sound/firewire/dice/dice-stream.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * dice_stream.c - a part of driver for DICE based devices
   4  *
   5  * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
   6  * Copyright (c) 2014 Takashi Sakamoto <o-takashi@sakamocchi.jp>
   7  */
   8
   9 #include "dice.h"
  10
  11 #define READY_TIMEOUT_MS        200
  12 #define NOTIFICATION_TIMEOUT_MS 100
  13
  14 struct reg_params {
  15         unsigned int count;
  16         unsigned int size;
  17 };
  18
  19 const unsigned int snd_dice_rates[SND_DICE_RATES_COUNT] = {
  20         /* mode 0 */
  21         [0] =  32000,
  22         [1] =  44100,
  23         [2] =  48000,
  24         /* mode 1 */
  25         [3] =  88200,
  26         [4] =  96000,
  27         /* mode 2 */
  28         [5] = 176400,
  29         [6] = 192000,
  30 };
  31
  32 int snd_dice_stream_get_rate_mode(struct snd_dice *dice, unsigned int rate,
  33                                   enum snd_dice_rate_mode *mode)
  34 {
  35         /* Corresponding to each entry in snd_dice_rates. */
  36         static const enum snd_dice_rate_mode modes[] = {
  37                 [0] = SND_DICE_RATE_MODE_LOW,
  38                 [1] = SND_DICE_RATE_MODE_LOW,
  39                 [2] = SND_DICE_RATE_MODE_LOW,
  40                 [3] = SND_DICE_RATE_MODE_MIDDLE,
  41                 [4] = SND_DICE_RATE_MODE_MIDDLE,
  42                 [5] = SND_DICE_RATE_MODE_HIGH,
  43                 [6] = SND_DICE_RATE_MODE_HIGH,
  44         };
  45         int i;
  46
  47         for (i = 0; i < ARRAY_SIZE(snd_dice_rates); i++) {
  48                 if (!(dice->clock_caps & BIT(i)))
  49                         continue;
  50                 if (snd_dice_rates[i] != rate)
  51                         continue;
  52
  53                 *mode = modes[i];
  54                 return 0;
  55         }
  56
  57         return -EINVAL;
  58 }
  59
  60 static int select_clock(struct snd_dice *dice, unsigned int rate)
  61 {
  62         __be32 reg, new;
  63         u32 data;
  64         int i;
  65         int err;
  66
  67         err = snd_dice_transaction_read_global(dice, GLOBAL_CLOCK_SELECT,
  68                                                &reg, sizeof(reg));
  69         if (err < 0)
  70                 return err;
  71
  72         data = be32_to_cpu(reg);
  73
  74         data &= ~CLOCK_RATE_MASK;
  75         for (i = 0; i < ARRAY_SIZE(snd_dice_rates); ++i) {
  76                 if (snd_dice_rates[i] == rate)
  77                         break;
  78         }
  79         if (i == ARRAY_SIZE(snd_dice_rates))
  80                 return -EINVAL;
  81         data |= i << CLOCK_RATE_SHIFT;
  82
  83         if (completion_done(&dice->clock_accepted))
  84                 reinit_completion(&dice->clock_accepted);
  85
  86         new = cpu_to_be32(data);
  87         err = snd_dice_transaction_write_global(dice, GLOBAL_CLOCK_SELECT,
  88                                                 &new, sizeof(new));
  89         if (err < 0)
  90                 return err;
  91
  92         if (wait_for_completion_timeout(&dice->clock_accepted,
  93                         msecs_to_jiffies(NOTIFICATION_TIMEOUT_MS)) == 0) {
  94                 if (reg != new)
  95                         return -ETIMEDOUT;
  96         }
  97
  98         return 0;
  99 }
 100
 101 static int get_register_params(struct snd_dice *dice,
 102                                struct reg_params *tx_params,
 103                                struct reg_params *rx_params)
 104 {
 105         __be32 reg[2];
 106         int err;
 107
 108         err = snd_dice_transaction_read_tx(dice, TX_NUMBER, reg, sizeof(reg));
 109         if (err < 0)
 110                 return err;
 111         tx_params->count =
 112                         min_t(unsigned int, be32_to_cpu(reg[0]), MAX_STREAMS);
 113         tx_params->size = be32_to_cpu(reg[1]) * 4;
 114
 115         err = snd_dice_transaction_read_rx(dice, RX_NUMBER, reg, sizeof(reg));
 116         if (err < 0)
 117                 return err;
 118         rx_params->count =
 119                         min_t(unsigned int, be32_to_cpu(reg[0]), MAX_STREAMS);
 120         rx_params->size = be32_to_cpu(reg[1]) * 4;
 121
 122         return 0;
 123 }
 124
 125 static void release_resources(struct snd_dice *dice)
 126 {
 127         int i;
 128
 129         for (i = 0; i < MAX_STREAMS; ++i) {
 130                 fw_iso_resources_free(&dice->tx_resources[i]);
 131                 fw_iso_resources_free(&dice->rx_resources[i]);
 132         }
 133 }
 134
 135 static void stop_streams(struct snd_dice *dice, enum amdtp_stream_direction dir,
