1 /* 2 * oxfw_stream.c - a part of driver for OXFW970/971 based devices 3 * 4 * Copyright (c) 2014 Takashi Sakamoto 5 * 6 * Licensed under the terms of the GNU General Public License, version 2. 7 */ 8 9 #include "oxfw.h" 10 #include <linux/delay.h> 11 12 #define AVC_GENERIC_FRAME_MAXIMUM_BYTES 512 13 #define CALLBACK_TIMEOUT 200 14 15 /* 16 * According to datasheet of Oxford Semiconductor: 17 * OXFW970: 32.0/44.1/48.0/96.0 Khz, 8 audio channels I/O 18 * OXFW971: 32.0/44.1/48.0/88.2/96.0/192.0 kHz, 16 audio channels I/O, MIDI I/O 19 */ 20 static const unsigned int oxfw_rate_table[] = { 21 [0] = 32000, 22 [1] = 44100, 23 [2] = 48000, 24 [3] = 88200, 25 [4] = 96000, 26 [5] = 192000, 27 }; 28 29 /* 30 * See Table 5.7 – Sampling frequency for Multi-bit Audio 31 * in AV/C Stream Format Information Specification 1.1 (Apr 2005, 1394TA) 32 */ 33 static const unsigned int avc_stream_rate_table[] = { 34 [0] = 0x02, 35 [1] = 0x03, 36 [2] = 0x04, 37 [3] = 0x0a, 38 [4] = 0x05, 39 [5] = 0x07, 40 }; 41 42 static int set_rate(struct snd_oxfw *oxfw, unsigned int rate) 43 { 44 int err; 45 46 err = avc_general_set_sig_fmt(oxfw->unit, rate, 47 AVC_GENERAL_PLUG_DIR_IN, 0); 48 if (err < 0) 49 goto end; 50 51 if (oxfw->has_output) 52 err = avc_general_set_sig_fmt(oxfw->unit, rate, 53 AVC_GENERAL_PLUG_DIR_OUT, 0); 54 end: 55 return err; 56 } 57 58 static int set_stream_format(struct snd_oxfw *oxfw, struct amdtp_stream *s, 59 unsigned int rate, unsigned int pcm_channels) 60 { 61 u8 **formats; 62 struct snd_oxfw_stream_formation formation; 63 enum avc_general_plug_dir dir; 64 unsigned int len; 65 int i, err; 66 67 if (s == &oxfw->tx_stream) { 68 formats = oxfw->tx_stream_formats; 69 dir = AVC_GENERAL_PLUG_DIR_OUT; 70 } else { 71 formats = oxfw->rx_stream_formats; 72 dir = AVC_GENERAL_PLUG_DIR_IN; 73 } 74 75 /* Seek stream format for requirements. */ 76 for (i = 0; i < SND_OXFW_STREAM_FORMAT_ENTRIES; i++) { 77 err = snd_oxfw_stream_parse_format(formats[i], &formation); 78 if (err < 0) 79 return err; 80 81 if ((formation.rate == rate) && (formation.pcm == pcm_channels)) 82 break; 83 } 84 if (i == SND_OXFW_STREAM_FORMAT_ENTRIES) 85 return -EINVAL; 86 87 /* If assumed, just change rate. */ 88 if (oxfw->assumed) 89 return set_rate(oxfw, rate); 90 91 /* Calculate format length. */ 92 len = 5 + formats[i][4] * 2; 93 94 err = avc_stream_set_format(oxfw->unit, dir, 0, formats[i], len); 95 if (err < 0) 96 return err; 97 98 /* Some requests just after changing format causes freezing. */ 99 msleep(100); 100 101 return 0; 102 } 103 104 static int start_stream(struct snd_oxfw *oxfw, struct amdtp_stream *stream) 105 { 106 struct cmp_connection *conn; 107 int err; 108 109 if (stream == &oxfw->rx_stream) 110 conn = &oxfw->in_conn; 111 else 112 conn = &oxfw->out_conn; 113 114 err = cmp_connection_establish(conn, 115 amdtp_stream_get_max_payload(stream)); 116 if (err < 0) 117 return err; 118 119 err = amdtp_stream_start(stream, conn->resources.channel, conn->speed); 120 if (err < 0) { 121 cmp_connection_break(conn); 122 return err; 123 } 124 125 // Wait first packet. 