xref: /freebsd/sys/dev/sound/pcm/feeder_mixer.c (revision 5aacf339)
190da2b28SAriff Abdullah /*-
24d846d26SWarner Losh  * SPDX-License-Identifier: BSD-2-Clause
3718cf2ccSPedro F. Giffuni  *
490da2b28SAriff Abdullah  * Copyright (c) 2008-2009 Ariff Abdullah <ariff@FreeBSD.org>
590da2b28SAriff Abdullah  * All rights reserved.
690da2b28SAriff Abdullah  *
790da2b28SAriff Abdullah  * Redistribution and use in source and binary forms, with or without
890da2b28SAriff Abdullah  * modification, are permitted provided that the following conditions
990da2b28SAriff Abdullah  * are met:
1090da2b28SAriff Abdullah  * 1. Redistributions of source code must retain the above copyright
1190da2b28SAriff Abdullah  *    notice, this list of conditions and the following disclaimer.
1290da2b28SAriff Abdullah  * 2. Redistributions in binary form must reproduce the above copyright
1390da2b28SAriff Abdullah  *    notice, this list of conditions and the following disclaimer in the
1490da2b28SAriff Abdullah  *    documentation and/or other materials provided with the distribution.
1590da2b28SAriff Abdullah  *
1690da2b28SAriff Abdullah  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
1790da2b28SAriff Abdullah  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1890da2b28SAriff Abdullah  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
1990da2b28SAriff Abdullah  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
2090da2b28SAriff Abdullah  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
2190da2b28SAriff Abdullah  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2290da2b28SAriff Abdullah  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
2390da2b28SAriff Abdullah  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
2490da2b28SAriff Abdullah  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
2590da2b28SAriff Abdullah  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
2690da2b28SAriff Abdullah  * SUCH DAMAGE.
2790da2b28SAriff Abdullah  */
2890da2b28SAriff Abdullah 
2990da2b28SAriff Abdullah #ifdef _KERNEL
3090da2b28SAriff Abdullah #ifdef HAVE_KERNEL_OPTION_HEADERS
3190da2b28SAriff Abdullah #include "opt_snd.h"
3290da2b28SAriff Abdullah #endif
3390da2b28SAriff Abdullah #include <dev/sound/pcm/sound.h>
3490da2b28SAriff Abdullah #include <dev/sound/pcm/pcm.h>
3590da2b28SAriff Abdullah #include <dev/sound/pcm/vchan.h>
3690da2b28SAriff Abdullah #include "feeder_if.h"
3790da2b28SAriff Abdullah 
3890da2b28SAriff Abdullah #define SND_USE_FXDIV
3990da2b28SAriff Abdullah #include "snd_fxdiv_gen.h"
4090da2b28SAriff Abdullah #endif
4190da2b28SAriff Abdullah 
4290da2b28SAriff Abdullah #undef SND_FEEDER_MULTIFORMAT
4390da2b28SAriff Abdullah #define SND_FEEDER_MULTIFORMAT	1
4490da2b28SAriff Abdullah 
4590da2b28SAriff Abdullah typedef void (*feed_mixer_t)(uint8_t *, uint8_t *, uint32_t);
4690da2b28SAriff Abdullah 
4790da2b28SAriff Abdullah #define FEEDMIXER_DECLARE(SIGN, BIT, ENDIAN)				\
4890da2b28SAriff Abdullah static void								\
4990da2b28SAriff Abdullah feed_mixer_##SIGN##BIT##ENDIAN(uint8_t *src, uint8_t *dst,		\
5090da2b28SAriff Abdullah     uint32_t count)							\
5190da2b28SAriff Abdullah {									\
5290da2b28SAriff Abdullah 	intpcm##BIT##_t z;						\
5390da2b28SAriff Abdullah 	intpcm_t x, y;							\
5490da2b28SAriff Abdullah 									\
5590da2b28SAriff Abdullah 	src += count;							\
5690da2b28SAriff Abdullah 	dst += count;							\
5790da2b28SAriff Abdullah 									\
5890da2b28SAriff Abdullah 	do {								\
5990da2b28SAriff Abdullah 		src -= PCM_##BIT##_BPS;					\
6090da2b28SAriff Abdullah 		dst -= PCM_##BIT##_BPS;					\
