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 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 is 32 * unsigned on some architectures! 33 */ 34 struct 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 int 44 45 static const struct pcm_format_data pcm_formats[(INT)SNDRV_PCM_FORMAT_LAST+1] = { 46 [SNDRV_PCM_FORMAT_S8] = { 47 .width = 8, .phys = 8, .le = -1, .signd = 1, 48 .silence = {}, 49 }, 50 [SNDRV_PCM_FORMAT_U8] = { 51 .width = 8, .phys = 8, .le = -1, .signd = 0, 52 .silence = { 0x80 }, 53 }, 54 [SNDRV_PCM_FORMAT_S16_LE] = { 55 .width = 16, .phys = 16, .le = 1, .signd = 1, 56 .silence = {}, 57 }, 58 [SNDRV_PCM_FORMAT_S16_BE] = { 59 .width = 16, .phys = 16, .le = 0, .signd = 1, 60 .silence = {}, 61 }, 62 [SNDRV_PCM_FORMAT_U16_LE] = { 63 .width = 16, .phys = 16, .le = 1, .signd = 0, 64 .silence = { 0x00, 0x80 }, 65 }, 66 [SNDRV_PCM_FORMAT_U16_BE] = { 67 .width = 16, .phys = 16, .le = 0, .signd = 0, 68 .silence = { 0x80, 0x00 }, 69 }, 70 [SNDRV_PCM_FORMAT_S24_LE] = { 71 .width = 24, .phys = 32, .le = 1, .signd = 1, 72 .silence = {}, 73 }, 74 [SNDRV_PCM_FORMAT_S24_BE] = { 75 .width = 24, .phys = 32, .le = 0, .signd = 1, 76 .silence = {}, 77 }, 78 [SNDRV_PCM_FORMAT_U24_LE] = { 79 .width = 24, .phys = 32, .le = 1, .signd = 0, 80 .silence = { 0x00, 0x00, 0x80 }, 81 }, 82 [SNDRV_PCM_FORMAT_U24_BE] = { 83 .width = 24, .phys = 32, .le = 0, .signd = 0, 84 .silence = { 0x00, 0x80, 0x00, 0x00 }, 85 }, 86 [SNDRV_PCM_FORMAT_S32_LE] = { 87 .width = 32, .phys = 32, .le = 1, .signd = 1, 88 .silence = {}, 89 }, 90 [SNDRV_PCM_FORMAT_S32_BE] = { 91 .width = 32, .phys = 32, .le = 0, .signd = 1, 92 .silence = {}, 93 }, 94 [SNDRV_PCM_FORMAT_U32_LE] = { 95 .width = 32, .phys = 32, .le = 1, .signd = 0, 96 .silence = { 0x00, 0x00, 0x00, 0x80 }, 97 }, 98 [SNDRV_PCM_FORMAT_U32_BE] = { 99 .width = 32, .phys = 32, .le = 0, .signd = 0, 100 .silence = { 0x80, 0x00, 0x00, 0x00 }, 101 }, 102 [SNDRV_PCM_FORMAT_FLOAT_LE] = { 103 .width = 32, .phys = 32, .le = 1, .signd = -1, 104 .silence = {}, 105 }, 106 [SNDRV_PCM_FORMAT_FLOAT_BE] = { 107 .width = 32, .phys = 32, .le = 0, .signd = -1, 108 .silence = {}, 109 }, 110 [SNDRV_PCM_FORMAT_FLOAT64_LE] = { 111 .width = 64, .phys = 64, .le = 1, .signd = -1, 112 .silence = {}, 113 }, 114 [SNDRV_PCM_FORMAT_FLOAT64_BE] = { 115 .width = 64, .phys = 64, .le = 0, .signd = -1, 116 .silence = {}, 117 }, 118 [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE] = { 119 .width = 32, .phys = 32, .le = 1, .signd = -1, 120 .silence = {}, 121 }, 122 [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE] = { 123 .width = 32, .phys = 32, .le = 0, .signd = -1, 124 .silence = {}, 125 }, 126 [SNDRV_PCM_FORMAT_MU_LAW] = { 127 .width = 8, .phys = 8, .le = -1, .signd = -1, 128 .silence = { 0x7f }, 129 }, 130 [SNDRV_PCM_FORMAT_A_LAW] = { 131 .width = 8, .phys = 8, .le = -1, .signd = -1, 132 .silence = { 0x55 }, 133 }, 134 [SNDRV_PCM_FORMAT_IMA_ADPCM] = { 135 .width = 4, .phys = 4, .le = -1, .signd = -1, 136 .silence = {}, 137 }, 138 [SNDRV_PCM_FORMAT_G723_24] = { 139 .width = 3, .phys = 3, .le = -1, .signd = -1, 140 .silence = {}, 141 }, 142 [SNDRV_PCM_FORMAT_G723_40] = { 143 .width = 5, .phys = 5, .le = -1, .signd = -1, 144 .silence = {}, 145 }, 146 [SNDRV_PCM_FORMAT_DSD_U8] = { 147 .width = 8, .phys = 8, .le = 1, .signd = 0, 148 .silence = { 0x69 }, 149 }, 