1 /* pcm.c 2 ** 3 ** Copyright 2011, The Android Open Source Project 4 ** 5 ** Redistribution and use in source and binary forms, with or without 6 ** modification, are permitted provided that the following conditions are met: 7 ** * Redistributions of source code must retain the above copyright 8 ** notice, this list of conditions and the following disclaimer. 9 ** * Redistributions in binary form must reproduce the above copyright 10 ** notice, this list of conditions and the following disclaimer in the 11 ** documentation and/or other materials provided with the distribution. 12 ** * Neither the name of The Android Open Source Project nor the names of 13 ** its contributors may be used to endorse or promote products derived 14 ** from this software without specific prior written permission. 15 ** 16 ** THIS SOFTWARE IS PROVIDED BY The Android Open Source Project ``AS IS'' AND 17 ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 ** ARE DISCLAIMED. IN NO EVENT SHALL The Android Open Source Project BE LIABLE 20 ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 22 ** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 23 ** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 26 ** DAMAGE. 27 */ 28 29 #include <stdio.h> 30 #include <stdlib.h> 31 #include <fcntl.h> 32 #include <stdarg.h> 33 #include <string.h> 34 #include <errno.h> 35 #include <unistd.h> 36 #include <poll.h> 37 38 #include <sys/ioctl.h> 39 #include <sys/mman.h> 40 #include <sys/time.h> 41 #include <limits.h> 42 43 #include <linux/ioctl.h> 44 #define __force 45 #define __bitwise 46 #define __user 47 #include <sound/asound.h> 48 49 #include <tinyalsa/asoundlib.h> 50 51 #define PARAM_MAX SNDRV_PCM_HW_PARAM_LAST_INTERVAL 52 53 /* Logs information into a string; follows snprintf() in that 54 * offset may be greater than size, and though no characters are copied 55 * into string, characters are still counted into offset. */ 56 #define STRLOG(string, offset, size, ...) \ 57 do { int temp, clipoffset = offset > size ? size : offset; \ 58 temp = snprintf(string + clipoffset, size - clipoffset, __VA_ARGS__); \ 59 if (temp > 0) offset += temp; } while (0) 60 61 #ifndef ARRAY_SIZE 62 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0])) 63 #endif 64 65 /* refer to SNDRV_PCM_ACCESS_##index in sound/asound.h. */ 66 static const char * const access_lookup[] = { 67 "MMAP_INTERLEAVED", 68 "MMAP_NONINTERLEAVED", 69 "MMAP_COMPLEX", 70 "RW_INTERLEAVED", 71 "RW_NONINTERLEAVED", 72 }; 73 74 /* refer to SNDRV_PCM_FORMAT_##index in sound/asound.h. */ 75 static const char * const format_lookup[] = { 76 /*[0] =*/ "S8", 77 "U8", 78 "S16_LE", 79 "S16_BE", 80 "U16_LE", 81 "U16_BE", 82 "S24_LE", 83 "S24_BE", 84 "U24_LE", 85 "U24_BE", 86 "S32_LE", 87 "S32_BE", 88 "U32_LE", 89 "U32_BE", 90 "FLOAT_LE", 91 "FLOAT_BE", 92 "FLOAT64_LE", 93 "FLOAT64_BE", 94 "IEC958_SUBFRAME_LE", 95 "IEC958_SUBFRAME_BE", 96 "MU_LAW", 97 "A_LAW", 98 "IMA_ADPCM", 99 "MPEG", 100 /*[24] =*/ "GSM", 101 /* gap */ 102 [31] = "SPECIAL", 103 "S24_3LE", 104 "S24_3BE", 105 "U24_3LE", 106 "U24_3BE", 107 "S20_3LE", 108 "S20_3BE", 109 "U20_3LE", 110 "U20_3BE", 111 "S18_3LE", 112 "S18_3BE", 113 "U18_3LE", 114 /*[43] =*/ "U18_3BE", 115 #if 0 116 /* recent additions, may not be present on local asound.h */ 117 "G723_24", 118 "G723_24_1B", 119 "G723_40", 120 "G723_40_1B", 121 "DSD_U8", 122 "DSD_U16_LE", 123 #endif 124 }; 125 126 /* refer to SNDRV_PCM_SUBFORMAT_##index in sound/asound.h. */ 127 static const char * const subformat_lookup[] = { 128 "STD", 129 }; 130 131 static inline int param_is_mask(int p) 132 { 133 return (p >= SNDRV_PCM_HW_PARAM_FIRST_MASK) && 134 (p <= SNDRV_PCM_HW_PARAM_LAST_MASK); 135 } 136 137 static inline int param_is_interval(int p) 138 { 139 return (p >= SNDRV_PCM_HW_PARAM_FIRST_INTERVAL) && 140 (p <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL); 141 } 142 143 static inline struct snd_interval *param_to_interval(struct snd_pcm_hw_params *p, int n) 144 { 145 return &(p->intervals[n - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL]); 146 } 147 148 static inline struct snd_mask *param_to_mask(struct snd_pcm_hw_params *p, int n) 149 { 150 return &(p->masks[n - SNDRV_PCM_HW_PARAM_FIRST_MASK]); 151 } 152 153 static void param_set_mask(struct snd_pcm_hw_params *p, int n, unsigned int bit) 154 { 155 if (bit >= SNDRV_MASK_MAX) 156 return; 157 if (param_is_mask(n)) { 158 struct snd_mask *m = param_to_mask(p, n); 159 m->bits[0] = 0; 160 m->bits[1] = 0; 161 m->bits[bit >> 