xref: /dragonfly/sys/dev/sound/pcm/mixer.c (revision 0cfebe3d)
1 /*-
2  * Copyright (c) 1999 Cameron Grant <cg@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD: src/sys/dev/sound/pcm/mixer.c,v 1.43.2.5 2007/05/13 20:53:39 ariff Exp $
27  * $DragonFly: src/sys/dev/sound/pcm/mixer.c,v 1.18 2007/06/22 21:41:16 corecode Exp $
28  */
29 
30 #include <dev/sound/pcm/sound.h>
31 #include <dev/sound/pcm/dsp.h>
32 
33 #include "mixer_if.h"
34 
35 SND_DECLARE_FILE("$DragonFly: src/sys/dev/sound/pcm/mixer.c,v 1.18 2007/06/22 21:41:16 corecode Exp $");
36 
37 MALLOC_DEFINE(M_MIXER, "mixer", "mixer");
38 
39 #define MIXER_NAMELEN	16
40 struct snd_mixer {
41 	KOBJ_FIELDS;
42 	const char *type;
43 	void *devinfo;
44 	int busy;
45 	int hwvol_muted;
46 	int hwvol_mixer;
47 	int hwvol_step;
48 	device_t dev;
49 	u_int32_t hwvol_mute_level;
50 	u_int32_t devs;
51 	u_int32_t recdevs;
52 	u_int32_t recsrc;
53 	u_int16_t level[32];
54 	u_int8_t parent[32];
55 	u_int32_t child[32];
56 	u_int8_t realdev[32];
57 	char name[MIXER_NAMELEN];
58 	sndlock_t	lock;
59 };
60 
61 static u_int16_t snd_mixerdefaults[SOUND_MIXER_NRDEVICES] = {
62 	[SOUND_MIXER_VOLUME]	= 75,
63 	[SOUND_MIXER_BASS]	= 50,
64 	[SOUND_MIXER_TREBLE]	= 50,
65 	[SOUND_MIXER_SYNTH]	= 75,
66 	[SOUND_MIXER_PCM]	= 75,
67 	[SOUND_MIXER_SPEAKER]	= 75,
68 	[SOUND_MIXER_LINE]	= 75,
69 	[SOUND_MIXER_MIC] 	= 0,
70 	[SOUND_MIXER_CD]	= 75,
71 	[SOUND_MIXER_IGAIN]	= 0,
72 	[SOUND_MIXER_LINE1]	= 75,
73 	[SOUND_MIXER_VIDEO]	= 75,
74 	[SOUND_MIXER_RECLEV]	= 0,
75 	[SOUND_MIXER_OGAIN]	= 50,
76 	[SOUND_MIXER_MONITOR]	= 75,
77 };
78 
79 static char* snd_mixernames[SOUND_MIXER_NRDEVICES] = SOUND_DEVICE_NAMES;
80 
81 static d_open_t mixer_open;
82 static d_close_t mixer_close;
83 
84 static struct dev_ops mixer_cdevsw = {
85 	{ "mixer", SND_CDEV_MAJOR, D_TRACKCLOSE },
86 	/* .d_flags =	D_TRACKCLOSE | D_NEEDGIANT, */
87 	.d_open =	mixer_open,
88 	.d_close =	mixer_close,
89 	.d_ioctl =	mixer_ioctl,
90 };
91 
92 #ifdef USING_DEVFS
93 static eventhandler_tag mixer_ehtag;
94 #endif
95 
96 static struct cdev *
97 mixer_get_devt(device_t dev)
98 {
99 	struct snddev_info *snddev;
100 
101 	snddev = device_get_softc(dev);
102 
103 	return snddev->mixer_dev;
104 }
105 
106 #ifdef SND_DYNSYSCTL
107 static int
108 mixer_lookup(char *devname)
109 {
110 	int i;
111 
112 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++)
113 		if (strncmp(devname, snd_mixernames[i],
114 		    strlen(snd_mixernames[i])) == 0)
115 			return i;
116 	return -1;
117 }
118 #endif
119 
120 /*
121  * Always called with mixer->lock held.