150 [SNDRV_PCM_FORMAT_DSD_U16_LE] = { 151 .width = 16, .phys = 16, .le = 1, .signd = 0, 152 .silence = { 0x69, 0x69 }, 153 }, 154 [SNDRV_PCM_FORMAT_DSD_U32_LE] = { 155 .width = 32, .phys = 32, .le = 1, .signd = 0, 156 .silence = { 0x69, 0x69, 0x69, 0x69 }, 157 }, 158 [SNDRV_PCM_FORMAT_DSD_U16_BE] = { 159 .width = 16, .phys = 16, .le = 0, .signd = 0, 160 .silence = { 0x69, 0x69 }, 161 }, 162 [SNDRV_PCM_FORMAT_DSD_U32_BE] = { 163 .width = 32, .phys = 32, .le = 0, .signd = 0, 164 .silence = { 0x69, 0x69, 0x69, 0x69 }, 165 }, 166 /* FIXME: the following two formats are not defined properly yet */ 167 [SNDRV_PCM_FORMAT_MPEG] = { 168 .le = -1, .signd = -1, 169 }, 170 [SNDRV_PCM_FORMAT_GSM] = { 171 .le = -1, .signd = -1, 172 }, 173 [SNDRV_PCM_FORMAT_S20_LE] = { 174 .width = 20, .phys = 32, .le = 1, .signd = 1, 175 .silence = {}, 176 }, 177 [SNDRV_PCM_FORMAT_S20_BE] = { 178 .width = 20, .phys = 32, .le = 0, .signd = 1, 179 .silence = {}, 180 }, 181 [SNDRV_PCM_FORMAT_U20_LE] = { 182 .width = 20, .phys = 32, .le = 1, .signd = 0, 183 .silence = { 0x00, 0x00, 0x08, 0x00 }, 184 }, 185 [SNDRV_PCM_FORMAT_U20_BE] = { 186 .width = 20, .phys = 32, .le = 0, .signd = 0, 187 .silence = { 0x00, 0x08, 0x00, 0x00 }, 188 }, 189 /* FIXME: the following format is not defined properly yet */ 190 [SNDRV_PCM_FORMAT_SPECIAL] = { 191 .le = -1, .signd = -1, 192 }, 193 [SNDRV_PCM_FORMAT_S24_3LE] = { 194 .width = 24, .phys = 24, .le = 1, .signd = 1, 195 .silence = {}, 196 }, 197 [SNDRV_PCM_FORMAT_S24_3BE] = { 198 .width = 24, .phys = 24, .le = 0, .signd = 1, 199 .silence = {}, 200 }, 201 [SNDRV_PCM_FORMAT_U24_3LE] = { 202 .width = 24, .phys = 24, .le = 1, .signd = 0, 203 .silence = { 0x00, 0x00, 0x80 }, 204 }, 205 [SNDRV_PCM_FORMAT_U24_3BE] = { 206 .width = 24, .phys = 24, .le = 0, .signd = 0, 207 .silence = { 0x80, 0x00, 0x00 }, 208 }, 209 [SNDRV_PCM_FORMAT_S20_3LE] = { 210 .width = 20, .phys = 24, .le = 1, .signd = 1, 211 .silence = {}, 212 }, 213 [SNDRV_PCM_FORMAT_S20_3BE] = { 214 .width = 20, .phys = 24, .le = 0, .signd = 1, 215 .silence = {}, 216 }, 217 [SNDRV_PCM_FORMAT_U20_3LE] = { 218 .width = 20, .phys = 24, .le = 1, .signd = 0, 219 .silence = { 0x00, 0x00, 0x08 }, 220 }, 221 [SNDRV_PCM_FORMAT_U20_3BE] = { 222 .width = 20, .phys = 24, .le = 0, .signd = 0, 223 .silence = { 0x08, 0x00, 0x00 }, 224 }, 225 [SNDRV_PCM_FORMAT_S18_3LE] = { 226 .width = 18, .phys = 24, .le = 1, .signd = 1, 227 .silence = {}, 228 }, 229 [SNDRV_PCM_FORMAT_S18_3BE] = { 230 .width = 18, .phys = 24, .le = 0, .signd = 1, 231 .silence = {}, 232 }, 233 [SNDRV_PCM_FORMAT_U18_3LE] = { 234 .width = 18, .phys = 24, .le = 1, .signd = 0, 235 .silence = { 0x00, 0x00, 0x02 }, 236 }, 237 [SNDRV_PCM_FORMAT_U18_3BE] = { 238 .width = 18, .phys = 24, .le = 0, .signd = 0, 239 .silence = { 0x02, 0x00, 0x00 }, 240 }, 241 [SNDRV_PCM_FORMAT_G723_24_1B] = { 242 .width = 3, .phys = 8, .le = -1, .signd = -1, 243 .silence = {}, 244 }, 245 [SNDRV_PCM_FORMAT_G723_40_1B] = { 246 .width = 5, .phys = 8, .le = -1, .signd = -1, 247 .silence = {}, 248 }, 249 }; 250 251 252 /** 253 * snd_pcm_format_signed - Check the PCM format is signed linear 254 * @format: the format to check 255 * 256 * Return: 1 if the given PCM format is signed linear, 0 if unsigned 257 * linear, and a negative error code for non-linear formats. 