xref: /freebsd/sys/dev/sound/pcm/mixer.c (revision d6b92ffa)
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  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #ifdef HAVE_KERNEL_OPTION_HEADERS
30 #include "opt_snd.h"
31 #endif
32 
33 #include <dev/sound/pcm/sound.h>
34 
35 #include "feeder_if.h"
36 #include "mixer_if.h"
37 
38 SND_DECLARE_FILE("$FreeBSD$");
39 
40 static MALLOC_DEFINE(M_MIXER, "mixer", "mixer");
41 
42 static int mixer_bypass = 1;
43 SYSCTL_INT(_hw_snd, OID_AUTO, vpc_mixer_bypass, CTLFLAG_RWTUN,
44     &mixer_bypass, 0,
45     "control channel pcm/rec volume, bypassing real mixer device");
46 
47 #define MIXER_NAMELEN	16
48 struct snd_mixer {
49 	KOBJ_FIELDS;
50 	void *devinfo;
51 	int busy;
52 	int hwvol_muted;
53 	int hwvol_mixer;
54 	int hwvol_step;
55 	int type;
56 	device_t dev;
57 	u_int32_t hwvol_mute_level;
58 	u_int32_t devs;
59 	u_int32_t recdevs;
60 	u_int32_t recsrc;
61 	u_int16_t level[32];
62 	u_int8_t parent[32];
63 	u_int32_t child[32];
64 	u_int8_t realdev[32];
65 	char name[MIXER_NAMELEN];
66 	struct mtx *lock;
67 	oss_mixer_enuminfo enuminfo;
68 	/**
69 	 * Counter is incremented when applications change any of this
70 	 * mixer's controls.  A change in value indicates that persistent
71 	 * mixer applications should update their displays.
72 	 */
73 	int modify_counter;
74 };
75 
76 static u_int16_t snd_mixerdefaults[SOUND_MIXER_NRDEVICES] = {
77 	[SOUND_MIXER_VOLUME]	= 75,
78 	[SOUND_MIXER_BASS]	= 50,
79 	[SOUND_MIXER_TREBLE]	= 50,
80 	[SOUND_MIXER_SYNTH]	= 75,
81 	[SOUND_MIXER_PCM]	= 75,
82 	[SOUND_MIXER_SPEAKER]	= 75,
83 	[SOUND_MIXER_LINE]	= 75,
84 	[SOUND_MIXER_MIC] 	= 0,
85 	[SOUND_MIXER_CD]	= 75,
86 	[SOUND_MIXER_IGAIN]	= 0,
87 	[SOUND_MIXER_LINE1]	= 75,
88 	[SOUND_MIXER_VIDEO]	= 75,
89 	[SOUND_MIXER_RECLEV]	= 75,
90 	[SOUND_MIXER_OGAIN]	= 50,
91 	[SOUND_MIXER_MONITOR]	= 75,
92 };
93 
94 static char* snd_mixernames[SOUND_MIXER_NRDEVICES] = SOUND_DEVICE_NAMES;
95 
96 static d_open_t mixer_open;
97 static d_close_t mixer_close;
98 static d_ioctl_t mixer_ioctl;
99 
100 static struct cdevsw mixer_cdevsw = {
101 	.d_version =	D_VERSION,
102 	.d_open =	mixer_open,
103 	.d_close =	mixer_close,
104 	.d_ioctl =	mixer_ioctl,
105 	.d_name =	"mixer",
106 };
107 
108 /**
109  * Keeps a count of mixer devices; used only by OSSv4 SNDCTL_SYSINFO ioctl.
110  */
111 int mixer_count = 0;
112 
113 static eventhandler_tag mixer_ehtag = NULL;
114 
115 static struct cdev *
116 mixer_get_devt(device_t dev)
117 {
118 	struct snddev_info *snddev;
119 
120 	snddev = device_get_softc(dev);
121 
122 	return snddev->mixer_dev;
123 }
124 
125 static int
126 mixer_lookup(char *devname)
127 {
128 	int i;
129 
130 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++)
131 		if (strncmp(devname, snd_mixernames[i],
132 		    strlen(snd_mixernames[i])) == 0)
133 			return i;
134 	return -1;
135 }
136 
137 #define MIXER_SET_UNLOCK(x, y)		do {				\
138 	if ((y) != 0)							\
139 		snd_mtxunlock((x)->lock);				\
140 } while (0)
141 
142 #define MIXER_SET_LOCK(x, y)		do {				\
143 	if ((y) != 0)							\
144 		snd_mtxlock((x)->lock);					\
145 } while (0)
146 
147 static int
148 mixer_set_softpcmvol(struct snd_mixer *m, struct snddev_info *d,
149     u_int left, u_int right)
150 {
151 	struct pcm_channel *c;
152 	int dropmtx, acquiremtx;
153 
154 	if (!PCM_REGISTERED(d))
155 		return (EINVAL);
156 
157 	if (mtx_owned(m->lock))
158 		dropmtx = 1;
159 	else
160 		dropmtx = 0;
161 
162 	if (!(d->flags & SD_F_MPSAFE) || mtx_owned(d->lock) != 0)
163 		acquiremtx = 0;
164 	else
165 		acquiremtx = 1;
166 
167 	/*
168 	 * Be careful here. If we're coming from cdev ioctl, it is OK to
169 	 * not doing locking AT ALL (except on individual channel) since
170 	 * we've been heavily guarded by pcm cv, or if we're still
171 	 * under Giant influence. Since we also have mix_* calls, we cannot
172 	 * assume such protection and just do the lock as usuall.
173 	 */
174 	MIXER_SET_UNLOCK(m, dropmtx);
175 	MIXER_SET_LOCK(d, acquiremtx);
176 
177 	CHN_FOREACH(c, d, channels.pcm.busy) {
178 		CHN_LOCK(c);
179 		if (c->direction == PCMDIR_PLAY &&
180 		    (c->feederflags & (1 << FEEDER_VOLUME)))
181 			chn_setvolume_multi(c, SND_VOL_C_MASTER, left, right,
182 			    (left + right) >> 1);
183 		CHN_UNLOCK(c);
184 	}
185 
186 	MIXER_SET_UNLOCK(d, acquiremtx);
187 	MIXER_SET_LOCK(m, dropmtx);
188 
189 	return (0);
190 }
191 
192 static int
193 mixer_set_eq(struct snd_mixer *m, struct snddev_info *d,
194     u_int dev, u_int level)
195 {
196 	struct pcm_channel *c;
197 	struct pcm_feeder *f;
198 	int tone, dropmtx, acquiremtx;
199 
200 	if (dev == SOUND_MIXER_TREBLE)
201 		tone = FEEDEQ_TREBLE;
202 	else if (dev == SOUND_MIXER_BASS)
203 		tone = FEEDEQ_BASS;
204 	else
205 		return (EINVAL);
206 
207 	if (!PCM_REGISTERED(d))
208 		return (EINVAL);
209 
210 	if (mtx_owned(m->lock))
211 		dropmtx = 1;
212 	else
213 		dropmtx = 0;
214 
215 	if (!(d->flags & SD_F_MPSAFE) || mtx_owned(d->lock) != 0)
216 		acquiremtx = 0;
217 	else
218 		acquiremtx = 1;
219 
220 	/*
221 	 * Be careful here. If we're coming from cdev ioctl, it is OK to
222 	 * not doing locking AT ALL (except on individual channel) since
223 	 * we've been heavily guarded by pcm cv, or if we're still
224 	 * under Giant influence. Since we also have mix_* calls, we cannot
225 	 * assume such protection and just do the lock as usuall.
