sound/usb/caiaq/audio.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *   Copyright (c) 2006-2008 Daniel Mack, Karsten Wiese
   4 */
   5
   6 #include <linux/device.h>
   7 #include <linux/spinlock.h>
   8 #include <linux/slab.h>
   9 #include <linux/init.h>
  10 #include <linux/usb.h>
  11 #include <sound/core.h>
  12 #include <sound/pcm.h>
  13
  14 #include "device.h"
  15 #include "audio.h"
  16
  17 #define N_URBS                  32
  18 #define CLOCK_DRIFT_TOLERANCE   5
  19 #define FRAMES_PER_URB          8
  20 #define BYTES_PER_FRAME         512
  21 #define CHANNELS_PER_STREAM     2
  22 #define BYTES_PER_SAMPLE        3
  23 #define BYTES_PER_SAMPLE_USB    4
  24 #define MAX_BUFFER_SIZE         (128*1024)
  25 #define MAX_ENDPOINT_SIZE       512
  26
  27 #define ENDPOINT_CAPTURE        2
  28 #define ENDPOINT_PLAYBACK       6
  29
  30 #define MAKE_CHECKBYTE(cdev,stream,i) \
  31         (stream << 1) | (~(i / (cdev->n_streams * BYTES_PER_SAMPLE_USB)) & 1)
  32
  33 static const struct snd_pcm_hardware snd_usb_caiaq_pcm_hardware = {
  34         .info           = (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
  35                            SNDRV_PCM_INFO_BLOCK_TRANSFER),
  36         .formats        = SNDRV_PCM_FMTBIT_S24_3BE,
  37         .rates          = (SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000 |
  38                            SNDRV_PCM_RATE_96000),
  39         .rate_min       = 44100,
  40         .rate_max       = 0, /* will overwrite later */
  41         .channels_min   = CHANNELS_PER_STREAM,
  42         .channels_max   = CHANNELS_PER_STREAM,
  43         .buffer_bytes_max = MAX_BUFFER_SIZE,
  44         .period_bytes_min = 128,
  45         .period_bytes_max = MAX_BUFFER_SIZE,
  46         .periods_min    = 1,
  47         .periods_max    = 1024,
  48 };
  49
  50 static void
  51 activate_substream(struct snd_usb_caiaqdev *cdev,
  52                    struct snd_pcm_substream *sub)
  53 {
  54         spin_lock(&cdev->spinlock);
  55
  56         if (sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
  57                 cdev->sub_playback[sub->number] = sub;
  58         else
  59                 cdev->sub_capture[sub->number] = sub;
  60
  61         spin_unlock(&cdev->spinlock);
  62 }
  63
  64 static void
  65 deactivate_substream(struct snd_usb_caiaqdev *cdev,
  66                      struct snd_pcm_substream *sub)
  67 {
  68         unsigned long flags;
  69         spin_lock_irqsave(&cdev->spinlock, flags);
  70
  71         if (sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
  72                 cdev->sub_playback[sub->number] = NULL;
  73         else
  74                 cdev->sub_capture[sub->number] = NULL;
  75
  76         spin_unlock_irqrestore(&cdev->spinlock, flags);
  77 }
  78
  79 static int
  80 all_substreams_zero(struct snd_pcm_substream **subs)
  81 {
  82         int i;
  83         for (i = 0; i < MAX_STREAMS; i++)
  84                 if (subs[i] != NULL)
  85                         return 0;
  86         return 1;
  87 }
  88
  89 static int stream_start(struct snd_usb_caiaqdev *cdev)
  90 {
  91         int i, ret;
  92         struct device *dev = caiaqdev_to_dev(cdev);
  93
  94         dev_dbg(dev, "%s(%p)\n", __func__, cdev);
  95
  96         if (cdev->streaming)
  97                 return -EINVAL;
  98
  99         memset(cdev->sub_playback, 0, sizeof(cdev->sub_playback));
 100         memset(cdev->sub_capture, 0, sizeof(cdev->sub_capture));
 101         cdev->input_panic = 0;
 102         cdev->output_panic = 0;
 103         cdev->first_packet = 4;
 104         cdev->streaming = 1;
 105         cdev->warned = 0;
 106
 107         for (i = 0; i < N_URBS; i++) {
 108                 ret = usb_submit_urb(cdev->data_urbs_in[i], GFP_ATOMIC);
 109                 if (ret) {
 110                         dev_err(dev, "unable to trigger read #%d! (ret %d)\n",
 111                                 i, ret);
 112                         cdev->streaming = 0;
 113                         return -EPIPE;
 114                 }
 115         }
 116
 117         return 0;
 118 }
 119
 120 static void stream_stop(struct snd_usb_caiaqdev *cdev)
 121 {
 122         int i;
 123         struct device *dev = caiaqdev_to_dev(cdev);
 124
 125         dev_dbg(dev, "%s(%p)\n", __func__, cdev);
 126         if (!cdev->streaming)
 127                 return;
 128
 129         cdev->streaming = 0;
 130
 131         for (i = 0; i < N_URBS; i++) {
 132                 usb_kill_urb(cdev->data_urbs_in[i]);
 133
 134                 if (test_bit(i, &cdev->outurb_active_mask))
 135                         usb_kill_urb(cdev->data_urbs_out[i]);
 136         }
 137
 138         cdev->outurb_active_mask = 0;
 139 }