258 */ 259 int snd_pcm_format_signed(snd_pcm_format_t format) 260 { 261 int val; 262 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) 263 return -EINVAL; 264 if ((val = pcm_formats[(INT)format].signd) < 0) 265 return -EINVAL; 266 return val; 267 } 268 EXPORT_SYMBOL(snd_pcm_format_signed); 269 270 /** 271 * snd_pcm_format_unsigned - Check the PCM format is unsigned linear 272 * @format: the format to check 273 * 274 * Return: 1 if the given PCM format is unsigned linear, 0 if signed 275 * linear, and a negative error code for non-linear formats. 276 */ 277 int snd_pcm_format_unsigned(snd_pcm_format_t format) 278 { 279 int val; 280 281 val = snd_pcm_format_signed(format); 282 if (val < 0) 283 return val; 284 return !val; 285 } 286 EXPORT_SYMBOL(snd_pcm_format_unsigned); 287 288 /** 289 * snd_pcm_format_linear - Check the PCM format is linear 290 * @format: the format to check 291 * 292 * Return: 1 if the given PCM format is linear, 0 if not. 293 */ 294 int snd_pcm_format_linear(snd_pcm_format_t format) 295 { 296 return snd_pcm_format_signed(format) >= 0; 297 } 298 EXPORT_SYMBOL(snd_pcm_format_linear); 299 300 /** 301 * snd_pcm_format_little_endian - Check the PCM format is little-endian 302 * @format: the format to check 303 * 304 * Return: 1 if the given PCM format is little-endian, 0 if 305 * big-endian, or a negative error code if endian not specified. 306 */ 307 int snd_pcm_format_little_endian(snd_pcm_format_t format) 308 { 309 int val; 310 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) 311 return -EINVAL; 312 if ((val = pcm_formats[(INT)format].le) < 0) 313 return -EINVAL; 314 return val; 315 } 316 EXPORT_SYMBOL(snd_pcm_format_little_endian); 317 318 /** 319 * snd_pcm_format_big_endian - Check the PCM format is big-endian 320 * @format: the format to check 321 * 322 * Return: 1 if the given PCM format is big-endian, 0 if 323 * little-endian, or a negative error code if endian not specified. 324 */ 325 int snd_pcm_format_big_endian(snd_pcm_format_t format) 326 { 327 int val; 328 329 val = snd_pcm_format_little_endian(format); 330 if (val < 0) 331 return val; 332 return !val; 333 } 334 EXPORT_SYMBOL(snd_pcm_format_big_endian); 335 336 /** 337 * snd_pcm_format_width - return the bit-width of the format 338 * @format: the format to check 339 * 340 * Return: The bit-width of the format, or a negative error code 341 * if unknown format. 342 */ 343 int snd_pcm_format_width(snd_pcm_format_t format) 344 { 345 int val; 346 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) 347 return -EINVAL; 348 if ((val = pcm_formats[(INT)format].width) == 0) 349 return -EINVAL; 350 return val; 351 } 352 EXPORT_SYMBOL(snd_pcm_format_width); 353 354 /** 355 * snd_pcm_format_physical_width - return the physical bit-width of the format 356 * @format: the format to check 357 * 358 * Return: The physical bit-width of the format, or a negative error code 359 * if unknown format. 360 */ 361 int snd_pcm_format_physical_width(snd_pcm_format_t format) 362 { 363 int val; 364 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) 365 return -EINVAL; 366 if ((val = pcm_formats[(INT)format].phys) == 0) 367 return -EINVAL; 368 return val; 369 } 370 EXPORT_SYMBOL(snd_pcm_format_physical_width); 371 372 /** 373 * snd_pcm_format_size - return the byte size of samples on the given format 374 * @format: the format to check 375 * @samples: sampling rate 376 * 377 * Return: The byte size of the given samples for the format, or a 378 * negative error code if unknown format. 