xref: /freebsd/sys/dev/sound/pcm/feeder_matrix.c (revision 43a5ec4eb41567cc92586503212743d89686d78f)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2008-2009 Ariff Abdullah <ariff@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 /*
30  * feeder_matrix: Generic any-to-any channel matrixing. Probably not the
31  *                accurate way of doing things, but it should be fast and
32  *                transparent enough, not to mention capable of handling
33  *                possible non-standard way of multichannel interleaving
34  *                order. In other words, it is tough to break.
35  *
36  * The Good:
37  * + very generic and compact, provided that the supplied matrix map is in a
38  *   sane form.
39  * + should be fast enough.
40  *
41  * The Bad:
42  * + somebody might disagree with it.
43  * + 'matrix' is kind of 0x7a69, due to prolong mental block.
44  */
45 
46 #ifdef _KERNEL
47 #ifdef HAVE_KERNEL_OPTION_HEADERS
48 #include "opt_snd.h"
49 #endif
50 #include <dev/sound/pcm/sound.h>
51 #include <dev/sound/pcm/pcm.h>
52 #include "feeder_if.h"
53 
54 #define SND_USE_FXDIV
55 #include "snd_fxdiv_gen.h"
56 
57 SND_DECLARE_FILE("$FreeBSD$");
58 #endif
59 
60 #define FEEDMATRIX_RESERVOIR	(SND_CHN_MAX * PCM_32_BPS)
61 
62 #define SND_CHN_T_EOF		0x00e0fe0f
63 #define SND_CHN_T_NULL		0x0e0e0e0e
64 
65 struct feed_matrix_info;
66 
67 typedef void (*feed_matrix_t)(struct feed_matrix_info *, uint8_t *,
68     uint8_t *, uint32_t);
69 
70 struct feed_matrix_info {
71 	uint32_t bps;
72 	uint32_t ialign, oalign;
73 	uint32_t in, out;
74 	feed_matrix_t apply;
75 #ifdef FEEDMATRIX_GENERIC
76 	intpcm_read_t *rd;
77 	intpcm_write_t *wr;
78 #endif
79 	struct {
80 		int chn[SND_CHN_T_MAX + 1];
81 		int mul, shift;
82 	} matrix[SND_CHN_T_MAX + 1];
83 	uint8_t reservoir[FEEDMATRIX_RESERVOIR];
84 };
85 
86 static struct pcmchan_matrix feeder_matrix_maps[SND_CHN_MATRIX_MAX] = {
87 	[SND_CHN_MATRIX_1_0] = SND_CHN_MATRIX_MAP_1_0,
88 	[SND_CHN_MATRIX_2_0] = SND_CHN_MATRIX_MAP_2_0,
89 	[SND_CHN_MATRIX_2_1] = SND_CHN_MATRIX_MAP_2_1,
90 	[SND_CHN_MATRIX_3_0] = SND_CHN_MATRIX_MAP_3_0,
91 	[SND_CHN_MATRIX_3_1] = SND_CHN_MATRIX_MAP_3_1,
92 	[SND_CHN_MATRIX_4_0] = SND_CHN_MATRIX_MAP_4_0,
93 	[SND_CHN_MATRIX_4_1] = SND_CHN_MATRIX_MAP_4_1,
94 	[SND_CHN_MATRIX_5_0] = SND_CHN_MATRIX_MAP_5_0,
95 	[SND_CHN_MATRIX_5_1] = SND_CHN_MATRIX_MAP_5_1,
96 	[SND_CHN_MATRIX_6_0] = SND_CHN_MATRIX_MAP_6_0,
97 	[SND_CHN_MATRIX_6_1] = SND_CHN_MATRIX_MAP_6_1,
98 	[SND_CHN_MATRIX_7_0] = SND_CHN_MATRIX_MAP_7_0,
99 	[SND_CHN_MATRIX_7_1] = SND_CHN_MATRIX_MAP_7_1
100 };
101 
102 static int feeder_matrix_default_ids[9] = {
103 	[0] = SND_CHN_MATRIX_UNKNOWN,
104 	[1] = SND_CHN_MATRIX_1,
105 	[2] = SND_CHN_MATRIX_2,
106 	[3] = SND_CHN_MATRIX_3,
107 	[4] = SND_CHN_MATRIX_4,
108 	[5] = SND_CHN_MATRIX_5,
109 	[6] = SND_CHN_MATRIX_6,
110 	[7] = SND_CHN_MATRIX_7,
111 	[8] = SND_CHN_MATRIX_8
112 };
113 
114 #ifdef _KERNEL
115 #define FEEDMATRIX_CLIP_CHECK(...)