226 	 */
227 	MIXER_SET_UNLOCK(m, dropmtx);
228 	MIXER_SET_LOCK(d, acquiremtx);
229 
230 	CHN_FOREACH(c, d, channels.pcm.busy) {
231 		CHN_LOCK(c);
232 		f = chn_findfeeder(c, FEEDER_EQ);
233 		if (f != NULL)
234 			(void)FEEDER_SET(f, tone, level);
235 		CHN_UNLOCK(c);
236 	}
237 
238 	MIXER_SET_UNLOCK(d, acquiremtx);
239 	MIXER_SET_LOCK(m, dropmtx);
240 
241 	return (0);
242 }
243 
244 static int
245 mixer_set(struct snd_mixer *m, u_int dev, u_int lev)
246 {
247 	struct snddev_info *d;
248 	u_int l, r, tl, tr;
249 	u_int32_t parent = SOUND_MIXER_NONE, child = 0;
250 	u_int32_t realdev;
251 	int i, dropmtx;
252 
253 	if (m == NULL || dev >= SOUND_MIXER_NRDEVICES ||
254 	    (0 == (m->devs & (1 << dev))))
255 		return -1;
256 
257 	l = min((lev & 0x00ff), 100);
258 	r = min(((lev & 0xff00) >> 8), 100);
259 	realdev = m->realdev[dev];
260 
261 	d = device_get_softc(m->dev);
262 	if (d == NULL)
263 		return -1;
264 
265 	/* It is safe to drop this mutex due to Giant. */
266 	if (!(d->flags & SD_F_MPSAFE) && mtx_owned(m->lock) != 0)
267 		dropmtx = 1;
268 	else
269 		dropmtx = 0;
270 
271 	MIXER_SET_UNLOCK(m, dropmtx);
272 
273 	/* TODO: recursive handling */
274 	parent = m->parent[dev];
275 	if (parent >= SOUND_MIXER_NRDEVICES)
276 		parent = SOUND_MIXER_NONE;
277 	if (parent == SOUND_MIXER_NONE)
278 		child = m->child[dev];
279 
280 	if (parent != SOUND_MIXER_NONE) {
281 		tl = (l * (m->level[parent] & 0x00ff)) / 100;
282 		tr = (r * ((m->level[parent] & 0xff00) >> 8)) / 100;
283 		if (dev == SOUND_MIXER_PCM && (d->flags & SD_F_SOFTPCMVOL))
284 			(void)mixer_set_softpcmvol(m, d, tl, tr);
285 		else if (realdev != SOUND_MIXER_NONE &&
286 		    MIXER_SET(m, realdev, tl, tr) < 0) {
287 			MIXER_SET_LOCK(m, dropmtx);
288 			return -1;
289 		}
290 	} else if (child != 0) {
291 		for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
292 			if (!(child & (1 << i)) || m->parent[i] != dev)
293 				continue;
294 			realdev = m->realdev[i];
295 			tl = (l * (m->level[i] & 0x00ff)) / 100;
296 			tr = (r * ((m->level[i] & 0xff00) >> 8)) / 100;
297 			if (i == SOUND_MIXER_PCM &&
298 			    (d->flags & SD_F_SOFTPCMVOL))
299 				(void)mixer_set_softpcmvol(m, d, tl, tr);
300 			else if (realdev != SOUND_MIXER_NONE)
301 				MIXER_SET(m, realdev, tl, tr);
302 		}
303 		realdev = m->realdev[dev];
304 		if (realdev != SOUND_MIXER_NONE &&
305 		    MIXER_SET(m, realdev, l, r) < 0) {
306 				MIXER_SET_LOCK(m, dropmtx);
307 				return -1;
308 		}
309 	} else {
310 		if (dev == SOUND_MIXER_PCM && (d->flags & SD_F_SOFTPCMVOL))
311 			(void)mixer_set_softpcmvol(m, d, l, r);
312 		else if ((dev == SOUND_MIXER_TREBLE ||
313 		    dev == SOUND_MIXER_BASS) && (d->flags & SD_F_EQ))
314 			(void)mixer_set_eq(m, d, dev, (l + r) >> 1);
315 		else if (realdev != SOUND_MIXER_NONE &&
316 		    MIXER_SET(m, realdev, l, r) < 0) {
317 			MIXER_SET_LOCK(m, dropmtx);
318 			return -1;
319 		}
320 	}
321 
322 	MIXER_SET_LOCK(m, dropmtx);
323 
324 	m->level[dev] = l | (r << 8);
325 
326 	return 0;
327 }
328 
329 static int
330 mixer_get(struct snd_mixer *mixer, int dev)
331 {
332 	if ((dev < SOUND_MIXER_NRDEVICES) && (mixer->devs & (1 << dev)))
333 		return mixer->level[dev];
334 	else
335 		return -1;
336 }
337 
338 static int
339 mixer_setrecsrc(struct snd_mixer *mixer, u_int32_t src)
340 {
341 	struct snddev_info *d;
342 	u_int32_t recsrc;
343 	int dropmtx;
344 
345 	d = device_get_softc(mixer->dev);
346 	if (d == NULL)
347 		return -1;
348 	if (!(d->flags & SD_F_MPSAFE) && mtx_owned(mixer->lock) != 0)
349 		dropmtx = 1;
350 	else
351 		dropmtx = 0;
352 	src &= mixer->recdevs;
353 	if (src == 0)
354 		src = mixer->recdevs & SOUND_MASK_MIC;
355 	if (src == 0)
356 		src = mixer->recdevs & SOUND_MASK_MONITOR;
357 	if (src == 0)
358 		src = mixer->recdevs & SOUND_MASK_LINE;
359 	if (src == 0 && mixer->recdevs != 0)
360 		src = (1 << (ffs(mixer->recdevs) - 1));
361 	/* It is safe to drop this mutex due to Giant. */
362 	MIXER_SET_UNLOCK(mixer, dropmtx);
363 	recsrc = MIXER_SETRECSRC(mixer, src);
364 	MIXER_SET_LOCK(mixer, dropmtx);
365 
366 	mixer->recsrc = recsrc;
367 
368 	return 0;
369 }
370 
371 static int
372 mixer_getrecsrc(struct snd_mixer *mixer)
373 {
374 	return mixer->recsrc;
375 }
376 
377 /**
378  * @brief Retrieve the route number of the current recording device
379  *
380  * OSSv4 assigns routing numbers to recording devices, unlike the previous
381  * API which relied on a fixed table of device numbers and names.  This
382  * function returns the routing number of the device currently selected
383  * for recording.