379 */ 380 ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples) 381 { 382 int phys_width = snd_pcm_format_physical_width(format); 383 if (phys_width < 0) 384 return -EINVAL; 385 return samples * phys_width / 8; 386 } 387 EXPORT_SYMBOL(snd_pcm_format_size); 388 389 /** 390 * snd_pcm_format_silence_64 - return the silent data in 8 bytes array 391 * @format: the format to check 392 * 393 * Return: The format pattern to fill or %NULL if error. 394 */ 395 const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format) 396 { 397 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) 398 return NULL; 399 if (! pcm_formats[(INT)format].phys) 400 return NULL; 401 return pcm_formats[(INT)format].silence; 402 } 403 EXPORT_SYMBOL(snd_pcm_format_silence_64); 404 405 /** 406 * snd_pcm_format_set_silence - set the silence data on the buffer 407 * @format: the PCM format 408 * @data: the buffer pointer 409 * @samples: the number of samples to set silence 410 * 411 * Sets the silence data on the buffer for the given samples. 412 * 413 * Return: Zero if successful, or a negative error code on failure. 414 */ 415 int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples) 416 { 417 int width; 418 unsigned char *dst; 419 const unsigned char *pat; 420 421 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) 422 return -EINVAL; 423 if (samples == 0) 424 return 0; 425 width = pcm_formats[(INT)format].phys; /* physical width */ 426 pat = pcm_formats[(INT)format].silence; 427 if (! width) 428 return -EINVAL; 429 /* signed or 1 byte data */ 430 if (pcm_formats[(INT)format].signd == 1 || width <= 8) { 431 unsigned int bytes = samples * width / 8; 432 memset(data, *pat, bytes); 433 return 0; 434 } 435 /* non-zero samples, fill using a loop */ 436 width /= 8; 437 dst = data; 438 #if 0 439 while (samples--) { 440 memcpy(dst, pat, width); 441 dst += width; 442 } 443 #else 444 /* a bit optimization for constant width */ 445 switch (width) { 446 case 2: 447 while (samples--) { 448 memcpy(dst, pat, 2); 449 dst += 2; 450 } 451 break; 452 case 3: 453 while (samples--) { 454 memcpy(dst, pat, 3); 455 dst += 3; 456 } 457 break; 458 case 4: 459 while (samples--) { 460 memcpy(dst, pat, 4); 461 dst += 4; 462 } 463 break; 464 case 8: 465 while (samples--) { 466 memcpy(dst, pat, 8); 467 dst += 8; 468 } 469 break; 470 } 471 #endif 472 return 0; 473 } 474 EXPORT_SYMBOL(snd_pcm_format_set_silence); 475 476 /** 477 * snd_pcm_limit_hw_rates - determine rate_min/rate_max fields 478 * @runtime: the runtime instance 479 * 480 * Determines the rate_min and rate_max fields from the rates bits of 481 * the given runtime->hw. 482 * 483 * Return: Zero if successful. 484 */ 485 int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime) 486 { 487 int i; 488 for (i = 0; i < (int)snd_pcm_known_rates.count; i++) { 489 if (runtime->hw.rates & (1 << i)) { 490 runtime->hw.rate_min = snd_pcm_known_rates.list[i]; 491 break; 492 } 493 } 494 for (i = (int)snd_pcm_known_rates.count - 1; i >= 0; i--) { 495 if (runtime->hw.rates & (1 << i)) { 496 runtime->hw.rate_max = snd_pcm_known_rates.list[i]; 497 break; 498 } 499 } 500 return 0; 501 } 502 EXPORT_SYMBOL(snd_pcm_limit_hw_rates); 