116 #else
117 #define FEEDMATRIX_CLIP_CHECK(v, BIT)	do {				\
118 	if ((v) < PCM_S##BIT##_MIN || (v) > PCM_S##BIT##_MAX)		\
119 	    errx(1, "\n\n%s(): Sample clipping: %jd\n",			\
120 		__func__, (intmax_t)(v));				\
121 } while (0)
122 #endif
123 
124 #define FEEDMATRIX_DECLARE(SIGN, BIT, ENDIAN)				\
125 static void								\
126 feed_matrix_##SIGN##BIT##ENDIAN(struct feed_matrix_info *info,		\
127     uint8_t *src, uint8_t *dst, uint32_t count)				\
128 {									\
129 	intpcm64_t accum;						\
130 	intpcm_t v;							\
131 	int i, j;							\
132 									\
133 	do {								\
134 		for (i = 0; info->matrix[i].chn[0] != SND_CHN_T_EOF;	\
135 		    i++) {						\
136 			if (info->matrix[i].chn[0] == SND_CHN_T_NULL) {	\
137 				_PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst,	\
138 				    0);					\
139 				dst += PCM_##BIT##_BPS;			\
140 				continue;				\
141 			} else if (info->matrix[i].chn[1] ==		\
142 			    SND_CHN_T_EOF) {				\
143 				v = _PCM_READ_##SIGN##BIT##_##ENDIAN(	\
144 				    src + info->matrix[i].chn[0]);	\
145 				_PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst,	\
146 				    v);					\
147 				dst += PCM_##BIT##_BPS;			\
148 				continue;				\
149 			}						\
150 									\
151 			accum = 0;					\
152 			for (j = 0;					\
153 			    info->matrix[i].chn[j] != SND_CHN_T_EOF;	\
154 			    j++) {					\
155 				v = _PCM_READ_##SIGN##BIT##_##ENDIAN(	\
156 				    src + info->matrix[i].chn[j]);	\
157 				accum += v;				\
158 			}						\
159 									\
160 			accum = (accum * info->matrix[i].mul) >>	\
161 			    info->matrix[i].shift;			\
162 									\
163 			FEEDMATRIX_CLIP_CHECK(accum, BIT);		\
164 									\
165 			v = (accum > PCM_S##BIT##_MAX) ?		\
166 			    PCM_S##BIT##_MAX :				\
167 			    ((accum < PCM_S##BIT##_MIN) ?		\
168 			    PCM_S##BIT##_MIN :				\
169 			    accum);					\
170 			_PCM_WRITE_##SIGN##BIT##_##ENDIAN(dst, v);	\
171 			dst += PCM_##BIT##_BPS;				\
172 		}							\
173 		src += info->ialign;					\
174 	} while (--count != 0);						\
175 }
176 
177 #if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
178 FEEDMATRIX_DECLARE(S, 16, LE)
179 FEEDMATRIX_DECLARE(S, 32, LE)
180 #endif
181 #if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
182 FEEDMATRIX_DECLARE(S, 16, BE)
183 FEEDMATRIX_DECLARE(S, 32, BE)
184 #endif
185 #ifdef SND_FEEDER_MULTIFORMAT
186 FEEDMATRIX_DECLARE(S,  8, NE)
187 FEEDMATRIX_DECLARE(S, 24, LE)
188 FEEDMATRIX_DECLARE(S, 24, BE)
189 FEEDMATRIX_DECLARE(U,  8, NE)
190 FEEDMATRIX_DECLARE(U, 16, LE)
191 FEEDMATRIX_DECLARE(U, 24, LE)
192 FEEDMATRIX_DECLARE(U, 32, LE)
193 FEEDMATRIX_DECLARE(U, 16, BE)
194 FEEDMATRIX_DECLARE(U, 24, BE)
195 FEEDMATRIX_DECLARE(U, 32, BE)
196 #endif
197 
198 #define FEEDMATRIX_ENTRY(SIGN, BIT, ENDIAN)				\
199 	{								\
200 		AFMT_##SIGN##BIT##_##ENDIAN,				\
201 		feed_matrix_##SIGN##BIT##ENDIAN				\
202 	}
203 
204 static const struct {
205 	uint32_t format;
206 	feed_matrix_t apply;
207 } feed_matrix_tab[] = {