 136                          struct reg_params *params)
 137 {
 138         __be32 reg;
 139         unsigned int i;
 140
 141         for (i = 0; i < params->count; i++) {
 142                 reg = cpu_to_be32((u32)-1);
 143                 if (dir == AMDTP_IN_STREAM) {
 144                         snd_dice_transaction_write_tx(dice,
 145                                         params->size * i + TX_ISOCHRONOUS,
 146                                         &reg, sizeof(reg));
 147                 } else {
 148                         snd_dice_transaction_write_rx(dice,
 149                                         params->size * i + RX_ISOCHRONOUS,
 150                                         &reg, sizeof(reg));
 151                 }
 152         }
 153 }
 154
 155 static int keep_resources(struct snd_dice *dice, struct amdtp_stream *stream,
 156                           struct fw_iso_resources *resources, unsigned int rate,
 157                           unsigned int pcm_chs, unsigned int midi_ports)
 158 {
 159         bool double_pcm_frames;
 160         unsigned int i;
 161         int err;
 162
 163         // At 176.4/192.0 kHz, Dice has a quirk to transfer two PCM frames in
 164         // one data block of AMDTP packet. Thus sampling transfer frequency is
 165         // a half of PCM sampling frequency, i.e. PCM frames at 192.0 kHz are
 166         // transferred on AMDTP packets at 96 kHz. Two successive samples of a
 167         // channel are stored consecutively in the packet. This quirk is called
 168         // as 'Dual Wire'.
 169         // For this quirk, blocking mode is required and PCM buffer size should
 170         // be aligned to SYT_INTERVAL.
 171         double_pcm_frames = (rate > 96000 && !dice->disable_double_pcm_frames);
 172         if (double_pcm_frames) {
 173                 rate /= 2;
 174                 pcm_chs *= 2;
 175         }
 176
 177         err = amdtp_am824_set_parameters(stream, rate, pcm_chs, midi_ports,
 178                                          double_pcm_frames);
 179         if (err < 0)
 180                 return err;
 181
 182         if (double_pcm_frames) {
 183                 pcm_chs /= 2;
 184
 185                 for (i = 0; i < pcm_chs; i++) {
 186                         amdtp_am824_set_pcm_position(stream, i, i * 2);
 187                         amdtp_am824_set_pcm_position(stream, i + pcm_chs,
 188                                                      i * 2 + 1);
 189                 }
 190         }
 191
 192         return fw_iso_resources_allocate(resources,
 193                                 amdtp_stream_get_max_payload(stream),
 194                                 fw_parent_device(dice->unit)->max_speed);
 195 }
 196
 197 static int keep_dual_resources(struct snd_dice *dice, unsigned int rate,
 198                                enum amdtp_stream_direction dir,
 199                                struct reg_params *params)
 200 {
 201         enum snd_dice_rate_mode mode;
 202         int i;
 203         int err;
 204
 205         err = snd_dice_stream_get_rate_mode(dice, rate, &mode);
 206         if (err < 0)
 207                 return err;
 208
 209         for (i = 0; i < params->count; ++i) {
 210                 __be32 reg[2];
 211                 struct amdtp_stream *stream;
 212                 struct fw_iso_resources *resources;
 213                 unsigned int pcm_cache;
 214                 unsigned int pcm_chs;
 215                 unsigned int midi_ports;
 216
 217                 if (dir == AMDTP_IN_STREAM) {
 218                         stream = &dice->tx_stream[i];
 219                         resources = &dice->tx_resources[i];
 220
 221                         pcm_cache = dice->tx_pcm_chs[i][mode];
 222                         err = snd_dice_transaction_read_tx(dice,
 223                                         params->size * i + TX_NUMBER_AUDIO,
 224                                         reg, sizeof(reg));
 225                 } else {
 226                         stream = &dice->rx_stream[i];
 227                         resources = &dice->rx_resources[i];
 228
 229                         pcm_cache = dice->rx_pcm_chs[i][mode];
 230                         err = snd_dice_transaction_read_rx(dice,
 231                                         params->size * i + RX_NUMBER_AUDIO,
 232                                         reg, sizeof(reg));
 233                 }
 234                 if (err < 0)
 235                         return err;
 236                 pcm_chs = be32_to_cpu(reg[0]);
 237                 midi_ports = be32_to_cpu(reg[1]);
 238
 239                 // These are important for developer of this driver.