503 504 /** 505 * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit 506 * @rate: the sample rate to convert 507 * 508 * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or 509 * SNDRV_PCM_RATE_KNOT for an unknown rate. 510 */ 511 unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate) 512 { 513 unsigned int i; 514 515 for (i = 0; i < snd_pcm_known_rates.count; i++) 516 if (snd_pcm_known_rates.list[i] == rate) 517 return 1u << i; 518 return SNDRV_PCM_RATE_KNOT; 519 } 520 EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit); 521 522 /** 523 * snd_pcm_rate_bit_to_rate - converts SNDRV_PCM_RATE_xxx bit to sample rate 524 * @rate_bit: the rate bit to convert 525 * 526 * Return: The sample rate that corresponds to the given SNDRV_PCM_RATE_xxx flag 527 * or 0 for an unknown rate bit. 528 */ 529 unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit) 530 { 531 unsigned int i; 532 533 for (i = 0; i < snd_pcm_known_rates.count; i++) 534 if ((1u << i) == rate_bit) 535 return snd_pcm_known_rates.list[i]; 536 return 0; 537 } 538 EXPORT_SYMBOL(snd_pcm_rate_bit_to_rate); 539 540 static unsigned int snd_pcm_rate_mask_sanitize(unsigned int rates) 541 { 542 if (rates & SNDRV_PCM_RATE_CONTINUOUS) 543 return SNDRV_PCM_RATE_CONTINUOUS; 544 else if (rates & SNDRV_PCM_RATE_KNOT) 545 return SNDRV_PCM_RATE_KNOT; 546 return rates; 547 } 548 549 /** 550 * snd_pcm_rate_mask_intersect - computes the intersection between two rate masks 551 * @rates_a: The first rate mask 552 * @rates_b: The second rate mask 553 * 554 * This function computes the rates that are supported by both rate masks passed 555 * to the function. It will take care of the special handling of 556 * SNDRV_PCM_RATE_CONTINUOUS and SNDRV_PCM_RATE_KNOT. 557 * 558 * Return: A rate mask containing the rates that are supported by both rates_a 559 * and rates_b. 560 */ 561 unsigned int snd_pcm_rate_mask_intersect(unsigned int rates_a, 562 unsigned int rates_b) 563 { 564 rates_a = snd_pcm_rate_mask_sanitize(rates_a); 565 rates_b = snd_pcm_rate_mask_sanitize(rates_b); 566 567 if (rates_a & SNDRV_PCM_RATE_CONTINUOUS) 568 return rates_b; 569 else if (rates_b & SNDRV_PCM_RATE_CONTINUOUS) 570 return rates_a; 571 else if (rates_a & SNDRV_PCM_RATE_KNOT) 572 return rates_b; 573 else if (rates_b & SNDRV_PCM_RATE_KNOT) 574 return rates_a; 575 return rates_a & rates_b; 576 } 577 EXPORT_SYMBOL_GPL(snd_pcm_rate_mask_intersect); 578 579 /** 580 * snd_pcm_rate_range_to_bits - converts rate range to SNDRV_PCM_RATE_xxx bit 581 * @rate_min: the minimum sample rate 582 * @rate_max: the maximum sample rate 583 * 584 * This function has an implicit assumption: the rates in the given range have 585 * only the pre-defined rates like 44100 or 16000. 586 * 587 * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate range, 588 * or SNDRV_PCM_RATE_KNOT for an unknown range. 589 */ 590 unsigned int snd_pcm_rate_range_to_bits(unsigned int rate_min, 591 unsigned int rate_max) 592 { 593 unsigned int rates = 0; 594 int i; 595 596 for (i = 0; i < snd_pcm_known_rates.count; i++) { 597 if (snd_pcm_known_rates.list[i] >= rate_min 598 && snd_pcm_known_rates.list[i] <= rate_max) 599 rates |= 1 << i; 600 } 601 602 if (!rates) 603 rates = SNDRV_PCM_RATE_KNOT; 604 605 return rates; 606 } 607 EXPORT_SYMBOL_GPL(snd_pcm_rate_range_to_bits); 608