5] |= (1 << (bit & 31)); 162 } 163 } 164 165 static void param_set_min(struct snd_pcm_hw_params *p, int n, unsigned int val) 166 { 167 if (param_is_interval(n)) { 168 struct snd_interval *i = param_to_interval(p, n); 169 i->min = val; 170 } 171 } 172 173 static unsigned int param_get_min(struct snd_pcm_hw_params *p, int n) 174 { 175 if (param_is_interval(n)) { 176 struct snd_interval *i = param_to_interval(p, n); 177 return i->min; 178 } 179 return 0; 180 } 181 182 static void param_set_max(struct snd_pcm_hw_params *p, int n, unsigned int val) 183 { 184 if (param_is_interval(n)) { 185 struct snd_interval *i = param_to_interval(p, n); 186 i->max = val; 187 } 188 } 189 190 static unsigned int param_get_max(struct snd_pcm_hw_params *p, int n) 191 { 192 if (param_is_interval(n)) { 193 struct snd_interval *i = param_to_interval(p, n); 194 return i->max; 195 } 196 return 0; 197 } 198 199 static void param_set_int(struct snd_pcm_hw_params *p, int n, unsigned int val) 200 { 201 if (param_is_interval(n)) { 202 struct snd_interval *i = param_to_interval(p, n); 203 i->min = val; 204 i->max = val; 205 i->integer = 1; 206 } 207 } 208 209 static unsigned int param_get_int(struct snd_pcm_hw_params *p, int n) 210 { 211 if (param_is_interval(n)) { 212 struct snd_interval *i = param_to_interval(p, n); 213 if (i->integer) 214 return i->max; 215 } 216 return 0; 217 } 218 219 static void param_init(struct snd_pcm_hw_params *p) 220 { 221 int n; 222 223 memset(p, 0, sizeof(*p)); 224 for (n = SNDRV_PCM_HW_PARAM_FIRST_MASK; 225 n <= SNDRV_PCM_HW_PARAM_LAST_MASK; n++) { 226 struct snd_mask *m = param_to_mask(p, n); 227 m->bits[0] = ~0; 228 m->bits[1] = ~0; 229 } 230 for (n = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; 231 n <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; n++) { 232 struct snd_interval *i = param_to_interval(p, n); 233 i->min = 0; 234 i->max = ~0; 235 } 236 p->rmask = ~0U; 237 p->cmask = 0; 238 p->info = ~0U; 239 } 240 241 #define PCM_ERROR_MAX 128 242 243 struct pcm { 244 int fd; 245 unsigned int flags; 246 int running:1; 247 int prepared:1; 248 int underruns; 249 unsigned int buffer_size; 250 unsigned int boundary; 251 char error[PCM_ERROR_MAX]; 252 struct pcm_config config; 253 struct snd_pcm_mmap_status *mmap_status; 254 struct snd_pcm_mmap_control *mmap_control; 255 struct snd_pcm_sync_ptr *sync_ptr; 256 void *mmap_buffer; 257 unsigned int noirq_frames_per_msec; 258 int wait_for_avail_min; 259 }; 260 261 unsigned int pcm_get_buffer_size(struct pcm *pcm) 262 { 263 return pcm->buffer_size; 264 } 265 266 const char* pcm_get_error(struct pcm *pcm) 267 { 268 return pcm->error; 269 } 270 271 static int oops(struct pcm *pcm, int e, const char *fmt, ...) 272 { 273 va_list ap; 274 int sz; 275 276 va_start(ap, fmt); 277 vsnprintf(pcm->error, PCM_ERROR_MAX, fmt, ap); 278 va_end(ap); 279 sz = strlen(pcm->error); 280 281 if (errno) 282 snprintf(pcm->error + sz, PCM_ERROR_MAX - sz, 283 ": %s", strerror(e)); 284 return -1; 285 } 286 287 static unsigned int pcm_format_to_alsa(enum pcm_format format) 288 { 289 switch (format) { 290 case PCM_FORMAT_S32_LE: 291 return SNDRV_PCM_FORMAT_S32_LE; 292 case PCM_FORMAT_S8: 293 return SNDRV_PCM_FORMAT_S8; 294 case PCM_FORMAT_S24_3LE: 295 return SNDRV_PCM_FORMAT_S24_3LE; 296 case PCM_FORMAT_S24_LE: 297 return SNDRV_PCM_FORMAT_S24_LE; 298 default: 299 case PCM_FORMAT_S16_LE: 300 return SNDRV_PCM_FORMAT_S16_LE; 301 }; 302 } 303 304 unsigned int pcm_format_to_bits(enum pcm_format format) 305 { 306 switch (format) { 307 case PCM_FORMAT_S32_LE: 308 case PCM_FORMAT_S24_LE: 309 return 32; 310 case PCM_FORMAT_S24_3LE: 311 return 24; 312 default: 313 case PCM_FORMAT_S16_LE: 314 return 16; 315 }; 316 } 317 318 unsigned int pcm_bytes_to_frames(struct pcm *pcm, unsigned int bytes) 319 { 320 return bytes / (pcm->config.channels * 321 (pcm_format_to_bits(pcm->config.format) >> 3)); 322 } 323 324 unsigned int pcm_frames_to_bytes(struct pcm *pcm, unsigned int frames) 325 { 326 return frames * pcm->config.channels * 327 (pcm_format_to_bits(pcm->config.format) >> 3); 328 } 329 330 static int pcm_sync_ptr(struct pcm *pcm, int flags) { 331 if (pcm->sync_ptr) { 332 pcm->sync_ptr->flags = flags; 333 if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_SYNC_PTR, pcm->sync_ptr) < 0) 334 return -1; 335 } 336 return 0; 337 } 338 339 static int pcm_hw_mmap_status(struct pcm *pcm) { 340 341 if (pcm->sync_ptr) 342 return 0; 343 344 int page_size = sysconf(_SC_PAGE_SIZE); 345 pcm->mmap_status = mmap(NULL, page_size, PROT_READ, MAP_FILE | MAP_SHARED, 346 pcm->fd, SNDRV_PCM_MMAP_OFFSET_STATUS); 347 if (pcm->mmap_status == MAP_FAILED) 348 pcm->mmap_status = NULL; 349 if (!pcm->mmap_status) 350 goto mmap_error; 351 352 pcm->mmap_control = mmap(NULL, page_size, PROT_READ | PROT_WRITE, 353 MAP_FILE | MAP_SHARED, pcm->fd, SNDRV_PCM_MMAP_OFFSET_CONTROL); 354 if (pcm->mmap_control == MAP_FAILED) 355 pcm->mmap_control = NULL; 356 if (!pcm->mmap_control) { 357 munmap(pcm->mmap_status, page_size); 358 pcm->mmap_status = NULL; 359 goto mmap_error; 360 } 361 if (pcm->flags & PCM_MMAP) 362 pcm->mmap_control->avail_min = pcm->config.avail_min; 363 else 364 pcm->mmap_control->avail_min = 1; 365 366 return 0; 367 368 mmap_error: 369 370 pcm->sync_ptr = calloc(1, sizeof(*pcm->sync_ptr)); 371 if (!pcm->sync_ptr) 372 return -ENOMEM; 373 pcm->mmap_status = &pcm->sync_ptr->s.status; 374 pcm->mmap_control = &pcm->sync_ptr->c.control; 375 if (pcm->flags & PCM_MMAP) 376 pcm->mmap_control->avail_min = pcm->config.avail_min; 377 else 378 pcm->mmap_control->avail_min = 1; 379 380 pcm_sync_ptr(pcm, 0); 381 382 return 0; 383 } 384 385 static void pcm_hw_munmap_status(struct pcm *pcm) { 386 if (pcm->sync_ptr) { 387 free(pcm->sync_ptr); 388 pcm->sync_ptr = NULL; 389 } else { 390 int page_size = sysconf(_SC_PAGE_SIZE); 391 if (pcm->mmap_status) 392 munmap(pcm->mmap_status, page_size); 393 if (pcm->mmap_control) 394 munmap(pcm->mmap_control, page_size); 395 } 396 pcm->mmap_status = NULL; 397 pcm->mmap_control = NULL; 398 } 399 400 static int pcm_areas_copy(struct pcm *pcm, unsigned int pcm_offset, 401 char *buf, unsigned int src_offset, 402 unsigned int frames) 403 { 404 int size_bytes = pcm_frames_to_bytes(pcm, frames); 405 int pcm_offset_bytes = pcm_frames_to_bytes(pcm, pcm_offset); 406 int src_offset_bytes = pcm_frames_to_bytes(pcm, src_offset); 407 408 /* interleaved only atm */ 409 if (pcm->flags & PCM_IN) 410 memcpy(buf + src_offset_bytes, 411 (char*)pcm->mmap_buffer + pcm_offset_bytes, 412 size_bytes); 413 else 414 memcpy((char*)pcm->mmap_buffer + pcm_offset_bytes, 415 buf + src_offset_bytes, 416 size_bytes); 417 return 0; 418 } 419 420 static int pcm_mmap_transfer_areas(struct pcm *pcm, char *buf, 421 unsigned int offset, unsigned int size) 422 { 423 void *pcm_areas; 424 int commit; 425 unsigned int pcm_offset, frames, count = 0; 426 427 while (size > 0) { 428 frames = size; 429 pcm_mmap_begin(pcm, &pcm_areas, &pcm_offset, &frames); 430 pcm_areas_copy(pcm, pcm_offset, buf, offset, frames); 431 commit = pcm_mmap_commit(pcm, pcm_offset, frames); 432 if (commit < 0) { 433 oops(pcm, commit, "failed to commit %d frames\n", frames); 434 return commit; 435 } 436 437 offset += commit; 438 count += commit; 439 size -= commit; 440 } 441 return count; 442 } 443 444 int pcm_get_htimestamp(struct pcm *pcm, unsigned int *avail, 445 struct timespec *tstamp) 446 { 447 int frames; 448 int rc; 449 snd_pcm_uframes_t hw_ptr; 450 451 if (!pcm_is_ready(pcm)) 452 return -1; 453 454 rc = pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_APPL|SNDRV_PCM_SYNC_PTR_HWSYNC); 455 if (rc < 0) 456 return -1; 457 458 if ((pcm->mmap_status->state != PCM_STATE_RUNNING) && 459 (pcm->mmap_status->state != PCM_STATE_DRAINING)) 460 return -1; 461 462 *tstamp = pcm->mmap_status->tstamp; 463 if (tstamp->tv_sec == 0 && tstamp->tv_nsec == 0) 464 return -1; 465 466 hw_ptr = pcm->mmap_status->hw_ptr; 467 if (pcm->flags & PCM_IN) 468 frames = hw_ptr - pcm->mmap_control->appl_ptr; 469 else 470 frames = hw_ptr + pcm->buffer_size - pcm->mmap_control->appl_ptr; 471 472 if (frames < 0) 473 frames += pcm->boundary; 474 else if (frames > (int)pcm->boundary) 475 frames -= pcm->boundary; 476 477 *avail = (unsigned int)frames; 478 479 return 0; 480 } 481 482 int pcm_write(struct pcm *pcm, const void *data, unsigned int count) 483 { 484 struct snd_xferi x; 485 486 if (pcm->flags & PCM_IN) 487 return -EINVAL; 488 489 x.buf = (void*)data; 490 x.frames = count / (pcm->config.channels * 491 pcm_format_to_bits(pcm->config.format) / 8); 492 493 for (;;) { 494 if (!pcm->running) { 495 int prepare_error = pcm_prepare(pcm); 496 if (prepare_error) 497 return prepare_error; 498 if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_WRITEI_FRAMES, &x)) 499 return oops(pcm, errno, "cannot write initial data"); 500 pcm->running = 1; 501 return 0; 502 } 503 if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_WRITEI_FRAMES, &x)) { 504 pcm->prepared = 0; 505 pcm->running = 0; 506 if (errno == EPIPE) { 507 /* we failed to make our window -- try to restart if we are 508 * allowed to do so. Otherwise, simply allow the EPIPE error to 509 * propagate up to the app level */ 510 pcm->underruns++; 511 if (pcm->flags & PCM_NORESTART) 512 return -EPIPE; 513 continue; 514 } 515 return oops(pcm, errno, "cannot write stream data"); 516 } 517 return 0; 518 } 519 } 520 521 int pcm_read(struct pcm *pcm, void *data, unsigned int count) 522 { 523 struct snd_xferi x; 524 525 if (!