2 * PCM Interface - misc routines
3 * Copyright (c) 1998 by Jaroslav Kysela <perex@perex.cz>
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.
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.
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
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)
28 /* NOTE: "signed" prefix must be given below since the default char is
29 * unsigned on some architectures!
31 struct 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 */
39 /* we do lots of calculations on snd_pcm_format_t; shut up sparse */
40 #define INT __force int
42 static 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,
47 [SNDRV_PCM_FORMAT_U8] = {
48 .width = 8, .phys = 8, .le = -1, .signd = 0,
51 [SNDRV_PCM_FORMAT_S16_LE] = {
52 .width = 16, .phys = 16, .le = 1, .signd = 1,
55 [SNDRV_PCM_FORMAT_S16_BE] = {
56 .width = 16, .phys = 16, .le = 0, .signd = 1,
59 [SNDRV_PCM_FORMAT_U16_LE] = {
60 .width = 16, .phys = 16, .le = 1, .signd = 0,
61 .silence = { 0x00, 0x80 },
63 [SNDRV_PCM_FORMAT_U16_BE] = {
64 .width = 16, .phys = 16, .le = 0, .signd = 0,
65 .silence = { 0x80, 0x00 },
67 [SNDRV_PCM_FORMAT_S24_LE] = {
68 .width = 24, .phys = 32, .le = 1, .signd = 1,
71 [SNDRV_PCM_FORMAT_S24_BE] = {
72 .width = 24, .phys = 32, .le = 0, .signd = 1,
75 [SNDRV_PCM_FORMAT_U24_LE] = {
76 .width = 24, .phys = 32, .le = 1, .signd = 0,
77 .silence = { 0x00, 0x00, 0x80 },
79 [SNDRV_PCM_FORMAT_U24_BE] = {
80 .width = 24, .phys = 32, .le = 0, .signd = 0,
81 .silence = { 0x00, 0x80, 0x00, 0x00 },
83 [SNDRV_PCM_FORMAT_S32_LE] = {
84 .width = 32, .phys = 32, .le = 1, .signd = 1,
87 [SNDRV_PCM_FORMAT_S32_BE] = {
88 .width = 32, .phys = 32, .le = 0, .signd = 1,
91 [SNDRV_PCM_FORMAT_U32_LE] = {
92 .width = 32, .phys = 32, .le = 1, .signd = 0,
93 .silence = { 0x00, 0x00, 0x00, 0x80 },
95 [SNDRV_PCM_FORMAT_U32_BE] = {
96 .width = 32, .phys = 32, .le = 0, .signd = 0,
97 .silence = { 0x80, 0x00, 0x00, 0x00 },
99 [SNDRV_PCM_FORMAT_FLOAT_LE] = {
100 .width = 32, .phys = 32, .le = 1, .signd = -1,
103 [SNDRV_PCM_FORMAT_FLOAT_BE] = {
104 .width = 32, .phys = 32, .le = 0, .signd = -1,
107 [SNDRV_PCM_FORMAT_FLOAT64_LE] = {
108 .width = 64, .phys = 64, .le = 1, .signd = -1,
111 [SNDRV_PCM_FORMAT_FLOAT64_BE] = {
112 .width = 64, .phys = 64, .le = 0, .signd = -1,
115 [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE] = {
116 .width = 32, .phys = 32, .le = 1, .signd = -1,
119 [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE] = {
120 .width = 32, .phys = 32, .le = 0, .signd = -1,
123 [SNDRV_PCM_FORMAT_MU_LAW] = {
124 .width = 8, .phys = 8, .le = -1, .signd = -1,
127 [SNDRV_PCM_FORMAT_A_LAW] = {
128 .width = 8, .phys = 8, .le = -1, .signd = -1,
131 [SNDRV_PCM_FORMAT_IMA_ADPCM] = {
132 .width = 4, .phys = 4, .le = -1, .signd = -1,
135 [SNDRV_PCM_FORMAT_G723_24] = {
136 .width = 3, .phys = 3, .le = -1, .signd = -1,
139 [SNDRV_PCM_FORMAT_G723_40] = {
140 .width = 5, .phys = 5, .le = -1, .signd = -1,
143 [SNDRV_PCM_FORMAT_DSD_U8] = {
144 .width = 8, .phys = 8, .le = 1, .signd = 0,
147 [SNDRV_PCM_FORMAT_DSD_U16_LE] = {
148 .width = 16, .phys = 16, .le = 1, .signd = 0,
149 .silence = { 0x69, 0x69 },
151 [SNDRV_PCM_FORMAT_DSD_U32_LE] = {
152 .width = 32, .phys = 32, .le = 1, .signd = 0,
153 .silence = { 0x69, 0x69, 0x69, 0x69 },
155 /* FIXME: the following three formats are not defined properly yet */
156 [SNDRV_PCM_FORMAT_MPEG] = {
157 .le = -1, .signd = -1,
159 [SNDRV_PCM_FORMAT_GSM] = {
160 .le = -1, .signd = -1,
162 [SNDRV_PCM_FORMAT_SPECIAL] = {
163 .le = -1, .signd = -1,
165 [SNDRV_PCM_FORMAT_S24_3LE] = {
166 .width = 24, .phys = 24, .le = 1, .signd = 1,
169 [SNDRV_PCM_FORMAT_S24_3BE] = {
170 .width = 24, .phys = 24, .le = 0, .signd = 1,
173 [SNDRV_PCM_FORMAT_U24_3LE] = {
174 .width = 24, .phys = 24, .le = 1, .signd = 0,
175 .silence = { 0x00, 0x00, 0x80 },
177 [SNDRV_PCM_FORMAT_U24_3BE] = {
178 .width = 24, .phys = 24, .le = 0, .signd = 0,
179 .silence = { 0x80, 0x00, 0x00 },
181 [SNDRV_PCM_FORMAT_S20_3LE] = {
