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v5.4
  1/*
  2 *  PCM Interface - misc routines
  3 *  Copyright (c) 1998 by Jaroslav Kysela <perex@perex.cz>
  4 *
  5 *
  6 *   This library is free software; you can redistribute it and/or modify
  7 *   it under the terms of the GNU Library General Public License as
  8 *   published by the Free Software Foundation; either version 2 of
  9 *   the License, or (at your option) any later version.
 10 *
 11 *   This program is distributed in the hope that it will be useful,
 12 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 *   GNU Library General Public License for more details.
 15 *
 16 *   You should have received a copy of the GNU Library General Public
 17 *   License along with this library; if not, write to the Free Software
 18 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 19 *
 20 */
 21  
 22#include <linux/time.h>
 23#include <linux/export.h>
 24#include <sound/core.h>
 25#include <sound/pcm.h>
 26
 27#include "pcm_local.h"
 28
 29#define SND_PCM_FORMAT_UNKNOWN (-1)
 30
 31/* NOTE: "signed" prefix must be given below since the default char is
 32 *       unsigned on some architectures!
 33 */
 34struct pcm_format_data {
 35	unsigned char width;	/* bit width */
 36	unsigned char phys;	/* physical bit width */
 37	signed char le;	/* 0 = big-endian, 1 = little-endian, -1 = others */
 38	signed char signd;	/* 0 = unsigned, 1 = signed, -1 = others */
 39	unsigned char silence[8];	/* silence data to fill */
 40};
 41
 42/* we do lots of calculations on snd_pcm_format_t; shut up sparse */
 43#define INT	__force int
 44
 45static struct pcm_format_data pcm_formats[(INT)SNDRV_PCM_FORMAT_LAST+1] = {
 46	[SNDRV_PCM_FORMAT_S8] = {
 47		.width = 8, .phys = 8, .le = -1, .signd = 1,
 48		.silence = {},
 49	},
 50	[SNDRV_PCM_FORMAT_U8] = {
 51		.width = 8, .phys = 8, .le = -1, .signd = 0,
 52		.silence = { 0x80 },
 53	},
 54	[SNDRV_PCM_FORMAT_S16_LE] = {
 55		.width = 16, .phys = 16, .le = 1, .signd = 1,
 56		.silence = {},
 57	},
 58	[SNDRV_PCM_FORMAT_S16_BE] = {
 59		.width = 16, .phys = 16, .le = 0, .signd = 1,
 60		.silence = {},
 61	},
 62	[SNDRV_PCM_FORMAT_U16_LE] = {
 63		.width = 16, .phys = 16, .le = 1, .signd = 0,
 64		.silence = { 0x00, 0x80 },
 65	},
 66	[SNDRV_PCM_FORMAT_U16_BE] = {
 67		.width = 16, .phys = 16, .le = 0, .signd = 0,
 68		.silence = { 0x80, 0x00 },
 69	},
 70	[SNDRV_PCM_FORMAT_S24_LE] = {
 71		.width = 24, .phys = 32, .le = 1, .signd = 1,
 72		.silence = {},
 73	},
 74	[SNDRV_PCM_FORMAT_S24_BE] = {
 75		.width = 24, .phys = 32, .le = 0, .signd = 1,
 76		.silence = {},
 77	},
 78	[SNDRV_PCM_FORMAT_U24_LE] = {
 79		.width = 24, .phys = 32, .le = 1, .signd = 0,
 80		.silence = { 0x00, 0x00, 0x80 },
 81	},
 82	[SNDRV_PCM_FORMAT_U24_BE] = {
 83		.width = 24, .phys = 32, .le = 0, .signd = 0,
 84		.silence = { 0x00, 0x80, 0x00, 0x00 },
 85	},
 86	[SNDRV_PCM_FORMAT_S32_LE] = {
 87		.width = 32, .phys = 32, .le = 1, .signd = 1,
 88		.silence = {},
 89	},
 90	[SNDRV_PCM_FORMAT_S32_BE] = {
 91		.width = 32, .phys = 32, .le = 0, .signd = 1,
 92		.silence = {},
 93	},
 94	[SNDRV_PCM_FORMAT_U32_LE] = {
 95		.width = 32, .phys = 32, .le = 1, .signd = 0,
 96		.silence = { 0x00, 0x00, 0x00, 0x80 },
 97	},
 98	[SNDRV_PCM_FORMAT_U32_BE] = {
 99		.width = 32, .phys = 32, .le = 0, .signd = 0,
100		.silence = { 0x80, 0x00, 0x00, 0x00 },
101	},
102	[SNDRV_PCM_FORMAT_FLOAT_LE] = {
103		.width = 32, .phys = 32, .le = 1, .signd = -1,
104		.silence = {},
105	},
106	[SNDRV_PCM_FORMAT_FLOAT_BE] = {
107		.width = 32, .phys = 32, .le = 0, .signd = -1,
108		.silence = {},
109	},
110	[SNDRV_PCM_FORMAT_FLOAT64_LE] = {
111		.width = 64, .phys = 64, .le = 1, .signd = -1,
