xref: /freebsd/sys/dev/sound/pcm/sound.c (revision b740c88bfb6453416926271c089262e7164dace3)
1 /*-
2  * Copyright (c) 2005-2009 Ariff Abdullah <ariff@FreeBSD.org>
3  * Portions Copyright (c) Ryan Beasley <ryan.beasley@gmail.com> - GSoC 2006
4  * Copyright (c) 1999 Cameron Grant <cg@FreeBSD.org>
5  * Copyright (c) 1997 Luigi Rizzo
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #ifdef HAVE_KERNEL_OPTION_HEADERS
31 #include "opt_snd.h"
32 #endif
33 
34 #include <dev/sound/pcm/sound.h>
35 #include <dev/sound/pcm/ac97.h>
36 #include <dev/sound/pcm/vchan.h>
37 #include <dev/sound/pcm/dsp.h>
38 #include <dev/sound/pcm/sndstat.h>
39 #include <dev/sound/version.h>
40 #include <sys/limits.h>
41 #include <sys/sysctl.h>
42 
43 #include "feeder_if.h"
44 
45 SND_DECLARE_FILE("$FreeBSD$");
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, 0, "Sound driver");
60 
61 static void pcm_sysinit(device_t);
62 
63 /*
64  * XXX I've had enough with people not telling proper version/arch
65  *     while reporting problems, not after 387397913213th questions/requests.
66  */
67 static char snd_driver_version[] =
68     __XSTRING(SND_DRV_VERSION)"/"MACHINE_ARCH;
69 SYSCTL_STRING(_hw_snd, OID_AUTO, version, CTLFLAG_RD, &snd_driver_version,
70     0, "driver version/arch");
71 
72 /**
73  * @brief Unit number allocator for syncgroup IDs
74  */
75 struct unrhdr *pcmsg_unrhdr = NULL;
76 
77 static int
78 sndstat_prepare_pcm(SNDSTAT_PREPARE_PCM_ARGS)
79 {
80 	SNDSTAT_PREPARE_PCM_BEGIN();
81 	SNDSTAT_PREPARE_PCM_END();
82 }
83 
84 void *
85 snd_mtxcreate(const char *desc, const char *type)
86 {
87 	struct mtx *m;
88 
89 	m = malloc(sizeof(*m), M_DEVBUF, M_WAITOK | M_ZERO);
90 	mtx_init(m, desc, type, MTX_DEF);
91 	return m;
92 }
93 
94 void
95 snd_mtxfree(void *m)
96 {
97 	struct mtx *mtx = m;
98 
99 	mtx_destroy(mtx);
100 	free(mtx, M_DEVBUF);
101 }
102 
103 void
104 snd_mtxassert(void *m)
105 {
106 #ifdef INVARIANTS
107 	struct mtx *mtx = m;
108 
109 	mtx_assert(mtx, MA_OWNED);
110 #endif
111 }
112 
113 int
114 snd_setup_intr(device_t dev, struct resource *res, int flags, driver_intr_t hand, void *param, void **cookiep)
115 {
116 	struct snddev_info *d;
117 
118 	flags &= INTR_MPSAFE;
119 	flags |= INTR_TYPE_AV;
120 	d = device_get_softc(dev);
121 	if (d != NULL && (flags & INTR_MPSAFE))
122 		d->flags |= SD_F_MPSAFE;
123 
124 	return bus_setup_intr(dev, res, flags, NULL, hand, param, cookiep);
125 }
126 
127 static void
128 pcm_clonereset(struct snddev_info *d)
129 {
130 	int cmax;
131 
132 	PCM_BUSYASSERT(d);
133 
134 	cmax = d->playcount + d->reccount - 1;
135 	if (d->pvchancount > 0)
136 		cmax += max(d->pvchancount, snd_maxautovchans) - 1;
137 	if (d->rvchancount > 0)
138 		cmax += max(d->rvchancount, snd_maxautovchans) - 1;
139 	if (cmax > PCMMAXCLONE)
140 		cmax = PCMMAXCLONE;
141 	(void)snd_clone_gc(d->clones);
142 	(void)snd_clone_setmaxunit(d->clones, cmax);
143 }
144 
145 int
146 pcm_setvchans(struct snddev_info *d, int direction, int newcnt, int num)
147 {
148 	struct pcm_channel *c, *ch, *nch;
149 	struct pcmchan_caps *caps;
150 	int i, err, vcnt;
151 
152 	PCM_BUSYASSERT(d);
153 
154 	if ((direction == PCMDIR_PLAY && d->playcount < 1) ||
155 	    (direction == PCMDIR_REC && d->reccount < 1))
156 		return (ENODEV);
157 
158 	if (!(d->flags & SD_F_AUTOVCHAN))
159 		return (EINVAL);
160 
161 	if (newcnt < 0 || newcnt > SND_MAXVCHANS)
162 		return (E2BIG);
163 
164 	if (direction == PCMDIR_PLAY)
165 		vcnt = d->pvchancount;
166 	else if (direction == PCMDIR_REC)
167 		vcnt = d->rvchancount;
168 	else
169 		return (EINVAL);
170 
171 	if (newcnt > vcnt) {
172 		KASSERT(num == -1 ||
173 		    (num >= 0 && num < SND_MAXVCHANS && (newcnt - 1) == vcnt),
174 		    ("bogus vchan_create() request num=%d newcnt=%d vcnt=%d",
175 		    num, newcnt, vcnt));
176 		/* add new vchans - find a parent channel first */
177 		ch = NULL;
178 		CHN_FOREACH(c, d, channels.pcm) {
179 			CHN_LOCK(c);
180 			if (c->direction == direction &&
181 			    ((c->flags & CHN_F_HAS_VCHAN) || (vcnt == 0 &&
182 			    c->refcount < 1 &&
183 			    !(c->flags & (CHN_F_BUSY | CHN_F_VIRTUAL))))) {
184 				/*
185 				 * Reuse hw channel with vchans already
186 				 * created.
187 				 */
188 				if (c->flags & CHN_F_HAS_VCHAN) {
189 					ch = c;
190 					break;
191 				}
192 				/*
193 				 * No vchans ever created, look for
194 				 * channels with supported formats.
