xref: /freebsd/sys/dev/sound/pcm/sound.c (revision 59c8e88e72633afbc47a4ace0d2170d00d51f7dc)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2005-2009 Ariff Abdullah <ariff@FreeBSD.org>
5  * Portions Copyright (c) Ryan Beasley <ryan.beasley@gmail.com> - GSoC 2006
6  * Copyright (c) 1999 Cameron Grant <cg@FreeBSD.org>
7  * Copyright (c) 1997 Luigi Rizzo
8  * All rights reserved.
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  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifdef HAVE_KERNEL_OPTION_HEADERS
33 #include "opt_snd.h"
34 #endif
35 
36 #include <dev/sound/pcm/sound.h>
37 #include <dev/sound/pcm/ac97.h>
38 #include <dev/sound/pcm/vchan.h>
39 #include <dev/sound/pcm/dsp.h>
40 #include <dev/sound/pcm/sndstat.h>
41 #include <dev/sound/version.h>
42 #include <sys/limits.h>
43 #include <sys/sysctl.h>
44 
45 #include "feeder_if.h"
46 
47 devclass_t pcm_devclass;
48 
49 int pcm_veto_load = 1;
50 
51 int snd_unit = -1;
52 
53 static int snd_unit_auto = -1;
54 SYSCTL_INT(_hw_snd, OID_AUTO, default_auto, CTLFLAG_RWTUN,
55     &snd_unit_auto, 0, "assign default unit to a newly attached device");
56 
57 int snd_maxautovchans = 16;
58 
59 SYSCTL_NODE(_hw, OID_AUTO, snd, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
60     "Sound driver");
61 
62 static void pcm_sysinit(device_t);
63 
64 /*
65  * XXX I've had enough with people not telling proper version/arch
66  *     while reporting problems, not after 387397913213th questions/requests.
67  */
68 static char snd_driver_version[] =
69     __XSTRING(SND_DRV_VERSION)"/"MACHINE_ARCH;
70 SYSCTL_STRING(_hw_snd, OID_AUTO, version, CTLFLAG_RD, &snd_driver_version,
71     0, "driver version/arch");
72 
73 /**
74  * @brief Unit number allocator for syncgroup IDs
75  */
76 struct unrhdr *pcmsg_unrhdr = NULL;
77 
78 static int
79 sndstat_prepare_pcm(SNDSTAT_PREPARE_PCM_ARGS)
80 {
81 	SNDSTAT_PREPARE_PCM_BEGIN();
82 	SNDSTAT_PREPARE_PCM_END();
83 }
84 
85 void *
86 snd_mtxcreate(const char *desc, const char *type)
87 {
88 	struct mtx *m;
89 
90 	m = malloc(sizeof(*m), M_DEVBUF, M_WAITOK | M_ZERO);
91 	mtx_init(m, desc, type, MTX_DEF);
92 	return m;
93 }
94 
95 void
96 snd_mtxfree(void *m)
97 {
98 	struct mtx *mtx = m;
99 
100 	mtx_destroy(mtx);
101 	free(mtx, M_DEVBUF);
102 }
103 
104 void
105 snd_mtxassert(void *m)
106 {
107 #ifdef INVARIANTS
108 	struct mtx *mtx = m;
109 
110 	mtx_assert(mtx, MA_OWNED);
111 #endif
112 }
113 
114 int
115 snd_setup_intr(device_t dev, struct resource *res, int flags, driver_intr_t hand, void *param, void **cookiep)
116 {
117 	struct snddev_info *d;
118 
119 	flags &= INTR_MPSAFE;
120 	flags |= INTR_TYPE_AV;
121 	d = device_get_softc(dev);
122 	if (d != NULL && (flags & INTR_MPSAFE))
123 		d->flags |= SD_F_MPSAFE;
124 
125 	return bus_setup_intr(dev, res, flags, NULL, hand, param, cookiep);
126 }
127 
128 static void
129 pcm_clonereset(struct snddev_info *d)
130 {
131 	int cmax;
132 
133 	PCM_BUSYASSERT(d);
134 
135 	cmax = d->playcount + d->reccount - 1;
136 	if (d->pvchancount > 0)
137 		cmax += max(d->pvchancount, snd_maxautovchans) - 1;
138 	if (d->rvchancount > 0)
139 		cmax += max(d->rvchancount, snd_maxautovchans) - 1;
140 	if (cmax > PCMMAXCLONE)
141 		cmax = PCMMAXCLONE;
142 	(void)snd_clone_gc(d->clones);
143 	(void)snd_clone_setmaxunit(d->clones, cmax);
144 }
145 
146 int
147 pcm_setvchans(struct snddev_info *d, int direction, int newcnt, int num)
148 {
149 	struct pcm_channel *c, *ch, *nch;
150 	struct pcmchan_caps *caps;
151 	int i, err, vcnt;
152 
153 	PCM_BUSYASSERT(d);
154 
155 	if ((direction == PCMDIR_PLAY && d->playcount < 1) ||
156 	    (direction == PCMDIR_REC && d->reccount < 1))
157 		return (ENODEV);
158 
159 	if (!(d->flags & SD_F_AUTOVCHAN))
160 		return (EINVAL);
161 
162 	if (newcnt < 0 || newcnt > SND_MAXVCHANS)
163 		return (E2BIG);
164 
165 	if (direction == PCMDIR_PLAY)
166 		vcnt = d->pvchancount;
167 	else if (direction == PCMDIR_REC)
168 		vcnt = d->rvchancount;
169 	else
170 		return (EINVAL);
171 
172 	if (newcnt > vcnt) {
173 		KASSERT(num == -1 ||
174 		    (num >= 0 && num < SND_MAXVCHANS && (newcnt - 1) == vcnt),
175 		    ("bogus vchan_create() request num=%d newcnt=%d vcnt=%d",
176 		    num, newcnt, vcnt));
177 		/* add new vchans - find a parent channel first */
178 		ch = NULL;
179 		CHN_FOREACH(c, d, channels.pcm) {
180 			CHN_LOCK(c);
181 			if (c->direction == direction &&
182 			    ((c->flags & CHN_F_HAS_VCHAN) || (vcnt == 0 &&
183 			    c->refcount < 1 &&
184 			    !(c->flags & (CHN_F_BUSY | CHN_F_VIRTUAL))))) {
185 				/*
186 				 * Reuse hw channel with vchans already
187 				 * created.
188 				 */
189 				if (c->flags & CHN_F_HAS_VCHAN) {
190 					ch = c;
191 					break;
192 				}
193 				/*
194 				 * No vchans ever created, look for
195 				 * channels with supported formats.