112		.silence = {},
113	},
114	[SNDRV_PCM_FORMAT_FLOAT64_BE] = {
115		.width = 64, .phys = 64, .le = 0, .signd = -1,
116		.silence = {},
117	},
118	[SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE] = {
119		.width = 32, .phys = 32, .le = 1, .signd = -1,
120		.silence = {},
121	},
122	[SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE] = {
123		.width = 32, .phys = 32, .le = 0, .signd = -1,
124		.silence = {},
125	},
126	[SNDRV_PCM_FORMAT_MU_LAW] = {
127		.width = 8, .phys = 8, .le = -1, .signd = -1,
128		.silence = { 0x7f },
129	},
130	[SNDRV_PCM_FORMAT_A_LAW] = {
131		.width = 8, .phys = 8, .le = -1, .signd = -1,
132		.silence = { 0x55 },
133	},
134	[SNDRV_PCM_FORMAT_IMA_ADPCM] = {
135		.width = 4, .phys = 4, .le = -1, .signd = -1,
136		.silence = {},
137	},
138	[SNDRV_PCM_FORMAT_G723_24] = {
139		.width = 3, .phys = 3, .le = -1, .signd = -1,
140		.silence = {},
141	},
142	[SNDRV_PCM_FORMAT_G723_40] = {
143		.width = 5, .phys = 5, .le = -1, .signd = -1,
144		.silence = {},
145	},
146	[SNDRV_PCM_FORMAT_DSD_U8] = {
147		.width = 8, .phys = 8, .le = 1, .signd = 0,
148		.silence = { 0x69 },
149	},
150	[SNDRV_PCM_FORMAT_DSD_U16_LE] = {
151		.width = 16, .phys = 16, .le = 1, .signd = 0,
152		.silence = { 0x69, 0x69 },
153	},
154	[SNDRV_PCM_FORMAT_DSD_U32_LE] = {
155		.width = 32, .phys = 32, .le = 1, .signd = 0,
156		.silence = { 0x69, 0x69, 0x69, 0x69 },
157	},
158	[SNDRV_PCM_FORMAT_DSD_U16_BE] = {
159		.width = 16, .phys = 16, .le = 0, .signd = 0,
160		.silence = { 0x69, 0x69 },
161	},
162	[SNDRV_PCM_FORMAT_DSD_U32_BE] = {
163		.width = 32, .phys = 32, .le = 0, .signd = 0,
164		.silence = { 0x69, 0x69, 0x69, 0x69 },
165	},
166	/* FIXME: the following two formats are not defined properly yet */
167	[SNDRV_PCM_FORMAT_MPEG] = {
168		.le = -1, .signd = -1,
169	},
170	[SNDRV_PCM_FORMAT_GSM] = {
171		.le = -1, .signd = -1,
172	},
173	[SNDRV_PCM_FORMAT_S20_LE] = {
174		.width = 20, .phys = 32, .le = 1, .signd = 1,
175		.silence = {},
176	},
177	[SNDRV_PCM_FORMAT_S20_BE] = {
178		.width = 20, .phys = 32, .le = 0, .signd = 1,
179		.silence = {},
180	},
181	[SNDRV_PCM_FORMAT_U20_LE] = {
182		.width = 20, .phys = 32, .le = 1, .signd = 0,
183		.silence = { 0x00, 0x00, 0x08, 0x00 },
184	},
185	[SNDRV_PCM_FORMAT_U20_BE] = {
186		.width = 20, .phys = 32, .le = 0, .signd = 0,
187		.silence = { 0x00, 0x08, 0x00, 0x00 },
188	},
189	/* FIXME: the following format is not defined properly yet */
190	[SNDRV_PCM_FORMAT_SPECIAL] = {
191		.le = -1, .signd = -1,
192	},
193	[SNDRV_PCM_FORMAT_S24_3LE] = {
194		.width = 24, .phys = 24, .le = 1, .signd = 1,
195		.silence = {},
196	},
197	[SNDRV_PCM_FORMAT_S24_3BE] = {
198		.width = 24, .phys = 24, .le = 0, .signd = 1,
199		.silence = {},
200	},
201	[SNDRV_PCM_FORMAT_U24_3LE] = {
202		.width = 24, .phys = 24, .le = 1, .signd = 0,
203		.silence = { 0x00, 0x00, 0x80 },
204	},
205	[SNDRV_PCM_FORMAT_U24_3BE] = {
206		.width = 24, .phys = 24, .le = 0, .signd = 0,
207		.silence = { 0x80, 0x00, 0x00 },
208	},
209	[SNDRV_PCM_FORMAT_S20_3LE] = {
210		.width = 20, .phys = 24, .le = 1, .signd = 1,
211		.silence = {},
212	},
213	[SNDRV_PCM_FORMAT_S20_3BE] = {
214		.width = 20, .phys = 24, .le = 0, .signd = 1,
215		.silence = {},
216	},
217	[SNDRV_PCM_FORMAT_U20_3LE] = {
218		.width = 20, .phys = 24, .le = 1, .signd = 0,
219		.silence = { 0x00, 0x00, 0x08 },
220	},
221	[SNDRV_PCM_FORMAT_U20_3BE] = {
222		.width = 20, .phys = 24, .le = 0, .signd = 0,
223		.silence = { 0x08, 0x00, 0x00 },
224	},
225	[SNDRV_PCM_FORMAT_S18_3LE] = {
226		.width = 18, .phys = 24, .le = 1, .signd = 1,
227		.silence = {},
228	},
229	[SNDRV_PCM_FORMAT_S18_3BE] = {
230		.width = 18, .phys = 24, .le = 0, .signd = 1,