122  */
123 static int
124 mixer_set_softpcmvol(struct snd_mixer *mixer, struct snddev_info *d,
125 						unsigned left, unsigned right)
126 {
127 	struct snddev_channel *sce;
128 	struct pcm_channel *ch;
129 
130 	snd_mtxunlock(mixer->lock);
131 	SLIST_FOREACH(sce, &d->channels, link) {
132 		ch = sce->channel;
133 		CHN_LOCK(ch);
134 		if (ch->direction == PCMDIR_PLAY &&
135 				(ch->feederflags & (1 << FEEDER_VOLUME)))
136 			chn_setvolume(ch, left, right);
137 		CHN_UNLOCK(ch);
138 	}
139         snd_mtxlock(mixer->lock);
140 	return 0;
141 }
142 
143 static int
144 mixer_set(struct snd_mixer *m, unsigned dev, unsigned lev)
145 {
146 	struct snddev_info *d;
147 	unsigned l, r, tl, tr;
148 	u_int32_t parent = SOUND_MIXER_NONE, child = 0;
149 	u_int32_t realdev;
150 	int i;
151 
152 	if (m == NULL || dev >= SOUND_MIXER_NRDEVICES ||
153 	    (0 == (m->devs & (1 << dev))))
154 		return -1;
155 
156 	l = min((lev & 0x00ff), 100);
157 	r = min(((lev & 0xff00) >> 8), 100);
158 	realdev = m->realdev[dev];
159 
160 	d = device_get_softc(m->dev);
161 	if (d == NULL)
162 		return -1;
163 
164 	/* TODO: recursive handling */
165 	parent = m->parent[dev];
166 	if (parent >= SOUND_MIXER_NRDEVICES)
167 		parent = SOUND_MIXER_NONE;
168 	if (parent == SOUND_MIXER_NONE)
169 		child = m->child[dev];
170 
171 	if (parent != SOUND_MIXER_NONE) {
172 		tl = (l * (m->level[parent] & 0x00ff)) / 100;
173 		tr = (r * ((m->level[parent] & 0xff00) >> 8)) / 100;
174 		if (dev == SOUND_MIXER_PCM && (d->flags & SD_F_SOFTPCMVOL))
175 			mixer_set_softpcmvol(m, d, tl, tr);
176 		else if (realdev != SOUND_MIXER_NONE &&
177 		    MIXER_SET(m, realdev, tl, tr) < 0)
178 			return -1;
179 	} else if (child != 0) {
180 		for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
181 			if (!(child & (1 << i)) || m->parent[i] != dev)
182 				continue;
183 			realdev = m->realdev[i];
184 			tl = (l * (m->level[i] & 0x00ff)) / 100;
185 			tr = (r * ((m->level[i] & 0xff00) >> 8)) / 100;
186 			if (i == SOUND_MIXER_PCM && (d->flags & SD_F_SOFTPCMVOL))
187 				mixer_set_softpcmvol(m, d, tl, tr);
188 			else if (realdev != SOUND_MIXER_NONE)
189 				MIXER_SET(m, realdev, tl, tr);
190 		}
191 		realdev = m->realdev[dev];
192 		if (realdev != SOUND_MIXER_NONE &&
193 		    MIXER_SET(m, realdev, l, r) < 0)
194 			return -1;
195 	} else {
196 		if (dev == SOUND_MIXER_PCM && (d->flags & SD_F_SOFTPCMVOL))
197 			mixer_set_softpcmvol(m, d, l, r);
198 		else if (realdev != SOUND_MIXER_NONE &&
199 		    MIXER_SET(m, realdev, l, r) < 0)
200 			return -1;
201 	}
202 
203 	m->level[dev] = l | (r << 8);
204 
205 	return 0;
206 }
207 
208 static int
209 mixer_get(struct snd_mixer *mixer, int dev)
210 {
211 	if ((dev < SOUND_MIXER_NRDEVICES) && (mixer->devs & (1 << dev)))
212 		return mixer->level[dev];
213 	else return -1;
214 }
215 
216 static int
217 mixer_setrecsrc(struct snd_mixer *mixer, u_int32_t src)
218 {
219 	src &= mixer->recdevs;
220 	if (src == 0)
221 		src = SOUND_MASK_MIC;
222 	mixer->recsrc = MIXER_SETRECSRC(mixer, src);
223 	return 0;
224 }
225 
226 static int
227 mixer_getrecsrc(struct snd_mixer *mixer)
228 {
229 	return mixer->recsrc;
230 }
231 
232 void
233 mix_setdevs(struct snd_mixer *m, u_int32_t v)
234 {
235 	struct snddev_info *d;
236 	int i;
237 
238 	if (m == NULL)
239 		return;
240 
241 	d = device_get_softc(m->dev);
242 	if (d != NULL && (d->flags & SD_F_SOFTPCMVOL))
243 		v |= SOUND_MASK_PCM;
244 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
245 		if (m->parent[i] < SOUND_MIXER_NRDEVICES)