6190da2b28SAriff Abdullah 		count -= PCM_##BIT##_BPS;				\
6290da2b28SAriff Abdullah 		x = PCM_READ_##SIGN##BIT##_##ENDIAN(src);		\
6390da2b28SAriff Abdullah 		y = PCM_READ_##SIGN##BIT##_##ENDIAN(dst);		\
6490da2b28SAriff Abdullah 		z = INTPCM##BIT##_T(x) + y;				\
6590da2b28SAriff Abdullah 		x = PCM_CLAMP_##SIGN##BIT(z);				\
6690da2b28SAriff Abdullah 		_PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst, x);		\
6790da2b28SAriff Abdullah 	} while (count != 0);						\
6890da2b28SAriff Abdullah }
6990da2b28SAriff Abdullah 
7090da2b28SAriff Abdullah #if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
7190da2b28SAriff Abdullah FEEDMIXER_DECLARE(S, 16, LE)
7290da2b28SAriff Abdullah FEEDMIXER_DECLARE(S, 32, LE)
7390da2b28SAriff Abdullah #endif
7490da2b28SAriff Abdullah #if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
7590da2b28SAriff Abdullah FEEDMIXER_DECLARE(S, 16, BE)
7690da2b28SAriff Abdullah FEEDMIXER_DECLARE(S, 32, BE)
7790da2b28SAriff Abdullah #endif
7890da2b28SAriff Abdullah #ifdef SND_FEEDER_MULTIFORMAT
7990da2b28SAriff Abdullah FEEDMIXER_DECLARE(S,  8, NE)
8090da2b28SAriff Abdullah FEEDMIXER_DECLARE(S, 24, LE)
8190da2b28SAriff Abdullah FEEDMIXER_DECLARE(S, 24, BE)
8290da2b28SAriff Abdullah FEEDMIXER_DECLARE(U,  8, NE)
8390da2b28SAriff Abdullah FEEDMIXER_DECLARE(U, 16, LE)
8490da2b28SAriff Abdullah FEEDMIXER_DECLARE(U, 24, LE)
8590da2b28SAriff Abdullah FEEDMIXER_DECLARE(U, 32, LE)
8690da2b28SAriff Abdullah FEEDMIXER_DECLARE(U, 16, BE)
8790da2b28SAriff Abdullah FEEDMIXER_DECLARE(U, 24, BE)
8890da2b28SAriff Abdullah FEEDMIXER_DECLARE(U, 32, BE)
8990da2b28SAriff Abdullah #endif
9090da2b28SAriff Abdullah 
9190da2b28SAriff Abdullah struct feed_mixer_info {
9290da2b28SAriff Abdullah 	uint32_t format;
9390da2b28SAriff Abdullah 	int bps;
9490da2b28SAriff Abdullah 	feed_mixer_t mix;
9590da2b28SAriff Abdullah };
9690da2b28SAriff Abdullah 
9790da2b28SAriff Abdullah #define FEEDMIXER_ENTRY(SIGN, BIT, ENDIAN)				\
9890da2b28SAriff Abdullah 	{								\
9990da2b28SAriff Abdullah 		AFMT_##SIGN##BIT##_##ENDIAN, PCM_##BIT##_BPS,		\
10090da2b28SAriff Abdullah 		feed_mixer_##SIGN##BIT##ENDIAN				\
10190da2b28SAriff Abdullah 	}
10290da2b28SAriff Abdullah 
10390da2b28SAriff Abdullah static struct feed_mixer_info feed_mixer_info_tab[] = {
10490da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(S,  8, NE),
10590da2b28SAriff Abdullah #if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
10690da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(S, 16, LE),
10790da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(S, 32, LE),
10890da2b28SAriff Abdullah #endif
10990da2b28SAriff Abdullah #if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
11090da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(S, 16, BE),
11190da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(S, 32, BE),
11290da2b28SAriff Abdullah #endif
11390da2b28SAriff Abdullah #ifdef SND_FEEDER_MULTIFORMAT
11490da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(S, 24, LE),
11590da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(S, 24, BE),
11690da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(U,  8, NE),
11790da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(U, 16, LE),
11890da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(U, 24, LE),
11990da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(U, 32, LE),
12090da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(U, 16, BE),
12190da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(U, 24, BE),