384  *
385  * For now, this function is kind of a goofy compatibility stub atop the
386  * existing sound system.  (For example, in theory, the old sound system
387  * allows multiple recording devices to be specified via a bitmask.)
388  *
389  * @param m	mixer context container thing
390  *
391  * @retval 0		success
392  * @retval EIDRM	no recording device found (generally not possible)
393  * @todo Ask about error code
394  */
395 static int
396 mixer_get_recroute(struct snd_mixer *m, int *route)
397 {
398 	int i, cnt;
399 
400 	cnt = 0;
401 
402 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
403 		/** @todo can user set a multi-device mask? (== or &?) */
404 		if ((1 << i) == m->recsrc)
405 			break;
406 		if ((1 << i) & m->recdevs)
407 			++cnt;
408 	}
409 
410 	if (i == SOUND_MIXER_NRDEVICES)
411 		return EIDRM;
412 
413 	*route = cnt;
414 	return 0;
415 }
416 
417 /**
418  * @brief Select a device for recording
419  *
420  * This function sets a recording source based on a recording device's
421  * routing number.  Said number is translated to an old school recdev
422  * mask and passed over mixer_setrecsrc.
423  *
424  * @param m	mixer context container thing
425  *
426  * @retval 0		success(?)
427  * @retval EINVAL	User specified an invalid device number
428  * @retval otherwise	error from mixer_setrecsrc
429  */
430 static int
431 mixer_set_recroute(struct snd_mixer *m, int route)
432 {
433 	int i, cnt, ret;
434 
435 	ret = 0;
436 	cnt = 0;
437 
438 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
439 		if ((1 << i) & m->recdevs) {
440 			if (route == cnt)
441 				break;
442 			++cnt;
443 		}
444 	}
445 
446 	if (i == SOUND_MIXER_NRDEVICES)
447 		ret = EINVAL;
448 	else
449 		ret = mixer_setrecsrc(m, (1 << i));
450 
451 	return ret;
452 }
453 
454 void
455 mix_setdevs(struct snd_mixer *m, u_int32_t v)
456 {
457 	struct snddev_info *d;
458 	int i;
459 
460 	if (m == NULL)
461 		return;
462 
463 	d = device_get_softc(m->dev);
464 	if (d != NULL && (d->flags & SD_F_SOFTPCMVOL))
465 		v |= SOUND_MASK_PCM;
466 	if (d != NULL && (d->flags & SD_F_EQ))
467 		v |= SOUND_MASK_TREBLE | SOUND_MASK_BASS;
468 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
469 		if (m->parent[i] < SOUND_MIXER_NRDEVICES)
470 			v |= 1 << m->parent[i];
471 		v |= m->child[i];
472 	}
473 	m->devs = v;
474 }
475 
476 /**
477  * @brief Record mask of available recording devices
478  *
479  * Calling functions are responsible for defining the mask of available
480  * recording devices.  This function records that value in a structure
481  * used by the rest of the mixer code.
482  *
483  * This function also populates a structure used by the SNDCTL_DSP_*RECSRC*
484  * family of ioctls that are part of OSSV4.  All recording device labels
485  * are concatenated in ascending order corresponding to their routing
486  * numbers.  (Ex:  a system might have 0 => 'vol', 1 => 'cd', 2 => 'line',
487  * etc.)  For now, these labels are just the standard recording device
488  * names (cd, line1, etc.), but will eventually be fully dynamic and user
489  * controlled.
490  *
491  * @param m	mixer device context container thing
492  * @param v	mask of recording devices
493  */
494 void
495 mix_setrecdevs(struct snd_mixer *m, u_int32_t v)
496 {
497 	oss_mixer_enuminfo *ei;
498 	char *loc;
499 	int i, nvalues, nwrote, nleft, ncopied;
500 
501 	ei = &m->enuminfo;
502 
503 	nvalues = 0;
504 	nwrote = 0;
505 	nleft = sizeof(ei->strings);
506 	loc = ei->strings;
507 
508 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
509 		if ((1 << i) & v) {
510 			ei->strindex[nvalues] = nwrote;
511 			ncopied = strlcpy(loc, snd_mixernames[i], nleft) + 1;
512 			    /* strlcpy retval doesn't include terminator */
513 
514 			nwrote += ncopied;
515 			nleft -= ncopied;
516 			nvalues++;
517 
518 			/*
519 			 * XXX I don't think this should ever be possible.
520 			 * Even with a move to dynamic device/channel names,
521 			 * each label is limited to ~16 characters, so that'd
522 			 * take a LOT to fill this buffer.
523 			 */
524 			if ((nleft <= 0) || (nvalues >= OSS_ENUM_MAXVALUE)) {
525 				device_printf(m->dev,
526 				    "mix_setrecdevs:  Not enough room to store device names--please file a bug report.\n");
527 				device_printf(m->dev,
528 				    "mix_setrecdevs:  Please include details about your sound hardware, OS version, etc.\n");
529 				break;
530 			}
531 
532 			loc = &ei->strings[nwrote];
533 		}
534 	}
535 
536 	/*
537 	 * NB:	The SNDCTL_DSP_GET_RECSRC_NAMES ioctl ignores the dev
538 	 * 	and ctrl fields.
539 	 */
540 	ei->nvalues = nvalues;
541 	m->recdevs = v;
542 }
543 
544 void
545 mix_setparentchild(struct snd_mixer *m, u_int32_t parent, u_int32_t childs)
546 {
547 	u_int32_t mask = 0;
548 	int i;
549 
550 	if (m == NULL || parent >= SOUND_MIXER_NRDEVICES)
551 		return;
552 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
553 		if (i == parent)
554 			continue;
555 		if (childs & (1 << i)) {
556 			mask |= 1 << i;
557 			if (m->parent[i] < SOUND_MIXER_NRDEVICES)
558 				m->child[m->parent[i]] &= ~(1 << i);
559 			m->parent[i] = parent;
560 			m->child[i] = 0;
561 		}
562 	}
563 	mask &= ~(1 << parent);
564 	m->child[parent] = mask;
565 }
566 
567 void
568 mix_setrealdev(struct snd_mixer *m, u_int32_t dev, u_int32_t realdev)
569 {
570 	if (m == NULL || dev >= SOUND_MIXER_NRDEVICES ||
571 	    !(realdev == SOUND_MIXER_NONE || realdev < SOUND_MIXER_NRDEVICES))
572 		return;
573 	m->realdev[dev] = realdev;
574 }
575 
576 u_int32_t
577 mix_getparent(struct snd_mixer *m, u_int32_t dev)
578 {
579 	if (m == NULL || dev >= SOUND_MIXER_NRDEVICES)
580 		return SOUND_MIXER_NONE;
581 	return m->parent[dev];
582 }
583 
584 u_int32_t
585 mix_getchild(struct snd_mixer *m, u_int32_t dev)
586 {
587 	if (m == NULL || dev >= SOUND_MIXER_NRDEVICES)
588 		return 0;
589 	return m->child[dev];
590 }
591 
592 u_int32_t
593 mix_getdevs(struct snd_mixer *m)
594 {
595 	return m->devs;
596 }
597 
598 u_int32_t
599 mix_getrecdevs(struct snd_mixer *m)
600 {
601 	return m->recdevs;
602 }
603 
604 void *
605 mix_getdevinfo(struct snd_mixer *m)
606 {
607 	return m->devinfo;
608 }
609 
610 static struct snd_mixer *
611 mixer_obj_create(device_t dev, kobj_class_t cls, void *devinfo,
612     int type, const char *desc)
613 {
614 	struct snd_mixer *m;
615 	int i;
616 
617 	KASSERT(dev != NULL && cls != NULL && devinfo != NULL,
618 	    ("%s(): NULL data dev=%p cls=%p devinfo=%p",
619 	    __func__, dev, cls, devinfo));
620 	KASSERT(type == MIXER_TYPE_PRIMARY || type == MIXER_TYPE_SECONDARY,
621 	    ("invalid mixer type=%d", type));
622 
623 	m = (struct snd_mixer *)kobj_create(cls, M_MIXER, M_WAITOK | M_ZERO);
624 	snprintf(m->name, sizeof(m->name), "%s:mixer",
625 	    device_get_nameunit(dev));
626 	if (desc != NULL) {
627 		strlcat(m->name, ":", sizeof(m->name));
628 		strlcat(m->name, desc, sizeof(m->name));
629 	}
630 	m->lock = snd_mtxcreate(m->name, (type == MIXER_TYPE_PRIMARY) ?
