xref: /freebsd/sys/dev/sound/pcm/feeder_matrix.c (revision 595e514d0df2bac5b813d35f83e32875dbf16a83)
1 /*-
2  * Copyright (c) 2008-2009 Ariff Abdullah <ariff@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 /*
28  * feeder_matrix: Generic any-to-any channel matrixing. Probably not the
29  *                accurate way of doing things, but it should be fast and
30  *                transparent enough, not to mention capable of handling
31  *                possible non-standard way of multichannel interleaving
32  *                order. In other words, it is tough to break.
33  *
34  * The Good:
35  * + very generic and compact, provided that the supplied matrix map is in a
36  *   sane form.
37  * + should be fast enough.
38  *
39  * The Bad:
40  * + somebody might disagree with it.
41  * + 'matrix' is kind of 0x7a69, due to prolong mental block.
42  */
43 
44 #ifdef _KERNEL
45 #ifdef HAVE_KERNEL_OPTION_HEADERS
46 #include "opt_snd.h"
47 #endif
48 #include <dev/sound/pcm/sound.h>
49 #include <dev/sound/pcm/pcm.h>
50 #include "feeder_if.h"
51 
52 #define SND_USE_FXDIV
53 #include "snd_fxdiv_gen.h"
54 
55 SND_DECLARE_FILE("$FreeBSD$");
56 #endif
57 
58 #define FEEDMATRIX_RESERVOIR	(SND_CHN_MAX * PCM_32_BPS)
59 
60 #define SND_CHN_T_EOF		0x00e0fe0f
61 #define SND_CHN_T_NULL		0x0e0e0e0e
62 
63 struct feed_matrix_info;
64 
65 typedef void (*feed_matrix_t)(struct feed_matrix_info *, uint8_t *,
66     uint8_t *, uint32_t);
67 
68 struct feed_matrix_info {
69 	uint32_t bps;
70 	uint32_t ialign, oalign;
71 	uint32_t in, out;
72 	feed_matrix_t apply;
73 #ifdef FEEDMATRIX_GENERIC
74 	intpcm_read_t *rd;
75 	intpcm_write_t *wr;
76 #endif
77 	struct {
78 		int chn[SND_CHN_T_MAX + 1];
79 		int mul, shift;
80 	} matrix[SND_CHN_T_MAX + 1];
81 	uint8_t reservoir[FEEDMATRIX_RESERVOIR];
82 };
83 
84 static struct pcmchan_matrix feeder_matrix_maps[SND_CHN_MATRIX_MAX] = {
85 	[SND_CHN_MATRIX_1_0] = SND_CHN_MATRIX_MAP_1_0,
86 	[SND_CHN_MATRIX_2_0] = SND_CHN_MATRIX_MAP_2_0,
87 	[SND_CHN_MATRIX_2_1] = SND_CHN_MATRIX_MAP_2_1,
88 	[SND_CHN_MATRIX_3_0] = SND_CHN_MATRIX_MAP_3_0,
89 	[SND_CHN_MATRIX_3_1] = SND_CHN_MATRIX_MAP_3_1,
90 	[SND_CHN_MATRIX_4_0] = SND_CHN_MATRIX_MAP_4_0,
91 	[SND_CHN_MATRIX_4_1] = SND_CHN_MATRIX_MAP_4_1,
92 	[SND_CHN_MATRIX_5_0] = SND_CHN_MATRIX_MAP_5_0,
93 	[SND_CHN_MATRIX_5_1] = SND_CHN_MATRIX_MAP_5_1,
94 	[SND_CHN_MATRIX_6_0] = SND_CHN_MATRIX_MAP_6_0,
95 	[SND_CHN_MATRIX_6_1] = SND_CHN_MATRIX_MAP_6_1,
96 	[SND_CHN_MATRIX_7_0] = SND_CHN_MATRIX_MAP_7_0,
97 	[SND_CHN_MATRIX_7_1] = SND_CHN_MATRIX_MAP_7_1
98 };
99 
100 static int feeder_matrix_default_ids[9] = {
101 	[0] = SND_CHN_MATRIX_UNKNOWN,
102 	[1] = SND_CHN_MATRIX_1,
103 	[2] = SND_CHN_MATRIX_2,
104 	[3] = SND_CHN_MATRIX_3,
105 	[4] = SND_CHN_MATRIX_4,
106 	[5] = SND_CHN_MATRIX_5,
107 	[6] = SND_CHN_MATRIX_6,
108 	[7] = SND_CHN_MATRIX_7,
109 	[8] = SND_CHN_MATRIX_8
110 };
111 
112 #ifdef _KERNEL
113 #define FEEDMATRIX_CLIP_CHECK(...)
114 #else
115 #define FEEDMATRIX_CLIP_CHECK(v, BIT)	do {				\
116 	if ((v) < PCM_S##BIT##_MIN || (v) > PCM_S##BIT##_MAX)		\
117 	    errx(1, "\n\n%s(): Sample clipping: %jd\n",			\
118 		__func__, (intmax_t)(v));				\
119 } while (0)
120 #endif
121 
122 #define FEEDMATRIX_DECLARE(SIGN, BIT, ENDIAN)				\
123 static void								\
124 feed_matrix_##SIGN##BIT##ENDIAN(struct feed_matrix_info *info,		\
125     uint8_t *src, uint8_t *dst, uint32_t count)				\
126 {									\
127 	intpcm64_t accum;						\
128 	intpcm_t v;							\
129 	int i, j;							\
130 									\
131 	do {								\
132 		for (i = 0; info->matrix[i].chn[0] != SND_CHN_T_EOF;	\
133 		    i++) {						\
134 			if (info->matrix[i].chn[0] == SND_CHN_T_NULL) {	\
135 				_PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst,	\
136 				    0);					\
137 				dst += PCM_##BIT##_BPS;			\
138 				continue;				\
139 			} else if (info->matrix[i].chn[1] ==		\
140 			    SND_CHN_T_EOF) {				\
141 				v = _PCM_READ_##SIGN##BIT##_##ENDIAN(	\
142 				    src + info->matrix[i].chn[0]);	\
143 				_PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst,	\
144 				    v);					\
145 				dst += PCM_##BIT##_BPS;			\
146 				continue;				\
147 			}						\
148 									\
149 			accum = 0;					\
150 			for (j = 0;					\
151 			    info->matrix[i].chn[j] != SND_CHN_T_EOF;	\
152 			    j++) {					\
153 				v = _PCM_READ_##SIGN##BIT##_##ENDIAN(	\
154 				    src + info->matrix[i].chn[j]);	\
155 				accum += v;				\
156 			}						\
157 									\
158 			accum = (accum * info->matrix[i].mul) >>	\
159 			    info->matrix[i].shift;			\
160 									\
161 			FEEDMATRIX_CLIP_CHECK(accum, BIT);		\
162 									\
163 			v = (accum > PCM_S##BIT##_MAX) ?		\
164 			    PCM_S##BIT##_MAX :				\
165 			    ((accum < PCM_S##BIT##_MIN) ?		\
166 			    PCM_S##BIT##_MIN :				\
167 			    accum);					\
168 			_PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst, v);	\
169 			dst += PCM_##BIT##_BPS;				\
170 		}							\
171 		src += info->ialign;					\
172 	} while (--count != 0);						\
173 }
174 
175 #if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
176 FEEDMATRIX_DECLARE(S, 16, LE)
177 FEEDMATRIX_DECLARE(S, 32, LE)
178 #endif
179 #if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
180 FEEDMATRIX_DECLARE(S, 16, BE)
181 FEEDMATRIX_DECLARE(S, 32, BE)
182 #endif
183 #ifdef SND_FEEDER_MULTIFORMAT
184 FEEDMATRIX_DECLARE(S,  8, NE)
185 FEEDMATRIX_DECLARE(S, 24, LE)
186 FEEDMATRIX_DECLARE(S, 24, BE)
187 FEEDMATRIX_DECLARE(U,  8, NE)
188 FEEDMATRIX_DECLARE(U, 16, LE)
189 FEEDMATRIX_DECLARE(U, 24, LE)
190 FEEDMATRIX_DECLARE(U, 32, LE)
191 FEEDMATRIX_DECLARE(U, 16, BE)
192 FEEDMATRIX_DECLARE(U, 24, BE)
193 FEEDMATRIX_DECLARE(U, 32, BE)
194 #endif
195 
196 #define FEEDMATRIX_ENTRY(SIGN, BIT, ENDIAN)				\
197 	{								\
198 		AFMT_##SIGN##BIT##_##ENDIAN,				\
199 		feed_matrix_##SIGN##BIT##ENDIAN				\
200 	}
201 
202 static const struct {
203 	uint32_t format;
204 	feed_matrix_t apply;
205 } feed_matrix_tab[] = {