 140
 141 static int snd_usb_caiaq_substream_open(struct snd_pcm_substream *substream)
 142 {
 143         struct snd_usb_caiaqdev *cdev = snd_pcm_substream_chip(substream);
 144         struct device *dev = caiaqdev_to_dev(cdev);
 145
 146         dev_dbg(dev, "%s(%p)\n", __func__, substream);
 147         substream->runtime->hw = cdev->pcm_info;
 148         snd_pcm_limit_hw_rates(substream->runtime);
 149
 150         return 0;
 151 }
 152
 153 static int snd_usb_caiaq_substream_close(struct snd_pcm_substream *substream)
 154 {
 155         struct snd_usb_caiaqdev *cdev = snd_pcm_substream_chip(substream);
 156         struct device *dev = caiaqdev_to_dev(cdev);
 157
 158         dev_dbg(dev, "%s(%p)\n", __func__, substream);
 159         if (all_substreams_zero(cdev->sub_playback) &&
 160             all_substreams_zero(cdev->sub_capture)) {
 161                 /* when the last client has stopped streaming,
 162                  * all sample rates are allowed again */
 163                 stream_stop(cdev);
 164                 cdev->pcm_info.rates = cdev->samplerates;
 165         }
 166
 167         return 0;
 168 }
 169
 170 static int snd_usb_caiaq_pcm_hw_free(struct snd_pcm_substream *sub)
 171 {
 172         struct snd_usb_caiaqdev *cdev = snd_pcm_substream_chip(sub);
 173         deactivate_substream(cdev, sub);
 174         return 0;
 175 }
 176
 177 /* this should probably go upstream */
 178 #if SNDRV_PCM_RATE_5512 != 1 << 0 || SNDRV_PCM_RATE_192000 != 1 << 12
 179 #error "Change this table"
 180 #endif
 181
 182 static const unsigned int rates[] = { 5512, 8000, 11025, 16000, 22050, 32000, 44100,
 183                                 48000, 64000, 88200, 96000, 176400, 192000 };
 184
 185 static int snd_usb_caiaq_pcm_prepare(struct snd_pcm_substream *substream)
 186 {
 187         int bytes_per_sample, bpp, ret, i;
 188         int index = substream->number;
 189         struct snd_usb_caiaqdev *cdev = snd_pcm_substream_chip(substream);
 190         struct snd_pcm_runtime *runtime = substream->runtime;
 191         struct device *dev = caiaqdev_to_dev(cdev);
 192
 193         dev_dbg(dev, "%s(%p)\n", __func__, substream);
 194
 195         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 196                 int out_pos;
 197
 198                 switch (cdev->spec.data_alignment) {
 199                 case 0:
 200                 case 2:
 201                         out_pos = BYTES_PER_SAMPLE + 1;
 202                         break;
 203                 case 3:
 204                 default:
 205                         out_pos = 0;
 206                         break;
 207                 }
 208
 209                 cdev->period_out_count[index] = out_pos;
 210                 cdev->audio_out_buf_pos[index] = out_pos;
 211         } else {
 212                 int in_pos;
 213
 214                 switch (cdev->spec.data_alignment) {
 215                 case 0:
 216                         in_pos = BYTES_PER_SAMPLE + 2;
 217                         break;
 218                 case 2:
 219                         in_pos = BYTES_PER_SAMPLE;
 220                         break;
 221                 case 3:
 222                 default:
 223                         in_pos = 0;
 224                         break;
 225                 }
 226
 227                 cdev->period_in_count[index] = in_pos;
 228                 cdev->audio_in_buf_pos[index] = in_pos;
 229         }
 230
 231         if (cdev->streaming)
 232                 return 0;
 233
 234         /* the first client that opens a stream defines the sample rate
 235          * setting for all subsequent calls, until the last client closed. */
 236         for (i=0; i < ARRAY_SIZE(rates); i++)
 237                 if (runtime->rate == rates[i])
 238                         cdev->pcm_info.rates = 1 << i;
 239
 240         snd_pcm_limit_hw_rates(runtime);
 241
 242         bytes_per_sample = BYTES_PER_SAMPLE;
 243         if (cdev->spec.data_alignment >= 2)
 244                 bytes_per_sample++;
 245
 246         bpp = ((runtime->rate / 8000) + CLOCK_DRIFT_TOLERANCE)
 247                 * bytes_per_sample * CHANNELS_PER_STREAM * cdev->n_streams;
 248
 249         if (bpp > MAX_ENDPOINT_SIZE)
 250                 bpp = MAX_ENDPOINT_SIZE;
 251
 252         ret = snd_usb_caiaq_set_audio_params(cdev, runtime->rate,
 253                                              runtime->sample_bits, bpp);
 254         if (ret)
 255                 return ret;
 256
 257         ret = stream_start(cdev);
 258         if (ret)
 259                 return ret;
 260
 261         cdev->output_running = 0;
 262         wait_event_timeout(cdev->prepare_wait_queue, cdev->output_running, HZ);
 263         if (!cdev->output_running) {
