xref: /freebsd/sys/dev/sound/pcm/dsp.c (revision ab40f58ccfe6c07ebefddc72f4661a52fe746353)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2005-2009 Ariff Abdullah <ariff@FreeBSD.org>
5  * Portions Copyright (c) Ryan Beasley <ryan.beasley@gmail.com> - GSoC 2006
6  * Copyright (c) 1999 Cameron Grant <cg@FreeBSD.org>
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #ifdef HAVE_KERNEL_OPTION_HEADERS
32 #include "opt_snd.h"
33 #endif
34 
35 #include <dev/sound/pcm/sound.h>
36 #include <sys/ctype.h>
37 #include <sys/lock.h>
38 #include <sys/rwlock.h>
39 #include <sys/sysent.h>
40 
41 #include <vm/vm.h>
42 #include <vm/vm_object.h>
43 #include <vm/vm_page.h>
44 #include <vm/vm_pager.h>
45 
46 SND_DECLARE_FILE("$FreeBSD$");
47 
48 static int dsp_mmap_allow_prot_exec = 0;
49 SYSCTL_INT(_hw_snd, OID_AUTO, compat_linux_mmap, CTLFLAG_RWTUN,
50     &dsp_mmap_allow_prot_exec, 0,
51     "linux mmap compatibility (-1=force disable 0=auto 1=force enable)");
52 
53 static int dsp_basename_clone = 1;
54 SYSCTL_INT(_hw_snd, OID_AUTO, basename_clone, CTLFLAG_RWTUN,
55     &dsp_basename_clone, 0,
56     "DSP basename cloning (0: Disable; 1: Enabled)");
57 
58 struct dsp_cdevinfo {
59 	struct pcm_channel *rdch, *wrch;
60 	struct pcm_channel *volch;
61 	int busy, simplex;
62 	TAILQ_ENTRY(dsp_cdevinfo) link;
63 };
64 
65 #define PCM_RDCH(x)		(((struct dsp_cdevinfo *)(x)->si_drv1)->rdch)
66 #define PCM_WRCH(x)		(((struct dsp_cdevinfo *)(x)->si_drv1)->wrch)
67 #define PCM_VOLCH(x)		(((struct dsp_cdevinfo *)(x)->si_drv1)->volch)
68 #define PCM_SIMPLEX(x)		(((struct dsp_cdevinfo *)(x)->si_drv1)->simplex)
69 
70 #define DSP_CDEVINFO_CACHESIZE	8
71 
72 #define DSP_REGISTERED(x, y)	(PCM_REGISTERED(x) &&			\
73 				 (y) != NULL && (y)->si_drv1 != NULL)
74 
75 #define OLDPCM_IOCTL
76 
77 static d_open_t dsp_open;
78 static d_close_t dsp_close;
79 static d_read_t dsp_read;
80 static d_write_t dsp_write;
81 static d_ioctl_t dsp_ioctl;
82 static d_poll_t dsp_poll;
83 static d_mmap_t dsp_mmap;
84 static d_mmap_single_t dsp_mmap_single;
85 
86 struct cdevsw dsp_cdevsw = {
87 	.d_version =	D_VERSION,
88 	.d_open =	dsp_open,
89 	.d_close =	dsp_close,
90 	.d_read =	dsp_read,
91 	.d_write =	dsp_write,
92 	.d_ioctl =	dsp_ioctl,
93 	.d_poll =	dsp_poll,
94 	.d_mmap =	dsp_mmap,
95 	.d_mmap_single = dsp_mmap_single,
96 	.d_name =	"dsp",
97 };
98 
99 static eventhandler_tag dsp_ehtag = NULL;
100 static int dsp_umax = -1;
101 static int dsp_cmax = -1;
102 
103 static int dsp_oss_syncgroup(struct pcm_channel *wrch, struct pcm_channel *rdch, oss_syncgroup *group);
104 static int dsp_oss_syncstart(int sg_id);
105 static int dsp_oss_policy(struct pcm_channel *wrch, struct pcm_channel *rdch, int policy);
106 static int dsp_oss_cookedmode(struct pcm_channel *wrch, struct pcm_channel *rdch, int enabled);
107 static int dsp_oss_getchnorder(struct pcm_channel *wrch, struct pcm_channel *rdch, unsigned long long *map);
108 static int dsp_oss_setchnorder(struct pcm_channel *wrch, struct pcm_channel *rdch, unsigned long long *map);
109 static int dsp_oss_getchannelmask(struct pcm_channel *wrch, struct pcm_channel *rdch, int *mask);
110 #ifdef OSSV4_EXPERIMENT
111 static int dsp_oss_getlabel(struct pcm_channel *wrch, struct pcm_channel *rdch, oss_label_t *label);
112 static int dsp_oss_setlabel(struct pcm_channel *wrch, struct pcm_channel *rdch, oss_label_t *label);
113 static int dsp_oss_getsong(struct pcm_channel *wrch, struct pcm_channel *rdch, oss_longname_t *song);
114 static int dsp_oss_setsong(struct pcm_channel *wrch, struct pcm_channel *rdch, oss_longname_t *song);
115 static int dsp_oss_setname(struct pcm_channel *wrch, struct pcm_channel *rdch, oss_longname_t *name);
116 #endif
117 
118 static struct snddev_info *
119 dsp_get_info(struct cdev *dev)
120 {
121 	return (devclass_get_softc(pcm_devclass, PCMUNIT(dev)));
122 }
123 
124 static uint32_t
125 dsp_get_flags(struct cdev *dev)
126 {
127 	device_t bdev;
128 
129 	bdev = devclass_get_device(pcm_devclass, PCMUNIT(dev));
130 
131 	return ((bdev != NULL) ? pcm_getflags(bdev) : 0xffffffff);
132 }
133 
134 static void
135 dsp_set_flags(struct cdev *dev, uint32_t flags)
136 {
137 	device_t bdev;
138 
139 	bdev = devclass_get_device(pcm_devclass, PCMUNIT(dev));
140 
141 	if (bdev != NULL)
142 		pcm_setflags(bdev, flags);
143 }
144 
145 /*
146  * return the channels associated with an open device instance.
147  * lock channels specified.
148  */
149 static int
150 getchns(struct cdev *dev, struct pcm_channel **rdch, struct pcm_channel **wrch,
151     uint32_t prio)
152 {
153 	struct snddev_info *d;
154 	struct pcm_channel *ch;
155 	uint32_t flags;
156 
157 	if (PCM_SIMPLEX(dev) != 0) {
158 		d = dsp_get_info(dev);
159 		if (!PCM_REGISTERED(d))
160 			return (ENXIO);
161 		PCM_LOCK(d);
162 		PCM_WAIT(d);
163 		PCM_ACQUIRE(d);
164 		/*
165 		 * Note: order is important -
166 		 *       pcm flags -> prio query flags -> wild guess
167 		 */
168 		ch = NULL;
169 		flags = dsp_get_flags(dev);
170 		if (flags & SD_F_PRIO_WR) {
171 			ch = PCM_RDCH(dev);
172 			PCM_RDCH(dev) = NULL;
173 		} else if (flags & SD_F_PRIO_RD) {
174 			ch = PCM_WRCH(dev);
175 			PCM_WRCH(dev) = NULL;
176 		} else if (prio & SD_F_PRIO_WR) {
177 			ch = PCM_RDCH(dev);
178 			PCM_RDCH(dev) = NULL;
179 			flags |= SD_F_PRIO_WR;
180 		} else if (prio & SD_F_PRIO_RD) {
181 			ch = PCM_WRCH(dev);
182 			PCM_WRCH(dev) = NULL;
183 			flags |= SD_F_PRIO_RD;
184 		} else if (PCM_WRCH(dev) != NULL) {
185 			ch = PCM_RDCH(dev);
186 			PCM_RDCH(dev) = NULL;
187 			flags |= SD_F_PRIO_WR;
188 		} else if (PCM_RDCH(dev) != NULL) {
189 			ch = PCM_WRCH(dev);
190 			PCM_WRCH(dev) = NULL;
191 			flags |= SD_F_PRIO_RD;
192 		}
193 		PCM_SIMPLEX(dev) = 0;
194 		dsp_set_flags(dev, flags);
195 		if (ch != NULL) {
196 			CHN_LOCK(ch);
197 			pcm_chnref(ch, -1);
198 			pcm_chnrelease(ch);
199 		}
200 		PCM_RELEASE(d);
201 		PCM_UNLOCK(d);
202 	}
203 
204 	*rdch = PCM_RDCH(dev);
205 	*wrch = PCM_WRCH(dev);
206 
207 	if (*rdch != NULL && (prio & SD_F_PRIO_RD))
208 		CHN_LOCK(*rdch);
209 	if (*wrch != NULL && (prio & SD_F_PRIO_WR))
210 		CHN_LOCK(*wrch);
211 
212 	return (0);
213 }
214 
215 /* unlock specified channels */
216 static void
217 relchns(struct cdev *dev, struct pcm_channel *rdch, struct pcm_channel *wrch,
218     uint32_t prio)
219 {
220 	if (wrch != NULL && (prio & SD_F_PRIO_WR))
221 		CHN_UNLOCK(wrch);
222 	if (rdch != NULL && (prio & SD_F_PRIO_RD))
223 		CHN_UNLOCK(rdch);
224 }
225 
226 static void
227 dsp_cdevinfo_alloc(struct cdev *dev,
228     struct pcm_channel *rdch, struct pcm_channel *wrch,
229     struct pcm_channel *volch)
230 {
231 	struct snddev_info *d;
232 	struct dsp_cdevinfo *cdi;
233 	int simplex;
234 
235 	d = dsp_get_info(dev);
236 
237 	KASSERT(PCM_REGISTERED(d) && dev != NULL && dev->si_drv1 == NULL &&
238 	    ((rdch == NULL && wrch == NULL) || rdch != wrch),
239 	    ("bogus %s(), what are you trying to accomplish here?", __func__));
240 	PCM_BUSYASSERT(d);
241 	PCM_LOCKASSERT(d);
242 
243 	simplex = (dsp_get_flags(dev) & SD_F_SIMPLEX) ? 1 : 0;
244 
245 	/*
246 	 * Scan for free instance entry and put it into the end of list.
247 	 * Create new one if necessary.
248 	 */
249 	TAILQ_FOREACH(cdi, &d->dsp_cdevinfo_pool, link) {
250 		if (cdi->busy != 0)
251 			break;
252 		cdi->rdch = rdch;
253 		cdi->wrch = wrch;
254 		cdi->volch = volch;
255 		cdi->simplex = simplex;
256 		cdi->busy = 1;
257 		TAILQ_REMOVE(&d->dsp_cdevinfo_pool, cdi, link);
258 		TAILQ_INSERT_TAIL(&d->dsp_cdevinfo_pool, cdi, link);
259 		dev->si_drv1 = cdi;
260 		return;
261 	}
262 	PCM_UNLOCK(d);
263 	cdi = malloc(sizeof(*cdi), M_DEVBUF, M_WAITOK | M_ZERO);
264 	PCM_LOCK(d);
265 	cdi->rdch = rdch;
266 	cdi->wrch = wrch;
267 	cdi->volch = volch;
268 	cdi->simplex = simplex;
269 	cdi->busy = 1;
270 	TAILQ_INSERT_TAIL(&d->dsp_cdevinfo_pool, cdi, link);
271 	dev->si_drv1 = cdi;
272 }
273 
274 static void
275 dsp_cdevinfo_free(struct cdev *dev)
276 {
277 	struct snddev_info *d;
278 	struct dsp_cdevinfo *cdi, *tmp;
279 	uint32_t flags;
280 	int i;
281 
282 	d = dsp_get_info(dev);
283 
284 	KASSERT(PCM_REGISTERED(d) && dev != NULL && dev->si_drv1 != NULL &&
285 	    PCM_RDCH(dev) == NULL && PCM_WRCH(dev) == NULL &&
286 	    PCM_VOLCH(dev) == NULL,
287 	    ("bogus %s(), what are you trying to accomplish here?", __func__));
288 	PCM_BUSYASSERT(d);
289 	PCM_LOCKASSERT(d);
290 
291 	cdi = dev->si_drv1;
292 	dev->si_drv1 = NULL;
293 	cdi->rdch = NULL;
294 	cdi->wrch = NULL;
295 	cdi->volch = NULL;
296 	cdi->simplex = 0;
297 	cdi->busy = 0;
298 
299 	/*
300 	 * Once it is free, move it back to the beginning of list for
301 	 * faster new entry allocation.
302 	 */
303 	TAILQ_REMOVE(&d->dsp_cdevinfo_pool, cdi, link);
304 	TAILQ_INSERT_HEAD(&d->dsp_cdevinfo_pool, cdi, link);
305 
306 	/*
307 	 * Scan the list, cache free entries up to DSP_CDEVINFO_CACHESIZE.
308 	 * Reset simplex flags.
309 	 */
310 	flags = dsp_get_flags(dev) & ~SD_F_PRIO_SET;
311 	i = DSP_CDEVINFO_CACHESIZE;
312 	TAILQ_FOREACH_SAFE(cdi, &d->dsp_cdevinfo_pool, link, tmp) {
313 		if (cdi->busy != 0) {
314 			if (cdi->simplex == 0) {
315 				if (cdi->rdch != NULL)
316 					flags |= SD_F_PRIO_RD;
317 				if (cdi->wrch != NULL)
318 					flags |= SD_F_PRIO_WR;
319 			}
320 		} else {
321 			if (i == 0) {
322 				TAILQ_REMOVE(&d->dsp_cdevinfo_pool, cdi, link);
323 				free(cdi, M_DEVBUF);
324 			} else
325 				i--;
326 		}
327 	}
328 	dsp_set_flags(dev, flags);
329 }
330 
331 void
332 dsp_cdevinfo_init(struct snddev_info *d)
333 {
334 	struct dsp_cdevinfo *cdi;
335 	int i;
336 
337 	KASSERT(d != NULL, ("NULL snddev_info"));
338 	PCM_BUSYASSERT(d);
339 	PCM_UNLOCKASSERT(d);
340 
341 	TAILQ_INIT(&d->dsp_cdevinfo_pool);
342 	for (i = 0; i < DSP_CDEVINFO_CACHESIZE; i++) {
343 		cdi = malloc(sizeof(*cdi), M_DEVBUF, M_WAITOK | M_ZERO);
344 		TAILQ_INSERT_HEAD(&d->dsp_cdevinfo_pool, cdi, link);
345 	}
346 }
347 
348 void
349 dsp_cdevinfo_flush(struct snddev_info *d)
350 {
351 	struct dsp_cdevinfo *cdi, *tmp;
352 
353 	KASSERT(d != NULL, ("NULL snddev_info"));
354 	PCM_BUSYASSERT(d);
355 	PCM_UNLOCKASSERT(d);
356 
357 	cdi = TAILQ_FIRST(&d->dsp_cdevinfo_pool);
358 	while (cdi != NULL) {
359 		tmp = TAILQ_NEXT(cdi, link);
360 		free(cdi, M_DEVBUF);
361 		cdi = tmp;
362 	}
363 	TAILQ_INIT(&d->dsp_cdevinfo_pool);
364 }
365 
366 /* duplex / simplex cdev type */
367 enum {
368 	DSP_CDEV_TYPE_RDONLY,		/* simplex read-only (record)   */
369 	DSP_CDEV_TYPE_WRONLY,		/* simplex write-only (play)    */
370 	DSP_CDEV_TYPE_RDWR		/* duplex read, write, or both  */
371 };
372 
373 enum {
374 	DSP_CDEV_VOLCTL_NONE,
375 	DSP_CDEV_VOLCTL_READ,
376 	DSP_CDEV_VOLCTL_WRITE
377 };
378 
379 #define DSP_F_VALID(x)		((x) & (FREAD | FWRITE))
380 #define DSP_F_DUPLEX(x)		(((x) & (FREAD | FWRITE)) == (FREAD | FWRITE))
381 #define DSP_F_SIMPLEX(x)	(!DSP_F_DUPLEX(x))
382 #define DSP_F_READ(x)		((x) & FREAD)
383 #define DSP_F_WRITE(x)		((x) & FWRITE)
384 
385 static const struct {
386 	int type;
387 	char *name;
388 	char *sep;
389 	char *alias;
390 	int use_sep;
391 	int hw;
392 	int max;
393 	int volctl;
394 	uint32_t fmt, spd;
395 	int query;
396 } dsp_cdevs[] = {
397 	{ SND_DEV_DSP,         "dsp",    ".", NULL, 0, 0, 0, 0,
398 	  SND_FORMAT(AFMT_U8, 1, 0),     DSP_DEFAULT_SPEED,
399 	  DSP_CDEV_TYPE_RDWR },
400 	{ SND_DEV_AUDIO,       "audio",  ".", NULL, 0, 0, 0, 0,
401 	  SND_FORMAT(AFMT_MU_LAW, 1, 0), DSP_DEFAULT_SPEED,
402 	  DSP_CDEV_TYPE_RDWR },
403 	{ SND_DEV_DSP16,       "dspW",   ".", NULL, 0, 0, 0, 0,
404 	  SND_FORMAT(AFMT_S16_LE, 1, 0), DSP_DEFAULT_SPEED,
405 	  DSP_CDEV_TYPE_RDWR },
406 	{ SND_DEV_DSPHW_PLAY,  "dsp",   ".p", NULL, 1, 1, SND_MAXHWCHAN, 1,
407 	  SND_FORMAT(AFMT_S16_LE, 2, 0), 48000, DSP_CDEV_TYPE_WRONLY },
408 	{ SND_DEV_DSPHW_VPLAY, "dsp",  ".vp", NULL, 1, 1, SND_MAXVCHANS, 1,
409 	  SND_FORMAT(AFMT_S16_LE, 2, 0), 48000, DSP_CDEV_TYPE_WRONLY },
410 	{ SND_DEV_DSPHW_REC,   "dsp",   ".r", NULL, 1, 1, SND_MAXHWCHAN, 1,
411 	  SND_FORMAT(AFMT_S16_LE, 2, 0), 48000, DSP_CDEV_TYPE_RDONLY },
412 	{ SND_DEV_DSPHW_VREC,  "dsp",  ".vr", NULL, 1, 1, SND_MAXVCHANS, 1,
413 	  SND_FORMAT(AFMT_S16_LE, 2, 0), 48000, DSP_CDEV_TYPE_RDONLY },
414 	{ SND_DEV_DSPHW_CD,    "dspcd",  ".", NULL, 0, 0, 0, 0,
415 	  SND_FORMAT(AFMT_S16_LE, 2, 0), 44100, DSP_CDEV_TYPE_RDWR   },
416 	/* Low priority, OSSv4 aliases. */
417 	{ SND_DEV_DSP,      "dsp_ac3",   ".", "dsp", 0, 0, 0, 0,
418 	  SND_FORMAT(AFMT_U8, 1, 0),     DSP_DEFAULT_SPEED,
419 	  DSP_CDEV_TYPE_RDWR },
420 	{ SND_DEV_DSP,     "dsp_mmap",   ".", "dsp", 0, 0, 0, 0,
421 	  SND_FORMAT(AFMT_U8, 1, 0),     DSP_DEFAULT_SPEED,
422 	  DSP_CDEV_TYPE_RDWR },
423 	{ SND_DEV_DSP,  "dsp_multich",   ".", "dsp", 0, 0, 0, 0,
424 	  SND_FORMAT(AFMT_U8, 1, 0),     DSP_DEFAULT_SPEED,
425 	  DSP_CDEV_TYPE_RDWR },
426 	{ SND_DEV_DSP, "dsp_spdifout",   ".", "dsp", 0, 0, 0, 0,
427 	  SND_FORMAT(AFMT_U8, 1, 0),     DSP_DEFAULT_SPEED,
428 	  DSP_CDEV_TYPE_RDWR },
429 	{ SND_DEV_DSP,  "dsp_spdifin",   ".", "dsp", 0, 0, 0, 0,
430 	  SND_FORMAT(AFMT_U8, 1, 0),     DSP_DEFAULT_SPEED,
431 	  DSP_CDEV_TYPE_RDWR },
432 };
433 
434 #define DSP_FIXUP_ERROR()		do {				\
435 	prio = dsp_get_flags(i_dev);					\
436 	if (!DSP_F_VALID(flags))					\
437 		error = EINVAL;						\
438 	if (!DSP_F_DUPLEX(flags) &&					\
439 	    ((DSP_F_READ(flags) && d->reccount == 0) ||			\
440 	    (DSP_F_WRITE(flags) && d->playcount == 0)))			\
441 		error = ENOTSUP;					\
442 	else if (!DSP_F_DUPLEX(flags) && (prio & SD_F_SIMPLEX) &&	\
443 	    ((DSP_F_READ(flags) && (prio & SD_F_PRIO_WR)) ||		\
444 	    (DSP_F_WRITE(flags) && (prio & SD_F_PRIO_RD))))		\
445 		error = EBUSY;						\
446 	else if (DSP_REGISTERED(d, i_dev))				\
447 		error = EBUSY;						\
448 } while (0)
449 
450 static int
451 dsp_open(struct cdev *i_dev, int flags, int mode, struct thread *td)
452 {
453 	struct pcm_channel *rdch, *wrch;
454 	struct snddev_info *d;
455 	uint32_t fmt, spd, prio, volctl;
456 	int i, error, rderror, wrerror, devtype, wdevunit, rdevunit;
457 
458 	/* Kind of impossible.. */
459 	if (i_dev == NULL || td == NULL)
460 		return (ENODEV);
461 
462 	d = dsp_get_info(i_dev);
463 	if (!PCM_REGISTERED(d))
464 		return (EBADF);
465 
466 	PCM_GIANT_ENTER(d);
467 
468 	/* Lock snddev so nobody else can monkey with it. */
469 	PCM_LOCK(d);
470 	PCM_WAIT(d);
471 
472 	/*
473 	 * Try to acquire cloned device before someone else pick it.
