619 lines · c
1/*2 * PCM Interface - misc routines3 * Copyright (c) 1998 by Jaroslav Kysela <perex@perex.cz>4 *5 *6 * This library is free software; you can redistribute it and/or modify7 * it under the terms of the GNU Library General Public License as8 * published by the Free Software Foundation; either version 2 of9 * 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 of13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the14 * GNU Library General Public License for more details.15 *16 * You should have received a copy of the GNU Library General Public17 * License along with this library; if not, write to the Free Software18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA19 *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 is32 * 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 int44 45static bool valid_format(snd_pcm_format_t format)46{47 return (INT)format >= 0 && (INT)format <= (INT)SNDRV_PCM_FORMAT_LAST;48}49 50static const struct pcm_format_data pcm_formats[(INT)SNDRV_PCM_FORMAT_LAST+1] = {51 [SNDRV_PCM_FORMAT_S8] = {52 .width = 8, .phys = 8, .le = -1, .signd = 1,53 .silence = {},54 },55 [SNDRV_PCM_FORMAT_U8] = {56 .width = 8, .phys = 8, .le = -1, .signd = 0,57 .silence = { 0x80 },58 },59 [SNDRV_PCM_FORMAT_S16_LE] = {60 .width = 16, .phys = 16, .le = 1, .signd = 1,61 .silence = {},62 },63 [SNDRV_PCM_FORMAT_S16_BE] = {64 .width = 16, .phys = 16, .le = 0, .signd = 1,65 .silence = {},66 },67 [SNDRV_PCM_FORMAT_U16_LE] = {68 .width = 16, .phys = 16, .le = 1, .signd = 0,69 .silence = { 0x00, 0x80 },70 },71 [SNDRV_PCM_FORMAT_U16_BE] = {72 .width = 16, .phys = 16, .le = 0, .signd = 0,73 .silence = { 0x80, 0x00 },74 },75 [SNDRV_PCM_FORMAT_S24_LE] = {76 .width = 24, .phys = 32, .le = 1, .signd = 1,77 .silence = {},78 },79 [SNDRV_PCM_FORMAT_S24_BE] = {80 .width = 24, .phys = 32, .le = 0, .signd = 1,81 .silence = {},82 },83 [SNDRV_PCM_FORMAT_U24_LE] = {84 .width = 24, .phys = 32, .le = 1, .signd = 0,85 .silence = { 0x00, 0x00, 0x80 },86 },87 [SNDRV_PCM_FORMAT_U24_BE] = {88 .width = 24, .phys = 32, .le = 0, .signd = 0,89 .silence = { 0x00, 0x80, 0x00, 0x00 },90 },91 [SNDRV_PCM_FORMAT_S32_LE] = {92 .width = 32, .phys = 32, .le = 1, .signd = 1,93 .silence = {},94 },95 [SNDRV_PCM_FORMAT_S32_BE] = {96 .width = 32, .phys = 32, .le = 0, .signd = 1,97 .silence = {},98 },99 [SNDRV_PCM_FORMAT_U32_LE] = {100 .width = 32, .phys = 32, .le = 1, .signd = 0,101 .silence = { 0x00, 0x00, 0x00, 0x80 },102 },103 [SNDRV_PCM_FORMAT_U32_BE] = {104 .width = 32, .phys = 32, .le = 0, .signd = 0,105 .silence = { 0x80, 0x00, 0x00, 0x00 },106 },107 [SNDRV_PCM_FORMAT_FLOAT_LE] = {108 .width = 32, .phys = 32, .le = 1, .signd = -1,109 .silence = {},110 },111 [SNDRV_PCM_FORMAT_FLOAT_BE] = {112 .width = 32, .phys = 32, .le = 0, .signd = -1,113 .silence = {},114 },115 [SNDRV_PCM_FORMAT_FLOAT64_LE] = {116 .width = 64, .phys = 64, .le = 1, .signd = -1,117 .silence = {},118 },119 [SNDRV_PCM_FORMAT_FLOAT64_BE] = {120 .width = 64, .phys = 64, .le = 0, .signd = -1,121 .silence = {},122 },123 [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE] = {124 .width = 32, .phys = 32, .le = 1, .signd = -1,125 .silence = {},126 },127 [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE] = {128 .width = 32, .phys = 32, .le = 0, .signd = -1,129 .silence = {},130 },131 [SNDRV_PCM_FORMAT_MU_LAW] = {132 .width = 8, .phys = 8, .le = -1, .signd = -1,133 .silence = { 0x7f },134 },135 [SNDRV_PCM_FORMAT_A_LAW] = {136 .width = 8, .phys = 8, .le = -1, .signd = -1,137 .silence = { 0x55 },138 },139 [SNDRV_PCM_FORMAT_IMA_ADPCM] = {140 .width = 4, .phys = 4, .le = -1, .signd = -1,141 .silence = {},142 },143 [SNDRV_PCM_FORMAT_G723_24] = {144 .width = 3, .phys = 3, .le = -1, .signd = -1,145 .silence = {},146 },147 [SNDRV_PCM_FORMAT_G723_40] = {148 .width = 5, .phys = 5, .le = -1, .signd = -1,149 .silence = {},150 },151 [SNDRV_PCM_FORMAT_DSD_U8] = {152 .width = 8, .phys = 8, .le = 1, .signd = 0,153 .silence = { 0x69 },154 },155 [SNDRV_PCM_FORMAT_DSD_U16_LE] = {156 .width = 16, .phys = 16, .le = 1, .signd = 0,157 .silence = { 0x69, 0x69 },158 },159 [SNDRV_PCM_FORMAT_DSD_U32_LE] = {160 .width = 32, .phys = 32, .le = 1, .signd = 0,161 .silence = { 0x69, 0x69, 0x69, 0x69 },162 },163 [SNDRV_PCM_FORMAT_DSD_U16_BE] = {164 .width = 16, .phys = 16, .le = 0, .signd = 0,165 .silence = { 0x69, 0x69 },166 },167 [SNDRV_PCM_FORMAT_DSD_U32_BE] = {168 .width = 32, .phys = 32, .le = 0, .signd = 0,169 .silence = { 0x69, 0x69, 0x69, 0x69 },170 },171 /* FIXME: the following two formats are not defined properly yet */172 [SNDRV_PCM_FORMAT_MPEG] = {173 .le = -1, .signd = -1,174 },175 [SNDRV_PCM_FORMAT_GSM] = {176 .le = -1, .signd = -1,177 },178 [SNDRV_PCM_FORMAT_S20_LE] = {179 .width = 20, .phys = 32, .le = 1, .signd = 1,180 .silence = {},181 },182 [SNDRV_PCM_FORMAT_S20_BE] = {183 .width = 20, .phys = 32, .le = 0, .signd = 1,184 .silence = {},185 },186 [SNDRV_PCM_FORMAT_U20_LE] = {187 .width = 20, .phys = 32, .le = 1, .signd = 0,188 .silence = { 0x00, 0x00, 0x08, 0x00 },189 },190 [SNDRV_PCM_FORMAT_U20_BE] = {191 .width = 20, .phys = 32, .le = 0, .signd = 0,192 .silence = { 0x00, 0x08, 0x00, 0x00 },193 },194 /* FIXME: the following format is not defined properly yet */195 [SNDRV_PCM_FORMAT_SPECIAL] = {196 .le = -1, .signd = -1,197 },198 [SNDRV_PCM_FORMAT_S24_3LE] = {199 .width = 24, .phys = 24, .le = 1, .signd = 1,200 .silence = {},201 },202 [SNDRV_PCM_FORMAT_S24_3BE] = {203 .width = 24, .phys = 24, .le = 0, .signd = 1,204 .silence = {},205 },206 [SNDRV_PCM_FORMAT_U24_3LE] = {207 .width = 24, .phys = 24, .le = 1, .signd = 0,208 .silence = { 0x00, 0x00, 0x80 },209 },210 [SNDRV_PCM_FORMAT_U24_3BE] = {211 .width = 24, .phys = 24, .le = 0, .signd = 0,212 .silence = { 0x80, 0x00, 0x00 },213 },214 [SNDRV_PCM_FORMAT_S20_3LE] = {215 .width = 20, .phys = 24, .le = 1, .signd = 1,216 .silence = {},217 },218 [SNDRV_PCM_FORMAT_S20_3BE] = {219 .width = 20, .phys = 24, .le = 0, .signd = 1,220 .silence = {},221 },222 [SNDRV_PCM_FORMAT_U20_3LE] = {223 .width = 20, .phys = 24, .le = 1, .signd = 0,224 .silence = { 0x00, 0x00, 0x08 },225 },226 [SNDRV_PCM_FORMAT_U20_3BE] = {227 .width = 20, .phys = 24, .le = 0, .signd = 0,228 .silence = { 0x08, 0x00, 0x00 },229 },230 [SNDRV_PCM_FORMAT_S18_3LE] = {231 .width = 18, .phys = 24, .le = 1, .signd = 1,232 .silence = {},233 },234 [SNDRV_PCM_FORMAT_S18_3BE] = {235 .width = 18, .phys = 24, .le = 0, .signd = 1,236 .silence = {},237 },238 [SNDRV_PCM_FORMAT_U18_3LE] = {239 .width = 18, .phys = 24, .le = 1, .signd = 0,240 .silence = { 0x00, 0x00, 0x02 },241 },242 [SNDRV_PCM_FORMAT_U18_3BE] = {243 .width = 18, .phys = 24, .le = 0, .signd = 0,244 .silence = { 