 240                 if (pcm_chs != pcm_cache) {
 241                         dev_info(&dice->unit->device,
 242                                  "cache mismatch: pcm: %u:%u, midi: %u\n",
 243                                  pcm_chs, pcm_cache, midi_ports);
 244                         return -EPROTO;
 245                 }
 246
 247                 err = keep_resources(dice, stream, resources, rate, pcm_chs,
 248                                      midi_ports);
 249                 if (err < 0)
 250                         return err;
 251         }
 252
 253         return 0;
 254 }
 255
 256 static void finish_session(struct snd_dice *dice, struct reg_params *tx_params,
 257                            struct reg_params *rx_params)
 258 {
 259         stop_streams(dice, AMDTP_IN_STREAM, tx_params);
 260         stop_streams(dice, AMDTP_OUT_STREAM, rx_params);
 261
 262         snd_dice_transaction_clear_enable(dice);
 263 }
 264
 265 int snd_dice_stream_reserve_duplex(struct snd_dice *dice, unsigned int rate,
 266                                    unsigned int events_per_period,
 267                                    unsigned int events_per_buffer)
 268 {
 269         unsigned int curr_rate;
 270         int err;
 271
 272         // Check sampling transmission frequency.
 273         err = snd_dice_transaction_get_rate(dice, &curr_rate);
 274         if (err < 0)
 275                 return err;
 276         if (rate == 0)
 277                 rate = curr_rate;
 278
 279         if (dice->substreams_counter == 0 || curr_rate != rate) {
 280                 struct reg_params tx_params, rx_params;
 281
 282                 amdtp_domain_stop(&dice->domain);
 283
 284                 err = get_register_params(dice, &tx_params, &rx_params);
 285                 if (err < 0)
 286                         return err;
 287                 finish_session(dice, &tx_params, &rx_params);
 288
 289                 release_resources(dice);
 290
 291                 // Just after owning the unit (GLOBAL_OWNER), the unit can
 292                 // return invalid stream formats. Selecting clock parameters
 293                 // have an effect for the unit to refine it.
 294                 err = select_clock(dice, rate);
 295                 if (err < 0)
 296                         return err;
 297
 298                 // After changing sampling transfer frequency, the value of
 299                 // register can be changed.
 300                 err = get_register_params(dice, &tx_params, &rx_params);
 301                 if (err < 0)
 302                         return err;
 303
 304                 err = keep_dual_resources(dice, rate, AMDTP_IN_STREAM,
 305                                           &tx_params);
 306                 if (err < 0)
 307                         goto error;
 308
 309                 err = keep_dual_resources(dice, rate, AMDTP_OUT_STREAM,
 310                                           &rx_params);
 311                 if (err < 0)
 312                         goto error;
 313
 314                 err = amdtp_domain_set_events_per_period(&dice->domain,
 315                                         events_per_period, events_per_buffer);
 316                 if (err < 0)
 317                         goto error;
 318         }
 319
 320         return 0;
 321 error:
 322         release_resources(dice);
 323         return err;
 324 }
 325
 326 static int start_streams(struct snd_dice *dice, enum amdtp_stream_direction dir,
 327                          unsigned int rate, struct reg_params *params)
 328 {
 329         unsigned int max_speed = fw_parent_device(dice->unit)->max_speed;
 330         int i;
 331         int err;
 332
 333         for (i = 0; i < params->count; i++) {
 334                 struct amdtp_stream *stream;
 335                 struct fw_iso_resources *resources;
 336                 __be32 reg;
 337
 338                 if (dir == AMDTP_IN_STREAM) {
 339                         stream = dice->tx_stream + i;
 340                         resources = dice->tx_resources + i;
 341                 } else {
 342                         stream = dice->rx_stream + i;
 343                         resources = dice->rx_resources + i;
 344                 }
 345
 346                 reg = cpu_to_be32(resources->channel);
 347                 if (dir == AMDTP_IN_STREAM) {
 348                         err = snd_dice_transaction_write_tx(dice,
 349                                         params->size * i + TX_ISOCHRONOUS,
 350                                         &reg, sizeof(reg));
 351                 } else {
 352                         err = snd_dice_transaction_write_rx(dice,
 353                                         params->size * i + RX_ISOCHRONOUS,
 354                                         &reg, sizeof(reg));
 355                 }
 356                 if (err < 0)
 357                         return err;
 358
 359                 if (dir == AMDTP_IN_STREAM) {
 360                         reg = cpu_to_be32(max_speed);
 361                         err = snd_dice_transaction_write_tx(dice,
 362                                         params->size * i + TX_SPEED,
 363                                         &reg, sizeof(reg));
 364                         if (err < 0)
 365                                 return err;
 366                 }
 367
 368                 err = amdtp_domain_add_stream(&dice->domain, stream,
 369                                               resources->channel, max_speed);
 370                 if (err < 0)
 371                         return err;
 372         }
 373
 374         return 0;
 375 }
 376
 377 /*
 378  * MEMO: After this function, there're two states of streams:
 379  *  - None streams are running.