474 	 * ENODEV means this is not a cloned droids.
475 	 */
476 	error = snd_clone_acquire(i_dev);
477 	if (!(error == 0 || error == ENODEV)) {
478 		DSP_FIXUP_ERROR();
479 		PCM_UNLOCK(d);
480 		PCM_GIANT_EXIT(d);
481 		return (error);
482 	}
483 
484 	error = 0;
485 	DSP_FIXUP_ERROR();
486 
487 	if (error != 0) {
488 		(void)snd_clone_release(i_dev);
489 		PCM_UNLOCK(d);
490 		PCM_GIANT_EXIT(d);
491 		return (error);
492 	}
493 
494 	/*
495 	 * That is just enough. Acquire and unlock pcm lock so
496 	 * the other will just have to wait until we finish doing
497 	 * everything.
498 	 */
499 	PCM_ACQUIRE(d);
500 	PCM_UNLOCK(d);
501 
502 	devtype = PCMDEV(i_dev);
503 	wdevunit = -1;
504 	rdevunit = -1;
505 	fmt = 0;
506 	spd = 0;
507 	volctl = DSP_CDEV_VOLCTL_NONE;
508 
509 	for (i = 0; i < (sizeof(dsp_cdevs) / sizeof(dsp_cdevs[0])); i++) {
510 		if (devtype != dsp_cdevs[i].type || dsp_cdevs[i].alias != NULL)
511 			continue;
512 		/*
513 		 * Volume control only valid for DSPHW devices,
514 		 * and it must be opened in opposite direction be it
515 		 * simplex or duplex. Anything else will be handled
516 		 * as usual.
517 		 */
518 		if (dsp_cdevs[i].query == DSP_CDEV_TYPE_WRONLY) {
519 			if (dsp_cdevs[i].volctl != 0 &&
520 			    DSP_F_READ(flags)) {
521 				volctl = DSP_CDEV_VOLCTL_WRITE;
522 				flags &= ~FREAD;
523 				flags |= FWRITE;
524 			}
525 			if (DSP_F_READ(flags)) {
526 				(void)snd_clone_release(i_dev);
527 				PCM_RELEASE_QUICK(d);
528 				PCM_GIANT_EXIT(d);
529 				return (ENOTSUP);
530 			}
531 			wdevunit = dev2unit(i_dev);
532 		} else if (dsp_cdevs[i].query == DSP_CDEV_TYPE_RDONLY) {
533 			if (dsp_cdevs[i].volctl != 0 &&
534 			    DSP_F_WRITE(flags)) {
535 				volctl = DSP_CDEV_VOLCTL_READ;
536 				flags &= ~FWRITE;
537 				flags |= FREAD;
538 			}
539 			if (DSP_F_WRITE(flags)) {
540 				(void)snd_clone_release(i_dev);
541 				PCM_RELEASE_QUICK(d);
542 				PCM_GIANT_EXIT(d);
543 				return (ENOTSUP);
544 			}
545 			rdevunit = dev2unit(i_dev);
546 		}
547 		fmt = dsp_cdevs[i].fmt;
548 		spd = dsp_cdevs[i].spd;
549 		break;
550 	}
551 
552 	/* No matching devtype? */
553 	if (fmt == 0 || spd == 0)
554 		panic("impossible devtype %d", devtype);
555 
556 	rdch = NULL;
557 	wrch = NULL;
558 	rderror = 0;
559 	wrerror = 0;
560 
561 	/*
562 	 * if we get here, the open request is valid- either:
563 	 *   * we were previously not open
564 	 *   * we were open for play xor record and the opener wants
565 	 *     the non-open direction
566 	 */
567 	if (DSP_F_READ(flags)) {
568 		/* open for read */
569 		rderror = pcm_chnalloc(d, &rdch, PCMDIR_REC,
570 		    td->td_proc->p_pid, td->td_proc->p_comm, rdevunit);
571 
572 		if (rderror == 0 && chn_reset(rdch, fmt, spd) != 0)
573 			rderror = ENXIO;
574 
575 		if (volctl == DSP_CDEV_VOLCTL_READ)
576 			rderror = 0;
577 
578 		if (rderror != 0) {
579 			if (rdch != NULL)
580 				pcm_chnrelease(rdch);
581 			if (!DSP_F_DUPLEX(flags)) {
582 				(void)snd_clone_release(i_dev);
583 				PCM_RELEASE_QUICK(d);
584 				PCM_GIANT_EXIT(d);
585 				return (rderror);
586 			}
587 			rdch = NULL;
588 		} else if (volctl == DSP_CDEV_VOLCTL_READ) {
589 			if (rdch != NULL) {
590 				pcm_chnref(rdch, 1);
591 				pcm_chnrelease(rdch);
592 			}
593 		} else {
594 			if (flags & O_NONBLOCK)
595 				rdch->flags |= CHN_F_NBIO;
596 			if (flags & O_EXCL)
597 				rdch->flags |= CHN_F_EXCLUSIVE;
598 			pcm_chnref(rdch, 1);
599 			if (volctl == DSP_CDEV_VOLCTL_NONE)
600 				chn_vpc_reset(rdch, SND_VOL_C_PCM, 0);
601 		 	CHN_UNLOCK(rdch);
602 		}
603 	}
604 
605 	if (DSP_F_WRITE(flags)) {
606 		/* open for write */
607 		wrerror = pcm_chnalloc(d, &wrch, PCMDIR_PLAY,
608 		    td->td_proc->p_pid, td->td_proc->p_comm, wdevunit);
609 
610 		if (wrerror == 0 && chn_reset(wrch, fmt, spd) != 0)
611 			wrerror = ENXIO;
612 
613 		if (volctl == DSP_CDEV_VOLCTL_WRITE)
614 			wrerror = 0;
615 
616 		if (wrerror != 0) {
617 			if (wrch != NULL)
618 				pcm_chnrelease(wrch);
619 			if (!DSP_F_DUPLEX(flags)) {
620 				if (rdch != NULL) {
621 					/*
622 					 * Lock, deref and release previously
623 					 * created record channel
624 					 */
625 					CHN_LOCK(rdch);
626 					pcm_chnref(rdch, -1);
627 					pcm_chnrelease(rdch);
628 				}
629 				(void)snd_clone_release(i_dev);
630 				PCM_RELEASE_QUICK(d);
631 				PCM_GIANT_EXIT(d);
632 				return (wrerror);
633 			}
634 			wrch = NULL;
635 		} else if (volctl == DSP_CDEV_VOLCTL_WRITE) {
636 			if (wrch != NULL) {
637 				pcm_chnref(wrch, 1);
638 				pcm_chnrelease(wrch);
639 			}
640 		} else {
641 			if (flags & O_NONBLOCK)
642 				wrch->flags |= CHN_F_NBIO;
643 			if (flags & O_EXCL)
644 				wrch->flags |= CHN_F_EXCLUSIVE;
645 			pcm_chnref(wrch, 1);
646 			if (volctl == DSP_CDEV_VOLCTL_NONE)
647 				chn_vpc_reset(wrch, SND_VOL_C_PCM, 0);
648 			CHN_UNLOCK(wrch);
649 		}
650 	}
651 
652 
653 	PCM_LOCK(d);
654 
655 	/*
656 	 * We're done. Allocate channels information for this cdev.
657 	 */
658 	switch (volctl) {
659 	case DSP_CDEV_VOLCTL_READ:
660 		KASSERT(wrch == NULL, ("wrch=%p not null!", wrch));
661 		dsp_cdevinfo_alloc(i_dev, NULL, NULL, rdch);
662 		break;
663 	case DSP_CDEV_VOLCTL_WRITE:
664 		KASSERT(rdch == NULL, ("rdch=%p not null!", rdch));
665 		dsp_cdevinfo_alloc(i_dev, NULL, NULL, wrch);
666 		break;
667 	case DSP_CDEV_VOLCTL_NONE:
668 	default:
669 		if (wrch == NULL && rdch == NULL) {
670 			(void)snd_clone_release(i_dev);
671 			PCM_RELEASE(d);
672 			PCM_UNLOCK(d);
673 			PCM_GIANT_EXIT(d);
674 			if (wrerror != 0)
675 				return (wrerror);
676 			if (rderror != 0)
677 				return (rderror);
678 			return (EINVAL);
679 		}
680 		dsp_cdevinfo_alloc(i_dev, rdch, wrch, NULL);
681 		if (rdch != NULL)
682 			CHN_INSERT_HEAD(d, rdch, channels.pcm.opened);
683 		if (wrch != NULL)
684 			CHN_INSERT_HEAD(d, wrch, channels.pcm.opened);
685 		break;
686 	}
687 
688 	/*
689 	 * Increase clone refcount for its automatic garbage collector.
690 	 */
691 	(void)snd_clone_ref(i_dev);
692 
693 	PCM_RELEASE(d);
694 	PCM_UNLOCK(d);
695 
696 	PCM_GIANT_LEAVE(d);
697 
698 	return (0);
699 }
700 
701 static int
702 dsp_close(struct cdev *i_dev, int flags, int mode, struct thread *td)
703 {
704 	struct pcm_channel *rdch, *wrch, *volch;
705 	struct snddev_info *d;
706 	int sg_ids, rdref, wdref;
707 
708 	d = dsp_get_info(i_dev);
709 	if (!DSP_REGISTERED(d, i_dev))
710 		return (EBADF);
711 
712 	PCM_GIANT_ENTER(d);
713 
714 	PCM_LOCK(d);
715 	PCM_WAIT(d);
716 	PCM_ACQUIRE(d);
717 
718 	rdch = PCM_RDCH(i_dev);
719 	wrch = PCM_WRCH(i_dev);
720 	volch = PCM_VOLCH(i_dev);
721 
722 	PCM_RDCH(i_dev) = NULL;
723 	PCM_WRCH(i_dev) = NULL;
724 	PCM_VOLCH(i_dev) = NULL;
725 
726 	rdref = -1;
727 	wdref = -1;
728 
729 	if (volch != NULL) {
730 		if (volch == rdch)
731 			rdref--;
732 		else if (volch == wrch)
733 			wdref--;
734 		else {
735 			CHN_LOCK(volch);
736 			pcm_chnref(volch, -1);
737 			CHN_UNLOCK(volch);
738 		}
739 	}
740 
741 	if (rdch != NULL)
742 		CHN_REMOVE(d, rdch, channels.pcm.opened);
743 	if (wrch != NULL)
744 		CHN_REMOVE(d, wrch, channels.pcm.opened);
745 
746 	if (rdch != NULL || wrch != NULL) {
747 		PCM_UNLOCK(d);
748 		if (rdch != NULL) {
749 			/*
750 			 * The channel itself need not be locked because:
751 			 *   a)  Adding a channel to a syncgroup happens only
752 			 *       in dsp_ioctl(), which cannot run concurrently
753 			 *       to dsp_close().
754 			 *   b)  The syncmember pointer (sm) is protected by
755 			 *       the global syncgroup list lock.
756 			 *   c)  A channel can't just disappear, invalidating
757 			 *       pointers, unless it's closed/dereferenced
758 			 *       first.
759 			 */
760 			PCM_SG_LOCK();
761 			sg_ids = chn_syncdestroy(rdch);
762 			PCM_SG_UNLOCK();
763 			if (sg_ids != 0)
764 				free_unr(pcmsg_unrhdr, sg_ids);
765 
766 			CHN_LOCK(rdch);
767 			pcm_chnref(rdch, rdref);
768 			chn_abort(rdch); /* won't sleep */
769 			rdch->flags &= ~(CHN_F_RUNNING | CHN_F_MMAP |
770 			    CHN_F_DEAD | CHN_F_EXCLUSIVE);
771 			chn_reset(rdch, 0, 0);
772 			pcm_chnrelease(rdch);
773 		}
774 		if (wrch != NULL) {
775 			/*
776 			 * Please see block above.
777 			 */
778 			PCM_SG_LOCK();
779 			sg_ids = chn_syncdestroy(wrch);
780 			PCM_SG_UNLOCK();
781 			if (sg_ids != 0)
782 				free_unr(pcmsg_unrhdr, sg_ids);
783 
784 			CHN_LOCK(wrch);
785 			pcm_chnref(wrch, wdref);
786 			chn_flush(wrch); /* may sleep */
787 			wrch->flags &= ~(CHN_F_RUNNING | CHN_F_MMAP |
788 			    CHN_F_DEAD | CHN_F_EXCLUSIVE);
789 			chn_reset(wrch, 0, 0);
790 			pcm_chnrelease(wrch);
791 		}
792 		PCM_LOCK(d);
793 	}
794 
795 	dsp_cdevinfo_free(i_dev);
796 	/*
797 	 * Release clone busy state and unref it so the automatic
798 	 * garbage collector will get the hint and do the remaining
799 	 * cleanup process.
800 	 */
801 	(void)snd_clone_release(i_dev);
802 
803 	/*
804 	 * destroy_dev() might sleep, so release pcm lock
805 	 * here and rely on pcm cv serialization.