246 			v |= 1 << m->parent[i];
247 		v |= m->child[i];
248 	}
249 	m->devs = v;
250 }
251 
252 void
253 mix_setrecdevs(struct snd_mixer *m, u_int32_t v)
254 {
255 	m->recdevs = v;
256 }
257 
258 void
259 mix_setparentchild(struct snd_mixer *m, u_int32_t parent, u_int32_t childs)
260 {
261 	u_int32_t mask = 0;
262 	int i;
263 
264 	if (m == NULL || parent >= SOUND_MIXER_NRDEVICES)
265 		return;
266 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
267 		if (i == parent)
268 			continue;
269 		if (childs & (1 << i)) {
270 			mask |= 1 << i;
271 			if (m->parent[i] < SOUND_MIXER_NRDEVICES)
272 				m->child[m->parent[i]] &= ~(1 << i);
273 			m->parent[i] = parent;
274 			m->child[i] = 0;
275 		}
276 	}
277 	mask &= ~(1 << parent);
278 	m->child[parent] = mask;
279 }
280 
281 void
282 mix_setrealdev(struct snd_mixer *m, u_int32_t dev, u_int32_t realdev)
283 {
284 	if (m == NULL || dev >= SOUND_MIXER_NRDEVICES ||
285 	    !(realdev == SOUND_MIXER_NONE || realdev < SOUND_MIXER_NRDEVICES))
286 		return;
287 	m->realdev[dev] = realdev;
288 }
289 
290 u_int32_t
291 mix_getparent(struct snd_mixer *m, u_int32_t dev)
292 {
293 	if (m == NULL || dev >= SOUND_MIXER_NRDEVICES)
294 		return SOUND_MIXER_NONE;
295 	return m->parent[dev];
296 }
297 
298 u_int32_t
299 mix_getchild(struct snd_mixer *m, u_int32_t dev)
300 {
301 	if (m == NULL || dev >= SOUND_MIXER_NRDEVICES)
302 		return 0;
303 	return m->child[dev];
304 }
305 
306 u_int32_t
307 mix_getdevs(struct snd_mixer *m)
308 {
309 	return m->devs;
310 }
311 
312 u_int32_t
313 mix_getrecdevs(struct snd_mixer *m)
314 {
315 	return m->recdevs;
316 }
317 
318 void *
319 mix_getdevinfo(struct snd_mixer *m)
320 {
321 	return m->devinfo;
322 }
323 
324 int
325 mixer_init(device_t dev, kobj_class_t cls, void *devinfo)
326 {
327 	struct snddev_info *snddev;
328 	struct snd_mixer *m;
329 	u_int16_t v;
330 	struct cdev *pdev;
331 	int i, unit, val;
332 
333 	m = (struct snd_mixer *)kobj_create(cls, M_MIXER, M_WAITOK | M_ZERO);
334 	ksnprintf(m->name, MIXER_NAMELEN, "%s:mixer", device_get_nameunit(dev));
335 	m->lock = snd_mtxcreate(m->name, "pcm mixer");
336 	m->type = cls->name;
337 	m->devinfo = devinfo;
338 	m->busy = 0;
339 	m->dev = dev;
340 	for (i = 0; i < 32; i++) {
341 		m->parent[i] = SOUND_MIXER_NONE;
342 		m->child[i] = 0;
343 		m->realdev[i] = i;
344 	}
345 
346 	if (MIXER_INIT(m))
347 		goto bad;
348 
349 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
350 		v = snd_mixerdefaults[i];
351 
352 		if (resource_int_value(device_get_name(dev),
353 		    device_get_unit(dev), snd_mixernames[i], &val) == 0) {
354 			if (val >= 0 && val <= 100) {
355 				v = (u_int16_t) val;
356 			}
357 		}
358 
359 		snd_mtxlock(m->lock);
360 		mixer_set(m, i, v | (v << 8));
361 		snd_mtxunlock(m->lock);
362 	}
363 
364 	mixer_setrecsrc(m, SOUND_MASK_MIC);
365 
366 	unit = device_get_unit(dev);
367 	dev_ops_add(&mixer_cdevsw, -1, PCMMKMINOR(unit, SND_DEV_CTL, 0));
368 	pdev = make_dev(&mixer_cdevsw, PCMMKMINOR(unit, SND_DEV_CTL, 0),
369 		 UID_ROOT, GID_WHEEL, 0666, "mixer%d", unit);
370 	reference_dev(pdev);
371 	pdev->si_drv1 = m;
372 	snddev = device_get_softc(dev);
373 	snddev->mixer_dev = pdev;
374 
375 	if (bootverbose) {
376 		for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
377 			if (!(m->devs & (1 << i)))
378 				continue;
379 			if (m->realdev[i] != i) {
380 				device_printf(dev, "Mixer \"%s\" -> \"%s\":",
381 				    snd_mixernames[i],
382 				    (m->realdev[i] < SOUND_MIXER_NRDEVICES) ?
