xref: /freebsd/sys/dev/sound/pcm/sound.c (revision f9218d3d4fd34f082473b3a021c6d4d109fb47cf)
1 /*
2  * Copyright (c) 1999 Cameron Grant <gandalf@vilnya.demon.co.uk>
3  * (C) 1997 Luigi Rizzo (luigi@iet.unipi.it)
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <dev/sound/pcm/sound.h>
29 #include <dev/sound/pcm/vchan.h>
30 #include <sys/sysctl.h>
31 
32 #include "feeder_if.h"
33 
34 SND_DECLARE_FILE("$FreeBSD$");
35 
36 struct snddev_channel {
37 	SLIST_ENTRY(snddev_channel) link;
38 	struct pcm_channel *channel;
39 };
40 
41 struct snddev_info {
42 	SLIST_HEAD(, snddev_channel) channels;
43 	struct pcm_channel *fakechan;
44 	unsigned devcount, playcount, reccount, vchancount;
45 	unsigned flags;
46 	int inprog;
47 	unsigned int bufsz;
48 	void *devinfo;
49 	device_t dev;
50 	char status[SND_STATUSLEN];
51 	struct sysctl_ctx_list sysctl_tree;
52 	struct sysctl_oid *sysctl_tree_top;
53 	struct mtx *lock;
54 };
55 
56 devclass_t pcm_devclass;
57 
58 int pcm_veto_load = 1;
59 
60 #ifdef USING_DEVFS
61 int snd_unit = 0;
62 TUNABLE_INT("hw.snd.unit", &snd_unit);
63 #endif
64 
65 int snd_maxautovchans = 0;
66 TUNABLE_INT("hw.snd.maxautovchans", &snd_maxautovchans);
67 
68 SYSCTL_NODE(_hw, OID_AUTO, snd, CTLFLAG_RD, 0, "Sound driver");
69 
70 static int sndstat_prepare_pcm(struct sbuf *s, device_t dev, int verbose);
71 
72 struct sysctl_ctx_list *
73 snd_sysctl_tree(device_t dev)
74 {
75     	struct snddev_info *d = device_get_softc(dev);
76 
77 	return &d->sysctl_tree;
78 }
79 
80 struct sysctl_oid *
81 snd_sysctl_tree_top(device_t dev)
82 {
83     	struct snddev_info *d = device_get_softc(dev);
84 
85 	return d->sysctl_tree_top;
86 }
87 
88 void *
89 snd_mtxcreate(const char *desc, const char *type)
90 {
91 #ifdef USING_MUTEX
92 	struct mtx *m;
93 
94 	m = malloc(sizeof(*m), M_DEVBUF, M_WAITOK | M_ZERO);
95 	if (m == NULL)
96 		return NULL;
97 	mtx_init(m, desc, type, MTX_RECURSE);
98 	return m;
99 #else
100 	return (void *)0xcafebabe;
101 #endif
102 }
103 
104 void
105 snd_mtxfree(void *m)
106 {
107 #ifdef USING_MUTEX
108 	struct mtx *mtx = m;
109 
110 	/* mtx_assert(mtx, MA_OWNED); */
111 	mtx_destroy(mtx);
112 	free(mtx, M_DEVBUF);
113 #endif
114 }
115 
116 void
117 snd_mtxassert(void *m)
118 {
119 #ifdef USING_MUTEX
120 #ifdef INVARIANTS
121 	struct mtx *mtx = m;
122 
123 	mtx_assert(mtx, MA_OWNED);
124 #endif
125 #endif
126 }
127 /*
128 void
129 snd_mtxlock(void *m)
130 {
131 #ifdef USING_MUTEX
132 	struct mtx *mtx = m;
133 
134 	mtx_lock(mtx);
135 #endif
136 }
137 
138 void
139 snd_mtxunlock(void *m)
140 {
141 #ifdef USING_MUTEX
142 	struct mtx *mtx = m;
143 
144 	mtx_unlock(mtx);
145 #endif
146 }
147 */
148 int
149 snd_setup_intr(device_t dev, struct resource *res, int flags, driver_intr_t hand, void *param, void **cookiep)
150 {
151 #ifdef USING_MUTEX
152 	flags &= INTR_MPSAFE;