 264                 stream_stop(cdev);
 265                 return -EPIPE;
 266         }
 267
 268         return 0;
 269 }
 270
 271 static int snd_usb_caiaq_pcm_trigger(struct snd_pcm_substream *sub, int cmd)
 272 {
 273         struct snd_usb_caiaqdev *cdev = snd_pcm_substream_chip(sub);
 274         struct device *dev = caiaqdev_to_dev(cdev);
 275
 276         dev_dbg(dev, "%s(%p) cmd %d\n", __func__, sub, cmd);
 277
 278         switch (cmd) {
 279         case SNDRV_PCM_TRIGGER_START:
 280         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 281                 activate_substream(cdev, sub);
 282                 break;
 283         case SNDRV_PCM_TRIGGER_STOP:
 284         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 285                 deactivate_substream(cdev, sub);
 286                 break;
 287         default:
 288                 return -EINVAL;
 289         }
 290
 291         return 0;
 292 }
 293
 294 static snd_pcm_uframes_t
 295 snd_usb_caiaq_pcm_pointer(struct snd_pcm_substream *sub)
 296 {
 297         int index = sub->number;
 298         struct snd_usb_caiaqdev *cdev = snd_pcm_substream_chip(sub);
 299         snd_pcm_uframes_t ptr;
 300
 301         spin_lock(&cdev->spinlock);
 302
 303         if (cdev->input_panic || cdev->output_panic) {
 304                 ptr = SNDRV_PCM_POS_XRUN;
 305                 goto unlock;
 306         }
 307
 308         if (sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
 309                 ptr = bytes_to_frames(sub->runtime,
 310                                         cdev->audio_out_buf_pos[index]);
 311         else
 312                 ptr = bytes_to_frames(sub->runtime,
 313                                         cdev->audio_in_buf_pos[index]);
 314
 315 unlock:
 316         spin_unlock(&cdev->spinlock);
 317         return ptr;
 318 }
 319
 320 /* operators for both playback and capture */
 321 static const struct snd_pcm_ops snd_usb_caiaq_ops = {
 322         .open =         snd_usb_caiaq_substream_open,
 323         .close =        snd_usb_caiaq_substream_close,
 324         .hw_free =      snd_usb_caiaq_pcm_hw_free,
 325         .prepare =      snd_usb_caiaq_pcm_prepare,
 326         .trigger =      snd_usb_caiaq_pcm_trigger,
 327         .pointer =      snd_usb_caiaq_pcm_pointer,
 328 };
 329
 330 static void check_for_elapsed_periods(struct snd_usb_caiaqdev *cdev,
 331                                       struct snd_pcm_substream **subs)
 332 {
 333         int stream, pb, *cnt;
 334         struct snd_pcm_substream *sub;
 335
 336         for (stream = 0; stream < cdev->n_streams; stream++) {
 337                 sub = subs[stream];
 338                 if (!sub)
 339                         continue;
 340
 341                 pb = snd_pcm_lib_period_bytes(sub);
 342                 cnt = (sub->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
 343                                         &cdev->period_out_count[stream] :
 344                                         &cdev->period_in_count[stream];
 345
 346                 if (*cnt >= pb) {
 347                         snd_pcm_period_elapsed(sub);
 348                         *cnt %= pb;
 349                 }
 350         }
 351 }
 352
 353 static void read_in_urb_mode0(struct snd_usb_caiaqdev *cdev,
 354                               const struct urb *urb,
 355                               const struct usb_iso_packet_descriptor *iso)
 356 {
 357         unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
 358         struct snd_pcm_substream *sub;
 359         int stream, i;
 360
 361         if (all_substreams_zero(cdev->sub_capture))
 362                 return;
 363
 364         for (i = 0; i < iso->actual_length;) {
 365                 for (stream = 0; stream < cdev->n_streams; stream++, i++) {
 366                         sub = cdev->sub_capture[stream];
 367                         if (sub) {
 368                                 struct snd_pcm_runtime *rt = sub->runtime;
 369                                 char *audio_buf = rt->dma_area;
 370                                 int sz = frames_to_bytes(rt, rt->buffer_size);
 371                                 audio_buf[cdev->audio_in_buf_pos[stream]++]
 372                                         = usb_buf[i];
 373                                 cdev->period_in_count[stream]++;
 374                                 if (cdev->audio_in_buf_pos[stream] == sz)
 375                                         cdev->audio_in_buf_pos[stream] = 0;
 376                         }
 377                 }
 378         }
 379 }
 380
 381 static void read_in_urb_mode2(struct snd_usb_caiaqdev *cdev,
 382                               const struct urb *urb,