206 #if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
207 	FEEDMATRIX_ENTRY(S, 16, LE),
208 	FEEDMATRIX_ENTRY(S, 32, LE),
209 #endif
210 #if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
211 	FEEDMATRIX_ENTRY(S, 16, BE),
212 	FEEDMATRIX_ENTRY(S, 32, BE),
213 #endif
214 #ifdef SND_FEEDER_MULTIFORMAT
215 	FEEDMATRIX_ENTRY(S,  8, NE),
216 	FEEDMATRIX_ENTRY(S, 24, LE),
217 	FEEDMATRIX_ENTRY(S, 24, BE),
218 	FEEDMATRIX_ENTRY(U,  8, NE),
219 	FEEDMATRIX_ENTRY(U, 16, LE),
220 	FEEDMATRIX_ENTRY(U, 24, LE),
221 	FEEDMATRIX_ENTRY(U, 32, LE),
222 	FEEDMATRIX_ENTRY(U, 16, BE),
223 	FEEDMATRIX_ENTRY(U, 24, BE),
224 	FEEDMATRIX_ENTRY(U, 32, BE)
225 #endif
226 };
227 
228 static void
229 feed_matrix_reset(struct feed_matrix_info *info)
230 {
231 	uint32_t i, j;
232 
233 	for (i = 0; i < (sizeof(info->matrix) / sizeof(info->matrix[0])); i++) {
234 		for (j = 0;
235 		    j < (sizeof(info->matrix[i].chn) /
236 		    sizeof(info->matrix[i].chn[0])); j++) {
237 			info->matrix[i].chn[j] = SND_CHN_T_EOF;
238 		}
239 		info->matrix[i].mul   = 1;
240 		info->matrix[i].shift = 0;
241 	}
242 }
243 
244 #ifdef FEEDMATRIX_GENERIC
245 static void
246 feed_matrix_apply_generic(struct feed_matrix_info *info,
247     uint8_t *src, uint8_t *dst, uint32_t count)
248 {
249 	intpcm64_t accum;
250 	intpcm_t v;
251 	int i, j;
252 
253 	do {
254 		for (i = 0; info->matrix[i].chn[0] != SND_CHN_T_EOF;
255 		    i++) {
256 			if (info->matrix[i].chn[0] == SND_CHN_T_NULL) {
257 				info->wr(dst, 0);
258 				dst += info->bps;
259 				continue;
260 			} else if (info->matrix[i].chn[1] ==
261 			    SND_CHN_T_EOF) {
262 				v = info->rd(src + info->matrix[i].chn[0]);
263 				info->wr(dst, v);
264 				dst += info->bps;
265 				continue;
266 			}
267 
268 			accum = 0;
269 			for (j = 0;
270 			    info->matrix[i].chn[j] != SND_CHN_T_EOF;
271 			    j++) {
272 				v = info->rd(src + info->matrix[i].chn[j]);
273 				accum += v;
274 			}
275 
276 			accum = (accum * info->matrix[i].mul) >>
277 			    info->matrix[i].shift;
278 
279 			FEEDMATRIX_CLIP_CHECK(accum, 32);
280 
281 			v = (accum > PCM_S32_MAX) ? PCM_S32_MAX :
282 			    ((accum < PCM_S32_MIN) ? PCM_S32_MIN : accum);
283 			info->wr(dst, v);
284 			dst += info->bps;
285 		}
286 		src += info->ialign;
287 	} while (--count != 0);
288 }
289 #endif
290 
291 static int
292 feed_matrix_setup(struct feed_matrix_info *info, struct pcmchan_matrix *m_in,
293     struct pcmchan_matrix *m_out)
294 {
295 	uint32_t i, j, ch, in_mask, merge_mask;
296 	int mul, shift;
297 
298 
299 	if (info == NULL || m_in == NULL || m_out == NULL ||
300 	    AFMT_CHANNEL(info->in) != m_in->channels ||
301 	    AFMT_CHANNEL(info->out) != m_out->channels ||
302 	    m_in->channels < SND_CHN_MIN || m_in->channels > SND_CHN_MAX ||
303 	    m_out->channels < SND_CHN_MIN || m_out->channels > SND_CHN_MAX)
304 		return (EINVAL);
305 
306 	feed_matrix_reset(info);
307 
308 	/*
309 	 * If both in and out are part of standard matrix and identical, skip
310 	 * everything alltogether.