208 #if BYTE_ORDER == LITTLE_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
209 	FEEDMATRIX_ENTRY(S, 16, LE),
210 	FEEDMATRIX_ENTRY(S, 32, LE),
211 #endif
212 #if BYTE_ORDER == BIG_ENDIAN || defined(SND_FEEDER_MULTIFORMAT)
213 	FEEDMATRIX_ENTRY(S, 16, BE),
214 	FEEDMATRIX_ENTRY(S, 32, BE),
215 #endif
216 #ifdef SND_FEEDER_MULTIFORMAT
217 	FEEDMATRIX_ENTRY(S,  8, NE),
218 	FEEDMATRIX_ENTRY(S, 24, LE),
219 	FEEDMATRIX_ENTRY(S, 24, BE),
220 	FEEDMATRIX_ENTRY(U,  8, NE),
221 	FEEDMATRIX_ENTRY(U, 16, LE),
222 	FEEDMATRIX_ENTRY(U, 24, LE),
223 	FEEDMATRIX_ENTRY(U, 32, LE),
224 	FEEDMATRIX_ENTRY(U, 16, BE),
225 	FEEDMATRIX_ENTRY(U, 24, BE),
226 	FEEDMATRIX_ENTRY(U, 32, BE)
227 #endif
228 };
229 
230 static void
231 feed_matrix_reset(struct feed_matrix_info *info)
232 {
233 	uint32_t i, j;
234 
235 	for (i = 0; i < (sizeof(info->matrix) / sizeof(info->matrix[0])); i++) {
236 		for (j = 0;
237 		    j < (sizeof(info->matrix[i].chn) /
238 		    sizeof(info->matrix[i].chn[0])); j++) {
239 			info->matrix[i].chn[j] = SND_CHN_T_EOF;
240 		}
241 		info->matrix[i].mul   = 1;
242 		info->matrix[i].shift = 0;
243 	}
244 }
245 
246 #ifdef FEEDMATRIX_GENERIC
247 static void
248 feed_matrix_apply_generic(struct feed_matrix_info *info,
249     uint8_t *src, uint8_t *dst, uint32_t count)
250 {
251 	intpcm64_t accum;
252 	intpcm_t v;
253 	int i, j;
254 
255 	do {
256 		for (i = 0; info->matrix[i].chn[0] != SND_CHN_T_EOF;
257 		    i++) {
258 			if (info->matrix[i].chn[0] == SND_CHN_T_NULL) {
259 				info->wr(dst, 0);
260 				dst += info->bps;
261 				continue;
262 			} else if (info->matrix[i].chn[1] ==
263 			    SND_CHN_T_EOF) {
264 				v = info->rd(src + info->matrix[i].chn[0]);
265 				info->wr(dst, v);
266 				dst += info->bps;
267 				continue;
268 			}
269 
270 			accum = 0;
271 			for (j = 0;
272 			    info->matrix[i].chn[j] != SND_CHN_T_EOF;
273 			    j++) {
274 				v = info->rd(src + info->matrix[i].chn[j]);
275 				accum += v;
276 			}
277 
278 			accum = (accum * info->matrix[i].mul) >>
279 			    info->matrix[i].shift;
280 
281 			FEEDMATRIX_CLIP_CHECK(accum, 32);
282 
283 			v = (accum > PCM_S32_MAX) ? PCM_S32_MAX :
284 			    ((accum < PCM_S32_MIN) ? PCM_S32_MIN : accum);
285 			info->wr(dst, v);
286 			dst += info->bps;
287 		}
288 		src += info->ialign;
289 	} while (--count != 0);
290 }
291 #endif
292 
293 static int
294 feed_matrix_setup(struct feed_matrix_info *info, struct pcmchan_matrix *m_in,
295     struct pcmchan_matrix *m_out)
296 {
297 	uint32_t i, j, ch, in_mask, merge_mask;
298 	int mul, shift;
299 
300 	if (info == NULL || m_in == NULL || m_out == NULL ||
301 	    AFMT_CHANNEL(info->in) != m_in->channels ||
302 	    AFMT_CHANNEL(info->out) != m_out->channels ||
303 	    m_in->channels < SND_CHN_MIN || m_in->channels > SND_CHN_MAX ||
304 	    m_out->channels < SND_CHN_MIN || m_out->channels > SND_CHN_MAX)
305 		return (EINVAL);
306 
307 	feed_matrix_reset(info);
308 
309 	/*
310 	 * If both in and out are part of standard matrix and identical, skip
311 	 * everything alltogether.