806 	 */
807 	PCM_UNLOCK(d);
808 	(void)snd_clone_unref(i_dev);
809 	PCM_LOCK(d);
810 
811 	PCM_RELEASE(d);
812 	PCM_UNLOCK(d);
813 
814 	PCM_GIANT_LEAVE(d);
815 
816 	return (0);
817 }
818 
819 static __inline int
820 dsp_io_ops(struct cdev *i_dev, struct uio *buf)
821 {
822 	struct snddev_info *d;
823 	struct pcm_channel **ch, *rdch, *wrch;
824 	int (*chn_io)(struct pcm_channel *, struct uio *);
825 	int prio, ret;
826 	pid_t runpid;
827 
828 	KASSERT(i_dev != NULL && buf != NULL &&
829 	    (buf->uio_rw == UIO_READ || buf->uio_rw == UIO_WRITE),
830 	    ("%s(): io train wreck!", __func__));
831 
832 	d = dsp_get_info(i_dev);
833 	if (!DSP_REGISTERED(d, i_dev))
834 		return (EBADF);
835 
836 	PCM_GIANT_ENTER(d);
837 
838 	switch (buf->uio_rw) {
839 	case UIO_READ:
840 		prio = SD_F_PRIO_RD;
841 		ch = &rdch;
842 		chn_io = chn_read;
843 		break;
844 	case UIO_WRITE:
845 		prio = SD_F_PRIO_WR;
846 		ch = &wrch;
847 		chn_io = chn_write;
848 		break;
849 	default:
850 		panic("invalid/corrupted uio direction: %d", buf->uio_rw);
851 		break;
852 	}
853 
854 	rdch = NULL;
855 	wrch = NULL;
856 	runpid = buf->uio_td->td_proc->p_pid;
857 
858 	getchns(i_dev, &rdch, &wrch, prio);
859 
860 	if (*ch == NULL || !((*ch)->flags & CHN_F_BUSY)) {
861 		PCM_GIANT_EXIT(d);
862 		return (EBADF);
863 	}
864 
865 	if (((*ch)->flags & (CHN_F_MMAP | CHN_F_DEAD)) ||
866 	    (((*ch)->flags & CHN_F_RUNNING) && (*ch)->pid != runpid)) {
867 		relchns(i_dev, rdch, wrch, prio);
868 		PCM_GIANT_EXIT(d);
869 		return (EINVAL);
870 	} else if (!((*ch)->flags & CHN_F_RUNNING)) {
871 		(*ch)->flags |= CHN_F_RUNNING;
872 		(*ch)->pid = runpid;
873 	}
874 
875 	/*
876 	 * chn_read/write must give up channel lock in order to copy bytes
877 	 * from/to userland, so up the "in progress" counter to make sure
878 	 * someone else doesn't come along and muss up the buffer.
879 	 */
880 	++(*ch)->inprog;
881 	ret = chn_io(*ch, buf);
882 	--(*ch)->inprog;
883 
884 	CHN_BROADCAST(&(*ch)->cv);
885 
886 	relchns(i_dev, rdch, wrch, prio);
887 
888 	PCM_GIANT_LEAVE(d);
889 
890 	return (ret);
891 }
892 
893 static int
894 dsp_read(struct cdev *i_dev, struct uio *buf, int flag)
895 {
896 	return (dsp_io_ops(i_dev, buf));
897 }
898 
899 static int
900 dsp_write(struct cdev *i_dev, struct uio *buf, int flag)
901 {
902 	return (dsp_io_ops(i_dev, buf));
903 }
904 
905 static int
906 dsp_get_volume_channel(struct cdev *dev, struct pcm_channel **volch)
907 {
908 	struct snddev_info *d;
909 	struct pcm_channel *c;
910 	int unit;
911 
912 	KASSERT(dev != NULL && volch != NULL,
913 	    ("%s(): NULL query dev=%p volch=%p", __func__, dev, volch));
914 
915 	d = dsp_get_info(dev);
916 	if (!PCM_REGISTERED(d)) {
917 		*volch = NULL;
918 		return (EINVAL);
919 	}
920 
921 	PCM_UNLOCKASSERT(d);
922 
923 	*volch = NULL;
924 
925 	c = PCM_VOLCH(dev);
926 	if (c != NULL) {
927 		if (!(c->feederflags & (1 << FEEDER_VOLUME)))
928 			return (-1);
929 		*volch = c;
930 		return (0);
931 	}
932 
933 	PCM_LOCK(d);
934 	PCM_WAIT(d);
935 	PCM_ACQUIRE(d);
936 
937 	unit = dev2unit(dev);
938 
939 	CHN_FOREACH(c, d, channels.pcm) {
940 		CHN_LOCK(c);
941 		if (c->unit != unit) {
942 			CHN_UNLOCK(c);
943 			continue;
944 		}
945 		*volch = c;
946 		pcm_chnref(c, 1);
947 		PCM_VOLCH(dev) = c;
948 		CHN_UNLOCK(c);
949 		PCM_RELEASE(d);
950 		PCM_UNLOCK(d);
951 		return ((c->feederflags & (1 << FEEDER_VOLUME)) ? 0 : -1);
952 	}
953 
954 	PCM_RELEASE(d);
955 	PCM_UNLOCK(d);
956 
957 	return (EINVAL);
958 }
959 
960 static int
961 dsp_ioctl_channel(struct cdev *dev, struct pcm_channel *volch, u_long cmd,
962     caddr_t arg)
963 {
964 	struct snddev_info *d;
965 	struct pcm_channel *rdch, *wrch;
966 	int j, devtype, ret;
967 
968 	d = dsp_get_info(dev);
969 	if (!PCM_REGISTERED(d) || !(dsp_get_flags(dev) & SD_F_VPC))
970 		return (-1);
971 
972 	PCM_UNLOCKASSERT(d);
973 
974 	j = cmd & 0xff;
975 
976 	rdch = PCM_RDCH(dev);
977 	wrch = PCM_WRCH(dev);
978 
979 	/* No specific channel, look into cache */
980 	if (volch == NULL)
981 		volch = PCM_VOLCH(dev);
982 
983 	/* Look harder */
984 	if (volch == NULL) {
985 		if (j == SOUND_MIXER_RECLEV && rdch != NULL)
986 			volch = rdch;
987 		else if (j == SOUND_MIXER_PCM && wrch != NULL)
988 			volch = wrch;
989 	}
990 
991 	devtype = PCMDEV(dev);
992 
993 	/* Look super harder */
994 	if (volch == NULL &&
995 	    (devtype == SND_DEV_DSPHW_PLAY || devtype == SND_DEV_DSPHW_VPLAY ||
996 	    devtype == SND_DEV_DSPHW_REC || devtype == SND_DEV_DSPHW_VREC)) {
997 		ret = dsp_get_volume_channel(dev, &volch);
998 		if (ret != 0)
999 			return (ret);
1000 		if (volch == NULL)
1001 			return (EINVAL);
1002 	}
1003 
1004 	/* Final validation */
1005 	if (volch != NULL) {
1006 		CHN_LOCK(volch);
1007 		if (!(volch->feederflags & (1 << FEEDER_VOLUME))) {
1008 			CHN_UNLOCK(volch);
1009 			return (-1);
1010 		}
1011 		if (volch->direction == PCMDIR_PLAY)
1012 			wrch = volch;
1013 		else
1014 			rdch = volch;
1015 	}
1016 
1017 	ret = EINVAL;
1018 
1019 	if (volch != NULL &&
1020 	    ((j == SOUND_MIXER_PCM && volch->direction == PCMDIR_PLAY) ||
1021 	    (j == SOUND_MIXER_RECLEV && volch->direction == PCMDIR_REC))) {
1022 		if ((cmd & ~0xff) == MIXER_WRITE(0)) {
1023 			int left, right, center;
1024 
1025 			left = *(int *)arg & 0x7f;
1026 			right = ((*(int *)arg) >> 8) & 0x7f;
1027 			center = (left + right) >> 1;
1028 			chn_setvolume_multi(volch, SND_VOL_C_PCM, left, right,
1029 			    center);
1030 		} else if ((cmd & ~0xff) == MIXER_READ(0)) {
1031 			*(int *)arg = CHN_GETVOLUME(volch,
1032 				SND_VOL_C_PCM, SND_CHN_T_FL);
1033 			*(int *)arg |= CHN_GETVOLUME(volch,
1034 				SND_VOL_C_PCM, SND_CHN_T_FR) << 8;
1035 		}
1036 		ret = 0;
1037 	} else if (rdch != NULL || wrch != NULL) {
1038 		switch (j) {
1039 		case SOUND_MIXER_DEVMASK:
1040 		case SOUND_MIXER_CAPS:
1041 		case SOUND_MIXER_STEREODEVS:
1042 			if ((cmd & ~0xff) == MIXER_READ(0)) {
1043 				*(int *)arg = 0;
1044 				if (rdch != NULL)
1045 					*(int *)arg |= SOUND_MASK_RECLEV;
1046 				if (wrch != NULL)
1047 					*(int *)arg |= SOUND_MASK_PCM;
1048 			}
1049 			ret = 0;
1050 			break;
1051 		case SOUND_MIXER_RECMASK:
1052 		case SOUND_MIXER_RECSRC:
1053 			if ((cmd & ~0xff) == MIXER_READ(0))
1054 				*(int *)arg = 0;
1055 			ret = 0;
1056 			break;
1057 		default:
1058 			break;
1059 		}
1060 	}
1061 
1062 	if (volch != NULL)
1063 		CHN_UNLOCK(volch);
1064 
1065 	return (ret);
1066 }
1067 
1068 static int
1069 dsp_ioctl(struct cdev *i_dev, u_long cmd, caddr_t arg, int mode,
1070     struct thread *td)
1071 {
1072     	struct pcm_channel *chn, *rdch, *wrch;
1073 	struct snddev_info *d;
1074 	u_long xcmd;
1075 	int *arg_i, ret, tmp;
1076 
1077 	d = dsp_get_info(i_dev);
1078 	if (!DSP_REGISTERED(d, i_dev))
1079 		return (EBADF);
1080 
1081 	PCM_GIANT_ENTER(d);
1082 
1083 	arg_i = (int *)arg;
1084 	ret = 0;
1085 	xcmd = 0;
1086 	chn = NULL;
1087 
1088 	if (IOCGROUP(cmd) == 'M') {
1089 		if (cmd == OSS_GETVERSION) {
1090 			*arg_i = SOUND_VERSION;
1091 			PCM_GIANT_EXIT(d);
1092 			return (0);
1093 		}
1094 		ret = dsp_ioctl_channel(i_dev, PCM_VOLCH(i_dev), cmd, arg);
1095 		if (ret != -1) {
1096 			PCM_GIANT_EXIT(d);
1097 			return (ret);
1098 		}
1099 
1100 		if (d->mixer_dev != NULL) {
1101 			PCM_ACQUIRE_QUICK(d);
1102 			ret = mixer_ioctl_cmd(d->mixer_dev, cmd, arg, -1, td,
1103 			    MIXER_CMD_DIRECT);
1104 			PCM_RELEASE_QUICK(d);
1105 		} else
1106 			ret = EBADF;
1107 
1108 		PCM_GIANT_EXIT(d);
1109 
1110 		return (ret);
1111 	}
1112 
1113 	/*
1114 	 * Certain ioctls may be made on any type of device (audio, mixer,
1115 	 * and MIDI).  Handle those special cases here.
1116 	 */
1117 	if (IOCGROUP(cmd) == 'X') {
1118 		PCM_ACQUIRE_QUICK(d);
1119 		switch(cmd) {
1120 		case SNDCTL_SYSINFO:
1121 			sound_oss_sysinfo((oss_sysinfo *)arg);
1122 			break;
1123 		case SNDCTL_CARDINFO:
1124 			ret = sound_oss_card_info((oss_card_info *)arg);
1125 			break;
1126 		case SNDCTL_AUDIOINFO:
1127 		case SNDCTL_AUDIOINFO_EX:
1128 		case SNDCTL_ENGINEINFO:
1129 			ret = dsp_oss_audioinfo(i_dev, (oss_audioinfo *)arg);
1130 			break;
1131 		case SNDCTL_MIXERINFO:
1132 			ret = mixer_oss_mixerinfo(i_dev, (oss_mixerinfo *)arg);
1133 			break;
1134 		default:
1135 			ret = EINVAL;
1136 		}
1137 		PCM_RELEASE_QUICK(d);
1138 		PCM_GIANT_EXIT(d);
1139 		return (ret);
1140 	}
1141 
1142 	getchns(i_dev, &rdch, &wrch, 0);
1143 
1144 	if (wrch != NULL && (wrch->flags & CHN_F_DEAD))
1145 		wrch = NULL;
1146 	if (rdch != NULL && (rdch->flags & CHN_F_DEAD))
1147 		rdch = NULL;
1148 
1149 	if (wrch == NULL && rdch == NULL) {
1150 		PCM_GIANT_EXIT(d);
1151 		return (EINVAL);
1152 	}
1153 
1154     	switch(cmd) {
1155 #ifdef OLDPCM_IOCTL
1156     	/*
1157      	 * we start with the new ioctl interface.
1158      	 */
1159     	case AIONWRITE:	/* how many bytes can write ? */
1160 		if (wrch) {
1161 			CHN_LOCK(wrch);
1162 /*
1163 		if (wrch && wrch->bufhard.dl)
1164 			while (chn_wrfeed(wrch) == 0);
1165 */
1166 			*arg_i = sndbuf_getfree(wrch->bufsoft);
1167 			CHN_UNLOCK(wrch);
1168 		} else {
1169 			*arg_i = 0;
1170 			ret = EINVAL;
1171 		}
1172 		break;
1173 
1174     	case AIOSSIZE:     /* set the current blocksize */
1175 		{
1176 	    		struct snd_size *p = (struct snd_size *)arg;
1177 
1178 			p->play_size = 0;
1179 			p->rec_size = 0;
1180 			PCM_ACQUIRE_QUICK(d);
1181 	    		if (wrch) {
1182 				CHN_LOCK(wrch);
1183 				chn_setblocksize(wrch, 2, p->play_size);
1184 				p->play_size = sndbuf_getblksz(wrch->bufsoft);
1185 				CHN_UNLOCK(wrch);
1186 			}
1187 	    		if (rdch) {
1188 				CHN_LOCK(rdch);
1189 				chn_setblocksize(rdch, 2, p->rec_size);
1190 				p->rec_size = sndbuf_getblksz(rdch->bufsoft);
1191 				CHN_UNLOCK(rdch);
1192 			}
1193 			PCM_RELEASE_QUICK(d);
1194 		}
1195 		break;
1196     	case AIOGSIZE:	/* get the current blocksize */
1197 		{
1198 	    		struct snd_size *p = (struct snd_size *)arg;
1199 
1200 	    		if (wrch) {
1201 				CHN_LOCK(wrch);
1202 				p->play_size = sndbuf_getblksz(wrch->bufsoft);
1203 				CHN_UNLOCK(wrch);
1204 			}
1205 	    		if (rdch) {
1206 				CHN_LOCK(rdch);
1207 				p->rec_size = sndbuf_getblksz(rdch->bufsoft);
1208 				CHN_UNLOCK(rdch);
1209 			}
1210 		}
1211 		break;
1212 
1213     	case AIOSFMT:
1214     	case AIOGFMT:
1215 		{
1216 	    		snd_chan_param *p = (snd_chan_param *)arg;
1217 
1218 			if (cmd == AIOSFMT &&
1219 			    ((p->play_format != 0 && p->play_rate == 0) ||
1220 			    (p->rec_format != 0 && p->rec_rate == 0))) {
1221 				ret = EINVAL;
1222 				break;
1223 			}
1224 			PCM_ACQUIRE_QUICK(d);
1225 	    		if (wrch) {
1226 				CHN_LOCK(wrch);
1227 				if (cmd == AIOSFMT && p->play_format != 0) {
1228 					chn_setformat(wrch,
1229 					    SND_FORMAT(p->play_format,
1230 					    AFMT_CHANNEL(wrch->format),
1231 					    AFMT_EXTCHANNEL(wrch->format)));
1232 					chn_setspeed(wrch, p->play_rate);
1233 				}
1234 	    			p->play_rate = wrch->speed;
1235 	    			p->play_format = AFMT_ENCODING(wrch->format);
1236 				CHN_UNLOCK(wrch);
1237 			} else {
1238 	    			p->play_rate = 0;
1239 	    			p->play_format = 0;
1240 	    		}
1241 	    		if (rdch) {
1242 				CHN_LOCK(rdch);
1243 				if (cmd == AIOSFMT && p->rec_format != 0) {
1244 					chn_setformat(rdch,
1245 					    SND_FORMAT(p->rec_format,
1246 					    AFMT_CHANNEL(rdch->format),
1247 					    AFMT_EXTCHANNEL(rdch->format)));
1248 					chn_setspeed(rdch, p->rec_rate);
1249 				}
1250 				p->rec_rate = rdch->speed;
1251 				p->rec_format = AFMT_ENCODING(rdch->format);
1252 				CHN_UNLOCK(rdch);
1253 			} else {
1254 	    			p->rec_rate = 0;
1255 	    			p->rec_format = 0;
1256 	    		}
1257 			PCM_RELEASE_QUICK(d);
1258 		}
1259 		break;
1260 
1261     	case AIOGCAP:     /* get capabilities */
1262 		{
1263 	    		snd_capabilities *p = (snd_capabilities *)arg;
1264 			struct pcmchan_caps *pcaps = NULL, *rcaps = NULL;
1265 			struct cdev *pdev;
1266 
1267 			PCM_LOCK(d);
1268 			if (rdch) {
1269 				CHN_LOCK(rdch);
1270 				rcaps = chn_getcaps(rdch);
1271 			}
1272 			if (wrch) {
1273 				CHN_LOCK(wrch);
1274 				pcaps = chn_getcaps(wrch);
1275 			}
1276 	    		p->rate_min = max(rcaps? rcaps->minspeed : 0,
1277 	                      		  pcaps? pcaps->minspeed : 0);
1278 	    		p->rate_max = min(rcaps? rcaps->maxspeed : 1000000,
1279 	                      		  pcaps? pcaps->maxspeed : 1000000);
1280 	    		p->bufsize = min(rdch? sndbuf_getsize(rdch->bufsoft) : 1000000,
1281 	                     		 wrch? sndbuf_getsize(wrch->bufsoft) : 1000000);
1282 			/* XXX bad on sb16 */
1283 	    		p->formats = (rdch? chn_getformats(rdch) : 0xffffffff) &
1284 			 	     (wrch? chn_getformats(wrch) : 0xffffffff);
1285 			if (rdch && wrch)
1286 				p->formats |= (dsp_get_flags(i_dev) & SD_F_SIMPLEX)? 0 : AFMT_FULLDUPLEX;
1287 			pdev = d->mixer_dev;
1288 	    		p->mixers = 1; /* default: one mixer */
1289 	    		p->inputs = pdev->si_drv1? mix_getdevs(pdev->si_drv1) : 0;
1290 	    		p->left = p->right = 100;
1291 			if (wrch)
1292 				CHN_UNLOCK(wrch);
1293 			if (rdch)
1294 				CHN_UNLOCK(rdch);
1295 			PCM_UNLOCK(d);
1296 		}
1297 		break;
1298 
1299     	case AIOSTOP:
1300 		if (*arg_i == AIOSYNC_PLAY && wrch) {
1301 			CHN_LOCK(wrch);
1302 			*arg_i = chn_abort(wrch);
1303 			CHN_UNLOCK(wrch);
1304 		} else if (*arg_i == AIOSYNC_CAPTURE && rdch) {
1305 			CHN_LOCK(rdch);
1306 			*arg_i = chn_abort(rdch);
1307 			CHN_UNLOCK(rdch);
1308 		} else {
1309 	   	 	printf("AIOSTOP: bad channel 0x%x\n", *arg_i);
1310 	    		*arg_i = 0;
1311 		}
1312 		break;
1313 
1314     	case AIOSYNC:
1315 		printf("AIOSYNC chan 0x%03lx pos %lu unimplemented\n",
1316 	    		((snd_sync_parm *)arg)->chan, ((snd_sync_parm *)arg)->pos);
1317 		break;
1318 #endif
1319 	/*
1320 	 * here follow the standard ioctls (filio.h etc.)
1321 	 */
1322     	case FIONREAD: /* get # bytes to read */
1323 		if (rdch) {
1324 			CHN_LOCK(rdch);
1325 /*			if (rdch && rdch->bufhard.dl)
1326 				while (chn_rdfeed(rdch) == 0);
1327 */
1328 			*arg_i = sndbuf_getready(rdch->bufsoft);
1329 			CHN_UNLOCK(rdch);
1330 		} else {
1331 			*arg_i = 0;
1332 			ret = EINVAL;
1333 		}
1334 		break;
1335 
1336     	case FIOASYNC: /*set/clear async i/o */
1337 		DEB( printf("FIOASYNC\n") ; )
1338 		break;
1339 
1340     	case SNDCTL_DSP_NONBLOCK: /* set non-blocking i/o */
1341     	case FIONBIO: /* set/clear non-blocking i/o */
1342 		if (rdch) {
1343 			CHN_LOCK(rdch);
1344 			if (cmd == SNDCTL_DSP_NONBLOCK || *arg_i)
1345 				rdch->flags |= CHN_F_NBIO;
1346 			else
1347 				rdch->flags &= ~CHN_F_NBIO;
1348 			CHN_UNLOCK(rdch);
1349 		}
1350 		if (wrch) {
1351 			CHN_LOCK(wrch);
1352 			if (cmd == SNDCTL_DSP_NONBLOCK || *arg_i)
1353 				wrch->flags |= CHN_F_NBIO;
1354 			else
1355 				wrch->flags &= ~CHN_F_NBIO;
1356 			CHN_UNLOCK(wrch);
1357 		}
1358 		break;
1359 
1360     	/*
1361 	 * Finally, here is the linux-compatible ioctl interface
1362 	 */
1363 #define THE_REAL_SNDCTL_DSP_GETBLKSIZE _IOWR('P', 4, int)
1364     	case THE_REAL_SNDCTL_DSP_GETBLKSIZE:
1365     	case SNDCTL_DSP_GETBLKSIZE:
1366 		chn = wrch ? wrch : rdch;
1367 		if (chn) {
1368 			CHN_LOCK(chn);
1369 			*arg_i = sndbuf_getblksz(chn->bufsoft);
1370 			CHN_UNLOCK(chn);
1371 		} else {
1372 			*arg_i = 0;
1373 			ret = EINVAL;
1374 		}
1375 		break;
1376 
1377     	case SNDCTL_DSP_SETBLKSIZE:
1378 		RANGE(*arg_i, 16, 65536);
1379 		PCM_ACQUIRE_QUICK(d);
1380 		if (wrch) {
1381 			CHN_LOCK(wrch);
1382 			chn_setblocksize(wrch, 2, *arg_i);
1383 			CHN_UNLOCK(wrch);
1384 		}
1385 		if (rdch) {
1386 			CHN_LOCK(rdch);
1387 			chn_setblocksize(rdch, 2, *arg_i);
1388 			CHN_UNLOCK(rdch);
1389 		}
1390 		PCM_RELEASE_QUICK(d);
1391 		break;
1392 
1393     	case SNDCTL_DSP_RESET:
1394 		DEB(printf("dsp reset\n"));
1395 		if (wrch) {
1396 			CHN_LOCK(wrch);
1397 			chn_abort(wrch);
1398 			chn_resetbuf(wrch);
1399 			CHN_UNLOCK(wrch);
1400 		}
1401 		if (rdch) {
1402 			CHN_LOCK(rdch);
1403 			chn_abort(rdch);
1404 			chn_resetbuf(rdch);
1405 			CHN_UNLOCK(rdch);
1406 		}
1407 		break;
1408 
1409     	case SNDCTL_DSP_SYNC:
1410 		DEB(printf("dsp sync\n"));
1411 		/* chn_sync may sleep */
1412 		if (wrch) {
1413 			CHN_LOCK(wrch);
1414 			chn_sync(wrch, 0);
1415 			CHN_UNLOCK(wrch);
1416 		}
1417 		break;
1418 
1419     	case SNDCTL_DSP_SPEED:
1420 		/* chn_setspeed may sleep */
1421 		tmp = 0;
1422 		PCM_ACQUIRE_QUICK(d);
1423 		if (wrch) {
1424 			CHN_LOCK(wrch);
1425 			ret = chn_setspeed(wrch, *arg_i);
1426 			tmp = wrch->speed;
1427 			CHN_UNLOCK(wrch);
1428 		}
1429 		if (rdch && ret == 0) {
1430 			CHN_LOCK(rdch);
1431 			ret = chn_setspeed(rdch, *arg_i);
1432 			if (tmp == 0)
1433 				tmp = rdch->speed;
1434 			CHN_UNLOCK(rdch);
1435 		}
1436 		PCM_RELEASE_QUICK(d);
1437 		*arg_i = tmp;
1438 		break;
1439 
1440     	case SOUND_PCM_READ_RATE:
1441 		chn = wrch ? wrch : rdch;
1442 		if (chn) {
1443 			CHN_LOCK(chn);
1444 			*arg_i = chn->speed;
1445 			CHN_UNLOCK(chn);
1446 		} else {
1447 			*arg_i = 0;
1448 			ret = EINVAL;
1449 		}
1450 		break;
1451 
1452     	case SNDCTL_DSP_STEREO:
1453 		tmp = -1;
1454 		*arg_i = (*arg_i)? 2 : 1;
1455 		PCM_ACQUIRE_QUICK(d);
1456 		if (wrch) {
1457 			CHN_LOCK(wrch);
1458 			ret = chn_setformat(wrch,
1459 			    SND_FORMAT(wrch->format, *arg_i, 0));
1460 			tmp = (AFMT_CHANNEL(wrch->format) > 1)? 1 : 0;
1461 			CHN_UNLOCK(wrch);
1462 		}
1463 		if (rdch && ret == 0) {
1464 			CHN_LOCK(rdch);
1465 			ret = chn_setformat(rdch,
1466 			    SND_FORMAT(rdch->format, *arg_i, 0));
1467 			if (tmp == -1)
1468 				tmp = (AFMT_CHANNEL(rdch->format) > 1)? 1 : 0;
1469 			CHN_UNLOCK(rdch);
1470 		}
1471 		PCM_RELEASE_QUICK(d);
1472 		*arg_i = tmp;
1473 		break;
1474 
1475     	case SOUND_PCM_WRITE_CHANNELS:
1476 /*	case SNDCTL_DSP_CHANNELS: ( == SOUND_PCM_WRITE_CHANNELS) */
1477 		if (*arg_i < 0) {
1478 			*arg_i = 0;
1479 			ret = EINVAL;
1480 			break;
1481 		}
1482 		if (*arg_i != 0) {
1483 			struct pcmchan_matrix *m;
1484 			uint32_t ext;
1485 
1486 			tmp = 0;
1487 			if (*arg_i > SND_CHN_MAX)
1488 				*arg_i = SND_CHN_MAX;
1489 
1490 			m = feeder_matrix_default_channel_map(*arg_i);
1491 			if (m != NULL)
1492 				ext = m->ext;
1493 			else
1494 				ext = 0;
1495 
1496 			PCM_ACQUIRE_QUICK(d);
1497 	  		if (wrch) {
1498 				CHN_LOCK(wrch);
1499 				ret = chn_setformat(wrch,
1500 				    SND_FORMAT(wrch->format, *arg_i, ext));
1501 				tmp = AFMT_CHANNEL(wrch->format);
1502 				CHN_UNLOCK(wrch);
1503 			}
1504 			if (rdch && ret == 0) {
1505 				CHN_LOCK(rdch);
1506 				ret = chn_setformat(rdch,
1507 				    SND_FORMAT(rdch->format, *arg_i, ext));
1508 				if (tmp == 0)
1509 					tmp = AFMT_CHANNEL(rdch->format);
1510 				CHN_UNLOCK(rdch);
1511 			}
1512 			PCM_RELEASE_QUICK(d);
1513 			*arg_i = tmp;
1514 		} else {
1515 			chn = wrch ? wrch : rdch;
1516 			CHN_LOCK(chn);
1517 			*arg_i = AFMT_CHANNEL(chn->format);
1518 			CHN_UNLOCK(chn);
1519 		}
1520 		break;
1521 
1522     	case SOUND_PCM_READ_CHANNELS:
1523 		chn = wrch ? wrch : rdch;
1524 		if (chn) {
1525 			CHN_LOCK(chn);
1526 			*arg_i = AFMT_CHANNEL(chn->format);
1527 			CHN_UNLOCK(chn);
1528 		} else {
1529 			*arg_i = 0;
1530 			ret = EINVAL;
1531 		}
1532 		break;
1533 
1534     	case SNDCTL_DSP_GETFMTS:	/* returns a mask of supported fmts */
1535 		chn = wrch ? wrch : rdch;
1536 		if (chn) {
1537 			CHN_LOCK(chn);
1538 			*arg_i = chn_getformats(chn);
1539 			CHN_UNLOCK(chn);
1540 		} else {
1541 			*arg_i = 0;
1542 			ret = EINVAL;
1543 		}
1544 		break;
1545 
1546     	case SNDCTL_DSP_SETFMT:	/* sets _one_ format */
1547 		if (*arg_i != AFMT_QUERY) {
1548 			tmp = 0;
1549 			PCM_ACQUIRE_QUICK(d);
1550 			if (wrch) {
1551 				CHN_LOCK(wrch);
1552 				ret = chn_setformat(wrch, SND_FORMAT(*arg_i,
1553 				    AFMT_CHANNEL(wrch->format),
1554 				    AFMT_EXTCHANNEL(wrch->format)));
1555 				tmp = wrch->format;
1556 				CHN_UNLOCK(wrch);
1557 			}
1558 			if (rdch && ret == 0) {
1559 				CHN_LOCK(rdch);
1560 				ret = chn_setformat(rdch, SND_FORMAT(*arg_i,
1561 				    AFMT_CHANNEL(rdch->format),
1562 				    AFMT_EXTCHANNEL(rdch->format)));
1563 				if (tmp == 0)
1564 					tmp = rdch->format;
1565 				CHN_UNLOCK(rdch);
1566 			}
1567 			PCM_RELEASE_QUICK(d);
1568 			*arg_i = AFMT_ENCODING(tmp);
1569 		} else {
1570 			chn = wrch ? wrch : rdch;
1571 			CHN_LOCK(chn);
1572 			*arg_i = AFMT_ENCODING(chn->format);
1573 			CHN_UNLOCK(chn);
1574 		}
1575 		break;
1576 
1577     	case SNDCTL_DSP_SETFRAGMENT:
1578 		DEB(printf("SNDCTL_DSP_SETFRAGMENT 0x%08x\n", *(int *)arg));
1579 		{
1580 			uint32_t fragln = (*arg_i) & 0x0000ffff;
1581 			uint32_t maxfrags = ((*arg_i) & 0xffff0000) >> 16;
1582 			uint32_t fragsz;
1583 			uint32_t r_maxfrags, r_fragsz;
1584 
1585 			RANGE(fragln, 4, 16);
1586 			fragsz = 1 << fragln;
1587 
1588 			if (maxfrags == 0)
1589 				maxfrags = CHN_2NDBUFMAXSIZE / fragsz;
1590 			if (maxfrags < 2)
1591 				maxfrags = 2;
1592 			if (maxfrags * fragsz > CHN_2NDBUFMAXSIZE)
1593 				maxfrags = CHN_2NDBUFMAXSIZE / fragsz;
1594 
1595 			DEB(printf("SNDCTL_DSP_SETFRAGMENT %d frags, %d sz\n", maxfrags, fragsz));
1596 			PCM_ACQUIRE_QUICK(d);
1597 		    	if (rdch) {
1598 				CHN_LOCK(rdch);
1599 				ret = chn_setblocksize(rdch, maxfrags, fragsz);
1600 				r_maxfrags = sndbuf_getblkcnt(rdch->bufsoft);
1601 				r_fragsz = sndbuf_getblksz(rdch->bufsoft);
1602 				CHN_UNLOCK(rdch);
1603 			} else {
1604 				r_maxfrags = maxfrags;
1605 				r_fragsz = fragsz;
1606 			}
1607 		    	if (wrch && ret == 0) {
1608 				CHN_LOCK(wrch);
1609 				ret = chn_setblocksize(wrch, maxfrags, fragsz);
1610  				maxfrags = sndbuf_getblkcnt(wrch->bufsoft);
1611 				fragsz = sndbuf_getblksz(wrch->bufsoft);
1612 				CHN_UNLOCK(wrch);
1613 			} else { /* use whatever came from the read channel */
1614 				maxfrags = r_maxfrags;
1615 				fragsz = r_fragsz;
1616 			}
1617 			PCM_RELEASE_QUICK(d);
1618 
1619 			fragln = 0;
1620 			while (fragsz > 1) {
1621 				fragln++;
1622 				fragsz >>= 1;
1623 			}
1624 	    		*arg_i = (maxfrags << 16) | fragln;
1625 		}
1626 		break;
1627 
1628     	case SNDCTL_DSP_GETISPACE:
1629 		/* return the size of data available in the input queue */
1630 		{
1631 	    		audio_buf_info *a = (audio_buf_info *)arg;
1632 	    		if (rdch) {
1633 	        		struct snd_dbuf *bs = rdch->bufsoft;
1634 
1635 				CHN_LOCK(rdch);
1636 				a->bytes = sndbuf_getready(bs);
1637 	        		a->fragments = a->bytes / sndbuf_getblksz(bs);
1638 	        		a->fragstotal = sndbuf_getblkcnt(bs);
1639 	        		a->fragsize = sndbuf_getblksz(bs);
1640 				CHN_UNLOCK(rdch);
1641 	    		} else
1642 				ret = EINVAL;
1643 		}
1644 		break;
1645 
1646     	case SNDCTL_DSP_GETOSPACE:
1647 		/* return space available in the output queue */
1648 		{
1649 	    		audio_buf_info *a = (audio_buf_info *)arg;
1650 	    		if (wrch) {
1651 	        		struct snd_dbuf *bs = wrch->bufsoft;
1652 
1653 				CHN_LOCK(wrch);
1654 				/* XXX abusive DMA update: chn_wrupdate(wrch); */
1655 				a->bytes = sndbuf_getfree(bs);
1656 	        		a->fragments = a->bytes / sndbuf_getblksz(bs);
1657 	        		a->fragstotal = sndbuf_getblkcnt(bs);
1658 	        		a->fragsize = sndbuf_getblksz(bs);
1659 				CHN_UNLOCK(wrch);
1660 	    		} else
1661 				ret = EINVAL;
1662 		}
1663 		break;
1664 
1665     	case SNDCTL_DSP_GETIPTR:
1666 		{
1667 	    		count_info *a = (count_info *)arg;
1668 	    		if (rdch) {
1669 	        		struct snd_dbuf *bs = rdch->bufsoft;
1670 
1671 				CHN_LOCK(rdch);
1672 				/* XXX abusive DMA update: chn_rdupdate(rdch); */
1673 	        		a->bytes = sndbuf_gettotal(bs);
1674 	        		a->blocks = sndbuf_getblocks(bs) - rdch->blocks;
1675 	        		a->ptr = sndbuf_getfreeptr(bs);
1676 				rdch->blocks = sndbuf_getblocks(bs);
1677 				CHN_UNLOCK(rdch);
1678 	    		} else
1679 				ret = EINVAL;
1680 		}
1681 		break;
1682 
1683     	case SNDCTL_DSP_GETOPTR:
1684 		{
1685 	    		count_info *a = (count_info *)arg;
1686 	    		if (wrch) {
1687 	        		struct snd_dbuf *bs = wrch->bufsoft;
1688 
1689 				CHN_LOCK(wrch);
1690 				/* XXX abusive DMA update: chn_wrupdate(wrch); */
1691 	        		a->bytes = sndbuf_gettotal(bs);
1692 	        		a->blocks = sndbuf_getblocks(bs) - wrch->blocks;
1693 	        		a->ptr = sndbuf_getreadyptr(bs);
1694 				wrch->blocks = sndbuf_getblocks(bs);
1695 				CHN_UNLOCK(wrch);
1696 	    		} else
1697 				ret = EINVAL;
1698 		}
1699 		break;
1700 
1701     	case SNDCTL_DSP_GETCAPS:
1702 		PCM_LOCK(d);
1703 		*arg_i = PCM_CAP_REALTIME | PCM_CAP_MMAP | PCM_CAP_TRIGGER;
1704 		if (rdch && wrch && !(dsp_get_flags(i_dev) & SD_F_SIMPLEX))
1705 			*arg_i |= PCM_CAP_DUPLEX;
1706 		PCM_UNLOCK(d);
1707 		break;
1708 
1709     	case SOUND_PCM_READ_BITS:
1710 		chn = wrch ? wrch : rdch;
1711 		if (chn) {
1712 			CHN_LOCK(chn);