(pcm->flags & PCM_IN)) 526 return -EINVAL; 527 528 x.buf = data; 529 x.frames = count / (pcm->config.channels * 530 pcm_format_to_bits(pcm->config.format) / 8); 531 532 for (;;) { 533 if (!pcm->running) { 534 if (pcm_start(pcm) < 0) { 535 fprintf(stderr, "start error"); 536 return -errno; 537 } 538 } 539 if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_READI_FRAMES, &x)) { 540 pcm->prepared = 0; 541 pcm->running = 0; 542 if (errno == EPIPE) { 543 /* we failed to make our window -- try to restart */ 544 pcm->underruns++; 545 continue; 546 } 547 return oops(pcm, errno, "cannot read stream data"); 548 } 549 return 0; 550 } 551 } 552 553 static struct pcm bad_pcm = { 554 .fd = -1, 555 }; 556 557 struct pcm_params *pcm_params_get(unsigned int card, unsigned int device, 558 unsigned int flags) 559 { 560 struct snd_pcm_hw_params *params; 561 char fn[256]; 562 int fd; 563 564 snprintf(fn, sizeof(fn), "/dev/snd/pcmC%uD%u%c", card, device, 565 flags & PCM_IN ? 'c' : 'p'); 566 567 fd = open(fn, O_RDWR); 568 if (fd < 0) { 569 fprintf(stderr, "cannot open device '%s'\n", fn); 570 goto err_open; 571 } 572 573 params = calloc(1, sizeof(struct snd_pcm_hw_params)); 574 if (!params) 575 goto err_calloc; 576 577 param_init(params); 578 if (ioctl(fd, SNDRV_PCM_IOCTL_HW_REFINE, params)) { 579 fprintf(stderr, "SNDRV_PCM_IOCTL_HW_REFINE error (%d)\n", errno); 580 goto err_hw_refine; 581 } 582 583 close(fd); 584 585 return (struct pcm_params *)params; 586 587 err_hw_refine: 588 free(params); 589 err_calloc: 590 close(fd); 591 err_open: 592 return NULL; 593 } 594 595 void pcm_params_free(struct pcm_params *pcm_params) 596 { 597 struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; 598 599 if (params) 600 free(params); 601 } 602 603 static int pcm_param_to_alsa(enum pcm_param param) 604 { 605 switch (param) { 606 case PCM_PARAM_ACCESS: 607 return SNDRV_PCM_HW_PARAM_ACCESS; 608 case PCM_PARAM_FORMAT: 609 return SNDRV_PCM_HW_PARAM_FORMAT; 610 case PCM_PARAM_SUBFORMAT: 611 return SNDRV_PCM_HW_PARAM_SUBFORMAT; 612 case PCM_PARAM_SAMPLE_BITS: 613 return SNDRV_PCM_HW_PARAM_SAMPLE_BITS; 614 break; 615 case PCM_PARAM_FRAME_BITS: 616 return SNDRV_PCM_HW_PARAM_FRAME_BITS; 617 break; 618 case PCM_PARAM_CHANNELS: 619 return SNDRV_PCM_HW_PARAM_CHANNELS; 620 break; 621 case PCM_PARAM_RATE: 622 return SNDRV_PCM_HW_PARAM_RATE; 623 break; 624 case PCM_PARAM_PERIOD_TIME: 625 return SNDRV_PCM_HW_PARAM_PERIOD_TIME; 626 break; 627 case PCM_PARAM_PERIOD_SIZE: 628 return SNDRV_PCM_HW_PARAM_PERIOD_SIZE; 629 break; 630 case PCM_PARAM_PERIOD_BYTES: 631 return SNDRV_PCM_HW_PARAM_PERIOD_BYTES; 632 break; 633 case PCM_PARAM_PERIODS: 634 return SNDRV_PCM_HW_PARAM_PERIODS; 635 break; 636 case PCM_PARAM_BUFFER_TIME: 637 return SNDRV_PCM_HW_PARAM_BUFFER_TIME; 638 break; 639 case PCM_PARAM_BUFFER_SIZE: 640 return SNDRV_PCM_HW_PARAM_BUFFER_SIZE; 641 break; 642 case PCM_PARAM_BUFFER_BYTES: 643 return SNDRV_PCM_HW_PARAM_BUFFER_BYTES; 644 break; 645 case PCM_PARAM_TICK_TIME: 646 return SNDRV_PCM_HW_PARAM_TICK_TIME; 647 break; 648 649 default: 650 return -1; 651 } 652 } 653 654 struct pcm_mask *pcm_params_get_mask(struct pcm_params *pcm_params, 655 enum pcm_param param) 656 { 657 int p; 658 struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; 659 if (params == NULL) { 660 return NULL; 661 } 662 663 p = pcm_param_to_alsa(param); 664 if (p < 0 || !param_is_mask(p)) { 665 return NULL; 666 } 667 668 return (struct pcm_mask *)param_to_mask(params, p); 669 } 670 671 unsigned int pcm_params_get_min(struct pcm_params *pcm_params, 672 enum pcm_param param) 673 { 674 struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; 675 int p; 676 677 if (!params) 678 return 0; 679 680 p = pcm_param_to_alsa(param); 681 if (p < 0) 682 return 0; 683 684 return param_get_min(params, p); 685 } 686 687 void pcm_params_set_min(struct pcm_params *pcm_params, 688 enum pcm_param param, unsigned int val) 689 { 690 struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; 691 int p; 692 693 if (!params) 694 return; 695 696 p = pcm_param_to_alsa(param); 697 if (p < 0) 698 return; 699 700 param_set_min(params, p, val); 701 } 702 703 unsigned int pcm_params_get_max(struct pcm_params *pcm_params, 704 enum pcm_param param) 705 { 706 struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; 707 int p; 708 709 if (!params) 710 return 0; 711 712 p = pcm_param_to_alsa(param); 713 if (p < 0) 714 return 0; 715 716 return param_get_max(params, p); 717 } 718 719 void pcm_params_set_max(struct pcm_params *pcm_params, 720 enum pcm_param param, unsigned int val) 721 { 722 struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; 723 int p; 724 725 if (!params) 726 return; 727 728 p = pcm_param_to_alsa(param); 729 if (p < 0) 730 return; 731 732 param_set_max(params, p, val); 733 } 734 735 static int pcm_mask_test(struct pcm_mask *m, unsigned int index) 736 { 737 const unsigned int bitshift = 5; /* for 32 bit integer */ 738 const unsigned int bitmask = (1 << bitshift) - 1; 739 unsigned int element; 740 741 element = index >> bitshift; 742 if (element >= ARRAY_SIZE(m->bits)) 743 return 0; /* for safety, but should never occur */ 744 return (m->bits[element] >> (index & bitmask)) & 1; 745 } 746 747 static int pcm_mask_to_string(struct pcm_mask *m, char *string, unsigned int size, 748 char *mask_name, 749 const char * const *bit_array_name, size_t bit_array_size) 750 { 751 unsigned int i; 752 unsigned int offset = 0; 753 754 if (m == NULL) 755 return 0; 756 if (bit_array_size < 32) { 757 STRLOG(string, offset, size, "%12s:\t%#08x\n", mask_name, m->bits[0]); 758 } else { /* spans two or more bitfields, print with an array index */ 759 for (i = 0; i < (bit_array_size + 31) >> 5; ++i) { 760 STRLOG(string, offset, size, "%9s[%d]:\t%#08x\n", 761 mask_name, i, m->bits[i]); 762 } 763 } 764 for (i = 0; i < bit_array_size; ++i) { 765 if (pcm_mask_test(m, i)) { 766 STRLOG(string, offset, size, "%12s \t%s\n", "", bit_array_name[i]); 767 } 768 } 769 return offset; 770 } 771 772 int pcm_params_to_string(struct pcm_params *params, char *string, unsigned int size) 773 { 774 struct pcm_mask *m; 775 unsigned int min, max; 776 unsigned int clipoffset, offset; 777 778 m = pcm_params_get_mask(params, PCM_PARAM_ACCESS); 779 offset = pcm_mask_to_string(m, string, size, 780 "Access", access_lookup, ARRAY_SIZE(access_lookup)); 781 m = pcm_params_get_mask(params, PCM_PARAM_FORMAT); 782 clipoffset = offset > size ? size : offset; 783 offset += pcm_mask_to_string(m, string + clipoffset, size - clipoffset, 784 "Format", format_lookup, ARRAY_SIZE(format_lookup)); 785 m = pcm_params_get_mask(params, PCM_PARAM_SUBFORMAT); 786 clipoffset = offset > size ? size : offset; 787 offset += pcm_mask_to_string(m, string + clipoffset, size - clipoffset, 788 "Subformat", subformat_lookup, ARRAY_SIZE(subformat_lookup)); 789 min = pcm_params_get_min(params, PCM_PARAM_RATE); 790 max = pcm_params_get_max(params, PCM_PARAM_RATE); 791 STRLOG(string, offset, size, " Rate:\tmin=%uHz\tmax=%uHz\n", min, max); 792 min = pcm_params_get_min(params, PCM_PARAM_CHANNELS); 793 max = pcm_params_get_max(params, PCM_PARAM_CHANNELS); 794 STRLOG(string, offset, size, " Channels:\tmin=%u\t\tmax=%u\n", min, max); 795 min = pcm_params_get_min(params, PCM_PARAM_SAMPLE_BITS); 796 max = pcm_params_get_max(params, PCM_PARAM_SAMPLE_BITS); 797 STRLOG(string, offset, size, " Sample bits:\tmin=%u\t\tmax=%u\n", min, max); 798 min = pcm_params_get_min(params, PCM_PARAM_PERIOD_SIZE); 799 max = pcm_params_get_max(params, PCM_PARAM_PERIOD_SIZE); 800 STRLOG(string, offset, size, " Period size:\tmin=%u\t\tmax=%u\n", min, max); 801 min = pcm_params_get_min(params, PCM_PARAM_PERIODS); 802 max = pcm_params_get_max(params, PCM_PARAM_PERIODS); 803 STRLOG(string, offset, size, "Period count:\tmin=%u\t\tmax=%u\n", min, max); 804 return offset; 805 } 806 807 int pcm_params_format_test(struct pcm_params *params, enum pcm_format format) 808 { 809 unsigned int alsa_format = pcm_format_to_alsa(format); 810 811 if (alsa_format == SNDRV_PCM_FORMAT_S16_LE && format != PCM_FORMAT_S16_LE) 812 return 0; /* caution: format not recognized is equivalent to S16_LE */ 813 return pcm_mask_test(pcm_params_get_mask(params, PCM_PARAM_FORMAT), alsa_format); 814 } 815 816 int pcm_close(struct pcm *pcm) 817 { 818 if (pcm == &bad_pcm) 819 return 0; 820 821 pcm_hw_munmap_status(pcm); 822 823 if (pcm->flags & PCM_MMAP) { 824 pcm_stop(pcm); 825 munmap(pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size)); 826 } 827 828 if (pcm->fd >= 0) 829 close(pcm->fd); 830 pcm->prepared = 0; 831 pcm->running = 0; 832 pcm->buffer_size = 0; 833 pcm->fd = -1; 834 free(pcm); 835 return 0; 836 } 837 838 struct pcm *pcm_open(unsigned int card, unsigned int device, 839 unsigned int flags, struct pcm_config *config) 840 { 841 struct pcm *pcm; 842 struct snd_pcm_info info; 843 struct snd_pcm_hw_params params; 844 struct snd_pcm_sw_params sparams; 845 char fn[256]; 846 int rc; 847 848 pcm = calloc(1, sizeof(struct pcm)); 849 if (!pcm || !config) 850 return &bad_pcm; /* TODO: could support default config here */ 851 852 pcm->config = *config; 853 854 snprintf(fn, sizeof(fn), "/dev/snd/pcmC%uD%u%c", card, device, 855 flags & PCM_IN ? 'c' : 'p'); 856 857 pcm->flags = flags; 858 pcm->fd = open(fn, O_RDWR|O_NONBLOCK); 859 if (pcm->fd < 0) { 860 oops(pcm, errno, "cannot open device '%s'", fn); 861 return pcm; 862 } 863 864 if (fcntl(pcm->fd, F_SETFL, fcntl(pcm->fd, F_GETFL) & 865 ~O_NONBLOCK) < 0) { 866 oops(pcm, errno, "failed to reset blocking mode '%s'", fn); 867 goto fail_close; 868 } 869 870 if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_INFO, &info)) { 871 oops(pcm, errno, "cannot get info"); 872 goto fail_close; 873 } 874 875 param_init(¶ms); 876 param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_FORMAT, 877 pcm_format_to_alsa(config->format)); 878 param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_SUBFORMAT, 879 SNDRV_PCM_SUBFORMAT_STD); 880 param_set_min(¶ms, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, config->period_size); 881 param_set_int(¶ms, SNDRV_PCM_HW_PARAM_SAMPLE_BITS, 882 pcm_format_to_bits(config->format)); 883 param_set_int(¶ms, SNDRV_PCM_HW_PARAM_FRAME_BITS, 884 pcm_format_to_bits(config->format) * config->channels); 885 param_set_int(¶ms, SNDRV_PCM_HW_PARAM_CHANNELS, 886 config->channels); 887 param_set_int(¶ms, SNDRV_PCM_HW_PARAM_PERIODS, config->period_count); 888 param_set_int(¶ms, SNDRV_PCM_HW_PARAM_RATE, config->rate); 889 890 if (flags & PCM_NOIRQ) { 891 if (!(flags & PCM_MMAP)) { 892 oops(pcm, -EINVAL, "noirq only currently supported with mmap()."); 893 goto fail_close; 894 } 895 896 params.flags |= SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP; 897 pcm->noirq_frames_per_msec = config->rate / 1000; 898 } 899 900 if (flags & PCM_MMAP) 901 param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_ACCESS, 902 SNDRV_PCM_ACCESS_MMAP_INTERLEAVED); 903 else 904 param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_ACCESS, 905 SNDRV_PCM_ACCESS_RW_INTERLEAVED); 906 907 if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_HW_PARAMS, ¶ms)) { 908 oops(pcm, errno, "cannot set hw params"); 909 goto fail_close; 910 } 911 912 /* get our refined hw_params */ 913 config->period_size = param_get_int(¶ms, SNDRV_PCM_HW_PARAM_PERIOD_SIZE); 914 config->period_count = param_get_int(¶ms, SNDRV_PCM_HW_PARAM_PERIODS); 915 pcm->buffer_size = config->period_count * config->period_size; 916 917 if (flags & PCM_MMAP) { 918 pcm->mmap_buffer = mmap(NULL, pcm_frames_to_bytes(pcm, pcm->buffer_size), 919 PROT_READ | PROT_WRITE, MAP_FILE | MAP_SHARED, pcm->fd, 0); 920 if (pcm->mmap_buffer == MAP_FAILED) { 921 oops(pcm, -errno, "failed to mmap buffer %d bytes\n", 922 pcm_frames_to_bytes(pcm, pcm->buffer_size)); 923 goto fail_close; 924 } 925 } 926 927 memset(&sparams, 0, sizeof(sparams)); 928 sparams.tstamp_mode = SNDRV_PCM_TSTAMP_ENABLE; 929 sparams.period_step = 1; 930 931 if (!config->start_threshold) { 932 if (pcm->flags & PCM_IN) 933 pcm->config.start_threshold = sparams.start_threshold = 1; 934 else 935 pcm->config.start_threshold = sparams.start_threshold = 936 config->period_count * config->period_size / 2; 937 } else 938 sparams.start_threshold = config->start_threshold; 939 940 /* pick a high stop threshold - todo: does this need further tuning */ 941 if (!config->stop_threshold) { 942 if (pcm->flags & PCM_IN) 943 pcm->config.stop_threshold = sparams.stop_threshold = 944 config->period_count * config->period_size * 10; 945 else 946 pcm->config.stop_threshold = sparams.stop_threshold = 947 config->period_count * config->period_size; 948 } 949 else 950 sparams.stop_threshold = config->stop_threshold; 951 952 if (!pcm->config.avail_min) { 953 if (pcm->flags & PCM_MMAP) 954 pcm->config.avail_min = sparams.avail_min = pcm->config.period_size; 955 else 956 pcm->config.avail_min = sparams.avail_min = 1; 957 } else 958 sparams.avail_min = config->avail_min; 959 960 sparams.xfer_align = config->period_size / 2; /* needed for old