231		.silence = {},
232	},
233	[SNDRV_PCM_FORMAT_U18_3LE] = {
234		.width = 18, .phys = 24, .le = 1, .signd = 0,
235		.silence = { 0x00, 0x00, 0x02 },
236	},
237	[SNDRV_PCM_FORMAT_U18_3BE] = {
238		.width = 18, .phys = 24, .le = 0, .signd = 0,
239		.silence = { 0x02, 0x00, 0x00 },
240	},
241	[SNDRV_PCM_FORMAT_G723_24_1B] = {
242		.width = 3, .phys = 8, .le = -1, .signd = -1,
243		.silence = {},
244	},
245	[SNDRV_PCM_FORMAT_G723_40_1B] = {
246		.width = 5, .phys = 8, .le = -1, .signd = -1,
247		.silence = {},
248	},
249};
250
251
252/**
253 * snd_pcm_format_signed - Check the PCM format is signed linear
254 * @format: the format to check
255 *
256 * Return: 1 if the given PCM format is signed linear, 0 if unsigned
257 * linear, and a negative error code for non-linear formats.
258 */
259int snd_pcm_format_signed(snd_pcm_format_t format)
260{
261	int val;
262	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
263		return -EINVAL;
264	if ((val = pcm_formats[(INT)format].signd) < 0)
265		return -EINVAL;
266	return val;
267}
 
268EXPORT_SYMBOL(snd_pcm_format_signed);
269
270/**
271 * snd_pcm_format_unsigned - Check the PCM format is unsigned linear
272 * @format: the format to check
273 *
274 * Return: 1 if the given PCM format is unsigned linear, 0 if signed
275 * linear, and a negative error code for non-linear formats.
276 */
277int snd_pcm_format_unsigned(snd_pcm_format_t format)
278{
279	int val;
280
281	val = snd_pcm_format_signed(format);
282	if (val < 0)
283		return val;
284	return !val;
285}
 
286EXPORT_SYMBOL(snd_pcm_format_unsigned);
287
288/**
289 * snd_pcm_format_linear - Check the PCM format is linear
290 * @format: the format to check
291 *
292 * Return: 1 if the given PCM format is linear, 0 if not.
293 */
294int snd_pcm_format_linear(snd_pcm_format_t format)
295{
296	return snd_pcm_format_signed(format) >= 0;
297}
 
298EXPORT_SYMBOL(snd_pcm_format_linear);
299
300/**
301 * snd_pcm_format_little_endian - Check the PCM format is little-endian
302 * @format: the format to check
303 *
304 * Return: 1 if the given PCM format is little-endian, 0 if
305 * big-endian, or a negative error code if endian not specified.
306 */
307int snd_pcm_format_little_endian(snd_pcm_format_t format)
308{
309	int val;
310	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
311		return -EINVAL;
312	if ((val = pcm_formats[(INT)format].le) < 0)
313		return -EINVAL;
314	return val;
315}
 
316EXPORT_SYMBOL(snd_pcm_format_little_endian);
317
318/**
319 * snd_pcm_format_big_endian - Check the PCM format is big-endian
320 * @format: the format to check
321 *
322 * Return: 1 if the given PCM format is big-endian, 0 if
323 * little-endian, or a negative error code if endian not specified.
324 */
325int snd_pcm_format_big_endian(snd_pcm_format_t format)
326{
327	int val;
328
329	val = snd_pcm_format_little_endian(format);
330	if (val < 0)
331		return val;
332	return !val;
333}
 
334EXPORT_SYMBOL(snd_pcm_format_big_endian);
335
336/**
337 * snd_pcm_format_width - return the bit-width of the format
338 * @format: the format to check
339 *
340 * Return: The bit-width of the format, or a negative error code
341 * if unknown format.
342 */
343int snd_pcm_format_width(snd_pcm_format_t format)
344{
345	int val;
346	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
347		return -EINVAL;
348	if ((val = pcm_formats[(INT)format].width) == 0)
349		return -EINVAL;
350	return val;
351}
 
352EXPORT_SYMBOL(snd_pcm_format_width);
353
354/**
355 * snd_pcm_format_physical_width - return the physical bit-width of the format
356 * @format: the format to check
357 *
358 * Return: The physical bit-width of the format, or a negative error code
359 * if unknown format.
