Linux Audio

Check our new training course

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