0x02, 0x00, 0x00 },245 },246 [SNDRV_PCM_FORMAT_G723_24_1B] = {247 .width = 3, .phys = 8, .le = -1, .signd = -1,248 .silence = {},249 },250 [SNDRV_PCM_FORMAT_G723_40_1B] = {251 .width = 5, .phys = 8, .le = -1, .signd = -1,252 .silence = {},253 },254};255 256 257/**258 * snd_pcm_format_signed - Check the PCM format is signed linear259 * @format: the format to check260 *261 * Return: 1 if the given PCM format is signed linear, 0 if unsigned262 * linear, and a negative error code for non-linear formats.263 */264int snd_pcm_format_signed(snd_pcm_format_t format)265{266 int val;267 if (!valid_format(format))268 return -EINVAL;269 val = pcm_formats[(INT)format].signd;270 if (val < 0)271 return -EINVAL;272 return val;273}274EXPORT_SYMBOL(snd_pcm_format_signed);275 276/**277 * snd_pcm_format_unsigned - Check the PCM format is unsigned linear278 * @format: the format to check279 *280 * Return: 1 if the given PCM format is unsigned linear, 0 if signed281 * linear, and a negative error code for non-linear formats.282 */283int snd_pcm_format_unsigned(snd_pcm_format_t format)284{285 int val;286 287 val = snd_pcm_format_signed(format);288 if (val < 0)289 return val;290 return !val;291}292EXPORT_SYMBOL(snd_pcm_format_unsigned);293 294/**295 * snd_pcm_format_linear - Check the PCM format is linear296 * @format: the format to check297 *298 * Return: 1 if the given PCM format is linear, 0 if not.299 */300int snd_pcm_format_linear(snd_pcm_format_t format)301{302 return snd_pcm_format_signed(format) >= 0;303}304EXPORT_SYMBOL(snd_pcm_format_linear);305 306/**307 * snd_pcm_format_little_endian - Check the PCM format is little-endian308 * @format: the format to check309 *310 * Return: 1 if the given PCM format is little-endian, 0 if311 * big-endian, or a negative error code if endian not specified.312 */313int snd_pcm_format_little_endian(snd_pcm_format_t format)314{315 int val;316 if (!valid_format(format))317 return -EINVAL;318 val = pcm_formats[(INT)format].le;319 if (val < 0)320 return -EINVAL;321 return val;322}323EXPORT_SYMBOL(snd_pcm_format_little_endian);324 325/**326 * snd_pcm_format_big_endian - Check the PCM format is big-endian327 * @format: the format to check328 *329 * Return: 1 if the given PCM format is big-endian, 0 if330 * little-endian, or a negative error code if endian not specified.331 */332int snd_pcm_format_big_endian(snd_pcm_format_t format)333{334 int val;335 336 val = snd_pcm_format_little_endian(format);337 if (val < 0)338 return val;339 return !val;340}341EXPORT_SYMBOL(snd_pcm_format_big_endian);342 343/**344 * snd_pcm_format_width - return the bit-width of the format345 * @format: the format to check346 *347 * Return: The bit-width of the format, or a negative error code348 * if unknown format.349 */350int snd_pcm_format_width(snd_pcm_format_t format)351{352 int val;353 if (!valid_format(format))354 return -EINVAL;355 val = pcm_formats[(INT)format].width;356 if (!val)357 return -EINVAL;358 return val;359}360EXPORT_SYMBOL(snd_pcm_format_width);361 362/**363 * snd_pcm_format_physical_width - return the physical bit-width of the format364 * @format: the format to check365 *366 * Return: The physical bit-width of the format, or a negative error code367 * if unknown format.368 */369int snd_pcm_format_physical_width(snd_pcm_format_t format)370{371 int val;372 if (!valid_format(format))373 return -EINVAL;374 val = pcm_formats[(INT)format].phys;375 if (!val)376 return -EINVAL;377 return val;378}379EXPORT_SYMBOL(snd_pcm_format_physical_width);380 381/**382 * snd_pcm_format_size - return the byte size of samples on the given format383 * @format: the format to check384 * @samples: sampling rate385 *386 * Return: The byte size of the given samples for the format, or a387 * negative error code if unknown format.388 */389ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples)390{391 int phys_width = snd_pcm_format_physical_width(format);392 if (phys_width < 0)393 return -EINVAL;394 return samples * phys_width / 8;395}396EXPORT_SYMBOL(snd_pcm_format_size);397 398/**399 * snd_pcm_format_silence_64 - return the silent data in 8 bytes array400 * @format: the format to check401 *402 * Return: The format pattern to fill or %NULL if error.403 */404const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format)405{406 if (!valid_format(format))407 return NULL;408 if (! pcm_formats[(INT)format].phys)409 return NULL;410 return pcm_formats[(INT)format].silence;411}412EXPORT_SYMBOL(snd_pcm_format_silence_64);413 414/**415 * snd_pcm_format_set_silence - set the silence data on the buffer416 * @format: the PCM format417 * @data: the buffer pointer418 * @samples: the number of samples to set silence419 *420 * Sets the silence data on the buffer for the given samples.421 *422 * Return: Zero if successful, or a negative error code on failure.423 */424int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples)425{426 int width;427 unsigned char *dst;428 const unsigned char *pat;429 430 if (!valid_format(format))431 return -EINVAL;432 if (samples == 0)433 return 0;434 width = pcm_formats[(INT)format].phys; /* physical width */435 pat = pcm_formats[(INT)format].silence;436 if (!width || !pat)437 return -EINVAL;438 /* signed or 1 byte data */439 if (pcm_formats[(INT)format].signd == 1 || width <= 8) {440 unsigned int bytes = samples * width / 8;441 memset(data, *pat, bytes);442 return 0;443 }444 /* non-zero samples, fill using a loop */445 width /= 8;446 dst = data;447#if 0448 while (samples--) {449 memcpy(dst, pat, width);450 dst += width;451 }452#else453 /* a bit optimization for constant width */454 switch (width) {455 case 2:456 while (samples--) {457 memcpy(dst, pat, 2);458 dst += 2;459 }460 break;461 case 3:462 while (samples--) {463 memcpy(dst, pat, 3);464 dst += 3;465 }466 break;467 case 4:468 while (samples--) {469 memcpy(dst, pat, 4);470 dst += 4;471 }472 break;473 case 8:474 while (samples--) {475 memcpy(dst, pat, 8);476 dst += 8;477 }478 break;479 }480#endif481 return 0;482}483EXPORT_SYMBOL(snd_pcm_format_set_silence);484 485/**486 * snd_pcm_hw_limit_rates - determine rate_min/rate_max fields487 * @hw: the pcm hw instance488 *489 * Determines the rate_min and rate_max fields from the rates bits of490 * the given hw.491 *492 * Return: Zero if successful.493 */494int snd_pcm_hw_limit_rates(struct snd_pcm_hardware *hw)495{496 int i;497 unsigned int rmin, rmax;498 499 rmin = UINT_MAX;500 rmax = 0;501 for (i = 0; i < (int)snd_pcm_known_rates.count; i++) {502 if (hw->rates & (1 << i)) {503 rmin = min(rmin, snd_pcm_known_rates.list[i]);504 rmax = max(rmax, snd_pcm_known_rates.list[i]);505 }506 }507 if (rmin > rmax)508 return -EINVAL;509 hw->rate_min = rmin;510 hw->rate_max = rmax;511 return 0;512}513EXPORT_SYMBOL(snd_pcm_hw_limit_rates);514 515/**516 * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit517 * @rate: the sample rate to convert518 *519 * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or520 * SNDRV_PCM_RATE_KNOT for an unknown rate.521 */522unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate)523{524 unsigned int i;525 526 for (i = 0; i < snd_pcm_known_rates.count; i++)527 if (snd_pcm_known_rates.list[i] == rate)528 return 1u << i;529 return SNDRV_PCM_RATE_KNOT;530}531EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit);532 533/**534 * snd_pcm_rate_bit_to_rate - converts SNDRV_PCM_RATE_xxx bit to sample rate535 * @rate_bit: the rate bit to convert536 *537 * Return: The sample rate that corresponds to the given SNDRV_PCM_RATE_xxx flag538 * or 0 for an unknown rate bit.539 */540unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit)541{542 unsigned int i;543 544 for (i = 0; i < snd_pcm_known_rates.count; i++)545 if ((1u << i) == rate_bit)546 return snd_pcm_known_rates.list[i];547 return 0;548}549EXPORT_SYMBOL(snd_pcm_rate_bit_to_rate);550 551static unsigned int snd_pcm_rate_mask_sanitize(unsigned int rates)552{553 if (rates & SNDRV_PCM_RATE_CONTINUOUS)554 return SNDRV_PCM_RATE_CONTINUOUS;555 else if (rates & SNDRV_PCM_RATE_KNOT)556 return SNDRV_PCM_RATE_KNOT;557 return rates;558}559 560/**561 * snd_pcm_rate_mask_intersect - computes the intersection between two rate masks562 * @rates_a: The first rate mask563 * @rates_b: The second rate mask564 *565 * This function computes the rates that are supported by both rate masks passed566 * to the function. It will take care of the special handling of567 * SNDRV_PCM_RATE_CONTINUOUS and SNDRV_PCM_RATE_KNOT.568 *569 * Return: A rate mask containing the rates that are supported by both rates_a570 * and rates_b.571 */572unsigned int snd_pcm_rate_mask_intersect(unsigned int rates_a,573 unsigned int rates_b)574{575 rates_a = snd_pcm_rate_mask_sanitize(rates_a);576 rates_b = snd_pcm_rate_mask_sanitize(rates_b);577 578 if (rates_a & SNDRV_PCM_RATE_CONTINUOUS)579 return rates_b;580 else if (rates_b & SNDRV_PCM_RATE_CONTINUOUS)581 return rates_a;582 else if (rates_a & SNDRV_PCM_RATE_KNOT)583 return rates_b;584 else if (rates_b & SNDRV_PCM_RATE_KNOT)585 return rates_a;586 return rates_a & rates_b;587}588EXPORT_SYMBOL_GPL(snd_pcm_rate_mask_intersect);589 590/**591 * snd_pcm_rate_range_to_bits - converts rate range to SNDRV_PCM_RATE_xxx bit592 * @rate_min: the minimum sample rate593 * @rate_max: the maximum sample rate594 *595 * This function has an implicit assumption: the rates in the given range have596 * only the pre-defined rates like 44100 or 16000.597 *598 * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate range,599 * or SNDRV_PCM_RATE_KNOT for an unknown range.600 */601unsigned int snd_pcm_rate_range_to_bits(unsigned int rate_min,602 unsigned int rate_max)603{604 unsigned int rates = 0;605 int i;606 607 for (i = 0; i < snd_pcm_known_rates.count; i++) {608 if (snd_pcm_known_rates.list[i] >= rate_min609 && snd_pcm_known_rates.list[i] <= rate_max)610 rates |= 1 << i;611 }612 613 if (!rates)614 rates = SNDRV_PCM_RATE_KNOT;615 616 return rates;617}618EXPORT_SYMBOL_GPL(snd_pcm_rate_range_to_bits);619