360 */
361int snd_pcm_format_physical_width(snd_pcm_format_t format)
362{
363	int val;
364	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
365		return -EINVAL;
366	if ((val = pcm_formats[(INT)format].phys) == 0)
367		return -EINVAL;
368	return val;
369}
 
370EXPORT_SYMBOL(snd_pcm_format_physical_width);
371
372/**
373 * snd_pcm_format_size - return the byte size of samples on the given format
374 * @format: the format to check
375 * @samples: sampling rate
376 *
377 * Return: The byte size of the given samples for the format, or a
378 * negative error code if unknown format.
379 */
380ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples)
381{
382	int phys_width = snd_pcm_format_physical_width(format);
383	if (phys_width < 0)
384		return -EINVAL;
385	return samples * phys_width / 8;
386}
 
387EXPORT_SYMBOL(snd_pcm_format_size);
388
389/**
390 * snd_pcm_format_silence_64 - return the silent data in 8 bytes array
391 * @format: the format to check
392 *
393 * Return: The format pattern to fill or %NULL if error.
394 */
395const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format)
396{
397	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
398		return NULL;
399	if (! pcm_formats[(INT)format].phys)
400		return NULL;
401	return pcm_formats[(INT)format].silence;
402}
 
403EXPORT_SYMBOL(snd_pcm_format_silence_64);
404
405/**
406 * snd_pcm_format_set_silence - set the silence data on the buffer
407 * @format: the PCM format
408 * @data: the buffer pointer
409 * @samples: the number of samples to set silence
410 *
411 * Sets the silence data on the buffer for the given samples.
412 *
413 * Return: Zero if successful, or a negative error code on failure.
414 */
415int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples)
416{
417	int width;
418	unsigned char *dst, *pat;
419
420	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
421		return -EINVAL;
422	if (samples == 0)
423		return 0;
424	width = pcm_formats[(INT)format].phys; /* physical width */
425	pat = pcm_formats[(INT)format].silence;
426	if (! width)
427		return -EINVAL;
428	/* signed or 1 byte data */
429	if (pcm_formats[(INT)format].signd == 1 || width <= 8) {
430		unsigned int bytes = samples * width / 8;
431		memset(data, *pat, bytes);
432		return 0;
433	}
434	/* non-zero samples, fill using a loop */
435	width /= 8;
436	dst = data;
437#if 0
438	while (samples--) {
439		memcpy(dst, pat, width);
440		dst += width;
441	}
442#else
443	/* a bit optimization for constant width */
444	switch (width) {
445	case 2:
446		while (samples--) {
447			memcpy(dst, pat, 2);
448			dst += 2;
449		}
450		break;
451	case 3:
452		while (samples--) {
453			memcpy(dst, pat, 3);
454			dst += 3;
455		}
456		break;
457	case 4:
458		while (samples--) {
459			memcpy(dst, pat, 4);
460			dst += 4;
461		}
462		break;
463	case 8:
464		while (samples--) {
465			memcpy(dst, pat, 8);
466			dst += 8;
467		}
468		break;
469	}
470#endif
471	return 0;
472}
 
473EXPORT_SYMBOL(snd_pcm_format_set_silence);
474
475/**
476 * snd_pcm_limit_hw_rates - determine rate_min/rate_max fields
477 * @runtime: the runtime instance
478 *
479 * Determines the rate_min and rate_max fields from the rates bits of
480 * the given runtime->hw.
481 *
482 * Return: Zero if successful.
483 */
484int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime)
485{
486	int i;
487	for (i = 0; i < (int)snd_pcm_known_rates.count; i++) {
488		if (runtime->hw.rates & (1 << i)) {
489			runtime->hw.rate_min = snd_pcm_known_rates.list[i];
490			break;
491		}
492	}
493	for (i = (int)snd_pcm_known_rates.count - 1; i >= 0; i--) {
494		if (runtime->hw.rates & (1 << i)) {
495			runtime->hw.rate_max = snd_pcm_known_rates.list[i];
496			break;
497		}
498	}
499	return 0;
500}
 
501EXPORT_SYMBOL(snd_pcm_limit_hw_rates);
502
503/**
504 * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit
505 * @rate: the sample rate to convert
506 *
507 * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or
508 * SNDRV_PCM_RATE_KNOT for an unknown rate.
509 */
510unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate)
511{
512	unsigned int i;
513
514	for (i = 0; i < snd_pcm_known_rates.count; i++)
515		if (snd_pcm_known_rates.list[i] == rate)
516			return 1u << i;
517	return SNDRV_PCM_RATE_KNOT;
518}
519EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit);
520
521/**
522 * snd_pcm_rate_bit_to_rate - converts SNDRV_PCM_RATE_xxx bit to sample rate
523 * @rate_bit: the rate bit to convert
524 *
525 * Return: The sample rate that corresponds to the given SNDRV_PCM_RATE_xxx flag
526 * or 0 for an unknown rate bit.
527 */
528unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit)
529{
530	unsigned int i;
531
532	for (i = 0; i < snd_pcm_known_rates.count; i++)
533		if ((1u << i) == rate_bit)
534			return snd_pcm_known_rates.list[i];
535	return 0;
536}
537EXPORT_SYMBOL(snd_pcm_rate_bit_to_rate);
538
539static unsigned int snd_pcm_rate_mask_sanitize(unsigned int rates)
540{
541	if (rates & SNDRV_PCM_RATE_CONTINUOUS)
542		return SNDRV_PCM_RATE_CONTINUOUS;
543	else if (rates & SNDRV_PCM_RATE_KNOT)
544		return SNDRV_PCM_RATE_KNOT;
545	return rates;
546}
547
548/**
549 * snd_pcm_rate_mask_intersect - computes the intersection between two rate masks
550 * @rates_a: The first rate mask
551 * @rates_b: The second rate mask
552 *
553 * This function computes the rates that are supported by both rate masks passed
554 * to the function. It will take care of the special handling of
555 * SNDRV_PCM_RATE_CONTINUOUS and SNDRV_PCM_RATE_KNOT.
556 *
557 * Return: A rate mask containing the rates that are supported by both rates_a
558 * and rates_b.
559 */
560unsigned int snd_pcm_rate_mask_intersect(unsigned int rates_a,
561	unsigned int rates_b)
562{
563	rates_a = snd_pcm_rate_mask_sanitize(rates_a);
564	rates_b = snd_pcm_rate_mask_sanitize(rates_b);
565
566	if (rates_a & SNDRV_PCM_RATE_CONTINUOUS)
567		return rates_b;
568	else if (rates_b & SNDRV_PCM_RATE_CONTINUOUS)
569		return rates_a;
570	else if (rates_a & SNDRV_PCM_RATE_KNOT)
571		return rates_b;
572	else if (rates_b & SNDRV_PCM_RATE_KNOT)
573		return rates_a;
574	return rates_a & rates_b;
575}
576EXPORT_SYMBOL_GPL(snd_pcm_rate_mask_intersect);
577
578/**
579 * snd_pcm_rate_range_to_bits - converts rate range to SNDRV_PCM_RATE_xxx bit
580 * @rate_min: the minimum sample rate
581 * @rate_max: the maximum sample rate
582 *
583 * This function has an implicit assumption: the rates in the given range have
584 * only the pre-defined rates like 44100 or 16000.
585 *
586 * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate range,
587 * or SNDRV_PCM_RATE_KNOT for an unknown range.
588 */
589unsigned int snd_pcm_rate_range_to_bits(unsigned int rate_min,
590	unsigned int rate_max)
591{
592	unsigned int rates = 0;
593	int i;
594
595	for (i = 0; i < snd_pcm_known_rates.count; i++) {
596		if (snd_pcm_known_rates.list[i] >= rate_min
597			&& snd_pcm_known_rates.list[i] <= rate_max)
598			rates |= 1 << i;
599	}
600
601	if (!rates)
602		rates = SNDRV_PCM_RATE_KNOT;
603
604	return rates;
605}
606EXPORT_SYMBOL_GPL(snd_pcm_rate_range_to_bits);
v3.1
  1/*
  2 *  PCM Interface - misc routines
  3 *  Copyright (c) 1998 by Jaroslav Kysela <perex@perex.cz>
  4 *
  5 *
  6 *   This library is free software; you can redistribute it and/or modify
  7 *   it under the terms of the GNU Library General Public License as
  8 *   published by the Free Software Foundation; either version 2 of
  9 *   the License, or (at your option) any later version.
 10 *
 11 *   This program is distributed in the hope that it will be useful,
 12 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 *   GNU Library General Public License for more details.
 15 *
 16 *   You should have received a copy of the GNU Library General Public
 17 *   License along with this library; if not, write to the Free Software
 18 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 19 *
 20 */
 21  
 22#include <linux/time.h>
 
 23#include <sound/core.h>
 24#include <sound/pcm.h>
 
 
 
 25#define SND_PCM_FORMAT_UNKNOWN (-1)
 26
 27/* NOTE: "signed" prefix must be given below since the default char is
 28 *       unsigned on some architectures!
