2654 	    desc->bTerminalID,
2655 	    UGETW(desc->wTerminalType),
2656 	    desc->bAssocTerminal,
2657 	    desc->bSourceID,
2658 	    desc->iTerminal);
2659 }
2660 
2661 static void
2662 print_camera_terminal_descriptor(
2663 	const uvideo_camera_terminal_descriptor_t *desc)
2664 {
2665 	printf("Camera Terminal: "
2666 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2667 	    "bTerminalID=%d wTerminalType=%x bAssocTerminal=%d "
2668 	    "iTerminal=%d "
2669 	    "wObjectiveFocalLengthMin/Max=%d/%d "
2670 	    "wOcularFocalLength=%d "
2671 	    "bControlSize=%d ",
2672 	    desc->bLength,
2673 	    desc->bDescriptorType,
2674 	    desc->bDescriptorSubtype,
2675 	    desc->bTerminalID,
2676 	    UGETW(desc->wTerminalType),
2677 	    desc->bAssocTerminal,
2678 	    desc->iTerminal,
2679 	    UGETW(desc->wObjectiveFocalLengthMin),
2680 	    UGETW(desc->wObjectiveFocalLengthMax),
2681 	    UGETW(desc->wOcularFocalLength),
2682 	    desc->bControlSize);
2683 	printf("bmControls=");
2684 	print_bitmap(desc->bmControls, desc->bControlSize);
2685 }
2686 
2687 static void
2688 print_selector_unit_descriptor(
2689 	const uvideo_selector_unit_descriptor_t *desc)
2690 {
2691 	int i;
2692 	const uByte *b;
2693 	printf("Selector Unit: "
2694 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2695 	    "bUnitID=%d bNrInPins=%d ",
2696 	    desc->bLength,
2697 	    desc->bDescriptorType,
2698 	    desc->bDescriptorSubtype,
2699 	    desc->bUnitID,
2700 	    desc->bNrInPins);
2701 	printf("baSourceIDs=");
2702 	b = &desc->baSourceID[0];
2703 	for (i = 0; i < desc->bNrInPins; ++i)
2704 		printf("%d ", *b++);
2705 	printf("iSelector=%d", *b);
2706 }
2707 
2708 static void
2709 print_processing_unit_descriptor(
2710 	const uvideo_processing_unit_descriptor_t *desc)
2711 {
2712 	const uByte *b;
2713 
2714 	printf("Processing Unit: "
2715 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2716 	    "bUnitID=%d bSourceID=%d wMaxMultiplier=%d bControlSize=%d ",
2717 	    desc->bLength,
2718 	    desc->bDescriptorType,
2719 	    desc->bDescriptorSubtype,
2720 	    desc->bUnitID,
2721 	    desc->bSourceID,
2722 	    UGETW(desc->wMaxMultiplier),
2723 	    desc->bControlSize);
2724 	printf("bmControls=");
2725 	print_bitmap(desc->bmControls, desc->bControlSize);
2726 	b = &desc->bControlSize + desc->bControlSize + 1;
2727 	printf(" iProcessing=%d bmVideoStandards=", *b);
2728 	b += 1;
2729 	print_bitmap(b, 1);
2730 }
2731 
2732 static void
2733 print_extension_unit_descriptor(
2734 	const uvideo_extension_unit_descriptor_t *desc)
2735 {
2736 	const uByte * byte;
2737 	uByte controlbytes;
2738 	int i;
2739 
2740 	printf("Extension Unit: "
2741 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2742 	    "bUnitID=%d ",
2743 	    desc->bLength,
2744 	    desc->bDescriptorType,
2745 	    desc->bDescriptorSubtype,
2746 	    desc->bUnitID);
2747 
2748 	printf("guidExtensionCode=");
2749 	usb_guid_print(&desc->guidExtensionCode);
2750 	printf(" ");
2751 
2752 	printf("bNumControls=%d bNrInPins=%d ",
2753 	    desc->bNumControls,
2754 	    desc->bNrInPins);
2755 
2756 	printf("baSourceIDs=");