631 	    "primary pcm mixer" : "secondary pcm mixer");
632 	m->type = type;
633 	m->devinfo = devinfo;
634 	m->busy = 0;
635 	m->dev = dev;
636 	for (i = 0; i < (sizeof(m->parent) / sizeof(m->parent[0])); i++) {
637 		m->parent[i] = SOUND_MIXER_NONE;
638 		m->child[i] = 0;
639 		m->realdev[i] = i;
640 	}
641 
642 	if (MIXER_INIT(m)) {
643 		snd_mtxlock(m->lock);
644 		snd_mtxfree(m->lock);
645 		kobj_delete((kobj_t)m, M_MIXER);
646 		return (NULL);
647 	}
648 
649 	return (m);
650 }
651 
652 int
653 mixer_delete(struct snd_mixer *m)
654 {
655 	KASSERT(m != NULL, ("NULL snd_mixer"));
656 	KASSERT(m->type == MIXER_TYPE_SECONDARY,
657 	    ("%s(): illegal mixer type=%d", __func__, m->type));
658 
659 	/* mixer uninit can sleep --hps */
660 
661 	MIXER_UNINIT(m);
662 
663 	snd_mtxfree(m->lock);
664 	kobj_delete((kobj_t)m, M_MIXER);
665 
666 	--mixer_count;
667 
668 	return (0);
669 }
670 
671 struct snd_mixer *
672 mixer_create(device_t dev, kobj_class_t cls, void *devinfo, const char *desc)
673 {
674 	struct snd_mixer *m;
675 
676 	m = mixer_obj_create(dev, cls, devinfo, MIXER_TYPE_SECONDARY, desc);
677 
678 	if (m != NULL)
679 		++mixer_count;
680 
681 	return (m);
682 }
683 
684 int
685 mixer_init(device_t dev, kobj_class_t cls, void *devinfo)
686 {
687 	struct snddev_info *snddev;
688 	struct snd_mixer *m;
689 	u_int16_t v;
690 	struct cdev *pdev;
691 	int i, unit, devunit, val;
692 
693 	snddev = device_get_softc(dev);
694 	if (snddev == NULL)
695 		return (-1);
696 
697 	if (resource_int_value(device_get_name(dev),
698 	    device_get_unit(dev), "eq", &val) == 0 && val != 0) {
699 		snddev->flags |= SD_F_EQ;
700 		if ((val & SD_F_EQ_MASK) == val)
701 			snddev->flags |= val;
702 		else
703 			snddev->flags |= SD_F_EQ_DEFAULT;
704 		snddev->eqpreamp = 0;
705 	}
706 
707 	m = mixer_obj_create(dev, cls, devinfo, MIXER_TYPE_PRIMARY, NULL);
708 	if (m == NULL)
709 		return (-1);
710 
711 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
712 		v = snd_mixerdefaults[i];
713 
714 		if (resource_int_value(device_get_name(dev),
715 		    device_get_unit(dev), snd_mixernames[i], &val) == 0) {
716 			if (val >= 0 && val <= 100) {
717 				v = (u_int16_t) val;
718 			}
719 		}
720 
721 		mixer_set(m, i, v | (v << 8));
722 	}
723 
724 	mixer_setrecsrc(m, 0); /* Set default input. */
725 
726 	unit = device_get_unit(dev);
727 	devunit = snd_mkunit(unit, SND_DEV_CTL, 0);
728 	pdev = make_dev(&mixer_cdevsw, PCMMINOR(devunit),
729 		 UID_ROOT, GID_WHEEL, 0666, "mixer%d", unit);
730 	pdev->si_drv1 = m;
731 	snddev->mixer_dev = pdev;
732 
733 	++mixer_count;
734 
735 	if (bootverbose) {
736 		for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
737 			if (!(m->devs & (1 << i)))
738 				continue;
739 			if (m->realdev[i] != i) {
740 				device_printf(dev, "Mixer \"%s\" -> \"%s\":",
741 				    snd_mixernames[i],
742 				    (m->realdev[i] < SOUND_MIXER_NRDEVICES) ?