1713 			if (chn->format & AFMT_8BIT)
1714 				*arg_i = 8;
1715 			else if (chn->format & AFMT_16BIT)
1716 				*arg_i = 16;
1717 			else if (chn->format & AFMT_24BIT)
1718 				*arg_i = 24;
1719 			else if (chn->format & AFMT_32BIT)
1720 				*arg_i = 32;
1721 			else
1722 				ret = EINVAL;
1723 			CHN_UNLOCK(chn);
1724 		} else {
1725 			*arg_i = 0;
1726 			ret = EINVAL;
1727 		}
1728 		break;
1729 
1730     	case SNDCTL_DSP_SETTRIGGER:
1731 		if (rdch) {
1732 			CHN_LOCK(rdch);
1733 			rdch->flags &= ~CHN_F_NOTRIGGER;
1734 		    	if (*arg_i & PCM_ENABLE_INPUT)
1735 				chn_start(rdch, 1);
1736 			else {
1737 				chn_abort(rdch);
1738 				chn_resetbuf(rdch);
1739 				rdch->flags |= CHN_F_NOTRIGGER;
1740 			}
1741 			CHN_UNLOCK(rdch);
1742 		}
1743 		if (wrch) {
1744 			CHN_LOCK(wrch);
1745 			wrch->flags &= ~CHN_F_NOTRIGGER;
1746 		    	if (*arg_i & PCM_ENABLE_OUTPUT)
1747 				chn_start(wrch, 1);
1748 			else {
1749 				chn_abort(wrch);
1750 				chn_resetbuf(wrch);
1751 				wrch->flags |= CHN_F_NOTRIGGER;
1752 			}
1753 			CHN_UNLOCK(wrch);
1754 		}
1755 		break;
1756 
1757     	case SNDCTL_DSP_GETTRIGGER:
1758 		*arg_i = 0;
1759 		if (wrch) {
1760 			CHN_LOCK(wrch);
1761 			if (wrch->flags & CHN_F_TRIGGERED)
1762 				*arg_i |= PCM_ENABLE_OUTPUT;
1763 			CHN_UNLOCK(wrch);
1764 		}
1765 		if (rdch) {
1766 			CHN_LOCK(rdch);
1767 			if (rdch->flags & CHN_F_TRIGGERED)
1768 				*arg_i |= PCM_ENABLE_INPUT;
1769 			CHN_UNLOCK(rdch);
1770 		}
1771 		break;
1772 
1773 	case SNDCTL_DSP_GETODELAY:
1774 		if (wrch) {
1775 	        	struct snd_dbuf *bs = wrch->bufsoft;
1776 
1777 			CHN_LOCK(wrch);
1778 			/* XXX abusive DMA update: chn_wrupdate(wrch); */
1779 			*arg_i = sndbuf_getready(bs);
1780 			CHN_UNLOCK(wrch);
1781 		} else
1782 			ret = EINVAL;
1783 		break;
1784 
1785     	case SNDCTL_DSP_POST:
1786 		if (wrch) {
1787 			CHN_LOCK(wrch);
1788 			wrch->flags &= ~CHN_F_NOTRIGGER;
1789 			chn_start(wrch, 1);
1790 			CHN_UNLOCK(wrch);
1791 		}
1792 		break;
1793 
1794 	case SNDCTL_DSP_SETDUPLEX:
1795 		/*
1796 		 * switch to full-duplex mode if card is in half-duplex
1797 		 * mode and is able to work in full-duplex mode
1798 		 */
1799 		PCM_LOCK(d);
1800 		if (rdch && wrch && (dsp_get_flags(i_dev) & SD_F_SIMPLEX))
1801 			dsp_set_flags(i_dev, dsp_get_flags(i_dev)^SD_F_SIMPLEX);
1802 		PCM_UNLOCK(d);
1803 		break;
1804 
1805 	/*
1806 	 * The following four ioctls are simple wrappers around mixer_ioctl
1807 	 * with no further processing.  xcmd is short for "translated
1808 	 * command".
1809 	 */
1810 	case SNDCTL_DSP_GETRECVOL:
1811 		if (xcmd == 0) {
1812 			xcmd = SOUND_MIXER_READ_RECLEV;
1813 			chn = rdch;
1814 		}
1815 		/* FALLTHROUGH */
1816 	case SNDCTL_DSP_SETRECVOL:
1817 		if (xcmd == 0) {
1818 			xcmd = SOUND_MIXER_WRITE_RECLEV;
1819 			chn = rdch;
1820 		}
1821 		/* FALLTHROUGH */
1822 	case SNDCTL_DSP_GETPLAYVOL:
1823 		if (xcmd == 0) {
1824 			xcmd = SOUND_MIXER_READ_PCM;
1825 			chn = wrch;
1826 		}
1827 		/* FALLTHROUGH */
1828 	case SNDCTL_DSP_SETPLAYVOL:
1829 		if (xcmd == 0) {
1830 			xcmd = SOUND_MIXER_WRITE_PCM;
1831 			chn = wrch;
1832 		}
1833 
1834 		ret = dsp_ioctl_channel(i_dev, chn, xcmd, arg);
1835 		if (ret != -1) {
1836 			PCM_GIANT_EXIT(d);
1837 			return (ret);
1838 		}
1839 
1840 		if (d->mixer_dev != NULL) {
1841 			PCM_ACQUIRE_QUICK(d);
1842 			ret = mixer_ioctl_cmd(d->mixer_dev, xcmd, arg, -1, td,
1843 			    MIXER_CMD_DIRECT);
1844 			PCM_RELEASE_QUICK(d);
1845 		} else
1846 			ret = ENOTSUP;
1847 
1848 		break;
1849 
1850 	case SNDCTL_DSP_GET_RECSRC_NAMES:
1851 	case SNDCTL_DSP_GET_RECSRC:
1852 	case SNDCTL_DSP_SET_RECSRC:
1853 		if (d->mixer_dev != NULL) {
1854 			PCM_ACQUIRE_QUICK(d);
1855 			ret = mixer_ioctl_cmd(d->mixer_dev, cmd, arg, -1, td,
1856 			    MIXER_CMD_DIRECT);
1857 			PCM_RELEASE_QUICK(d);
1858 		} else
1859 			ret = ENOTSUP;
1860 		break;
1861 
1862 	/*
1863 	 * The following 3 ioctls aren't very useful at the moment.  For
1864 	 * now, only a single channel is associated with a cdev (/dev/dspN
1865 	 * instance), so there's only a single output routing to use (i.e.,
1866 	 * the wrch bound to this cdev).
1867 	 */
1868 	case SNDCTL_DSP_GET_PLAYTGT_NAMES:
1869 		{
1870 			oss_mixer_enuminfo *ei;
1871 			ei = (oss_mixer_enuminfo *)arg;
1872 			ei->dev = 0;
1873 			ei->ctrl = 0;
1874 			ei->version = 0; /* static for now */
1875 			ei->strindex[0] = 0;
1876 
1877 			if (wrch != NULL) {
1878 				ei->nvalues = 1;
1879 				strlcpy(ei->strings, wrch->name,
1880 					sizeof(ei->strings));
1881 			} else {
1882 				ei->nvalues = 0;
1883 				ei->strings[0] = '\0';
1884 			}
1885 		}
1886 		break;
1887 	case SNDCTL_DSP_GET_PLAYTGT:
1888 	case SNDCTL_DSP_SET_PLAYTGT:	/* yes, they are the same for now */
1889 		/*
1890 		 * Re: SET_PLAYTGT
1891 		 *   OSSv4: "The value that was accepted by the device will
1892 		 *   be returned back in the variable pointed by the
1893 		 *   argument."
1894 		 */
1895 		if (wrch != NULL)
1896 			*arg_i = 0;
1897 		else
1898 			ret = EINVAL;
1899 		break;
1900 
1901 	case SNDCTL_DSP_SILENCE:
1902 	/*
1903 	 * Flush the software (pre-feed) buffer, but try to minimize playback
1904 	 * interruption.  (I.e., record unplayed samples with intent to
1905 	 * restore by SNDCTL_DSP_SKIP.) Intended for application "pause"
1906 	 * functionality.
1907 	 */
1908 		if (wrch == NULL)
1909 			ret = EINVAL;
1910 		else {
1911 			struct snd_dbuf *bs;
1912 			CHN_LOCK(wrch);
1913 			while (wrch->inprog != 0)
1914 				cv_wait(&wrch->cv, wrch->lock);
1915 			bs = wrch->bufsoft;
1916 			if ((bs->shadbuf != NULL) && (sndbuf_getready(bs) > 0)) {
1917 				bs->sl = sndbuf_getready(bs);
1918 				sndbuf_dispose(bs, bs->shadbuf, sndbuf_getready(bs));
1919 				sndbuf_fillsilence(bs);
1920 				chn_start(wrch, 0);
1921 			}
1922 			CHN_UNLOCK(wrch);
1923 		}
1924 		break;
1925 
1926 	case SNDCTL_DSP_SKIP:
1927 	/*
1928 	 * OSSv4 docs: "This ioctl call discards all unplayed samples in the
1929 	 * playback buffer by moving the current write position immediately
1930 	 * before the point where the device is currently reading the samples."
1931 	 */
1932 		if (wrch == NULL)
1933 			ret = EINVAL;
1934 		else {
1935 			struct snd_dbuf *bs;
1936 			CHN_LOCK(wrch);
1937 			while (wrch->inprog != 0)
1938 				cv_wait(&wrch->cv, wrch->lock);
1939 			bs = wrch->bufsoft;
1940 			if ((bs->shadbuf != NULL) && (bs->sl > 0)) {
1941 				sndbuf_softreset(bs);
1942 				sndbuf_acquire(bs, bs->shadbuf, bs->sl);
1943 				bs->sl = 0;
1944 				chn_start(wrch, 0);
1945 			}
1946 			CHN_UNLOCK(wrch);
1947 		}
1948 		break;
1949 
1950 	case SNDCTL_DSP_CURRENT_OPTR:
1951 	case SNDCTL_DSP_CURRENT_IPTR:
1952 	/**
1953 	 * @note Changing formats resets the buffer counters, which differs
1954 	 * 	 from the 4Front drivers.  However, I don't expect this to be
1955 	 * 	 much of a problem.
1956 	 *
1957 	 * @note In a test where @c CURRENT_OPTR is called immediately after write
1958 	 * 	 returns, this driver is about 32K samples behind whereas
1959 	 * 	 4Front's is about 8K samples behind.  Should determine source
1960 	 * 	 of discrepancy, even if only out of curiosity.
1961 	 *
1962 	 * @todo Actually test SNDCTL_DSP_CURRENT_IPTR.
1963 	 */
1964 		chn = (cmd == SNDCTL_DSP_CURRENT_OPTR) ? wrch : rdch;
1965 		if (chn == NULL)
1966 			ret = EINVAL;
1967 		else {
1968 			struct snd_dbuf *bs;
1969 			/* int tmp; */
1970 
1971 			oss_count_t *oc = (oss_count_t *)arg;
1972 
1973 			CHN_LOCK(chn);
1974 			bs = chn->bufsoft;
1975 #if 0
1976 			tmp = (sndbuf_getsize(b) + chn_getptr(chn) - sndbuf_gethwptr(b)) % sndbuf_getsize(b);
1977 			oc->samples = (sndbuf_gettotal(b) + tmp) / sndbuf_getalign(b);
1978 			oc->fifo_samples = (sndbuf_getready(b) - tmp) / sndbuf_getalign(b);
1979 #else
1980 			oc->samples = sndbuf_gettotal(bs) / sndbuf_getalign(bs);
1981 			oc->fifo_samples = sndbuf_getready(bs) / sndbuf_getalign(bs);
1982 #endif
1983 			CHN_UNLOCK(chn);
1984 		}
1985 		break;
1986 
1987 	case SNDCTL_DSP_HALT_OUTPUT:
1988 	case SNDCTL_DSP_HALT_INPUT:
1989 		chn = (cmd == SNDCTL_DSP_HALT_OUTPUT) ? wrch : rdch;
1990 		if (chn == NULL)
1991 			ret = EINVAL;
1992 		else {
1993 			CHN_LOCK(chn);
1994 			chn_abort(chn);
1995 			CHN_UNLOCK(chn);
1996 		}
1997 		break;
1998 
1999 	case SNDCTL_DSP_LOW_WATER:
2000 	/*
2001 	 * Set the number of bytes required to attract attention by
2002 	 * select/poll.
2003 	 */
2004 		if (wrch != NULL) {
2005 			CHN_LOCK(wrch);
2006 			wrch->lw = (*arg_i > 1) ? *arg_i : 1;
2007 			CHN_UNLOCK(wrch);
2008 		}
2009 		if (rdch != NULL) {
2010 			CHN_LOCK(rdch);
2011 			rdch->lw = (*arg_i > 1) ? *arg_i : 1;
2012 			CHN_UNLOCK(rdch);
2013 		}
2014 		break;
2015 
2016 	case SNDCTL_DSP_GETERROR:
2017 	/*
2018 	 * OSSv4 docs:  "All errors and counters will automatically be
2019 	 * cleared to zeroes after the call so each call will return only
2020 	 * the errors that occurred after the previous invocation. ... The
2021 	 * play_underruns and rec_overrun fields are the only useful fields
2022 	 * returned by OSS 4.0."
2023 	 */
2024 		{
2025 			audio_errinfo *ei = (audio_errinfo *)arg;
2026 
2027 			bzero((void *)ei, sizeof(*ei));
2028 
2029 			if (wrch != NULL) {
2030 				CHN_LOCK(wrch);
2031 				ei->play_underruns = wrch->xruns;
2032 				wrch->xruns = 0;
2033 				CHN_UNLOCK(wrch);
2034 			}
2035 			if (rdch != NULL) {
2036 				CHN_LOCK(rdch);
2037 				ei->rec_overruns = rdch->xruns;
2038 				rdch->xruns = 0;
2039 				CHN_UNLOCK(rdch);
2040 			}
2041 		}
2042 		break;
2043 
2044 	case SNDCTL_DSP_SYNCGROUP:
2045 		PCM_ACQUIRE_QUICK(d);
2046 		ret = dsp_oss_syncgroup(wrch, rdch, (oss_syncgroup *)arg);
2047 		PCM_RELEASE_QUICK(d);
2048 		break;
2049 
2050 	case SNDCTL_DSP_SYNCSTART:
2051 		PCM_ACQUIRE_QUICK(d);
2052 		ret = dsp_oss_syncstart(*arg_i);
2053 		PCM_RELEASE_QUICK(d);
2054 		break;
2055 
2056 	case SNDCTL_DSP_POLICY:
2057 		PCM_ACQUIRE_QUICK(d);
2058 		ret = dsp_oss_policy(wrch, rdch, *arg_i);
2059 		PCM_RELEASE_QUICK(d);
2060 		break;
2061 
2062 	case SNDCTL_DSP_COOKEDMODE:
2063 		PCM_ACQUIRE_QUICK(d);
2064 		if (!(dsp_get_flags(i_dev) & SD_F_BITPERFECT))
2065 			ret = dsp_oss_cookedmode(wrch, rdch, *arg_i);
2066 		PCM_RELEASE_QUICK(d);
2067 		break;
2068 	case SNDCTL_DSP_GET_CHNORDER:
2069 		PCM_ACQUIRE_QUICK(d);
2070 		ret = dsp_oss_getchnorder(wrch, rdch, (unsigned long long *)arg);
2071 		PCM_RELEASE_QUICK(d);
2072 		break;
2073 	case SNDCTL_DSP_SET_CHNORDER:
2074 		PCM_ACQUIRE_QUICK(d);
2075 		ret = dsp_oss_setchnorder(wrch, rdch, (unsigned long long *)arg);
2076 		PCM_RELEASE_QUICK(d);
2077 		break;
2078 	case SNDCTL_DSP_GETCHANNELMASK:		/* XXX vlc */
2079 		PCM_ACQUIRE_QUICK(d);
2080 		ret = dsp_oss_getchannelmask(wrch, rdch, (int *)arg);
2081 		PCM_RELEASE_QUICK(d);
2082 		break;
2083 	case SNDCTL_DSP_BIND_CHANNEL:		/* XXX what?!? */
2084 		ret = EINVAL;
2085 		break;
2086 #ifdef	OSSV4_EXPERIMENT
2087 	/*
2088 	 * XXX The following ioctls are not yet supported and just return
2089 	 * EINVAL.
2090 	 */
2091 	case SNDCTL_DSP_GETOPEAKS:
2092 	case SNDCTL_DSP_GETIPEAKS:
2093 		chn = (cmd == SNDCTL_DSP_GETOPEAKS) ? wrch : rdch;
2094 		if (chn == NULL)
2095 			ret = EINVAL;
2096 		else {
2097 			oss_peaks_t *op = (oss_peaks_t *)arg;
2098 			int lpeak, rpeak;
2099 
2100 			CHN_LOCK(chn);
2101 			ret = chn_getpeaks(chn, &lpeak, &rpeak);
2102 			if (ret == -1)
2103 				ret = EINVAL;
2104 			else {
2105 				(*op)[0] = lpeak;
2106 				(*op)[1] = rpeak;
2107 			}
2108 			CHN_UNLOCK(chn);
2109 		}
2110 		break;
2111 
2112 	/*
2113 	 * XXX Once implemented, revisit this for proper cv protection
2114 	 *     (if necessary).
2115 	 */
2116 	case SNDCTL_GETLABEL:
2117 		ret = dsp_oss_getlabel(wrch, rdch, (oss_label_t *)arg);
2118 		break;
2119 	case SNDCTL_SETLABEL:
2120 		ret = dsp_oss_setlabel(wrch, rdch, (oss_label_t *)arg);
2121 		break;
2122 	case SNDCTL_GETSONG:
2123 		ret = dsp_oss_getsong(wrch, rdch, (oss_longname_t *)arg);
2124 		break;
2125 	case SNDCTL_SETSONG:
2126 		ret = dsp_oss_setsong(wrch, rdch, (oss_longname_t *)arg);
2127 		break;
2128 	case SNDCTL_SETNAME:
2129 		ret = dsp_oss_setname(wrch, rdch, (oss_longname_t *)arg);
2130 		break;
2131 #if 0
2132 	/**
2133 	 * @note The S/PDIF interface ioctls, @c SNDCTL_DSP_READCTL and
2134 	 * @c SNDCTL_DSP_WRITECTL have been omitted at the suggestion of
2135 	 * 4Front Technologies.
2136 	 */
2137 	case SNDCTL_DSP_READCTL:
2138 	case SNDCTL_DSP_WRITECTL:
2139 		ret = EINVAL;
2140 		break;
2141 #endif	/* !0 (explicitly omitted ioctls) */
2142 
2143 #endif	/* !OSSV4_EXPERIMENT */
2144     	case SNDCTL_DSP_MAPINBUF:
2145     	case SNDCTL_DSP_MAPOUTBUF:
2146     	case SNDCTL_DSP_SETSYNCRO:
2147 		/* undocumented */
2148 
2149     	case SNDCTL_DSP_SUBDIVIDE:
2150     	case SOUND_PCM_WRITE_FILTER:
2151     	case SOUND_PCM_READ_FILTER:
2152 		/* dunno what these do, don't sound important */
2153 
2154     	default:
2155 		DEB(printf("default ioctl fn 0x%08lx fail\n", cmd));
2156 		ret = EINVAL;
2157 		break;
2158     	}
2159 
2160 	PCM_GIANT_LEAVE(d);
2161 
2162     	return (ret);
2163 }
2164 
2165 static int
2166 dsp_poll(struct cdev *i_dev, int events, struct thread *td)
2167 {
2168 	struct snddev_info *d;
2169 	struct pcm_channel *wrch, *rdch;
2170 	int ret, e;
2171 
2172 	d = dsp_get_info(i_dev);
2173 	if (!DSP_REGISTERED(d, i_dev))
2174 		return (EBADF);
2175 
2176 	PCM_GIANT_ENTER(d);
2177 
2178 	wrch = NULL;
2179 	rdch = NULL;
2180 	ret = 0;
2181 
2182 	getchns(i_dev, &rdch, &wrch, SD_F_PRIO_RD | SD_F_PRIO_WR);
2183 
2184 	if (wrch != NULL && !(wrch->flags & CHN_F_DEAD)) {
2185 		e = (events & (POLLOUT | POLLWRNORM));
2186 		if (e)
2187 			ret |= chn_poll(wrch, e, td);
2188 	}
2189 
2190 	if (rdch != NULL && !(rdch->flags & CHN_F_DEAD)) {
2191 		e = (events & (POLLIN | POLLRDNORM));
2192 		if (e)
2193 			ret |= chn_poll(rdch, e, td);
2194 	}
2195 
2196 	relchns(i_dev, rdch, wrch, SD_F_PRIO_RD | SD_F_PRIO_WR);
2197 
2198 	PCM_GIANT_LEAVE(d);
2199 
2200 	return (ret);
2201 }
2202 
2203 static int
2204 dsp_mmap(struct cdev *i_dev, vm_ooffset_t offset, vm_paddr_t *paddr,
2205     int nprot, vm_memattr_t *memattr)
2206 {
2207 
2208 	/* XXX memattr is not honored */
2209 	*paddr = vtophys(offset);
2210 	return (0);
2211 }
2212 
2213 static int
2214 dsp_mmap_single(struct cdev *i_dev, vm_ooffset_t *offset,
2215     vm_size_t size, struct vm_object **object, int nprot)
2216 {
2217 	struct snddev_info *d;
2218 	struct pcm_channel *wrch, *rdch, *c;
2219 
2220 	/*
2221 	 * Reject PROT_EXEC by default. It just doesn't makes sense.
2222 	 * Unfortunately, we have to give up this one due to linux_mmap
2223 	 * changes.
2224 	 *
2225 	 * http://lists.freebsd.org/pipermail/freebsd-emulation/2007-June/003698.html
2226 	 *
2227 	 */
2228 #ifdef SV_ABI_LINUX
2229 	if ((nprot & PROT_EXEC) && (dsp_mmap_allow_prot_exec < 0 ||
2230 	    (dsp_mmap_allow_prot_exec == 0 &&
2231 	    SV_CURPROC_ABI() != SV_ABI_LINUX)))
2232 #else
2233 	if ((nprot & PROT_EXEC) && dsp_mmap_allow_prot_exec < 1)
2234 #endif
2235 		return (EINVAL);
2236 
2237 	/*
2238 	 * PROT_READ (alone) selects the input buffer.
2239 	 * PROT_WRITE (alone) selects the output buffer.
2240 	 * PROT_WRITE|PROT_READ together select the output buffer.
2241 	 */
2242 	if ((nprot & (PROT_READ | PROT_WRITE)) == 0)
2243 		return (EINVAL);
2244 
2245 	d = dsp_get_info(i_dev);
2246 	if (!DSP_REGISTERED(d, i_dev))
2247 		return (EINVAL);
2248 
2249 	PCM_GIANT_ENTER(d);
2250 
2251 	getchns(i_dev, &rdch, &wrch, SD_F_PRIO_RD | SD_F_PRIO_WR);
2252 
2253 	c = ((nprot & PROT_WRITE) != 0) ? wrch : rdch;
2254 	if (c == NULL || (c->flags & CHN_F_MMAP_INVALID) ||
2255 	    (*offset  + size) > sndbuf_getsize(c->bufsoft) ||
2256 	    (wrch != NULL && (wrch->flags & CHN_F_MMAP_INVALID)) ||
2257 	    (rdch != NULL && (rdch->flags & CHN_F_MMAP_INVALID))) {
2258 		relchns(i_dev, rdch, wrch, SD_F_PRIO_RD | SD_F_PRIO_WR);
2259 		PCM_GIANT_EXIT(d);
2260 		return (EINVAL);
2261 	}
2262 
2263 	if (wrch != NULL)
2264 		wrch->flags |= CHN_F_MMAP;
2265 	if (rdch != NULL)
2266 		rdch->flags |= CHN_F_MMAP;
2267 
2268 	*offset = (uintptr_t)sndbuf_getbufofs(c->bufsoft, *offset);
2269 	relchns(i_dev, rdch, wrch, SD_F_PRIO_RD | SD_F_PRIO_WR);
2270 	*object = vm_pager_allocate(OBJT_DEVICE, i_dev,
2271 	    size, nprot, *offset, curthread->td_ucred);
2272 
2273 	PCM_GIANT_LEAVE(d);
2274 
2275 	if (*object == NULL)
2276 		 return (EINVAL);
2277 	return (0);
2278 }
2279 
2280 /* So much for dev_stdclone() */
2281 static int
2282 dsp_stdclone(char *name, char *namep, char *sep, int use_sep, int *u, int *c)
2283 {
2284 	size_t len;
2285 
2286 	len = strlen(namep);
2287 
2288 	if (bcmp(name, namep, len) != 0)
2289 		return (ENODEV);
2290 
2291 	name += len;
2292 
2293 	if (isdigit(*name) == 0)
2294 		return (ENODEV);
2295 
2296 	len = strlen(sep);
2297 
2298 	if (*name == '0' && !(name[1] == '\0' || bcmp(name + 1, sep, len) == 0))
2299 		return (ENODEV);
2300 
2301 	for (*u = 0; isdigit(*name) != 0; name++) {
2302 		*u *= 10;
2303 		*u += *name - '0';
2304 		if (*u > dsp_umax)
2305 			return (ENODEV);
2306 	}
2307 
2308 	if (*name == '\0')
2309 		return ((use_sep == 0) ? 0 : ENODEV);
2310 
2311 	if (bcmp(name, sep, len) != 0 || isdigit(name[len]) == 0)
2312 		return (ENODEV);
2313 
2314 	name += len;
2315 
2316 	if (*name == '0' && name[1] != '\0')
2317 		return (ENODEV);
2318 
2319 	for (*c = 0; isdigit(*name) != 0; name++) {
2320 		*c *= 10;
2321 		*c += *name - '0';
2322 		if (*c > dsp_cmax)
2323 			return (ENODEV);
2324 	}
2325 
2326 	if (*name != '\0')
2327 		return (ENODEV);
2328 
2329 	return (0);
2330 }
2331 
2332 static void
2333 dsp_clone(void *arg,
2334     struct ucred *cred,
2335     char *name, int namelen, struct cdev **dev)
2336 {
2337 	struct snddev_info *d;
2338 	struct snd_clone_entry *ce;
2339 	struct pcm_channel *c;
2340 	int i, unit, udcmask, cunit, devtype, devhw, devcmax, tumax;
2341 	char *devname, *devcmp, *devsep;
2342 
2343 	KASSERT(dsp_umax >= 0 && dsp_cmax >= 0, ("Uninitialized unit!"));
2344 
2345 	if (*dev != NULL)
2346 		return;
2347 
2348 	unit = -1;
2349 	cunit = -1;
2350 	devtype = -1;
2351 	devhw = 0;
2352 	devcmax = -1;
2353 	tumax = -1;
2354 	devname = NULL;
2355 	devsep = NULL;
2356 
2357 	for (i = 0; unit == -1 &&
2358 	    i < (sizeof(dsp_cdevs) / sizeof(dsp_cdevs[0])); i++) {
2359 		devtype = dsp_cdevs[i].type;
2360 		devcmp = dsp_cdevs[i].name;
2361 		devsep = dsp_cdevs[i].sep;
2362 		devname = dsp_cdevs[i].alias;
2363 		if (devname == NULL)
2364 			devname = devcmp;
2365 		devhw = dsp_cdevs[i].hw;
2366 		devcmax = dsp_cdevs[i].max - 1;
2367 		if (strcmp(name, devcmp) == 0) {
2368 			if (dsp_basename_clone != 0)
2369 				unit = snd_unit;
2370 		} else if (dsp_stdclone(name, devcmp, devsep,
2371 		    dsp_cdevs[i].use_sep, &unit, &cunit) != 0) {
2372 			unit = -1;
2373 			cunit = -1;
2374 		}
2375 	}
2376 
2377 	d = devclass_get_softc(pcm_devclass, unit);
2378 	if (!PCM_REGISTERED(d) || d->clones == NULL)
2379 		return;
2380 
2381 	/* XXX Need Giant magic entry ??? */
2382 
2383 	PCM_LOCK(d);
2384 	if (snd_clone_disabled(d->clones)) {
2385 		PCM_UNLOCK(d);
2386 		return;
2387 	}
2388 
2389 	PCM_WAIT(d);
2390 	PCM_ACQUIRE(d);
2391 	PCM_UNLOCK(d);
2392 
2393 	udcmask = snd_u2unit(unit) | snd_d2unit(devtype);
2394 
2395 	if (devhw != 0) {
2396 		KASSERT(devcmax <= dsp_cmax,
2397 		    ("overflow: devcmax=%d, dsp_cmax=%d", devcmax, dsp_cmax));
2398 		if (cunit > devcmax) {
2399 			PCM_RELEASE_QUICK(d);
2400 			return;
2401 		}
2402 		udcmask |= snd_c2unit(cunit);
2403 		CHN_FOREACH(c, d, channels.pcm) {
2404 			CHN_LOCK(c);
2405 			if (c->unit != udcmask) {
2406 				CHN_UNLOCK(c);
2407 				continue;
2408 			}
2409 			CHN_UNLOCK(c);
2410 			udcmask &= ~snd_c2unit(cunit);
2411 			/*
2412 			 * Temporarily increase clone maxunit to overcome
2413 			 * vchan flexibility.
2414 			 *
2415 			 * # sysctl dev.pcm.0.play.vchans=256
2416 			 * dev.pcm.0.play.vchans: 1 -> 256
2417 			 * # cat /dev/zero > /dev/dsp0.vp255 &
2418 			 * [1] 17296
2419 			 * # sysctl dev.pcm.0.play.vchans=0
2420 			 * dev.pcm.0.play.vchans: 256 -> 1
2421 			 * # fg
2422 			 * [1]  + running    cat /dev/zero > /dev/dsp0.vp255
2423 			 * ^C
2424 			 * # cat /dev/zero > /dev/dsp0.vp255
2425 			 * zsh: operation not supported: /dev/dsp0.vp255
2426 			 */
2427 			tumax = snd_clone_getmaxunit(d->clones);
2428 			if (cunit > tumax)
2429 				snd_clone_setmaxunit(d->clones, cunit);
2430 			else
2431 				tumax = -1;
2432 			goto dsp_clone_alloc;
2433 		}
2434 		/*
2435 		 * Ok, so we're requesting unallocated vchan, but still
2436 		 * within maximum vchan limit.
2437 		 */
2438 		if (((devtype == SND_DEV_DSPHW_VPLAY && d->pvchancount > 0) ||
2439 		    (devtype == SND_DEV_DSPHW_VREC && d->rvchancount > 0)) &&
2440 		    cunit < snd_maxautovchans) {
2441 			udcmask &= ~snd_c2unit(cunit);
2442 			tumax = snd_clone_getmaxunit(d->clones);
2443 			if (cunit > tumax)
2444 				snd_clone_setmaxunit(d->clones, cunit);
2445 			else
2446 				tumax = -1;
2447 			goto dsp_clone_alloc;
2448 		}
2449 		PCM_RELEASE_QUICK(d);
2450 		return;
2451 	}
2452 
2453 dsp_clone_alloc:
2454 	ce = snd_clone_alloc(d->clones, dev, &cunit, udcmask);
2455 	if (tumax != -1)
2456 		snd_clone_setmaxunit(d->clones, tumax);
2457 	if (ce != NULL) {
2458 		udcmask |= snd_c2unit(cunit);
2459 		*dev = make_dev(&dsp_cdevsw, PCMMINOR(udcmask),
2460 		    UID_ROOT, GID_WHEEL, 0666, "%s%d%s%d",
2461 		    devname, unit, devsep, cunit);
2462 		snd_clone_register(ce, *dev);
2463 	}
2464 
2465 	PCM_RELEASE_QUICK(d);
2466 
2467 	if (*dev != NULL)
2468 		dev_ref(*dev);
2469 }
2470 
2471 static void
2472 dsp_sysinit(void *p)
2473 {
2474 	if (dsp_ehtag != NULL)
2475 		return;
2476 	/* initialize unit numbering */
2477 	snd_unit_init();
2478 	dsp_umax = PCMMAXUNIT;
2479 	dsp_cmax = PCMMAXCHAN;
2480 	dsp_ehtag = EVENTHANDLER_REGISTER(dev_clone, dsp_clone, 0, 1000);
2481 }
2482 
2483 static void
2484 dsp_sysuninit(void *p)
2485 {
2486 	if (dsp_ehtag == NULL)
2487 		return;
2488 	EVENTHANDLER_DEREGISTER(dev_clone, dsp_ehtag);
2489 	dsp_ehtag = NULL;
2490 }
2491 
2492 SYSINIT(dsp_sysinit, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, dsp_sysinit, NULL);
2493 SYSUNINIT(dsp_sysuninit, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, dsp_sysuninit, NULL);
2494 
2495 char *
2496 dsp_unit2name(char *buf, size_t len, int unit)
2497 {
2498 	int i, dtype;
2499 
2500 	KASSERT(buf != NULL && len != 0,
2501 	    ("bogus buf=%p len=%ju", buf, (uintmax_t)len));
2502 
2503 	dtype = snd_unit2d(unit);
2504 
2505 	for (i = 0; i < (sizeof(dsp_cdevs) / sizeof(dsp_cdevs[0])); i++) {
2506 		if (dtype != dsp_cdevs[i].type || dsp_cdevs[i].alias != NULL)
2507 			continue;
2508 		snprintf(buf, len, "%s%d%s%d", dsp_cdevs[i].name,
2509 		    snd_unit2u(unit), dsp_cdevs[i].sep, snd_unit2c(unit));
2510 		return (buf);
2511 	}
2512 
2513 	return (NULL);
2514 }
2515 
2516 /**
2517  * @brief Handler for SNDCTL_AUDIOINFO.
2518  *
2519  * Gathers information about the audio device specified in ai->dev.  If
2520  * ai->dev == -1, then this function gathers information about the current
2521  * device.  If the call comes in on a non-audio device and ai->dev == -1,
2522  * return EINVAL.
2523  *
2524  * This routine is supposed to go practically straight to the hardware,
2525  * getting capabilities directly from the sound card driver, side-stepping
2526  * the intermediate channel interface.
2527  *
2528  * Note, however, that the usefulness of this command is significantly
2529  * decreased when requesting info about any device other than the one serving
2530  * the request. While each snddev_channel refers to a specific device node,
2531  * the converse is *not* true.  Currently, when a sound device node is opened,
2532  * the sound subsystem scans for an available audio channel (or channels, if
2533  * opened in read+write) and then assigns them to the si_drv[12] private
2534  * data fields.  As a result, any information returned linking a channel to
2535  * a specific character device isn't necessarily accurate.
2536  *
2537  * @note
2538  * Calling threads must not hold any snddev_info or pcm_channel locks.
2539  *
2540  * @param dev		device on which the ioctl was issued
2541  * @param ai		ioctl request data container
2542  *
2543  * @retval 0		success
2544  * @retval EINVAL	ai->dev specifies an invalid device
2545  *
2546  * @todo Verify correctness of Doxygen tags.  ;)
2547  */
2548 int
2549 dsp_oss_audioinfo(struct cdev *i_dev, oss_audioinfo *ai)
2550 {
2551 	struct pcmchan_caps *caps;
2552 	struct pcm_channel *ch;
2553 	struct snddev_info *d;
2554 	uint32_t fmts;
2555 	int i, nchan, *rates, minch, maxch;
2556 	char *devname, buf[CHN_NAMELEN];
2557 
2558 	/*
2559 	 * If probing the device that received the ioctl, make sure it's a
2560 	 * DSP device.  (Users may use this ioctl with /dev/mixer and
2561 	 * /dev/midi.)
2562 	 */
2563 	if (ai->dev == -1 && i_dev->si_devsw != &dsp_cdevsw)
2564 		return (EINVAL);
2565 
2566 	ch = NULL;
2567 	devname = NULL;
2568 	nchan = 0;
2569 	bzero(buf, sizeof(buf));
2570 
2571 	/*
2572 	 * Search for the requested audio device (channel).  Start by
2573 	 * iterating over pcm devices.
2574 	 */
2575 	for (i = 0; pcm_devclass != NULL &&
2576 	    i < devclass_get_maxunit(pcm_devclass); i++) {
2577 		d = devclass_get_softc(pcm_devclass, i);
2578 		if (!PCM_REGISTERED(d))
2579 			continue;
2580 
2581 		/* XXX Need Giant magic entry ??? */
2582 
2583 		/* See the note in function docblock */
2584 		PCM_UNLOCKASSERT(d);
2585 		PCM_LOCK(d);
2586 
2587 		CHN_FOREACH(ch, d, channels.pcm) {
2588 			CHN_UNLOCKASSERT(ch);
2589 			CHN_LOCK(ch);
2590 			if (ai->dev == -1) {
2591 				if (DSP_REGISTERED(d, i_dev) &&
2592 				    (ch == PCM_RDCH(i_dev) ||	/* record ch */
2593 				    ch == PCM_WRCH(i_dev))) {	/* playback ch */
2594 					devname = dsp_unit2name(buf,
2595 					    sizeof(buf), ch->unit);
2596 				}
2597 			} else if (ai->dev == nchan) {
2598 				devname = dsp_unit2name(buf, sizeof(buf),
2599 				    ch->unit);
2600 			}
2601 			if (devname != NULL)
2602 				break;
2603 			CHN_UNLOCK(ch);
2604 			++nchan;
2605 		}
2606 
2607 		if (devname != NULL) {
2608 			/*
2609 			 * At this point, the following synchronization stuff
2610 			 * has happened:
2611 			 * - a specific PCM device is locked.
2612 			 * - a specific audio channel has been locked, so be
2613 			 *   sure to unlock when exiting;
2614 			 */
2615 
2616 			caps = chn_getcaps(ch);
2617 
2618 			/*
2619 			 * With all handles collected, zero out the user's
2620 			 * container and begin filling in its fields.
2621 			 */
2622 			bzero((void *)ai, sizeof(oss_audioinfo));
2623 
2624 			ai->dev = nchan;
2625 			strlcpy(ai->name, ch->name,  sizeof(ai->name));
2626 
2627 			if ((ch->flags & CHN_F_BUSY) == 0)
2628 				ai->busy = 0;
2629 			else
2630 				ai->busy = (ch->direction == PCMDIR_PLAY) ? OPEN_WRITE : OPEN_READ;
2631 
2632 			/**
2633 			 * @note
2634 			 * @c cmd - OSSv4 docs: "Only supported under Linux at
2635 			 *    this moment." Cop-out, I know, but I'll save
2636 			 *    running around in the process table for later.
2637 			 *    Is there a risk of leaking information?
2638 			 */
2639 			ai->pid = ch->pid;
2640 
2641 			/*
2642 			 * These flags stolen from SNDCTL_DSP_GETCAPS handler.
2643 			 * Note, however, that a single channel operates in
2644 			 * only one direction, so PCM_CAP_DUPLEX is out.
2645 			 */
2646 			/**
2647 			 * @todo @c SNDCTL_AUDIOINFO::caps - Make drivers keep
2648 			 *       these in pcmchan::caps?
2649 			 */
2650 			ai->caps = PCM_CAP_REALTIME | PCM_CAP_MMAP | PCM_CAP_TRIGGER |
2651 			    ((ch->direction == PCMDIR_PLAY) ? PCM_CAP_OUTPUT : PCM_CAP_INPUT);
2652 
2653 			/*
2654 			 * Collect formats supported @b natively by the
2655 			 * device.  Also determine min/max channels.  (I.e.,
2656 			 * mono, stereo, or both?)
2657 			 *
2658 			 * If any channel is stereo, maxch = 2;
2659 			 * if all channels are stereo, minch = 2, too;
2660 			 * if any channel is mono, minch = 1;
2661 			 * and if all channels are mono, maxch = 1.
2662 			 */
2663 			minch = 0;
2664 			maxch = 0;
2665 			fmts = 0;
2666 			for (i = 0; caps->fmtlist[i]; i++) {
2667 				fmts |= caps->fmtlist[i];
2668 				if (AFMT_CHANNEL(caps->fmtlist[i]) > 1) {
2669 					minch = (minch == 0) ? 2 : minch;
2670 					maxch = 2;
2671 				} else {
2672 					minch = 1;
2673 					maxch = (maxch == 0) ? 1 : maxch;
2674 				}
2675 			}
2676 
2677 			if (ch->direction == PCMDIR_PLAY)
2678 				ai->oformats = fmts;
2679 			else
2680 				ai->iformats = fmts;
2681 
2682 			/**
2683 			 * @note
2684 			 * @c magic - OSSv4 docs: "Reserved for internal use
2685 			 *    by OSS."
2686 			 *
2687 			 * @par
2688 			 * @c card_number - OSSv4 docs: "Number of the sound
2689 			 *    card where this device belongs or -1 if this
2690 			 *    information is not available.  Applications
2691 			 *    should normally not use this field for any
2692 			 *    purpose."
2693 			 */
2694 			ai->card_number = -1;
2695 			/**
2696 			 * @todo @c song_name - depends first on
2697 			 *          SNDCTL_[GS]ETSONG @todo @c label - depends
2698 			 *          on SNDCTL_[GS]ETLABEL
2699 			 * @todo @c port_number - routing information?
2700 			 */
2701 			ai->port_number = -1;
2702 			ai->mixer_dev = (d->mixer_dev != NULL) ? PCMUNIT(d->mixer_dev) : -1;
2703 			/**
2704 			 * @note
2705 			 * @c real_device - OSSv4 docs:  "Obsolete."
2706 			 */
2707 			ai->real_device = -1;
2708 			strlcpy(ai->devnode, "/dev/", sizeof(ai->devnode));
2709 			strlcat(ai->devnode, devname, sizeof(ai->devnode));
2710 			ai->enabled = device_is_attached(d->dev) ? 1 : 0;
2711 			/**
2712 			 * @note
2713 			 * @c flags - OSSv4 docs: "Reserved for future use."
2714 			 *
2715 			 * @note
2716 			 * @c binding - OSSv4 docs: "Reserved for future use."
2717 			 *
2718 			 * @todo @c handle - haven't decided how to generate
2719 			 *       this yet; bus, vendor, device IDs?
2720 			 */
2721 			ai->min_rate = caps->minspeed;
2722 			ai->max_rate = caps->maxspeed;
2723 
2724 			ai->min_channels = minch;
2725 			ai->max_channels = maxch;
2726 
2727 			ai->nrates = chn_getrates(ch, &rates);
2728 			if (ai->nrates > OSS_MAX_SAMPLE_RATES)
2729 				ai->nrates = OSS_MAX_SAMPLE_RATES;
2730 
2731 			for (i = 0; i < ai->nrates; i++)
2732 				ai->rates[i] = rates[i];
2733 
2734 			ai->next_play_engine = 0;
2735 			ai->next_rec_engine = 0;
2736 
2737 			CHN_UNLOCK(ch);
2738 		}
2739 
2740 		PCM_UNLOCK(d);
2741 
2742 		if (devname != NULL)
2743 			return (0);
2744 	}
2745 
2746 	/* Exhausted the search -- nothing is locked, so return. */
2747 	return (EINVAL);
2748 }
2749 
2750 /**
2751  * @brief Assigns a PCM channel to a sync group.
2752  *
2753  * Sync groups are used to enable audio operations on multiple devices
2754  * simultaneously.  They may be used with any number of devices and may
2755  * span across applications.  Devices are added to groups with
2756  * the SNDCTL_DSP_SYNCGROUP ioctl, and operations are triggered with the
2757  * SNDCTL_DSP_SYNCSTART ioctl.
2758  *
2759  * If the @c id field of the @c group parameter is set to zero, then a new
2760  * sync group is created.  Otherwise, wrch and rdch (if set) are added to
2761  * the group specified.
2762  *
2763  * @todo As far as memory allocation, should we assume that things are
2764  * 	 okay and allocate with M_WAITOK before acquiring channel locks,
2765  * 	 freeing later if not?
2766  *
2767  * @param wrch	output channel associated w/ device (if any)
2768  * @param rdch	input channel associated w/ device (if any)
2769  * @param group Sync group parameters
2770  *
2771  * @retval 0		success
2772  * @retval non-zero	error to be propagated upstream
2773  */
2774 static int
2775 dsp_oss_syncgroup(struct pcm_channel *wrch, struct pcm_channel *rdch, oss_syncgroup *group)
2776 {
2777 	struct pcmchan_syncmember *smrd, *smwr;
2778 	struct pcmchan_syncgroup *sg;
2779 	int ret, sg_ids[3];
2780 
2781 	smrd = NULL;
2782 	smwr = NULL;
2783 	sg = NULL;
2784 	ret = 0;
2785 
2786 	/*
2787 	 * Free_unr() may sleep, so store released syncgroup IDs until after
2788 	 * all locks are released.
2789 	 */
2790 	sg_ids[0] = sg_ids[1] = sg_ids[2] = 0;
2791 
2792 	PCM_SG_LOCK();
2793 
2794 	/*
2795 	 * - Insert channel(s) into group's member list.
2796 	 * - Set CHN_F_NOTRIGGER on channel(s).
2797 	 * - Stop channel(s).
2798 	 */
2799 
2800 	/*
2801 	 * If device's channels are already mapped to a group, unmap them.
2802 	 */
2803 	if (wrch) {
2804 		CHN_LOCK(wrch);
2805 		sg_ids[0] = chn_syncdestroy(wrch);
2806 	}
2807 
2808 	if (rdch) {
2809 		CHN_LOCK(rdch);
2810 		sg_ids[1] = chn_syncdestroy(rdch);
2811 	}
2812 
2813 	/*
2814 	 * Verify that mode matches character device properites.
2815 	 *  - Bail if PCM_ENABLE_OUTPUT && wrch == NULL.
2816 	 *  - Bail if PCM_ENABLE_INPUT && rdch == NULL.
2817 	 */
2818 	if (((wrch == NULL) && (group->mode & PCM_ENABLE_OUTPUT)) ||
2819 	    ((rdch == NULL) && (group->mode & PCM_ENABLE_INPUT))) {
2820 		ret = EINVAL;
2821 		goto out;
2822 	}
2823 
2824 	/*
2825 	 * An id of zero indicates the user wants to create a new
2826 	 * syncgroup.
2827 	 */
2828 	if (group->id == 0) {
2829 		sg = (struct pcmchan_syncgroup *)malloc(sizeof(*sg), M_DEVBUF, M_NOWAIT);
2830 		if (sg != NULL) {
2831 			SLIST_INIT(&sg->members);
2832 			sg->id = alloc_unr(pcmsg_unrhdr);
2833 
2834 			group->id = sg->id;
2835 			SLIST_INSERT_HEAD(&snd_pcm_syncgroups, sg, link);
2836 		} else
2837 			ret = ENOMEM;
2838 	} else {
2839 		SLIST_FOREACH(sg, &snd_pcm_syncgroups, link) {
2840 			if (sg->id == group->id)
2841 				break;
2842 		}
2843 		if (sg == NULL)
2844 			ret = EINVAL;
2845 	}
2846 
2847 	/* Couldn't create or find a syncgroup.  Fail. */
2848 	if (sg == NULL)
2849 		goto out;
2850 
2851 	/*
2852 	 * Allocate a syncmember, assign it and a channel together, and
2853 	 * insert into syncgroup.
2854 	 */
2855 	if (group->mode & PCM_ENABLE_INPUT) {
2856 		smrd = (struct pcmchan_syncmember *)malloc(sizeof(*smrd), M_DEVBUF, M_NOWAIT);
2857 		if (smrd == NULL) {
2858 			ret = ENOMEM;
2859 			goto out;
2860 		}
2861 
2862 		SLIST_INSERT_HEAD(&sg->members, smrd, link);
2863 		smrd->parent = sg;
2864 		smrd->ch = rdch;
2865 
2866 		chn_abort(rdch);
2867 		rdch->flags |= CHN_F_NOTRIGGER;
2868 		rdch->sm = smrd;
2869 	}
2870 
2871 	if (group->mode & PCM_ENABLE_OUTPUT) {
2872 		smwr = (struct pcmchan_syncmember *)malloc(sizeof(*smwr), M_DEVBUF, M_NOWAIT);
2873 		if (smwr == NULL) {
2874 			ret = ENOMEM;
2875 			goto out;
2876 		}
2877 
2878 		SLIST_INSERT_HEAD(&sg->members, smwr, link);
2879 		smwr->parent = sg;
2880 		smwr->ch = wrch;
2881 
2882 		chn_abort(wrch);
2883 		wrch->flags |= CHN_F_NOTRIGGER;
2884 		wrch->sm = smwr;
2885 	}
2886 
2887 
2888 out:
2889 	if (ret != 0) {
2890 		if (smrd != NULL)
2891 			free(smrd, M_DEVBUF);
2892 		if ((sg != NULL) && SLIST_EMPTY(&sg->members)) {
2893 			sg_ids[2] = sg->id;
2894 			SLIST_REMOVE(&snd_pcm_syncgroups, sg, pcmchan_syncgroup, link);
2895 			free(sg, M_DEVBUF);
2896 		}
2897 
2898 		if (wrch)
2899 			wrch->sm = NULL;
2900 		if (rdch)
2901 			rdch->sm = NULL;
2902 	}
2903 
2904 	if (wrch)
2905 		CHN_UNLOCK(wrch);
2906 	if (rdch)
2907 		CHN_UNLOCK(rdch);
2908 
2909 	PCM_SG_UNLOCK();
2910 
2911 	if (sg_ids[0])
2912 		free_unr(pcmsg_unrhdr, sg_ids[0]);
2913 	if (sg_ids[1])
2914 		free_unr(pcmsg_unrhdr, sg_ids[1]);
2915 	if (sg_ids[2])
2916 		free_unr(pcmsg_unrhdr, sg_ids[2]);
2917 
2918 	return (ret);
2919 }
2920 
2921 /**
2922  * @brief Launch a sync group into action
2923  *
2924  * Sync groups are established via SNDCTL_DSP_SYNCGROUP.  This function
2925  * iterates over all members, triggering them along the way.
2926  *
2927  * @note Caller must not hold any channel locks.
2928  *
2929  * @param sg_id	sync group identifier
2930  *
2931  * @retval 0	success
2932  * @retval non-zero	error worthy of propagating upstream to user
2933  */
2934 static int
2935 dsp_oss_syncstart(int sg_id)
2936 {
2937 	struct pcmchan_syncmember *sm, *sm_tmp;
2938 	struct pcmchan_syncgroup *sg;
2939 	struct pcm_channel *c;
2940 	int ret, needlocks;
2941 
2942 	/* Get the synclists lock */
2943 	PCM_SG_LOCK();
2944 
2945 	do {
2946 		ret = 0;
2947 		needlocks = 0;
2948 
2949 		/* Search for syncgroup by ID */
2950 		SLIST_FOREACH(sg, &snd_pcm_syncgroups, link) {
2951 			if (sg->id == sg_id)
2952 				break;
2953 		}
2954 
2955 		/* Return EINVAL if not found */
2956 		if (sg == NULL) {
2957 			ret = EINVAL;
2958 			break;
2959 		}
2960 
2961 		/* Any removals resulting in an empty group should've handled this */
2962 		KASSERT(!SLIST_EMPTY(&sg->members), ("found empty syncgroup"));
2963 
2964 		/*
2965 		 * Attempt to lock all member channels - if any are already
2966 		 * locked, unlock those acquired, sleep for a bit, and try
2967 		 * again.
2968 		 */
2969 		SLIST_FOREACH(sm, &sg->members, link) {
2970 			if (CHN_TRYLOCK(sm->ch) == 0) {
2971 				int timo = hz * 5/1000;
2972 				if (timo < 1)
2973 					timo = 1;
2974 
2975 				/* Release all locked channels so far, retry */
2976 				SLIST_FOREACH(sm_tmp, &sg->members, link) {
2977 					/* sm is the member already locked */
2978 					if (sm == sm_tmp)
2979 						break;
2980 					CHN_UNLOCK(sm_tmp->ch);
2981 				}
2982 
2983 				/** @todo Is PRIBIO correct/ */
2984 				ret = msleep(sm, &snd_pcm_syncgroups_mtx,
2985 				    PRIBIO | PCATCH, "pcmsg", timo);
2986 				if (ret == EINTR || ret == ERESTART)
2987 					break;
2988 
2989 				needlocks = 1;
2990 				ret = 0; /* Assumes ret == EAGAIN... */
2991 			}
2992 		}
2993 	} while (needlocks && ret == 0);
2994 
2995 	/* Proceed only if no errors encountered. */
2996 	if (ret == 0) {
2997 		/* Launch channels */
2998 		while ((sm = SLIST_FIRST(&sg->members)) != NULL) {
2999 			SLIST_REMOVE_HEAD(&sg->members, link);
3000 
3001 			c = sm->ch;
3002 			c->sm = NULL;
3003 			chn_start(c, 1);
3004 			c->flags &= ~CHN_F_NOTRIGGER;
3005 			CHN_UNLOCK(c);
3006 
3007 			free(sm, M_DEVBUF);
3008 		}
3009 
3010 		SLIST_REMOVE(&snd_pcm_syncgroups, sg, pcmchan_syncgroup, link);
3011 		free(sg, M_DEVBUF);
3012 	}
3013 
3014 	PCM_SG_UNLOCK();
3015 
3016 	/*
3017 	 * Free_unr() may sleep, so be sure to give up the syncgroup lock
3018 	 * first.
3019 	 */
3020 	if (ret == 0)
3021 		free_unr(pcmsg_unrhdr, sg_id);
3022 
3023 	return (ret);
3024 }
3025 
3026 /**
3027  * @brief Handler for SNDCTL_DSP_POLICY
3028  *
3029  * The SNDCTL_DSP_POLICY ioctl is a simpler interface to control fragment
3030  * size and count like with SNDCTL_DSP_SETFRAGMENT.  Instead of the user
3031  * specifying those two parameters, s/he simply selects a number from 0..10
3032  * which corresponds to a buffer size.  Smaller numbers request smaller
3033  * buffers with lower latencies (at greater overhead from more frequent
3034  * interrupts), while greater numbers behave in the opposite manner.
3035  *
3036  * The 4Front spec states that a value of 5 should be the default.  However,
3037  * this implementation deviates slightly by using a linear scale without
3038  * consulting drivers.  I.e., even though drivers may have different default
3039  * buffer sizes, a policy argument of 5 will have the same result across
3040  * all drivers.
3041  *
3042  * See http://manuals.opensound.com/developer/SNDCTL_DSP_POLICY.html for
3043  * more information.
3044  *
3045  * @todo When SNDCTL_DSP_COOKEDMODE is supported, it'll be necessary to
3046  * 	 work with hardware drivers directly.
3047  *
3048  * @note PCM channel arguments must not be locked by caller.
3049  *
3050  * @param wrch	Pointer to opened playback channel (optional; may be NULL)
3051  * @param rdch	" recording channel (optional; may be NULL)
3052  * @param policy Integer from [0:10]
3053  *
3054  * @retval 0	constant (for now)
3055  */
3056 static int
3057 dsp_oss_policy(struct pcm_channel *wrch, struct pcm_channel *rdch, int policy)
3058 {
3059 	int ret;
3060 
3061 	if (policy < CHN_POLICY_MIN || policy > CHN_POLICY_MAX)
3062 		return (EIO);
3063 
3064 	/* Default: success */
3065 	ret = 0;
3066 
3067 	if (rdch) {
3068 		CHN_LOCK(rdch);
3069 		ret = chn_setlatency(rdch, policy);
3070 		CHN_UNLOCK(rdch);
3071 	}
3072 
3073 	if (wrch && ret == 0) {
3074 		CHN_LOCK(wrch);
3075 		ret = chn_setlatency(wrch, policy);
3076 		CHN_UNLOCK(wrch);
3077 	}
3078 
3079 	if (ret)
3080 		ret = EIO;
3081 
3082 	return (ret);
3083 }
3084 
3085 /**
3086  * @brief Enable or disable "cooked" mode
3087  *
3088  * This is a handler for @c SNDCTL_DSP_COOKEDMODE.  When in cooked mode, which
3089  * is the default, the sound system handles rate and format conversions
3090  * automatically (ex: user writing 11025Hz/8 bit/unsigned but card only
3091  * operates with 44100Hz/16bit/signed samples).
3092  *
3093  * Disabling cooked mode is intended for applications wanting to mmap()
3094  * a sound card's buffer space directly, bypassing the FreeBSD 2-stage
3095  * feeder architecture, presumably to gain as much control over audio
3096  * hardware as possible.
3097  *
3098  * See @c http://manuals.opensound.com/developer/SNDCTL_DSP_COOKEDMODE.html
3099  * for more details.
3100  *
3101  * @param wrch		playback channel (optional; may be NULL)
3102  * @param rdch		recording channel (optional; may be NULL)
3103  * @param enabled	0 = raw mode, 1 = cooked mode
3104  *
3105  * @retval EINVAL	Operation not yet supported.
3106  */
3107 static int
3108 dsp_oss_cookedmode(struct pcm_channel *wrch, struct pcm_channel *rdch, int enabled)
3109 {
3110 
3111 	/*
3112 	 * XXX I just don't get it. Why don't they call it
3113 	 * "BITPERFECT" ~ SNDCTL_DSP_BITPERFECT !?!?.
3114 	 * This is just plain so confusing, incoherent,
3115 	 * <insert any non-printable characters here>.
3116 	 */
3117 	if (!(enabled == 1 || enabled == 0))
3118 		return (EINVAL);
3119 
3120 	/*
3121 	 * I won't give in. I'm inverting its logic here and now.
3122 	 * Brag all you want, but "BITPERFECT" should be the better
3123 	 * term here.
3124 	 */
3125 	enabled ^= 0x00000001;
3126 
3127 	if (wrch != NULL) {
3128 		CHN_LOCK(wrch);
3129 		wrch->flags &= ~CHN_F_BITPERFECT;
3130 		wrch->flags |= (enabled != 0) ? CHN_F_BITPERFECT : 0x00000000;
3131 		CHN_UNLOCK(wrch);
3132 	}
3133 
3134 	if (rdch != NULL) {
3135 		CHN_LOCK(rdch);
3136 		rdch->flags &= ~CHN_F_BITPERFECT;
3137 		rdch->flags |= (enabled != 0) ? CHN_F_BITPERFECT : 0x00000000;
3138 		CHN_UNLOCK(rdch);
3139 	}
3140 
3141 	return (0);
3142 }
3143 
3144 /**
3145  * @brief Retrieve channel interleaving order
3146  *
3147  * This is the handler for @c SNDCTL_DSP_GET_CHNORDER.
3148  *
3149  * See @c http://manuals.opensound.com/developer/SNDCTL_DSP_GET_CHNORDER.html
3150  * for more details.
3151  *
3152  * @note As the ioctl definition is still under construction, FreeBSD
3153  * 	 does not currently support SNDCTL_DSP_GET_CHNORDER.
3154  *
3155  * @param wrch	playback channel (optional; may be NULL)
3156  * @param rdch	recording channel (optional; may be NULL)
3157  * @param map	channel map (result will be stored there)
3158  *
3159  * @retval EINVAL	Operation not yet supported.
3160  */
3161 static int
3162 dsp_oss_getchnorder(struct pcm_channel *wrch, struct pcm_channel *rdch, unsigned long long *map)
3163 {
3164 	struct pcm_channel *ch;
3165 	int ret;
3166 
3167 	ch = (wrch != NULL) ? wrch : rdch;
3168 	if (ch != NULL) {
3169 		CHN_LOCK(ch);
3170 		ret = chn_oss_getorder(ch, map);
3171 		CHN_UNLOCK(ch);
3172 	} else
3173 		ret = EINVAL;
3174 
3175 	return (ret);
3176 }
3177 
3178 /**
3179  * @brief Specify channel interleaving order
3180  *
3181  * This is the handler for @c SNDCTL_DSP_SET_CHNORDER.
3182  *
3183  * @note As the ioctl definition is still under construction, FreeBSD
3184  * 	 does not currently support @c SNDCTL_DSP_SET_CHNORDER.
3185  *
3186  * @param wrch	playback channel (optional; may be NULL)
3187  * @param rdch	recording channel (optional; may be NULL)
3188  * @param map	channel map
3189  *
3190  * @retval EINVAL	Operation not yet supported.
3191  */
3192 static int
3193 dsp_oss_setchnorder(struct pcm_channel *wrch, struct pcm_channel *rdch, unsigned long long *map)
3194 {
3195 	int ret;
3196 
3197 	ret = 0;
3198 
3199 	if (wrch != NULL) {
3200 		CHN_LOCK(wrch);
3201 		ret = chn_oss_setorder(wrch, map);
3202 		CHN_UNLOCK(wrch);
3203 	}
3204 
3205 	if (ret == 0 && rdch != NULL) {
3206 		CHN_LOCK(rdch);
3207 		ret = chn_oss_setorder(rdch, map);
3208 		CHN_UNLOCK(rdch);
3209 	}
3210 
3211 	return (ret);
3212 }
3213 
3214 static int
3215 dsp_oss_getchannelmask(struct pcm_channel *wrch, struct pcm_channel *rdch,
3216     int *mask)
3217 {
3218 	struct pcm_channel *ch;
3219 	uint32_t chnmask;
3220 	int ret;
3221 
3222 	chnmask = 0;
3223 	ch = (wrch != NULL) ? wrch : rdch;
3224 
3225 	if (ch != NULL) {
3226 		CHN_LOCK(ch);
3227 		ret = chn_oss_getmask(ch, &chnmask);
3228 		CHN_UNLOCK(ch);
3229 	} else
3230 		ret = EINVAL;
3231 
3232 	if (ret == 0)
3233 		*mask = chnmask;
3234 
3235 	return (ret);
3236 }
3237 
3238 #ifdef OSSV4_EXPERIMENT
3239 /**
3240  * @brief Retrieve an audio device's label
3241  *
3242  * This is a handler for the @c SNDCTL_GETLABEL ioctl.
3243  *
3244  * See @c http://manuals.opensound.com/developer/SNDCTL_GETLABEL.html
3245  * for more details.
3246  *
3247  * From Hannu@4Front:  "For example ossxmix (just like some HW mixer
3248  * consoles) can show variable "labels" for certain controls. By default
3249  * the application name (say quake) is shown as the label but
3250  * applications may change the labels themselves."
3251  *
3252  * @note As the ioctl definition is still under construction, FreeBSD
3253  * 	 does not currently support @c SNDCTL_GETLABEL.
3254  *
3255  * @param wrch	playback channel (optional; may be NULL)
3256  * @param rdch	recording channel (optional; may be NULL)
3257  * @param label	label gets copied here
3258  *
3259  * @retval EINVAL	Operation not yet supported.
3260  */
3261 static int
3262 dsp_oss_getlabel(struct pcm_channel *wrch, struct pcm_channel *rdch, oss_label_t *label)
3263 {
3264 	return (EINVAL);
3265 }
3266 
3267 /**
3268  * @brief Specify an audio device's label
3269  *
3270  * This is a handler for the @c SNDCTL_SETLABEL ioctl.  Please see the
3271  * comments for @c dsp_oss_getlabel immediately above.
3272  *
3273  * See @c http://manuals.opensound.com/developer/SNDCTL_GETLABEL.html
3274  * for more details.
3275  *
3276  * @note As the ioctl definition is still under construction, FreeBSD
3277  * 	 does not currently support SNDCTL_SETLABEL.
3278  *
3279  * @param wrch	playback channel (optional; may be NULL)
3280  * @param rdch	recording channel (optional; may be NULL)
3281  * @param label	label gets copied from here
3282  *
3283  * @retval EINVAL	Operation not yet supported.
3284  */
3285 static int
3286 dsp_oss_setlabel(struct pcm_channel *wrch, struct pcm_channel *rdch, oss_label_t *label)
3287 {
3288 	return (EINVAL);
3289 }
3290 
3291 /**
3292  * @brief Retrieve name of currently played song
3293  *
3294  * This is a handler for the @c SNDCTL_GETSONG ioctl.  Audio players could
3295  * tell the system the name of the currently playing song, which would be
3296  * visible in @c /dev/sndstat.
3297  *
3298  * See @c http://manuals.opensound.com/developer/SNDCTL_GETSONG.html
3299  * for more details.
3300  *
3301  * @note As the ioctl definition is still under construction, FreeBSD
3302  * 	 does not currently support SNDCTL_GETSONG.
3303  *
3304  * @param wrch	playback channel (optional; may be NULL)
3305  * @param rdch	recording channel (optional; may be NULL)
3306  * @param song	song name gets copied here
3307  *
3308  * @retval EINVAL	Operation not yet supported.
3309  */
3310 static int
3311 dsp_oss_getsong(struct pcm_channel *wrch, struct pcm_channel *rdch, oss_longname_t *song)
3312 {
3313 	return (EINVAL);
3314 }
3315 
3316 /**
3317  * @brief Retrieve name of currently played song
3318  *
3319  * This is a handler for the @c SNDCTL_SETSONG ioctl.  Audio players could
3320  * tell the system the name of the currently playing song, which would be
3321  * visible in @c /dev/sndstat.
3322  *
3323  * See @c http://manuals.opensound.com/developer/SNDCTL_SETSONG.html
3324  * for more details.
3325  *
3326  * @note As the ioctl definition is still under construction, FreeBSD
3327  * 	 does not currently support SNDCTL_SETSONG.
3328  *
3329  * @param wrch	playback channel (optional; may be NULL)
3330  * @param rdch	recording channel (optional; may be NULL)
3331  * @param song	song name gets copied from here
3332  *
3333  * @retval EINVAL	Operation not yet supported.
3334  */
3335 static int
3336 dsp_oss_setsong(struct pcm_channel *wrch, struct pcm_channel *rdch, oss_longname_t *song)
3337 {
3338 	return (EINVAL);
3339 }
3340 
3341 /**
3342  * @brief Rename a device
3343  *
3344  * This is a handler for the @c SNDCTL_SETNAME ioctl.
3345  *
3346  * See @c http://manuals.opensound.com/developer/SNDCTL_SETNAME.html for
3347  * more details.
3348  *
3349  * From Hannu@4Front:  "This call is used to change the device name
3350  * reported in /dev/sndstat and ossinfo. So instead of  using some generic
3351  * 'OSS loopback audio (MIDI) driver' the device may be given a meaningfull
3352  * name depending on the current context (for example 'OSS virtual wave table
3353  * synth' or 'VoIP link to London')."
3354  *
3355  * @note As the ioctl definition is still under construction, FreeBSD
3356  * 	 does not currently support SNDCTL_SETNAME.
3357  *
3358  * @param wrch	playback channel (optional; may be NULL)
3359  * @param rdch	recording channel (optional; may be NULL)
3360  * @param name	new device name gets copied from here
3361  *
3362  * @retval EINVAL	Operation not yet supported.
3363  */
3364 static int
3365 dsp_oss_setname(struct pcm_channel *wrch, struct pcm_channel *rdch, oss_longname_t *name)
3366 {
3367 	return (EINVAL);
3368 }
3369 #endif	/* !OSSV4_EXPERIMENT */
3370