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 = { 0x69 }, 146 }, 147 [SNDRV_PCM_FORMAT_DSD_U16_LE] = { 148 .width = 16, .phys = 16, .le = 1, .signd = 0, 149 .silence = { 0x69, 0x69 }, 150 }, 151 [SNDRV_PCM_FORMAT_DSD_U32_LE] = { 152 .width = 32, .phys = 32, .le = 1, .signd = 0, 153 .silence = { 0x69, 0x69, 0x69, 0x69 }, 154 }, 155 /* FIXME: the following three formats are not defined properly yet */ 156 [SNDRV_PCM_FORMAT_MPEG] = { 157 .le = -1, .signd = -1, 158 }, 159 [SNDRV_PCM_FORMAT_GSM] = { 160 .le = -1, .signd = -1, 161 }, 162 [SNDRV_PCM_FORMAT_SPECIAL] = { 163 .le = -1, .signd = -1, 164 }, 165 [SNDRV_PCM_FORMAT_S24_3LE] = { 166 .width = 24, .phys = 24, .le = 1, .signd = 1, 167 .silence = {}, 168 }, 169 [SNDRV_PCM_FORMAT_S24_3BE] = { 170 .width = 24, .phys = 24, .le = 0, .signd = 1, 171 .silence = {}, 172 }, 173 [SNDRV_PCM_FORMAT_U24_3LE] = { 174 .width = 24, .phys = 24, .le = 1, .signd = 0, 175 .silence = { 0x00, 0x00, 0x80 }, 176 }, 177 [SNDRV_PCM_FORMAT_U24_3BE] = { 178 .width = 24, .phys = 24, .le = 0, .signd = 0, 179 .silence = { 0x80, 0x00, 0x00 }, 180 }, 181 [SNDRV_PCM_FORMAT_S20_3LE] = { 182 .width = 20, .phys = 24, .le = 1, .signd = 1, 183 .silence = {}, 184 }, 185 [SNDRV_PCM_FORMAT_S20_3BE] = { 186 .width = 20, .phys = 24, .le = 0, .signd = 1, 187 .silence = {}, 188 }, 189 [SNDRV_PCM_FORMAT_U20_3LE] = { 190 .width = 20, .phys = 24, .le = 1, .signd = 0, 191 .silence = { 0x00, 0x00, 0x08 }, 192 }, 193 [SNDRV_PCM_FORMAT_U20_3BE] = { 194 .width = 20, .phys = 24, .le = 0, .signd = 0, 195 .silence = { 0x08, 0x00, 0x00 }, 196 }, 197 [SNDRV_PCM_FORMAT_S18_3LE] = { 198 .width = 18, .phys = 24, .le = 1, .signd = 1, 199 .silence = {}, 200 }, 201 [SNDRV_PCM_FORMAT_S18_3BE] = { 202 .width = 18, .phys = 24, .le = 0, .signd = 1, 203 .silence = {}, 204 }, 205 [SNDRV_PCM_FORMAT_U18_3LE] = { 206 .width = 18, .phys = 24, .le = 1, .signd = 0, 207 .silence = { 0x00, 0x00, 0x02 }, 208 }, 209 [SNDRV_PCM_FORMAT_U18_3BE] = { 210 .width = 18, .phys = 24, .le = 0, .signd = 0, 211 .silence = { 0x02, 0x00, 0x00 }, 212 }, 213 [SNDRV_PCM_FORMAT_G723_24_1B] = { 214 .width = 3, .phys = 8, .le = -1, .signd = -1, 215 .silence = {}, 216 }, 217 [SNDRV_PCM_FORMAT_G723_40_1B] = { 218 .width = 5, .phys = 8, .le = -1, .signd = -1, 219 .silence = {}, 220 }, 221 }; 222 223 224 /** 225 * snd_pcm_format_signed - Check the PCM format is signed linear 226 * @format: the format to check 227 * 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. 230 */ 231 int snd_pcm_format_signed(snd_pcm_format_t format) 232 { 233 int val; 234 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) 235 return -EINVAL; 236 if ((val = pcm_formats[(INT)format].signd) < 0) 237 return -EINVAL; 238 return val; 239 } 240 241 EXPORT_SYMBOL(snd_pcm_format_signed); 242 243 /** 244 * snd_pcm_format_unsigned - Check the PCM format is unsigned linear 245 * @format: the format to check 246 * 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. 249 */ 250 int snd_pcm_format_unsigned(snd_pcm_format_t format) 251 { 252 int val; 253 254 val = snd_pcm_format_signed(format); 255 if (val < 0) 256 return val; 257 return !val; 258 } 259 260 EXPORT_SYMBOL(snd_pcm_format_unsigned); 261 262 /** 263 * snd_pcm_format_linear - Check the PCM format is linear 264 * @format: the format to check 265 * 266 * Return: 1 if the given PCM format is linear, 0 if not. 267 */ 268 int snd_pcm_format_linear(snd_pcm_format_t format) 269 { 270 return snd_pcm_format_signed(format) >= 0; 271 } 272 273 EXPORT_SYMBOL(snd_pcm_format_linear); 274 275 /** 276 * snd_pcm_format_little_endian - Check the PCM format is little-endian 277 * @format: the format to check 278 * 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. 281 */ 282 int snd_pcm_format_little_endian(snd_pcm_format_t format) 283 { 284 int val; 285 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) 286 return -EINVAL; 287 if ((val = pcm_formats[(INT)format].le) < 0) 288 return -EINVAL; 289 return val; 290 } 291 292 EXPORT_SYMBOL(snd_pcm_format_little_endian); 293 294 /** 295 * snd_pcm_format_big_endian - Check the PCM format is big-endian 296 * @format: the format to check 297 * 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. 300 */ 301 int snd_pcm_format_big_endian(snd_pcm_format_t format) 302 { 303 int val; 304 305 val = snd_pcm_format_little_endian(format); 306 if (val < 0) 307 return val; 308 return !val; 309 } 310 311 EXPORT_SYMBOL(snd_pcm_format_big_endian); 312 313 /** 314 * snd_pcm_format_width - return the bit-width of the format 315 * @format: the format to check 316 * 317 * Return: The bit-width of the format, or a negative error code 318 * if unknown format. 319 */ 320 int snd_pcm_format_width(snd_pcm_format_t format) 321 { 322 int val; 323 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) 324 return -EINVAL; 325 if ((val = pcm_formats[(INT)format].width) == 0) 326 return -EINVAL; 327 return val; 328 } 329 330 EXPORT_SYMBOL(snd_pcm_format_width); 331 332 /** 333 * snd_pcm_format_physical_width - return the physical bit-width of the format 334 * @format: the format to check 335 * 336 * Return: The physical bit-width of the format, or a negative error code 337 * if unknown format. 338 */ 339 int snd_pcm_format_physical_width(snd_pcm_format_t format) 340 { 341 int val; 342 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) 343 return -EINVAL; 344 if ((val = pcm_formats[(INT)format].phys) == 0) 345 return -EINVAL; 346 return val; 347 } 348 349 EXPORT_SYMBOL(snd_pcm_format_physical_width); 350 351 /** 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 355 * 356 * Return: The byte size of the given samples for the format, or a 357 * negative error code if unknown format. 358 */ 359 ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples) 360 { 361 int phys_width = snd_pcm_format_physical_width(format); 362 if (phys_width < 0) 363 return -EINVAL; 364 return samples * phys_width / 8; 365 } 366 367 EXPORT_SYMBOL(snd_pcm_format_size); 368 369 /** 370 * snd_pcm_format_silence_64 - return the silent data in 8 bytes array 371 * @format: the format to check 372 * 373 * Return: The format pattern to fill or %NULL if error. 374 */ 375 const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format) 376 { 377 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) 378 return NULL; 379 if (! pcm_formats[(INT)format].phys) 380 return NULL; 381 return pcm_formats[(INT)format].silence; 382 } 383 384 EXPORT_SYMBOL(snd_pcm_format_silence_64); 385 386 /** 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 391 * 392 * Sets the silence data on the buffer for the given samples. 393 * 394 * Return: Zero if successful, or a negative error code on failure. 