153 	flags |= INTR_TYPE_AV;
154 #else
155 	flags = INTR_TYPE_AV;
156 #endif
157 	return bus_setup_intr(dev, res, flags, hand, param, cookiep);
158 }
159 
160 void
161 pcm_lock(struct snddev_info *d)
162 {
163 	snd_mtxlock(d->lock);
164 }
165 
166 void
167 pcm_unlock(struct snddev_info *d)
168 {
169 	snd_mtxunlock(d->lock);
170 }
171 
172 struct pcm_channel *
173 pcm_getfakechan(struct snddev_info *d)
174 {
175 	return d->fakechan;
176 }
177 
178 /* return a locked channel */
179 struct pcm_channel *
180 pcm_chnalloc(struct snddev_info *d, int direction, pid_t pid, int chnum)
181 {
182 	struct pcm_channel *c;
183     	struct snddev_channel *sce;
184 	int err;
185 
186 	snd_mtxassert(d->lock);
187 
188 	/* scan for a free channel */
189 	SLIST_FOREACH(sce, &d->channels, link) {
190 		c = sce->channel;
191 		CHN_LOCK(c);
192 		if ((c->direction == direction) && !(c->flags & CHN_F_BUSY)) {
193 			if (chnum == -1 || c->num == chnum) {
194 				c->flags |= CHN_F_BUSY;
195 				c->pid = pid;
196 				return c;
197 			}
198 		}
199 		CHN_UNLOCK(c);
200 	}
201 
202 	/* no channel available */
203 	if (direction == PCMDIR_PLAY) {
204 		if ((d->vchancount > 0) && (d->vchancount < snd_maxautovchans)) {
205 			/* try to create a vchan */
206 			SLIST_FOREACH(sce, &d->channels, link) {
207 				c = sce->channel;
208 				if (!SLIST_EMPTY(&c->children)) {
209 					err = vchan_create(c);
210 					if (!err)
211 						return pcm_chnalloc(d, direction, pid, -1);
212 					else
213 						device_printf(d->dev, "vchan_create(%s) == %d\n", c->name, err);
214 				}
215 			}
216 		}
217 	}
218 
219 	return NULL;
220 }
221 
222 /* release a locked channel and unlock it */
223 int
224 pcm_chnrelease(struct pcm_channel *c)
225 {
226 	CHN_LOCKASSERT(c);
227 	c->flags &= ~CHN_F_BUSY;
228 	c->pid = -1;
229 	CHN_UNLOCK(c);
230 	return 0;
231 }
232 
233 int
234 pcm_chnref(struct pcm_channel *c, int ref)
235 {
236 	int r;
237 
238 	CHN_LOCKASSERT(c);
239 	c->refcount += ref;
240 	r = c->refcount;
241 	return r;
242 }
243 
244 int
245 pcm_inprog(struct snddev_info *d, int delta)
246 {
247 	d->inprog += delta;
248 	return d->inprog;
249 }
250 
251 static void
252 pcm_setmaxautovchans(struct snddev_info *d, int num)
253 {
254 	struct pcm_channel *c;
255     	struct snddev_channel *sce;
256 	int err, done;
257 
258 	if (num > 0 && d->vchancount == 0) {
259 		SLIST_FOREACH(sce, &d->channels, link) {
260 			c = sce->channel;
261 			if ((c->direction == PCMDIR_PLAY) && !(c->flags & CHN_F_BUSY)) {
262 				c->flags |= CHN_F_BUSY;
263 				err = vchan_create(c);
264 				if (err) {
265 					device_printf(d->dev, "vchan_create(%s) == %d\n", c->name, err);
266 					c->flags &= ~CHN_F_BUSY;
267 				}
268 				return;
269 			}
270 		}
271 	}
272 	if (num == 0 && d->vchancount > 0) {
273 		done = 0;
274 		while (!done) {
275 			done = 1;