743 				    snd_mixernames[m->realdev[i]] : "none");
744 			} else {
745 				device_printf(dev, "Mixer \"%s\":",
746 				    snd_mixernames[i]);
747 			}
748 			if (m->parent[i] < SOUND_MIXER_NRDEVICES)
749 				printf(" parent=\"%s\"",
750 				    snd_mixernames[m->parent[i]]);
751 			if (m->child[i] != 0)
752 				printf(" child=0x%08x", m->child[i]);
753 			printf("\n");
754 		}
755 		if (snddev->flags & SD_F_SOFTPCMVOL)
756 			device_printf(dev, "Soft PCM mixer ENABLED\n");
757 		if (snddev->flags & SD_F_EQ)
758 			device_printf(dev, "EQ Treble/Bass ENABLED\n");
759 	}
760 
761 	return (0);
762 }
763 
764 int
765 mixer_uninit(device_t dev)
766 {
767 	int i;
768 	struct snddev_info *d;
769 	struct snd_mixer *m;
770 	struct cdev *pdev;
771 
772 	d = device_get_softc(dev);
773 	pdev = mixer_get_devt(dev);
774 	if (d == NULL || pdev == NULL || pdev->si_drv1 == NULL)
775 		return EBADF;
776 
777 	m = pdev->si_drv1;
778 	KASSERT(m != NULL, ("NULL snd_mixer"));
779 	KASSERT(m->type == MIXER_TYPE_PRIMARY,
780 	    ("%s(): illegal mixer type=%d", __func__, m->type));
781 
782 	snd_mtxlock(m->lock);
783 
784 	if (m->busy) {
785 		snd_mtxunlock(m->lock);
786 		return EBUSY;
787 	}
788 
789 	/* destroy dev can sleep --hps */
790 
791 	snd_mtxunlock(m->lock);
792 
793 	pdev->si_drv1 = NULL;
794 	destroy_dev(pdev);
795 
796 	snd_mtxlock(m->lock);
797 
798 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++)
799 		mixer_set(m, i, 0);
800 
801 	mixer_setrecsrc(m, SOUND_MASK_MIC);
802 
803 	snd_mtxunlock(m->lock);
804 
805 	/* mixer uninit can sleep --hps */
806 
807 	MIXER_UNINIT(m);
808 
809 	snd_mtxfree(m->lock);
810 	kobj_delete((kobj_t)m, M_MIXER);
811 
812 	d->mixer_dev = NULL;
813 
814 	--mixer_count;
815 
816 	return 0;
817 }
818 
819 int
820 mixer_reinit(device_t dev)
821 {
822 	struct snd_mixer *m;
823 	struct cdev *pdev;
824 	int i;
825 
826 	pdev = mixer_get_devt(dev);
827 	m = pdev->si_drv1;
828 	snd_mtxlock(m->lock);
829 
830 	i = MIXER_REINIT(m);
831 	if (i) {
832 		snd_mtxunlock(m->lock);
833 		return i;
834 	}
835 
836 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++)
837 		mixer_set(m, i, m->level[i]);
838 
839 	mixer_setrecsrc(m, m->recsrc);
840 	snd_mtxunlock(m->lock);
841 
842 	return 0;
843 }
844 
845 static int
846 sysctl_hw_snd_hwvol_mixer(SYSCTL_HANDLER_ARGS)
847 {
848 	char devname[32];
849 	int error, dev;
850 	struct snd_mixer *m;
851 
852 	m = oidp->oid_arg1;
853 	snd_mtxlock(m->lock);
854 	strlcpy(devname, snd_mixernames[m->hwvol_mixer], sizeof(devname));
855 	snd_mtxunlock(m->lock);
856 	error = sysctl_handle_string(oidp, &devname[0], sizeof(devname), req);
857 	snd_mtxlock(m->lock);
858 	if (error == 0 && req->newptr != NULL) {
859 		dev = mixer_lookup(devname);
860 		if (dev == -1) {
861 			snd_mtxunlock(m->lock);
862 			return EINVAL;
863 		}
864 		else if (dev != m->hwvol_mixer) {
865 			m->hwvol_mixer = dev;
866 			m->hwvol_muted = 0;
867 		}
868 	}
869 	snd_mtxunlock(m->lock);
870 	return error;
871 }
872 
873 int
874 mixer_hwvol_init(device_t dev)
875 {
876 	struct snd_mixer *m;
877 	struct cdev *pdev;
878 
879 	pdev = mixer_get_devt(dev);
880 	m = pdev->si_drv1;
881 
882 	m->hwvol_mixer = SOUND_MIXER_VOLUME;
883 	m->hwvol_step = 5;
884 	SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
885 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
886             OID_AUTO, "hwvol_step", CTLFLAG_RWTUN, &m->hwvol_step, 0, "");
887 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
888 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
889             OID_AUTO, "hwvol_mixer", CTLTYPE_STRING | CTLFLAG_RWTUN, m, 0,
890 	    sysctl_hw_snd_hwvol_mixer, "A", "");
891 	return 0;
892 }
893 
894 void
895 mixer_hwvol_mute_locked(struct snd_mixer *m)
896 {
897 	if (m->hwvol_muted) {
898 		m->hwvol_muted = 0;
899 		mixer_set(m, m->hwvol_mixer, m->hwvol_mute_level);
900 	} else {
901 		m->hwvol_muted++;
902 		m->hwvol_mute_level = mixer_get(m, m->hwvol_mixer);
903 		mixer_set(m, m->hwvol_mixer, 0);
904 	}
905 }
906 
907 void
908 mixer_hwvol_mute(device_t dev)
909 {
910 	struct snd_mixer *m;
911 	struct cdev *pdev;
912 
913 	pdev = mixer_get_devt(dev);
914 	m = pdev->si_drv1;
915 	snd_mtxlock(m->lock);
916 	mixer_hwvol_mute_locked(m);
917 	snd_mtxunlock(m->lock);
918 }
919 
920 void
921 mixer_hwvol_step_locked(struct snd_mixer *m, int left_step, int right_step)
922 {
923 	int level, left, right;
924 
925 	if (m->hwvol_muted) {
926 		m->hwvol_muted = 0;
927 		level = m->hwvol_mute_level;
928 	} else
929 		level = mixer_get(m, m->hwvol_mixer);
930 	if (level != -1) {
931 		left = level & 0xff;
932 		right = (level >> 8) & 0xff;
933 		left += left_step * m->hwvol_step;
934 		if (left < 0)
935 			left = 0;
936 		else if (left > 100)
937 			left = 100;
938 		right += right_step * m->hwvol_step;
939 		if (right < 0)
940 			right = 0;
941 		else if (right > 100)
942 			right = 100;
943 		mixer_set(m, m->hwvol_mixer, left | right << 8);
944 	}
945 }
946 
947 void
948 mixer_hwvol_step(device_t dev, int left_step, int right_step)
949 {
950 	struct snd_mixer *m;
951 	struct cdev *pdev;
952 
953 	pdev = mixer_get_devt(dev);
954 	m = pdev->si_drv1;
955 	snd_mtxlock(m->lock);
956 	mixer_hwvol_step_locked(m, left_step, right_step);
957 	snd_mtxunlock(m->lock);
958 }
959 
960 int
961 mixer_busy(struct snd_mixer *m)
962 {
963 	KASSERT(m != NULL, ("NULL snd_mixer"));
964 
965 	return (m->busy);
966 }
967 
968 int
969 mix_set(struct snd_mixer *m, u_int dev, u_int left, u_int right)
970 {
971 	int ret;
972 
973 	KASSERT(m != NULL, ("NULL snd_mixer"));
974 
975 	snd_mtxlock(m->lock);
976 	ret = mixer_set(m, dev, left | (right << 8));
977 	snd_mtxunlock(m->lock);
978 
979 	return ((ret != 0) ? ENXIO : 0);
980 }
981 
982 int
983 mix_get(struct snd_mixer *m, u_int dev)
984 {
985 	int ret;
986 
987 	KASSERT(m != NULL, ("NULL snd_mixer"));
988 
989 	snd_mtxlock(m->lock);
990 	ret = mixer_get(m, dev);
991 	snd_mtxunlock(m->lock);
992 
993 	return (ret);
994 }
995 
996 int
997 mix_setrecsrc(struct snd_mixer *m, u_int32_t src)
998 {
999 	int ret;
1000 
1001 	KASSERT(m != NULL, ("NULL snd_mixer"));
1002 
1003 	snd_mtxlock(m->lock);
1004 	ret = mixer_setrecsrc(m, src);
1005 	snd_mtxunlock(m->lock);
1006 
1007 	return ((ret != 0) ? ENXIO : 0);
1008 }
1009 
1010 u_int32_t
1011 mix_getrecsrc(struct snd_mixer *m)
1012 {
1013 	u_int32_t ret;
1014 
1015 	KASSERT(m != NULL, ("NULL snd_mixer"));
1016 
1017 	snd_mtxlock(m->lock);
1018 	ret = mixer_getrecsrc(m);
1019 	snd_mtxunlock(m->lock);
1020 
1021 	return (ret);
1022 }
1023 
1024 int
1025 mix_get_type(struct snd_mixer *m)
1026 {
1027 	KASSERT(m != NULL, ("NULL snd_mixer"));
1028 
1029 	return (m->type);
1030 }
1031 
1032 /* ----------------------------------------------------------------------- */
1033 
1034 static int
1035 mixer_open(struct cdev *i_dev, int flags, int mode, struct thread *td)
1036 {
1037 	struct snddev_info *d;
1038 	struct snd_mixer *m;
1039 
1040 
1041 	if (i_dev == NULL || i_dev->si_drv1 == NULL)
1042 		return (EBADF);
1043 
1044 	m = i_dev->si_drv1;
1045 	d = device_get_softc(m->dev);
1046 	if (!PCM_REGISTERED(d))
1047 		return (EBADF);
1048 
1049 	/* XXX Need Giant magic entry ??? */
1050 
1051 	snd_mtxlock(m->lock);
1052 	m->busy = 1;
1053 	snd_mtxunlock(m->lock);
1054 
1055 	return (0);
1056 }
1057 
1058 static int
1059 mixer_close(struct cdev *i_dev, int flags, int mode, struct thread *td)
1060 {
1061 	struct snddev_info *d;
1062 	struct snd_mixer *m;
1063 	int ret;
1064 
1065 	if (i_dev == NULL || i_dev->si_drv1 == NULL)
1066 		return (EBADF);
1067 
1068 	m = i_dev->si_drv1;
1069 	d = device_get_softc(m->dev);
1070 	if (!PCM_REGISTERED(d))
1071 		return (EBADF);
1072 
1073 	/* XXX Need Giant magic entry ??? */
1074 
1075 	snd_mtxlock(m->lock);
1076 	ret = (m->busy == 0) ? EBADF : 0;
1077 	m->busy = 0;
1078 	snd_mtxunlock(m->lock);
1079 
1080 	return (ret);
1081 }
1082 
1083 static int
1084 mixer_ioctl_channel(struct cdev *dev, u_long cmd, caddr_t arg, int mode,
1085     struct thread *td, int from)
1086 {
1087 	struct snddev_info *d;
1088 	struct snd_mixer *m;
1089 	struct pcm_channel *c, *rdch, *wrch;
1090 	pid_t pid;
1091 	int j, ret;
1092 
1093 	if (td == NULL || td->td_proc == NULL)
1094 		return (-1);
1095 
1096 	m = dev->si_drv1;
1097 	d = device_get_softc(m->dev);
1098 	j = cmd & 0xff;
1099 
1100 	switch (j) {
1101 	case SOUND_MIXER_PCM:
1102 	case SOUND_MIXER_RECLEV:
1103 	case SOUND_MIXER_DEVMASK:
1104 	case SOUND_MIXER_CAPS:
1105 	case SOUND_MIXER_STEREODEVS:
1106 		break;
1107 	default:
1108 		return (-1);
1109 		break;
1110 	}
1111 
1112 	pid = td->td_proc->p_pid;
1113 	rdch = NULL;
1114 	wrch = NULL;
1115 	c = NULL;
1116 	ret = -1;
1117 
1118 	/*
1119 	 * This is unfair. Imagine single proc opening multiple
1120 	 * instances of same direction. What we do right now
1121 	 * is looking for the first matching proc/pid, and just
1122 	 * that. Nothing more. Consider it done.
1123 	 *
1124 	 * The better approach of controlling specific channel
1125 	 * pcm or rec volume is by doing mixer ioctl
1126 	 * (SNDCTL_DSP_[SET|GET][PLAY|REC]VOL / SOUND_MIXER_[PCM|RECLEV]
1127 	 * on its open fd, rather than cracky mixer bypassing here.
1128 	 */
1129 	CHN_FOREACH(c, d, channels.pcm.opened) {
1130 		CHN_LOCK(c);
1131 		if (c->pid != pid ||
1132 		    !(c->feederflags & (1 << FEEDER_VOLUME))) {
1133 			CHN_UNLOCK(c);
1134 			continue;
1135 		}
1136 		if (rdch == NULL && c->direction == PCMDIR_REC) {
1137 			rdch = c;
1138 			if (j == SOUND_MIXER_RECLEV)
1139 				goto mixer_ioctl_channel_proc;
1140 		} else if (wrch == NULL && c->direction == PCMDIR_PLAY) {
1141 			wrch = c;
1142 			if (j == SOUND_MIXER_PCM)
1143 				goto mixer_ioctl_channel_proc;
1144 		}
1145 		CHN_UNLOCK(c);
1146 		if (rdch != NULL && wrch != NULL)
1147 			break;
1148 	}
1149 
1150 	if (rdch == NULL && wrch == NULL)
1151 		return (-1);
1152 
1153 	if ((j == SOUND_MIXER_DEVMASK || j == SOUND_MIXER_CAPS ||
1154 	    j == SOUND_MIXER_STEREODEVS) &&
1155 	    (cmd & ~0xff) == MIXER_READ(0)) {
1156 		snd_mtxlock(m->lock);
1157 		*(int *)arg = mix_getdevs(m);
1158 		snd_mtxunlock(m->lock);
1159 		if (rdch != NULL)
1160 			*(int *)arg |= SOUND_MASK_RECLEV;
1161 		if (wrch != NULL)
1162 			*(int *)arg |= SOUND_MASK_PCM;
1163 		ret = 0;
1164 	}
1165 
1166 	return (ret);
1167 
1168 mixer_ioctl_channel_proc:
1169 
1170 	KASSERT(c != NULL, ("%s(): NULL channel", __func__));
1171 	CHN_LOCKASSERT(c);
1172 
1173 	if ((cmd & ~0xff) == MIXER_WRITE(0)) {
1174 		int left, right, center;
1175 
1176 		left = *(int *)arg & 0x7f;
1177 		right = (*(int *)arg >> 8) & 0x7f;
1178 		center = (left + right) >> 1;
1179 		chn_setvolume_multi(c, SND_VOL_C_PCM, left, right, center);
1180 	} else if ((cmd & ~0xff) == MIXER_READ(0)) {
1181 		*(int *)arg = CHN_GETVOLUME(c, SND_VOL_C_PCM, SND_CHN_T_FL);
1182 		*(int *)arg |=
1183 		    CHN_GETVOLUME(c, SND_VOL_C_PCM, SND_CHN_T_FR) << 8;
1184 	}
1185 
1186 	CHN_UNLOCK(c);
1187 
1188 	return (0);
1189 }
1190 
1191 static int
1192 mixer_ioctl(struct cdev *i_dev, u_long cmd, caddr_t arg, int mode,
1193     struct thread *td)
1194 {
1195 	struct snddev_info *d;
1196 	int ret;
1197 
1198 	if (i_dev == NULL || i_dev->si_drv1 == NULL)
1199 		return (EBADF);
1200 
1201 	d = device_get_softc(((struct snd_mixer *)i_dev->si_drv1)->dev);
1202 	if (!PCM_REGISTERED(d))
1203 		return (EBADF);
1204 
1205 	PCM_GIANT_ENTER(d);
1206 	PCM_ACQUIRE_QUICK(d);
1207 
1208 	ret = -1;
1209 
1210 	if (mixer_bypass != 0 && (d->flags & SD_F_VPC))
1211 		ret = mixer_ioctl_channel(i_dev, cmd, arg, mode, td,
1212 		    MIXER_CMD_CDEV);
1213 
1214 	if (ret == -1)
1215 		ret = mixer_ioctl_cmd(i_dev, cmd, arg, mode, td,
1216 		    MIXER_CMD_CDEV);
1217 
1218 	PCM_RELEASE_QUICK(d);
1219 	PCM_GIANT_LEAVE(d);
1220 
1221 	return (ret);
1222 }
1223 
1224 static void
1225 mixer_mixerinfo(struct snd_mixer *m, mixer_info *mi)
1226 {
1227 	bzero((void *)mi, sizeof(*mi));
1228 	strlcpy(mi->id, m->name, sizeof(mi->id));
1229 	strlcpy(mi->name, device_get_desc(m->dev), sizeof(mi->name));
1230 	mi->modify_counter = m->modify_counter;
1231 }
1232 
1233 /*
1234  * XXX Make sure you can guarantee concurrency safety before calling this
1235  *     function, be it through Giant, PCM_*, etc !
1236  */
1237 int
1238 mixer_ioctl_cmd(struct cdev *i_dev, u_long cmd, caddr_t arg, int mode,
1239     struct thread *td, int from)
1240 {
1241 	struct snd_mixer *m;
1242 	int ret = EINVAL, *arg_i = (int *)arg;
1243 	int v = -1, j = cmd & 0xff;
1244 
1245 	/*
1246 	 * Certain ioctls may be made on any type of device (audio, mixer,
1247 	 * and MIDI).  Handle those special cases here.
1248 	 */
1249 	if (IOCGROUP(cmd) == 'X') {
1250 		switch (cmd) {
1251 		case SNDCTL_SYSINFO:
1252 			sound_oss_sysinfo((oss_sysinfo *)arg);
1253 			return (0);
1254 		case SNDCTL_CARDINFO:
1255 			return (sound_oss_card_info((oss_card_info *)arg));
1256 	    	case SNDCTL_AUDIOINFO:
1257 	    	case SNDCTL_AUDIOINFO_EX:
1258 	    	case SNDCTL_ENGINEINFO:
1259 			return (dsp_oss_audioinfo(i_dev, (oss_audioinfo *)arg));
1260 		case SNDCTL_MIXERINFO:
1261 			return (mixer_oss_mixerinfo(i_dev, (oss_mixerinfo *)arg));
1262 		}
1263 		return (EINVAL);
1264 	}
1265 
1266 	m = i_dev->si_drv1;
1267 
1268 	if (m == NULL)
1269 		return (EBADF);
1270 
1271 	snd_mtxlock(m->lock);
1272 	if (from == MIXER_CMD_CDEV && !m->busy) {
1273 		snd_mtxunlock(m->lock);
1274 		return (EBADF);
1275 	}
1276 	switch (cmd) {
1277 	case SNDCTL_DSP_GET_RECSRC_NAMES:
1278 		bcopy((void *)&m->enuminfo, arg, sizeof(oss_mixer_enuminfo));
1279 		ret = 0;
1280 		goto done;
1281 	case SNDCTL_DSP_GET_RECSRC:
1282 		ret = mixer_get_recroute(m, arg_i);
1283 		goto done;
1284 	case SNDCTL_DSP_SET_RECSRC:
1285 		ret = mixer_set_recroute(m, *arg_i);
1286 		goto done;
1287 	case OSS_GETVERSION:
1288 		*arg_i = SOUND_VERSION;
1289 		ret = 0;
1290 		goto done;
1291 	case SOUND_MIXER_INFO:
1292 		mixer_mixerinfo(m, (mixer_info *)arg);
1293 		ret = 0;
1294 		goto done;
1295 	}
1296 	if ((cmd & ~0xff) == MIXER_WRITE(0)) {
1297 		if (j == SOUND_MIXER_RECSRC)
1298 			ret = mixer_setrecsrc(m, *arg_i);
1299 		else
1300 			ret = mixer_set(m, j, *arg_i);
1301 		snd_mtxunlock(m->lock);
1302 		return ((ret == 0) ? 0 : ENXIO);
1303 	}
1304 	if ((cmd & ~0xff) == MIXER_READ(0)) {
1305 		switch (j) {
1306 		case SOUND_MIXER_DEVMASK:
1307 		case SOUND_MIXER_CAPS:
1308 		case SOUND_MIXER_STEREODEVS:
1309 			v = mix_getdevs(m);
1310 			break;
1311 		case SOUND_MIXER_RECMASK:
1312 			v = mix_getrecdevs(m);
1313 			break;
1314 		case SOUND_MIXER_RECSRC:
1315 			v = mixer_getrecsrc(m);
1316 			break;
1317 		default:
1318 			v = mixer_get(m, j);
1319 		}
1320 		*arg_i = v;
1321 		snd_mtxunlock(m->lock);
1322 		return ((v != -1) ? 0 : ENXIO);
1323 	}
1324 done:
1325 	snd_mtxunlock(m->lock);
1326 	return (ret);
1327 }
1328 
1329 static void
1330 mixer_clone(void *arg,
1331     struct ucred *cred,
1332     char *name, int namelen, struct cdev **dev)
1333 {
1334 	struct snddev_info *d;
1335 
1336 	if (*dev != NULL)
1337 		return;
1338 	if (strcmp(name, "mixer") == 0) {
1339 		d = devclass_get_softc(pcm_devclass, snd_unit);
1340 		if (PCM_REGISTERED(d) && d->mixer_dev != NULL) {
1341 			*dev = d->mixer_dev;
1342 			dev_ref(*dev);
1343 		}
1344 	}
1345 }
1346 
1347 static void
1348 mixer_sysinit(void *p)
1349 {
1350 	if (mixer_ehtag != NULL)
1351 		return;
1352 	mixer_ehtag = EVENTHANDLER_REGISTER(dev_clone, mixer_clone, 0, 1000);
1353 }
1354 
1355 static void
1356 mixer_sysuninit(void *p)
1357 {
1358 	if (mixer_ehtag == NULL)
1359 		return;
1360 	EVENTHANDLER_DEREGISTER(dev_clone, mixer_ehtag);
1361 	mixer_ehtag = NULL;
1362 }
1363 
1364 SYSINIT(mixer_sysinit, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, mixer_sysinit, NULL);
1365 SYSUNINIT(mixer_sysuninit, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, mixer_sysuninit, NULL);
1366 
1367 /**
1368  * @brief Handler for SNDCTL_MIXERINFO
1369  *
1370  * This function searches for a mixer based on the numeric ID stored
1371  * in oss_miserinfo::dev.  If set to -1, then information about the
1372  * current mixer handling the request is provided.  Note, however, that
1373  * this ioctl may be made with any sound device (audio, mixer, midi).
1374  *
1375  * @note Caller must not hold any PCM device, channel, or mixer locks.
1376  *
1377  * See http://manuals.opensound.com/developer/SNDCTL_MIXERINFO.html for
1378  * more information.
1379  *
1380  * @param i_dev	character device on which the ioctl arrived
1381  * @param arg	user argument (oss_mixerinfo *)
1382  *
1383  * @retval EINVAL	oss_mixerinfo::dev specified a bad value
1384  * @retval 0		success
1385  */
1386 int
1387 mixer_oss_mixerinfo(struct cdev *i_dev, oss_mixerinfo *mi)
1388 {
1389 	struct snddev_info *d;
1390 	struct snd_mixer *m;
1391 	int nmix, i;
1392 
1393 	/*
1394 	 * If probing the device handling the ioctl, make sure it's a mixer
1395 	 * device.  (This ioctl is valid on audio, mixer, and midi devices.)
1396 	 */
1397 	if (mi->dev == -1 && i_dev->si_devsw != &mixer_cdevsw)
1398 		return (EINVAL);
1399 
1400 	d = NULL;
1401 	m = NULL;
1402 	nmix = 0;
1403 
1404 	/*
1405 	 * There's a 1:1 relationship between mixers and PCM devices, so
1406 	 * begin by iterating over PCM devices and search for our mixer.
1407 	 */
1408 	for (i = 0; pcm_devclass != NULL &&
1409 	    i < devclass_get_maxunit(pcm_devclass); i++) {
1410 		d = devclass_get_softc(pcm_devclass, i);
1411 		if (!PCM_REGISTERED(d))
1412 			continue;
1413 
1414 		/* XXX Need Giant magic entry */
1415 
1416 		/* See the note in function docblock. */
1417 		PCM_UNLOCKASSERT(d);
1418 		PCM_LOCK(d);
1419 
1420 		if (d->mixer_dev != NULL && d->mixer_dev->si_drv1 != NULL &&
1421 		    ((mi->dev == -1 && d->mixer_dev == i_dev) ||
1422 		    mi->dev == nmix)) {
1423 			m = d->mixer_dev->si_drv1;
1424 			mtx_lock(m->lock);
1425 
1426 			/*
1427 			 * At this point, the following synchronization stuff
1428 			 * has happened:
1429 			 * - a specific PCM device is locked.
1430 			 * - a specific mixer device has been locked, so be
1431 			 *   sure to unlock when existing.
1432 			 */
1433 			bzero((void *)mi, sizeof(*mi));
1434 			mi->dev = nmix;
1435 			snprintf(mi->id, sizeof(mi->id), "mixer%d", i);
1436 			strlcpy(mi->name, m->name, sizeof(mi->name));
1437 			mi->modify_counter = m->modify_counter;
1438 			mi->card_number = i;
1439 			/*
1440 			 * Currently, FreeBSD assumes 1:1 relationship between
1441 			 * a pcm and mixer devices, so this is hardcoded to 0.
1442 			 */
1443 			mi->port_number = 0;
1444 
1445 			/**
1446 			 * @todo Fill in @sa oss_mixerinfo::mixerhandle.
1447 			 * @note From 4Front:  "mixerhandle is an arbitrary
1448 			 *       string that identifies the mixer better than
1449 			 *       the device number (mixerinfo.dev).  Device
1450 			 *       numbers may change depending on the order the
1451 			 *       drivers are loaded. However the handle should
1452 			 *       remain the same provided that the sound card
1453 			 *       is not moved to another PCI slot."
1454 			 */
1455 
1456 			/**
1457 			 * @note
1458 			 * @sa oss_mixerinfo::magic is a reserved field.
1459 			 *
1460 			 * @par
1461 			 * From 4Front:  "magic is usually 0. However some
1462 			 * devices may have dedicated setup utilities and the
1463 			 * magic field may contain an unique driver specific
1464 			 * value (managed by [4Front])."
1465 			 */
1466 
1467 			mi->enabled = device_is_attached(m->dev) ? 1 : 0;
1468 			/**
1469 			 * The only flag for @sa oss_mixerinfo::caps is
1470 			 * currently MIXER_CAP_VIRTUAL, which I'm not sure we
1471 			 * really worry about.
1472 			 */
1473 			/**
1474 			 * Mixer extensions currently aren't supported, so
1475 			 * leave @sa oss_mixerinfo::nrext blank for now.
1476 			 */
1477 			/**
1478 			 * @todo Fill in @sa oss_mixerinfo::priority (requires
1479 			 *       touching drivers?)
1480 			 * @note The priority field is for mixer applets to
1481 			 * determine which mixer should be the default, with 0
1482 			 * being least preferred and 10 being most preferred.
1483 			 * From 4Front:  "OSS drivers like ICH use higher
1484 			 * values (10) because such chips are known to be used
1485 			 * only on motherboards.  Drivers for high end pro
1486 			 * devices use 0 because they will never be the
1487 			 * default mixer. Other devices use values 1 to 9
1488 			 * depending on the estimated probability of being the
1489 			 * default device.
1490 			 *
1491 			 * XXX Described by Hannu@4Front, but not found in
1492 			 *     soundcard.h.
1493 			strlcpy(mi->devnode, devtoname(d->mixer_dev),
1494 			sizeof(mi->devnode));
1495 			mi->legacy_device = i;
1496 			 */
1497 			mtx_unlock(m->lock);
1498 		} else
1499 			++nmix;
1500 
1501 		PCM_UNLOCK(d);
1502 
1503 		if (m != NULL)
1504 			return (0);
1505 	}
1506 
1507 	return (EINVAL);
1508 }
1509 
1510 /*
1511  * Allow the sound driver to use the mixer lock to protect its mixer
1512  * data:
1513  */
1514 struct mtx *
1515 mixer_get_lock(struct snd_mixer *m)
1516 {
1517 	if (m->lock == NULL) {
1518 		return (&Giant);
1519 	}
1520 	return (m->lock);
1521 }
1522 
1523 int
1524 mix_get_locked(struct snd_mixer *m, u_int dev, int *pleft, int *pright)
1525 {
1526 	int level;
1527 
1528 	level = mixer_get(m, dev);
1529 	if (level < 0) {
1530 		*pright = *pleft = -1;
1531 		return (-1);
1532 	}
1533 
1534 	*pleft = level & 0xFF;
1535 	*pright = (level >> 8) & 0xFF;
1536 
1537 	return (0);
1538 }
1539 
1540 int
1541 mix_set_locked(struct snd_mixer *m, u_int dev, int left, int right)
1542 {
1543 	int level;
1544 
1545 	level = (left & 0xFF) | ((right & 0xFF) << 8);
1546 
1547 	return (mixer_set(m, dev, level));
1548 }
1549