kernels */ 961 sparams.silence_threshold = config->silence_threshold; 962 sparams.silence_size = config->silence_size; 963 pcm->boundary = sparams.boundary = pcm->buffer_size; 964 965 while (pcm->boundary * 2 <= INT_MAX - pcm->buffer_size) 966 pcm->boundary *= 2; 967 968 if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_SW_PARAMS, &sparams)) { 969 oops(pcm, errno, "cannot set sw params"); 970 goto fail; 971 } 972 973 rc = pcm_hw_mmap_status(pcm); 974 if (rc < 0) { 975 oops(pcm, rc, "mmap status failed"); 976 goto fail; 977 } 978 979 #ifdef SNDRV_PCM_IOCTL_TTSTAMP 980 if (pcm->flags & PCM_MONOTONIC) { 981 int arg = SNDRV_PCM_TSTAMP_TYPE_MONOTONIC; 982 rc = ioctl(pcm->fd, SNDRV_PCM_IOCTL_TTSTAMP, &arg); 983 if (rc < 0) { 984 oops(pcm, rc, "cannot set timestamp type"); 985 goto fail; 986 } 987 } 988 #endif 989 990 pcm->underruns = 0; 991 return pcm; 992 993 fail: 994 if (flags & PCM_MMAP) 995 munmap(pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size)); 996 fail_close: 997 close(pcm->fd); 998 pcm->fd = -1; 999 return pcm; 1000 } 1001 1002 int pcm_is_ready(struct pcm *pcm) 1003 { 1004 return pcm->fd >= 0; 1005 } 1006 1007 int pcm_prepare(struct pcm *pcm) 1008 { 1009 if (pcm->prepared) 1010 return 0; 1011 1012 if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_PREPARE) < 0) 1013 return oops(pcm, errno, "cannot prepare channel"); 1014 1015 pcm->prepared = 1; 1016 return 0; 1017 } 1018 1019 int pcm_start(struct pcm *pcm) 1020 { 1021 int prepare_error = pcm_prepare(pcm); 1022 if (prepare_error) 1023 return prepare_error; 1024 1025 if (pcm->flags & PCM_MMAP) 1026 pcm_sync_ptr(pcm, 0); 1027 1028 if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_START) < 0) 1029 return oops(pcm, errno, "cannot start channel"); 1030 1031 pcm->running = 1; 1032 return 0; 1033 } 1034 1035 int pcm_stop(struct pcm *pcm) 1036 { 1037 if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_DROP) < 0) 1038 return oops(pcm, errno, "cannot stop channel"); 1039 1040 pcm->prepared = 0; 1041 pcm->running = 0; 1042 return 0; 1043 } 1044 1045 static inline int pcm_mmap_playback_avail(struct pcm *pcm) 1046 { 1047 int avail; 1048 1049 avail = pcm->mmap_status->hw_ptr + pcm->buffer_size - pcm->mmap_control->appl_ptr; 1050 1051 if (avail < 0) 1052 avail += pcm->boundary; 1053 else if (avail > (int)pcm->boundary) 1054 avail -= pcm->boundary; 1055 1056 return avail; 1057 } 1058 1059 static inline int pcm_mmap_capture_avail(struct pcm *pcm) 1060 { 1061 int avail = pcm->mmap_status->hw_ptr - pcm->mmap_control->appl_ptr; 1062 if (avail < 0) 1063 avail += pcm->boundary; 1064 return avail; 1065 } 1066 1067 int pcm_mmap_avail(struct pcm *pcm) 1068 { 1069 pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_HWSYNC); 1070 if (pcm->flags & PCM_IN) 1071 return pcm_mmap_capture_avail(pcm); 1072 else 1073 return pcm_mmap_playback_avail(pcm); 1074 } 1075 1076 static void pcm_mmap_appl_forward(struct pcm *pcm, int frames) 1077 { 1078 unsigned int appl_ptr = pcm->mmap_control->appl_ptr; 1079 appl_ptr += frames; 1080 1081 /* check for boundary wrap */ 1082 if (appl_ptr > pcm->boundary) 1083 appl_ptr -= pcm->boundary; 1084 pcm->mmap_control->appl_ptr = appl_ptr; 1085 } 1086 1087 int pcm_mmap_begin(struct pcm *pcm, void **areas, unsigned int *offset, 1088 unsigned int *frames) 1089 { 1090 unsigned int continuous, copy_frames, avail; 1091 1092 /* return the mmap buffer */ 1093 *areas = pcm->mmap_buffer; 1094 1095 /* and the application offset in frames */ 1096 *offset = pcm->mmap_control->appl_ptr % pcm->buffer_size; 1097 1098 avail = pcm_mmap_avail(pcm); 1099 if (avail > pcm->buffer_size) 1100 avail = pcm->buffer_size; 1101 continuous = pcm->buffer_size - *offset; 1102 1103 /* we can only copy frames if the are availabale and continuos */ 1104 copy_frames = *frames; 1105 if (copy_frames > avail) 1106 copy_frames = avail; 1107 if (copy_frames > continuous) 1108 copy_frames = continuous; 1109 *frames = copy_frames; 1110 1111 return 0; 1112 } 1113 1114 int pcm_mmap_commit(struct pcm *pcm, unsigned int offset __attribute__((unused)), unsigned int frames) 1115 { 1116 /* update the application pointer in userspace and kernel */ 1117 pcm_mmap_appl_forward(pcm, frames); 1118 pcm_sync_ptr(pcm, 0); 1119 1120 return frames; 1121 } 1122 1123 int pcm_avail_update(struct pcm *pcm) 1124 { 1125 pcm_sync_ptr(pcm, 0); 1126 return pcm_mmap_avail(pcm); 1127 } 1128 1129 int pcm_state(struct pcm *pcm) 1130 { 1131 int err = pcm_sync_ptr(pcm, 0); 1132 if (err < 0) 1133 