 380  *  - All streams are running.
 381  */
 382 int snd_dice_stream_start_duplex(struct snd_dice *dice)
 383 {
 384         unsigned int generation = dice->rx_resources[0].generation;
 385         struct reg_params tx_params, rx_params;
 386         unsigned int i;
 387         unsigned int rate;
 388         enum snd_dice_rate_mode mode;
 389         int err;
 390
 391         if (dice->substreams_counter == 0)
 392                 return -EIO;
 393
 394         err = get_register_params(dice, &tx_params, &rx_params);
 395         if (err < 0)
 396                 return err;
 397
 398         // Check error of packet streaming.
 399         for (i = 0; i < MAX_STREAMS; ++i) {
 400                 if (amdtp_streaming_error(&dice->tx_stream[i]) ||
 401                     amdtp_streaming_error(&dice->rx_stream[i])) {
 402                         amdtp_domain_stop(&dice->domain);
 403                         finish_session(dice, &tx_params, &rx_params);
 404                         break;
 405                 }
 406         }
 407
 408         if (generation != fw_parent_device(dice->unit)->card->generation) {
 409                 for (i = 0; i < MAX_STREAMS; ++i) {
 410                         if (i < tx_params.count)
 411                                 fw_iso_resources_update(dice->tx_resources + i);
 412                         if (i < rx_params.count)
 413                                 fw_iso_resources_update(dice->rx_resources + i);
 414                 }
 415         }
 416
 417         // Check required streams are running or not.
 418         err = snd_dice_transaction_get_rate(dice, &rate);
 419         if (err < 0)
 420                 return err;
 421         err = snd_dice_stream_get_rate_mode(dice, rate, &mode);
 422         if (err < 0)
 423                 return err;
 424         for (i = 0; i < MAX_STREAMS; ++i) {
 425                 if (dice->tx_pcm_chs[i][mode] > 0 &&
 426                     !amdtp_stream_running(&dice->tx_stream[i]))
 427                         break;
 428                 if (dice->rx_pcm_chs[i][mode] > 0 &&
 429                     !amdtp_stream_running(&dice->rx_stream[i]))
 430                         break;
 431         }
 432         if (i < MAX_STREAMS) {
 433                 // Start both streams.
 434                 err = start_streams(dice, AMDTP_IN_STREAM, rate, &tx_params);
 435                 if (err < 0)
 436                         goto error;
 437
 438                 err = start_streams(dice, AMDTP_OUT_STREAM, rate, &rx_params);
 439                 if (err < 0)
 440                         goto error;
 441
 442                 err = snd_dice_transaction_set_enable(dice);
 443                 if (err < 0) {
 444                         dev_err(&dice->unit->device,
 445                                 "fail to enable interface\n");
 446                         goto error;
 447                 }
 448
 449                 // MEMO: The device immediately starts packet transmission when enabled. Some
 450                 // devices are strictly to generate any discontinuity in the sequence of tx packet
 451                 // when they receives invalid sequence of presentation time in CIP header. The
 452                 // sequence replay for media clock recovery can suppress the behaviour.
 453                 err = amdtp_domain_start(&dice->domain, 0, true, false);
 454                 if (err < 0)
 455                         goto error;
 456
 457                 if (!amdtp_domain_wait_ready(&dice->domain, READY_TIMEOUT_MS)) {
 458                         err = -ETIMEDOUT;
 459                         goto error;
 460                 }
 461         }
 462
 463         return 0;
 464 error:
 465         amdtp_domain_stop(&dice->domain);
 466         finish_session(dice, &tx_params, &rx_params);
 467         return err;
 468 }
 469
 470 /*
 471  * MEMO: After this function, there're two states of streams:
 472  *  - None streams are running.