 29 */
 30struct pcm_format_data {
 31	unsigned char width;	/* bit width */
 32	unsigned char phys;	/* physical bit width */
 33	signed char le;	/* 0 = big-endian, 1 = little-endian, -1 = others */
 34	signed char signd;	/* 0 = unsigned, 1 = signed, -1 = others */
 35	unsigned char silence[8];	/* silence data to fill */
 36};
 37
 38/* we do lots of calculations on snd_pcm_format_t; shut up sparse */
 39#define INT	__force int
 40
 41static struct pcm_format_data pcm_formats[(INT)SNDRV_PCM_FORMAT_LAST+1] = {
 42	[SNDRV_PCM_FORMAT_S8] = {
 43		.width = 8, .phys = 8, .le = -1, .signd = 1,
 44		.silence = {},
 45	},
 46	[SNDRV_PCM_FORMAT_U8] = {
 47		.width = 8, .phys = 8, .le = -1, .signd = 0,
 48		.silence = { 0x80 },
 49	},
 50	[SNDRV_PCM_FORMAT_S16_LE] = {
 51		.width = 16, .phys = 16, .le = 1, .signd = 1,
 52		.silence = {},
 53	},
 54	[SNDRV_PCM_FORMAT_S16_BE] = {
 55		.width = 16, .phys = 16, .le = 0, .signd = 1,
 56		.silence = {},
 57	},
 58	[SNDRV_PCM_FORMAT_U16_LE] = {
 59		.width = 16, .phys = 16, .le = 1, .signd = 0,
 60		.silence = { 0x00, 0x80 },
 61	},
 62	[SNDRV_PCM_FORMAT_U16_BE] = {
 63		.width = 16, .phys = 16, .le = 0, .signd = 0,
 64		.silence = { 0x80, 0x00 },
 65	},
 66	[SNDRV_PCM_FORMAT_S24_LE] = {
 67		.width = 24, .phys = 32, .le = 1, .signd = 1,
 68		.silence = {},
 69	},
 70	[SNDRV_PCM_FORMAT_S24_BE] = {
 71		.width = 24, .phys = 32, .le = 0, .signd = 1,
 72		.silence = {},
 73	},
 74	[SNDRV_PCM_FORMAT_U24_LE] = {
 75		.width = 24, .phys = 32, .le = 1, .signd = 0,
 76		.silence = { 0x00, 0x00, 0x80 },
 77	},
 78	[SNDRV_PCM_FORMAT_U24_BE] = {
 79		.width = 24, .phys = 32, .le = 0, .signd = 0,
 80		.silence = { 0x00, 0x80, 0x00, 0x00 },
 81	},
 82	[SNDRV_PCM_FORMAT_S32_LE] = {
 83		.width = 32, .phys = 32, .le = 1, .signd = 1,
 84		.silence = {},
 85	},
 86	[SNDRV_PCM_FORMAT_S32_BE] = {
 87		.width = 32, .phys = 32, .le = 0, .signd = 1,
 88		.silence = {},
 89	},
 90	[SNDRV_PCM_FORMAT_U32_LE] = {
 91		.width = 32, .phys = 32, .le = 1, .signd = 0,
 92		.silence = { 0x00, 0x00, 0x00, 0x80 },
 93	},
 94	[SNDRV_PCM_FORMAT_U32_BE] = {
 95		.width = 32, .phys = 32, .le = 0, .signd = 0,
 96		.silence = { 0x80, 0x00, 0x00, 0x00 },
 97	},
 98	[SNDRV_PCM_FORMAT_FLOAT_LE] = {
 99		.width = 32, .phys = 32, .le = 1, .signd = -1,
100		.silence = {},
101	},
102	[SNDRV_PCM_FORMAT_FLOAT_BE] = {
103		.width = 32, .phys = 32, .le = 0, .signd = -1,
104		.silence = {},
105	},
106	[SNDRV_PCM_FORMAT_FLOAT64_LE] = {
107		.width = 64, .phys = 64, .le = 1, .signd = -1,
108		.silence = {},
109	},
110	[SNDRV_PCM_FORMAT_FLOAT64_BE] = {
111		.width = 64, .phys = 64, .le = 0, .signd = -1,
112		.silence = {},
113	},
114	[SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE] = {
115		.width = 32, .phys = 32, .le = 1, .signd = -1,
116		.silence = {},
117	},
118	[SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE] = {
119		.width = 32, .phys = 32, .le = 0, .signd = -1,
120		.silence = {},
121	},
122	[SNDRV_PCM_FORMAT_MU_LAW] = {
123		.width = 8, .phys = 8, .le = -1, .signd = -1,
124		.silence = { 0x7f },
125	},
126	[SNDRV_PCM_FORMAT_A_LAW] = {
127		.width = 8, .phys = 8, .le = -1, .signd = -1,
128		.silence = { 0x55 },
129	},
130	[SNDRV_PCM_FORMAT_IMA_ADPCM] = {
131		.width = 4, .phys = 4, .le = -1, .signd = -1,
132		.silence = {},
133	},
134	[SNDRV_PCM_FORMAT_G723_24] = {
135		.width = 3, .phys = 3, .le = -1, .signd = -1,
136		.silence = {},
137	},
138	[SNDRV_PCM_FORMAT_G723_40] = {
139		.width = 5, .phys = 5, .le = -1, .signd = -1,
140		.silence = {},
141	},
142	/* FIXME: the following three formats are not defined properly yet */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
143	[SNDRV_PCM_FORMAT_MPEG] = {
144		.le = -1, .signd = -1,
145	},
146	[SNDRV_PCM_FORMAT_GSM] = {
147		.le = -1, .signd = -1,
148	},
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
149	[SNDRV_PCM_FORMAT_SPECIAL] = {
150		.le = -1, .signd = -1,
151	},
152	[SNDRV_PCM_FORMAT_S24_3LE] = {
153		.width = 24, .phys = 24, .le = 1, .signd = 1,
154		.silence = {},
155	},
156	[SNDRV_PCM_FORMAT_S24_3BE] = {
157		.width = 24, .phys = 24, .le = 0, .signd = 1,
158		.silence = {},
159	},