312 	 */
313 	if (m_in->id == m_out->id && !(m_in->id < SND_CHN_MATRIX_BEGIN ||
314 	    m_in->id > SND_CHN_MATRIX_END))
315 		return (0);
316 
317 	/*
318 	 * Special case for mono input matrix. If the output supports
319 	 * possible 'center' channel, route it there. Otherwise, let it be
320 	 * matrixed to left/right.
321 	 */
322 	if (m_in->id == SND_CHN_MATRIX_1_0) {
323 		if (m_out->id == SND_CHN_MATRIX_1_0)
324 			in_mask = SND_CHN_T_MASK_FL;
325 		else if (m_out->mask & SND_CHN_T_MASK_FC)
326 			in_mask = SND_CHN_T_MASK_FC;
327 		else
328 			in_mask = SND_CHN_T_MASK_FL | SND_CHN_T_MASK_FR;
329 	} else
330 		in_mask = m_in->mask;
331 
332 	/* Merge, reduce, expand all possibilites. */
333 	for (ch = SND_CHN_T_BEGIN; ch <= SND_CHN_T_END &&
334 	    m_out->map[ch].type != SND_CHN_T_MAX; ch += SND_CHN_T_STEP) {
335 		merge_mask = m_out->map[ch].members & in_mask;
336 		if (merge_mask == 0) {
337 			info->matrix[ch].chn[0] = SND_CHN_T_NULL;
338 			continue;
339 		}
340 
341 		j = 0;
342 		for (i = SND_CHN_T_BEGIN; i <= SND_CHN_T_END;
343 		    i += SND_CHN_T_STEP) {
344 			if (merge_mask & (1 << i)) {
345 				if (m_in->offset[i] >= 0 &&
346 				    m_in->offset[i] < (int)m_in->channels)
347 					info->matrix[ch].chn[j++] =
348 					    m_in->offset[i] * info->bps;
349 				else {
350 					info->matrix[ch].chn[j++] =
351 					    SND_CHN_T_EOF;
352 					break;
353 				}
354 			}
355 		}
356 
357 #define FEEDMATRIX_ATTN_SHIFT	16
358 
359 		if (j > 1) {
360 			/*
361 			 * XXX For channel that require accumulation from
362 			 * multiple channels, apply a slight attenuation to
363 			 * avoid clipping.
364 			 */
365 			mul   = (1 << (FEEDMATRIX_ATTN_SHIFT - 1)) + 143 - j;
366 			shift = FEEDMATRIX_ATTN_SHIFT;
367 			while ((mul & 1) == 0 && shift > 0) {
368 				mul >>= 1;
369 				shift--;
370 			}
371 			info->matrix[ch].mul   = mul;
372 			info->matrix[ch].shift = shift;
373 		}
374 	}
375 
376 #ifndef _KERNEL
377 	fprintf(stderr, "Total: %d\n", ch);
378 
379 	for (i = 0; info->matrix[i].chn[0] != SND_CHN_T_EOF; i++) {
380 		fprintf(stderr, "%d: [", i);
381 		for (j = 0; info->matrix[i].chn[j] != SND_CHN_T_EOF; j++) {
382 			if (j != 0)
383 				fprintf(stderr, ", ");
384 			fprintf(stderr, "%d",
385 			    (info->matrix[i].chn[j] == SND_CHN_T_NULL) ?