311 	 */
312 	if (m_in->id == m_out->id && !(m_in->id < SND_CHN_MATRIX_BEGIN ||
313 	    m_in->id > SND_CHN_MATRIX_END))
314 		return (0);
315 
316 	/*
317 	 * Special case for mono input matrix. If the output supports
318 	 * possible 'center' channel, route it there. Otherwise, let it be
319 	 * matrixed to left/right.
320 	 */
321 	if (m_in->id == SND_CHN_MATRIX_1_0) {
322 		if (m_out->id == SND_CHN_MATRIX_1_0)
323 			in_mask = SND_CHN_T_MASK_FL;
324 		else if (m_out->mask & SND_CHN_T_MASK_FC)
325 			in_mask = SND_CHN_T_MASK_FC;
326 		else
327 			in_mask = SND_CHN_T_MASK_FL | SND_CHN_T_MASK_FR;
328 	} else
329 		in_mask = m_in->mask;
330 
331 	/* Merge, reduce, expand all possibilites. */
332 	for (ch = SND_CHN_T_BEGIN; ch <= SND_CHN_T_END &&
333 	    m_out->map[ch].type != SND_CHN_T_MAX; ch += SND_CHN_T_STEP) {
334 		merge_mask = m_out->map[ch].members & in_mask;
335 		if (merge_mask == 0) {
336 			info->matrix[ch].chn[0] = SND_CHN_T_NULL;
337 			continue;
338 		}
339 
340 		j = 0;
341 		for (i = SND_CHN_T_BEGIN; i <= SND_CHN_T_END;
342 		    i += SND_CHN_T_STEP) {
343 			if (merge_mask & (1 << i)) {
344 				if (m_in->offset[i] >= 0 &&
345 				    m_in->offset[i] < (int)m_in->channels)
346 					info->matrix[ch].chn[j++] =
347 					    m_in->offset[i] * info->bps;
348 				else {
349 					info->matrix[ch].chn[j++] =
350 					    SND_CHN_T_EOF;
351 					break;
352 				}
353 			}
354 		}
355 
356 #define FEEDMATRIX_ATTN_SHIFT	16
357 
358 		if (j > 1) {
359 			/*
360 			 * XXX For channel that require accumulation from
361 			 * multiple channels, apply a slight attenuation to
362 			 * avoid clipping.
363 			 */
364 			mul   = (1 << (FEEDMATRIX_ATTN_SHIFT - 1)) + 143 - j;
365 			shift = FEEDMATRIX_ATTN_SHIFT;
366 			while ((mul & 1) == 0 && shift > 0) {
367 				mul >>= 1;
368 				shift--;
369 			}
370 			info->matrix[ch].mul   = mul;
371 			info->matrix[ch].shift = shift;
372 		}
373 	}
374 
375 #ifndef _KERNEL
376 	fprintf(stderr, "Total: %d\n", ch);
377 
378 	for (i = 0; info->matrix[i].chn[0] != SND_CHN_T_EOF; i++) {
379 		fprintf(stderr, "%d: [", i);
380 		for (j = 0; info->matrix[i].chn[j] != SND_CHN_T_EOF; j++) {
381 			if (j != 0)
382 				fprintf(stderr, ", ");
383 			fprintf(stderr, "%d",
384 			    (info->matrix[i].chn[j] == SND_CHN_T_NULL) ?