276 			SLIST_FOREACH(sce, &d->channels, link) {
277 				c = sce->channel;
278 				if ((c->flags & CHN_F_VIRTUAL) && !(c->flags & CHN_F_BUSY)) {
279 					done = 0;
280 					err = vchan_destroy(c);
281 					if (err)
282 						device_printf(d->dev, "vchan_destroy(%s) == %d\n", c->name, err);
283 					break;		/* restart */
284 				}
285 			}
286 		}
287 	}
288 }
289 
290 #ifdef USING_DEVFS
291 static int
292 sysctl_hw_snd_unit(SYSCTL_HANDLER_ARGS)
293 {
294 	struct snddev_info *d;
295 	int error, unit;
296 
297 	unit = snd_unit;
298 	error = sysctl_handle_int(oidp, &unit, sizeof(unit), req);
299 	if (error == 0 && req->newptr != NULL) {
300 		if (unit < 0 || unit >= devclass_get_maxunit(pcm_devclass))
301 			return EINVAL;
302 		d = devclass_get_softc(pcm_devclass, unit);
303 		if (d == NULL || SLIST_EMPTY(&d->channels))
304 			return EINVAL;
305 		snd_unit = unit;
306 	}
307 	return (error);
308 }
309 SYSCTL_PROC(_hw_snd, OID_AUTO, unit, CTLTYPE_INT | CTLFLAG_RW,
310             0, sizeof(int), sysctl_hw_snd_unit, "I", "");
311 #endif
312 
313 static int
314 sysctl_hw_snd_maxautovchans(SYSCTL_HANDLER_ARGS)
315 {
316 	struct snddev_info *d;
317 	int i, v, error;
318 
319 	v = snd_maxautovchans;
320 	error = sysctl_handle_int(oidp, &v, sizeof(v), req);
321 	if (error == 0 && req->newptr != NULL) {
322 		if (v < 0 || v >= SND_MAXVCHANS)
323 			return EINVAL;
324 		if (v != snd_maxautovchans) {
325 			for (i = 0; i < devclass_get_maxunit(pcm_devclass); i++) {
326 				d = devclass_get_softc(pcm_devclass, i);
327 				if (!d)
328 					continue;
329 				pcm_setmaxautovchans(d, v);
330 			}
331 		}
332 		snd_maxautovchans = v;
333 	}
334 	return (error);
335 }
336 SYSCTL_PROC(_hw_snd, OID_AUTO, maxautovchans, CTLTYPE_INT | CTLFLAG_RW,
337             0, sizeof(int), sysctl_hw_snd_maxautovchans, "I", "");
338 
339 struct pcm_channel *
340 pcm_chn_create(struct snddev_info *d, struct pcm_channel *parent, kobj_class_t cls, int dir, void *devinfo)
341 {
342 	struct pcm_channel *ch;
343 	char *dirs;
344     	int err, *pnum;
345 
346 	switch(dir) {
347 	case PCMDIR_PLAY:
348 		dirs = "play";
349 		pnum = &d->playcount;
350 		break;
351 
352 	case PCMDIR_REC:
353 		dirs = "record";
354 		pnum = &d->reccount;
355 		break;
356 
357 	case PCMDIR_VIRTUAL:
358 		dirs = "virtual";
359 		dir = PCMDIR_PLAY;
360 		pnum = &d->vchancount;
361 		break;
362 
363 	default:
364 		return NULL;
365 	}
366 
367 	ch = malloc(sizeof(*ch), M_DEVBUF, M_WAITOK | M_ZERO);
368 	if (!ch)
369 		return NULL;
370 
371 	ch->methods = kobj_create(cls, M_DEVBUF, M_WAITOK);
372 	if (!ch->methods) {
373 		free(ch, M_DEVBUF);
374 
375 		return NULL;
376 	}
377 
378 	snd_mtxlock(d->lock);
379 	ch->num = (*pnum)++;
380 	snd_mtxunlock(d->lock);
381 
382 	ch->pid = -1;
383 	ch->parentsnddev = d;
384 	ch->parentchannel = parent;
