sound/core/pcm_misc.c

   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  */
  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 */
  37 };
  38
  39 /* we do lots of calculations on snd_pcm_format_t; shut up sparse */
  40 #define INT     __force int
  41
  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,
  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  */
 227 int 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
 237 EXPORT_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  */
 246 int 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
 256 EXPORT_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  */
 264 int snd_pcm_format_linear(snd_pcm_format_t format)
 265 {
 266         return snd_pcm_format_signed(format) >= 0;
 267 }
 268
 269 EXPORT_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  */
 278 int 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
 288 EXPORT_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  */
 297 int 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
 307 EXPORT_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  */
 316 int 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
 326 EXPORT_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  */
 335 int 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
 345 EXPORT_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  */
 355 ssize_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
 363 EXPORT_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  */
 371 const 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
 380 EXPORT_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  */
 392 int 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
 451 EXPORT_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  */
 462 int 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
 480 EXPORT_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  */
 489 unsigned 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 }
 498 EXPORT_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  */
 507 unsigned 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 }
 516 EXPORT_SYMBOL(snd_pcm_rate_bit_to_rate);