126 if (!amdtp_stream_wait_callback(stream, CALLBACK_TIMEOUT)) { 127 amdtp_stream_stop(stream); 128 cmp_connection_break(conn); 129 return -ETIMEDOUT; 130 } 131 132 return 0; 133 } 134 135 static int check_connection_used_by_others(struct snd_oxfw *oxfw, 136 struct amdtp_stream *stream) 137 { 138 struct cmp_connection *conn; 139 bool used; 140 int err; 141 142 if (stream == &oxfw->tx_stream) 143 conn = &oxfw->out_conn; 144 else 145 conn = &oxfw->in_conn; 146 147 err = cmp_connection_check_used(conn, &used); 148 if ((err >= 0) && used && !amdtp_stream_running(stream)) { 149 dev_err(&oxfw->unit->device, 150 "Connection established by others: %cPCR[%d]\n", 151 (conn->direction == CMP_OUTPUT) ? 'o' : 'i', 152 conn->pcr_index); 153 err = -EBUSY; 154 } 155 156 return err; 157 } 158 159 static int init_stream(struct snd_oxfw *oxfw, struct amdtp_stream *stream) 160 { 161 struct cmp_connection *conn; 162 enum cmp_direction c_dir; 163 enum amdtp_stream_direction s_dir; 164 int err; 165 166 if (stream == &oxfw->tx_stream) { 167 conn = &oxfw->out_conn; 168 c_dir = CMP_OUTPUT; 169 s_dir = AMDTP_IN_STREAM; 170 } else { 171 conn = &oxfw->in_conn; 172 c_dir = CMP_INPUT; 173 s_dir = AMDTP_OUT_STREAM; 174 } 175 176 err = cmp_connection_init(conn, oxfw->unit, c_dir, 0); 177 if (err < 0) 178 return err; 179 180 err = amdtp_am824_init(stream, oxfw->unit, s_dir, CIP_NONBLOCKING); 181 if (err < 0) { 182 cmp_connection_destroy(conn); 183 return err; 184 } 185 186 /* 187 * OXFW starts to transmit packets with non-zero dbc. 188 * OXFW postpone transferring packets till handling any asynchronous 189 * packets. As a result, next isochronous packet includes more data 190 * blocks than IEC 61883-6 defines. 191 */ 192 if (stream == &oxfw->tx_stream) { 193 oxfw->tx_stream.flags |= CIP_JUMBO_PAYLOAD; 194 if (oxfw->wrong_dbs) 195 oxfw->tx_stream.flags |= CIP_WRONG_DBS; 196 } 197 198 return 0; 199 } 200 201 static int keep_resources(struct snd_oxfw *oxfw, struct amdtp_stream *stream) 202 { 203 enum avc_general_plug_dir dir; 204 u8 **formats; 205 struct snd_oxfw_stream_formation formation; 206 int i; 207 int err; 208 209 if (stream == &oxfw->rx_stream) { 210 dir = AVC_GENERAL_PLUG_DIR_IN; 211 formats = oxfw->rx_stream_formats; 212 } else { 213 dir = AVC_GENERAL_PLUG_DIR_OUT; 214 formats = oxfw->tx_stream_formats; 215 } 216 217 err = snd_oxfw_stream_get_current_formation(oxfw, dir, &formation); 218 if (err < 0) 219 return err; 220 221 for (i = 0; i < SND_OXFW_STREAM_FORMAT_ENTRIES; i++) { 222 struct snd_oxfw_stream_formation fmt; 223 224 if (formats[i] == NULL) 225 break; 226 227 err = snd_oxfw_stream_parse_format(formats[i], &fmt); 228 if (err < 0) 229 return err; 230 231 if (fmt.rate == formation.rate && fmt.pcm == formation.pcm && 232 fmt.midi == formation.midi) 233 break; 234 } 235 if (i == SND_OXFW_STREAM_FORMAT_ENTRIES) 236 return -EINVAL; 237 238 // The stream should have one pcm channels at least. 239 if (formation.pcm == 0) 240 return -EINVAL; 241 242 return amdtp_am824_set_parameters(stream, formation.rate, formation.pcm, 243 formation.midi * 8, false); 244 } 245 246 int snd_oxfw_stream_reserve_duplex(struct snd_oxfw *oxfw, 247 struct amdtp_stream *stream, 248 unsigned int rate, unsigned int pcm_channels) 249 { 250 struct snd_oxfw_stream_formation formation; 251 enum avc_general_plug_dir dir; 252 int err; 253 254 // Considering JACK/FFADO streaming: 255 // TODO: This can be removed hwdep functionality becomes popular. 256 err = check_connection_used_by_others(oxfw, &oxfw->rx_stream); 257 if (err < 0) 258 return err; 259 if (oxfw->has_output) { 260 err = check_connection_used_by_others(oxfw, &oxfw->tx_stream); 261 if (err < 0) 262 return err; 263 } 264 265 if (stream == &oxfw->tx_stream) 266 dir = AVC_GENERAL_PLUG_DIR_OUT; 267 else 268 dir = AVC_GENERAL_PLUG_DIR_IN; 269 270 err = snd_oxfw_stream_get_current_formation(oxfw, dir, &formation); 271 if (err < 0) 272 return err; 273 if (rate == 0) { 274 rate = formation.rate; 275 pcm_channels = formation.pcm; 276 } 277 if (formation.rate != rate || formation.pcm != pcm_channels) { 278 amdtp_stream_stop(&oxfw->rx_stream); 279 cmp_connection_break(&oxfw->in_conn); 280 281 if (oxfw->has_output) { 282 amdtp_stream_stop(&oxfw->tx_stream); 283 cmp_connection_break(&oxfw->out_conn); 284 } 285 } 286 287 if (oxfw->substreams_count == 0 || 288 formation.rate != rate || formation.pcm != pcm_channels) { 289 err = set_stream_format(oxfw, stream, rate, pcm_channels); 290 if (err < 0) { 291 dev_err(&oxfw->unit->device, 292 "fail to set stream format: %d\n", err); 293 return err; 294 } 295 296 err = keep_resources(oxfw, &oxfw->rx_stream); 297 if (err < 0) 298 return err; 299 300 if (oxfw->has_output) { 301 err = keep_resources(oxfw, &oxfw->tx_stream); 302 if (err < 0) 303 return err; 304 } 305 } 306 307 return 0; 308 } 309 310 int snd_oxfw_stream_start_duplex(struct snd_oxfw *oxfw) 311 { 312 int err; 313 314 if (oxfw->substreams_count == 0) 315 return -EIO; 316 317 if (amdtp_streaming_error(&oxfw->rx_stream) || 318 amdtp_streaming_error(&oxfw->tx_stream)) { 319 amdtp_stream_stop(&oxfw->rx_stream); 320 cmp_connection_break(&oxfw->in_conn); 321 322 if (oxfw->has_output) { 323 amdtp_stream_stop(&oxfw->tx_stream); 324 cmp_connection_break(&oxfw->out_conn); 325 } 326 } 327 328 if (!amdtp_stream_running(&oxfw->rx_stream)) { 329 err = start_stream(oxfw, &oxfw->rx_stream); 330 if (err < 0) { 331 dev_err(&oxfw->unit->device, 332 "fail to start rx stream: %d\n", err); 333 goto error; 334 } 335 } 336 337 if (oxfw->has_output) { 338 if (!amdtp_stream_running(&oxfw->tx_stream)) { 339 err = start_stream(oxfw, &oxfw->tx_stream); 340 if (err < 0) { 341 dev_err(&oxfw->unit->device, 342 "fail to start tx stream: %d\n", err); 343 goto error; 344 } 345 } 346 } 347 348 return 0; 349 error: 350 amdtp_stream_stop(&oxfw->rx_stream); 351 cmp_connection_break(&oxfw->in_conn); 352 if (oxfw->has_output) { 353 amdtp_stream_stop(&oxfw->tx_stream); 354 cmp_connection_break(&oxfw->out_conn); 355 } 356 return err; 357 } 358 359 void snd_oxfw_stream_stop_duplex(struct snd_oxfw *oxfw) 360 { 361 if (oxfw->substreams_count == 0) { 362 amdtp_stream_stop(&oxfw->rx_stream); 363 cmp_connection_break(&oxfw->in_conn); 364 365 if (oxfw->has_output) { 366 amdtp_stream_stop(&oxfw->tx_stream); 367 cmp_connection_break(&oxfw->out_conn); 368 } 369 } 370 } 371 372 static void destroy_stream(struct snd_oxfw *oxfw, struct amdtp_stream *stream) 373 { 374 struct cmp_connection *conn; 375 376 if (stream == &oxfw->tx_stream) 377 conn = &oxfw->out_conn; 378 else 379 conn = &oxfw->in_conn; 380 381 amdtp_stream_destroy(stream); 382 cmp_connection_destroy(conn); 383 } 384 385 int snd_oxfw_stream_init_duplex(struct snd_oxfw *oxfw) 386 { 387 int err; 388 389 err = init_stream(oxfw, &oxfw->rx_stream); 390 if (err < 0) 391 return err; 392 393 if (oxfw->has_output) { 394 err = init_stream(oxfw, &oxfw->tx_stream); 395 if (err < 0) { 396 destroy_stream(oxfw, &oxfw->rx_stream); 397 return err; 398 } 399 } 400 401 return 0; 402 } 403 404 // This function should be called before starting the stream or after stopping 405 // the streams. 406 void snd_oxfw_stream_destroy_duplex(struct snd_oxfw *oxfw) 407 { 408 destroy_stream(oxfw, &oxfw->rx_stream); 409 410 if (oxfw->has_output) 411 destroy_stream(oxfw, &oxfw->tx_stream); 412 } 413 414 void snd_oxfw_stream_update_duplex(struct snd_oxfw *oxfw) 415 { 416 amdtp_stream_stop(&oxfw->rx_stream); 417 cmp_connection_break(&oxfw->in_conn); 418 419 amdtp_stream_pcm_abort(&oxfw->rx_stream); 420 421 if (oxfw->has_output) { 422 amdtp_stream_stop(&oxfw->tx_stream); 423 cmp_connection_break(&oxfw->out_conn); 424 425 amdtp_stream_pcm_abort(&oxfw->tx_stream); 426 } 427 } 428 429 int snd_oxfw_stream_get_current_formation(struct snd_oxfw *oxfw, 430 enum avc_general_plug_dir dir, 431 struct snd_oxfw_stream_formation *formation) 432 { 433 u8 *format; 434 unsigned int len; 435 int err; 436 437 len = AVC_GENERIC_FRAME_MAXIMUM_BYTES; 438 format = kmalloc(len, GFP_KERNEL); 439 if (format == NULL) 440 return -ENOMEM; 441 442 err = avc_stream_get_format_single(oxfw->unit, dir, 0, format, &len); 443 if (err < 0) 444 goto end; 445 if (len < 3) { 446 err = -EIO; 447 goto end; 448 } 449 450 err = snd_oxfw_stream_parse_format(format, formation); 451 end: 452 kfree(format); 453 return err; 454 } 455 456 /* 457 * See Table 6.16 - AM824 Stream Format 458 * Figure 6.19 - format_information field for AM824 Compound 459 * in AV/C Stream Format Information Specification 1.1 (Apr 2005, 1394TA) 460 * Also 'Clause 12 AM824 sequence adaption layers' in IEC 61883-6:2005 461 */ 462 int snd_oxfw_stream_parse_format(u8 *format, 463 struct snd_oxfw_stream_formation *formation) 464 { 465 unsigned int i, e, channels, type; 466 467 memset(formation, 0, sizeof(struct snd_oxfw_stream_formation)); 468 469 /* 470 * this module can support a hierarchy combination that: 471 * Root: Audio and Music (0x90) 472 * Level 1: AM824 Compound (0x40) 473 */ 474 if ((format[0] != 0x90) || (format[1] != 0x40)) 475 return -ENOSYS; 476 477 /* check the sampling rate */ 478 for (i = 0; i < ARRAY_SIZE(avc_stream_rate_table); i++) { 479 if (format[2] == avc_stream_rate_table[i]) 480 break; 481 } 482 if (i == ARRAY_SIZE(avc_stream_rate_table)) 483 return -ENOSYS; 484 485 formation->rate = oxfw_rate_table[i]; 486 487 for (e = 0; e < format[4]; e++) { 488 channels = format[5 + e * 2]; 489 type = format[6 + e * 2]; 490 491 switch (type) { 492 /* IEC 60958 Conformant, currently handled as MBLA */ 493 case 0x00: 494 /* Multi Bit Linear Audio (Raw) */ 495 case 0x06: 496 formation->pcm += channels; 497 break; 498 /* MIDI Conformant */ 499 case 0x0d: 500 formation->midi = channels; 501 break; 502 /* IEC 61937-3 to 7 */ 503 case 0x01: 504 case 0x02: 505 case 0x03: 506 case 0x04: 507 case 0x05: 508 /* Multi Bit Linear Audio */ 509 case 0x07: /* DVD-Audio */ 510 case 0x0c: /* High Precision */ 511 /* One Bit Audio */ 512 case 0x08: /* (Plain) Raw */ 