385 	ch->dev = d->dev;
386 	snprintf(ch->name, 32, "%s:%s:%d", device_get_nameunit(ch->dev), dirs, ch->num);
387 
388 	err = chn_init(ch, devinfo, dir);
389 	if (err) {
390 		device_printf(d->dev, "chn_init(%s) failed: err = %d\n", ch->name, err);
391 		kobj_delete(ch->methods, M_DEVBUF);
392 		free(ch, M_DEVBUF);
393 		snd_mtxlock(d->lock);
394 		(*pnum)--;
395 		snd_mtxunlock(d->lock);
396 
397 		return NULL;
398 	}
399 
400 	return ch;
401 }
402 
403 int
404 pcm_chn_destroy(struct pcm_channel *ch)
405 {
406 	struct snddev_info *d;
407 	int err;
408 
409 	d = ch->parentsnddev;
410 	err = chn_kill(ch);
411 	if (err) {
412 		device_printf(d->dev, "chn_kill(%s) failed, err = %d\n", ch->name, err);
413 		return err;
414 	}
415 
416 	kobj_delete(ch->methods, M_DEVBUF);
417 	free(ch, M_DEVBUF);
418 
419 	return 0;
420 }
421 
422 int
423 pcm_chn_add(struct snddev_info *d, struct pcm_channel *ch, int mkdev)
424 {
425     	struct snddev_channel *sce, *tmp, *after;
426     	int unit = device_get_unit(d->dev);
427 	int x = -1;
428 
429 	sce = malloc(sizeof(*sce), M_DEVBUF, M_WAITOK | M_ZERO);
430 	if (!sce) {
431 		return ENOMEM;
432 	}
433 
434 	snd_mtxlock(d->lock);
435 	sce->channel = ch;
436 	if (SLIST_EMPTY(&d->channels)) {
437 		SLIST_INSERT_HEAD(&d->channels, sce, link);
438 	} else {
439 		after = NULL;
440 		SLIST_FOREACH(tmp, &d->channels, link) {
441 			after = tmp;
442 		}
443 		SLIST_INSERT_AFTER(after, sce, link);
444 	}
445 	if (mkdev)
446 		x = d->devcount++;
447 	snd_mtxunlock(d->lock);
448 
449 	if (mkdev) {
450 		dsp_register(unit, x);
451 		if (ch->direction == PCMDIR_REC)
452 			dsp_registerrec(unit, ch->num);
453 	}
454 
455 	return 0;
456 }
457 
458 int
459 pcm_chn_remove(struct snddev_info *d, struct pcm_channel *ch, int rmdev)
460 {
461     	struct snddev_channel *sce;
462     	int unit = device_get_unit(d->dev);
463 
464 	snd_mtxlock(d->lock);
465 	SLIST_FOREACH(sce, &d->channels, link) {
466 		if (sce->channel == ch)
467 			goto gotit;
468 	}
469 	snd_mtxunlock(d->lock);
470 	return EINVAL;
471 gotit:
472 	SLIST_REMOVE(&d->channels, sce, snddev_channel, link);
473 	if (rmdev) {
474 		dsp_unregister(unit, --d->devcount);
475 		if (ch->direction == PCMDIR_REC)
476 			dsp_unregisterrec(unit, ch->num);
477 	}
478 
479     	if (ch->direction == PCMDIR_REC)
480 		d->reccount--;
481 	else if (ch->flags & CHN_F_VIRTUAL)
482 		d->vchancount--;
483 	else
484 		d->playcount--;
485 
486 	snd_mtxunlock(d->lock);
487 	free(sce, M_DEVBUF);
488 
489 	return 0;
490 }
491 
492 int
493 pcm_addchan(device_t dev, int dir, kobj_class_t cls, void *devinfo)
494 {
495     	struct snddev_info *d = device_get_softc(dev);
496 	struct pcm_channel *ch;
497     	int err;
498 
499 	ch = pcm_chn_create(d, NULL, cls, dir, devinfo);
500 	if (!ch) {
501 		device_printf(d->dev, "pcm_chn_create(%s, %d, %p) failed\n", cls->name, dir, devinfo);
502 		return ENODEV;
503 	}
504 
505 	err = pcm_chn_add(d, ch, 1);
506 	if (err) {
507 		device_printf(d->dev, "pcm_chn_add(%s) failed, err=%d\n", ch->name, err);
508 		snd_mtxunlock(d->lock);
509 		pcm_chn_destroy(ch);
510 		return err;
511 	}
512 
513 	if (snd_maxautovchans > 0 && (d->flags & SD_F_AUTOVCHAN) &&
514 	    ch->direction == PCMDIR_PLAY && d->vchancount == 0) {
515 		ch->flags |= CHN_F_BUSY;
516 		err = vchan_create(ch);
517 		if (err) {
518 			device_printf(d->dev, "vchan_create(%s) == %d\n", ch->name, err);
519 			ch->flags &= ~CHN_F_BUSY;
520 		}
521 	}
522 
523 	return err;
524 }
525 
526 static int
527 pcm_killchan(device_t dev)
528 {
529     	struct snddev_info *d = device_get_softc(dev);
530     	struct snddev_channel *sce;
531 	struct pcm_channel *ch;
532 	int error = 0;
533 
534 	snd_mtxlock(d->lock);
535 	sce = SLIST_FIRST(&d->channels);
536 	snd_mtxunlock(d->lock);
537 	ch = sce->channel;
538 
539 	error = pcm_chn_remove(d, sce->channel, SLIST_EMPTY(&ch->children));
540 	if (error)
541 		return (error);
542 	return (pcm_chn_destroy(ch));
543 }
544 
545 int
546 pcm_setstatus(device_t dev, char *str)
547 {
548     	struct snddev_info *d = device_get_softc(dev);
549 
550 	snd_mtxlock(d->lock);
551 	strncpy(d->status, str, SND_STATUSLEN);
552 	snd_mtxunlock(d->lock);
553 	return 0;
554 }
555 
556 u_int32_t
557 pcm_getflags(device_t dev)
558 {
559     	struct snddev_info *d = device_get_softc(dev);
560 
561 	return d->flags;
562 }
563 
564 void
565 pcm_setflags(device_t dev, u_int32_t val)
566 {
567     	struct snddev_info *d = device_get_softc(dev);
568 
569 	d->flags = val;
570 }
571 
572 void *
573 pcm_getdevinfo(device_t dev)
574 {
575     	struct snddev_info *d = device_get_softc(dev);
576 
577 	return d->devinfo;
578 }
579 
580 unsigned int
581 pcm_getbuffersize(device_t dev, unsigned int min, unsigned int deflt, unsigned int max)
582 {
583     	struct snddev_info *d = device_get_softc(dev);
584 	int sz, x;
585 
586 	sz = 0;
587 	if (resource_int_value(device_get_name(dev), device_get_unit(dev), "buffersize", &sz) == 0) {
588 		x = sz;
589 		RANGE(sz, min, max);
590 		if (x != sz)
591 			device_printf(dev, "'buffersize=%d' hint is out of range (%d-%d), using %d\n", x, min, max, sz);
592 		x = min;
593 		while (x < sz)
594 			x <<= 1;
595 		if (x > sz)
596 			x >>= 1;
597 		if (x != sz) {
598 			device_printf(dev, "'buffersize=%d' hint is not a power of 2, using %d\n", sz, x);
599 			sz = x;
600 		}
601 	} else {
602 		sz = deflt;
603 	}
604 
605 	d->bufsz = sz;
606 
607 	return sz;
608 }
609 
610 int
611 pcm_register(device_t dev, void *devinfo, int numplay, int numrec)
612 {
613     	struct snddev_info *d = device_get_softc(dev);
614 
615 	if (pcm_veto_load) {
616 		device_printf(dev, "disabled due to an error while initialising: %d\n", pcm_veto_load);