160	[SNDRV_PCM_FORMAT_U24_3LE] = {
161		.width = 24, .phys = 24, .le = 1, .signd = 0,
162		.silence = { 0x00, 0x00, 0x80 },
163	},
164	[SNDRV_PCM_FORMAT_U24_3BE] = {
165		.width = 24, .phys = 24, .le = 0, .signd = 0,
166		.silence = { 0x80, 0x00, 0x00 },
167	},
168	[SNDRV_PCM_FORMAT_S20_3LE] = {
169		.width = 20, .phys = 24, .le = 1, .signd = 1,
170		.silence = {},
171	},
172	[SNDRV_PCM_FORMAT_S20_3BE] = {
173		.width = 20, .phys = 24, .le = 0, .signd = 1,
174		.silence = {},
175	},
176	[SNDRV_PCM_FORMAT_U20_3LE] = {
177		.width = 20, .phys = 24, .le = 1, .signd = 0,
178		.silence = { 0x00, 0x00, 0x08 },
179	},
180	[SNDRV_PCM_FORMAT_U20_3BE] = {
181		.width = 20, .phys = 24, .le = 0, .signd = 0,
182		.silence = { 0x08, 0x00, 0x00 },
183	},
184	[SNDRV_PCM_FORMAT_S18_3LE] = {
185		.width = 18, .phys = 24, .le = 1, .signd = 1,
186		.silence = {},
187	},
188	[SNDRV_PCM_FORMAT_S18_3BE] = {
189		.width = 18, .phys = 24, .le = 0, .signd = 1,
190		.silence = {},
191	},
192	[SNDRV_PCM_FORMAT_U18_3LE] = {
193		.width = 18, .phys = 24, .le = 1, .signd = 0,
194		.silence = { 0x00, 0x00, 0x02 },
195	},
196	[SNDRV_PCM_FORMAT_U18_3BE] = {
197		.width = 18, .phys = 24, .le = 0, .signd = 0,
198		.silence = { 0x02, 0x00, 0x00 },
199	},
200	[SNDRV_PCM_FORMAT_G723_24_1B] = {
201		.width = 3, .phys = 8, .le = -1, .signd = -1,
202		.silence = {},
203	},
204	[SNDRV_PCM_FORMAT_G723_40_1B] = {
205		.width = 5, .phys = 8, .le = -1, .signd = -1,
206		.silence = {},
207	},
208};
209
210
211/**
212 * snd_pcm_format_signed - Check the PCM format is signed linear
213 * @format: the format to check
214 *
215 * Returns 1 if the given PCM format is signed linear, 0 if unsigned
216 * linear, and a negative error code for non-linear formats.
217 */
218int snd_pcm_format_signed(snd_pcm_format_t format)
219{
220	int val;
221	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
222		return -EINVAL;
223	if ((val = pcm_formats[(INT)format].signd) < 0)
224		return -EINVAL;
225	return val;
226}
227
228EXPORT_SYMBOL(snd_pcm_format_signed);
229
230/**
231 * snd_pcm_format_unsigned - Check the PCM format is unsigned linear
232 * @format: the format to check
233 *
234 * Returns 1 if the given PCM format is unsigned linear, 0 if signed
235 * linear, and a negative error code for non-linear formats.
236 */
237int snd_pcm_format_unsigned(snd_pcm_format_t format)
238{
239	int val;
240
241	val = snd_pcm_format_signed(format);
242	if (val < 0)
243		return val;
244	return !val;
245}
246
247EXPORT_SYMBOL(snd_pcm_format_unsigned);
248
249/**
250 * snd_pcm_format_linear - Check the PCM format is linear
251 * @format: the format to check
252 *
253 * Returns 1 if the given PCM format is linear, 0 if not.
254 */
255int snd_pcm_format_linear(snd_pcm_format_t format)
256{
257	return snd_pcm_format_signed(format) >= 0;
258}
259
260EXPORT_SYMBOL(snd_pcm_format_linear);
261
262/**
263 * snd_pcm_format_little_endian - Check the PCM format is little-endian
264 * @format: the format to check
265 *
266 * Returns 1 if the given PCM format is little-endian, 0 if
267 * big-endian, or a negative error code if endian not specified.
268 */
269int snd_pcm_format_little_endian(snd_pcm_format_t format)
270{
271	int val;
272	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
273		return -EINVAL;
274	if ((val = pcm_formats[(INT)format].le) < 0)
275		return -EINVAL;
276	return val;
277}
278
279EXPORT_SYMBOL(snd_pcm_format_little_endian);
280
281/**
282 * snd_pcm_format_big_endian - Check the PCM format is big-endian
283 * @format: the format to check
284 *
285 * Returns 1 if the given PCM format is big-endian, 0 if
286 * little-endian, or a negative error code if endian not specified.
287 */
288int snd_pcm_format_big_endian(snd_pcm_format_t format)
289{
290	int val;
291
292	val = snd_pcm_format_little_endian(format);
293	if (val < 0)
294		return val;
295	return !val;
296}
297
298EXPORT_SYMBOL(snd_pcm_format_big_endian);
299
300/**
301 * snd_pcm_format_width - return the bit-width of the format
302 * @format: the format to check
303 *
304 * Returns the bit-width of the format, or a negative error code
305 * if unknown format.
