xref: /freebsd/sys/dev/sound/pcm/sound.h (revision 5fcaf1329722d5565900aa61659495d81e0c9ae4)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2005-2009 Ariff Abdullah <ariff@FreeBSD.org>
5  * Copyright (c) 1999 Cameron Grant <cg@FreeBSD.org>
6  * Copyright (c) 1995 Hannu Savolainen
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 /*
32  * first, include kernel header files.
33  */
34 
35 #ifndef _OS_H_
36 #define _OS_H_
37 
38 #ifdef _KERNEL
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/eventhandler.h>
42 #include <sys/ioccom.h>
43 #include <sys/filio.h>
44 #include <sys/sockio.h>
45 #include <sys/fcntl.h>
46 #include <sys/selinfo.h>
47 #include <sys/proc.h>
48 #include <sys/kernel.h> /* for DATA_SET */
49 #include <sys/module.h>
50 #include <sys/conf.h>
51 #include <sys/file.h>
52 #include <sys/uio.h>
53 #include <sys/syslog.h>
54 #include <sys/errno.h>
55 #include <sys/malloc.h>
56 #include <sys/bus.h>
57 #include <machine/resource.h>
58 #include <machine/bus.h>
59 #include <sys/rman.h>
60 #include <sys/limits.h>
61 #include <sys/mman.h>
62 #include <sys/poll.h>
63 #include <sys/sbuf.h>
64 #include <sys/soundcard.h>
65 #include <sys/sndstat.h>
66 #include <sys/sysctl.h>
67 #include <sys/kobj.h>
68 #include <vm/vm.h>
69 #include <vm/pmap.h>
70 
71 #include <sys/lock.h>
72 #include <sys/mutex.h>
73 #include <sys/condvar.h>
74 
75 #ifndef KOBJMETHOD_END
76 #define KOBJMETHOD_END	{ NULL, NULL }
77 #endif
78 
79 struct pcm_channel;
80 struct pcm_feeder;
81 struct snd_dbuf;
82 struct snd_mixer;
83 
84 #include <dev/sound/pcm/buffer.h>
85 #include <dev/sound/pcm/matrix.h>
86 #include <dev/sound/pcm/matrix_map.h>
87 #include <dev/sound/pcm/channel.h>
88 #include <dev/sound/pcm/feeder.h>
89 #include <dev/sound/pcm/mixer.h>
90 #include <dev/sound/pcm/dsp.h>
91 
92 #define	PCM_SOFTC_SIZE	(sizeof(struct snddev_info))
93 
94 #define SND_STATUSLEN	64
95 
96 #define SOUND_MODVER	5
97 
98 #define SOUND_MINVER	SOUND_MODVER
99 #define SOUND_PREFVER	SOUND_MODVER
100 #define SOUND_MAXVER	SOUND_MODVER
101 
102 #define SND_MAXVCHANS		256
103 
104 #define SD_F_SIMPLEX		0x00000001
105 #define SD_F_AUTOVCHAN		0x00000002
106 #define SD_F_SOFTPCMVOL		0x00000004
107 #define SD_F_BUSY		0x00000008
108 #define SD_F_MPSAFE		0x00000010
109 #define SD_F_REGISTERED		0x00000020
110 #define SD_F_BITPERFECT		0x00000040
111 #define SD_F_VPC		0x00000080	/* volume-per-channel */
112 #define SD_F_EQ			0x00000100	/* EQ */
113 #define SD_F_EQ_ENABLED		0x00000200	/* EQ enabled */
114 #define SD_F_EQ_BYPASSED	0x00000400	/* EQ bypassed */
115 #define SD_F_EQ_PC		0x00000800	/* EQ per-channel */
116 
117 #define SD_F_EQ_DEFAULT		(SD_F_EQ | SD_F_EQ_ENABLED)
118 #define SD_F_EQ_MASK		(SD_F_EQ | SD_F_EQ_ENABLED |		\
119 				 SD_F_EQ_BYPASSED | SD_F_EQ_PC)
120 
121 #define SD_F_PRIO_RD		0x10000000
122 #define SD_F_PRIO_WR		0x20000000
123 
124 #define SD_F_BITS		"\020"					\
125 				"\001SIMPLEX"				\
126 				"\002AUTOVCHAN"				\
127 				"\003SOFTPCMVOL"			\
128 				"\004BUSY"				\
129 				"\005MPSAFE"				\
130 				"\006REGISTERED"			\
131 				"\007BITPERFECT"			\
132 				"\010VPC"				\
133 				"\011EQ"				\
134 				"\012EQ_ENABLED"			\
135 				"\013EQ_BYPASSED"			\
136 				"\014EQ_PC"				\
137 				"\035PRIO_RD"				\
138 				"\036PRIO_WR"
139 
140 #define PCM_ALIVE(x)		((x) != NULL && (x)->lock != NULL)
141 #define PCM_REGISTERED(x)	(PCM_ALIVE(x) && ((x)->flags & SD_F_REGISTERED))
142 
143 #define	PCM_CHANCOUNT(d)	\
144 	(d->playcount + d->pvchancount + d->reccount + d->rvchancount)
145 
146 /* many variables should be reduced to a range. Here define a macro */
147 #define RANGE(var, low, high) (var) = \
148 	(((var)<(low))? (low) : ((var)>(high))? (high) : (var))
149 
150 /* make figuring out what a format is easier. got AFMT_STEREO already */
151 #define AFMT_32BIT (AFMT_S32_LE | AFMT_S32_BE | AFMT_U32_LE | AFMT_U32_BE)
152 #define AFMT_24BIT (AFMT_S24_LE | AFMT_S24_BE | AFMT_U24_LE | AFMT_U24_BE)
153 #define AFMT_16BIT (AFMT_S16_LE | AFMT_S16_BE | AFMT_U16_LE | AFMT_U16_BE)
154 #define AFMT_G711  (AFMT_MU_LAW | AFMT_A_LAW)
155 #define AFMT_8BIT (AFMT_G711 | AFMT_U8 | AFMT_S8)
156 #define AFMT_SIGNED (AFMT_S32_LE | AFMT_S32_BE | AFMT_S24_LE | AFMT_S24_BE | \
157 			AFMT_S16_LE | AFMT_S16_BE | AFMT_S8)
158 #define AFMT_BIGENDIAN (AFMT_S32_BE | AFMT_U32_BE | AFMT_S24_BE | AFMT_U24_BE | \
159 			AFMT_S16_BE | AFMT_U16_BE)
160 
161 #define AFMT_CONVERTIBLE	(AFMT_8BIT | AFMT_16BIT | AFMT_24BIT |	\
162 				 AFMT_32BIT)
163 
164 /* Supported vchan mixing formats */
165 #define AFMT_VCHAN		(AFMT_CONVERTIBLE & ~AFMT_G711)
166 
167 #define AFMT_PASSTHROUGH		AFMT_AC3
168 #define AFMT_PASSTHROUGH_RATE		48000
169 #define AFMT_PASSTHROUGH_CHANNEL	2
170 #define AFMT_PASSTHROUGH_EXTCHANNEL	0
171 
172 /*
173  * We're simply using unused, contiguous bits from various AFMT_ definitions.