195 				 */
196 				caps = chn_getcaps(c);
197 				if (caps == NULL) {
198 					CHN_UNLOCK(c);
199 					continue;
200 				}
201 				for (i = 0; caps->fmtlist[i] != 0; i++) {
202 					if (caps->fmtlist[i] & AFMT_CONVERTIBLE)
203 						break;
204 				}
205 				if (caps->fmtlist[i] != 0) {
206 					ch = c;
207 				    	break;
208 				}
209 			}
210 			CHN_UNLOCK(c);
211 		}
212 		if (ch == NULL)
213 			return (EBUSY);
214 		ch->flags |= CHN_F_BUSY;
215 		err = 0;
216 		while (err == 0 && newcnt > vcnt) {
217 			err = vchan_create(ch, num);
218 			if (err == 0)
219 				vcnt++;
220 			else if (err == E2BIG && newcnt > vcnt)
221 				device_printf(d->dev,
222 				    "%s: err=%d Maximum channel reached.\n",
223 				    __func__, err);
224 		}
225 		if (vcnt == 0)
226 			ch->flags &= ~CHN_F_BUSY;
227 		CHN_UNLOCK(ch);
228 		if (err != 0)
229 			return (err);
230 		else
231 			pcm_clonereset(d);
232 	} else if (newcnt < vcnt) {
233 		KASSERT(num == -1,
234 		    ("bogus vchan_destroy() request num=%d", num));
235 		CHN_FOREACH(c, d, channels.pcm) {
236 			CHN_LOCK(c);
237 			if (c->direction != direction ||
238 			    CHN_EMPTY(c, children) ||
239 			    !(c->flags & CHN_F_HAS_VCHAN)) {
240 				CHN_UNLOCK(c);
241 				continue;
242 			}
243 			CHN_FOREACH_SAFE(ch, c, nch, children) {
244 				CHN_LOCK(ch);
245 				if (vcnt == 1 && c->refcount > 0) {
246 					CHN_UNLOCK(ch);
247 					break;
248 				}
249 				if (!(ch->flags & CHN_F_BUSY) &&
250 				    ch->refcount < 1) {
251 					err = vchan_destroy(ch);
252 					if (err == 0)
253 						vcnt--;
254 				} else
255 					CHN_UNLOCK(ch);
256 				if (vcnt == newcnt)
257 					break;
258 			}
259 			CHN_UNLOCK(c);
260 			break;
261 		}
262 		pcm_clonereset(d);
263 	}
264 
265 	return (0);
266 }
267 
268 /* return error status and a locked channel */
269 int
270 pcm_chnalloc(struct snddev_info *d, struct pcm_channel **ch, int direction,
271     pid_t pid, char *comm, int devunit)
272 {
273 	struct pcm_channel *c;
274 	int err, vchancount, vchan_num;
275 
276 	KASSERT(d != NULL && ch != NULL && (devunit == -1 ||
277 	    !(devunit & ~(SND_U_MASK | SND_D_MASK | SND_C_MASK))) &&
278 	    (direction == PCMDIR_PLAY || direction == PCMDIR_REC),
279 	    ("%s(): invalid d=%p ch=%p direction=%d pid=%d devunit=%d",
280 	    __func__, d, ch, direction, pid, devunit));
281 	PCM_BUSYASSERT(d);
282 
283 	/* Double check again. */
284 	if (devunit != -1) {
285 		switch (snd_unit2d(devunit)) {
286 		case SND_DEV_DSPHW_PLAY:
287 		case SND_DEV_DSPHW_VPLAY:
288 			if (direction != PCMDIR_PLAY)
289 				return (ENOTSUP);
290 			break;
291 		case SND_DEV_DSPHW_REC:
292 		case SND_DEV_DSPHW_VREC:
293 			if (direction != PCMDIR_REC)
294 				return (ENOTSUP);
295 			break;
296 		default:
297 			if (!(direction == PCMDIR_PLAY ||
298 			    direction == PCMDIR_REC))
299 				return (ENOTSUP);
300 			break;
301 		}
302 	}
303 
304 	*ch = NULL;
305 	vchan_num = 0;
306 	vchancount = (direction == PCMDIR_PLAY) ? d->pvchancount :
307 	    d->rvchancount;
308 
309 retry_chnalloc:
310 	err = ENOTSUP;
311 	/* scan for a free channel */
312 	CHN_FOREACH(c, d, channels.pcm) {
313 		CHN_LOCK(c);
314 		if (devunit == -1 && c->direction == direction &&
315 		    (c->flags & CHN_F_VIRTUAL)) {
316 			if (vchancount < snd_maxautovchans &&
317 			    vchan_num < CHN_CHAN(c)) {
318 			    	CHN_UNLOCK(c);
319 				goto vchan_alloc;
320 			}
321 			vchan_num++;
322 		}
323 		if (c->direction == direction && !(c->flags & CHN_F_BUSY) &&
324 		    (devunit == -1 || devunit == -2 || c->unit == devunit)) {
325 			c->flags |= CHN_F_BUSY;
326 			c->pid = pid;
327 			strlcpy(c->comm, (comm != NULL) ? comm :
328 			    CHN_COMM_UNKNOWN, sizeof(c->comm));
329 			*ch = c;
330 			return (0);
331 		} else if (c->unit == devunit) {
332 			if (c->direction != direction)
333 				err = ENOTSUP;
334 			else if (c->flags & CHN_F_BUSY)
335 				err = EBUSY;
336 			else
337 				err = EINVAL;
338 			CHN_UNLOCK(c);
339 			return (err);
340 		} else if ((devunit == -1 || devunit == -2) &&
341 		    c->direction == direction && (c->flags & CHN_F_BUSY))
342 			err = EBUSY;
343 		CHN_UNLOCK(c);
344 	}
345 
346 	if (devunit == -2)
347 		return (err);
348 
349 vchan_alloc:
350 	/* no channel available */
351 	if (devunit == -1 || snd_unit2d(devunit) == SND_DEV_DSPHW_VPLAY ||
352 	    snd_unit2d(devunit) == SND_DEV_DSPHW_VREC) {
353 		if (!(vchancount > 0 && vchancount < snd_maxautovchans) &&
354 		    (devunit == -1 || snd_unit2c(devunit) < snd_maxautovchans))
355 			return (err);
356 		err = pcm_setvchans(d, direction, vchancount + 1,
357 		    (devunit == -1) ? -1 : snd_unit2c(devunit));
358 		if (err == 0) {
359 			if (devunit == -1)
360 				devunit = -2;
361 			goto retry_chnalloc;
362 		}
363 	}
364 