12290da2b28SAriff Abdullah 	FEEDMIXER_ENTRY(U, 32, BE),
12390da2b28SAriff Abdullah #endif
12490da2b28SAriff Abdullah 	{    AFMT_AC3, PCM_16_BPS, NULL },
12590da2b28SAriff Abdullah 	{ AFMT_MU_LAW,  PCM_8_BPS, feed_mixer_U8NE },	/* dummy */
12690da2b28SAriff Abdullah 	{  AFMT_A_LAW,  PCM_8_BPS, feed_mixer_U8NE }	/* dummy */
12790da2b28SAriff Abdullah };
12890da2b28SAriff Abdullah 
12990da2b28SAriff Abdullah #define FEEDMIXER_TAB_SIZE	((int32_t)				\
13090da2b28SAriff Abdullah 				 (sizeof(feed_mixer_info_tab) /		\
13190da2b28SAriff Abdullah 				  sizeof(feed_mixer_info_tab[0])))
13290da2b28SAriff Abdullah 
13390da2b28SAriff Abdullah #define FEEDMIXER_DATA(i, c)	((void *)				\
1340f86d40bSHans Petter Selasky 				 ((uintptr_t)((((i) & 0x1f) << 7) |	\
1350f86d40bSHans Petter Selasky 				 ((c) & 0x7f))))
1360f86d40bSHans Petter Selasky #define FEEDMIXER_INFOIDX(d)	((uint32_t)((uintptr_t)(d) >> 7) & 0x1f)
1370f86d40bSHans Petter Selasky #define FEEDMIXER_CHANNELS(d)	((uint32_t)((uintptr_t)(d)) & 0x7f)
13890da2b28SAriff Abdullah 
13990da2b28SAriff Abdullah static int
feed_mixer_init(struct pcm_feeder * f)14090da2b28SAriff Abdullah feed_mixer_init(struct pcm_feeder *f)
14190da2b28SAriff Abdullah {
14290da2b28SAriff Abdullah 	int i;
14390da2b28SAriff Abdullah 
14490da2b28SAriff Abdullah 	if (f->desc->in != f->desc->out)
14590da2b28SAriff Abdullah 		return (EINVAL);
14690da2b28SAriff Abdullah 
14790da2b28SAriff Abdullah 	for (i = 0; i < FEEDMIXER_TAB_SIZE; i++) {
14890da2b28SAriff Abdullah 		if (AFMT_ENCODING(f->desc->in) ==
14990da2b28SAriff Abdullah 		    feed_mixer_info_tab[i].format) {
15090da2b28SAriff Abdullah 		    	f->data =
15190da2b28SAriff Abdullah 			    FEEDMIXER_DATA(i, AFMT_CHANNEL(f->desc->in));
15290da2b28SAriff Abdullah 			return (0);
15390da2b28SAriff Abdullah 		}
15490da2b28SAriff Abdullah 	}
15590da2b28SAriff Abdullah 
15690da2b28SAriff Abdullah 	return (EINVAL);
15790da2b28SAriff Abdullah }
15890da2b28SAriff Abdullah 
15990da2b28SAriff Abdullah static int
feed_mixer_set(struct pcm_feeder * f,int what,int value)16090da2b28SAriff Abdullah feed_mixer_set(struct pcm_feeder *f, int what, int value)
16190da2b28SAriff Abdullah {
16290da2b28SAriff Abdullah 
16390da2b28SAriff Abdullah 	switch (what) {
16490da2b28SAriff Abdullah 	case FEEDMIXER_CHANNELS:
16590da2b28SAriff Abdullah 		if (value < SND_CHN_MIN || value > SND_CHN_MAX)
16690da2b28SAriff Abdullah 			return (EINVAL);
16790da2b28SAriff Abdullah 		f->data = FEEDMIXER_DATA(FEEDMIXER_INFOIDX(f->data), value);
16890da2b28SAriff Abdullah 		break;
16990da2b28SAriff Abdullah 	default:
17090da2b28SAriff Abdullah 		return (EINVAL);
17190da2b28SAriff Abdullah 		break;
17290da2b28SAriff Abdullah 	}
17390da2b28SAriff Abdullah 
17490da2b28SAriff Abdullah 	return (0);
17590da2b28SAriff Abdullah }
17690da2b28SAriff Abdullah 
17790da2b28SAriff Abdullah static __inline int
feed_mixer_rec(struct pcm_channel * c)17890da2b28SAriff Abdullah feed_mixer_rec(struct pcm_channel *c)
17990da2b28SAriff Abdullah {
18090da2b28SAriff Abdullah 	struct pcm_channel *ch;
18190da2b28SAriff Abdullah 	struct snd_dbuf *b, *bs;
18290da2b28SAriff Abdullah 	uint32_t cnt, maxfeed;
18390da2b28SAriff Abdullah 	int rdy;
18490da2b28SAriff Abdullah 
18590da2b28SAriff Abdullah 	/*
18690da2b28SAriff Abdullah 	 * Reset ready and moving pointer. We're not using bufsoft
18790da2b28SAriff Abdullah 	 * anywhere since its sole purpose is to become the primary
18890da2b28SAriff Abdullah 	 * distributor for the recorded buffer and also as an interrupt
18990da2b28SAriff Abdullah 	 * threshold progress indicator.
19090da2b28SAriff Abdullah 	 */
19190da2b28SAriff Abdullah 	b = c->bufsoft;
19290da2b28SAriff Abdullah 	b->rp = 0;
19390da2b28SAriff Abdullah 	b->rl = 0;
19490da2b28SAriff Abdullah 	cnt = sndbuf_getsize(b);
19590da2b28SAriff Abdullah 	maxfeed = SND_FXROUND(SND_FXDIV_MAX, sndbuf_getalign(b));
19690da2b28SAriff Abdullah 
19790da2b28SAriff Abdullah 	do {
19890da2b28SAriff Abdullah 		cnt = FEEDER_FEED(c->feeder->source, c, b->tmpbuf,
19990da2b28SAriff Abdullah 		    min(cnt, maxfeed), c->bufhard);
20090da2b28SAriff Abdullah 		if (cnt != 0) {
20190da2b28SAriff Abdullah 			sndbuf_acquire(b, b->tmpbuf, cnt);
20290da2b28SAriff Abdullah 			cnt = sndbuf_getfree(b);
20390da2b28SAriff Abdullah 		}
20490da2b28SAriff Abdullah 	} while (cnt != 0);
20590da2b28SAriff Abdullah 
20690da2b28SAriff Abdullah 	/* Not enough data */
20790da2b28SAriff Abdullah 	if (b->rl < sndbuf_getalign(b)) {
20890da2b28SAriff Abdullah 		b->rl = 0;
20990da2b28SAriff Abdullah 		return (0);
21090da2b28SAriff Abdullah 	}
21190da2b28SAriff Abdullah 
21290da2b28SAriff Abdullah 	/*
21390da2b28SAriff Abdullah 	 * Keep track of ready and moving pointer since we will use
21490da2b28SAriff Abdullah 	 * bufsoft over and over again, pretending nothing has happened.
21590da2b28SAriff Abdullah 	 */
21690da2b28SAriff Abdullah 	rdy = b->rl;
21790da2b28SAriff Abdullah 
21890da2b28SAriff Abdullah 	CHN_FOREACH(ch, c, children.busy) {
21990da2b28SAriff Abdullah 		CHN_LOCK(ch);
22090da2b28SAriff Abdullah 		if (CHN_STOPPED(ch) || (ch->flags & CHN_F_DIRTY)) {
22190da2b28SAriff Abdullah 			CHN_UNLOCK(ch);
22290da2b28SAriff Abdullah 			continue;
22390da2b28SAriff Abdullah 		}
22490da2b28SAriff Abdullah #ifdef SND_DEBUG
22590da2b28SAriff Abdullah 		if ((c->flags & CHN_F_DIRTY) && VCHAN_SYNC_REQUIRED(ch)) {
22690da2b28SAriff Abdullah 			if (vchan_sync(ch) != 0) {
22790da2b28SAriff Abdullah 				CHN_UNLOCK(ch);
22890da2b28SAriff Abdullah 				continue;
22990da2b28SAriff Abdullah 			}
23090da2b28SAriff Abdullah 		}
23190da2b28SAriff Abdullah #endif
23290da2b28SAriff Abdullah 		bs = ch->bufsoft;
23390da2b28SAriff Abdullah 		if (ch->flags & CHN_F_MMAP)
23490da2b28SAriff Abdullah 			sndbuf_dispose(bs, NULL, sndbuf_getready(bs));
23590da2b28SAriff Abdullah 		cnt = sndbuf_getfree(bs);
23690da2b28SAriff Abdullah 		if (cnt < sndbuf_getalign(bs)) {
23790da2b28SAriff Abdullah 			CHN_UNLOCK(ch);
23890da2b28SAriff Abdullah 			continue;
23990da2b28SAriff Abdullah 		}
24090da2b28SAriff Abdullah 		maxfeed = SND_FXROUND(SND_FXDIV_MAX, sndbuf_getalign(bs));
24190da2b28SAriff Abdullah 		do {
24290da2b28SAriff Abdullah 			cnt = FEEDER_FEED(ch->feeder, ch, bs->tmpbuf,
24390da2b28SAriff Abdullah 			    min(cnt, maxfeed), b);
24490da2b28SAriff Abdullah 			if (cnt != 0) {
24590da2b28SAriff Abdullah 				sndbuf_acquire(bs, bs->tmpbuf, cnt);
24690da2b28SAriff Abdullah 				cnt = sndbuf_getfree(bs);
24790da2b28SAriff Abdullah 			}
24890da2b28SAriff Abdullah 		} while (cnt != 0);
24990da2b28SAriff Abdullah 		/*
25090da2b28SAriff Abdullah 		 * Not entirely flushed out...
25190da2b28SAriff Abdullah 		 */
25290da2b28SAriff Abdullah 		if (b->rl != 0)
25390da2b28SAriff Abdullah 			ch->xruns++;
25490da2b28SAriff Abdullah 		CHN_UNLOCK(ch);
25590da2b28SAriff Abdullah 		/*
25690da2b28SAriff Abdullah 		 * Rewind buffer position for next virtual channel.
25790da2b28SAriff Abdullah 		 */
25890da2b28SAriff Abdullah 		b->rp = 0;
25990da2b28SAriff Abdullah 		b->rl = rdy;
26090da2b28SAriff Abdullah 	}
26190da2b28SAriff Abdullah 
26290da2b28SAriff Abdullah 	/*
26390da2b28SAriff Abdullah 	 * Set ready pointer to indicate that our children are ready
26490da2b28SAriff Abdullah 	 * to be woken up, also as an interrupt threshold progress
26590da2b28SAriff Abdullah 	 * indicator.
26690da2b28SAriff Abdullah 	 */
26790da2b28SAriff Abdullah 	b->rl = 1;
26890da2b28SAriff Abdullah 
26990da2b28SAriff Abdullah 	c->flags &= ~CHN_F_DIRTY;
27090da2b28SAriff Abdullah 
27190da2b28SAriff Abdullah 	/*
27290da2b28SAriff Abdullah 	 * Return 0 to bail out early from sndbuf_feed() loop.
27390da2b28SAriff Abdullah 	 * No need to increase feedcount counter since part of this
27490da2b28SAriff Abdullah 	 * feeder chains already include feed_root().
27590da2b28SAriff Abdullah 	 */
27690da2b28SAriff Abdullah 	return (0);
27790da2b28SAriff Abdullah }
27890da2b28SAriff Abdullah 
27990da2b28SAriff Abdullah static int
feed_mixer_feed(struct pcm_feeder * f,struct pcm_channel * c,uint8_t * b,uint32_t count,void * source)28090da2b28SAriff Abdullah feed_mixer_feed(struct pcm_feeder *f, struct pcm_channel *c, uint8_t *b,
28190da2b28SAriff Abdullah     uint32_t count, void *source)
28290da2b28SAriff Abdullah {
28390da2b28SAriff Abdullah 	struct feed_mixer_info *info;
28490da2b28SAriff Abdullah 	struct snd_dbuf *src = source;
28590da2b28SAriff Abdullah 	struct pcm_channel *ch;
28690da2b28SAriff Abdullah 	uint32_t cnt, mcnt, rcnt, sz;
28790da2b28SAriff Abdullah 	int passthrough;
28890da2b28SAriff Abdullah 	uint8_t *tmp;
28990da2b28SAriff Abdullah 
29090da2b28SAriff Abdullah 	if (c->direction == PCMDIR_REC)
29190da2b28SAriff Abdullah 		return (feed_mixer_rec(c));
29290da2b28SAriff Abdullah 
29390da2b28SAriff Abdullah 	sz = sndbuf_getsize(src);
29490da2b28SAriff Abdullah 	if (sz < count)
29590da2b28SAriff Abdullah 		count = sz;
29690da2b28SAriff Abdullah 
29790da2b28SAriff Abdullah 	info = &feed_mixer_info_tab[FEEDMIXER_INFOIDX(f->data)];
29890da2b28SAriff Abdullah 	sz = info->bps * FEEDMIXER_CHANNELS(f->data);
29990da2b28SAriff Abdullah 	count = SND_FXROUND(count, sz);
30090da2b28SAriff Abdullah 	if (count < sz)
30190da2b28SAriff Abdullah 		return (0);
30290da2b28SAriff Abdullah 
30390da2b28SAriff Abdullah 	/*
30490da2b28SAriff Abdullah 	 * We are going to use our source as a temporary buffer since it's
30590da2b28SAriff Abdullah 	 * got no other purpose.  We obtain our data by traversing the channel
30690da2b28SAriff Abdullah 	 * list of children and calling mixer function to mix count bytes from
30790da2b28SAriff Abdullah 	 * each into our destination buffer, b.
30890da2b28SAriff Abdullah 	 */
30990da2b28SAriff Abdullah 	tmp = sndbuf_getbuf(src);
31090da2b28SAriff Abdullah 	rcnt = 0;
31190da2b28SAriff Abdullah 	mcnt = 0;
31290da2b28SAriff Abdullah 	passthrough = 0;	/* 'passthrough' / 'exclusive' marker */
31390da2b28SAriff Abdullah 
31490da2b28SAriff Abdullah 	CHN_FOREACH(ch, c, children.busy) {
31590da2b28SAriff Abdullah 		CHN_LOCK(ch);
31690da2b28SAriff Abdullah 		if (CHN_STOPPED(ch) || (ch->flags & CHN_F_DIRTY)) {
31790da2b28SAriff Abdullah 			CHN_UNLOCK(ch);
31890da2b28SAriff Abdullah 			continue;
31990da2b28SAriff Abdullah 		}
32090da2b28SAriff Abdullah #ifdef SND_DEBUG
32190da2b28SAriff Abdullah 		if ((c->flags & CHN_F_DIRTY) && VCHAN_SYNC_REQUIRED(ch)) {
32290da2b28SAriff Abdullah 			if (vchan_sync(ch) != 0) {
32390da2b28SAriff Abdullah 				CHN_UNLOCK(ch);
32490da2b28SAriff Abdullah 				continue;
32590da2b28SAriff Abdullah 			}
32690da2b28SAriff Abdullah 		}
32790da2b28SAriff Abdullah #endif
32890da2b28SAriff Abdullah 		if ((ch->flags & CHN_F_MMAP) && !(ch->flags & CHN_F_CLOSING))
32990da2b28SAriff Abdullah 			sndbuf_acquire(ch->bufsoft, NULL,
33090da2b28SAriff Abdullah 			    sndbuf_getfree(ch->bufsoft));
33190da2b28SAriff Abdullah 		if (info->mix == NULL) {
33290da2b28SAriff Abdullah 			/*
33390da2b28SAriff Abdullah 			 * Passthrough. Dump the first digital/passthrough
33490da2b28SAriff Abdullah 			 * channel into destination buffer, and the rest into
33590da2b28SAriff Abdullah 			 * nothingness (mute effect).
33690da2b28SAriff Abdullah 			 */
33790da2b28SAriff Abdullah 			if (passthrough == 0 &&
33890da2b28SAriff Abdullah 			    (ch->format & AFMT_PASSTHROUGH)) {
33990da2b28SAriff Abdullah 				rcnt = SND_FXROUND(FEEDER_FEED(ch->feeder, ch,
34090da2b28SAriff Abdullah 				    b, count, ch->bufsoft), sz);
34190da2b28SAriff Abdullah 				passthrough = 1;
34290da2b28SAriff Abdullah 			} else
34390da2b28SAriff Abdullah 				FEEDER_FEED(ch->feeder, ch, tmp, count,
34490da2b28SAriff Abdullah 				    ch->bufsoft);
34590da2b28SAriff Abdullah 		} else if (c->flags & CHN_F_EXCLUSIVE) {
34690da2b28SAriff Abdullah 			/*
34790da2b28SAriff Abdullah 			 * Exclusive. Dump the first 'exclusive' channel into
34890da2b28SAriff Abdullah 			 * destination buffer, and the rest into nothingness
34990da2b28SAriff Abdullah 			 * (mute effect).