return err; 1134 1135 return pcm->mmap_status->state; 1136 } 1137 1138 int pcm_set_avail_min(struct pcm *pcm, int avail_min) 1139 { 1140 if ((~pcm->flags) & (PCM_MMAP | PCM_NOIRQ)) 1141 return -ENOSYS; 1142 1143 pcm->config.avail_min = avail_min; 1144 return 0; 1145 } 1146 1147 int pcm_wait(struct pcm *pcm, int timeout) 1148 { 1149 struct pollfd pfd; 1150 int err; 1151 1152 pfd.fd = pcm->fd; 1153 pfd.events = POLLOUT | POLLERR | POLLNVAL; 1154 1155 do { 1156 /* let's wait for avail or timeout */ 1157 err = poll(&pfd, 1, timeout); 1158 if (err < 0) 1159 return -errno; 1160 1161 /* timeout ? */ 1162 if (err == 0) 1163 return 0; 1164 1165 /* have we been interrupted ? */ 1166 if (errno == -EINTR) 1167 continue; 1168 1169 /* check for any errors */ 1170 if (pfd.revents & (POLLERR | POLLNVAL)) { 1171 switch (pcm_state(pcm)) { 1172 case PCM_STATE_XRUN: 1173 return -EPIPE; 1174 case PCM_STATE_SUSPENDED: 1175 return -ESTRPIPE; 1176 case PCM_STATE_DISCONNECTED: 1177 return -ENODEV; 1178 default: 1179 return -EIO; 1180 } 1181 } 1182 /* poll again if fd not ready for IO */ 1183 } while (!(pfd.revents & (POLLIN | POLLOUT))); 1184 1185 return 1; 1186 } 1187 1188 int pcm_get_poll_fd(struct pcm *pcm) 1189 { 1190 return pcm->fd; 1191 } 1192 1193 int pcm_mmap_transfer(struct pcm *pcm, const void *buffer, unsigned int bytes) 1194 { 1195 int err = 0, frames, avail; 1196 unsigned int offset = 0, count; 1197 1198 if (bytes == 0) 1199 return 0; 1200 1201 count = pcm_bytes_to_frames(pcm, bytes); 1202 1203 while (count > 0) { 1204 1205 /* get the available space for writing new frames */ 1206 avail = pcm_avail_update(pcm); 1207 if (avail < 0) { 1208 fprintf(stderr, "cannot determine available mmap frames"); 1209 return err; 1210 } 1211 1212 /* start the audio if we reach the threshold */ 1213 if (!pcm->running && 1214 (pcm->buffer_size - avail) >= pcm->config.start_threshold) { 1215 if (pcm_start(pcm) < 0) { 1216 fprintf(stderr, "start error: hw 0x%x app 0x%x avail 0x%x\n", 1217 (unsigned int)pcm->mmap_status->hw_ptr, 1218 (unsigned int)pcm->mmap_control->appl_ptr, 1219 avail); 1220 return -errno; 1221 } 1222 pcm->wait_for_avail_min = 0; 1223 } 1224 1225 /* sleep until we have space to write new frames */ 1226 if (pcm->running) { 1227 /* enable waiting for avail_min threshold when less frames than we have to write 1228 * are available. */ 1229 if (!pcm->wait_for_avail_min && (count > (unsigned int)avail)) 1230 pcm->wait_for_avail_min = 1; 1231 1232 if (pcm->wait_for_avail_min && (avail < pcm->config.avail_min)) { 1233 int time = -1; 1234 1235 /* disable waiting for avail_min threshold to allow small amounts of data to be 1236 * written without waiting as long as there is enough room in buffer. */ 1237 pcm->wait_for_avail_min = 0; 1238 1239 if (pcm->flags & PCM_NOIRQ) 1240 time = (pcm->config.avail_min - avail) / pcm->noirq_frames_per_msec; 1241 1242 err = pcm_wait(pcm, time); 1243 if (err < 0) { 1244 pcm->prepared = 0; 1245 pcm->running = 0; 1246 oops(pcm, err, "wait error: hw 0x%x app 0x%x avail 0x%x\n", 1247 (unsigned int)pcm->mmap_status->hw_ptr, 1248 (unsigned int)pcm->mmap_control->appl_ptr, 1249 avail); 1250 pcm->mmap_control->appl_ptr = 0; 1251 return err; 1252 } 1253 continue; 1254 } 1255 } 1256 1257 frames = count; 1258 if (frames > avail) 1259 frames = avail; 1260 1261 if (!frames) 1262 break; 1263 1264 /* copy frames from buffer */ 1265 frames = pcm_mmap_transfer_areas(pcm, (void *)buffer, offset, frames); 1266 if (frames < 0) { 1267 fprintf(stderr, "write error: hw 0x%x app 0x%x avail 0x%x\n", 1268 (unsigned int)pcm->mmap_status->hw_ptr, 1269 (unsigned int)pcm->mmap_control->appl_ptr, 1270 avail); 1271 return frames; 1272 } 1273 1274 offset += frames; 1275 count -= frames; 1276 } 1277 1278 return 0; 1279 } 1280 1281 int pcm_mmap_write(struct pcm *pcm, const void *data, unsigned int count) 1282 { 1283 if ((~pcm->flags) & (PCM_OUT | PCM_MMAP)) 1284 return -ENOSYS; 1285 1286 return pcm_mmap_transfer(pcm, (void *)data, count); 1287 } 1288 1289 int pcm_mmap_read(struct pcm *pcm, void *data, unsigned int count) 1290 { 1291 if ((~pcm->flags) & (PCM_IN | PCM_MMAP)) 1292 return -ENOSYS; 1293 1294 return pcm_mmap_transfer(pcm, data, count); 1295 } 1296 1297 int pcm_ioctl(struct pcm *pcm, int request, ...) 1298 { 1299 va_list ap; 1300 void * arg; 1301 1302 if (!pcm_is_ready(pcm)) 1303 return -1; 1304 1305 va_start(ap, request); 1306 arg = va_arg(ap, void *); 1307 va_end(ap); 1308 1309 return ioctl(pcm->fd, request, arg); 1310 } 1311