 473  *  - All streams are running.
 474  */
 475 void snd_dice_stream_stop_duplex(struct snd_dice *dice)
 476 {
 477         struct reg_params tx_params, rx_params;
 478
 479         if (dice->substreams_counter == 0) {
 480                 if (get_register_params(dice, &tx_params, &rx_params) >= 0)
 481                         finish_session(dice, &tx_params, &rx_params);
 482
 483                 amdtp_domain_stop(&dice->domain);
 484                 release_resources(dice);
 485         }
 486 }
 487
 488 static int init_stream(struct snd_dice *dice, enum amdtp_stream_direction dir,
 489                        unsigned int index)
 490 {
 491         struct amdtp_stream *stream;
 492         struct fw_iso_resources *resources;
 493         int err;
 494
 495         if (dir == AMDTP_IN_STREAM) {
 496                 stream = &dice->tx_stream[index];
 497                 resources = &dice->tx_resources[index];
 498         } else {
 499                 stream = &dice->rx_stream[index];
 500                 resources = &dice->rx_resources[index];
 501         }
 502
 503         err = fw_iso_resources_init(resources, dice->unit);
 504         if (err < 0)
 505                 goto end;
 506         resources->channels_mask = 0x00000000ffffffffuLL;
 507
 508         err = amdtp_am824_init(stream, dice->unit, dir, CIP_BLOCKING);
 509         if (err < 0) {
 510                 amdtp_stream_destroy(stream);
 511                 fw_iso_resources_destroy(resources);
 512         }
 513 end:
 514         return err;
 515 }
 516
 517 /*
 518  * This function should be called before starting streams or after stopping
 519  * streams.
 520  */
 521 static void destroy_stream(struct snd_dice *dice,
 522                            enum amdtp_stream_direction dir,
 523                            unsigned int index)
 524 {
 525         struct amdtp_stream *stream;
 526         struct fw_iso_resources *resources;
 527
 528         if (dir == AMDTP_IN_STREAM) {
 529                 stream = &dice->tx_stream[index];
 530                 resources = &dice->tx_resources[index];
 531         } else {
 532                 stream = &dice->rx_stream[index];
 533                 resources = &dice->rx_resources[index];
 534         }
 535
 536         amdtp_stream_destroy(stream);
 537         fw_iso_resources_destroy(resources);
 538 }
 539
 540 int snd_dice_stream_init_duplex(struct snd_dice *dice)
 541 {
 542         int i, err;
 543
 544         for (i = 0; i < MAX_STREAMS; i++) {
 545                 err = init_stream(dice, AMDTP_IN_STREAM, i);
 546                 if (err < 0) {
 547                         for (; i >= 0; i--)
 548                                 destroy_stream(dice, AMDTP_IN_STREAM, i);
 549                         goto end;
 550                 }
 551         }
 552
 553         for (i = 0; i < MAX_STREAMS; i++) {
 554                 err = init_stream(dice, AMDTP_OUT_STREAM, i);
 555                 if (err < 0) {
 556                         for (; i >= 0; i--)
 557                                 destroy_stream(dice, AMDTP_OUT_STREAM, i);
 558                         for (i = 0; i < MAX_STREAMS; i++)
 559                                 destroy_stream(dice, AMDTP_IN_STREAM, i);
 560                         goto end;
 561                 }
 562         }
 563
 564         err = amdtp_domain_init(&dice->domain);
 565         if (err < 0) {
 566                 for (i = 0; i < MAX_STREAMS; ++i) {
 567                         destroy_stream(dice, AMDTP_OUT_STREAM, i);
 568                         destroy_stream(dice, AMDTP_IN_STREAM, i);
 569                 }
 570         }
 571 end:
 572         return err;
 573 }
 574
 575 void snd_dice_stream_destroy_duplex(struct snd_dice *dice)
 576 {
 577         unsigned int i;
 578
 579         for (i = 0; i < MAX_STREAMS; i++) {
 580                 destroy_stream(dice, AMDTP_IN_STREAM, i);
 581                 destroy_stream(dice, AMDTP_OUT_STREAM, i);
 582         }
 583
 584         amdtp_domain_destroy(&dice->domain);
 585 }
 586
 587 void snd_dice_stream_update_duplex(struct snd_dice *dice)
 588 {
 589         struct reg_params tx_params, rx_params;
 590
 591         /*
 592          * On a bus reset, the DICE firmware disables streaming and then goes
 593          * off contemplating its own navel for hundreds of milliseconds before
 594          * it can react to any of our attempts to reenable streaming.  This
 595          * means that we lose synchronization anyway, so we force our streams
 596          * to stop so that the application can restart them in an orderly
 597          * manner.
