sound/firewire/oxfw/oxfw-stream.c

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