386 			    0xffffffff : info->matrix[i].chn[j] / info->bps);
387 		}
388 		fprintf(stderr, "] attn: (x * %d) >> %d\n",
389 		    info->matrix[i].mul, info->matrix[i].shift);
390 	}
391 #endif
392 
393 	return (0);
394 }
395 
396 static int
397 feed_matrix_init(struct pcm_feeder *f)
398 {
399 	struct feed_matrix_info *info;
400 	struct pcmchan_matrix *m_in, *m_out;
401 	uint32_t i;
402 	int ret;
403 
404 	if (AFMT_ENCODING(f->desc->in) != AFMT_ENCODING(f->desc->out))
405 		return (EINVAL);
406 
407 	info = malloc(sizeof(*info), M_DEVBUF, M_NOWAIT | M_ZERO);
408 	if (info == NULL)
409 		return (ENOMEM);
410 
411 	info->in = f->desc->in;
412 	info->out = f->desc->out;
413 	info->bps = AFMT_BPS(info->in);
414 	info->ialign = AFMT_ALIGN(info->in);
415 	info->oalign = AFMT_ALIGN(info->out);
416 	info->apply = NULL;
417 
418 	for (i = 0; info->apply == NULL &&
419 	    i < (sizeof(feed_matrix_tab) / sizeof(feed_matrix_tab[0])); i++) {
420 		if (AFMT_ENCODING(info->in) == feed_matrix_tab[i].format)
421 			info->apply = feed_matrix_tab[i].apply;
422 	}
423 
424 	if (info->apply == NULL) {
425 #ifdef FEEDMATRIX_GENERIC
426 		info->rd = feeder_format_read_op(info->in);
427 		info->wr = feeder_format_write_op(info->out);
428 		if (info->rd == NULL || info->wr == NULL) {
429 			free(info, M_DEVBUF);
430 			return (EINVAL);
431 		}
432 		info->apply = feed_matrix_apply_generic;
433 #else
434 		free(info, M_DEVBUF);
435 		return (EINVAL);
436 #endif
437 	}
438 
439 	m_in  = feeder_matrix_format_map(info->in);
440 	m_out = feeder_matrix_format_map(info->out);
441 
442 	ret = feed_matrix_setup(info, m_in, m_out);
443 	if (ret != 0) {
444 		free(info, M_DEVBUF);
445 		return (ret);
446 	}
447 
448 	f->data = info;
449 
450 	return (0);
451 }
452 
453 static int
454 feed_matrix_free(struct pcm_feeder *f)
455 {
456 	struct feed_matrix_info *info;
457 
458 	info = f->data;
459 	if (info != NULL)
460 		free(info, M_DEVBUF);
461 
462 	f->data = NULL;
463 
464 	return (0);
465 }
466 
467 static int
468 feed_matrix_feed(struct pcm_feeder *f, struct pcm_channel *c, uint8_t *b,
469     uint32_t count, void *source)
470 {
471 	struct feed_matrix_info *info;
472 	uint32_t j, inmax;
473 	uint8_t *src, *dst;
474 
475 	info = f->data;
476 	if (info->matrix[0].chn[0] == SND_CHN_T_EOF)
477 		return (FEEDER_FEED(f->source, c, b, count, source));
478 
479 	dst = b;
480 	count = SND_FXROUND(count, info->oalign);
481 	inmax = info->ialign + info->oalign;
482 
483 	/*
484 	 * This loop might look simmilar to other feeder_* loops, but be
485 	 * advised: matrixing might involve overlapping (think about
486 	 * swapping end to front or something like that). In this regard it
487 	 * might be simmilar to feeder_format, but feeder_format works on
488 	 * 'sample' domain where it can be fitted into single 32bit integer
489 	 * while matrixing works on 'sample frame' domain.