196 				 */
197 				caps = chn_getcaps(c);
198 				if (caps == NULL) {
199 					CHN_UNLOCK(c);
200 					continue;
201 				}
202 				for (i = 0; caps->fmtlist[i] != 0; i++) {
203 					if (caps->fmtlist[i] & AFMT_CONVERTIBLE)
204 						break;
205 				}
206 				if (caps->fmtlist[i] != 0) {
207 					ch = c;
208 				    	break;
209 				}
210 			}
211 			CHN_UNLOCK(c);
212 		}
213 		if (ch == NULL)
214 			return (EBUSY);
215 		ch->flags |= CHN_F_BUSY;
216 		err = 0;
217 		while (err == 0 && newcnt > vcnt) {
218 			err = vchan_create(ch, num);
219 			if (err == 0)
220 				vcnt++;
221 			else if (err == E2BIG && newcnt > vcnt)
222 				device_printf(d->dev,
223 				    "%s: err=%d Maximum channel reached.\n",
224 				    __func__, err);
225 		}
226 		if (vcnt == 0)
227 			ch->flags &= ~CHN_F_BUSY;
228 		CHN_UNLOCK(ch);
229 		if (err != 0)
230 			return (err);
231 		else
232 			pcm_clonereset(d);
233 	} else if (newcnt < vcnt) {
234 		KASSERT(num == -1,
235 		    ("bogus vchan_destroy() request num=%d", num));
236 		CHN_FOREACH(c, d, channels.pcm) {
237 			CHN_LOCK(c);
238 			if (c->direction != direction ||
239 			    CHN_EMPTY(c, children) ||
240 			    !(c->flags & CHN_F_HAS_VCHAN)) {
241 				CHN_UNLOCK(c);
242 				continue;
243 			}
244 			CHN_FOREACH_SAFE(ch, c, nch, children) {
245 				CHN_LOCK(ch);
246 				if (vcnt == 1 && c->refcount > 0) {
247 					CHN_UNLOCK(ch);
248 					break;
249 				}
250 				if (!(ch->flags & CHN_F_BUSY) &&
251 				    ch->refcount < 1) {
252 					err = vchan_destroy(ch);
253 					if (err == 0)
254 						vcnt--;
255 				} else
256 					CHN_UNLOCK(ch);
257 				if (vcnt == newcnt)
258 					break;
259 			}
260 			CHN_UNLOCK(c);
261 			break;
262 		}
263 		pcm_clonereset(d);
264 	}
265 
266 	return (0);
267 }
268 
269 /* return error status and a locked channel */
270 int
271 pcm_chnalloc(struct snddev_info *d, struct pcm_channel **ch, int direction,
272     pid_t pid, char *comm, int devunit)
273 {
274 	struct pcm_channel *c;
275 	int err, vchancount, vchan_num;
276 
277 	KASSERT(d != NULL && ch != NULL && (devunit == -1 ||
278 	    !(devunit & ~(SND_U_MASK | SND_D_MASK | SND_C_MASK))) &&
279 	    (direction == PCMDIR_PLAY || direction == PCMDIR_REC),
280 	    ("%s(): invalid d=%p ch=%p direction=%d pid=%d devunit=%d",
281 	    __func__, d, ch, direction, pid, devunit));
282 	PCM_BUSYASSERT(d);
283 
284 	/* Double check again. */
285 	if (devunit != -1) {
286 		switch (snd_unit2d(devunit)) {
287 		case SND_DEV_DSPHW_PLAY:
288 		case SND_DEV_DSPHW_VPLAY:
289 			if (direction != PCMDIR_PLAY)
290 				return (ENOTSUP);
291 			break;
292 		case SND_DEV_DSPHW_REC:
293 		case SND_DEV_DSPHW_VREC:
294 			if (direction != PCMDIR_REC)
295 				return (ENOTSUP);
296 			break;
297 		default:
298 			if (!(direction == PCMDIR_PLAY ||
299 			    direction == PCMDIR_REC))
300 				return (ENOTSUP);
301 			break;
302 		}
303 	}
304 
305 	*ch = NULL;
306 	vchan_num = 0;
307 	vchancount = (direction == PCMDIR_PLAY) ? d->pvchancount :
308 	    d->rvchancount;
309 
310 retry_chnalloc:
311 	err = ENOTSUP;
312 	/* scan for a free channel */
313 	CHN_FOREACH(c, d, channels.pcm) {
314 		CHN_LOCK(c);
315 		if (devunit == -1 && c->direction == direction &&
316 		    (c->flags & CHN_F_VIRTUAL)) {
317 			if (vchancount < snd_maxautovchans &&
318 			    vchan_num < CHN_CHAN(c)) {
319 			    	CHN_UNLOCK(c);
320 				goto vchan_alloc;
321 			}
322 			vchan_num++;
323 		}
324 		if (c->direction == direction && !(c->flags & CHN_F_BUSY) &&
325 		    (devunit == -1 || devunit == -2 || c->unit == devunit)) {
326 			c->flags |= CHN_F_BUSY;
327 			c->pid = pid;
328 			strlcpy(c->comm, (comm != NULL) ? comm :
329 			    CHN_COMM_UNKNOWN, sizeof(c->comm));
330 			*ch = c;
331 			return (0);
332 		} else if (c->unit == devunit) {
333 			if (c->direction != direction)
334 				err = ENOTSUP;
335 			else if (c->flags & CHN_F_BUSY)
336 				err = EBUSY;
337 			else
338 				err = EINVAL;
339 			CHN_UNLOCK(c);
340 			return (err);
341 		} else if ((devunit == -1 || devunit == -2) &&
342 		    c->direction == direction && (c->flags & CHN_F_BUSY))
343 			err = EBUSY;
344 		CHN_UNLOCK(c);
345 	}
346 
347 	if (devunit == -2)
348 		return (err);
349 
350 vchan_alloc:
351 	/* no channel available */
352 	if (devunit == -1 || snd_unit2d(devunit) == SND_DEV_DSPHW_VPLAY ||
353 	    snd_unit2d(devunit) == SND_DEV_DSPHW_VREC) {
354 		if (!(vchancount > 0 && vchancount < snd_maxautovchans) &&
355 		    (devunit == -1 || snd_unit2c(devunit) < snd_maxautovchans))
356 			return (err);
357 		err = pcm_setvchans(d, direction, vchancount + 1,
358 		    (devunit == -1) ? -1 : snd_unit2c(devunit));
359 		if (err == 0) {
360 			if (devunit == -1)
361 				devunit = -2;
362 			goto retry_chnalloc;