174  * ~(0xb00ff7ff)
175  */
176 #define AFMT_ENCODING_MASK	0xf00fffff
177 #define AFMT_CHANNEL_MASK	0x07f00000
178 #define AFMT_CHANNEL_SHIFT	20
179 #define AFMT_CHANNEL_MAX	0x7f
180 #define AFMT_EXTCHANNEL_MASK	0x08000000
181 #define AFMT_EXTCHANNEL_SHIFT	27
182 #define AFMT_EXTCHANNEL_MAX	1
183 
184 #define AFMT_ENCODING(v)	((v) & AFMT_ENCODING_MASK)
185 
186 #define AFMT_EXTCHANNEL(v)	(((v) & AFMT_EXTCHANNEL_MASK) >>	\
187 				AFMT_EXTCHANNEL_SHIFT)
188 
189 #define AFMT_CHANNEL(v)		(((v) & AFMT_CHANNEL_MASK) >>		\
190 				AFMT_CHANNEL_SHIFT)
191 
192 #define AFMT_BIT(v)		(((v) & AFMT_32BIT) ? 32 :		\
193 				(((v) & AFMT_24BIT) ? 24 :		\
194 				((((v) & AFMT_16BIT) ||			\
195 				((v) & AFMT_PASSTHROUGH)) ? 16 : 8)))
196 
197 #define AFMT_BPS(v)		(AFMT_BIT(v) >> 3)
198 #define AFMT_ALIGN(v)		(AFMT_BPS(v) * AFMT_CHANNEL(v))
199 
200 #define SND_FORMAT(f, c, e)	(AFMT_ENCODING(f) |		\
201 				(((c) << AFMT_CHANNEL_SHIFT) &		\
202 				AFMT_CHANNEL_MASK) |			\
203 				(((e) << AFMT_EXTCHANNEL_SHIFT) &	\
204 				AFMT_EXTCHANNEL_MASK))
205 
206 #define AFMT_U8_NE	AFMT_U8
207 #define AFMT_S8_NE	AFMT_S8
208 
209 #define AFMT_SIGNED_NE	(AFMT_S8_NE | AFMT_S16_NE | AFMT_S24_NE | AFMT_S32_NE)
210 
211 #define AFMT_NE		(AFMT_SIGNED_NE | AFMT_U8_NE | AFMT_U16_NE |	\
212 			 AFMT_U24_NE | AFMT_U32_NE)
213 
214 enum {
215 	SND_DEV_CTL = 0,	/* Control port /dev/mixer */
216 	SND_DEV_SEQ,		/* Sequencer /dev/sequencer */
217 	SND_DEV_MIDIN,		/* Raw midi access */
218 	SND_DEV_DSP,		/* Digitized voice /dev/dsp */
219 	SND_DEV_STATUS,		/* /dev/sndstat */
220 };
221 
222 #define DSP_DEFAULT_SPEED	8000
223 
224 extern int snd_unit;
225 extern int snd_verbose;
226 extern devclass_t pcm_devclass;
227 extern struct unrhdr *pcmsg_unrhdr;
228 
229 #ifndef DEB
230 #define DEB(x)
231 #endif
232 
233 SYSCTL_DECL(_hw_snd);
234 
235 int pcm_chnalloc(struct snddev_info *d, struct pcm_channel **ch, int direction,
236     pid_t pid, char *comm);
237 
238 int pcm_addchan(device_t dev, int dir, kobj_class_t cls, void *devinfo);
239 unsigned int pcm_getbuffersize(device_t dev, unsigned int minbufsz, unsigned int deflt, unsigned int maxbufsz);
240 void pcm_init(device_t dev, void *devinfo);
241 int pcm_register(device_t dev, char *str);
242 int pcm_unregister(device_t dev);
243 u_int32_t pcm_getflags(device_t dev);
244 void pcm_setflags(device_t dev, u_int32_t val);
245 void *pcm_getdevinfo(device_t dev);
246 
247 int snd_setup_intr(device_t dev, struct resource *res, int flags,
248 		   driver_intr_t hand, void *param, void **cookiep);
249 
250 void *snd_mtxcreate(const char *desc, const char *type);
251 void snd_mtxfree(void *m);
252 void snd_mtxassert(void *m);
253 #define	snd_mtxlock(m) mtx_lock(m)
254 #define	snd_mtxunlock(m) mtx_unlock(m)
255 
256 int sndstat_register(device_t dev, char *str);
257 int sndstat_unregister(device_t dev);
258 
259 /* These are the function codes assigned to the children of sound cards. */
260 enum {
261 	SCF_PCM,
262 	SCF_MIDI,
263 	SCF_SYNTH,
264 };
265 
266 /*
267  * This is the device information struct, used by a bridge device to pass the
268  * device function code to the children.
269  */
270 struct sndcard_func {
271 	int func;	/* The function code. */
272 	void *varinfo;	/* Bridge-specific information. */
273 };
274 
275 /*
276  * this is rather kludgey- we need to duplicate these struct def'ns from sound.c
277  * so that the macro versions of pcm_{,un}lock can dereference them.
278  * we also have to do this now makedev() has gone away.
279  */
280 
281 struct snddev_info {
282 	struct {
283 		struct {
284 			SLIST_HEAD(, pcm_channel) head;
285 			struct {
286 				SLIST_HEAD(, pcm_channel) head;
287 			} busy;
288 			struct {
289 				SLIST_HEAD(, pcm_channel) head;
290 			} opened;
291 		} pcm;
292 	} channels;
293 	unsigned playcount, reccount, pvchancount, rvchancount;
294 	unsigned flags;
295 	unsigned int bufsz;
296 	void *devinfo;
297 	device_t dev;
298 	char status[SND_STATUSLEN];
299 	struct mtx *lock;
300 	struct cdev *mixer_dev;
301 	struct cdev *dsp_dev;
302 	uint32_t pvchanrate, pvchanformat;
303 	uint32_t rvchanrate, rvchanformat;
304 	int32_t eqpreamp;
305 	struct sysctl_ctx_list play_sysctl_ctx, rec_sysctl_ctx;
306 	struct sysctl_oid *play_sysctl_tree, *rec_sysctl_tree;
307 	struct cv cv;
308 	struct unrhdr *p_unr;
309 	struct unrhdr *vp_unr;
310 	struct unrhdr *r_unr;
311 	struct unrhdr *vr_unr;
312 };
313 
314 void	sound_oss_sysinfo(oss_sysinfo *);
315 int	sound_oss_card_info(oss_card_info *);
316 
317 #define	PCM_MODE_MIXER		0x01
318 #define	PCM_MODE_PLAY		0x02
319 #define	PCM_MODE_REC		0x04
320 
321 #define PCM_LOCKOWNED(d)	mtx_owned((d)->lock)
322 #define	PCM_LOCK(d)		mtx_lock((d)->lock)
323 #define	PCM_UNLOCK(d)		mtx_unlock((d)->lock)
324 #define PCM_TRYLOCK(d)		mtx_trylock((d)->lock)
325 #define PCM_LOCKASSERT(d)	mtx_assert((d)->lock, MA_OWNED)
326 #define PCM_UNLOCKASSERT(d)	mtx_assert((d)->lock, MA_NOTOWNED)
327 
328 /*
329  * For PCM_[WAIT | ACQUIRE | RELEASE], be sure to surround these
330  * with PCM_LOCK/UNLOCK() sequence, or I'll come to gnaw upon you!
331  */
332 #ifdef SND_DIAGNOSTIC
333 #define PCM_WAIT(x)		do {					\
334 	if (!PCM_LOCKOWNED(x))						\
335 		panic("%s(%d): [PCM WAIT] Mutex not owned!",		\
336 		    __func__, __LINE__);				\
337 	while ((x)->flags & SD_F_BUSY) {				\
338 		if (snd_verbose > 3)					\
339 			device_printf((x)->dev,				\
340 			    "%s(%d): [PCM WAIT] calling cv_wait().\n",	\
341 			    __func__, __LINE__);			\
342 		cv_wait(&(x)->cv, (x)->lock);				\
343 	}								\
344 } while (0)
345 
346 #define PCM_ACQUIRE(x)		do {					\
347 	if (!PCM_LOCKOWNED(x))						\
348 		panic("%s(%d): [PCM ACQUIRE] Mutex not owned!",		\
349 		    __func__, __LINE__);				\
350 	if ((x)->flags & SD_F_BUSY)					\
351 		panic("%s(%d): [PCM ACQUIRE] "				\
352 		    "Trying to acquire BUSY cv!", __func__, __LINE__);	\
353 	(x)->flags |= SD_F_BUSY;					\
354 } while (0)
355 
356 #define PCM_RELEASE(x)		do {					\
357 	if (!PCM_LOCKOWNED(x))						\
358 		panic("%s(%d): [PCM RELEASE] Mutex not owned!",		\
359 		    __func__, __LINE__);				\
360 	if ((x)->flags & SD_F_BUSY) {					\
361 		(x)->flags &= ~SD_F_BUSY;				\
362 		if ((x)->cv.cv_waiters != 0) {				\
363 			if ((x)->cv.cv_waiters > 1 && snd_verbose > 3)	\
364 				device_printf((x)->dev,			\
365 				    "%s(%d): [PCM RELEASE] "		\
366 				    "cv_waiters=%d > 1!\n",		\
367 				    __func__, __LINE__,			\
368 				    (x)->cv.cv_waiters);		\
369 			cv_broadcast(&(x)->cv);				\
370 		}							\
371 	} else								\
372 		panic("%s(%d): [PCM RELEASE] Releasing non-BUSY cv!",	\
373 		    __func__, __LINE__);				\
374 } while (0)
375 
376 /* Quick version, for shorter path. */
377 #define PCM_ACQUIRE_QUICK(x)	do {					\
378 	if (PCM_LOCKOWNED(x))						\
379 		panic("%s(%d): [PCM ACQUIRE QUICK] Mutex owned!",	\
380 		    __func__, __LINE__);				\
381 	PCM_LOCK(x);							\
382 	PCM_WAIT(x);							\
383 	PCM_ACQUIRE(x);							\
384 	PCM_UNLOCK(x);							\
385 } while (0)
386 
387 #define PCM_RELEASE_QUICK(x)	do {					\
388 	if (PCM_LOCKOWNED(x))						\
389 		panic("%s(%d): [PCM RELEASE QUICK] Mutex owned!",	\
390 		    __func__, __LINE__);				\
391 	PCM_LOCK(x);							\
392 	PCM_RELEASE(x);							\
393 	PCM_UNLOCK(x);							\
394 } while (0)
395 
396 #define PCM_BUSYASSERT(x)	do {					\
397 	if (!((x) != NULL && ((x)->flags & SD_F_BUSY)))			\
398 		panic("%s(%d): [PCM BUSYASSERT] "			\
399 		    "Failed, snddev_info=%p", __func__, __LINE__, x);	\
400 } while (0)
401 
402 #define PCM_GIANT_ENTER(x)	do {					\
403 	int _pcm_giant = 0;						\
404 	if (PCM_LOCKOWNED(x))						\
405 		panic("%s(%d): [GIANT ENTER] PCM lock owned!",		\
406 		    __func__, __LINE__);				\
407 	if (mtx_owned(&Giant) != 0 && snd_verbose > 3)			\
408 		device_printf((x)->dev,					\
409 		    "%s(%d): [GIANT ENTER] Giant owned!\n",		\
410 		    __func__, __LINE__);				\
411 	if (!((x)->flags & SD_F_MPSAFE) && mtx_owned(&Giant) == 0)	\
412 		do {							\
413 			mtx_lock(&Giant);				\
414 			_pcm_giant = 1;					\
415 		} while (0)
416 
417 #define PCM_GIANT_EXIT(x)	do {					\
418 	if (PCM_LOCKOWNED(x))						\
419 		panic("%s(%d): [GIANT EXIT] PCM lock owned!",		\
420 		    __func__, __LINE__);				\
421 	if (!(_pcm_giant == 0 || _pcm_giant == 1))			\
422 		panic("%s(%d): [GIANT EXIT] _pcm_giant screwed!",	\
423 		    __func__, __LINE__);				\
424 	if ((x)->flags & SD_F_MPSAFE) {					\
425 		if (_pcm_giant == 1)					\
426 			panic("%s(%d): [GIANT EXIT] MPSAFE Giant?",	\
427 			    __func__, __LINE__);			\
428 		if (mtx_owned(&Giant) != 0 && snd_verbose > 3)		\
429 			device_printf((x)->dev,				\
430 			    "%s(%d): [GIANT EXIT] Giant owned!\n",	\
431 			    __func__, __LINE__);			\
432 	}								\
433 	if (_pcm_giant != 0) {						\
434 		if (mtx_owned(&Giant) == 0)				\
