sound/core/pcm_misc.c

   1 /*
   2  *  PCM Interface - misc routines
   3  *  Copyright (c) 1998 by Jaroslav Kysela <perex@suse.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 <sound/driver.h>
  23 #include <linux/time.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 static struct pcm_format_data pcm_formats[SNDRV_PCM_FORMAT_LAST+1] = {
  40         [SNDRV_PCM_FORMAT_S8] = {
  41                 .width = 8, .phys = 8, .le = -1, .signd = 1,
  42                 .silence = {},
  43         },
  44         [SNDRV_PCM_FORMAT_U8] = {
  45                 .width = 8, .phys = 8, .le = -1, .signd = 0,
  46                 .silence = { 0x80 },
  47         },
  48         [SNDRV_PCM_FORMAT_S16_LE] = {
  49                 .width = 16, .phys = 16, .le = 1, .signd = 1,
  50                 .silence = {},
  51         },
  52         [SNDRV_PCM_FORMAT_S16_BE] = {
  53                 .width = 16, .phys = 16, .le = 0, .signd = 1,
  54                 .silence = {},
  55         },
  56         [SNDRV_PCM_FORMAT_U16_LE] = {
  57                 .width = 16, .phys = 16, .le = 1, .signd = 0,
  58                 .silence = { 0x00, 0x80 },
  59         },
  60         [SNDRV_PCM_FORMAT_U16_BE] = {
  61                 .width = 16, .phys = 16, .le = 0, .signd = 0,
  62                 .silence = { 0x80, 0x00 },
  63         },
  64         [SNDRV_PCM_FORMAT_S24_LE] = {
  65                 .width = 24, .phys = 32, .le = 1, .signd = 1,
  66                 .silence = {},
  67         },
  68         [SNDRV_PCM_FORMAT_S24_BE] = {
  69                 .width = 24, .phys = 32, .le = 0, .signd = 1,
  70                 .silence = {},
  71         },
  72         [SNDRV_PCM_FORMAT_U24_LE] = {
  73                 .width = 24, .phys = 32, .le = 1, .signd = 0,
  74                 .silence = { 0x00, 0x00, 0x80 },
  75         },
  76         [SNDRV_PCM_FORMAT_U24_BE] = {
  77                 .width = 24, .phys = 32, .le = 0, .signd = 0,
  78                 .silence = { 0x80, 0x00, 0x00 },
  79         },
  80         [SNDRV_PCM_FORMAT_S32_LE] = {
  81                 .width = 32, .phys = 32, .le = 1, .signd = 1,
  82                 .silence = {},
  83         },
  84         [SNDRV_PCM_FORMAT_S32_BE] = {
  85                 .width = 32, .phys = 32, .le = 0, .signd = 1,
  86                 .silence = {},
  87         },
  88         [SNDRV_PCM_FORMAT_U32_LE] = {
  89                 .width = 32, .phys = 32, .le = 1, .signd = 0,
  90                 .silence = { 0x00, 0x00, 0x00, 0x80 },
  91         },
  92         [SNDRV_PCM_FORMAT_U32_BE] = {
  93                 .width = 32, .phys = 32, .le = 0, .signd = 0,
  94                 .silence = { 0x80, 0x00, 0x00, 0x00 },
  95         },
  96         [SNDRV_PCM_FORMAT_FLOAT_LE] = {
  97                 .width = 32, .phys = 32, .le = 1, .signd = -1,
  98                 .silence = {},
  99         },
 100         [SNDRV_PCM_FORMAT_FLOAT_BE] = {
 101                 .width = 32, .phys = 32, .le = 0, .signd = -1,
 102                 .silence = {},
 103         },
 104         [SNDRV_PCM_FORMAT_FLOAT64_LE] = {
 105                 .width = 64, .phys = 64, .le = 1, .signd = -1,
 106                 .silence = {},
 107         },
 108         [SNDRV_PCM_FORMAT_FLOAT64_BE] = {
 109                 .width = 64, .phys = 64, .le = 0, .signd = -1,
 110                 .silence = {},
 111         },
 112         [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE] = {
 113                 .width = 32, .phys = 32, .le = 1, .signd = -1,
 114                 .silence = {},
 115         },
 116         [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE] = {
 117                 .width = 32, .phys = 32, .le = 0, .signd = -1,
 118                 .silence = {},
 119         },
 120         [SNDRV_PCM_FORMAT_MU_LAW] = {
 121                 .width = 8, .phys = 8, .le = -1, .signd = -1,
 122                 .silence = { 0x7f },
 123         },
 124         [SNDRV_PCM_FORMAT_A_LAW] = {
 125                 .width = 8, .phys = 8, .le = -1, .signd = -1,
 126                 .silence = { 0x55 },
 127         },
 128         [SNDRV_PCM_FORMAT_IMA_ADPCM] = {
 129                 .width = 4, .phys = 4, .le = -1, .signd = -1,
 130                 .silence = {},
 131         },
 132         /* FIXME: the following three formats are not defined properly yet */
 133         [SNDRV_PCM_FORMAT_MPEG] = {
 134                 .le = -1, .signd = -1,
 135         },
 136         [SNDRV_PCM_FORMAT_GSM] = {
 137                 .le = -1, .signd = -1,
 138         },
 139         [SNDRV_PCM_FORMAT_SPECIAL] = {
 140                 .le = -1, .signd = -1,
 141         },
 142         [SNDRV_PCM_FORMAT_S24_3LE] = {
 143                 .width = 24, .phys = 24, .le = 1, .signd = 1,
 144                 .silence = {},
 145         },
 146         [SNDRV_PCM_FORMAT_S24_3BE] = {
 147                 .width = 24, .phys = 24, .le = 0, .signd = 1,
 148                 .silence = {},
 149         },
 150         [SNDRV_PCM_FORMAT_U24_3LE] = {
 151                 .width = 24, .phys = 24, .le = 1, .signd = 0,
 152                 .silence = { 0x00, 0x00, 0x80 },
 153         },
 154         [SNDRV_PCM_FORMAT_U24_3BE] = {
 155                 .width = 24, .phys = 24, .le = 0, .signd = 0,
 156                 .silence = { 0x80, 0x00, 0x00 },
 157         },
 158         [SNDRV_PCM_FORMAT_S20_3LE] = {
 159                 .width = 20, .phys = 24, .le = 1, .signd = 1,
 160                 .silence = {},
 161         },
 162         [SNDRV_PCM_FORMAT_S20_3BE] = {
 163                 .width = 20, .phys = 24, .le = 0, .signd = 1,
 164                 .silence = {},
 165         },
 166         [SNDRV_PCM_FORMAT_U20_3LE] = {
 167                 .width = 20, .phys = 24, .le = 1, .signd = 0,
 168                 .silence = { 0x00, 0x00, 0x08 },
 169         },
 170         [SNDRV_PCM_FORMAT_U20_3BE] = {
 171                 .width = 20, .phys = 24, .le = 0, .signd = 0,
 172                 .silence = { 0x08, 0x00, 0x00 },
 173         },
 174         [SNDRV_PCM_FORMAT_S18_3LE] = {
 175                 .width = 18, .phys = 24, .le = 1, .signd = 1,
 176                 .silence = {},
 177         },
 178         [SNDRV_PCM_FORMAT_S18_3BE] = {
 179                 .width = 18, .phys = 24, .le = 0, .signd = 1,
 180                 .silence = {},
 181         },
 182         [SNDRV_PCM_FORMAT_U18_3LE] = {
 183                 .width = 18, .phys = 24, .le = 1, .signd = 0,
 184                 .silence = { 0x00, 0x00, 0x02 },
 185         },
 186         [SNDRV_PCM_FORMAT_U18_3BE] = {
 187                 .width = 18, .phys = 24, .le = 0, .signd = 0,
 188                 .silence = { 0x02, 0x00, 0x00 },
 189         },
 190 };
 191
 192
 193 /**
 194  * snd_pcm_format_signed - Check the PCM format is signed linear
 195  * @format: the format to check
 196  *
 197  * Returns 1 if the given PCM format is signed linear, 0 if unsigned
 198  * linear, and a negative error code for non-linear formats.
 199  */
 200 int snd_pcm_format_signed(snd_pcm_format_t format)
 201 {
 202         int val;
 203         if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
 204                 return -EINVAL;
 205         if ((val = pcm_formats[format].signd) < 0)
 206                 return -EINVAL;
 207         return val;
 208 }
 209
 210 EXPORT_SYMBOL(snd_pcm_format_signed);
 211
 212 /**
 213  * snd_pcm_format_unsigned - Check the PCM format is unsigned linear
 214  * @format: the format to check
 215  *
 216  * Returns 1 if the given PCM format is unsigned linear, 0 if signed
 217  * linear, and a negative error code for non-linear formats.
 218  */
 219 int snd_pcm_format_unsigned(snd_pcm_format_t format)
 220 {
 221         int val;
 222
 223         val = snd_pcm_format_signed(format);
 224         if (val < 0)
 225                 return val;
 226         return !val;
 227 }
 228
 229 EXPORT_SYMBOL(snd_pcm_format_unsigned);
 230
 231 /**
 232  * snd_pcm_format_linear - Check the PCM format is linear
 233  * @format: the format to check
 234  *
 235  * Returns 1 if the given PCM format is linear, 0 if not.
 236  */
 237 int snd_pcm_format_linear(snd_pcm_format_t format)
 238 {
 239         return snd_pcm_format_signed(format) >= 0;
 240 }
 241
 242 EXPORT_SYMBOL(snd_pcm_format_linear);
 243
 244 /**
 245  * snd_pcm_format_little_endian - Check the PCM format is little-endian
 246  * @format: the format to check
 247  *
 248  * Returns 1 if the given PCM format is little-endian, 0 if
 249  * big-endian, or a negative error code if endian not specified.
 250  */
 251 int snd_pcm_format_little_endian(snd_pcm_format_t format)
 252 {
 253         int val;
 254         if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
 255                 return -EINVAL;
 256         if ((val = pcm_formats[format].le) < 0)
 257                 return -EINVAL;
 258         return val;
 259 }
 260
 261 EXPORT_SYMBOL(snd_pcm_format_little_endian);
 262
 263 /**
 264  * snd_pcm_format_big_endian - Check the PCM format is big-endian
 265  * @format: the format to check
 266  *
 267  * Returns 1 if the given PCM format is big-endian, 0 if
 268  * little-endian, or a negative error code if endian not specified.
 269  */
 270 int snd_pcm_format_big_endian(snd_pcm_format_t format)
 271 {
 272         int val;
 273
 274         val = snd_pcm_format_little_endian(format);
 275         if (val < 0)
 276                 return val;
 277         return !val;
 278 }
 279
 280 EXPORT_SYMBOL(snd_pcm_format_big_endian);
 281
 282 /**
 283  * snd_pcm_format_width - return the bit-width of the format
 284  * @format: the format to check
 285  *
 286  * Returns the bit-width of the format, or a negative error code
 287  * if unknown format.
 288  */
 289 int snd_pcm_format_width(snd_pcm_format_t format)
 290 {
 291         int val;
 292         if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
 293                 return -EINVAL;
 294         if ((val = pcm_formats[format].width) == 0)
 295                 return -EINVAL;
 296         return val;
 297 }
 298
 299 EXPORT_SYMBOL(snd_pcm_format_width);
 300
 301 /**
 302  * snd_pcm_format_physical_width - return the physical bit-width of the format
 303  * @format: the format to check
 304  *
 305  * Returns the physical bit-width of the format, or a negative error code
 306  * if unknown format.
 307  */
 308 int snd_pcm_format_physical_width(snd_pcm_format_t format)
 309 {
 310         int val;
 311         if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
 312                 return -EINVAL;
 313         if ((val = pcm_formats[format].phys) == 0)
 314                 return -EINVAL;
 315         return val;
 316 }
 317
 318 EXPORT_SYMBOL(snd_pcm_format_physical_width);
 319
 320 /**
 321  * snd_pcm_format_size - return the byte size of samples on the given format
 322  * @format: the format to check
 323  *
 324  * Returns the byte size of the given samples for the format, or a
 325  * negative error code if unknown format.
 326  */
 327 ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples)
 328 {
 329         int phys_width = snd_pcm_format_physical_width(format);
 330         if (phys_width < 0)
 331                 return -EINVAL;
 332         return samples * phys_width / 8;
 333 }
 334
 335 EXPORT_SYMBOL(snd_pcm_format_size);
 336
 337 /**
 338  * snd_pcm_format_silence_64 - return the silent data in 8 bytes array
 339  * @format: the format to check
 340  *
 341  * Returns the format pattern to fill or NULL if error.
 342  */
 343 const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format)
 344 {
 345         if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
 346                 return NULL;
 347         if (! pcm_formats[format].phys)
 348                 return NULL;
 349         return pcm_formats[format].silence;
 350 }
 351
 352 EXPORT_SYMBOL(snd_pcm_format_silence_64);
 353
 354 /**
 355  * snd_pcm_format_set_silence - set the silence data on the buffer
 356  * @format: the PCM format
 357  * @data: the buffer pointer
 358  * @samples: the number of samples to set silence
 359  *
 360  * Sets the silence data on the buffer for the given samples.
 361  *
 362  * Returns zero if successful, or a negative error code on failure.
 363  */
 364 int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples)
 365 {
 366         int width;
 367         unsigned char *dst, *pat;
 368
 369         if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
 370                 return -EINVAL;
 371         if (samples == 0)
 372                 return 0;
 373         width = pcm_formats[format].phys; /* physical width */
 374         pat = pcm_formats[format].silence;
 375         if (! width)
 376                 return -EINVAL;
 377         /* signed or 1 byte data */
 378         if (pcm_formats[format].signd == 1 || width <= 8) {
 379                 unsigned int bytes = samples * width / 8;
 380                 memset(data, *pat, bytes);
 381                 return 0;
 382         }
 383         /* non-zero samples, fill using a loop */
 384         width /= 8;
 385         dst = data;
 386 #if 0
 387         while (samples--) {
 388                 memcpy(dst, pat, width);
 389                 dst += width;
 390         }
 391 #else
 392         /* a bit optimization for constant width */
 393         switch (width) {
 394         case 2:
 395                 while (samples--) {
 396                         memcpy(dst, pat, 2);
 397                         dst += 2;
 398                 }
 399                 break;
 400         case 3:
 401                 while (samples--) {
 402                         memcpy(dst, pat, 3);
 403                         dst += 3;
 404                 }
 405                 break;
 406         case 4:
 407                 while (samples--) {
 408                         memcpy(dst, pat, 4);
 409                         dst += 4;
 410                 }
 411                 break;
 412         case 8:
 413                 while (samples--) {
 414                         memcpy(dst, pat, 8);
 415                         dst += 8;
 416                 }
 417                 break;
 418         }
 419 #endif
 420         return 0;
 421 }
 422
 423 EXPORT_SYMBOL(snd_pcm_format_set_silence);
 424
 425 /* [width][unsigned][bigendian] */
 426 static int linear_formats[4][2][2] = {
 427         {{ SNDRV_PCM_FORMAT_S8, SNDRV_PCM_FORMAT_S8},
 428          { SNDRV_PCM_FORMAT_U8, SNDRV_PCM_FORMAT_U8}},
 429         {{SNDRV_PCM_FORMAT_S16_LE, SNDRV_PCM_FORMAT_S16_BE},
 430          {SNDRV_PCM_FORMAT_U16_LE, SNDRV_PCM_FORMAT_U16_BE}},
 431         {{SNDRV_PCM_FORMAT_S24_LE, SNDRV_PCM_FORMAT_S24_BE},
 432          {SNDRV_PCM_FORMAT_U24_LE, SNDRV_PCM_FORMAT_U24_BE}},
 433         {{SNDRV_PCM_FORMAT_S32_LE, SNDRV_PCM_FORMAT_S32_BE},
 434          {SNDRV_PCM_FORMAT_U32_LE, SNDRV_PCM_FORMAT_U32_BE}}
 435 };
 436
 437 /**
 438  * snd_pcm_build_linear_format - return the suitable linear format for the given condition
 439  * @width: the bit-width
 440  * @unsignd: 1 if unsigned, 0 if signed.
 441  * @big_endian: 1 if big-endian, 0 if little-endian
 442  *
 443  * Returns the suitable linear format for the given condition.
 444  */
 445 snd_pcm_format_t snd_pcm_build_linear_format(int width, int unsignd, int big_endian)
 446 {
 447         if (width & 7)
 448                 return SND_PCM_FORMAT_UNKNOWN;
 449         width = (width / 8) - 1;
 450         if (width < 0 || width >= 4)
 451                 return SND_PCM_FORMAT_UNKNOWN;
 452         return linear_formats[width][!!unsignd][!!big_endian];
 453 }
 454
 455 EXPORT_SYMBOL(snd_pcm_build_linear_format);
 456
 457 /**
 458  * snd_pcm_limit_hw_rates - determine rate_min/rate_max fields
 459  * @runtime: the runtime instance
 460  *
 461  * Determines the rate_min and rate_max fields from the rates bits of
 462  * the given runtime->hw.
 463  *
 464  * Returns zero if successful.
 465  */
 466 int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime)
 467 {
 468         static unsigned rates[] = {
 469                 /* ATTENTION: these values depend on the definition in pcm.h! */
 470                 5512, 8000, 11025, 16000, 22050, 32000, 44100, 48000,
 471                 64000, 88200, 96000, 176400, 192000
 472         };
 473         int i;
 474         for (i = 0; i < (int)ARRAY_SIZE(rates); i++) {
 475                 if (runtime->hw.rates & (1 << i)) {
 476                         runtime->hw.rate_min = rates[i];
 477                         break;
 478                 }
 479         }
 480         for (i = (int)ARRAY_SIZE(rates) - 1; i >= 0; i--) {
 481                 if (runtime->hw.rates & (1 << i)) {
 482                         runtime->hw.rate_max = rates[i];
 483                         break;
 484                 }
 485         }
 486         return 0;
 487 }
 488
 489 EXPORT_SYMBOL(snd_pcm_limit_hw_rates);