617 
618 		return EINVAL;
619 	}
620 
621 	d->lock = snd_mtxcreate(device_get_nameunit(dev), "sound cdev");
622 
623 	d->flags = 0;
624 	d->dev = dev;
625 	d->devinfo = devinfo;
626 	d->devcount = 0;
627 	d->reccount = 0;
628 	d->playcount = 0;
629 	d->vchancount = 0;
630 	d->inprog = 0;
631 
632 	if (((numplay == 0) || (numrec == 0)) && (numplay != numrec))
633 		d->flags |= SD_F_SIMPLEX;
634 
635 	d->fakechan = fkchan_setup(dev);
636 	chn_init(d->fakechan, NULL, 0);
637 
638 #ifdef SND_DYNSYSCTL
639 	sysctl_ctx_init(&d->sysctl_tree);
640 	d->sysctl_tree_top = SYSCTL_ADD_NODE(&d->sysctl_tree,
641 				 SYSCTL_STATIC_CHILDREN(_hw_snd), OID_AUTO,
642 				 device_get_nameunit(dev), CTLFLAG_RD, 0, "");
643 	if (d->sysctl_tree_top == NULL) {
644 		sysctl_ctx_free(&d->sysctl_tree);
645 		goto no;
646 	}
647 	SYSCTL_ADD_INT(snd_sysctl_tree(dev), SYSCTL_CHILDREN(snd_sysctl_tree_top(dev)),
648             OID_AUTO, "buffersize", CTLFLAG_RD, &d->bufsz, 0, "");
649 #endif
650 	if (numplay > 0)
651 		vchan_initsys(dev);
652 	if (numplay == 1)
653 		d->flags |= SD_F_AUTOVCHAN;
654 
655 	sndstat_register(dev, d->status, sndstat_prepare_pcm);
656     	return 0;
657 no:
658 	snd_mtxfree(d->lock);
659 	return ENXIO;
660 }
661 
662 int
663 pcm_unregister(device_t dev)
664 {
665     	struct snddev_info *d = device_get_softc(dev);
666     	struct snddev_channel *sce;
667 	struct pcm_channel *ch;
668 
669 	snd_mtxlock(d->lock);
670 	if (d->inprog) {
671 		device_printf(dev, "unregister: operation in progress\n");
672 		snd_mtxunlock(d->lock);
673 		return EBUSY;
674 	}
675 	if (sndstat_busy() != 0) {
676 		device_printf(dev, "unregister: sndstat busy\n");
677 		snd_mtxunlock(d->lock);
678 		return EBUSY;
679 	}
680 	SLIST_FOREACH(sce, &d->channels, link) {
681 		ch = sce->channel;
682 		if (ch->refcount > 0) {
683 			device_printf(dev, "unregister: channel %s busy (pid %d)\n", ch->name, ch->pid);
684 			snd_mtxunlock(d->lock);
685 			return EBUSY;
686 		}
687 	}
688 	if (mixer_uninit(dev)) {
689 		device_printf(dev, "unregister: mixer busy\n");
690 		snd_mtxunlock(d->lock);
691 		return EBUSY;
692 	}
693 
694 #ifdef SND_DYNSYSCTL
695 	d->sysctl_tree_top = NULL;
696 	sysctl_ctx_free(&d->sysctl_tree);
697 #endif
698 	while (!SLIST_EMPTY(&d->channels))
699 		pcm_killchan(dev);
700 
701 	chn_kill(d->fakechan);
702 	fkchan_kill(d->fakechan);
703 
704 	sndstat_unregister(dev);
705 	snd_mtxfree(d->lock);
706 	return 0;
707 }
708 
709 /************************************************************************/
710 
711 static int
712 sndstat_prepare_pcm(struct sbuf *s, device_t dev, int verbose)
713 {
714     	struct snddev_info *d;
715     	struct snddev_channel *sce;
716 	struct pcm_channel *c;
717 	struct pcm_feeder *f;
718     	int pc, rc, vc;
719 
720 	if (verbose < 1)
721 		return 0;
722 
723 	d = device_get_softc(dev);
724 	if (!d)
725 		return ENXIO;
726 
727 	snd_mtxlock(d->lock);
728 	if (!SLIST_EMPTY(&d->channels)) {
729 		pc = rc = vc = 0;
730 		SLIST_FOREACH(sce, &d->channels, link) {
731 			c = sce->channel;
732 			if (c->direction == PCMDIR_PLAY) {
733 				if (c->flags & CHN_F_VIRTUAL)
734 					vc++;
735 				else
736 					pc++;
737 			} else
738 				rc++;
739 		}
740 		sbuf_printf(s, " (%dp/%dr/%dv channels%s%s)", d->playcount, d->reccount, d->vchancount,
741 				(d->flags & SD_F_SIMPLEX)? "" : " duplex",
742 #ifdef USING_DEVFS
743 				(device_get_unit(dev) == snd_unit)? " default" : ""
744 #else
745 				""
746 #endif
747 				);
748 		if (verbose <= 1)
749 			goto skipverbose;
750 		SLIST_FOREACH(sce, &d->channels, link) {
751 			c = sce->channel;
752 			sbuf_printf(s, "\n\t");
753 
754 			sbuf_printf(s, "%s[%s]: ", c->parentchannel? c->parentchannel->name : "", c->name);
755 			sbuf_printf(s, "spd %d", c->speed);
756 			if (c->speed != sndbuf_getspd(c->bufhard))
757 				sbuf_printf(s, "/%d", sndbuf_getspd(c->bufhard));
758 			sbuf_printf(s, ", fmt 0x%08x", c->format);
759 			if (c->format != sndbuf_getfmt(c->bufhard))
760 				sbuf_printf(s, "/0x%08x", sndbuf_getfmt(c->bufhard));
761 			sbuf_printf(s, ", flags %08x", c->flags);
762 			if (c->pid != -1)
763 				sbuf_printf(s, ", pid %d", c->pid);
764 			sbuf_printf(s, "\n\t");
765 
766 			if (c->bufhard != NULL && c->bufsoft != NULL) {
767 				sbuf_printf(s, "interrupts %d, ", c->interrupts);
768 				if (c->direction == PCMDIR_REC)
769 					sbuf_printf(s, "overruns %d, hfree %d, sfree %d",
770 						c->xruns, sndbuf_getfree(c->bufhard), sndbuf_getfree(c->bufsoft));
771 				else
772 					sbuf_printf(s, "underruns %d, ready %d",
773 						c->xruns, sndbuf_getready(c->bufsoft));
774 				sbuf_printf(s, "\n\t");
775 			}
776 
777 			sbuf_printf(s, "{%s}", (c->direction == PCMDIR_REC)? "hardware" : "userland");
778 			sbuf_printf(s, " -> ");
779 			f = c->feeder;
780 			while (f->source != NULL)
781 				f = f->source;
782 			while (f != NULL) {
783 				sbuf_printf(s, "%s", f->class->name);
784 				if (f->desc->type == FEEDER_FMT)
785 					sbuf_printf(s, "(0x%08x -> 0x%08x)", f->desc->in, f->desc->out);
786 				if (f->desc->type == FEEDER_RATE)
787 					sbuf_printf(s, "(%d -> %d)", FEEDER_GET(f, FEEDRATE_SRC), FEEDER_GET(f, FEEDRATE_DST));
788 				if (f->desc->type == FEEDER_ROOT || f->desc->type == FEEDER_MIXER)
789 					sbuf_printf(s, "(0x%08x)", f->desc->out);
790 				sbuf_printf(s, " -> ");
791 				f = f->parent;
792 			}
793 			sbuf_printf(s, "{%s}", (c->direction == PCMDIR_REC)? "userland" : "hardware");
794 		}
795 	} else
796 		sbuf_printf(s, " (mixer only)");
797 skipverbose:
798 	snd_mtxunlock(d->lock);
799 
800 	return 0;
801 }
802 
803 /************************************************************************/