490 	 */
491 	do {
492 		if (count < info->oalign)
493 			break;
494 
495 		if (count < inmax) {
496 			src = info->reservoir;
497 			j = info->ialign;
498 		} else {
499 			if (info->ialign == info->oalign)
500 				j = count - info->oalign;
501 			else if (info->ialign > info->oalign)
502 				j = SND_FXROUND(count - info->oalign,
503 				    info->ialign);
504 			else
505 				j = (SND_FXDIV(count, info->oalign) - 1) *
506 				    info->ialign;
507 			src = dst + count - j;
508 		}
509 
510 		j = SND_FXDIV(FEEDER_FEED(f->source, c, src, j, source),
511 		    info->ialign);
512 		if (j == 0)
513 			break;
514 
515 		info->apply(info, src, dst, j);
516 
517 		j *= info->oalign;
518 		dst += j;
519 		count -= j;
520 
521 	} while (count != 0);
522 
523 	return (dst - b);
524 }
525 
526 static struct pcm_feederdesc feeder_matrix_desc[] = {
527 	{ FEEDER_MATRIX, 0, 0, 0, 0 },
528 	{ 0, 0, 0, 0, 0 }
529 };
530 
531 static kobj_method_t feeder_matrix_methods[] = {
532 	KOBJMETHOD(feeder_init,		feed_matrix_init),
533 	KOBJMETHOD(feeder_free,		feed_matrix_free),
534 	KOBJMETHOD(feeder_feed,		feed_matrix_feed),
535 	KOBJMETHOD_END
536 };
537 
538 FEEDER_DECLARE(feeder_matrix, NULL);
539 
540 /* External */
541 int
542 feeder_matrix_setup(struct pcm_feeder *f, struct pcmchan_matrix *m_in,
543     struct pcmchan_matrix *m_out)
544 {
545 
546 	if (f == NULL || f->desc == NULL || f->desc->type != FEEDER_MATRIX ||
547 	    f->data == NULL)
548 		return (EINVAL);
549 
550 	return (feed_matrix_setup(f->data, m_in, m_out));
551 }
552 
553 /*
554  * feeder_matrix_default_id(): For a given number of channels, return
555  *                             default preferred id (example: both 5.1 and
556  *                             6.0 are simply 6 channels, but 5.1 is more
557  *                             preferable).
558  */
559 int
560 feeder_matrix_default_id(uint32_t ch)
561 {
562 
563 	if (ch < feeder_matrix_maps[SND_CHN_MATRIX_BEGIN].channels ||
564 	    ch > feeder_matrix_maps[SND_CHN_MATRIX_END].channels)
565 		return (SND_CHN_MATRIX_UNKNOWN);
566 
567 	return (feeder_matrix_maps[feeder_matrix_default_ids[ch]].id);
568 }
569 
570 /*
571  * feeder_matrix_default_channel_map(): Ditto, but return matrix map
572  *                                      instead.
573  */
574 struct pcmchan_matrix *
575 feeder_matrix_default_channel_map(uint32_t ch)
576 {
577 
578 	if (ch < feeder_matrix_maps[SND_CHN_MATRIX_BEGIN].channels ||
579 	    ch > feeder_matrix_maps[SND_CHN_MATRIX_END].channels)
580 		return (NULL);
581 
582 	return (&feeder_matrix_maps[feeder_matrix_default_ids[ch]]);
583 }
584 
585 /*
586  * feeder_matrix_default_format(): For a given audio format, return the
587  *                                 proper audio format based on preferable
588  *                                 matrix.
589  */
590 uint32_t
591 feeder_matrix_default_format(uint32_t format)
592 {
593 	struct pcmchan_matrix *m;
594 	uint32_t i, ch, ext;
595 
596 	ch = AFMT_CHANNEL(format);
597 	ext = AFMT_EXTCHANNEL(format);
598 
599 	if (ext != 0) {
600 		for (i = SND_CHN_MATRIX_BEGIN; i <= SND_CHN_MATRIX_END; i++) {
601 			if (feeder_matrix_maps[i].channels == ch &&
602 			    feeder_matrix_maps[i].ext == ext)
603 			return (SND_FORMAT(format, ch, ext));
604 		}
605 	}
606 
607 	m = feeder_matrix_default_channel_map(ch);
608 	if (m == NULL)
609 		return (0x00000000);
610 
611 	return (SND_FORMAT(format, ch, m->ext));
612 }
613 
614 /*
615  * feeder_matrix_format_id(): For a given audio format, return its matrix
616  *                            id.