35090da2b28SAriff Abdullah 			 */
35190da2b28SAriff Abdullah 			if (passthrough == 0 && (ch->flags & CHN_F_EXCLUSIVE)) {
35290da2b28SAriff Abdullah 				rcnt = SND_FXROUND(FEEDER_FEED(ch->feeder, ch,
35390da2b28SAriff Abdullah 				    b, count, ch->bufsoft), sz);
35490da2b28SAriff Abdullah 				passthrough = 1;
35590da2b28SAriff Abdullah 			} else
35690da2b28SAriff Abdullah 				FEEDER_FEED(ch->feeder, ch, tmp, count,
35790da2b28SAriff Abdullah 				    ch->bufsoft);
35890da2b28SAriff Abdullah 		} else {
35990da2b28SAriff Abdullah 			if (rcnt == 0) {
36090da2b28SAriff Abdullah 				rcnt = SND_FXROUND(FEEDER_FEED(ch->feeder, ch,
36190da2b28SAriff Abdullah 				    b, count, ch->bufsoft), sz);
36290da2b28SAriff Abdullah 				mcnt = count - rcnt;
36390da2b28SAriff Abdullah 			} else {
36490da2b28SAriff Abdullah 				cnt = SND_FXROUND(FEEDER_FEED(ch->feeder, ch,
36590da2b28SAriff Abdullah 				    tmp, count, ch->bufsoft), sz);
36690da2b28SAriff Abdullah 				if (cnt != 0) {
36790da2b28SAriff Abdullah 					if (mcnt != 0) {
36890da2b28SAriff Abdullah 						memset(b + rcnt,
36990da2b28SAriff Abdullah 						    sndbuf_zerodata(
37090da2b28SAriff Abdullah 						    f->desc->out), mcnt);
37190da2b28SAriff Abdullah 						mcnt = 0;
37290da2b28SAriff Abdullah 					}
37390da2b28SAriff Abdullah 					info->mix(tmp, b, cnt);
37490da2b28SAriff Abdullah 					if (cnt > rcnt)
37590da2b28SAriff Abdullah 						rcnt = cnt;
37690da2b28SAriff Abdullah 				}
37790da2b28SAriff Abdullah 			}
37890da2b28SAriff Abdullah 		}
37990da2b28SAriff Abdullah 		CHN_UNLOCK(ch);
38090da2b28SAriff Abdullah 	}
38190da2b28SAriff Abdullah 
38290da2b28SAriff Abdullah 	if (++c->feedcount == 0)
38390da2b28SAriff Abdullah 		c->feedcount = 2;
38490da2b28SAriff Abdullah 
38590da2b28SAriff Abdullah 	c->flags &= ~CHN_F_DIRTY;
38690da2b28SAriff Abdullah 
38790da2b28SAriff Abdullah 	return (rcnt);
38890da2b28SAriff Abdullah }
38990da2b28SAriff Abdullah 
39090da2b28SAriff Abdullah static struct pcm_feederdesc feeder_mixer_desc[] = {
39190da2b28SAriff Abdullah 	{ FEEDER_MIXER, 0, 0, 0, 0 },
39290da2b28SAriff Abdullah 	{ 0, 0, 0, 0, 0 }
39390da2b28SAriff Abdullah };
39490da2b28SAriff Abdullah 
39590da2b28SAriff Abdullah static kobj_method_t feeder_mixer_methods[] = {
39690da2b28SAriff Abdullah 	KOBJMETHOD(feeder_init,		feed_mixer_init),
39790da2b28SAriff Abdullah 	KOBJMETHOD(feeder_set,		feed_mixer_set),
39890da2b28SAriff Abdullah 	KOBJMETHOD(feeder_feed,		feed_mixer_feed),
39990da2b28SAriff Abdullah 	KOBJMETHOD_END
40090da2b28SAriff Abdullah };
40190da2b28SAriff Abdullah 
40290da2b28SAriff Abdullah FEEDER_DECLARE(feeder_mixer, NULL);
403