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 */ 30struct 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 38static 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 */ 214int 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 224EXPORT_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 */ 233int 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 243EXPORT_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 */ 251int snd_pcm_format_linear(snd_pcm_format_t format) 252{ 253 return snd_pcm_format_signed(format) >= 0; 254} 255 256EXPORT_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 */ 265int 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 275EXPORT_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 */ 284int 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 294EXPORT_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 */ 303int 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 313EXPORT_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 */ 322int 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 332EXPORT_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 */ 342ssize_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 350EXPORT_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 */ 358const 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 367EXPORT_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 */ 379int 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 431EXPORT_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 */ 442int 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 460EXPORT_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 */ 469unsigned 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} 478EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit); 479