385 			    0xffffffff : info->matrix[i].chn[j] / info->bps);
386 		}
387 		fprintf(stderr, "] attn: (x * %d) >> %d\n",
388 		    info->matrix[i].mul, info->matrix[i].shift);
389 	}
390 #endif
391 
392 	return (0);
393 }
394 
395 static int
396 feed_matrix_init(struct pcm_feeder *f)
397 {
398 	struct feed_matrix_info *info;
399 	struct pcmchan_matrix *m_in, *m_out;
400 	uint32_t i;
401 	int ret;
402 
403 	if (AFMT_ENCODING(f->desc->in) != AFMT_ENCODING(f->desc->out))
404 		return (EINVAL);
405 
406 	info = malloc(sizeof(*info), M_DEVBUF, M_NOWAIT | M_ZERO);
407 	if (info == NULL)
408 		return (ENOMEM);
409 
410 	info->in = f->desc->in;
411 	info->out = f->desc->out;
412 	info->bps = AFMT_BPS(info->in);
413 	info->ialign = AFMT_ALIGN(info->in);
414 	info->oalign = AFMT_ALIGN(info->out);
415 	info->apply = NULL;
416 
417 	for (i = 0; info->apply == NULL &&
418 	    i < (sizeof(feed_matrix_tab) / sizeof(feed_matrix_tab[0])); i++) {
419 		if (AFMT_ENCODING(info->in) == feed_matrix_tab[i].format)
420 			info->apply = feed_matrix_tab[i].apply;
421 	}
422 
423 	if (info->apply == NULL) {
424 #ifdef FEEDMATRIX_GENERIC
425 		info->rd = feeder_format_read_op(info->in);
426 		info->wr = feeder_format_write_op(info->out);
427 		if (info->rd == NULL || info->wr == NULL) {
428 			free(info, M_DEVBUF);
429 			return (EINVAL);
430 		}
431 		info->apply = feed_matrix_apply_generic;
432 #else
433 		free(info, M_DEVBUF);
434 		return (EINVAL);
435 #endif
436 	}
437 
438 	m_in  = feeder_matrix_format_map(info->in);
439 	m_out = feeder_matrix_format_map(info->out);
440 
441 	ret = feed_matrix_setup(info, m_in, m_out);
442 	if (ret != 0) {
443 		free(info, M_DEVBUF);
444 		return (ret);
445 	}
446 
447 	f->data = info;
448 
449 	return (0);
450 }
451 
452 static int
453 feed_matrix_free(struct pcm_feeder *f)
454 {
455 	struct feed_matrix_info *info;
456 
457 	info = f->data;
458 	if (info != NULL)
459 		free(info, M_DEVBUF);
460 
461 	f->data = NULL;
462 
463 	return (0);
464 }
465 
466 static int
467 feed_matrix_feed(struct pcm_feeder *f, struct pcm_channel *c, uint8_t *b,
468     uint32_t count, void *source)
469 {
470 	struct feed_matrix_info *info;
471 	uint32_t j, inmax;
472 	uint8_t *src, *dst;
473 
474 	info = f->data;
475 	if (info->matrix[0].chn[0] == SND_CHN_T_EOF)
476 		return (FEEDER_FEED(f->source, c, b, count, source));
477 
478 	dst = b;
479 	count = SND_FXROUND(count, info->oalign);
480 	inmax = info->ialign + info->oalign;
481 
482 	/*
483 	 * This loop might look simmilar to other feeder_* loops, but be
484 	 * advised: matrixing might involve overlapping (think about
485 	 * swapping end to front or something like that). In this regard it
486 	 * might be simmilar to feeder_format, but feeder_format works on
487 	 * 'sample' domain where it can be fitted into single 32bit integer
488 	 * while matrixing works on 'sample frame' domain.