365 	return (err);
366 }
367 
368 /* release a locked channel and unlock it */
369 int
370 pcm_chnrelease(struct pcm_channel *c)
371 {
372 	PCM_BUSYASSERT(c->parentsnddev);
373 	CHN_LOCKASSERT(c);
374 
375 	c->flags &= ~CHN_F_BUSY;
376 	c->pid = -1;
377 	strlcpy(c->comm, CHN_COMM_UNUSED, sizeof(c->comm));
378 	CHN_UNLOCK(c);
379 
380 	return (0);
381 }
382 
383 int
384 pcm_chnref(struct pcm_channel *c, int ref)
385 {
386 	PCM_BUSYASSERT(c->parentsnddev);
387 	CHN_LOCKASSERT(c);
388 
389 	c->refcount += ref;
390 
391 	return (c->refcount);
392 }
393 
394 int
395 pcm_inprog(struct snddev_info *d, int delta)
396 {
397 	PCM_LOCKASSERT(d);
398 
399 	d->inprog += delta;
400 
401 	return (d->inprog);
402 }
403 
404 static void
405 pcm_setmaxautovchans(struct snddev_info *d, int num)
406 {
407 	PCM_BUSYASSERT(d);
408 
409 	if (num < 0)
410 		return;
411 
412 	if (num >= 0 && d->pvchancount > num)
413 		(void)pcm_setvchans(d, PCMDIR_PLAY, num, -1);
414 	else if (num > 0 && d->pvchancount == 0)
415 		(void)pcm_setvchans(d, PCMDIR_PLAY, 1, -1);
416 
417 	if (num >= 0 && d->rvchancount > num)
418 		(void)pcm_setvchans(d, PCMDIR_REC, num, -1);
419 	else if (num > 0 && d->rvchancount == 0)
420 		(void)pcm_setvchans(d, PCMDIR_REC, 1, -1);
421 
422 	pcm_clonereset(d);
423 }
424 
425 static int
426 sysctl_hw_snd_default_unit(SYSCTL_HANDLER_ARGS)
427 {
428 	struct snddev_info *d;
429 	int error, unit;
430 
431 	unit = snd_unit;
432 	error = sysctl_handle_int(oidp, &unit, 0, req);
433 	if (error == 0 && req->newptr != NULL) {
434 		d = devclass_get_softc(pcm_devclass, unit);
435 		if (!PCM_REGISTERED(d) || CHN_EMPTY(d, channels.pcm))
436 			return EINVAL;
437 		snd_unit = unit;
438 		snd_unit_auto = 0;
439 	}
440 	return (error);
441 }
442 /* XXX: do we need a way to let the user change the default unit? */
443 SYSCTL_PROC(_hw_snd, OID_AUTO, default_unit,
444 	    CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_ANYBODY,
445 	    0, sizeof(int), sysctl_hw_snd_default_unit, "I",
446 	    "default sound device");
447 
448 static int
449 sysctl_hw_snd_maxautovchans(SYSCTL_HANDLER_ARGS)
450 {
451 	struct snddev_info *d;
452 	int i, v, error;
453 
454 	v = snd_maxautovchans;
455 	error = sysctl_handle_int(oidp, &v, 0, req);
456 	if (error == 0 && req->newptr != NULL) {
457 		if (v < 0)
458 			v = 0;
459 		if (v > SND_MAXVCHANS)
460 			v = SND_MAXVCHANS;
461 		snd_maxautovchans = v;
462 		for (i = 0; pcm_devclass != NULL &&
463 		    i < devclass_get_maxunit(pcm_devclass); i++) {
464 			d = devclass_get_softc(pcm_devclass, i);
465 			if (!PCM_REGISTERED(d))
466 				continue;
467 			PCM_ACQUIRE_QUICK(d);
468 			pcm_setmaxautovchans(d, v);
469 			PCM_RELEASE_QUICK(d);
470 		}
471 	}
472 	return (error);
473 }
474 SYSCTL_PROC(_hw_snd, OID_AUTO, maxautovchans, CTLTYPE_INT | CTLFLAG_RWTUN,
475             0, sizeof(int), sysctl_hw_snd_maxautovchans, "I", "maximum virtual channel");
476 
477 struct pcm_channel *
478 pcm_chn_create(struct snddev_info *d, struct pcm_channel *parent, kobj_class_t cls, int dir, int num, void *devinfo)
479 {
480 	struct pcm_channel *ch;
481 	int direction, err, rpnum, *pnum, max;
482 	int udc, device, chan;
483 	char *dirs, *devname, buf[CHN_NAMELEN];
484 
485 	PCM_BUSYASSERT(d);
486 	PCM_LOCKASSERT(d);
487 	KASSERT(num >= -1, ("invalid num=%d", num));
488 
489 
490 	switch (dir) {
491 	case PCMDIR_PLAY:
492 		dirs = "play";
493 		direction = PCMDIR_PLAY;
494 		pnum = &d->playcount;
495 		device = SND_DEV_DSPHW_PLAY;
496 		max = SND_MAXHWCHAN;
497 		break;
498 	case PCMDIR_PLAY_VIRTUAL:
499 		dirs = "virtual";
500 		direction = PCMDIR_PLAY;
501 		pnum = &d->pvchancount;
502 		device = SND_DEV_DSPHW_VPLAY;
503 		max = SND_MAXVCHANS;
504 		break;
505 	case PCMDIR_REC:
506 		dirs = "record";
507 		direction = PCMDIR_REC;
508 		pnum = &d->reccount;
509 		device = SND_DEV_DSPHW_REC;
510 		max = SND_MAXHWCHAN;
511 		break;
512 	case PCMDIR_REC_VIRTUAL:
513 		dirs = "virtual";
514 		direction = PCMDIR_REC;
515 		pnum = &d->rvchancount;
516 		device = SND_DEV_DSPHW_VREC;
517 		max = SND_MAXVCHANS;
518 		break;
519 	default:
520 		return (NULL);
521 	}
522 
523 	chan = (num == -1) ? 0 : num;
524 
525 	if (*pnum >= max || chan >= max)
526 		return (NULL);
527 
528 	rpnum = 0;
529 
530 	CHN_FOREACH(ch, d, channels.pcm) {
531 		if (CHN_DEV(ch) != device)
532 			continue;
533 		if (chan == CHN_CHAN(ch)) {
534 			if (num != -1) {
535 				device_printf(d->dev,
536 				    "channel num=%d allocated!\n", chan);
537 				return (NULL);
538 			}
539 			chan++;
540 			if (chan >= max) {
541 				device_printf(d->dev,
542 				    "chan=%d > %d\n", chan, max);
543 				return (NULL);
544 			}
545 		}
546 		rpnum++;
547 	}
548 
549 	if (*pnum != rpnum) {
550 		device_printf(d->dev,