2757 	byte = &desc->baSourceID[0];
2758 	for (i = 0; i < desc->bNrInPins; ++i)
2759 		printf("%d ", *byte++);
2760 
2761 	controlbytes = *byte++;
2762 	printf("bControlSize=%d ", controlbytes);
2763 	printf("bmControls=");
2764 	print_bitmap(byte, controlbytes);
2765 
2766 	byte += controlbytes;
2767 	printf(" iExtension=%d", *byte);
2768 }
2769 
2770 static void
2771 print_interrupt_endpoint_descriptor(
2772 	const uvideo_vc_interrupt_endpoint_descriptor_t *desc)
2773 {
2774 	printf("Interrupt Endpoint: "
2775 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2776 	    "wMaxTransferSize=%d ",
2777 	    desc->bLength,
2778 	    desc->bDescriptorType,
2779 	    desc->bDescriptorSubtype,
2780 	    UGETW(desc->wMaxTransferSize));
2781 }
2782 
2783 
2784 static void
2785 print_vs_output_header_descriptor(
2786 	const uvideo_vs_output_header_descriptor_t *desc)
2787 {
2788 	printf("Interface Output Header: "
2789 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2790 	    "bNumFormats=%d wTotalLength=%d bEndpointAddress=%d "
2791 	    "bTerminalLink=%d bControlSize=%d",
2792 	    desc->bLength,
2793 	    desc->bDescriptorType,
2794 	    desc->bDescriptorSubtype,
2795 	    desc->bNumFormats,
2796 	    UGETW(desc->wTotalLength),
2797 	    desc->bEndpointAddress,
2798 	    desc->bTerminalLink,
2799 	    desc->bControlSize);
2800 }
2801 
2802 static void
2803 print_vs_input_header_descriptor(
2804 	const uvideo_vs_input_header_descriptor_t *desc)
2805 {
2806 	printf("Interface Input Header: "
2807 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2808 	    "bNumFormats=%d wTotalLength=%d bEndpointAddress=%d "
2809 	    "bmInfo=%x bTerminalLink=%d bStillCaptureMethod=%d "
2810 	    "bTriggerSupport=%d bTriggerUsage=%d bControlSize=%d ",
2811 	    desc->bLength,
2812 	    desc->bDescriptorType,
2813 	    desc->bDescriptorSubtype,
2814 	    desc->bNumFormats,
2815 	    UGETW(desc->wTotalLength),
2816 	    desc->bEndpointAddress,
2817 	    desc->bmInfo,
2818 	    desc->bTerminalLink,
2819 	    desc->bStillCaptureMethod,
2820 	    desc->bTriggerSupport,
2821 	    desc->bTriggerUsage,
2822 	    desc->bControlSize);
2823 	print_bitmap(desc->bmaControls, desc->bControlSize);
2824 }
2825 
2826 static void
2827 print_vs_format_uncompressed_descriptor(
2828 	const uvideo_vs_format_uncompressed_descriptor_t *desc)
2829 {
2830 	printf("Format Uncompressed: "
2831 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2832 	    "bFormatIndex=%d bNumFrameDescriptors=%d ",
2833 	    desc->bLength,
2834 	    desc->bDescriptorType,
2835 	    desc->bDescriptorSubtype,
2836 	    desc->bFormatIndex,
2837 	    desc->bNumFrameDescriptors);
2838 	usb_guid_print(&desc->guidFormat);
2839 	printf(" bBitsPerPixel=%d bDefaultFrameIndex=%d "
2840 	    "bAspectRatioX=%d bAspectRatioY=%d "
2841 	    "bmInterlaceFlags=0x%02x bCopyProtect=%d",
2842 	    desc->bBitsPerPixel,
2843 	    desc->bDefaultFrameIndex,
2844 	    desc->bAspectRatioX,
2845 	    desc->bAspectRatioY,
2846 	    desc->bmInterlaceFlags,
2847 	    desc->bCopyProtect);
2848 }
2849 
2850 static void
2851 print_vs_frame_uncompressed_descriptor(