383 				    snd_mixernames[m->realdev[i]] : "none");
384 			} else {
385 				device_printf(dev, "Mixer \"%s\":",
386 				    snd_mixernames[i]);
387 			}
388 			if (m->parent[i] < SOUND_MIXER_NRDEVICES)
389 				kprintf(" parent=\"%s\"",
390 				    snd_mixernames[m->parent[i]]);
391 			if (m->child[i] != 0)
392 				kprintf(" child=0x%08x", m->child[i]);
393 			kprintf("\n");
394 		}
395 		if (snddev->flags & SD_F_SOFTPCMVOL)
396 			device_printf(dev, "Soft PCM mixer ENABLED\n");
397 	}
398 
399 	return 0;
400 
401 bad:
402 	snd_mtxfree(m->lock);
403 	kobj_delete((kobj_t)m, M_MIXER);
404 	return -1;
405 }
406 
407 int
408 mixer_uninit(device_t dev)
409 {
410 	int i;
411 	int unit;
412 	struct snddev_info *d;
413 	struct snd_mixer *m;
414 	struct cdev *pdev;
415 
416 	d = device_get_softc(dev);
417 	pdev = mixer_get_devt(dev);
418 	if (d == NULL || pdev == NULL || pdev->si_drv1 == NULL)
419 		return EBADF;
420 	m = pdev->si_drv1;
421 	snd_mtxlock(m->lock);
422 
423 	if (m->busy) {
424 		snd_mtxunlock(m->lock);
425 		return EBUSY;
426 	}
427 
428 	pdev->si_drv1 = NULL;
429 	release_dev(pdev);
430 	unit = device_get_unit(dev);
431 	dev_ops_remove(&mixer_cdevsw, -1, PCMMKMINOR(unit, SND_DEV_CTL, 0));
432 
433 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++)
434 		mixer_set(m, i, 0);
435 
436 	mixer_setrecsrc(m, SOUND_MASK_MIC);
437 
438 	MIXER_UNINIT(m);
439 
440 	snd_mtxunlock(m->lock);
441 	snd_mtxfree(m->lock);
442 	kobj_delete((kobj_t)m, M_MIXER);
443 
444 	d->mixer_dev = NULL;
445 
446 	return 0;
447 }
448 
449 int
450 mixer_reinit(device_t dev)
451 {
452 	struct snd_mixer *m;
453 	struct cdev *pdev;
454 	int i;
455 
456 	pdev = mixer_get_devt(dev);
457 	m = pdev->si_drv1;
458 	snd_mtxlock(m->lock);
459 
460 	i = MIXER_REINIT(m);
461 	if (i) {
462 		snd_mtxunlock(m->lock);
463 		return i;
464 	}
465 
466 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++)
467 		mixer_set(m, i, m->level[i]);
468 
469 	mixer_setrecsrc(m, m->recsrc);
470 	snd_mtxunlock(m->lock);
471 
472 	return 0;
473 }
474 
475 #ifdef SND_DYNSYSCTL
476 static int
477 sysctl_hw_snd_hwvol_mixer(SYSCTL_HANDLER_ARGS)
478 {
479 	char devname[32];
480 	int error, dev;
481 	struct snd_mixer *m;
482 
483 	m = oidp->oid_arg1;
484 	snd_mtxlock(m->lock);
485 	strncpy(devname, snd_mixernames[m->hwvol_mixer], sizeof(devname));
486 	snd_mtxunlock(m->lock);
487 	error = sysctl_handle_string(oidp, &devname[0], sizeof(devname), req);
488 	snd_mtxlock(m->lock);
489 	if (error == 0 && req->newptr != NULL) {
490 		dev = mixer_lookup(devname);
491 		if (dev == -1) {
492 			snd_mtxunlock(m->lock);