182 .width = 20, .phys = 24, .le = 1, .signd = 1,
185 [SNDRV_PCM_FORMAT_S20_3BE] = {
186 .width = 20, .phys = 24, .le = 0, .signd = 1,
189 [SNDRV_PCM_FORMAT_U20_3LE] = {
190 .width = 20, .phys = 24, .le = 1, .signd = 0,
191 .silence = { 0x00, 0x00, 0x08 },
193 [SNDRV_PCM_FORMAT_U20_3BE] = {
194 .width = 20, .phys = 24, .le = 0, .signd = 0,
195 .silence = { 0x08, 0x00, 0x00 },
197 [SNDRV_PCM_FORMAT_S18_3LE] = {
198 .width = 18, .phys = 24, .le = 1, .signd = 1,
201 [SNDRV_PCM_FORMAT_S18_3BE] = {
202 .width = 18, .phys = 24, .le = 0, .signd = 1,
205 [SNDRV_PCM_FORMAT_U18_3LE] = {
206 .width = 18, .phys = 24, .le = 1, .signd = 0,
207 .silence = { 0x00, 0x00, 0x02 },
209 [SNDRV_PCM_FORMAT_U18_3BE] = {
210 .width = 18, .phys = 24, .le = 0, .signd = 0,
211 .silence = { 0x02, 0x00, 0x00 },
213 [SNDRV_PCM_FORMAT_G723_24_1B] = {
214 .width = 3, .phys = 8, .le = -1, .signd = -1,
217 [SNDRV_PCM_FORMAT_G723_40_1B] = {
218 .width = 5, .phys = 8, .le = -1, .signd = -1,
225 * snd_pcm_format_signed - Check the PCM format is signed linear
226 * @format: the format to check
228 * Return: 1 if the given PCM format is signed linear, 0 if unsigned
229 * linear, and a negative error code for non-linear formats.
231 int snd_pcm_format_signed(snd_pcm_format_t format)
234 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
236 if ((val = pcm_formats[(INT)format].signd) < 0)
241 EXPORT_SYMBOL(snd_pcm_format_signed);
244 * snd_pcm_format_unsigned - Check the PCM format is unsigned linear
245 * @format: the format to check
247 * Return: 1 if the given PCM format is unsigned linear, 0 if signed
248 * linear, and a negative error code for non-linear formats.
250 int snd_pcm_format_unsigned(snd_pcm_format_t format)
254 val = snd_pcm_format_signed(format);
260 EXPORT_SYMBOL(snd_pcm_format_unsigned);
263 * snd_pcm_format_linear - Check the PCM format is linear
264 * @format: the format to check
266 * Return: 1 if the given PCM format is linear, 0 if not.
268 int snd_pcm_format_linear(snd_pcm_format_t format)
270 return snd_pcm_format_signed(format) >= 0;
273 EXPORT_SYMBOL(snd_pcm_format_linear);
276 * snd_pcm_format_little_endian - Check the PCM format is little-endian
277 * @format: the format to check
279 * Return: 1 if the given PCM format is little-endian, 0 if
280 * big-endian, or a negative error code if endian not specified.
282 int snd_pcm_format_little_endian(snd_pcm_format_t format)
285 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
287 if ((val = pcm_formats[(INT)format].le) < 0)
292 EXPORT_SYMBOL(snd_pcm_format_little_endian);
295 * snd_pcm_format_big_endian - Check the PCM format is big-endian
296 * @format: the format to check
298 * Return: 1 if the given PCM format is big-endian, 0 if
299 * little-endian, or a negative error code if endian not specified.
301 int snd_pcm_format_big_endian(snd_pcm_format_t format)
305 val = snd_pcm_format_little_endian(format);
311 EXPORT_SYMBOL(snd_pcm_format_big_endian);
314 * snd_pcm_format_width - return the bit-width of the format
315 * @format: the format to check
317 * Return: The bit-width of the format, or a negative error code
320 int snd_pcm_format_width(snd_pcm_format_t format)
323 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
325 if ((val = pcm_formats[(INT)format].width) == 0)
330 EXPORT_SYMBOL(snd_pcm_format_width);
333 * snd_pcm_format_physical_width - return the physical bit-width of the format
334 * @format: the format to check
336 * Return: The physical bit-width of the format, or a negative error code
339 int snd_pcm_format_physical_width(snd_pcm_format_t format)
342 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
344 if ((val = pcm_formats[(INT)format].phys) == 0)
349 EXPORT_SYMBOL(snd_pcm_format_physical_width);
352 * snd_pcm_format_size - return the byte size of samples on the given format
353 * @format: the format to check
354 * @samples: sampling rate
356 * Return: The byte size of the given samples for the format, or a
357 * negative error code if unknown format.
359 ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples)
361 int phys_width = snd_pcm_format_physical_width(format);
364 return samples * phys_width / 8;
367 EXPORT_SYMBOL(snd_pcm_format_size);
370 * snd_pcm_format_silence_64 - return the silent data in 8 bytes array
371 * @format: the format to check
373 * Return: The format pattern to fill or %NULL if error.
375 const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format)
377 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
379 if (! pcm_formats[(INT)format].phys)
381 return pcm_formats[(INT)format].silence;
384 EXPORT_SYMBOL(snd_pcm_format_silence_64);
387 * snd_pcm_format_set_silence - set the silence data on the buffer
388 * @format: the PCM format
389 * @data: the buffer pointer
390 * @samples: the number of samples to set silence
392 * Sets the silence data on the buffer for the given samples.
394 * Return: Zero if successful, or a negative error code on failure.
396 int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples)
399 unsigned char *dst, *pat;
401 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
405 width = pcm_formats[(INT)format].phys; /* physical width */
406 pat = pcm_formats[(INT)format].silence;
409 /* signed or 1 byte data */
410 if (pcm_formats[(INT)format].signd == 1 || width <= 8) {
411 unsigned int bytes = samples * width / 8;
412 memset(data, *pat, bytes);
415 /* non-zero samples, fill using a loop */
420 memcpy(dst, pat, width);
424 /* a bit optimization for constant width */
455 EXPORT_SYMBOL(snd_pcm_format_set_silence);
458 * snd_pcm_limit_hw_rates - determine rate_min/rate_max fields
459 * @runtime: the runtime instance
461 * Determines the rate_min and rate_max fields from the rates bits of
462 * the given runtime->hw.
464 * Return: Zero if successful.
466 int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime)
469 for (i = 0; i < (int)snd_pcm_known_rates.count; i++) {
470 if (runtime->hw.rates & (1 << i)) {
471 runtime->hw.rate_min = snd_pcm_known_rates.list[i];
475 for (i = (int)snd_pcm_known_rates.count - 1; i >= 0; i--) {
476 if (runtime->hw.rates & (1 << i)) {
477 runtime->hw.rate_max = snd_pcm_known_rates.list[i];
484 EXPORT_SYMBOL(snd_pcm_limit_hw_rates);
487 * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit
488 * @rate: the sample rate to convert
490 * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or
491 * SNDRV_PCM_RATE_KNOT for an unknown rate.
493 unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate)
497 for (i = 0; i < snd_pcm_known_rates.count; i++)
498 if (snd_pcm_known_rates.list[i] == rate)
500 return SNDRV_PCM_RATE_KNOT;
502 EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit);
505 * snd_pcm_rate_bit_to_rate - converts SNDRV_PCM_RATE_xxx bit to sample rate
506 * @rate_bit: the rate bit to convert
508 * Return: The sample rate that corresponds to the given SNDRV_PCM_RATE_xxx flag
509 * or 0 for an unknown rate bit.
511 unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit)
515 for (i = 0; i < snd_pcm_known_rates.count; i++)
516 if ((1u << i) == rate_bit)
517 return snd_pcm_known_rates.list[i];
520 EXPORT_SYMBOL(snd_pcm_rate_bit_to_rate);
522 static unsigned int snd_pcm_rate_mask_sanitize(unsigned int rates)
524 if (rates & SNDRV_PCM_RATE_CONTINUOUS)
525 return SNDRV_PCM_RATE_CONTINUOUS;
526 else if (rates & SNDRV_PCM_RATE_KNOT)
527 return SNDRV_PCM_RATE_KNOT;
532 * snd_pcm_rate_mask_intersect - computes the intersection between two rate masks
533 * @rates_a: The first rate mask
534 * @rates_b: The second rate mask
536 * This function computes the rates that are supported by both rate masks passed
537 * to the function. It will take care of the special handling of
538 * SNDRV_PCM_RATE_CONTINUOUS and SNDRV_PCM_RATE_KNOT.
540 * Return: A rate mask containing the rates that are supported by both rates_a
543 unsigned int snd_pcm_rate_mask_intersect(unsigned int rates_a,
544 unsigned int rates_b)
546 rates_a = snd_pcm_rate_mask_sanitize(rates_a);
547 rates_b = snd_pcm_rate_mask_sanitize(rates_b);
549 if (rates_a & SNDRV_PCM_RATE_CONTINUOUS)
551 else if (rates_b & SNDRV_PCM_RATE_CONTINUOUS)
553 else if (rates_a & SNDRV_PCM_RATE_KNOT)
555 else if (rates_b & SNDRV_PCM_RATE_KNOT)
557 return rates_a & rates_b;
559 EXPORT_SYMBOL_GPL(snd_pcm_rate_mask_intersect);