513 case 0x09: /* (Plain) SACD */ 514 case 0x0a: /* (Encoded) Raw */ 515 case 0x0b: /* (Encoded) SACD */ 516 /* SMPTE Time-Code conformant */ 517 case 0x0e: 518 /* Sample Count */ 519 case 0x0f: 520 /* Anciliary Data */ 521 case 0x10: 522 /* Synchronization Stream (Stereo Raw audio) */ 523 case 0x40: 524 /* Don't care */ 525 case 0xff: 526 default: 527 return -ENOSYS; /* not supported */ 528 } 529 } 530 531 if (formation->pcm > AM824_MAX_CHANNELS_FOR_PCM || 532 formation->midi > AM824_MAX_CHANNELS_FOR_MIDI) 533 return -ENOSYS; 534 535 return 0; 536 } 537 538 static int 539 assume_stream_formats(struct snd_oxfw *oxfw, enum avc_general_plug_dir dir, 540 unsigned int pid, u8 *buf, unsigned int *len, 541 u8 **formats) 542 { 543 struct snd_oxfw_stream_formation formation; 544 unsigned int i, eid; 545 int err; 546 547 /* get format at current sampling rate */ 548 err = avc_stream_get_format_single(oxfw->unit, dir, pid, buf, len); 549 if (err < 0) { 550 dev_err(&oxfw->unit->device, 551 "fail to get current stream format for isoc %s plug %d:%d\n", 552 (dir == AVC_GENERAL_PLUG_DIR_IN) ? "in" : "out", 553 pid, err); 554 goto end; 555 } 556 557 /* parse and set stream format */ 558 eid = 0; 559 err = snd_oxfw_stream_parse_format(buf, &formation); 560 if (err < 0) 561 goto end; 562 563 formats[eid] = devm_kmemdup(&oxfw->card->card_dev, buf, *len, 564 GFP_KERNEL); 565 if (!formats[eid]) { 566 err = -ENOMEM; 567 goto end; 568 } 569 570 /* apply the format for each available sampling rate */ 571 for (i = 0; i < ARRAY_SIZE(oxfw_rate_table); i++) { 572 if (formation.rate == oxfw_rate_table[i]) 573 continue; 574 575 err = avc_general_inquiry_sig_fmt(oxfw->unit, 576 oxfw_rate_table[i], 577 dir, pid); 578 if (err < 0) 579 continue; 580 581 eid++; 582 formats[eid] = devm_kmemdup(&oxfw->card->card_dev, buf, *len, 583 GFP_KERNEL); 584 if (formats[eid] == NULL) { 585 err = -ENOMEM; 586 goto end; 587 } 588 formats[eid][2] = avc_stream_rate_table[i]; 589 } 590 591 err = 0; 592 oxfw->assumed = true; 593 end: 594 return err; 595 } 596 597 static int fill_stream_formats(struct snd_oxfw *oxfw, 598 enum avc_general_plug_dir dir, 599 unsigned short pid) 600 { 601 u8 *buf, **formats; 602 unsigned int len, eid = 0; 603 struct snd_oxfw_stream_formation dummy; 604 int err; 605 606 buf = kmalloc(AVC_GENERIC_FRAME_MAXIMUM_BYTES, GFP_KERNEL); 607 if (buf == NULL) 608 return -ENOMEM; 609 610 if (dir == AVC_GENERAL_PLUG_DIR_OUT) 611 formats = oxfw->tx_stream_formats; 612 else 613 formats = oxfw->rx_stream_formats; 614 615 /* get first entry */ 616 len = AVC_GENERIC_FRAME_MAXIMUM_BYTES; 617 err = avc_stream_get_format_list(oxfw->unit, dir, 0, buf, &len, 0); 618 if (err == -ENOSYS) { 619 /* LIST subfunction is not implemented */ 620 len = AVC_GENERIC_FRAME_MAXIMUM_BYTES; 621 err = assume_stream_formats(oxfw, dir, pid, buf, &len, 622 formats); 623 goto end; 624 } else if (err < 0) { 625 dev_err(&oxfw->unit->device, 626 "fail to get stream format %d for isoc %s plug %d:%d\n", 627 eid, (dir == AVC_GENERAL_PLUG_DIR_IN) ? "in" : "out", 628 pid, err); 629 goto end; 630 } 631 632 /* LIST subfunction is implemented */ 633 while (eid < SND_OXFW_STREAM_FORMAT_ENTRIES) { 634 /* The format is too short. */ 635 if (len < 3) { 636 err = -EIO; 637 break; 638 } 639 640 /* parse and set stream format */ 641 err = snd_oxfw_stream_parse_format(buf, &dummy); 642 if (err < 0) 643 break; 644 645 formats[eid] = devm_kmemdup(&oxfw->card->card_dev, buf, len, 646 GFP_KERNEL); 647 if (!formats[eid]) { 648 err = -ENOMEM; 649 break; 650 } 651 652 /* get next entry */ 653 len = AVC_GENERIC_FRAME_MAXIMUM_BYTES; 654 err = avc_stream_get_format_list(oxfw->unit, dir, 0, 655 buf, &len, ++eid); 656 /* No entries remained. */ 657 if (err == -EINVAL) { 658 err = 0; 659 break; 660 } else if (err < 0) { 661 dev_err(&oxfw->unit->device, 662 "fail to get stream format %d for isoc %s plug %d:%d\n", 663 eid, (dir == AVC_GENERAL_PLUG_DIR_IN) ? "in" : 664 "out", 665 pid, err); 666 break; 667 } 668 } 669 end: 670 kfree(buf); 671 return err; 672 } 673 674 int snd_oxfw_stream_discover(struct snd_oxfw *oxfw) 675 { 676 u8 plugs[AVC_PLUG_INFO_BUF_BYTES]; 677 struct snd_oxfw_stream_formation formation; 678 u8 *format; 679 unsigned int i; 680 int err; 681 682 /* the number of plugs for isoc in/out, ext in/out */ 683 err = avc_general_get_plug_info(oxfw->unit, 0x1f, 0x07, 0x00, plugs); 684 if (err < 0) { 685 dev_err(&oxfw->unit->device, 686 "fail to get info for isoc/external in/out plugs: %d\n", 687 err); 688 goto end; 689 } else if ((plugs[0] == 0) && (plugs[1] == 0)) { 690 err = -ENOSYS; 691 goto end; 692 } 693 694 /* use oPCR[0] if exists */ 695 if (plugs[1] > 0) { 696 err = fill_stream_formats(oxfw, AVC_GENERAL_PLUG_DIR_OUT, 0); 697 if (err < 0) 698 goto end; 699 700 for (i = 0; i < SND_OXFW_STREAM_FORMAT_ENTRIES; i++) { 701 format = oxfw->tx_stream_formats[i]; 702 if (format == NULL) 703 continue; 704 err = snd_oxfw_stream_parse_format(format, &formation); 705 if (err < 0) 706 continue; 707 708 /* Add one MIDI port. */ 709 if (formation.midi > 0) 710 oxfw->midi_input_ports = 1; 711 } 712 713 oxfw->has_output = true; 714 } 715 716 /* use iPCR[0] if exists */ 717 if (plugs[0] > 0) { 718 err = fill_stream_formats(oxfw, AVC_GENERAL_PLUG_DIR_IN, 0); 719 if (err < 0) 720 goto end; 721 722 for (i = 0; i < SND_OXFW_STREAM_FORMAT_ENTRIES; i++) { 723 format = oxfw->rx_stream_formats[i]; 724 if (format == NULL) 725 continue; 726 err = snd_oxfw_stream_parse_format(format, &formation); 727 if (err < 0) 728 continue; 729 730 /* Add one MIDI port. */ 731 if (formation.midi > 0) 732 oxfw->midi_output_ports = 1; 733 } 734 } 735 end: 736 return err; 737 } 738 739 void snd_oxfw_stream_lock_changed(struct snd_oxfw *oxfw) 740 { 741 oxfw->dev_lock_changed = true; 742 wake_up(&oxfw->hwdep_wait); 743 } 744 745 int snd_oxfw_stream_lock_try(struct snd_oxfw *oxfw) 746 { 747 int err; 748 749 spin_lock_irq(&oxfw->lock); 750 751 /* user land lock this */ 752 if (oxfw->dev_lock_count < 0) { 753 err = -EBUSY; 754 goto end; 755 } 756 757 /* this is the first time */ 758 if (oxfw->dev_lock_count++ == 0) 759 snd_oxfw_stream_lock_changed(oxfw); 760 err = 0; 761 end: 762 spin_unlock_irq(&oxfw->lock); 763 return err; 764 } 765 766 void snd_oxfw_stream_lock_release(struct snd_oxfw *oxfw) 767 { 768 spin_lock_irq(&oxfw->lock); 769 770 if (WARN_ON(oxfw->dev_lock_count <= 0)) 771 goto end; 772 if (--oxfw->dev_lock_count == 0) 773 snd_oxfw_stream_lock_changed(oxfw); 774 end: 775 spin_unlock_irq(&oxfw->lock); 776 } 777