 383                               const struct usb_iso_packet_descriptor *iso)
 384 {
 385         unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
 386         unsigned char check_byte;
 387         struct snd_pcm_substream *sub;
 388         int stream, i;
 389
 390         for (i = 0; i < iso->actual_length;) {
 391                 if (i % (cdev->n_streams * BYTES_PER_SAMPLE_USB) == 0) {
 392                         for (stream = 0;
 393                              stream < cdev->n_streams;
 394                              stream++, i++) {
 395                                 if (cdev->first_packet)
 396                                         continue;
 397
 398                                 check_byte = MAKE_CHECKBYTE(cdev, stream, i);
 399
 400                                 if ((usb_buf[i] & 0x3f) != check_byte)
 401                                         cdev->input_panic = 1;
 402
 403                                 if (usb_buf[i] & 0x80)
 404                                         cdev->output_panic = 1;
 405                         }
 406                 }
 407                 cdev->first_packet = 0;
 408
 409                 for (stream = 0; stream < cdev->n_streams; stream++, i++) {
 410                         sub = cdev->sub_capture[stream];
 411                         if (cdev->input_panic)
 412                                 usb_buf[i] = 0;
 413
 414                         if (sub) {
 415                                 struct snd_pcm_runtime *rt = sub->runtime;
 416                                 char *audio_buf = rt->dma_area;
 417                                 int sz = frames_to_bytes(rt, rt->buffer_size);
 418                                 audio_buf[cdev->audio_in_buf_pos[stream]++] =
 419                                         usb_buf[i];
 420                                 cdev->period_in_count[stream]++;
 421                                 if (cdev->audio_in_buf_pos[stream] == sz)
 422                                         cdev->audio_in_buf_pos[stream] = 0;
 423                         }
 424                 }
 425         }
 426 }
 427
 428 static void read_in_urb_mode3(struct snd_usb_caiaqdev *cdev,
 429                               const struct urb *urb,
 430                               const struct usb_iso_packet_descriptor *iso)
 431 {
 432         unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
 433         struct device *dev = caiaqdev_to_dev(cdev);
 434         int stream, i;
 435
 436         /* paranoia check */
 437         if (iso->actual_length % (BYTES_PER_SAMPLE_USB * CHANNELS_PER_STREAM))
 438                 return;
 439
 440         for (i = 0; i < iso->actual_length;) {
 441                 for (stream = 0; stream < cdev->n_streams; stream++) {
 442                         struct snd_pcm_substream *sub = cdev->sub_capture[stream];
 443                         char *audio_buf = NULL;
 444                         int c, n, sz = 0;
 445
 446                         if (sub && !cdev->input_panic) {
 447                                 struct snd_pcm_runtime *rt = sub->runtime;
 448                                 audio_buf = rt->dma_area;
 449                                 sz = frames_to_bytes(rt, rt->buffer_size);
 450                         }
 451
 452                         for (c = 0; c < CHANNELS_PER_STREAM; c++) {
 453                                 /* 3 audio data bytes, followed by 1 check byte */
 454                                 if (audio_buf) {
 455                                         for (n = 0; n < BYTES_PER_SAMPLE; n++) {
 456                                                 audio_buf[cdev->audio_in_buf_pos[stream]++] = usb_buf[i+n];
 457
 458                                                 if (cdev->audio_in_buf_pos[stream] == sz)
 459                                                         cdev->audio_in_buf_pos[stream] = 0;
 460                                         }
 461
 462                                         cdev->period_in_count[stream] += BYTES_PER_SAMPLE;
 463                                 }
 464
 465                                 i += BYTES_PER_SAMPLE;
 466
 467                                 if (usb_buf[i] != ((stream << 1) | c) &&
 468                                     !cdev->first_packet) {
 469                                         if (!cdev->input_panic)
 470                                                 dev_warn(dev, " EXPECTED: %02x got %02x, c %d, stream %d, i %d\n",
 471                                                          ((stream << 1) | c), usb_buf[i], c, stream, i);
 472                                         cdev->input_panic = 1;
 473                                 }
 474
 475                                 i++;
 476                         }
 477                 }