363 		}
364 	}
365 
366 	return (err);
367 }
368 
369 /* release a locked channel and unlock it */
370 int
371 pcm_chnrelease(struct pcm_channel *c)
372 {
373 	PCM_BUSYASSERT(c->parentsnddev);
374 	CHN_LOCKASSERT(c);
375 
376 	c->flags &= ~CHN_F_BUSY;
377 	c->pid = -1;
378 	strlcpy(c->comm, CHN_COMM_UNUSED, sizeof(c->comm));
379 	CHN_UNLOCK(c);
380 
381 	return (0);
382 }
383 
384 int
385 pcm_chnref(struct pcm_channel *c, int ref)
386 {
387 	PCM_BUSYASSERT(c->parentsnddev);
388 	CHN_LOCKASSERT(c);
389 
390 	c->refcount += ref;
391 
392 	return (c->refcount);
393 }
394 
395 static void
396 pcm_setmaxautovchans(struct snddev_info *d, int num)
397 {
398 	PCM_BUSYASSERT(d);
399 
400 	if (num < 0)
401 		return;
402 
403 	if (num >= 0 && d->pvchancount > num)
404 		(void)pcm_setvchans(d, PCMDIR_PLAY, num, -1);
405 	else if (num > 0 && d->pvchancount == 0)
406 		(void)pcm_setvchans(d, PCMDIR_PLAY, 1, -1);
407 
408 	if (num >= 0 && d->rvchancount > num)
409 		(void)pcm_setvchans(d, PCMDIR_REC, num, -1);
410 	else if (num > 0 && d->rvchancount == 0)
411 		(void)pcm_setvchans(d, PCMDIR_REC, 1, -1);
412 
413 	pcm_clonereset(d);
414 }
415 
416 static int
417 sysctl_hw_snd_default_unit(SYSCTL_HANDLER_ARGS)
418 {
419 	struct snddev_info *d;
420 	int error, unit;
421 
422 	unit = snd_unit;
423 	error = sysctl_handle_int(oidp, &unit, 0, req);
424 	if (error == 0 && req->newptr != NULL) {
425 		d = devclass_get_softc(pcm_devclass, unit);
426 		if (!PCM_REGISTERED(d) || CHN_EMPTY(d, channels.pcm))
427 			return EINVAL;
428 		snd_unit = unit;
429 		snd_unit_auto = 0;
430 	}
431 	return (error);
432 }
433 /* XXX: do we need a way to let the user change the default unit? */
434 SYSCTL_PROC(_hw_snd, OID_AUTO, default_unit,
435     CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_ANYBODY | CTLFLAG_NEEDGIANT, 0,
436     sizeof(int), sysctl_hw_snd_default_unit, "I",
437     "default sound device");
438 
439 static int
440 sysctl_hw_snd_maxautovchans(SYSCTL_HANDLER_ARGS)
441 {
442 	struct snddev_info *d;
443 	int i, v, error;
444 
445 	v = snd_maxautovchans;
446 	error = sysctl_handle_int(oidp, &v, 0, req);
447 	if (error == 0 && req->newptr != NULL) {
448 		if (v < 0)
449 			v = 0;
450 		if (v > SND_MAXVCHANS)
451 			v = SND_MAXVCHANS;
452 		snd_maxautovchans = v;
453 		for (i = 0; pcm_devclass != NULL &&
454 		    i < devclass_get_maxunit(pcm_devclass); i++) {
455 			d = devclass_get_softc(pcm_devclass, i);
456 			if (!PCM_REGISTERED(d))
457 				continue;
458 			PCM_ACQUIRE_QUICK(d);
459 			pcm_setmaxautovchans(d, v);
460 			PCM_RELEASE_QUICK(d);
461 		}
462 	}
463 	return (error);
464 }
465 SYSCTL_PROC(_hw_snd, OID_AUTO, maxautovchans,
466     CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_NEEDGIANT, 0, sizeof(int),
467     sysctl_hw_snd_maxautovchans, "I",
468     "maximum virtual channel");
469 
470 struct pcm_channel *
471 pcm_chn_create(struct snddev_info *d, struct pcm_channel *parent, kobj_class_t cls, int dir, int num, void *devinfo)
472 {
473 	struct pcm_channel *ch;
474 	int direction, err, rpnum, *pnum, max;
475 	int udc, device, chan;
476 	char *dirs, *devname, buf[CHN_NAMELEN];
477 
478 	PCM_BUSYASSERT(d);
479 	PCM_LOCKASSERT(d);
480 	KASSERT(num >= -1, ("invalid num=%d", num));
481 
482 	switch (dir) {
483 	case PCMDIR_PLAY:
484 		dirs = "play";
485 		direction = PCMDIR_PLAY;
486 		pnum = &d->playcount;
487 		device = SND_DEV_DSPHW_PLAY;
488 		max = SND_MAXHWCHAN;
489 		break;
490 	case PCMDIR_PLAY_VIRTUAL:
491 		dirs = "virtual";
492 		direction = PCMDIR_PLAY;
493 		pnum = &d->pvchancount;
494 		device = SND_DEV_DSPHW_VPLAY;
495 		max = SND_MAXVCHANS;
496 		break;
497 	case PCMDIR_REC:
498 		dirs = "record";
499 		direction = PCMDIR_REC;
500 		pnum = &d->reccount;
501 		device = SND_DEV_DSPHW_REC;
502 		max = SND_MAXHWCHAN;
503 		break;
504 	case PCMDIR_REC_VIRTUAL:
505 		dirs = "virtual";
506 		direction = PCMDIR_REC;
507 		pnum = &d->rvchancount;
508 		device = SND_DEV_DSPHW_VREC;
509 		max = SND_MAXVCHANS;
510 		break;
511 	default:
512 		return (NULL);
513 	}
514 
515 	chan = (num == -1) ? 0 : num;
516 
517 	if (*pnum >= max || chan >= max)
518 		return (NULL);
519 
520 	rpnum = 0;
521 
522 	CHN_FOREACH(ch, d, channels.pcm) {
523 		if (CHN_DEV(ch) != device)
524 			continue;
525 		if (chan == CHN_CHAN(ch)) {
526 			if (num != -1) {
527 				device_printf(d->dev,
528 				    "channel num=%d allocated!\n", chan);
529 				return (NULL);
530 			}
531 			chan++;
532 			if (chan >= max) {
533 				device_printf(d->dev,
534 				    "chan=%d > %d\n", chan, max);
535 				return (NULL);
536 			}
537 		}
538 		rpnum++;
539 	}
540 
541 	if (*pnum != rpnum) {
542 		device_printf(d->dev,
543 		    "%s(): WARNING: pnum screwed : dirs=%s pnum=%d rpnum=%d\n",
544 		    __func__, dirs, *pnum, rpnum);
545 		return (NULL);
546 	}
547 
548 	udc = snd_mkunit(device_get_unit(d->dev), device, chan);
549 	devname = dsp_unit2name(buf, sizeof(buf), udc);
550 
551 	if (devname == NULL) {
552 		device_printf(d->dev,
553 		    "Failed to query device name udc=0x%08x\n", udc);
554 		return (NULL);
555 	}
556 
557 	PCM_UNLOCK(d);
558 	ch = malloc(sizeof(*ch), M_DEVBUF, M_WAITOK | M_ZERO);
559 	ch->methods = kobj_create(cls, M_DEVBUF, M_WAITOK | M_ZERO);
560 	ch->unit = udc;
561 	ch->pid = -1;
562 	strlcpy(ch->comm, CHN_COMM_UNUSED, sizeof(ch->comm));
563 	ch->parentsnddev = d;
564 	ch->parentchannel = parent;
565 	ch->dev = d->dev;
566 	ch->trigger = PCMTRIG_STOP;
567 	snprintf(ch->name, sizeof(ch->name), "%s:%s:%s",
568 	    device_get_nameunit(ch->dev), dirs, devname);
569 
570 	err = chn_init(ch, devinfo, dir, direction);
571 	PCM_LOCK(d);
572 	if (err) {
573 		device_printf(d->dev, "chn_init(%s) failed: err = %d\n",
574 		    ch->name, err);
575 		kobj_delete(ch->methods, M_DEVBUF);
576 		free(ch, M_DEVBUF);
577 		return (NULL);
578 	}
579 
580 	return (ch);
581 }
582 
583 int
584 pcm_chn_destroy(struct pcm_channel *ch)
585 {
586 	struct snddev_info *d __diagused;
587 	int err;
588 
589 	d = ch->parentsnddev;
590 	PCM_BUSYASSERT(d);
591 
592 	err = chn_kill(ch);
593 	if (err) {
594 		device_printf(ch->dev, "chn_kill(%s) failed, err = %d\n",
595 		    ch->name, err);
596 		return (err);
597 	}
598 
599 	kobj_delete(ch->methods, M_DEVBUF);
600 	free(ch, M_DEVBUF);
601 
602 	return (0);
603 }
604 
605 int
606 pcm_chn_add(struct snddev_info *d, struct pcm_channel *ch)
607 {
608 	PCM_BUSYASSERT(d);
609 	PCM_LOCKASSERT(d);
610 	KASSERT(ch != NULL && (ch->direction == PCMDIR_PLAY ||
611 	    ch->direction == PCMDIR_REC), ("Invalid pcm channel"));
612 
613 	CHN_INSERT_SORT_ASCEND(d, ch, channels.pcm);
614 
615 	switch (CHN_DEV(ch)) {
616 	case SND_DEV_DSPHW_PLAY:
617 		d->playcount++;
618 		break;
619 	case SND_DEV_DSPHW_VPLAY:
620 		d->pvchancount++;
621 		break;
622 	case SND_DEV_DSPHW_REC:
623 		d->reccount++;
624 		break;
625 	case SND_DEV_DSPHW_VREC:
626 		d->rvchancount++;
627 		break;
628 	default:
629 		break;
630 	}
631 
632 	d->devcount++;
633 
634 	return (0);
635 }
636 
637 int
638 pcm_chn_remove(struct snddev_info *d, struct pcm_channel *ch)
639 {
640 	struct pcm_channel *tmp;
641 
642 	PCM_BUSYASSERT(d);
643 	PCM_LOCKASSERT(d);
644 
645 	tmp = NULL;
646 
647 	CHN_FOREACH(tmp, d, channels.pcm) {
648 		if (tmp == ch)
649 			break;
650 	}
651 
652 	if (tmp != ch)
653 		return (EINVAL);
654 
655 	CHN_REMOVE(d, ch, channels.pcm);
656 
657 	switch (CHN_DEV(ch)) {
658 	case SND_DEV_DSPHW_PLAY:
659 		d->playcount--;
660 		break;
661 	case SND_DEV_DSPHW_VPLAY:
662 		d->pvchancount--;
663 		break;
664 	case SND_DEV_DSPHW_REC:
665 		d->reccount--;
666 		break;
667 	case SND_DEV_DSPHW_VREC:
668 		d->rvchancount--;
669 		break;
670 	default:
671 		break;
672 	}
673 
674 	d->devcount--;
675 
676 	return (0);
677 }
678 
679 int
680 pcm_addchan(device_t dev, int dir, kobj_class_t cls, void *devinfo)
681 {
682 	struct snddev_info *d = device_get_softc(dev);
683 	struct pcm_channel *ch;
684 	int err;
685 
686 	PCM_BUSYASSERT(d);
687 
688 	PCM_LOCK(d);
689 	ch = pcm_chn_create(d, NULL, cls, dir, -1, devinfo);
690 	if (!ch) {
691 		device_printf(d->dev, "pcm_chn_create(%s, %d, %p) failed\n",
692 		    cls->name, dir, devinfo);
693 		PCM_UNLOCK(d);
694 		return (ENODEV);
695 	}
696 
697 	err = pcm_chn_add(d, ch);
698 	PCM_UNLOCK(d);
699 	if (err) {
700 		device_printf(d->dev, "pcm_chn_add(%s) failed, err=%d\n",
701 		    ch->name, err);
702 		pcm_chn_destroy(ch);
703 	}
704 
705 	return (err);
706 }
707 
708 static int
709 pcm_killchan(device_t dev)
710 {
711 	struct snddev_info *d = device_get_softc(dev);
712 	struct pcm_channel *ch;
713 	int error;
714 
715 	PCM_BUSYASSERT(d);
716 
717 	ch = CHN_FIRST(d, channels.pcm);
718 
719 	PCM_LOCK(d);
720 	error = pcm_chn_remove(d, ch);
721 	PCM_UNLOCK(d);
722 	if (error)
723 		return (error);
724 	return (pcm_chn_destroy(ch));
725 }
726 
727 static int
728 pcm_best_unit(int old)
729 {
730 	struct snddev_info *d;
731 	int i, best, bestprio, prio;
732 
733 	best = -1;
734 	bestprio = -100;
735 	for (i = 0; pcm_devclass != NULL &&
736 	    i < devclass_get_maxunit(pcm_devclass); i++) {
737 		d = devclass_get_softc(pcm_devclass, i);
738 		if (!PCM_REGISTERED(d))
739 			continue;
740 		prio = 0;
741 		if (d->playcount == 0)
742 			prio -= 10;
743 		if (d->reccount == 0)
744 			prio -= 2;
745 		if (prio > bestprio || (prio == bestprio && i == old)) {
746 			best = i;
747 			bestprio = prio;
748 		}
749 	}
750 	return (best);
751 }
752 
753 int
754 pcm_setstatus(device_t dev, char *str)
755 {
756 	struct snddev_info *d = device_get_softc(dev);
757 
758 	/* should only be called once */
759 	if (d->flags & SD_F_REGISTERED)
760 		return (EINVAL);
761 
762 	PCM_BUSYASSERT(d);
763 
764 	if (d->playcount == 0 || d->reccount == 0)
765 		d->flags |= SD_F_SIMPLEX;
766 
767 	if (d->playcount > 0 || d->reccount > 0)
768 		d->flags |= SD_F_AUTOVCHAN;
769 
770 	pcm_setmaxautovchans(d, snd_maxautovchans);
771 
772 	strlcpy(d->status, str, SND_STATUSLEN);
773 
774 	PCM_LOCK(d);
775 
776 	/* Last stage, enable cloning. */
777 	if (d->clones != NULL)
778 		(void)snd_clone_enable(d->clones);
779 
780 	/* Done, we're ready.. */
781 	d->flags |= SD_F_REGISTERED;
782 
783 	PCM_RELEASE(d);
784 
785 	PCM_UNLOCK(d);
786 
787 	/*
788 	 * Create all sysctls once SD_F_REGISTERED is set else
789 	 * tunable sysctls won't work:
790 	 */
791 	pcm_sysinit(dev);
792 
793 	if (snd_unit_auto < 0)
794 		snd_unit_auto = (snd_unit < 0) ? 1 : 0;
795 	if (snd_unit < 0 || snd_unit_auto > 1)
796 		snd_unit = device_get_unit(dev);
797 	else if (snd_unit_auto == 1)
798 		snd_unit = pcm_best_unit(snd_unit);
799 
800 	return (0);
801 }
802 
803 uint32_t
804 pcm_getflags(device_t dev)
805 {
806 	struct snddev_info *d = device_get_softc(dev);
807 
808 	return d->flags;
809 }
810 
811 void
812 pcm_setflags(device_t dev, uint32_t val)
813 {
814 	struct snddev_info *d = device_get_softc(dev);
815 
816 	d->flags = val;
817 }
818 
819 void *
820 pcm_getdevinfo(device_t dev)
821 {
822 	struct snddev_info *d = device_get_softc(dev);
823 
824 	return d->devinfo;
825 }
826 
827 unsigned int
828 pcm_getbuffersize(device_t dev, unsigned int minbufsz, unsigned int deflt, unsigned int maxbufsz)
829 {
830 	struct snddev_info *d = device_get_softc(dev);
831 	int sz, x;
832 
833 	sz = 0;
834 	if (resource_int_value(device_get_name(dev), device_get_unit(dev), "buffersize", &sz) == 0) {
835 		x = sz;
836 		RANGE(sz, minbufsz, maxbufsz);
837 		if (x != sz)
838 			device_printf(dev, "'buffersize=%d' hint is out of range (%d-%d), using %d\n", x, minbufsz, maxbufsz, sz);
839 		x = minbufsz;
840 		while (x < sz)
841 			x <<= 1;
842 		if (x > sz)
843 			x >>= 1;
844 		if (x != sz) {
845 			device_printf(dev, "'buffersize=%d' hint is not a power of 2, using %d\n", sz, x);
846 			sz = x;
847 		}
848 	} else {
849 		sz = deflt;
850 	}
851 
852 	d->bufsz = sz;
853 
854 	return sz;
855 }
856 
857 static int
858 sysctl_dev_pcm_bitperfect(SYSCTL_HANDLER_ARGS)
859 {
860 	struct snddev_info *d;
861 	int err, val;
862 
863 	d = oidp->oid_arg1;
864 	if (!PCM_REGISTERED(d))
865 		return (ENODEV);
866 
867 	PCM_LOCK(d);
868 	PCM_WAIT(d);
869 	val = (d->flags & SD_F_BITPERFECT) ? 1 : 0;
870 	PCM_ACQUIRE(d);
871 	PCM_UNLOCK(d);
872 
873 	err = sysctl_handle_int(oidp, &val, 0, req);
874 
875 	if (err == 0 && req->newptr != NULL) {
876 		if (!(val == 0 || val == 1)) {
877 			PCM_RELEASE_QUICK(d);
878 			return (EINVAL);
879 		}
880 
881 		PCM_LOCK(d);
882 
883 		d->flags &= ~SD_F_BITPERFECT;
884 		d->flags |= (val != 0) ? SD_F_BITPERFECT : 0;
885 
886 		PCM_RELEASE(d);
887 		PCM_UNLOCK(d);
888 	} else
889 		PCM_RELEASE_QUICK(d);
890 
891 	return (err);
892 }
893 
894 #ifdef SND_DEBUG
895 static int
896 sysctl_dev_pcm_clone_flags(SYSCTL_HANDLER_ARGS)
897 {
898 	struct snddev_info *d;
899 	uint32_t flags;
900 	int err;
901 
902 	d = oidp->oid_arg1;
903 	if (!PCM_REGISTERED(d) || d->clones == NULL)
904 		return (ENODEV);
905 
906 	PCM_ACQUIRE_QUICK(d);
907 
908 	flags = snd_clone_getflags(d->clones);
909 	err = sysctl_handle_int(oidp, &flags, 0, req);
910 
911 	if (err == 0 && req->newptr != NULL) {
912 		if (flags & ~SND_CLONE_MASK)
913 			err = EINVAL;
914 		else
915 			(void)snd_clone_setflags(d->clones, flags);
916 	}
917 
918 	PCM_RELEASE_QUICK(d);
919 
920 	return (err);
921 }
922 
923 static int
924 sysctl_dev_pcm_clone_deadline(SYSCTL_HANDLER_ARGS)
925 {
926 	struct snddev_info *d;
927 	int err, deadline;
928 
929 	d = oidp->oid_arg1;
930 	if (!PCM_REGISTERED(d) || d->clones == NULL)
931 		return (ENODEV);
932 
933 	PCM_ACQUIRE_QUICK(d);
934 
935 	deadline = snd_clone_getdeadline(d->clones);
936 	err = sysctl_handle_int(oidp, &deadline, 0, req);
937 
938 	if (err == 0 && req->newptr != NULL) {
939 		if (deadline < 0)
940 			err = EINVAL;
941 		else
942 			(void)snd_clone_setdeadline(d->clones, deadline);
943 	}
944 
945 	PCM_RELEASE_QUICK(d);
946 
947 	return (err);
948 }
949 
950 static int
951 sysctl_dev_pcm_clone_gc(SYSCTL_HANDLER_ARGS)
952 {
953 	struct snddev_info *d;
954 	int err, val;
955 
956 	d = oidp->oid_arg1;
957 	if (!PCM_REGISTERED(d) || d->clones == NULL)
958 		return (ENODEV);
959 
960 	val = 0;
961 	err = sysctl_handle_int(oidp, &val, 0, req);
962 
963 	if (err == 0 && req->newptr != NULL && val != 0) {
964 		PCM_ACQUIRE_QUICK(d);
965 		val = snd_clone_gc(d->clones);
966 		PCM_RELEASE_QUICK(d);
967 		if (bootverbose != 0 || snd_verbose > 3)
968 			device_printf(d->dev, "clone gc: pruned=%d\n", val);
969 	}
970 
971 	return (err);
972 }
973 
974 static int
975 sysctl_hw_snd_clone_gc(SYSCTL_HANDLER_ARGS)
976 {
977 	struct snddev_info *d;
978 	int i, err, val;
979 
980 	val = 0;
981 	err = sysctl_handle_int(oidp, &val, 0, req);
982 
983 	if (err == 0 && req->newptr != NULL && val != 0) {
984 		for (i = 0; pcm_devclass != NULL &&
985 		    i < devclass_get_maxunit(pcm_devclass); i++) {
986 			d = devclass_get_softc(pcm_devclass, i);
987 			if (!PCM_REGISTERED(d) || d->clones == NULL)
988 				continue;
989 			PCM_ACQUIRE_QUICK(d);
990 			val = snd_clone_gc(d->clones);
991 			PCM_RELEASE_QUICK(d);
992 			if (bootverbose != 0 || snd_verbose > 3)
993 				device_printf(d->dev, "clone gc: pruned=%d\n",
994 				    val);
995 		}
996 	}
997 
998 	return (err);
999 }
1000 SYSCTL_PROC(_hw_snd, OID_AUTO, clone_gc,
1001     CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_NEEDGIANT, 0, sizeof(int),
1002     sysctl_hw_snd_clone_gc, "I",
1003     "global clone garbage collector");
1004 #endif
1005 
1006 static u_int8_t
1007 pcm_mode_init(struct snddev_info *d)
1008 {
1009 	u_int8_t mode = 0;
1010 
1011 	if (d->playcount > 0)
1012 		mode |= PCM_MODE_PLAY;
1013 	if (d->reccount > 0)
1014 		mode |= PCM_MODE_REC;
1015 	if (d->mixer_dev != NULL)
1016 		mode |= PCM_MODE_MIXER;
1017 
1018 	return (mode);
1019 }
1020 
1021 static void
1022 pcm_sysinit(device_t dev)
1023 {
1024   	struct snddev_info *d = device_get_softc(dev);
1025 	u_int8_t mode;
1026 
1027 	mode = pcm_mode_init(d);
1028 
1029 	/* XXX: a user should be able to set this with a control tool, the
1030 	   sysadmin then needs min+max sysctls for this */
1031 	SYSCTL_ADD_UINT(device_get_sysctl_ctx(dev),
1032 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
1033             OID_AUTO, "buffersize", CTLFLAG_RD, &d->bufsz, 0, "allocated buffer size");
1034 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
1035 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
1036 	    "bitperfect", CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_MPSAFE, d,
1037 	    sizeof(d), sysctl_dev_pcm_bitperfect, "I",
1038 	    "bit-perfect playback/recording (0=disable, 1=enable)");
1039 	SYSCTL_ADD_UINT(device_get_sysctl_ctx(dev),
1040 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
1041 	    OID_AUTO, "mode", CTLFLAG_RD, NULL, mode,
1042 	    "mode (1=mixer, 2=play, 4=rec. The values are OR'ed if more than one"
1043 	    "mode is supported)");
1044 #ifdef SND_DEBUG
1045 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
1046 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
1047 	    "clone_flags", CTLTYPE_UINT | CTLFLAG_RWTUN | CTLFLAG_MPSAFE,
1048 	    d, sizeof(d), sysctl_dev_pcm_clone_flags, "IU",
1049 	    "clone flags");
1050 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
1051 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
1052 	    "clone_deadline", CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_MPSAFE,
1053 	    d, sizeof(d), sysctl_dev_pcm_clone_deadline, "I",
1054 	    "clone expiration deadline (ms)");
1055 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
1056 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
1057 	    "clone_gc",
1058 	    CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_MPSAFE, d, sizeof(d),
1059 	    sysctl_dev_pcm_clone_gc, "I", "clone garbage collector");
1060 #endif
1061 	if (d->flags & SD_F_AUTOVCHAN)
1062 		vchan_initsys(dev);
1063 	if (d->flags & SD_F_EQ)
1064 		feeder_eq_initsys(dev);
1065 }
1066 
1067 int
1068 pcm_register(device_t dev, void *devinfo, int numplay, int numrec)
1069 {
1070 	struct snddev_info *d;
1071 	int i;
1072 
1073 	if (pcm_veto_load) {
1074 		device_printf(dev, "disabled due to an error while initialising: %d\n", pcm_veto_load);
1075 
1076 		return EINVAL;
1077 	}
1078 
1079 	if (device_get_unit(dev) > PCMMAXUNIT) {
1080 		device_printf(dev, "PCMMAXUNIT reached : unit=%d > %d\n",
1081 		    device_get_unit(dev), PCMMAXUNIT);
1082 		device_printf(dev,
1083 		    "Use 'hw.snd.maxunit' tunable to raise the limit.\n");
1084 		return ENODEV;
1085 	}
1086 
1087 	d = device_get_softc(dev);
1088 	d->dev = dev;
1089 	d->lock = snd_mtxcreate(device_get_nameunit(dev), "sound cdev");
1090 	cv_init(&d->cv, device_get_nameunit(dev));
1091 	PCM_ACQUIRE_QUICK(d);
1092 	dsp_cdevinfo_init(d);
1093 #if 0
1094 	/*
1095 	 * d->flags should be cleared by the allocator of the softc.
1096 	 * We cannot clear this field here because several devices set
1097 	 * this flag before calling pcm_register().