551 		    "%s(): WARNING: pnum screwed : dirs=%s pnum=%d rpnum=%d\n",
552 		    __func__, dirs, *pnum, rpnum);
553 		return (NULL);
554 	}
555 
556 	udc = snd_mkunit(device_get_unit(d->dev), device, chan);
557 	devname = dsp_unit2name(buf, sizeof(buf), udc);
558 
559 	if (devname == NULL) {
560 		device_printf(d->dev,
561 		    "Failed to query device name udc=0x%08x\n", udc);
562 		return (NULL);
563 	}
564 
565 	PCM_UNLOCK(d);
566 	ch = malloc(sizeof(*ch), M_DEVBUF, M_WAITOK | M_ZERO);
567 	ch->methods = kobj_create(cls, M_DEVBUF, M_WAITOK | M_ZERO);
568 	ch->unit = udc;
569 	ch->pid = -1;
570 	strlcpy(ch->comm, CHN_COMM_UNUSED, sizeof(ch->comm));
571 	ch->parentsnddev = d;
572 	ch->parentchannel = parent;
573 	ch->dev = d->dev;
574 	ch->trigger = PCMTRIG_STOP;
575 	snprintf(ch->name, sizeof(ch->name), "%s:%s:%s",
576 	    device_get_nameunit(ch->dev), dirs, devname);
577 
578 	err = chn_init(ch, devinfo, dir, direction);
579 	PCM_LOCK(d);
580 	if (err) {
581 		device_printf(d->dev, "chn_init(%s) failed: err = %d\n",
582 		    ch->name, err);
583 		kobj_delete(ch->methods, M_DEVBUF);
584 		free(ch, M_DEVBUF);
585 		return (NULL);
586 	}
587 
588 	return (ch);
589 }
590 
591 int
592 pcm_chn_destroy(struct pcm_channel *ch)
593 {
594 	struct snddev_info *d;
595 	int err;
596 
597 	d = ch->parentsnddev;
598 	PCM_BUSYASSERT(d);
599 
600 	err = chn_kill(ch);
601 	if (err) {
602 		device_printf(ch->dev, "chn_kill(%s) failed, err = %d\n",
603 		    ch->name, err);
604 		return (err);
605 	}
606 
607 	kobj_delete(ch->methods, M_DEVBUF);
608 	free(ch, M_DEVBUF);
609 
610 	return (0);
611 }
612 
613 int
614 pcm_chn_add(struct snddev_info *d, struct pcm_channel *ch)
615 {
616 	PCM_BUSYASSERT(d);
617 	PCM_LOCKASSERT(d);
618 	KASSERT(ch != NULL && (ch->direction == PCMDIR_PLAY ||
619 	    ch->direction == PCMDIR_REC), ("Invalid pcm channel"));
620 
621 	CHN_INSERT_SORT_ASCEND(d, ch, channels.pcm);
622 
623 	switch (CHN_DEV(ch)) {
624 	case SND_DEV_DSPHW_PLAY:
625 		d->playcount++;
626 		break;
627 	case SND_DEV_DSPHW_VPLAY:
628 		d->pvchancount++;
629 		break;
630 	case SND_DEV_DSPHW_REC:
631 		d->reccount++;
632 		break;
633 	case SND_DEV_DSPHW_VREC:
634 		d->rvchancount++;
635 		break;
636 	default:
637 		break;
638 	}
639 
640 	d->devcount++;
641 
642 	return (0);
643 }
644 
645 int
646 pcm_chn_remove(struct snddev_info *d, struct pcm_channel *ch)
647 {
648 	struct pcm_channel *tmp;
649 
650 	PCM_BUSYASSERT(d);
651 	PCM_LOCKASSERT(d);
652 
653 	tmp = NULL;
654 
655 	CHN_FOREACH(tmp, d, channels.pcm) {
656 		if (tmp == ch)
657 			break;
658 	}
659 
660 	if (tmp != ch)
661 		return (EINVAL);
662 
663 	CHN_REMOVE(d, ch, channels.pcm);
664 
665 	switch (CHN_DEV(ch)) {
666 	case SND_DEV_DSPHW_PLAY:
667 		d->playcount--;
668 		break;
669 	case SND_DEV_DSPHW_VPLAY:
670 		d->pvchancount--;
671 		break;
672 	case SND_DEV_DSPHW_REC:
673 		d->reccount--;
674 		break;
675 	case SND_DEV_DSPHW_VREC:
676 		d->rvchancount--;
677 		break;
678 	default:
679 		break;
680 	}
681 
682 	d->devcount--;
683 
684 	return (0);
685 }
686 
687 int
688 pcm_addchan(device_t dev, int dir, kobj_class_t cls, void *devinfo)
689 {
690 	struct snddev_info *d = device_get_softc(dev);
691 	struct pcm_channel *ch;
692 	int err;
693 
694 	PCM_BUSYASSERT(d);
695 
696 	PCM_LOCK(d);
697 	ch = pcm_chn_create(d, NULL, cls, dir, -1, devinfo);
698 	if (!ch) {
699 		device_printf(d->dev, "pcm_chn_create(%s, %d, %p) failed\n",
700 		    cls->name, dir, devinfo);
701 		PCM_UNLOCK(d);
702 		return (ENODEV);
703 	}
704 
705 	err = pcm_chn_add(d, ch);
706 	PCM_UNLOCK(d);
707 	if (err) {
708 		device_printf(d->dev, "pcm_chn_add(%s) failed, err=%d\n",
709 		    ch->name, err);
710 		pcm_chn_destroy(ch);
711 	}
712 
713 	return (err);
714 }
715 
716 static int
717 pcm_killchan(device_t dev)
718 {
719 	struct snddev_info *d = device_get_softc(dev);
720 	struct pcm_channel *ch;
721 	int error;
722 
723 	PCM_BUSYASSERT(d);
724 
725 	ch = CHN_FIRST(d, channels.pcm);
726 
727 	PCM_LOCK(d);
728 	error = pcm_chn_remove(d, ch);
729 	PCM_UNLOCK(d);
730 	if (error)
731 		return (error);
732 	return (pcm_chn_destroy(ch));
733 }
734 
735 static int
736 pcm_best_unit(int old)
737 {
738 	struct snddev_info *d;
739 	int i, best, bestprio, prio;
740 
741 	best = -1;
742 	bestprio = -100;
743 	for (i = 0; pcm_devclass != NULL &&
744 	    i < devclass_get_maxunit(pcm_devclass); i++) {
745 		d = devclass_get_softc(pcm_devclass, i);
746 		if (!PCM_REGISTERED(d))
747 			continue;
748 		prio = 0;
749 		if (d->playcount == 0)
750 			prio -= 10;
751 		if (d->reccount == 0)
752 			prio -= 2;
753 		if (prio > bestprio || (prio == bestprio && i == old)) {
754 			best = i;
755 			bestprio = prio;
756 		}
757 	}
758 	return (best);
759 }
760 
761 int
762 pcm_setstatus(device_t dev, char *str)
763 {
764 	struct snddev_info *d = device_get_softc(dev);
765 
766 	/* should only be called once */
767 	if (d->flags & SD_F_REGISTERED)
768 		return (EINVAL);
769 
770 	PCM_BUSYASSERT(d);
771 
772 	if (d->playcount == 0 || d->reccount == 0)
773 		d->flags |= SD_F_SIMPLEX;
774 
775 	if (d->playcount > 0 || d->reccount > 0)
776 		d->flags |= SD_F_AUTOVCHAN;
777 
778 	pcm_setmaxautovchans(d, snd_maxautovchans);
779 
780 	strlcpy(d->status, str, SND_STATUSLEN);
781 
782 	PCM_LOCK(d);
783 
784 	/* Last stage, enable cloning. */
785 	if (d->clones != NULL)
786 		(void)snd_clone_enable(d->clones);
787 
788 	/* Done, we're ready.. */
789 	d->flags |= SD_F_REGISTERED;
790 
791 	PCM_RELEASE(d);
792 
793 	PCM_UNLOCK(d);
794 
795 	/*
796 	 * Create all sysctls once SD_F_REGISTERED is set else
797 	 * tunable sysctls won't work:
798 	 */
799 	pcm_sysinit(dev);
800 
801 	if (snd_unit_auto < 0)
802 		snd_unit_auto = (snd_unit < 0) ? 1 : 0;
803 	if (snd_unit < 0 || snd_unit_auto > 1)
804 		snd_unit = device_get_unit(dev);
805 	else if (snd_unit_auto == 1)
806 		snd_unit = pcm_best_unit(snd_unit);
807 
808 	return (0);
809 }
810 
811 uint32_t
812 pcm_getflags(device_t dev)
813 {
814 	struct snddev_info *d = device_get_softc(dev);
815 
816 	return d->flags;
817 }
818 
819 void
820 pcm_setflags(device_t dev, uint32_t val)
821 {
822 	struct snddev_info *d = device_get_softc(dev);
823 
824 	d->flags = val;
825 }
826 
827 void *
828 pcm_getdevinfo(device_t dev)
829 {
830 	struct snddev_info *d = device_get_softc(dev);
831 
832 	return d->devinfo;
833 }
834 
835 unsigned int
836 pcm_getbuffersize(device_t dev, unsigned int minbufsz, unsigned int deflt, unsigned int maxbufsz)
837 {
838 	struct snddev_info *d = device_get_softc(dev);
839 	int sz, x;
840 
841 	sz = 0;
842 	if (resource_int_value(device_get_name(dev), device_get_unit(dev), "buffersize", &sz) == 0) {
843 		x = sz;
844 		RANGE(sz, minbufsz, maxbufsz);
845 		if (x != sz)
846 			device_printf(dev, "'buffersize=%d' hint is out of range (%d-%d), using %d\n", x, minbufsz, maxbufsz, sz);
847 		x = minbufsz;
848 		while (x < sz)
849 			x <<= 1;
850 		if (x > sz)
851 			x >>= 1;
852 		if (x != sz) {
853 			device_printf(dev, "'buffersize=%d' hint is not a power of 2, using %d\n", sz, x);
854 			sz = x;
855 		}
856 	} else {
857 		sz = deflt;
858 	}
859 
860 	d->bufsz = sz;
861 
862 	return sz;
863 }
864 
865 static int
866 sysctl_dev_pcm_bitperfect(SYSCTL_HANDLER_ARGS)
867 {
868 	struct snddev_info *d;
869 	int err, val;
870 
871 	d = oidp->oid_arg1;
872 	if (!PCM_REGISTERED(d))
873 		return (ENODEV);
874 
875 	PCM_LOCK(d);
876 	PCM_WAIT(d);
877 	val = (d->flags & SD_F_BITPERFECT) ? 1 : 0;
878 	PCM_ACQUIRE(d);
879 	PCM_UNLOCK(d);
880 
881 	err = sysctl_handle_int(oidp, &val, 0, req);
882 
883 	if (err == 0 && req->newptr != NULL) {
884 		if (!(val == 0 || val == 1)) {
885 			PCM_RELEASE_QUICK(d);
886 			return (EINVAL);
887 		}
888 
889 		PCM_LOCK(d);
890 
891 		d->flags &= ~SD_F_BITPERFECT;
892 		d->flags |= (val != 0) ? SD_F_BITPERFECT : 0;
893 
894 		PCM_RELEASE(d);
895 		PCM_UNLOCK(d);
896 	} else
897 		PCM_RELEASE_QUICK(d);
898 
899 	return (err);
900 }
901 
902 #ifdef SND_DEBUG
903 static int
904 sysctl_dev_pcm_clone_flags(SYSCTL_HANDLER_ARGS)
905 {
906 	struct snddev_info *d;
907 	uint32_t flags;
908 	int err;
909 
910 	d = oidp->oid_arg1;
911 	if (!PCM_REGISTERED(d) || d->clones == NULL)
912 		return (ENODEV);
913 
914 	PCM_ACQUIRE_QUICK(d);
915 
916 	flags = snd_clone_getflags(d->clones);
917 	err = sysctl_handle_int(oidp, &flags, 0, req);
918 
919 	if (err == 0 && req->newptr != NULL) {
920 		if (flags & ~SND_CLONE_MASK)
921 			err = EINVAL;
922 		else
923 			(void)snd_clone_setflags(d->clones, flags);
924 	}
925 
926 	PCM_RELEASE_QUICK(d);
927 
928 	return (err);
929 }
930 
931 static int
932 sysctl_dev_pcm_clone_deadline(SYSCTL_HANDLER_ARGS)
933 {
934 	struct snddev_info *d;
935 	int err, deadline;
936 
937 	d = oidp->oid_arg1;
938 	if (!PCM_REGISTERED(d) || d->clones == NULL)
939 		return (ENODEV);
940 
941 	PCM_ACQUIRE_QUICK(d);
942 
943 	deadline = snd_clone_getdeadline(d->clones);
944 	err = sysctl_handle_int(oidp, &deadline, 0, req);
945 
946 	if (err == 0 && req->newptr != NULL) {
947 		if (deadline < 0)
948 			err = EINVAL;
949 		else
950 			(void)snd_clone_setdeadline(d->clones, deadline);
951 	}
952 
953 	PCM_RELEASE_QUICK(d);
954 
955 	return (err);
956 }
957 
958 static int
959 sysctl_dev_pcm_clone_gc(SYSCTL_HANDLER_ARGS)
960 {
961 	struct snddev_info *d;
962 	int err, val;
963 
964 	d = oidp->oid_arg1;
965 	if (!PCM_REGISTERED(d) || d->clones == NULL)
966 		return (ENODEV);
967 
968 	val = 0;
969 	err = sysctl_handle_int(oidp, &val, 0, req);
970 