 478         }
 479
 480         if (cdev->first_packet > 0)
 481                 cdev->first_packet--;
 482 }
 483
 484 static void read_in_urb(struct snd_usb_caiaqdev *cdev,
 485                         const struct urb *urb,
 486                         const struct usb_iso_packet_descriptor *iso)
 487 {
 488         struct device *dev = caiaqdev_to_dev(cdev);
 489
 490         if (!cdev->streaming)
 491                 return;
 492
 493         if (iso->actual_length < cdev->bpp)
 494                 return;
 495
 496         switch (cdev->spec.data_alignment) {
 497         case 0:
 498                 read_in_urb_mode0(cdev, urb, iso);
 499                 break;
 500         case 2:
 501                 read_in_urb_mode2(cdev, urb, iso);
 502                 break;
 503         case 3:
 504                 read_in_urb_mode3(cdev, urb, iso);
 505                 break;
 506         }
 507
 508         if ((cdev->input_panic || cdev->output_panic) && !cdev->warned) {
 509                 dev_warn(dev, "streaming error detected %s %s\n",
 510                                 cdev->input_panic ? "(input)" : "",
 511                                 cdev->output_panic ? "(output)" : "");
 512                 cdev->warned = 1;
 513         }
 514 }
 515
 516 static void fill_out_urb_mode_0(struct snd_usb_caiaqdev *cdev,
 517                                 struct urb *urb,
 518                                 const struct usb_iso_packet_descriptor *iso)
 519 {
 520         unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
 521         struct snd_pcm_substream *sub;
 522         int stream, i;
 523
 524         for (i = 0; i < iso->length;) {
 525                 for (stream = 0; stream < cdev->n_streams; stream++, i++) {
 526                         sub = cdev->sub_playback[stream];
 527                         if (sub) {
 528                                 struct snd_pcm_runtime *rt = sub->runtime;
 529                                 char *audio_buf = rt->dma_area;
 530                                 int sz = frames_to_bytes(rt, rt->buffer_size);
 531                                 usb_buf[i] =
 532                                         audio_buf[cdev->audio_out_buf_pos[stream]];
 533                                 cdev->period_out_count[stream]++;
 534                                 cdev->audio_out_buf_pos[stream]++;
 535                                 if (cdev->audio_out_buf_pos[stream] == sz)
 536                                         cdev->audio_out_buf_pos[stream] = 0;
 537                         } else
 538                                 usb_buf[i] = 0;
 539                 }
 540
 541                 /* fill in the check bytes */
 542                 if (cdev->spec.data_alignment == 2 &&
 543                     i % (cdev->n_streams * BYTES_PER_SAMPLE_USB) ==
 544                         (cdev->n_streams * CHANNELS_PER_STREAM))
 545                         for (stream = 0; stream < cdev->n_streams; stream++, i++)
 546                                 usb_buf[i] = MAKE_CHECKBYTE(cdev, stream, i);
 547         }
 548 }
 549
 550 static void fill_out_urb_mode_3(struct snd_usb_caiaqdev *cdev,
 551                                 struct urb *urb,
 552                                 const struct usb_iso_packet_descriptor *iso)
 553 {
 554         unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
 555         int stream, i;
 556
 557         for (i = 0; i < iso->length;) {
 558                 for (stream = 0; stream < cdev->n_streams; stream++) {
 559                         struct snd_pcm_substream *sub = cdev->sub_playback[stream];
 560                         char *audio_buf = NULL;
 561                         int c, n, sz = 0;
 562
 563                         if (sub) {
 564                                 struct snd_pcm_runtime *rt = sub->runtime;
 565                                 audio_buf = rt->dma_area;
 566                                 sz = frames_to_bytes(rt, rt->buffer_size);
 567                         }
 568
 569                         for (c = 0; c < CHANNELS_PER_STREAM; c++) {
 570                                 for (n = 0; n < BYTES_PER_SAMPLE; n++) {
 571                                         if (audio_buf) {
 572                                                 usb_buf[i+n] = audio_buf[cdev->audio_out_buf_pos[stream]++];
 573
 574                                                 if (cdev->audio_out_buf_pos[stream] == sz)
 575                                                         cdev->audio_out_buf_pos[stream] = 0;
 576                                         } else {
 577                                                 usb_buf[i+n] = 0;
 578                                         }
 579                                 }
 580