617  */
618 int
619 feeder_matrix_format_id(uint32_t format)
620 {
621 	uint32_t i, ch, ext;
622 
623 	ch = AFMT_CHANNEL(format);
624 	ext = AFMT_EXTCHANNEL(format);
625 
626 	for (i = SND_CHN_MATRIX_BEGIN; i <= SND_CHN_MATRIX_END; i++) {
627 		if (feeder_matrix_maps[i].channels == ch &&
628 		    feeder_matrix_maps[i].ext == ext)
629 			return (feeder_matrix_maps[i].id);
630 	}
631 
632 	return (SND_CHN_MATRIX_UNKNOWN);
633 }
634 
635 /*
636  * feeder_matrix_format_map(): For a given audio format, return its matrix
637  *                             map.
638  */
639 struct pcmchan_matrix *
640 feeder_matrix_format_map(uint32_t format)
641 {
642 	uint32_t i, ch, ext;
643 
644 	ch = AFMT_CHANNEL(format);
645 	ext = AFMT_EXTCHANNEL(format);
646 
647 	for (i = SND_CHN_MATRIX_BEGIN; i <= SND_CHN_MATRIX_END; i++) {
648 		if (feeder_matrix_maps[i].channels == ch &&
649 		    feeder_matrix_maps[i].ext == ext)
650 			return (&feeder_matrix_maps[i]);
651 	}
652 
653 	return (NULL);
654 }
655 
656 /*
657  * feeder_matrix_id_map(): For a given matrix id, return its matrix map.
658  */
659 struct pcmchan_matrix *
660 feeder_matrix_id_map(int id)
661 {
662 
663 	if (id < SND_CHN_MATRIX_BEGIN || id > SND_CHN_MATRIX_END)
664 		return (NULL);
665 
666 	return (&feeder_matrix_maps[id]);
667 }
668 
669 /*
670  * feeder_matrix_compare(): Compare the simmilarities of matrices.
671  */
672 int
673 feeder_matrix_compare(struct pcmchan_matrix *m_in, struct pcmchan_matrix *m_out)
674 {
675 	uint32_t i;
676 
677 	if (m_in == m_out)
678 		return (0);
679 
680 	if (m_in->channels != m_out->channels || m_in->ext != m_out->ext ||
681 	    m_in->mask != m_out->mask)
682 		return (1);
683 
684 	for (i = 0; i < (sizeof(m_in->map) / sizeof(m_in->map[0])); i++) {
685 		if (m_in->map[i].type != m_out->map[i].type)
686 			return (1);
687 		if (m_in->map[i].type == SND_CHN_T_MAX)
688 			break;
689 		if (m_in->map[i].members != m_out->map[i].members)
690 			return (1);
691 		if (i <= SND_CHN_T_END) {
692 			if (m_in->offset[m_in->map[i].type] !=
693 			    m_out->offset[m_out->map[i].type])
694 				return (1);
695 		}
696 	}
697 
698 	return (0);
699 }
700 
701 /*
702  * XXX 4front interpretation of "surround" is ambigous and sort of
703  *     conflicting with "rear"/"back". Map it to "side". Well..
704  *     who cares?
705  */
706 static int snd_chn_to_oss[SND_CHN_T_MAX] = {
707 	[SND_CHN_T_FL] = CHID_L,
708 	[SND_CHN_T_FR] = CHID_R,
709 	[SND_CHN_T_FC] = CHID_C,
710 	[SND_CHN_T_LF] = CHID_LFE,
711 	[SND_CHN_T_SL] = CHID_LS,
712 	[SND_CHN_T_SR] = CHID_RS,
713 	[SND_CHN_T_BL] = CHID_LR,
714 	[SND_CHN_T_BR] = CHID_RR
715 };
716 
717 #define SND_CHN_OSS_VALIDMASK						\
718 			(SND_CHN_T_MASK_FL | SND_CHN_T_MASK_FR |	\
719 			 SND_CHN_T_MASK_FC | SND_CHN_T_MASK_LF |	\
720 			 SND_CHN_T_MASK_SL | SND_CHN_T_MASK_SR |	\
721 			 SND_CHN_T_MASK_BL | SND_CHN_T_MASK_BR)
722 
723 #define SND_CHN_OSS_MAX		8
724 #define SND_CHN_OSS_BEGIN	CHID_L
725 #define SND_CHN_OSS_END		CHID_RR
726 
727 static int oss_to_snd_chn[SND_CHN_OSS_END + 1] = {
728 	[CHID_L]   = SND_CHN_T_FL,
729 	[CHID_R]   = SND_CHN_T_FR,
730 	[CHID_C]   = SND_CHN_T_FC,
731 	[CHID_LFE] = SND_CHN_T_LF,
732 	[CHID_LS]  = SND_CHN_T_SL,
733 	[CHID_RS]  = SND_CHN_T_SR,
734 	[CHID_LR]  = SND_CHN_T_BL,
735 	[CHID_RR]  = SND_CHN_T_BR
736 };
737 
738 /*
739  * Used by SNDCTL_DSP_GET_CHNORDER.