804 
805 #ifdef SND_DYNSYSCTL
806 int
807 sysctl_hw_snd_vchans(SYSCTL_HANDLER_ARGS)
808 {
809 	struct snddev_info *d;
810     	struct snddev_channel *sce;
811 	struct pcm_channel *c;
812 	int err, newcnt, cnt;
813 
814 	d = oidp->oid_arg1;
815 
816 	pcm_lock(d);
817 	cnt = 0;
818 	SLIST_FOREACH(sce, &d->channels, link) {
819 		c = sce->channel;
820 		if ((c->direction == PCMDIR_PLAY) && (c->flags & CHN_F_VIRTUAL))
821 			cnt++;
822 	}
823 	newcnt = cnt;
824 
825 	pcm_unlock(d);
826 	err = sysctl_handle_int(oidp, &newcnt, sizeof(newcnt), req);
827 	pcm_lock(d);
828 	/*
829 	 * Since we dropped the pcm_lock, reload cnt now as it may
830 	 * have changed.
831 	 */
832 	cnt = 0;
833 	SLIST_FOREACH(sce, &d->channels, link) {
834 		c = sce->channel;
835 		if ((c->direction == PCMDIR_PLAY) && (c->flags & CHN_F_VIRTUAL))
836 			cnt++;
837 	}
838 	if (err == 0 && req->newptr != NULL) {
839 		if (newcnt < 0 || newcnt > SND_MAXVCHANS) {
840 			pcm_unlock(d);
841 			return EINVAL;
842 		}
843 
844 		if (newcnt > cnt) {
845 			/* add new vchans - find a parent channel first */
846 			SLIST_FOREACH(sce, &d->channels, link) {
847 				c = sce->channel;
848 				/* not a candidate if not a play channel */
849 				if (c->direction != PCMDIR_PLAY)
850 					continue;
851 				/* not a candidate if a virtual channel */
852 				if (c->flags & CHN_F_VIRTUAL)
853 					continue;
854 				/* not a candidate if it's in use */
855 				if ((c->flags & CHN_F_BUSY) && (SLIST_EMPTY(&c->children)))
856 					continue;
857 				/*
858 				 * if we get here we're a nonvirtual play channel, and either
859 				 * 1) not busy
860 				 * 2) busy with children, not directly open
861 				 *
862 				 * thus we can add children
863 				 */
864 				goto addok;
865 			}
866 			pcm_unlock(d);
867 			return EBUSY;
868 addok:
869 			c->flags |= CHN_F_BUSY;
870 			while (err == 0 && newcnt > cnt) {
871 				err = vchan_create(c);
872 				if (err == 0)
873 					cnt++;
874 			}
875 			if (SLIST_EMPTY(&c->children))
876 				c->flags &= ~CHN_F_BUSY;
877 		} else if (newcnt < cnt) {
878 			while (err == 0 && newcnt < cnt) {
879 				SLIST_FOREACH(sce, &d->channels, link) {
880 					c = sce->channel;
881 					if ((c->flags & (CHN_F_BUSY | CHN_F_VIRTUAL)) == CHN_F_VIRTUAL)
882 						goto remok;
883 				}
884 				pcm_unlock(d);
885 				return EINVAL;
886 remok:
887 				err = vchan_destroy(c);
888 				if (err == 0)
889 					cnt--;
890 			}
891 		}
892 	}
893 
894 	pcm_unlock(d);
895 	return err;
896 }
897 #endif
898 
899 /************************************************************************/
900 
901 static moduledata_t sndpcm_mod = {
902 	"snd_pcm",
903 	NULL,
904 	NULL
905 };
906 DECLARE_MODULE(snd_pcm, sndpcm_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
907 MODULE_VERSION(snd_pcm, PCM_MODVER);
908