 581                                 if (audio_buf)
 582                                         cdev->period_out_count[stream] += BYTES_PER_SAMPLE;
 583
 584                                 i += BYTES_PER_SAMPLE;
 585
 586                                 /* fill in the check byte pattern */
 587                                 usb_buf[i++] = (stream << 1) | c;
 588                         }
 589                 }
 590         }
 591 }
 592
 593 static inline void fill_out_urb(struct snd_usb_caiaqdev *cdev,
 594                                 struct urb *urb,
 595                                 const struct usb_iso_packet_descriptor *iso)
 596 {
 597         switch (cdev->spec.data_alignment) {
 598         case 0:
 599         case 2:
 600                 fill_out_urb_mode_0(cdev, urb, iso);
 601                 break;
 602         case 3:
 603                 fill_out_urb_mode_3(cdev, urb, iso);
 604                 break;
 605         }
 606 }
 607
 608 static void read_completed(struct urb *urb)
 609 {
 610         struct snd_usb_caiaq_cb_info *info = urb->context;
 611         struct snd_usb_caiaqdev *cdev;
 612         struct device *dev;
 613         struct urb *out = NULL;
 614         int i, frame, len, send_it = 0, outframe = 0;
 615         unsigned long flags;
 616         size_t offset = 0;
 617
 618         if (urb->status || !info)
 619                 return;
 620
 621         cdev = info->cdev;
 622         dev = caiaqdev_to_dev(cdev);
 623
 624         if (!cdev->streaming)
 625                 return;
 626
 627         /* find an unused output urb that is unused */
 628         for (i = 0; i < N_URBS; i++)
 629                 if (test_and_set_bit(i, &cdev->outurb_active_mask) == 0) {
 630                         out = cdev->data_urbs_out[i];
 631                         break;
 632                 }
 633
 634         if (!out) {
 635                 dev_err(dev, "Unable to find an output urb to use\n");
 636                 goto requeue;
 637         }
 638
 639         /* read the recently received packet and send back one which has
 640          * the same layout */
 641         for (frame = 0; frame < FRAMES_PER_URB; frame++) {
 642                 if (urb->iso_frame_desc[frame].status)
 643                         continue;
 644
 645                 len = urb->iso_frame_desc[outframe].actual_length;
 646                 out->iso_frame_desc[outframe].length = len;
 647                 out->iso_frame_desc[outframe].actual_length = 0;
 648                 out->iso_frame_desc[outframe].offset = offset;
 649                 offset += len;
 650
 651                 if (len > 0) {
 652                         spin_lock_irqsave(&cdev->spinlock, flags);
 653                         fill_out_urb(cdev, out, &out->iso_frame_desc[outframe]);
 654                         read_in_urb(cdev, urb, &urb->iso_frame_desc[frame]);
 655                         spin_unlock_irqrestore(&cdev->spinlock, flags);
 656                         check_for_elapsed_periods(cdev, cdev->sub_playback);
 657                         check_for_elapsed_periods(cdev, cdev->sub_capture);
 658                         send_it = 1;
 659                 }
 660
 661                 outframe++;
 662         }
 663
 664         if (send_it) {
 665                 out->number_of_packets = outframe;
 666                 usb_submit_urb(out, GFP_ATOMIC);
 667         } else {
 668                 struct snd_usb_caiaq_cb_info *oinfo = out->context;
 669                 clear_bit(oinfo->index, &cdev->outurb_active_mask);
 670         }
 671
 672 requeue:
 673         /* re-submit inbound urb */
 674         for (frame = 0; frame < FRAMES_PER_URB; frame++) {
 675                 urb->iso_frame_desc[frame].offset = BYTES_PER_FRAME * frame;
 676                 urb->iso_frame_desc[frame].length = BYTES_PER_FRAME;
 677                 urb->iso_frame_desc[frame].actual_length = 0;
 678         }
 679
 680         urb->number_of_packets = FRAMES_PER_URB;
 681         usb_submit_urb(urb, GFP_ATOMIC);
 682 }
 683
 684 static void write_completed(struct urb *urb)
 685 {
 686         struct snd_usb_caiaq_cb_info *info = urb->context;
 687         struct snd_usb_caiaqdev *cdev = info->cdev;
 688
 689         if (!cdev->output_running) {
 690                 cdev->output_running = 1;
 691                 wake_up(&cdev->prepare_wait_queue);
 692         }
 693
 694         clear_bit(info->index, &cdev->outurb_active_mask);
 695 }
 696
 697 static struct urb **alloc_urbs(struct snd_usb_caiaqdev *cdev, int dir, int *ret)
 698 {
 699         int i, frame;
 700         struct urb **urbs;
 701         struct usb_device *usb_dev = cdev->chip.dev;
 702         unsigned int pipe;
 703
 704         pipe = (dir == SNDRV_PCM_STREAM_PLAYBACK) ?
 705                 usb_sndisocpipe(usb_dev, ENDPOINT_PLAYBACK) :
 706                 usb_rcvisocpipe(usb_dev, ENDPOINT_CAPTURE);
 707
 708         urbs = kmalloc_array(N_URBS, sizeof(*urbs), GFP_KERNEL);
 709         if (!urbs) {
 710                 *ret = -ENOMEM;
 711                 return NULL;
 712         }
 713
 714         for (i = 0; i < N_URBS; i++) {
 715                 urbs[i] = usb_alloc_urb(FRAMES_PER_URB, GFP_KERNEL);
 716                 if (!urbs[i]) {
 717                         *ret = -ENOMEM;
 718                         return urbs;
 719                 }
 720
 721                 urbs[i]->transfer_buffer =
 722                         kmalloc_array(BYTES_PER_FRAME, FRAMES_PER_URB,
 723                                       GFP_KERNEL);
 724                 if (!urbs[i]->transfer_buffer) {
 725                         *ret = -ENOMEM;
 726                         return urbs;
 727                 }
 728
 729                 for (frame = 0; frame < FRAMES_PER_URB; frame++) {
 730                         struct usb_iso_packet_descriptor *iso =
 731                                 &urbs[i]->iso_frame_desc[frame];
 732
 733                         iso->offset = BYTES_PER_FRAME * frame;
 734                         iso->length = BYTES_PER_FRAME;
 735                 }
 736
 737                 urbs[i]->dev = usb_dev;
 738                 urbs[i]->pipe = pipe;
 739                 urbs[i]->transfer_buffer_length = FRAMES_PER_URB
 740                                                 * BYTES_PER_FRAME;
 741                 urbs[i]->context = &cdev->data_cb_info[i];
 742                 urbs[i]->interval = 1;
 743                 urbs[i]->number_of_packets = FRAMES_PER_URB;
 744                 urbs[i]->complete = (dir == SNDRV_PCM_STREAM_CAPTURE) ?
 745                                         read_completed : write_completed;
 746         }
 747
 748         *ret = 0;
 749         return urbs;
 750 }
 751
 752 static void free_urbs(struct urb **urbs)
 753 {
 754         int i;
 755
 756         if (!urbs)
 757                 return;
 758
 759         for (i = 0; i < N_URBS; i++) {
 760                 if (!urbs[i])
 761                         continue;
 762
 763                 usb_kill_urb(urbs[i]);
 764                 kfree(urbs[i]->transfer_buffer);
 765                 usb_free_urb(urbs[i]);
 766         }
 767
 768         kfree(urbs);
 769 }
 770
 771 int snd_usb_caiaq_audio_init(struct snd_usb_caiaqdev *cdev)
 772 {
 773         int i, ret;
 774         struct device *dev = caiaqdev_to_dev(cdev);
 775
 776         cdev->n_audio_in  = max(cdev->spec.num_analog_audio_in,
 777                                cdev->spec.num_digital_audio_in) /
 778                                 CHANNELS_PER_STREAM;
 779         cdev->n_audio_out = max(cdev->spec.num_analog_audio_out,
 780                                cdev->spec.num_digital_audio_out) /
 781                                 CHANNELS_PER_STREAM;
 782         cdev->n_streams = max(cdev->n_audio_in, cdev->n_audio_out);
 783
 784         dev_dbg(dev, "cdev->n_audio_in = %d\n", cdev->n_audio_in);
 785         dev_dbg(dev, "cdev->n_audio_out = %d\n", cdev->n_audio_out);
 786         dev_dbg(dev, "cdev->n_streams = %d\n", cdev->n_streams);
 787
 788         if (cdev->n_streams > MAX_STREAMS) {
 789                 dev_err(dev, "unable to initialize device, too many streams.\n");
 790                 return -EINVAL;
 791         }
 792
 793         if (cdev->n_streams < 1) {
 794                 dev_err(dev, "bogus number of streams: %d\n", cdev->n_streams);
 795                 return -EINVAL;
 796         }
 797
 798         ret = snd_pcm_new(cdev->chip.card, cdev->product_name, 0,
 799                         cdev->n_audio_out, cdev->n_audio_in, &cdev->pcm);
 800
 801         if (ret < 0) {
 802                 dev_err(dev, "snd_pcm_new() returned %d\n", ret);
 803                 return ret;
 804         }
 805
 806         cdev->pcm->private_data = cdev;
 807         strscpy(cdev->pcm->name, cdev->product_name, sizeof(cdev->pcm->name));
 808
 809         memset(cdev->sub_playback, 0, sizeof(cdev->sub_playback));
 810         memset(cdev->sub_capture, 0, sizeof(cdev->sub_capture));
 811
 812         memcpy(&cdev->pcm_info, &snd_usb_caiaq_pcm_hardware,
 813                         sizeof(snd_usb_caiaq_pcm_hardware));
 814
 815         /* setup samplerates */
 816         cdev->samplerates = cdev->pcm_info.rates;
 817         switch (cdev->chip.usb_id) {
 818         case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_AK1):
 819         case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_RIGKONTROL3):
 820         case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_SESSIONIO):
 821         case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_GUITARRIGMOBILE):
 822                 cdev->samplerates |= SNDRV_PCM_RATE_192000;
 823                 fallthrough;
 824         case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_AUDIO2DJ):
 825         case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_AUDIO4DJ):
 826         case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_AUDIO8DJ):
 827         case USB_ID(USB_VID_NATIVEINSTRUMENTS, USB_PID_TRAKTORAUDIO2):
 828                 cdev->samplerates |= SNDRV_PCM_RATE_88200;
 829                 break;
 830         }
 831
 832         snd_pcm_set_ops(cdev->pcm, SNDRV_PCM_STREAM_PLAYBACK,
 833                                 &snd_usb_caiaq_ops);
 834         snd_pcm_set_ops(cdev->pcm, SNDRV_PCM_STREAM_CAPTURE,
 835                                 &snd_usb_caiaq_ops);
 836         snd_pcm_set_managed_buffer_all(cdev->pcm, SNDRV_DMA_TYPE_VMALLOC,
 837                                        NULL, 0, 0);
 838
 839         cdev->data_cb_info =
 840                 kmalloc_array(N_URBS, sizeof(struct snd_usb_caiaq_cb_info),
 841                                         GFP_KERNEL);
 842
 843         if (!cdev->data_cb_info)
 844                 return -ENOMEM;
 845
 846         cdev->outurb_active_mask = 0;
 847         BUILD_BUG_ON(N_URBS > (sizeof(cdev->outurb_active_mask) * 8));
 848
 849         for (i = 0; i < N_URBS; i++) {
 850                 cdev->data_cb_info[i].cdev = cdev;
 851                 cdev->data_cb_info[i].index = i;
 852         }
 853
 854         cdev->data_urbs_in = alloc_urbs(cdev, SNDRV_PCM_STREAM_CAPTURE, &ret);
 855         if (ret < 0) {
 856                 kfree(cdev->data_cb_info);
 857                 free_urbs(cdev->data_urbs_in);
 858                 return ret;
 859         }
 860
 861         cdev->data_urbs_out = alloc_urbs(cdev, SNDRV_PCM_STREAM_PLAYBACK, &ret);
 862         if (ret < 0) {
 863                 kfree(cdev->data_cb_info);
 864                 free_urbs(cdev->data_urbs_in);
 865                 free_urbs(cdev->data_urbs_out);
 866                 return ret;
 867         }
 868
 869         return 0;
 870 }
 871
 872 void snd_usb_caiaq_audio_free(struct snd_usb_caiaqdev *cdev)
 873 {
 874         struct device *dev = caiaqdev_to_dev(cdev);
 875
 876         dev_dbg(dev, "%s(%p)\n", __func__, cdev);
 877         stream_stop(cdev);
 878         free_urbs(cdev->data_urbs_in);
 879         free_urbs(cdev->data_urbs_out);
 880         kfree(cdev->data_cb_info);
 881 }
 882