1098 	 */
1099 	d->flags = 0;
1100 #endif
1101 	i = 0;
1102 	if (resource_int_value(device_get_name(dev), device_get_unit(dev),
1103 	    "vpc", &i) != 0 || i != 0)
1104 		d->flags |= SD_F_VPC;
1105 
1106 	if (resource_int_value(device_get_name(dev), device_get_unit(dev),
1107 	    "bitperfect", &i) == 0 && i != 0)
1108 		d->flags |= SD_F_BITPERFECT;
1109 
1110 	d->devinfo = devinfo;
1111 	d->devcount = 0;
1112 	d->reccount = 0;
1113 	d->playcount = 0;
1114 	d->pvchancount = 0;
1115 	d->rvchancount = 0;
1116 	d->pvchanrate = 0;
1117 	d->pvchanformat = 0;
1118 	d->rvchanrate = 0;
1119 	d->rvchanformat = 0;
1120 
1121 	/*
1122 	 * Create clone manager, disabled by default. Cloning will be
1123 	 * enabled during final stage of driver initialization through
1124 	 * pcm_setstatus().
1125 	 */
1126 	d->clones = snd_clone_create(SND_U_MASK | SND_D_MASK, PCMMAXCLONE,
1127 	    SND_CLONE_DEADLINE_DEFAULT, SND_CLONE_WAITOK |
1128 	    SND_CLONE_GC_ENABLE | SND_CLONE_GC_UNREF |
1129 	    SND_CLONE_GC_LASTREF | SND_CLONE_GC_EXPIRED);
1130 
1131 	CHN_INIT(d, channels.pcm);
1132 	CHN_INIT(d, channels.pcm.busy);
1133 	CHN_INIT(d, channels.pcm.opened);
1134 
1135 	/* XXX This is incorrect, but lets play along for now. */
1136 	if ((numplay == 0 || numrec == 0) && numplay != numrec)
1137 		d->flags |= SD_F_SIMPLEX;
1138 
1139 	sysctl_ctx_init(&d->play_sysctl_ctx);
1140 	d->play_sysctl_tree = SYSCTL_ADD_NODE(&d->play_sysctl_ctx,
1141 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO, "play",
1142 	    CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "playback channels node");
1143 	sysctl_ctx_init(&d->rec_sysctl_ctx);
1144 	d->rec_sysctl_tree = SYSCTL_ADD_NODE(&d->rec_sysctl_ctx,
1145 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO, "rec",
1146 	    CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "recording channels node");
1147 
1148 	if (numplay > 0 || numrec > 0)
1149 		d->flags |= SD_F_AUTOVCHAN;
1150 
1151 	sndstat_register(dev, d->status, sndstat_prepare_pcm);
1152 
1153 	return 0;
1154 }
1155 
1156 int
1157 pcm_unregister(device_t dev)
1158 {
1159 	struct snddev_info *d;
1160 	struct pcm_channel *ch;
1161 
1162 	d = device_get_softc(dev);
1163 
1164 	if (!PCM_ALIVE(d)) {
1165 		device_printf(dev, "unregister: device not configured\n");
1166 		return (0);
1167 	}
1168 
1169 	PCM_LOCK(d);
1170 	PCM_WAIT(d);
1171 
1172 	d->flags |= SD_F_DETACHING;
1173 
1174 	PCM_ACQUIRE(d);
1175 	PCM_UNLOCK(d);
1176 
1177 	CHN_FOREACH(ch, d, channels.pcm) {
1178 		CHN_LOCK(ch);
1179 		if (ch->refcount > 0) {
1180 			device_printf(dev,
1181 			    "unregister: channel %s busy (pid %d)\n",
1182 			    ch->name, ch->pid);
1183 			CHN_UNLOCK(ch);
1184 			PCM_RELEASE_QUICK(d);
1185 			return (EBUSY);
1186 		}
1187 		CHN_UNLOCK(ch);
1188 	}
1189 
1190 	if (d->clones != NULL) {
1191 		if (snd_clone_busy(d->clones) != 0) {
1192 			device_printf(dev, "unregister: clone busy\n");
1193 			PCM_RELEASE_QUICK(d);
1194 			return (EBUSY);
1195 		} else {
1196 			PCM_LOCK(d);
1197 			(void)snd_clone_disable(d->clones);
1198 			PCM_UNLOCK(d);
1199 		}
1200 	}
1201 
1202 	if (mixer_uninit(dev) == EBUSY) {
1203 		device_printf(dev, "unregister: mixer busy\n");
1204 		PCM_LOCK(d);
1205 		if (d->clones != NULL)
1206 			(void)snd_clone_enable(d->clones);
1207 		PCM_RELEASE(d);
1208 		PCM_UNLOCK(d);
1209 		return (EBUSY);
1210 	}
1211 
1212 	/* remove /dev/sndstat entry first */
1213 	sndstat_unregister(dev);
1214 
1215 	PCM_LOCK(d);
1216 	d->flags |= SD_F_DYING;
1217 	d->flags &= ~SD_F_REGISTERED;
1218 	PCM_UNLOCK(d);
1219 
1220 	/*
1221 	 * No lock being held, so this thing can be flushed without
1222 	 * stucking into devdrn oblivion.
1223 	 */
1224 	if (d->clones != NULL) {
1225 		snd_clone_destroy(d->clones);
1226 		d->clones = NULL;
1227 	}
1228 
1229 	if (d->play_sysctl_tree != NULL) {
1230 		sysctl_ctx_free(&d->play_sysctl_ctx);
1231 		d->play_sysctl_tree = NULL;
1232 	}
1233 	if (d->rec_sysctl_tree != NULL) {
1234 		sysctl_ctx_free(&d->rec_sysctl_ctx);
1235 		d->rec_sysctl_tree = NULL;
1236 	}
1237 
1238 	while (!CHN_EMPTY(d, channels.pcm))
1239 		pcm_killchan(dev);
1240 
1241 	dsp_cdevinfo_flush(d);
1242 
1243 	PCM_LOCK(d);
1244 	PCM_RELEASE(d);
1245 	cv_destroy(&d->cv);
1246 	PCM_UNLOCK(d);
1247 	snd_mtxfree(d->lock);
1248 
1249 	if (snd_unit == device_get_unit(dev)) {
1250 		snd_unit = pcm_best_unit(-1);
1251 		if (snd_unit_auto == 0)
1252 			snd_unit_auto = 1;
1253 	}
1254 
1255 	return (0);
1256 }
1257 
1258 /************************************************************************/
1259 
1260 /**
1261  * @brief	Handle OSSv4 SNDCTL_SYSINFO ioctl.
1262  *
1263  * @param si	Pointer to oss_sysinfo struct where information about the
1264  * 		sound subsystem will be written/copied.
1265  *
1266  * This routine returns information about the sound system, such as the
1267  * current OSS version, number of audio, MIDI, and mixer drivers, etc.
1268  * Also includes a bitmask showing which of the above types of devices
1269  * are open (busy).
1270  *
1271  * @note
1272  * Calling threads must not hold any snddev_info or pcm_channel locks.
1273  *
1274  * @author	Ryan Beasley <ryanb@FreeBSD.org>
1275  */
1276 void
1277 sound_oss_sysinfo(oss_sysinfo *si)
1278 {
1279 	static char si_product[] = "FreeBSD native OSS ABI";
1280 	static char si_version[] = __XSTRING(__FreeBSD_version);
1281 	static char si_license[] = "BSD";
1282 	static int intnbits = sizeof(int) * 8;	/* Better suited as macro?
1283 						   Must pester a C guru. */
1284 
1285 	struct snddev_info *d;
1286 	struct pcm_channel *c;
1287 	int i, j, ncards;
1288 
1289 	ncards = 0;
1290 
1291 	strlcpy(si->product, si_product, sizeof(si->product));
1292 	strlcpy(si->version, si_version, sizeof(si->version));
1293 	si->versionnum = SOUND_VERSION;
1294 	strlcpy(si->license, si_license, sizeof(si->license));
1295 
1296 	/*
1297 	 * Iterate over PCM devices and their channels, gathering up data
1298 	 * for the numaudios, ncards, and openedaudio fields.
1299 	 */
1300 	si->numaudios = 0;
1301 	bzero((void *)&si->openedaudio, sizeof(si->openedaudio));
1302 
1303 	j = 0;
1304 
1305 	for (i = 0; pcm_devclass != NULL &&
1306 	    i < devclass_get_maxunit(pcm_devclass); i++) {
1307 		d = devclass_get_softc(pcm_devclass, i);
1308 		if (!PCM_REGISTERED(d))
1309 			continue;
1310 
1311 		/* XXX Need Giant magic entry ??? */
1312 
1313 		/* See note in function's docblock */
1314 		PCM_UNLOCKASSERT(d);
1315 		PCM_LOCK(d);
1316 
1317 		si->numaudios += d->devcount;
1318 		++ncards;
1319 
1320 		CHN_FOREACH(c, d, channels.pcm) {
1321 			CHN_UNLOCKASSERT(c);
1322 			CHN_LOCK(c);
1323 			if (c->flags & CHN_F_BUSY)
1324 				si->openedaudio[j / intnbits] |=
1325 				    (1 << (j % intnbits));
1326 			CHN_UNLOCK(c);
1327 			j++;
1328 		}
1329 
1330 		PCM_UNLOCK(d);
1331 	}
1332 	si->numaudioengines = si->numaudios;
1333 
1334 	si->numsynths = 0;	/* OSSv4 docs:  this field is obsolete */
1335 	/**
1336 	 * @todo	Collect num{midis,timers}.
1337 	 *
1338 	 * Need access to sound/midi/midi.c::midistat_lock in order
1339 	 * to safely touch midi_devices and get a head count of, well,
1340 	 * MIDI devices.  midistat_lock is a global static (i.e., local to
1341 	 * midi.c), but midi_devices is a regular global; should the mutex
1342 	 * be publicized, or is there another way to get this information?
1343 	 *
1344 	 * NB:	MIDI/sequencer stuff is currently on hold.
1345 	 */
1346 	si->nummidis = 0;
1347 	si->numtimers = 0;
1348 	si->nummixers = mixer_count;
1349 	si->numcards = ncards;
1350 		/* OSSv4 docs:	Intended only for test apps; API doesn't
1351 		   really have much of a concept of cards.  Shouldn't be
1352 		   used by applications. */
1353 
1354 	/**
1355 	 * @todo	Fill in "busy devices" fields.
1356 	 *
1357 	 *  si->openedmidi = " MIDI devices
1358 	 */
1359 	bzero((void *)&si->openedmidi, sizeof(si->openedmidi));
1360 
1361 	/*
1362 	 * Si->filler is a reserved array, but according to docs each
1363 	 * element should be set to -1.
1364 	 */
1365 	for (i = 0; i < sizeof(si->filler)/sizeof(si->filler[0]); i++)
1366 		si->filler[i] = -1;
1367 }
1368 
1369 int
1370 sound_oss_card_info(oss_card_info *si)
1371 {
1372 	struct snddev_info *d;
1373 	int i, ncards;
1374 
1375 	ncards = 0;
1376 
1377 	for (i = 0; pcm_devclass != NULL &&
1378 	    i < devclass_get_maxunit(pcm_devclass); i++) {
1379 		d = devclass_get_softc(pcm_devclass, i);
1380 		if (!PCM_REGISTERED(d))
1381 			continue;
1382 
1383 		if (ncards++ != si->card)
1384 			continue;
1385 
1386 		PCM_UNLOCKASSERT(d);
1387 		PCM_LOCK(d);
1388 
1389 		strlcpy(si->shortname, device_get_nameunit(d->dev),
1390 		    sizeof(si->shortname));
1391 		strlcpy(si->longname, device_get_desc(d->dev),
1392 		    sizeof(si->longname));
1393 		strlcpy(si->hw_info, d->status, sizeof(si->hw_info));
1394 		si->intr_count = si->ack_count = 0;
1395 
1396 		PCM_UNLOCK(d);
1397 
1398 		return (0);
1399 	}
1400 	return (ENXIO);
1401 }
1402 
1403 /************************************************************************/
1404 
1405 static int
1406 sound_modevent(module_t mod, int type, void *data)
1407 {
1408 	int ret;
1409 
1410 	ret = 0;
1411 	switch (type) {
1412 		case MOD_LOAD:
1413 			pcm_devclass = devclass_create("pcm");
1414 			pcmsg_unrhdr = new_unrhdr(1, INT_MAX, NULL);
1415 			break;
1416 		case MOD_UNLOAD:
1417 			if (pcmsg_unrhdr != NULL) {
1418 				delete_unrhdr(pcmsg_unrhdr);
1419 				pcmsg_unrhdr = NULL;
1420 			}
1421 			break;
1422 		case MOD_SHUTDOWN:
1423 			break;
1424 		default:
1425 			ret = ENOTSUP;
1426 	}
1427 
1428 	return ret;
1429 }
1430 
1431 DEV_MODULE(sound, sound_modevent, NULL);
1432 MODULE_VERSION(sound, SOUND_MODVER);
1433