493 			return EINVAL;
494 		}
495 		else if (dev != m->hwvol_mixer) {
496 			m->hwvol_mixer = dev;
497 			m->hwvol_muted = 0;
498 		}
499 	}
500 	snd_mtxunlock(m->lock);
501 	return error;
502 }
503 #endif
504 
505 int
506 mixer_hwvol_init(device_t dev)
507 {
508 	struct snd_mixer *m;
509 	struct cdev *pdev;
510 
511 	pdev = mixer_get_devt(dev);
512 	m = pdev->si_drv1;
513 
514 	m->hwvol_mixer = SOUND_MIXER_VOLUME;
515 	m->hwvol_step = 5;
516 #ifdef SND_DYNSYSCTL
517 	SYSCTL_ADD_INT(snd_sysctl_tree(dev), SYSCTL_CHILDREN(snd_sysctl_tree_top(dev)),
518             OID_AUTO, "hwvol_step", CTLFLAG_RW, &m->hwvol_step, 0, "");
519 	SYSCTL_ADD_PROC(snd_sysctl_tree(dev), SYSCTL_CHILDREN(snd_sysctl_tree_top(dev)),
520             OID_AUTO, "hwvol_mixer", CTLTYPE_STRING | CTLFLAG_RW, m, 0,
521 	    sysctl_hw_snd_hwvol_mixer, "A", "");
522 #endif
523 	return 0;
524 }
525 
526 void
527 mixer_hwvol_mute(device_t dev)
528 {
529 	struct snd_mixer *m;
530 	struct cdev *pdev;
531 
532 	pdev = mixer_get_devt(dev);
533 	m = pdev->si_drv1;
534 	snd_mtxlock(m->lock);
535 	if (m->hwvol_muted) {
536 		m->hwvol_muted = 0;
537 		mixer_set(m, m->hwvol_mixer, m->hwvol_mute_level);
538 	} else {
539 		m->hwvol_muted++;
540 		m->hwvol_mute_level = mixer_get(m, m->hwvol_mixer);
541 		mixer_set(m, m->hwvol_mixer, 0);
542 	}
543 	snd_mtxunlock(m->lock);
544 }
545 
546 void
547 mixer_hwvol_step(device_t dev, int left_step, int right_step)
548 {
549 	struct snd_mixer *m;
550 	int level, left, right;
551 	struct cdev *pdev;
552 
553 	pdev = mixer_get_devt(dev);
554 	m = pdev->si_drv1;
555 	snd_mtxlock(m->lock);
556 	if (m->hwvol_muted) {
557 		m->hwvol_muted = 0;
558 		level = m->hwvol_mute_level;
559 	} else
560 		level = mixer_get(m, m->hwvol_mixer);
561 	if (level != -1) {
562 		left = level & 0xff;
563 		right = level >> 8;
564 		left += left_step * m->hwvol_step;
565 		if (left < 0)
566 			left = 0;
567 		right += right_step * m->hwvol_step;
568 		if (right < 0)
569 			right = 0;
570 		mixer_set(m, m->hwvol_mixer, left | right << 8);
571 	}
572 	snd_mtxunlock(m->lock);
573 }
574 
575 /* ----------------------------------------------------------------------- */
576 
577 static int
578 vchanvolume(cdev_t i_dev, int write, int *volume, int *ret,
579 		struct thread *td)
580 {
581 	struct snddev_info *d;
582 	void *cookie;
583 	struct pcm_channel *ch;
584 	int vol_left, vol_right;
585 
586 	crit_enter();
587 	d = dsp_get_info(i_dev);
588 	if (d == NULL) {
589 		crit_exit();
590 		return 0;
591 	}
592 	/*
593 	 * We search for a vchan which is owned by the current process.
594 	 */
595 	for (cookie = NULL; (ch = pcm_chn_iterate(d, &cookie)) != NULL;)
596 		if (ch->flags & CHN_F_VIRTUAL &&
597 		    ch->pid == td->td_proc->p_pid)
598 			break;
599 
600 	if (ch == NULL) {
601 		crit_exit();
602 		return 0;
603 	}
604 
605 	if (write) {
606 		vol_left = min(*volume & 0x00ff, 100);
607 		vol_right = min((*volume & 0xff00) >> 8, 100);
608 		*ret = chn_setvolume(ch, vol_left, vol_right);
609 	} else {
610 		*volume = ch->volume;
611 		*ret = 0;
612 	}
613 	crit_exit();
614 	return 1;
615 }
616 
617 /* ----------------------------------------------------------------------- */
618 
619 static int
620 mixer_open(struct dev_open_args *ap)
621 {
622 	struct cdev *i_dev = ap->a_head.a_dev;
623 	struct snd_mixer *m;
624 
625 	m = i_dev->si_drv1;
626 	snd_mtxlock(m->lock);
627 
628 	m->busy++;
629 
630 	snd_mtxunlock(m->lock);
631 	return 0;
632 }
633 
634 static int
635 mixer_close(struct dev_close_args *ap)
636 {
637 	struct cdev *i_dev = ap->a_head.a_dev;
638 	struct snd_mixer *m;
639 
640 	m = i_dev->si_drv1;
641 	snd_mtxlock(m->lock);
642 
643 	if (!m->busy) {
644 		snd_mtxunlock(m->lock);
645 		return EBADF;
646 	}
647 	m->busy--;
648 
649 	snd_mtxunlock(m->lock);
650 	return 0;
651 }
652 
653 int
654 mixer_ioctl(struct dev_ioctl_args *ap)
655 {
656 	struct cdev *i_dev = ap->a_head.a_dev;
657 	u_long cmd = ap->a_cmd;
658 	caddr_t arg = ap->a_data;
659 	int mode = ap->a_fflag;
660 	struct snd_mixer *m;
661 	int ret, *arg_i = (int *)arg;
662 	int v = -1, j = cmd & 0xff;
663 
664 	m = i_dev->si_drv1;
665 
666 	if (m == NULL)
667 		return EBADF;
668 
669 	/*
670 	 * If we are handling PCM, maybe the app really wants to
671 	 * set its vchan, and fails to use the correct fd.
672 	 */
673 	if (j == SOUND_MIXER_PCM) {
674 		if (vchanvolume(i_dev,
675 			    (cmd & MIXER_WRITE(0)) == MIXER_WRITE(0),
676 			    (int *)arg, &ret, curthread))
677 			return ret;
678 		/* else proceed as usual */
679 	}
680 
681 	snd_mtxlock(m->lock);
682 	if (mode != -1 && !m->busy) {
683 		snd_mtxunlock(m->lock);
684 		return EBADF;
685 	}
686 
687 	if ((cmd & MIXER_WRITE(0)) == MIXER_WRITE(0)) {
688 		if (j == SOUND_MIXER_RECSRC)
689 			ret = mixer_setrecsrc(m, *arg_i);
690 		else
691 			ret = mixer_set(m, j, *arg_i);
692 		snd_mtxunlock(m->lock);
693 		return (ret == 0)? 0 : ENXIO;
694 	}
695 
696     	if ((cmd & MIXER_READ(0)) == MIXER_READ(0)) {
697 		switch (j) {
698     		case SOUND_MIXER_DEVMASK:
699     		case SOUND_MIXER_CAPS:
700     		case SOUND_MIXER_STEREODEVS:
701 			v = mix_getdevs(m);
702 			break;
703 
704     		case SOUND_MIXER_RECMASK:
705 			v = mix_getrecdevs(m);
706 			break;
707 
708     		case SOUND_MIXER_RECSRC:
709 			v = mixer_getrecsrc(m);
710 			break;
711 
712 		default:
713 			v = mixer_get(m, j);
714 		}
715 		*arg_i = v;
716 		snd_mtxunlock(m->lock);
717 		return (v != -1)? 0 : ENXIO;
718 	}
719 	snd_mtxunlock(m->lock);
720 	return ENXIO;
721 }
722 
723 #ifdef USING_DEVFS
724 static void
725 mixer_clone(void *arg, struct ucred *cred, char *name, int namelen,
726     struct cdev **dev)
727 {
728 	struct snddev_info *sd;
729 
730 	if (*dev != NULL)
731 		return;
732 	if (strcmp(name, "mixer") == 0) {
733 		sd = devclass_get_softc(pcm_devclass, snd_unit);
734 		if (sd != NULL && sd->mixer_dev != NULL) {
735 			*dev = sd->mixer_dev;
736 			dev_ref(*dev);
737 		}
738 	}
739 }
740 
741 static void
742 mixer_sysinit(void *p)
743 {
744 	mixer_ehtag = EVENTHANDLER_REGISTER(dev_clone, mixer_clone, 0, 1000);
745 }
746 
747 static void
748 mixer_sysuninit(void *p)
749 {
750 	if (mixer_ehtag != NULL)
751 		EVENTHANDLER_DEREGISTER(dev_clone, mixer_ehtag);
752 }
753 
754 SYSINIT(mixer_sysinit, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, mixer_sysinit, NULL);
755 SYSUNINIT(mixer_sysuninit, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, mixer_sysuninit, NULL);
756 #endif
757 
758 
759