306 */
307int snd_pcm_format_width(snd_pcm_format_t format)
308{
309	int val;
310	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
311		return -EINVAL;
312	if ((val = pcm_formats[(INT)format].width) == 0)
313		return -EINVAL;
314	return val;
315}
316
317EXPORT_SYMBOL(snd_pcm_format_width);
318
319/**
320 * snd_pcm_format_physical_width - return the physical bit-width of the format
321 * @format: the format to check
322 *
323 * Returns the physical bit-width of the format, or a negative error code
324 * if unknown format.
325 */
326int snd_pcm_format_physical_width(snd_pcm_format_t format)
327{
328	int val;
329	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
330		return -EINVAL;
331	if ((val = pcm_formats[(INT)format].phys) == 0)
332		return -EINVAL;
333	return val;
334}
335
336EXPORT_SYMBOL(snd_pcm_format_physical_width);
337
338/**
339 * snd_pcm_format_size - return the byte size of samples on the given format
340 * @format: the format to check
341 * @samples: sampling rate
342 *
343 * Returns the byte size of the given samples for the format, or a
344 * negative error code if unknown format.
345 */
346ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples)
347{
348	int phys_width = snd_pcm_format_physical_width(format);
349	if (phys_width < 0)
350		return -EINVAL;
351	return samples * phys_width / 8;
352}
353
354EXPORT_SYMBOL(snd_pcm_format_size);
355
356/**
357 * snd_pcm_format_silence_64 - return the silent data in 8 bytes array
358 * @format: the format to check
359 *
360 * Returns the format pattern to fill or NULL if error.
361 */
362const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format)
363{
364	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
365		return NULL;
366	if (! pcm_formats[(INT)format].phys)
367		return NULL;
368	return pcm_formats[(INT)format].silence;
369}
370
371EXPORT_SYMBOL(snd_pcm_format_silence_64);
372
373/**
374 * snd_pcm_format_set_silence - set the silence data on the buffer
375 * @format: the PCM format
376 * @data: the buffer pointer
377 * @samples: the number of samples to set silence
378 *
379 * Sets the silence data on the buffer for the given samples.
380 *
381 * Returns zero if successful, or a negative error code on failure.
382 */
383int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples)
384{
385	int width;
386	unsigned char *dst, *pat;
387
388	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
389		return -EINVAL;
390	if (samples == 0)
391		return 0;
392	width = pcm_formats[(INT)format].phys; /* physical width */
393	pat = pcm_formats[(INT)format].silence;
394	if (! width)
395		return -EINVAL;
396	/* signed or 1 byte data */
397	if (pcm_formats[(INT)format].signd == 1 || width <= 8) {
398		unsigned int bytes = samples * width / 8;
399		memset(data, *pat, bytes);
400		return 0;
401	}
402	/* non-zero samples, fill using a loop */
403	width /= 8;
404	dst = data;
405#if 0
406	while (samples--) {
407		memcpy(dst, pat, width);
408		dst += width;
409	}
410#else
411	/* a bit optimization for constant width */
412	switch (width) {
413	case 2:
414		while (samples--) {
415			memcpy(dst, pat, 2);
416			dst += 2;
417		}
418		break;
419	case 3:
420		while (samples--) {
421			memcpy(dst, pat, 3);
422			dst += 3;
423		}
424		break;
425	case 4:
426		while (samples--) {
427			memcpy(dst, pat, 4);
428			dst += 4;
429		}
430		break;
431	case 8:
432		while (samples--) {
433			memcpy(dst, pat, 8);
434			dst += 8;
435		}
436		break;
437	}
438#endif
439	return 0;
440}
441
442EXPORT_SYMBOL(snd_pcm_format_set_silence);
443
444/**
445 * snd_pcm_limit_hw_rates - determine rate_min/rate_max fields
446 * @runtime: the runtime instance
447 *
448 * Determines the rate_min and rate_max fields from the rates bits of
449 * the given runtime->hw.
450 *
451 * Returns zero if successful.
452 */
453int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime)
454{
455	int i;
456	for (i = 0; i < (int)snd_pcm_known_rates.count; i++) {
457		if (runtime->hw.rates & (1 << i)) {
458			runtime->hw.rate_min = snd_pcm_known_rates.list[i];
459			break;
460		}
461	}
462	for (i = (int)snd_pcm_known_rates.count - 1; i >= 0; i--) {
463		if (runtime->hw.rates & (1 << i)) {
464			runtime->hw.rate_max = snd_pcm_known_rates.list[i];
465			break;
466		}
467	}
468	return 0;
469}
470
471EXPORT_SYMBOL(snd_pcm_limit_hw_rates);
472
473/**
474 * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit
475 * @rate: the sample rate to convert
476 *
477 * Returns the SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or
478 * SNDRV_PCM_RATE_KNOT for an unknown rate.
479 */
480unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate)
481{
482	unsigned int i;
483
484	for (i = 0; i < snd_pcm_known_rates.count; i++)
485		if (snd_pcm_known_rates.list[i] == rate)
486			return 1u << i;
487	return SNDRV_PCM_RATE_KNOT;
488}
489EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit);