release/src-rt-6.x.4708/linux/linux-2.6.36/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 <sound/core.h>
  24 #include <sound/pcm.h>
  25 #define SND_PCM_FORMAT_UNKNOWN (-1)
  26
  27 /* NOTE: "signed" prefix must be given below since the default char is
  28  *       unsigned on some architectures!
  29  */
  30 struct pcm_format_data {
  31         unsigned char width;    /* bit width */
  32         unsigned char phys;     /* physical bit width */
  33         signed char le; /* 0 = big-endian, 1 = little-endian, -1 = others */
  34         signed char signd;      /* 0 = unsigned, 1 = signed, -1 = others */
  35         unsigned char silence[8];       /* silence data to fill */
  36 };
  37
  38 static struct pcm_format_data pcm_formats[SNDRV_PCM_FORMAT_LAST+1] = {
  39         [SNDRV_PCM_FORMAT_S8] = {
  40                 .width = 8, .phys = 8, .le = -1, .signd = 1,
  41                 .silence = {},
  42         },
  43         [SNDRV_PCM_FORMAT_U8] = {
  44                 .width = 8, .phys = 8, .le = -1, .signd = 0,
  45                 .silence = { 0x80 },
  46         },
  47         [SNDRV_PCM_FORMAT_S16_LE] = {
  48                 .width = 16, .phys = 16, .le = 1, .signd = 1,
  49                 .silence = {},
  50         },
  51         [SNDRV_PCM_FORMAT_S16_BE] = {
  52                 .width = 16, .phys = 16, .le = 0, .signd = 1,
  53                 .silence = {},
  54         },
  55         [SNDRV_PCM_FORMAT_U16_LE] = {
  56                 .width = 16, .phys = 16, .le = 1, .signd = 0,
  57                 .silence = { 0x00, 0x80 },
  58         },
  59         [SNDRV_PCM_FORMAT_U16_BE] = {
  60                 .width = 16, .phys = 16, .le = 0, .signd = 0,
  61                 .silence = { 0x80, 0x00 },
  62         },
  63         [SNDRV_PCM_FORMAT_S24_LE] = {
  64                 .width = 24, .phys = 32, .le = 1, .signd = 1,
  65                 .silence = {},
  66         },
  67         [SNDRV_PCM_FORMAT_S24_BE] = {
  68                 .width = 24, .phys = 32, .le = 0, .signd = 1,
  69                 .silence = {},
  70         },
  71         [SNDRV_PCM_FORMAT_U24_LE] = {
  72                 .width = 24, .phys = 32, .le = 1, .signd = 0,
  73                 .silence = { 0x00, 0x00, 0x80 },
  74         },
  75         [SNDRV_PCM_FORMAT_U24_BE] = {
  76                 .width = 24, .phys = 32, .le = 0, .signd = 0,
  77                 .silence = { 0x00, 0x80, 0x00, 0x00 },
  78         },
  79         [SNDRV_PCM_FORMAT_S32_LE] = {
  80                 .width = 32, .phys = 32, .le = 1, .signd = 1,
  81                 .silence = {},
  82         },
  83         [SNDRV_PCM_FORMAT_S32_BE] = {
  84                 .width = 32, .phys = 32, .le = 0, .signd = 1,
  85                 .silence = {},
  86         },
  87         [SNDRV_PCM_FORMAT_U32_LE] = {
  88                 .width = 32, .phys = 32, .le = 1, .signd = 0,
  89                 .silence = { 0x00, 0x00, 0x00, 0x80 },
  90         },
  91         [SNDRV_PCM_FORMAT_U32_BE] = {
  92                 .width = 32, .phys = 32, .le = 0, .signd = 0,
  93                 .silence = { 0x80, 0x00, 0x00, 0x00 },
  94         },
  95         [SNDRV_PCM_FORMAT_FLOAT_LE] = {
  96                 .width = 32, .phys = 32, .le = 1, .signd = -1,
  97                 .silence = {},
  98         },
  99         [SNDRV_PCM_FORMAT_FLOAT_BE] = {
 100                 .width = 32, .phys = 32, .le = 0, .signd = -1,
 101                 .silence = {},
 102         },
 103         [SNDRV_PCM_FORMAT_FLOAT64_LE] = {
 104                 .width = 64, .phys = 64, .le = 1, .signd = -1,
 105                 .silence = {},
 106         },
 107         [SNDRV_PCM_FORMAT_FLOAT64_BE] = {
 108                 .width = 64, .phys = 64, .le = 0, .signd = -1,
 109                 .silence = {},
 110         },
 111         [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE] = {
 112                 .width = 32, .phys = 32, .le = 1, .signd = -1,
 113                 .silence = {},
 114         },
 115         [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE] = {
 116                 .width = 32, .phys = 32, .le = 0, .signd = -1,
 117                 .silence = {},
 118         },
 119         [SNDRV_PCM_FORMAT_MU_LAW] = {
 120                 .width = 8, .phys = 8, .le = -1, .signd = -1,
 121                 .silence = { 0x7f },
 122         },
 123         [SNDRV_PCM_FORMAT_A_LAW] = {
 124                 .width = 8, .phys = 8, .le = -1, .signd = -1,
 125                 .silence = { 0x55 },
 126         },
 127         [SNDRV_PCM_FORMAT_IMA_ADPCM] = {
 128                 .width = 4, .phys = 4, .le = -1, .signd = -1,
 129                 .silence = {},
 130         },
 131         [SNDRV_PCM_FORMAT_G723_24] = {
 132                 .width = 3, .phys = 3, .le = -1, .signd = -1,
 133                 .silence = {},
 134         },
 135         [SNDRV_PCM_FORMAT_G723_40] = {
 136                 .width = 5, .phys = 5, .le = -1, .signd = -1,
 137                 .silence = {},
 138         },
 139         [SNDRV_PCM_FORMAT_MPEG] = {
 140                 .le = -1, .signd = -1,
 141         },
 142         [SNDRV_PCM_FORMAT_GSM] = {
 143                 .le = -1, .signd = -1,
 144         },
 145         [SNDRV_PCM_FORMAT_SPECIAL] = {
 146                 .le = -1, .signd = -1,
 147         },
 148         [SNDRV_PCM_FORMAT_S24_3LE] = {
 149                 .width = 24, .phys = 24, .le = 1, .signd = 1,
 150                 .silence = {},
 151         },
 152         [SNDRV_PCM_FORMAT_S24_3BE] = {
 153                 .width = 24, .phys = 24, .le = 0, .signd = 1,
 154                 .silence = {},
 155         },
 156         [SNDRV_PCM_FORMAT_U24_3LE] = {
 157                 .width = 24, .phys = 24, .le = 1, .signd = 0,
 158                 .silence = { 0x00, 0x00, 0x80 },
 159         },
 160         [SNDRV_PCM_FORMAT_U24_3BE] = {
 161                 .width = 24, .phys = 24, .le = 0, .signd = 0,
 162                 .silence = { 0x80, 0x00, 0x00 },
 163         },
 164         [SNDRV_PCM_FORMAT_S20_3LE] = {
 165                 .width = 20, .phys = 24, .le = 1, .signd = 1,
 166                 .silence = {},
 167         },
 168         [SNDRV_PCM_FORMAT_S20_3BE] = {
 169                 .width = 20, .phys = 24, .le = 0, .signd = 1,
 170                 .silence = {},
 171         },
 172         [SNDRV_PCM_FORMAT_U20_3LE] = {
 173                 .width = 20, .phys = 24, .le = 1, .signd = 0,
 174                 .silence = { 0x00, 0x00, 0x08 },
 175         },
 176         [SNDRV_PCM_FORMAT_U20_3BE] = {
 177                 .width = 20, .phys = 24, .le = 0, .signd = 0,
 178                 .silence = { 0x08, 0x00, 0x00 },
 179         },
 180         [SNDRV_PCM_FORMAT_S18_3LE] = {
 181                 .width = 18, .phys = 24, .le = 1, .signd = 1,
 182                 .silence = {},
 183         },
 184         [SNDRV_PCM_FORMAT_S18_3BE] = {
 185                 .width = 18, .phys = 24, .le = 0, .signd = 1,
 186                 .silence = {},
 187         },
 188         [SNDRV_PCM_FORMAT_U18_3LE] = {
 189                 .width = 18, .phys = 24, .le = 1, .signd = 0,
 190                 .silence = { 0x00, 0x00, 0x02 },
 191         },
 192         [SNDRV_PCM_FORMAT_U18_3BE] = {
 193                 .width = 18, .phys = 24, .le = 0, .signd = 0,
 194                 .silence = { 0x02, 0x00, 0x00 },
 195         },
 196         [SNDRV_PCM_FORMAT_G723_24_1B] = {
 197                 .width = 3, .phys = 8, .le = -1, .signd = -1,
 198                 .silence = {},
 199         },
 200         [SNDRV_PCM_FORMAT_G723_40_1B] = {
 201                 .width = 5, .phys = 8, .le = -1, .signd = -1,
 202                 .silence = {},
 203         },
 204 };
 205
 206
 207 /**
 208  * snd_pcm_format_signed - Check the PCM format is signed linear
 209  * @format: the format to check
 210  *
 211  * Returns 1 if the given PCM format is signed linear, 0 if unsigned
 212  * linear, and a negative error code for non-linear formats.
 213  */
 214 int snd_pcm_format_signed(snd_pcm_format_t format)
 215 {
 216         int val;
 217         if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
 218                 return -EINVAL;
 219         if ((val = pcm_formats[format].signd) < 0)
 220                 return -EINVAL;
 221         return val;
 222 }
 223
 224 EXPORT_SYMBOL(snd_pcm_format_signed);
 225
 226 /**
 227  * snd_pcm_format_unsigned - Check the PCM format is unsigned linear
 228  * @format: the format to check
 229  *
 230  * Returns 1 if the given PCM format is unsigned linear, 0 if signed
 231  * linear, and a negative error code for non-linear formats.
 232  */
 233 int snd_pcm_format_unsigned(snd_pcm_format_t format)
 234 {
 235         int val;
 236
 237         val = snd_pcm_format_signed(format);
 238         if (val < 0)
 239                 return val;
 240         return !val;
 241 }
 242
 243 EXPORT_SYMBOL(snd_pcm_format_unsigned);
 244
 245 /**
 246  * snd_pcm_format_linear - Check the PCM format is linear
 247  * @format: the format to check
 248  *
 249  * Returns 1 if the given PCM format is linear, 0 if not.
 250  */
 251 int snd_pcm_format_linear(snd_pcm_format_t format)
 252 {
 253         return snd_pcm_format_signed(format) >= 0;
 254 }
 255
 256 EXPORT_SYMBOL(snd_pcm_format_linear);
 257
 258 /**
 259  * snd_pcm_format_little_endian - Check the PCM format is little-endian
 260  * @format: the format to check
 261  *
 262  * Returns 1 if the given PCM format is little-endian, 0 if
 263  * big-endian, or a negative error code if endian not specified.
 264  */
 265 int snd_pcm_format_little_endian(snd_pcm_format_t format)
 266 {
 267         int val;
 268         if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
 269                 return -EINVAL;
 270         if ((val = pcm_formats[format].le) < 0)
 271                 return -EINVAL;
 272         return val;
 273 }
 274
 275 EXPORT_SYMBOL(snd_pcm_format_little_endian);
 276
 277 /**
 278  * snd_pcm_format_big_endian - Check the PCM format is big-endian
 279  * @format: the format to check
 280  *
 281  * Returns 1 if the given PCM format is big-endian, 0 if
 282  * little-endian, or a negative error code if endian not specified.
 283  */
 284 int snd_pcm_format_big_endian(snd_pcm_format_t format)
 285 {
 286         int val;
 287
 288         val = snd_pcm_format_little_endian(format);
 289         if (val < 0)
 290                 return val;
 291         return !val;
 292 }
 293
 294 EXPORT_SYMBOL(snd_pcm_format_big_endian);
 295
 296 /**
 297  * snd_pcm_format_width - return the bit-width of the format
 298  * @format: the format to check
 299  *
 300  * Returns the bit-width of the format, or a negative error code
 301  * if unknown format.
 302  */
 303 int snd_pcm_format_width(snd_pcm_format_t format)
 304 {
 305         int val;
 306         if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
 307                 return -EINVAL;
 308         if ((val = pcm_formats[format].width) == 0)
 309                 return -EINVAL;
 310         return val;
 311 }
 312
 313 EXPORT_SYMBOL(snd_pcm_format_width);
 314
 315 /**
 316  * snd_pcm_format_physical_width - return the physical bit-width of the format
 317  * @format: the format to check
 318  *
 319  * Returns the physical bit-width of the format, or a negative error code
 320  * if unknown format.
 321  */
 322 int snd_pcm_format_physical_width(snd_pcm_format_t format)
 323 {
 324         int val;
 325         if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
 326                 return -EINVAL;
 327         if ((val = pcm_formats[format].phys) == 0)
 328                 return -EINVAL;
 329         return val;
 330 }
 331
 332 EXPORT_SYMBOL(snd_pcm_format_physical_width);
 333
 334 /**
 335  * snd_pcm_format_size - return the byte size of samples on the given format
 336  * @format: the format to check
 337  * @samples: sampling rate
 338  *
 339  * Returns the byte size of the given samples for the format, or a
 340  * negative error code if unknown format.