395 */ 396 int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples) 397 { 398 int width; 399 unsigned char *dst, *pat; 400 401 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) 402 return -EINVAL; 403 if (samples == 0) 404 return 0; 405 width = pcm_formats[(INT)format].phys; /* physical width */ 406 pat = pcm_formats[(INT)format].silence; 407 if (! width) 408 return -EINVAL; 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); 413 return 0; 414 } 415 /* non-zero samples, fill using a loop */ 416 width /= 8; 417 dst = data; 418 #if 0 419 while (samples--) { 420 memcpy(dst, pat, width); 421 dst += width; 422 } 423 #else 424 /* a bit optimization for constant width */ 425 switch (width) { 426 case 2: 427 while (samples--) { 428 memcpy(dst, pat, 2); 429 dst += 2; 430 } 431 break; 432 case 3: 433 while (samples--) { 434 memcpy(dst, pat, 3); 435 dst += 3; 436 } 437 break; 438 case 4: 439 while (samples--) { 440 memcpy(dst, pat, 4); 441 dst += 4; 442 } 443 break; 444 case 8: 445 while (samples--) { 446 memcpy(dst, pat, 8); 447 dst += 8; 448 } 449 break; 450 } 451 #endif 452 return 0; 453 } 454 455 EXPORT_SYMBOL(snd_pcm_format_set_silence); 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 * Return: Zero if successful. 465 */ 466 int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime) 467 { 468 int i; 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]; 472 break; 473 } 474 } 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]; 478 break; 479 } 480 } 481 return 0; 482 } 483 484 EXPORT_SYMBOL(snd_pcm_limit_hw_rates); 485 486 /** 487 * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit 488 * @rate: the sample rate to convert 489 * 490 * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or 491 * SNDRV_PCM_RATE_KNOT for an unknown rate. 492 */ 493 unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate) 494 { 495 unsigned int i; 496 497 for (i = 0; i < snd_pcm_known_rates.count; i++) 498 if (snd_pcm_known_rates.list[i] == rate) 499 return 1u << i; 500 return SNDRV_PCM_RATE_KNOT; 501 } 502 EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit); 503 504 /** 505 * snd_pcm_rate_bit_to_rate - converts SNDRV_PCM_RATE_xxx bit to sample rate 506 * @rate_bit: the rate bit to convert 507 * 508 * Return: The sample rate that corresponds to the given SNDRV_PCM_RATE_xxx flag 509 * or 0 for an unknown rate bit. 510 */ 511 unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit) 512 { 513 unsigned int i; 514 515 for (i = 0; i < snd_pcm_known_rates.count; i++) 516 if ((1u << i) == rate_bit) 517 return snd_pcm_known_rates.list[i]; 518 return 0; 519 } 520 EXPORT_SYMBOL(snd_pcm_rate_bit_to_rate); 521 522 static unsigned int snd_pcm_rate_mask_sanitize(unsigned int rates) 523 { 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; 528 return rates; 529 } 530 531 /** 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 535 * 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. 539 * 540 * Return: A rate mask containing the rates that are supported by both rates_a 541 * and rates_b. 542 */ 543 unsigned int snd_pcm_rate_mask_intersect(unsigned int rates_a, 544 unsigned int rates_b) 545 { 546 rates_a = snd_pcm_rate_mask_sanitize(rates_a); 547 rates_b = snd_pcm_rate_mask_sanitize(rates_b); 548 549 if (rates_a & SNDRV_PCM_RATE_CONTINUOUS) 550 return rates_b; 551 else if (rates_b & SNDRV_PCM_RATE_CONTINUOUS) 552 return rates_a; 553 else if (rates_a & SNDRV_PCM_RATE_KNOT) 554 return rates_b; 555 else if (rates_b & SNDRV_PCM_RATE_KNOT) 556 return rates_a; 557 return rates_a & rates_b; 558 } 559 EXPORT_SYMBOL_GPL(snd_pcm_rate_mask_intersect); 560