971 	if (err == 0 && req->newptr != NULL && val != 0) {
972 		PCM_ACQUIRE_QUICK(d);
973 		val = snd_clone_gc(d->clones);
974 		PCM_RELEASE_QUICK(d);
975 		if (bootverbose != 0 || snd_verbose > 3)
976 			device_printf(d->dev, "clone gc: pruned=%d\n", val);
977 	}
978 
979 	return (err);
980 }
981 
982 static int
983 sysctl_hw_snd_clone_gc(SYSCTL_HANDLER_ARGS)
984 {
985 	struct snddev_info *d;
986 	int i, err, val;
987 
988 	val = 0;
989 	err = sysctl_handle_int(oidp, &val, 0, req);
990 
991 	if (err == 0 && req->newptr != NULL && val != 0) {
992 		for (i = 0; pcm_devclass != NULL &&
993 		    i < devclass_get_maxunit(pcm_devclass); i++) {
994 			d = devclass_get_softc(pcm_devclass, i);
995 			if (!PCM_REGISTERED(d) || d->clones == NULL)
996 				continue;
997 			PCM_ACQUIRE_QUICK(d);
998 			val = snd_clone_gc(d->clones);
999 			PCM_RELEASE_QUICK(d);
1000 			if (bootverbose != 0 || snd_verbose > 3)
1001 				device_printf(d->dev, "clone gc: pruned=%d\n",
1002 				    val);
1003 		}
1004 	}
1005 
1006 	return (err);
1007 }
1008 SYSCTL_PROC(_hw_snd, OID_AUTO, clone_gc, CTLTYPE_INT | CTLFLAG_RWTUN,
1009     0, sizeof(int), sysctl_hw_snd_clone_gc, "I",
1010     "global clone garbage collector");
1011 #endif
1012 
1013 static void
1014 pcm_sysinit(device_t dev)
1015 {
1016   	struct snddev_info *d = device_get_softc(dev);
1017 
1018   	/* XXX: an user should be able to set this with a control tool, the
1019 	   sysadmin then needs min+max sysctls for this */
1020 	SYSCTL_ADD_UINT(device_get_sysctl_ctx(dev),
1021 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
1022             OID_AUTO, "buffersize", CTLFLAG_RD, &d->bufsz, 0, "allocated buffer size");
1023 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
1024 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
1025 	    "bitperfect", CTLTYPE_INT | CTLFLAG_RWTUN, d, sizeof(d),
1026 	    sysctl_dev_pcm_bitperfect, "I",
1027 	    "bit-perfect playback/recording (0=disable, 1=enable)");
1028 #ifdef SND_DEBUG
1029 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
1030 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
1031 	    "clone_flags", CTLTYPE_UINT | CTLFLAG_RWTUN, d, sizeof(d),
1032 	    sysctl_dev_pcm_clone_flags, "IU",
1033 	    "clone flags");
1034 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
1035 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
1036 	    "clone_deadline", CTLTYPE_INT | CTLFLAG_RWTUN, d, sizeof(d),
1037 	    sysctl_dev_pcm_clone_deadline, "I",
1038 	    "clone expiration deadline (ms)");
1039 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
1040 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
1041 	    "clone_gc", CTLTYPE_INT | CTLFLAG_RWTUN, d, sizeof(d),
1042 	    sysctl_dev_pcm_clone_gc, "I",
1043 	    "clone garbage collector");
1044 #endif
1045 	if (d->flags & SD_F_AUTOVCHAN)
1046 		vchan_initsys(dev);
1047 	if (d->flags & SD_F_EQ)
1048 		feeder_eq_initsys(dev);
1049 }
1050 
1051 int
1052 pcm_register(device_t dev, void *devinfo, int numplay, int numrec)
1053 {
1054 	struct snddev_info *d;
1055 	int i;
1056 
1057 	if (pcm_veto_load) {
1058 		device_printf(dev, "disabled due to an error while initialising: %d\n", pcm_veto_load);
1059 
1060 		return EINVAL;
1061 	}
1062 
1063 	if (device_get_unit(dev) > PCMMAXUNIT) {
1064 		device_printf(dev, "PCMMAXUNIT reached : unit=%d > %d\n",
1065 		    device_get_unit(dev), PCMMAXUNIT);
1066 		device_printf(dev,
1067 		    "Use 'hw.snd.maxunit' tunable to raise the limit.\n");
1068 		return ENODEV;
1069 	}
1070 
1071 	d = device_get_softc(dev);
1072 	d->dev = dev;
1073 	d->lock = snd_mtxcreate(device_get_nameunit(dev), "sound cdev");
1074 	cv_init(&d->cv, device_get_nameunit(dev));
1075 	PCM_ACQUIRE_QUICK(d);
1076 	dsp_cdevinfo_init(d);
1077 #if 0
1078 	/*
1079 	 * d->flags should be cleared by the allocator of the softc.
1080 	 * We cannot clear this field here because several devices set
1081 	 * this flag before calling pcm_register().
1082 	 */
1083 	d->flags = 0;
1084 #endif
1085 	i = 0;
1086 	if (resource_int_value(device_get_name(dev), device_get_unit(dev),
1087 	    "vpc", &i) != 0 || i != 0)
1088 		d->flags |= SD_F_VPC;
1089 
1090 	if (resource_int_value(device_get_name(dev), device_get_unit(dev),
1091 	    "bitperfect", &i) == 0 && i != 0)
1092 		d->flags |= SD_F_BITPERFECT;
1093 
1094 	d->devinfo = devinfo;
1095 	d->devcount = 0;
1096 	d->reccount = 0;
1097 	d->playcount = 0;
1098 	d->pvchancount = 0;
1099 	d->rvchancount = 0;
1100 	d->pvchanrate = 0;
1101 	d->pvchanformat = 0;
1102 	d->rvchanrate = 0;
1103 	d->rvchanformat = 0;
1104 	d->inprog = 0;
1105 
1106 	/*
1107 	 * Create clone manager, disabled by default. Cloning will be
1108 	 * enabled during final stage of driver initialization through
1109 	 * pcm_setstatus().
1110 	 */
1111 	d->clones = snd_clone_create(SND_U_MASK | SND_D_MASK, PCMMAXCLONE,
1112 	    SND_CLONE_DEADLINE_DEFAULT, SND_CLONE_WAITOK |
1113 	    SND_CLONE_GC_ENABLE | SND_CLONE_GC_UNREF |
1114 	    SND_CLONE_GC_LASTREF | SND_CLONE_GC_EXPIRED);
1115 
1116 	CHN_INIT(d, channels.pcm);
1117 	CHN_INIT(d, channels.pcm.busy);
1118 	CHN_INIT(d, channels.pcm.opened);
1119 
1120 	/* XXX This is incorrect, but lets play along for now. */
1121 	if ((numplay == 0 || numrec == 0) && numplay != numrec)
1122 		d->flags |= SD_F_SIMPLEX;
1123 
1124 	sysctl_ctx_init(&d->play_sysctl_ctx);
1125 	d->play_sysctl_tree = SYSCTL_ADD_NODE(&d->play_sysctl_ctx,
1126 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO, "play",
1127 	    CTLFLAG_RD, 0, "playback channels node");
1128 	sysctl_ctx_init(&d->rec_sysctl_ctx);
1129 	d->rec_sysctl_tree = SYSCTL_ADD_NODE(&d->rec_sysctl_ctx,
1130 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO, "rec",
1131 	    CTLFLAG_RD, 0, "record channels node");
1132 
1133 	if (numplay > 0 || numrec > 0)
1134 		d->flags |= SD_F_AUTOVCHAN;
1135 
1136 	sndstat_register(dev, d->status, sndstat_prepare_pcm);
1137 
1138 	return 0;
1139 }
1140 
1141 int
1142 pcm_unregister(device_t dev)
1143 {
1144 	struct snddev_info *d;
1145 	struct pcm_channel *ch;
1146 	struct thread *td;
1147 
1148 	td = curthread;
1149 	d = device_get_softc(dev);
1150 
1151 	if (!PCM_ALIVE(d)) {
1152 		device_printf(dev, "unregister: device not configured\n");
1153 		return (0);
1154 	}
1155 
1156 	if (sndstat_acquire(td) != 0) {
1157 		device_printf(dev, "unregister: sndstat busy\n");
1158 		return (EBUSY);
1159 	}
1160 
1161 	PCM_LOCK(d);
1162 	PCM_WAIT(d);
1163 
1164 	if (d->inprog != 0) {
1165 		device_printf(dev, "unregister: operation in progress\n");
1166 		PCM_UNLOCK(d);
1167 		sndstat_release(td);
1168 		return (EBUSY);
1169 	}
1170 
1171 	PCM_ACQUIRE(d);
1172 	PCM_UNLOCK(d);
1173 
1174 	CHN_FOREACH(ch, d, channels.pcm) {
1175 		CHN_LOCK(ch);
1176 		if (ch->refcount > 0) {
1177 			device_printf(dev,
1178 			    "unregister: channel %s busy (pid %d)\n",
1179 			    ch->name, ch->pid);
1180 			CHN_UNLOCK(ch);
1181 			PCM_RELEASE_QUICK(d);
1182 			sndstat_release(td);
1183 			return (EBUSY);
1184 		}
1185 		CHN_UNLOCK(ch);
1186 	}
1187 
1188 	if (d->clones != NULL) {
1189 		if (snd_clone_busy(d->clones) != 0) {
1190 			device_printf(dev, "unregister: clone busy\n");
1191 			PCM_RELEASE_QUICK(d);
1192 			sndstat_release(td);
1193 			return (EBUSY);
1194 		} else {
1195 			PCM_LOCK(d);
1196 			(void)snd_clone_disable(d->clones);
1197 			PCM_UNLOCK(d);
1198 		}
1199 	}
1200 
1201 	if (mixer_uninit(dev) == EBUSY) {
1202 		device_printf(dev, "unregister: mixer busy\n");
1203 		PCM_LOCK(d);
1204 		if (d->clones != NULL)
1205 			(void)snd_clone_enable(d->clones);
1206 		PCM_RELEASE(d);
1207 		PCM_UNLOCK(d);
1208 		sndstat_release(td);
1209 		return (EBUSY);
1210 	}
1211 
1212 	PCM_LOCK(d);
1213 	d->flags |= SD_F_DYING;
1214 	d->flags &= ~SD_F_REGISTERED;
1215 	PCM_UNLOCK(d);
1216 
1217 	/*
1218 	 * No lock being held, so this thing can be flushed without
1219 	 * stucking into devdrn oblivion.
1220 	 */
1221 	if (d->clones != NULL) {
1222 		snd_clone_destroy(d->clones);
1223 		d->clones = NULL;
1224 	}
1225 
1226 	if (d->play_sysctl_tree != NULL) {
1227 		sysctl_ctx_free(&d->play_sysctl_ctx);
1228 		d->play_sysctl_tree = NULL;
1229 	}
1230 	if (d->rec_sysctl_tree != NULL) {
1231 		sysctl_ctx_free(&d->rec_sysctl_ctx);
1232 		d->rec_sysctl_tree = NULL;
1233 	}
1234 
1235 	while (!CHN_EMPTY(d, channels.pcm))
1236 		pcm_killchan(dev);
1237 
1238 	dsp_cdevinfo_flush(d);
1239 
1240 	PCM_LOCK(d);
1241 	PCM_RELEASE(d);
1242 	cv_destroy(&d->cv);
1243 	PCM_UNLOCK(d);
1244 	snd_mtxfree(d->lock);
1245 	sndstat_unregister(dev);
1246 	sndstat_release(td);
1247 
1248 	if (snd_unit == device_get_unit(dev)) {
1249 		snd_unit = pcm_best_unit(-1);
1250 		if (snd_unit_auto == 0)
1251 			snd_unit_auto = 1;
1252 	}
1253 
1254 	return (0);
1255 }
1256 
1257 /************************************************************************/
1258 
1259 /**
1260  * @brief	Handle OSSv4 SNDCTL_SYSINFO ioctl.
1261  *
1262  * @param si	Pointer to oss_sysinfo struct where information about the
1263  * 		sound subsystem will be written/copied.
1264  *
1265  * This routine returns information about the sound system, such as the
1266  * current OSS version, number of audio, MIDI, and mixer drivers, etc.
1267  * Also includes a bitmask showing which of the above types of devices
1268  * are open (busy).
1269  *
1270  * @note
1271  * Calling threads must not hold any snddev_info or pcm_channel locks.
1272  *
1273  * @author	Ryan Beasley <ryanb@FreeBSD.org>
1274  */
1275 void
1276 sound_oss_sysinfo(oss_sysinfo *si)
1277 {
1278 	static char si_product[] = "FreeBSD native OSS ABI";
1279 	static char si_version[] = __XSTRING(__FreeBSD_version);
1280 	static char si_license[] = "BSD";
1281 	static int intnbits = sizeof(int) * 8;	/* Better suited as macro?
1282 						   Must pester a C guru. */
1283 
1284 	struct snddev_info *d;
1285 	struct pcm_channel *c;
1286 	int i, j, ncards;
1287 
1288 	ncards = 0;
1289 
1290 	strlcpy(si->product, si_product, sizeof(si->product));
1291 	strlcpy(si->version, si_version, sizeof(si->version));
1292 	si->versionnum = SOUND_VERSION;
1293 	strlcpy(si->license, si_license, sizeof(si->license));
1294 
1295 	/*
1296 	 * Iterate over PCM devices and their channels, gathering up data
1297 	 * for the numaudios, ncards, and openedaudio fields.
1298 	 */
1299 	si->numaudios = 0;
1300 	bzero((void *)&si->openedaudio, sizeof(si->openedaudio));
1301 
1302 	j = 0;
1303 
1304 	for (i = 0; pcm_devclass != NULL &&
1305 	    i < devclass_get_maxunit(pcm_devclass); i++) {
1306 		d = devclass_get_softc(pcm_devclass, i);
1307 		if (!PCM_REGISTERED(d))
1308 			continue;
1309 
1310 		/* XXX Need Giant magic entry ??? */
1311 
1312 		/* See note in function's docblock */
1313 		PCM_UNLOCKASSERT(d);
1314 		PCM_LOCK(d);
1315 
1316 		si->numaudios += d->devcount;
1317 		++ncards;
1318 
1319 		CHN_FOREACH(c, d, channels.pcm) {
1320 			CHN_UNLOCKASSERT(c);
1321 			CHN_LOCK(c);
1322 			if (c->flags & CHN_F_BUSY)
1323 				si->openedaudio[j / intnbits] |=
1324 				    (1 << (j % intnbits));
1325 			CHN_UNLOCK(c);
1326 			j++;
1327 		}
1328 
1329 		PCM_UNLOCK(d);
1330 	}
1331 	si->numaudioengines = si->numaudios;
1332 
1333 	si->numsynths = 0;	/* OSSv4 docs:  this field is obsolete */
1334 	/**
1335 	 * @todo	Collect num{midis,timers}.
1336 	 *
1337 	 * Need access to sound/midi/midi.c::midistat_lock in order
1338 	 * to safely touch midi_devices and get a head count of, well,
1339 	 * MIDI devices.  midistat_lock is a global static (i.e., local to
1340 	 * midi.c), but midi_devices is a regular global; should the mutex
1341 	 * be publicized, or is there another way to get this information?
1342 	 *
1343 	 * NB:	MIDI/sequencer stuff is currently on hold.
1344 	 */
1345 	si->nummidis = 0;
1346 	si->numtimers = 0;
1347 	si->nummixers = mixer_count;
1348 	si->numcards = ncards;
1349 		/* OSSv4 docs:	Intended only for test apps; API doesn't
1350 		   really have much of a concept of cards.  Shouldn't be
1351 		   used by applications. */
1352 
1353 	/**
1354 	 * @todo	Fill in "busy devices" fields.
1355 	 *
1356 	 *  si->openedmidi = " MIDI devices
1357 	 */
1358 	bzero((void *)&si->openedmidi, sizeof(si->openedmidi));
1359 
1360 	/*
1361 	 * Si->filler is a reserved array, but according to docs each
1362 	 * element should be set to -1.
1363 	 */
1364 	for (i = 0; i < sizeof(si->filler)/sizeof(si->filler[0]); i++)
1365 		si->filler[i] = -1;
1366 }
1367 
1368 int
1369 sound_oss_card_info(oss_card_info *si)
1370 {
1371 	struct snddev_info *d;
1372 	int i, ncards;
1373 
1374 	ncards = 0;
1375 
1376 	for (i = 0; pcm_devclass != NULL &&
1377 	    i < devclass_get_maxunit(pcm_devclass); i++) {
1378 		d = devclass_get_softc(pcm_devclass, i);
1379 		if (!PCM_REGISTERED(d))
1380 			continue;
1381 
1382 		if (ncards++ != si->card)
1383 			continue;
1384 
1385 		PCM_UNLOCKASSERT(d);
1386 		PCM_LOCK(d);
1387 
1388 		strlcpy(si->shortname, device_get_nameunit(d->dev),
1389 		    sizeof(si->shortname));
1390 		strlcpy(si->longname, device_get_desc(d->dev),
1391 		    sizeof(si->longname));
1392 		strlcpy(si->hw_info, d->status, sizeof(si->hw_info));
1393 		si->intr_count = si->ack_count = 0;
1394 
1395 		PCM_UNLOCK(d);
1396 
1397 		return (0);
1398 	}
1399 	return (ENXIO);
1400 }
1401 
1402 /************************************************************************/
1403 
1404 static int
1405 sound_modevent(module_t mod, int type, void *data)
1406 {
1407 	int ret;
1408 #if 0
1409 	return (midi_modevent(mod, type, data));
1410 #else
1411 	ret = 0;
1412 
1413 	switch(type) {
1414 		case MOD_LOAD:
1415 			pcmsg_unrhdr = new_unrhdr(1, INT_MAX, NULL);
1416 			break;
1417 		case MOD_UNLOAD:
1418 			ret = sndstat_acquire(curthread);
1419 			if (ret != 0)
1420 				break;
1421 			if (pcmsg_unrhdr != NULL) {
1422 				delete_unrhdr(pcmsg_unrhdr);
1423 				pcmsg_unrhdr = NULL;
1424 			}
1425 			break;
1426 		case MOD_SHUTDOWN:
1427 			break;
1428 		default:
1429 			ret = ENOTSUP;
1430 	}
1431 
1432 	return ret;
1433 #endif
1434 }
1435 
1436 DEV_MODULE(sound, sound_modevent, NULL);
1437 MODULE_VERSION(sound, SOUND_MODVER);
1438