489 	 */
490 	do {
491 		if (count < info->oalign)
492 			break;
493 
494 		if (count < inmax) {
495 			src = info->reservoir;
496 			j = info->ialign;
497 		} else {
498 			if (info->ialign == info->oalign)
499 				j = count - info->oalign;
500 			else if (info->ialign > info->oalign)
501 				j = SND_FXROUND(count - info->oalign,
502 				    info->ialign);
503 			else
504 				j = (SND_FXDIV(count, info->oalign) - 1) *
505 				    info->ialign;
506 			src = dst + count - j;
507 		}
508 
509 		j = SND_FXDIV(FEEDER_FEED(f->source, c, src, j, source),
510 		    info->ialign);
511 		if (j == 0)
512 			break;
513 
514 		info->apply(info, src, dst, j);
515 
516 		j *= info->oalign;
517 		dst += j;
518 		count -= j;
519 
520 	} while (count != 0);
521 
522 	return (dst - b);
523 }
524 
525 static struct pcm_feederdesc feeder_matrix_desc[] = {
526 	{ FEEDER_MATRIX, 0, 0, 0, 0 },
527 	{ 0, 0, 0, 0, 0 }
528 };
529 
530 static kobj_method_t feeder_matrix_methods[] = {
531 	KOBJMETHOD(feeder_init,		feed_matrix_init),
532 	KOBJMETHOD(feeder_free,		feed_matrix_free),
533 	KOBJMETHOD(feeder_feed,		feed_matrix_feed),
534 	KOBJMETHOD_END
535 };
536 
537 FEEDER_DECLARE(feeder_matrix, NULL);
538 
539 /* External */
540 int
541 feeder_matrix_setup(struct pcm_feeder *f, struct pcmchan_matrix *m_in,
542     struct pcmchan_matrix *m_out)
543 {
544 
545 	if (f == NULL || f->desc == NULL || f->desc->type != FEEDER_MATRIX ||
546 	    f->data == NULL)
547 		return (EINVAL);
548 
549 	return (feed_matrix_setup(f->data, m_in, m_out));
550 }
551 
552 /*
553  * feeder_matrix_default_id(): For a given number of channels, return
554  *                             default prefered id (example: both 5.1 and
555  *                             6.0 are simply 6 channels, but 5.1 is more
556  *                             preferable).
557  */
558 int
559 feeder_matrix_default_id(uint32_t ch)
560 {
561 
562 	if (ch < feeder_matrix_maps[SND_CHN_MATRIX_BEGIN].channels ||
563 	    ch > feeder_matrix_maps[SND_CHN_MATRIX_END].channels)
564 		return (SND_CHN_MATRIX_UNKNOWN);
565 
566 	return (feeder_matrix_maps[feeder_matrix_default_ids[ch]].id);
567 }
568 
569 /*
570  * feeder_matrix_default_channel_map(): Ditto, but return matrix map
571  *                                      instead.
572  */
573 struct pcmchan_matrix *
574 feeder_matrix_default_channel_map(uint32_t ch)
575 {
576 
577 	if (ch < feeder_matrix_maps[SND_CHN_MATRIX_BEGIN].channels ||
578 	    ch > feeder_matrix_maps[SND_CHN_MATRIX_END].channels)
579 		return (NULL);
580 
581 	return (&feeder_matrix_maps[feeder_matrix_default_ids[ch]]);
582 }
583 
584 /*
585  * feeder_matrix_default_format(): For a given audio format, return the
586  *                                 proper audio format based on preferable
587  *                                 matrix.
588  */
589 uint32_t
590 feeder_matrix_default_format(uint32_t format)
591 {
592 	struct pcmchan_matrix *m;
593 	uint32_t i, ch, ext;
594 
595 	ch = AFMT_CHANNEL(format);
596 	ext = AFMT_EXTCHANNEL(format);
597 
598 	if (ext != 0) {
599 		for (i = SND_CHN_MATRIX_BEGIN; i <= SND_CHN_MATRIX_END; i++) {
600 			if (feeder_matrix_maps[i].channels == ch &&
601 			    feeder_matrix_maps[i].ext == ext)
602 			return (SND_FORMAT(format, ch, ext));
603 		}
604 	}
605 
606 	m = feeder_matrix_default_channel_map(ch);
607 	if (m == NULL)
608 		return (0x00000000);
609 
610 	return (SND_FORMAT(format, ch, m->ext));
611 }
612 
613 /*
614  * feeder_matrix_format_id(): For a given audio format, return its matrix
615  *                            id.
616  */
617 int
618 feeder_matrix_format_id(uint32_t format)
619 {
620 	uint32_t i, ch, ext;
621 
622 	ch = AFMT_CHANNEL(format);
623 	ext = AFMT_EXTCHANNEL(format);
624 
625 	for (i = SND_CHN_MATRIX_BEGIN; i <= SND_CHN_MATRIX_END; i++) {
626 		if (feeder_matrix_maps[i].channels == ch &&
627 		    feeder_matrix_maps[i].ext == ext)
628 			return (feeder_matrix_maps[i].id);
629 	}
630 
631 	return (SND_CHN_MATRIX_UNKNOWN);
632 }
633 
634 /*
635  * feeder_matrix_format_map(): For a given audio format, return its matrix
636  *                             map.
637  */
638 struct pcmchan_matrix *
639 feeder_matrix_format_map(uint32_t format)
640 {
641 	uint32_t i, ch, ext;
642 
643 	ch = AFMT_CHANNEL(format);
644 	ext = AFMT_EXTCHANNEL(format);
645 
646 	for (i = SND_CHN_MATRIX_BEGIN; i <= SND_CHN_MATRIX_END; i++) {
647 		if (feeder_matrix_maps[i].channels == ch &&
648 		    feeder_matrix_maps[i].ext == ext)
649 			return (&feeder_matrix_maps[i]);
650 	}
651 
652 	return (NULL);
653 }
654 
655 /*
656  * feeder_matrix_id_map(): For a given matrix id, return its matrix map.
657  */
658 struct pcmchan_matrix *
659 feeder_matrix_id_map(int id)
660 {
661 
662 	if (id < SND_CHN_MATRIX_BEGIN || id > SND_CHN_MATRIX_END)
663 		return (NULL);
664 
665 	return (&feeder_matrix_maps[id]);
666 }
667 
668 /*
669  * feeder_matrix_compare(): Compare the simmilarities of matrices.
670  */
671 int
672 feeder_matrix_compare(struct pcmchan_matrix *m_in, struct pcmchan_matrix *m_out)
673 {
674 	uint32_t i;
675 
676 	if (m_in == m_out)
677 		return (0);
678 
679 	if (m_in->channels != m_out->channels || m_in->ext != m_out->ext ||
680 	    m_in->mask != m_out->mask)
681 		return (1);
682 
683 	for (i = 0; i < (sizeof(m_in->map) / sizeof(m_in->map[0])); i++) {
684 		if (m_in->map[i].type != m_out->map[i].type)
685 			return (1);
686 		if (m_in->map[i].type == SND_CHN_T_MAX)
687 			break;
688 		if (m_in->map[i].members != m_out->map[i].members)
689 			return (1);
690 		if (i <= SND_CHN_T_END) {
691 			if (m_in->offset[m_in->map[i].type] !=
692 			    m_out->offset[m_out->map[i].type])
693 				return (1);
694 		}
695 	}
696 
697 	return (0);
698 }
699 
700 /*
701  * XXX 4front intepretation of "surround" is ambigous and sort of
702  *     conflicting with "rear"/"back". Map it to "side". Well..
703  *     who cares?
704  */
705 static int snd_chn_to_oss[SND_CHN_T_MAX] = {
706 	[SND_CHN_T_FL] = CHID_L,
707 	[SND_CHN_T_FR] = CHID_R,
708 	[SND_CHN_T_FC] = CHID_C,
709 	[SND_CHN_T_LF] = CHID_LFE,
710 	[SND_CHN_T_SL] = CHID_LS,
711 	[SND_CHN_T_SR] = CHID_RS,
712 	[SND_CHN_T_BL] = CHID_LR,
713 	[SND_CHN_T_BR] = CHID_RR
714 };
715 
716 #define SND_CHN_OSS_VALIDMASK						\
717 			(SND_CHN_T_MASK_FL | SND_CHN_T_MASK_FR |	\
718 			 SND_CHN_T_MASK_FC | SND_CHN_T_MASK_LF |	\
719 			 SND_CHN_T_MASK_SL | SND_CHN_T_MASK_SR |	\
720 			 SND_CHN_T_MASK_BL | SND_CHN_T_MASK_BR)
721 
722 #define SND_CHN_OSS_MAX		8
723 #define SND_CHN_OSS_BEGIN	CHID_L
724 #define SND_CHN_OSS_END		CHID_RR
725 
726 static int oss_to_snd_chn[SND_CHN_OSS_END + 1] = {
727 	[CHID_L]   = SND_CHN_T_FL,
728 	[CHID_R]   = SND_CHN_T_FR,
729 	[CHID_C]   = SND_CHN_T_FC,
730 	[CHID_LFE] = SND_CHN_T_LF,
731 	[CHID_LS]  = SND_CHN_T_SL,
732 	[CHID_RS]  = SND_CHN_T_SR,
733 	[CHID_LR]  = SND_CHN_T_BL,
734 	[CHID_RR]  = SND_CHN_T_BR
735 };
736 
737 /*
738  * Used by SNDCTL_DSP_GET_CHNORDER.
739  */
740 int
741 feeder_matrix_oss_get_channel_order(struct pcmchan_matrix *m,
742     unsigned long long *map)
743 {
744 	unsigned long long tmpmap;
745 	uint32_t i;
746 
747 	if (m == NULL || map == NULL || (m->mask & ~SND_CHN_OSS_VALIDMASK) ||
748 	    m->channels > SND_CHN_OSS_MAX)
749 		return (EINVAL);
750 
751 	tmpmap = 0x0000000000000000ULL;
752 
753 	for (i = 0; m->map[i].type != SND_CHN_T_MAX &&
754 	    i < SND_CHN_OSS_MAX; i++) {
755 		if ((1 << m->map[i].type) & ~SND_CHN_OSS_VALIDMASK)
756 			return (EINVAL);
757 		tmpmap |=
758 		    (unsigned long long)snd_chn_to_oss[m->map[i].type] <<
759 		    (i * 4);
760 	}
761 
762 	*map = tmpmap;
763 
764 	return (0);
765 }
766 
767 /*
768  * Used by SNDCTL_DSP_SET_CHNORDER.
769  */
770 int
771 feeder_matrix_oss_set_channel_order(struct pcmchan_matrix *m,
772     unsigned long long *map)
773 {
774 	struct pcmchan_matrix tmp;
775 	uint32_t chmask, i;
776 	int ch, cheof;
777 
778 	if (m == NULL || map == NULL || (m->mask & ~SND_CHN_OSS_VALIDMASK) ||
779 	    m->channels > SND_CHN_OSS_MAX || (*map & 0xffffffff00000000ULL))
780 		return (EINVAL);
781 
782 	tmp = *m;
783 	tmp.channels = 0;
784 	tmp.ext = 0;
785 	tmp.mask = 0;
786 	memset(tmp.offset, -1, sizeof(tmp.offset));
787 	cheof = 0;
788 
789 	for (i = 0; i < SND_CHN_OSS_MAX; i++) {
790 		ch = (*map >> (i * 4)) & 0xf;
791 		if (ch < SND_CHN_OSS_BEGIN) {
792 			if (cheof == 0 && m->map[i].type != SND_CHN_T_MAX)
793 				return (EINVAL);
794 			cheof++;
795 			tmp.map[i] = m->map[i];
796 			continue;
797 		} else if (ch > SND_CHN_OSS_END)
798 			return (EINVAL);
799 		else if (cheof != 0)
800 			return (EINVAL);
801 		ch = oss_to_snd_chn[ch];
802 		chmask = 1 << ch;
803 		/* channel not exist in matrix */
804 		if (!(chmask & m->mask))
805 			return (EINVAL);
806 		/* duplicated channel */
807 		if (chmask & tmp.mask)
808 			return (EINVAL);
809 		tmp.map[i] = m->map[m->offset[ch]];
810 		if (tmp.map[i].type != ch)
811 			return (EINVAL);
812 		tmp.offset[ch] = i;
813 		tmp.mask |= chmask;
814 		tmp.channels++;
815 		if (chmask & SND_CHN_T_MASK_LF)
816 			tmp.ext++;
817 	}
818 
819 	if (tmp.channels != m->channels || tmp.ext != m->ext ||
820 	    tmp.mask != m->mask ||
821 	    tmp.map[m->channels].type != SND_CHN_T_MAX)
822 		return (EINVAL);
823 
824 	*m = tmp;
825 
826 	return (0);
827 }
828