435 			panic("%s(%d): [GIANT EXIT] Giant not owned!",	\
436 			    __func__, __LINE__);			\
437 		_pcm_giant = 0;						\
438 		mtx_unlock(&Giant);					\
439 	}								\
440 } while (0)
441 #else /* !SND_DIAGNOSTIC */
442 #define PCM_WAIT(x)		do {					\
443 	PCM_LOCKASSERT(x);						\
444 	while ((x)->flags & SD_F_BUSY)					\
445 		cv_wait(&(x)->cv, (x)->lock);				\
446 } while (0)
447 
448 #define PCM_ACQUIRE(x)		do {					\
449 	PCM_LOCKASSERT(x);						\
450 	KASSERT(!((x)->flags & SD_F_BUSY),				\
451 	    ("%s(%d): [PCM ACQUIRE] Trying to acquire BUSY cv!",	\
452 	    __func__, __LINE__));					\
453 	(x)->flags |= SD_F_BUSY;					\
454 } while (0)
455 
456 #define PCM_RELEASE(x)		do {					\
457 	PCM_LOCKASSERT(x);						\
458 	KASSERT((x)->flags & SD_F_BUSY,					\
459 	    ("%s(%d): [PCM RELEASE] Releasing non-BUSY cv!",		\
460 	    __func__, __LINE__));					\
461 	(x)->flags &= ~SD_F_BUSY;					\
462 	if ((x)->cv.cv_waiters != 0)					\
463 		cv_broadcast(&(x)->cv);					\
464 } while (0)
465 
466 /* Quick version, for shorter path. */
467 #define PCM_ACQUIRE_QUICK(x)	do {					\
468 	PCM_UNLOCKASSERT(x);						\
469 	PCM_LOCK(x);							\
470 	PCM_WAIT(x);							\
471 	PCM_ACQUIRE(x);							\
472 	PCM_UNLOCK(x);							\
473 } while (0)
474 
475 #define PCM_RELEASE_QUICK(x)	do {					\
476 	PCM_UNLOCKASSERT(x);						\
477 	PCM_LOCK(x);							\
478 	PCM_RELEASE(x);							\
479 	PCM_UNLOCK(x);							\
480 } while (0)
481 
482 #define PCM_BUSYASSERT(x)	KASSERT(x != NULL &&			\
483 				    ((x)->flags & SD_F_BUSY),		\
484 				    ("%s(%d): [PCM BUSYASSERT] "	\
485 				    "Failed, snddev_info=%p",		\
486 				    __func__, __LINE__, x))
487 
488 #define PCM_GIANT_ENTER(x)	do {					\
489 	int _pcm_giant = 0;						\
490 	PCM_UNLOCKASSERT(x);						\
491 	if (!((x)->flags & SD_F_MPSAFE) && mtx_owned(&Giant) == 0)	\
492 		do {							\
493 			mtx_lock(&Giant);				\
494 			_pcm_giant = 1;					\
495 		} while (0)
496 
497 #define PCM_GIANT_EXIT(x)	do {					\
498 	PCM_UNLOCKASSERT(x);						\
499 	KASSERT(_pcm_giant == 0 || _pcm_giant == 1,			\
500 	    ("%s(%d): [GIANT EXIT] _pcm_giant screwed!",		\
501 	    __func__, __LINE__));					\
502 	KASSERT(!((x)->flags & SD_F_MPSAFE) ||				\
503 	    (((x)->flags & SD_F_MPSAFE) && _pcm_giant == 0),		\
504 	    ("%s(%d): [GIANT EXIT] MPSAFE Giant?",			\
505 	    __func__, __LINE__));					\
506 	if (_pcm_giant != 0) {						\
507 		mtx_assert(&Giant, MA_OWNED);				\
508 		_pcm_giant = 0;						\
509 		mtx_unlock(&Giant);					\
510 	}								\
511 } while (0)
512 #endif /* SND_DIAGNOSTIC */
513 
514 #define PCM_GIANT_LEAVE(x)						\
515 	PCM_GIANT_EXIT(x);						\
516 } while (0)
517 
518 #endif /* _KERNEL */
519 
520 #endif	/* _OS_H_ */
521