2852 	const uvideo_vs_frame_uncompressed_descriptor_t *desc)
2853 {
2854 	printf("Frame Uncompressed: "
2855 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2856 	    "bFrameIndex=%d bmCapabilities=0x%02x "
2857 	    "wWidth=%d wHeight=%d dwMinBitRate=%u dwMaxBitRate=%u "
2858 	    "dwMaxVideoFrameBufferSize=%u dwDefaultFrameInterval=%u "
2859 	    "bFrameIntervalType=%d",
2860 	    desc->bLength,
2861 	    desc->bDescriptorType,
2862 	    desc->bDescriptorSubtype,
2863 	    desc->bFrameIndex,
2864 	    desc->bmCapabilities,
2865 	    UGETW(desc->wWidth),
2866 	    UGETW(desc->wHeight),
2867 	    UGETDW(desc->dwMinBitRate),
2868 	    UGETDW(desc->dwMaxBitRate),
2869 	    UGETDW(desc->dwMaxVideoFrameBufferSize),
2870 	    UGETDW(desc->dwDefaultFrameInterval),
2871 	    desc->bFrameIntervalType);
2872 }
2873 
2874 static void
2875 print_vs_format_mjpeg_descriptor(
2876 	const uvideo_vs_format_mjpeg_descriptor_t *desc)
2877 {
2878 	printf("MJPEG format: "
2879 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2880 	    "bFormatIndex=%d bNumFrameDescriptors=%d bmFlags=0x%02x "
2881 	    "bDefaultFrameIndex=%d bAspectRatioX=%d bAspectRatioY=%d "
2882 	    "bmInterlaceFlags=0x%02x bCopyProtect=%d",
2883 	    desc->bLength,
2884 	    desc->bDescriptorType,
2885 	    desc->bDescriptorSubtype,
2886 	    desc->bFormatIndex,
2887 	    desc->bNumFrameDescriptors,
2888 	    desc->bmFlags,
2889 	    desc->bDefaultFrameIndex,
2890 	    desc->bAspectRatioX,
2891 	    desc->bAspectRatioY,
2892 	    desc->bmInterlaceFlags,
2893 	    desc->bCopyProtect);
2894 }
2895 
2896 static void
2897 print_vs_frame_mjpeg_descriptor(
2898 	const uvideo_vs_frame_mjpeg_descriptor_t *desc)
2899 {
2900 	printf("MJPEG frame: "
2901 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2902 	    "bFrameIndex=%d bmCapabilities=0x%02x "
2903 	    "wWidth=%d wHeight=%d dwMinBitRate=%u dwMaxBitRate=%u "
2904 	    "dwMaxVideoFrameBufferSize=%u dwDefaultFrameInterval=%u "
2905 	    "bFrameIntervalType=%d",
2906 	    desc->bLength,
2907 	    desc->bDescriptorType,
2908 	    desc->bDescriptorSubtype,
2909 	    desc->bFrameIndex,
2910 	    desc->bmCapabilities,
2911 	    UGETW(desc->wWidth),
2912 	    UGETW(desc->wHeight),
2913 	    UGETDW(desc->dwMinBitRate),
2914 	    UGETDW(desc->dwMaxBitRate),
2915 	    UGETDW(desc->dwMaxVideoFrameBufferSize),
2916 	    UGETDW(desc->dwDefaultFrameInterval),
2917 	    desc->bFrameIntervalType);
2918 }
2919 
2920 static void
2921 print_vs_format_dv_descriptor(
2922 	const uvideo_vs_format_dv_descriptor_t *desc)
2923 {
2924 	printf("MJPEG format: "
2925 	    "Len=%d Type=0x%02x Subtype=0x%02x "
2926 	    "bFormatIndex=%d dwMaxVideoFrameBufferSize=%u "
2927 	    "bFormatType/Rate=%d bFormatType/Format=%d",
2928 	    desc->bLength,
2929 	    desc->bDescriptorType,
2930 	    desc->bDescriptorSubtype,
2931 	    desc->bFormatIndex,
2932 	    UGETDW(desc->dwMaxVideoFrameBufferSize),
2933 	    UVIDEO_GET_DV_FREQ(desc->bFormatType),
2934 	    UVIDEO_GET_DV_FORMAT(desc->bFormatType));
2935 }
2936 
2937 #endif /* !UVIDEO_DEBUG */
2938 
2939 static const usb_descriptor_t *
2940 usb_desc_iter_peek_next(usbd_desc_iter_t *iter)
2941 {
2942         const usb_descriptor_t *desc;
2943 
2944         if (iter->cur + sizeof(usb_descriptor_t) >= iter->end) {
2945                 if (iter->cur != iter->end)
2946                         printf("usb_desc_iter_peek_next: bad descriptor\n");
2947                 return NULL;
2948         }
2949         desc = (const usb_descriptor_t *)iter->cur;
2950         if (desc->bLength == 0) {
2951                 printf("usb_desc_iter_peek_next: descriptor length = 0\n");
2952                 return NULL;
2953         }
2954         if (iter->cur + desc->bLength > iter->end) {
2955                 printf("usb_desc_iter_peek_next: descriptor length too large\n");
2956                 return NULL;
2957         }
2958         return desc;
2959 }
2960 
2961 /* Return the next interface descriptor, skipping over any other
2962  * descriptors.  Returns NULL at the end or on error. */
2963 static const usb_interface_descriptor_t *
2964 usb_desc_iter_next_interface(usbd_desc_iter_t *iter)
2965 {
2966 	const usb_descriptor_t *desc;
2967 
2968 	while ((desc = usb_desc_iter_peek_next(iter)) != NULL &&
2969 	       desc->bDescriptorType != UDESC_INTERFACE)
2970 	{
2971 		usb_desc_iter_next(iter);
2972 	}
2973 
2974 	return (const usb_interface_descriptor_t *)usb_desc_iter_next(iter);
2975 }
2976 
2977 /* Returns the next non-interface descriptor, returning NULL when the
2978  * next descriptor would be an interface descriptor. */
2979 static const usb_descriptor_t *
2980 usb_desc_iter_next_non_interface(usbd_desc_iter_t *iter)
2981 {
2982 	const usb_descriptor_t *desc;
2983 
2984 	if ((desc = usb_desc_iter_peek_next(iter)) != NULL &&
2985 	    desc->bDescriptorType != UDESC_INTERFACE)
2986 	{
2987 		return usb_desc_iter_next(iter);
2988 	} else {
2989 		return NULL;
2990 	}
2991 }
2992 
2993 #ifdef UVIDEO_DEBUG
2994 static void
2995 usb_guid_print(const usb_guid_t *guid)
2996 {
2997 	printf("%04X-%02X-%02X-",
2998 	       UGETDW(guid->data1),
2999 	       UGETW(guid->data2),
3000 	       UGETW(guid->data3));
3001 	printf("%02X%02X-",
3002 	       guid->data4[0],
3003 	       guid->data4[1]);
3004 	printf("%02X%02X%02X%02X%02X%02X",
3005 	       guid->data4[2],
3006 	       guid->data4[3],
3007 	       guid->data4[4],
3008 	       guid->data4[5],
3009 	       guid->data4[6],
3010 	       guid->data4[7]);
3011 }
3012 #endif /* !UVIDEO_DEBUG */
3013 
3014 /* Returns less than zero, zero, or greater than zero if uguid is less
3015  * than, equal to, or greater than guid. */
3016 static int
3017 usb_guid_cmp(const usb_guid_t *uguid, const guid_t *guid)
3018 {
3019 	if (guid->data1 > UGETDW(uguid->data1))
3020 		return 1;
3021 	else if (guid->data1 < UGETDW(uguid->data1))
3022 		return -1;
3023 
3024 	if (guid->data2 > UGETW(uguid->data2))
3025 		return 1;
3026 	else if (guid->data2 < UGETW(uguid->data2))
3027 		return -1;
3028 
3029 	if (guid->data3 > UGETW(uguid->data3))
3030 		return 1;
3031 	else if (guid->data3 < UGETW(uguid->data3))
3032 		return -1;
3033 
3034 	return memcmp(guid->data4, uguid->data4, 8);
3035 }
3036