 598          */
 599         dice->global_enabled = false;
 600
 601         if (get_register_params(dice, &tx_params, &rx_params) == 0) {
 602                 amdtp_domain_stop(&dice->domain);
 603
 604                 stop_streams(dice, AMDTP_IN_STREAM, &tx_params);
 605                 stop_streams(dice, AMDTP_OUT_STREAM, &rx_params);
 606         }
 607 }
 608
 609 int snd_dice_stream_detect_current_formats(struct snd_dice *dice)
 610 {
 611         unsigned int rate;
 612         enum snd_dice_rate_mode mode;
 613         __be32 reg[2];
 614         struct reg_params tx_params, rx_params;
 615         int i;
 616         int err;
 617
 618         /* If extended protocol is available, detect detail spec. */
 619         err = snd_dice_detect_extension_formats(dice);
 620         if (err >= 0)
 621                 return err;
 622
 623         /*
 624          * Available stream format is restricted at current mode of sampling
 625          * clock.
 626          */
 627         err = snd_dice_transaction_get_rate(dice, &rate);
 628         if (err < 0)
 629                 return err;
 630
 631         err = snd_dice_stream_get_rate_mode(dice, rate, &mode);
 632         if (err < 0)
 633                 return err;
 634
 635         /*
 636          * Just after owning the unit (GLOBAL_OWNER), the unit can return
 637          * invalid stream formats. Selecting clock parameters have an effect
 638          * for the unit to refine it.
 639          */
 640         err = select_clock(dice, rate);
 641         if (err < 0)
 642                 return err;
 643
 644         err = get_register_params(dice, &tx_params, &rx_params);
 645         if (err < 0)
 646                 return err;
 647
 648         for (i = 0; i < tx_params.count; ++i) {
 649                 err = snd_dice_transaction_read_tx(dice,
 650                                 tx_params.size * i + TX_NUMBER_AUDIO,
 651                                 reg, sizeof(reg));
 652                 if (err < 0)
 653                         return err;
 654                 dice->tx_pcm_chs[i][mode] = be32_to_cpu(reg[0]);
 655                 dice->tx_midi_ports[i] = max_t(unsigned int,
 656                                 be32_to_cpu(reg[1]), dice->tx_midi_ports[i]);
 657         }
 658         for (i = 0; i < rx_params.count; ++i) {
 659                 err = snd_dice_transaction_read_rx(dice,
 660                                 rx_params.size * i + RX_NUMBER_AUDIO,
 661                                 reg, sizeof(reg));
 662                 if (err < 0)
 663                         return err;
 664                 dice->rx_pcm_chs[i][mode] = be32_to_cpu(reg[0]);
 665                 dice->rx_midi_ports[i] = max_t(unsigned int,
 666                                 be32_to_cpu(reg[1]), dice->rx_midi_ports[i]);
 667         }
 668
 669         return 0;
 670 }
 671
 672 static void dice_lock_changed(struct snd_dice *dice)
 673 {
 674         dice->dev_lock_changed = true;
 675         wake_up(&dice->hwdep_wait);
 676 }
 677
 678 int snd_dice_stream_lock_try(struct snd_dice *dice)
 679 {
 680         int err;
 681
 682         spin_lock_irq(&dice->lock);
 683
 684         if (dice->dev_lock_count < 0) {
 685                 err = -EBUSY;
 686                 goto out;
 687         }
 688
 689         if (dice->dev_lock_count++ == 0)
 690                 dice_lock_changed(dice);
 691         err = 0;
 692 out:
 693         spin_unlock_irq(&dice->lock);
 694         return err;
 695 }
 696
 697 void snd_dice_stream_lock_release(struct snd_dice *dice)
 698 {
 699         spin_lock_irq(&dice->lock);
 700
 701         if (WARN_ON(dice->dev_lock_count <= 0))
 702                 goto out;
 703
 704         if (--dice->dev_lock_count == 0)
 705                 dice_lock_changed(dice);
 706 out:
 707         spin_unlock_irq(&dice->lock);
 708 }