740  */
741 int
742 feeder_matrix_oss_get_channel_order(struct pcmchan_matrix *m,
743     unsigned long long *map)
744 {
745 	unsigned long long tmpmap;
746 	uint32_t i;
747 
748 	if (m == NULL || map == NULL || (m->mask & ~SND_CHN_OSS_VALIDMASK) ||
749 	    m->channels > SND_CHN_OSS_MAX)
750 		return (EINVAL);
751 
752 	tmpmap = 0x0000000000000000ULL;
753 
754 	for (i = 0; i < SND_CHN_OSS_MAX && m->map[i].type != SND_CHN_T_MAX;
755 	    i++) {
756 		if ((1 << m->map[i].type) & ~SND_CHN_OSS_VALIDMASK)
757 			return (EINVAL);
758 		tmpmap |=
759 		    (unsigned long long)snd_chn_to_oss[m->map[i].type] <<
760 		    (i * 4);
761 	}
762 
763 	*map = tmpmap;
764 
765 	return (0);
766 }
767 
768 /*
769  * Used by SNDCTL_DSP_SET_CHNORDER.
770  */
771 int
772 feeder_matrix_oss_set_channel_order(struct pcmchan_matrix *m,
773     unsigned long long *map)
774 {
775 	struct pcmchan_matrix tmp;
776 	uint32_t chmask, i;
777 	int ch, cheof;
778 
779 	if (m == NULL || map == NULL || (m->mask & ~SND_CHN_OSS_VALIDMASK) ||
780 	    m->channels > SND_CHN_OSS_MAX || (*map & 0xffffffff00000000ULL))
781 		return (EINVAL);
782 
783 	tmp = *m;
784 	tmp.channels = 0;
785 	tmp.ext = 0;
786 	tmp.mask = 0;
787 	memset(tmp.offset, -1, sizeof(tmp.offset));
788 	cheof = 0;
789 
790 	for (i = 0; i < SND_CHN_OSS_MAX; i++) {
791 		ch = (*map >> (i * 4)) & 0xf;
792 		if (ch < SND_CHN_OSS_BEGIN) {
793 			if (cheof == 0 && m->map[i].type != SND_CHN_T_MAX)
794 				return (EINVAL);
795 			cheof++;
796 			tmp.map[i] = m->map[i];
797 			continue;
798 		} else if (ch > SND_CHN_OSS_END)
799 			return (EINVAL);
800 		else if (cheof != 0)
801 			return (EINVAL);
802 		ch = oss_to_snd_chn[ch];
803 		chmask = 1 << ch;
804 		/* channel not exist in matrix */
805 		if (!(chmask & m->mask))
806 			return (EINVAL);
807 		/* duplicated channel */
808 		if (chmask & tmp.mask)
809 			return (EINVAL);
810 		tmp.map[i] = m->map[m->offset[ch]];
811 		if (tmp.map[i].type != ch)
812 			return (EINVAL);
813 		tmp.offset[ch] = i;
814 		tmp.mask |= chmask;
815 		tmp.channels++;
816 		if (chmask & SND_CHN_T_MASK_LF)
817 			tmp.ext++;
818 	}
819 
820 	if (tmp.channels != m->channels || tmp.ext != m->ext ||
821 	    tmp.mask != m->mask ||
822 	    tmp.map[m->channels].type != SND_CHN_T_MAX)
823 		return (EINVAL);
824 
825 	*m = tmp;
826 
827 	return (0);
828 }
829