 341  */
 342 ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples)
 343 {
 344         int phys_width = snd_pcm_format_physical_width(format);
 345         if (phys_width < 0)
 346                 return -EINVAL;
 347         return samples * phys_width / 8;
 348 }
 349
 350 EXPORT_SYMBOL(snd_pcm_format_size);
 351
 352 /**
 353  * snd_pcm_format_silence_64 - return the silent data in 8 bytes array
 354  * @format: the format to check
 355  *
 356  * Returns the format pattern to fill or NULL if error.
 357  */
 358 const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format)
 359 {
 360         if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
 361                 return NULL;
 362         if (! pcm_formats[format].phys)
 363                 return NULL;
 364         return pcm_formats[format].silence;
 365 }
 366
 367 EXPORT_SYMBOL(snd_pcm_format_silence_64);
 368
 369 /**
 370  * snd_pcm_format_set_silence - set the silence data on the buffer
 371  * @format: the PCM format
 372  * @data: the buffer pointer
 373  * @samples: the number of samples to set silence
 374  *
 375  * Sets the silence data on the buffer for the given samples.
 376  *
 377  * Returns zero if successful, or a negative error code on failure.
 378  */
 379 int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples)
 380 {
 381         int width;
 382         unsigned char *dst, *pat;
 383
 384         if (format < 0 || format > SNDRV_PCM_FORMAT_LAST)
 385                 return -EINVAL;
 386         if (samples == 0)
 387                 return 0;
 388         width = pcm_formats[format].phys; /* physical width */
 389         pat = pcm_formats[format].silence;
 390         if (! width)
 391                 return -EINVAL;
 392         /* signed or 1 byte data */
 393         if (pcm_formats[format].signd == 1 || width <= 8) {
 394                 unsigned int bytes = samples * width / 8;
 395                 memset(data, *pat, bytes);
 396                 return 0;
 397         }
 398         /* non-zero samples, fill using a loop */
 399         width /= 8;
 400         dst = data;
 401         /* a bit optimization for constant width */
 402         switch (width) {
 403         case 2:
 404                 while (samples--) {
 405                         memcpy(dst, pat, 2);
 406                         dst += 2;
 407                 }
 408                 break;
 409         case 3:
 410                 while (samples--) {
 411                         memcpy(dst, pat, 3);
 412                         dst += 3;
 413                 }
 414                 break;
 415         case 4:
 416                 while (samples--) {
 417                         memcpy(dst, pat, 4);
 418                         dst += 4;
 419                 }
 420                 break;
 421         case 8:
 422                 while (samples--) {
 423                         memcpy(dst, pat, 8);
 424                         dst += 8;
 425                 }
 426                 break;
 427         }
 428         return 0;
 429 }
 430
 431 EXPORT_SYMBOL(snd_pcm_format_set_silence);
 432
 433 /**
 434  * snd_pcm_limit_hw_rates - determine rate_min/rate_max fields
 435  * @runtime: the runtime instance
 436  *
 437  * Determines the rate_min and rate_max fields from the rates bits of
 438  * the given runtime->hw.
 439  *
 440  * Returns zero if successful.
 441  */
 442 int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime)
 443 {
 444         int i;
 445         for (i = 0; i < (int)snd_pcm_known_rates.count; i++) {
 446                 if (runtime->hw.rates & (1 << i)) {
 447                         runtime->hw.rate_min = snd_pcm_known_rates.list[i];
 448                         break;
 449                 }
 450         }
 451         for (i = (int)snd_pcm_known_rates.count - 1; i >= 0; i--) {
 452                 if (runtime->hw.rates & (1 << i)) {
 453                         runtime->hw.rate_max = snd_pcm_known_rates.list[i];
 454                         break;
 455                 }
 456         }
 457         return 0;
 458 }
 459
 460 EXPORT_SYMBOL(snd_pcm_limit_hw_rates);
 461
 462 /**
 463  * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit
 464  * @rate: the sample rate to convert
 465  *
 466  * Returns the SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or
 467  * SNDRV_PCM_RATE_KNOT for an unknown rate.
 468  */
 469 unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate)
 470 {
 471         unsigned int i;
 472
 473         for (i = 0; i < snd_pcm_known_rates.count; i++)
 474                 if (snd_pcm_known_rates.list[i] == rate)
 475                         return 1u << i;
 476         return SNDRV_PCM_RATE_KNOT;
 477 }
 478 EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit);