sound/usb/endpoint.c

   1 /*
   2  *   This program is free software; you can redistribute it and/or modify
   3  *   it under the terms of the GNU General Public License as published by
   4  *   the Free Software Foundation; either version 2 of the License, or
   5  *   (at your option) any later version.
   6  *
   7  *   This program is distributed in the hope that it will be useful,
   8  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  *   GNU General Public License for more details.
  11  *
  12  *   You should have received a copy of the GNU General Public License
  13  *   along with this program; if not, write to the Free Software
  14  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  15  *
  16  */
  17
  18 #include <linux/gfp.h>
  19 #include <linux/init.h>
  20 #include <linux/ratelimit.h>
  21 #include <linux/usb.h>
  22 #include <linux/usb/audio.h>
  23
  24 #include <sound/core.h>
  25 #include <sound/pcm.h>
  26
  27 #include "usbaudio.h"
  28 #include "helper.h"
  29 #include "card.h"
  30 #include "endpoint.h"
  31 #include "pcm.h"
  32
  33 /*
  34  * convert a sampling rate into our full speed format (fs/1000 in Q16.16)
  35  * this will overflow at approx 524 kHz
  36  */
  37 static inline unsigned get_usb_full_speed_rate(unsigned int rate)
  38 {
  39         return ((rate << 13) + 62) / 125;
  40 }
  41
  42 /*
  43  * convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
  44  * this will overflow at approx 4 MHz
  45  */
  46 static inline unsigned get_usb_high_speed_rate(unsigned int rate)
  47 {
  48         return ((rate << 10) + 62) / 125;
  49 }
  50
  51 /*
  52  * unlink active urbs.
  53  */
  54 static int deactivate_urbs(struct snd_usb_substream *subs, int force, int can_sleep)
  55 {
  56         struct snd_usb_audio *chip = subs->stream->chip;
  57         unsigned int i;
  58         int async;
  59
  60         subs->running = 0;
  61
  62         if (!force && subs->stream->chip->shutdown) /* to be sure... */
  63                 return -EBADFD;
  64
  65         async = !can_sleep && chip->async_unlink;
  66
  67         if (!async && in_interrupt())
  68                 return 0;
  69
  70         for (i = 0; i < subs->nurbs; i++) {
  71                 if (test_bit(i, &subs->active_mask)) {
  72                         if (!test_and_set_bit(i, &subs->unlink_mask)) {
  73                                 struct urb *u = subs->dataurb[i].urb;
  74                                 if (async)
  75                                         usb_unlink_urb(u);
  76                                 else
  77                                         usb_kill_urb(u);
  78                         }
  79                 }
  80         }
  81         if (subs->syncpipe) {
  82                 for (i = 0; i < SYNC_URBS; i++) {
  83                         if (test_bit(i+16, &subs->active_mask)) {
  84                                 if (!test_and_set_bit(i+16, &subs->unlink_mask)) {
  85                                         struct urb *u = subs->syncurb[i].urb;
  86                                         if (async)
  87                                                 usb_unlink_urb(u);
  88                                         else
  89                                                 usb_kill_urb(u);
  90                                 }
  91                         }
  92                 }
  93         }
  94         return 0;
  95 }
  96
  97
  98 /*
  99  * release a urb data
 100  */
 101 static void release_urb_ctx(struct snd_urb_ctx *u)
 102 {
 103         if (u->urb) {
 104                 if (u->buffer_size)
 105                         usb_free_coherent(u->subs->dev, u->buffer_size,
 106                                         u->urb->transfer_buffer,
 107                                         u->urb->transfer_dma);
 108                 usb_free_urb(u->urb);
 109                 u->urb = NULL;
 110         }
 111 }
 112
 113 /*
 114  *  wait until all urbs are processed.
 115  */
 116 static int wait_clear_urbs(struct snd_usb_substream *subs)
 117 {
 118         unsigned long end_time = jiffies + msecs_to_jiffies(1000);
 119         unsigned int i;
 120         int alive;
 121
 122         do {
 123                 alive = 0;
 124                 for (i = 0; i < subs->nurbs; i++) {
 125                         if (test_bit(i, &subs->active_mask))
 126                                 alive++;
 127                 }
 128                 if (subs->syncpipe) {
 129                         for (i = 0; i < SYNC_URBS; i++) {
 130                                 if (test_bit(i + 16, &subs->active_mask))
 131                                         alive++;
 132                         }
 133                 }
 134                 if (! alive)
 135                         break;
 136                 schedule_timeout_uninterruptible(1);
 137         } while (time_before(jiffies, end_time));
 138         if (alive)
 139                 snd_printk(KERN_ERR "timeout: still %d active urbs..\n", alive);
 140         return 0;
 141 }
 142
 143 /*
 144  * release a substream
 145  */
 146 void snd_usb_release_substream_urbs(struct snd_usb_substream *subs, int force)
 147 {
 148         int i;
 149
 150         /* stop urbs (to be sure) */
 151         deactivate_urbs(subs, force, 1);
 152         wait_clear_urbs(subs);
 153
 154         for (i = 0; i < MAX_URBS; i++)
 155                 release_urb_ctx(&subs->dataurb[i]);
 156         for (i = 0; i < SYNC_URBS; i++)
 157                 release_urb_ctx(&subs->syncurb[i]);
 158         usb_free_coherent(subs->dev, SYNC_URBS * 4,
 159                         subs->syncbuf, subs->sync_dma);
 160         subs->syncbuf = NULL;
 161         subs->nurbs = 0;
 162 }
 163
 164 /*
 165  * complete callback from data urb
 166  */
 167 static void snd_complete_urb(struct urb *urb)
 168 {
 169         struct snd_urb_ctx *ctx = urb->context;
 170         struct snd_usb_substream *subs = ctx->subs;
 171         struct snd_pcm_substream *substream = ctx->subs->pcm_substream;
 172         int err = 0;
 173
 174         if ((subs->running && subs->ops.retire(subs, substream->runtime, urb)) ||
 175             !subs->running || /* can be stopped during retire callback */
 176             (err = subs->ops.prepare(subs, substream->runtime, urb)) < 0 ||
 177             (err = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
 178                 clear_bit(ctx->index, &subs->active_mask);
 179                 if (err < 0) {
 180                         snd_printd(KERN_ERR "cannot submit urb (err = %d)\n", err);
 181                         snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 182                 }
 183         }
 184 }
 185
 186
 187 /*
 188  * complete callback from sync urb
 189  */
 190 static void snd_complete_sync_urb(struct urb *urb)
 191 {
 192         struct snd_urb_ctx *ctx = urb->context;
 193         struct snd_usb_substream *subs = ctx->subs;
 194         struct snd_pcm_substream *substream = ctx->subs->pcm_substream;
 195         int err = 0;
 196
 197         if ((subs->running && subs->ops.retire_sync(subs, substream->runtime, urb)) ||
 198             !subs->running || /* can be stopped during retire callback */
 199             (err = subs->ops.prepare_sync(subs, substream->runtime, urb)) < 0 ||
 200             (err = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
 201                 clear_bit(ctx->index + 16, &subs->active_mask);
 202                 if (err < 0) {
 203                         snd_printd(KERN_ERR "cannot submit sync urb (err = %d)\n", err);
 204                         snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 205                 }
 206         }
 207 }
 208
 209
 210 /*
 211  * initialize a substream for plaback/capture
 212  */
 213 int snd_usb_init_substream_urbs(struct snd_usb_substream *subs,
 214                                 unsigned int period_bytes,
 215                                 unsigned int rate,
 216                                 unsigned int frame_bits)
 217 {
 218         unsigned int maxsize, i;
 219         int is_playback = subs->direction == SNDRV_PCM_STREAM_PLAYBACK;
 220         unsigned int urb_packs, total_packs, packs_per_ms;
 221         struct snd_usb_audio *chip = subs->stream->chip;
 222
 223         /* calculate the frequency in 16.16 format */
 224         if (snd_usb_get_speed(subs->dev) == USB_SPEED_FULL)
 225                 subs->freqn = get_usb_full_speed_rate(rate);
 226         else
 227                 subs->freqn = get_usb_high_speed_rate(rate);
 228         subs->freqm = subs->freqn;
 229         subs->freqshift = INT_MIN;
 230         /* calculate max. frequency */
 231         if (subs->maxpacksize) {
 232                 /* whatever fits into a max. size packet */
 233                 maxsize = subs->maxpacksize;
 234                 subs->freqmax = (maxsize / (frame_bits >> 3))
 235                                 << (16 - subs->datainterval);
 236         } else {
 237                 /* no max. packet size: just take 25% higher than nominal */
 238                 subs->freqmax = subs->freqn + (subs->freqn >> 2);
 239                 maxsize = ((subs->freqmax + 0xffff) * (frame_bits >> 3))
 240                                 >> (16 - subs->datainterval);
 241         }
 242         subs->phase = 0;
 243
 244         if (subs->fill_max)
 245                 subs->curpacksize = subs->maxpacksize;
 246         else
 247                 subs->curpacksize = maxsize;
 248
 249         if (snd_usb_get_speed(subs->dev) != USB_SPEED_FULL)
 250                 packs_per_ms = 8 >> subs->datainterval;
 251         else
 252                 packs_per_ms = 1;
 253
 254         if (is_playback) {
 255                 urb_packs = max(chip->nrpacks, 1);
 256                 urb_packs = min(urb_packs, (unsigned int)MAX_PACKS);
 257         } else
 258                 urb_packs = 1;
 259         urb_packs *= packs_per_ms;
 260         if (subs->syncpipe)
 261                 urb_packs = min(urb_packs, 1U << subs->syncinterval);
 262
 263         /* decide how many packets to be used */
 264         if (is_playback) {
 265                 unsigned int minsize, maxpacks;
 266                 /* determine how small a packet can be */
 267                 minsize = (subs->freqn >> (16 - subs->datainterval))
 268                           * (frame_bits >> 3);
 269                 /* with sync from device, assume it can be 12% lower */
 270                 if (subs->syncpipe)
 271                         minsize -= minsize >> 3;
 272                 minsize = max(minsize, 1u);
 273                 total_packs = (period_bytes + minsize - 1) / minsize;
 274                 /* we need at least two URBs for queueing */
 275                 if (total_packs < 2) {
 276                         total_packs = 2;
 277                 } else {
 278                         /* and we don't want too long a queue either */
 279                         maxpacks = max(MAX_QUEUE * packs_per_ms, urb_packs * 2);
 280                         total_packs = min(total_packs, maxpacks);
 281                 }
 282         } else {
 283                 while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
 284                         urb_packs >>= 1;
 285                 total_packs = MAX_URBS * urb_packs;
 286         }
 287         subs->nurbs = (total_packs + urb_packs - 1) / urb_packs;
 288         if (subs->nurbs > MAX_URBS) {
 289                 /* too much... */
 290                 subs->nurbs = MAX_URBS;
 291                 total_packs = MAX_URBS * urb_packs;
 292         } else if (subs->nurbs < 2) {
 293                 /* too little - we need at least two packets
 294                  * to ensure contiguous playback/capture
 295                  */
 296                 subs->nurbs = 2;
 297         }
 298
 299         /* allocate and initialize data urbs */
 300         for (i = 0; i < subs->nurbs; i++) {
 301                 struct snd_urb_ctx *u = &subs->dataurb[i];
 302                 u->index = i;
 303                 u->subs = subs;
 304                 u->packets = (i + 1) * total_packs / subs->nurbs
 305                         - i * total_packs / subs->nurbs;
 306                 u->buffer_size = maxsize * u->packets;
 307                 if (subs->fmt_type == UAC_FORMAT_TYPE_II)
 308                         u->packets++; /* for transfer delimiter */
 309                 u->urb = usb_alloc_urb(u->packets, GFP_KERNEL);
 310                 if (!u->urb)
 311                         goto out_of_memory;
 312                 u->urb->transfer_buffer =
 313                         usb_alloc_coherent(subs->dev, u->buffer_size,
 314                                            GFP_KERNEL, &u->urb->transfer_dma);
 315                 if (!u->urb->transfer_buffer)
 316                         goto out_of_memory;
 317                 u->urb->pipe = subs->datapipe;
 318                 u->urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
 319                 u->urb->interval = 1 << subs->datainterval;
 320                 u->urb->context = u;
 321                 u->urb->complete = snd_complete_urb;
 322         }
 323
 324         if (subs->syncpipe) {
 325                 /* allocate and initialize sync urbs */
 326                 subs->syncbuf = usb_alloc_coherent(subs->dev, SYNC_URBS * 4,
 327                                                  GFP_KERNEL, &subs->sync_dma);
 328                 if (!subs->syncbuf)
 329                         goto out_of_memory;
 330                 for (i = 0; i < SYNC_URBS; i++) {
 331                         struct snd_urb_ctx *u = &subs->syncurb[i];
 332                         u->index = i;
 333                         u->subs = subs;
 334                         u->packets = 1;
 335                         u->urb = usb_alloc_urb(1, GFP_KERNEL);
 336                         if (!u->urb)
 337                                 goto out_of_memory;
 338                         u->urb->transfer_buffer = subs->syncbuf + i * 4;
 339                         u->urb->transfer_dma = subs->sync_dma + i * 4;
 340                         u->urb->transfer_buffer_length = 4;
 341                         u->urb->pipe = subs->syncpipe;
 342                         u->urb->transfer_flags = URB_ISO_ASAP |
 343                                                  URB_NO_TRANSFER_DMA_MAP;
 344                         u->urb->number_of_packets = 1;
 345                         u->urb->interval = 1 << subs->syncinterval;
 346                         u->urb->context = u;
 347                         u->urb->complete = snd_complete_sync_urb;
 348                 }
 349         }
 350         return 0;
 351
 352 out_of_memory:
 353         snd_usb_release_substream_urbs(subs, 0);
 354         return -ENOMEM;
 355 }
 356
 357 /*
 358  * prepare urb for full speed capture sync pipe
 359  *
 360  * fill the length and offset of each urb descriptor.
 361  * the fixed 10.14 frequency is passed through the pipe.
 362  */
 363 static int prepare_capture_sync_urb(struct snd_usb_substream *subs,
 364                                     struct snd_pcm_runtime *runtime,
 365                                     struct urb *urb)
 366 {
 367         unsigned char *cp = urb->transfer_buffer;
 368         struct snd_urb_ctx *ctx = urb->context;
 369
 370         urb->dev = ctx->subs->dev; /* we need to set this at each time */
 371         urb->iso_frame_desc[0].length = 3;
 372         urb->iso_frame_desc[0].offset = 0;
 373         cp[0] = subs->freqn >> 2;
 374         cp[1] = subs->freqn >> 10;
 375         cp[2] = subs->freqn >> 18;
 376         return 0;
 377 }
 378
 379 /*
 380  * prepare urb for high speed capture sync pipe
 381  *
 382  * fill the length and offset of each urb descriptor.
 383  * the fixed 12.13 frequency is passed as 16.16 through the pipe.
 384  */
 385 static int prepare_capture_sync_urb_hs(struct snd_usb_substream *subs,
 386                                        struct snd_pcm_runtime *runtime,
 387                                        struct urb *urb)
 388 {
 389         unsigned char *cp = urb->transfer_buffer;
 390         struct snd_urb_ctx *ctx = urb->context;
 391
 392         urb->dev = ctx->subs->dev; /* we need to set this at each time */
 393         urb->iso_frame_desc[0].length = 4;
 394         urb->iso_frame_desc[0].offset = 0;
 395         cp[0] = subs->freqn;
 396         cp[1] = subs->freqn >> 8;
 397         cp[2] = subs->freqn >> 16;
 398         cp[3] = subs->freqn >> 24;
 399         return 0;
 400 }
 401
 402 /*
 403  * process after capture sync complete
 404  * - nothing to do
 405  */
 406 static int retire_capture_sync_urb(struct snd_usb_substream *subs,
 407                                    struct snd_pcm_runtime *runtime,
 408                                    struct urb *urb)
 409 {
 410         return 0;
 411 }
 412
 413 /*
 414  * prepare urb for capture data pipe
 415  *
 416  * fill the offset and length of each descriptor.
 417  *
 418  * we use a temporary buffer to write the captured data.
 419  * since the length of written data is determined by host, we cannot
 420  * write onto the pcm buffer directly...  the data is thus copied
 421  * later at complete callback to the global buffer.
 422  */
 423 static int prepare_capture_urb(struct snd_usb_substream *subs,
 424                                struct snd_pcm_runtime *runtime,
 425                                struct urb *urb)
 426 {
 427         int i, offs;
 428         struct snd_urb_ctx *ctx = urb->context;
 429
 430         offs = 0;
 431         urb->dev = ctx->subs->dev; /* we need to set this at each time */
 432         for (i = 0; i < ctx->packets; i++) {
 433                 urb->iso_frame_desc[i].offset = offs;
 434                 urb->iso_frame_desc[i].length = subs->curpacksize;
 435                 offs += subs->curpacksize;
 436         }
 437         urb->transfer_buffer_length = offs;
 438         urb->number_of_packets = ctx->packets;
 439         return 0;
 440 }
 441
 442 /*
 443  * process after capture complete
 444  *
 445  * copy the data from each desctiptor to the pcm buffer, and
 446  * update the current position.
 447  */
 448 static int retire_capture_urb(struct snd_usb_substream *subs,
 449                               struct snd_pcm_runtime *runtime,
 450                               struct urb *urb)
 451 {
 452         unsigned long flags;
 453         unsigned char *cp;
 454         int i;
 455         unsigned int stride, frames, bytes, oldptr;
 456         int period_elapsed = 0;
 457
 458         stride = runtime->frame_bits >> 3;
 459
 460         for (i = 0; i < urb->number_of_packets; i++) {
 461                 cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset;
 462                 if (urb->iso_frame_desc[i].status && printk_ratelimit()) {
 463                         snd_printdd("frame %d active: %d\n", i, urb->iso_frame_desc[i].status);
 464                         // continue;
 465                 }
 466                 bytes = urb->iso_frame_desc[i].actual_length;
 467                 frames = bytes / stride;
 468                 if (!subs->txfr_quirk)
 469                         bytes = frames * stride;
 470                 if (bytes % (runtime->sample_bits >> 3) != 0) {
 471 #ifdef CONFIG_SND_DEBUG_VERBOSE
 472                         int oldbytes = bytes;
 473 #endif
 474                         bytes = frames * stride;
 475                         snd_printdd(KERN_ERR "Corrected urb data len. %d->%d\n",
 476                                                         oldbytes, bytes);
 477                 }
 478                 /* update the current pointer */
 479                 spin_lock_irqsave(&subs->lock, flags);
 480                 oldptr = subs->hwptr_done;
 481                 subs->hwptr_done += bytes;
 482                 if (subs->hwptr_done >= runtime->buffer_size * stride)
 483                         subs->hwptr_done -= runtime->buffer_size * stride;
 484                 frames = (bytes + (oldptr % stride)) / stride;
 485                 subs->transfer_done += frames;
 486                 if (subs->transfer_done >= runtime->period_size) {
 487                         subs->transfer_done -= runtime->period_size;
 488                         period_elapsed = 1;
 489                 }
 490                 spin_unlock_irqrestore(&subs->lock, flags);
 491                 /* copy a data chunk */
 492                 if (oldptr + bytes > runtime->buffer_size * stride) {
 493                         unsigned int bytes1 =
 494                                         runtime->buffer_size * stride - oldptr;
 495                         memcpy(runtime->dma_area + oldptr, cp, bytes1);
 496                         memcpy(runtime->dma_area, cp + bytes1, bytes - bytes1);
 497                 } else {
 498                         memcpy(runtime->dma_area + oldptr, cp, bytes);
 499                 }
 500         }
 501         if (period_elapsed)
 502                 snd_pcm_period_elapsed(subs->pcm_substream);
 503         return 0;
 504 }
 505
 506 /*
 507  * Process after capture complete when paused.  Nothing to do.
 508  */
 509 static int retire_paused_capture_urb(struct snd_usb_substream *subs,
 510                                      struct snd_pcm_runtime *runtime,
 511                                      struct urb *urb)
 512 {
 513         return 0;
 514 }
 515
 516
 517 /*
 518  * prepare urb for playback sync pipe
 519  *
 520  * set up the offset and length to receive the current frequency.
 521  */
 522 static int prepare_playback_sync_urb(struct snd_usb_substream *subs,
 523                                      struct snd_pcm_runtime *runtime,
 524                                      struct urb *urb)
 525 {
 526         struct snd_urb_ctx *ctx = urb->context;
 527
 528         urb->dev = ctx->subs->dev; /* we need to set this at each time */
 529         urb->iso_frame_desc[0].length = min(4u, ctx->subs->syncmaxsize);
 530         urb->iso_frame_desc[0].offset = 0;
 531         return 0;
 532 }
 533
 534 /*
 535  * process after playback sync complete
 536  *
 537  * Full speed devices report feedback values in 10.14 format as samples per
 538  * frame, high speed devices in 16.16 format as samples per microframe.
 539  * Because the Audio Class 1 spec was written before USB 2.0, many high speed
 540  * devices use a wrong interpretation, some others use an entirely different
 541  * format.  Therefore, we cannot predict what format any particular device uses
 542  * and must detect it automatically.
 543  */
 544 static int retire_playback_sync_urb(struct snd_usb_substream *subs,
 545                                     struct snd_pcm_runtime *runtime,
 546                                     struct urb *urb)
 547 {
 548         unsigned int f;
 549         int shift;
 550         unsigned long flags;
 551
 552         if (urb->iso_frame_desc[0].status != 0 ||
 553             urb->iso_frame_desc[0].actual_length < 3)
 554                 return 0;
 555
 556         f = le32_to_cpup(urb->transfer_buffer);
 557         if (urb->iso_frame_desc[0].actual_length == 3)
 558                 f &= 0x00ffffff;
 559         else
 560                 f &= 0x0fffffff;
 561         if (f == 0)
 562                 return 0;
 563
 564         if (unlikely(subs->freqshift == INT_MIN)) {
 565                 /*
 566                  * The first time we see a feedback value, determine its format
 567                  * by shifting it left or right until it matches the nominal
 568                  * frequency value.  This assumes that the feedback does not
 569                  * differ from the nominal value more than +50% or -25%.
 570                  */
 571                 shift = 0;
 572                 while (f < subs->freqn - subs->freqn / 4) {
 573                         f <<= 1;
 574                         shift++;
 575                 }
 576                 while (f > subs->freqn + subs->freqn / 2) {
 577                         f >>= 1;
 578                         shift--;
 579                 }
 580                 subs->freqshift = shift;
 581         }
 582         else if (subs->freqshift >= 0)
 583                 f <<= subs->freqshift;
 584         else
 585                 f >>= -subs->freqshift;
 586
 587         if (likely(f >= subs->freqn - subs->freqn / 8 && f <= subs->freqmax)) {
 588                 /*
 589                  * If the frequency looks valid, set it.
 590                  * This value is referred to in prepare_playback_urb().
 591                  */
 592                 spin_lock_irqsave(&subs->lock, flags);
 593                 subs->freqm = f;
 594                 spin_unlock_irqrestore(&subs->lock, flags);
 595         } else {
 596                 /*
 597                  * Out of range; maybe the shift value is wrong.
 598                  * Reset it so that we autodetect again the next time.
 599                  */
 600                 subs->freqshift = INT_MIN;
 601         }
 602
 603         return 0;
 604 }
 605
 606 /* determine the number of frames in the next packet */
 607 static int snd_usb_audio_next_packet_size(struct snd_usb_substream *subs)
 608 {
 609         if (subs->fill_max)
 610                 return subs->maxframesize;
 611         else {
 612                 subs->phase = (subs->phase & 0xffff)
 613                         + (subs->freqm << subs->datainterval);
 614                 return min(subs->phase >> 16, subs->maxframesize);
 615         }
 616 }
 617
 618 /*
 619  * Prepare urb for streaming before playback starts or when paused.
 620  *
 621  * We don't have any data, so we send silence.
 622  */
 623 static int prepare_nodata_playback_urb(struct snd_usb_substream *subs,
 624                                        struct snd_pcm_runtime *runtime,
 625                                        struct urb *urb)
 626 {
 627         unsigned int i, offs, counts;
 628         struct snd_urb_ctx *ctx = urb->context;
 629         int stride = runtime->frame_bits >> 3;
 630
 631         offs = 0;
 632         urb->dev = ctx->subs->dev;
 633         for (i = 0; i < ctx->packets; ++i) {
 634                 counts = snd_usb_audio_next_packet_size(subs);
 635                 urb->iso_frame_desc[i].offset = offs * stride;
 636                 urb->iso_frame_desc[i].length = counts * stride;
 637                 offs += counts;
 638         }
 639         urb->number_of_packets = ctx->packets;
 640         urb->transfer_buffer_length = offs * stride;
 641         memset(urb->transfer_buffer,
 642                runtime->format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0,
 643                offs * stride);
 644         return 0;
 645 }
 646
 647 /*
 648  * prepare urb for playback data pipe
 649  *
 650  * Since a URB can handle only a single linear buffer, we must use double
 651  * buffering when the data to be transferred overflows the buffer boundary.
 652  * To avoid inconsistencies when updating hwptr_done, we use double buffering
 653  * for all URBs.
 654  */
 655 static int prepare_playback_urb(struct snd_usb_substream *subs,
 656                                 struct snd_pcm_runtime *runtime,
 657                                 struct urb *urb)
 658 {
 659         int i, stride;
 660         unsigned int counts, frames, bytes;
 661         unsigned long flags;
 662         int period_elapsed = 0;
 663         struct snd_urb_ctx *ctx = urb->context;
 664
 665         stride = runtime->frame_bits >> 3;
 666
 667         frames = 0;
 668         urb->dev = ctx->subs->dev; /* we need to set this at each time */
 669         urb->number_of_packets = 0;
 670         spin_lock_irqsave(&subs->lock, flags);
 671         for (i = 0; i < ctx->packets; i++) {
 672                 counts = snd_usb_audio_next_packet_size(subs);
 673                 /* set up descriptor */
 674                 urb->iso_frame_desc[i].offset = frames * stride;
 675                 urb->iso_frame_desc[i].length = counts * stride;
 676                 frames += counts;
 677                 urb->number_of_packets++;
 678                 subs->transfer_done += counts;
 679                 if (subs->transfer_done >= runtime->period_size) {
 680                         subs->transfer_done -= runtime->period_size;
 681                         period_elapsed = 1;
 682                         if (subs->fmt_type == UAC_FORMAT_TYPE_II) {
 683                                 if (subs->transfer_done > 0) {
 684                                         /* FIXME: fill-max mode is not
 685                                          * supported yet */
 686                                         frames -= subs->transfer_done;
 687                                         counts -= subs->transfer_done;
 688                                         urb->iso_frame_desc[i].length =
 689                                                 counts * stride;
 690                                         subs->transfer_done = 0;
 691                                 }
 692                                 i++;
 693                                 if (i < ctx->packets) {
 694                                         /* add a transfer delimiter */
 695                                         urb->iso_frame_desc[i].offset =
 696                                                 frames * stride;
 697                                         urb->iso_frame_desc[i].length = 0;
 698                                         urb->number_of_packets++;
 699                                 }
 700                                 break;
 701                         }
 702                 }
 703                 if (period_elapsed) /* finish at the period boundary */
 704                         break;
 705         }
 706         bytes = frames * stride;
 707         if (subs->hwptr_done + bytes > runtime->buffer_size * stride) {
 708                 /* err, the transferred area goes over buffer boundary. */
 709                 unsigned int bytes1 =
 710                         runtime->buffer_size * stride - subs->hwptr_done;
 711                 memcpy(urb->transfer_buffer,
 712                        runtime->dma_area + subs->hwptr_done, bytes1);
 713                 memcpy(urb->transfer_buffer + bytes1,
 714                        runtime->dma_area, bytes - bytes1);
 715         } else {
 716                 memcpy(urb->transfer_buffer,
 717                        runtime->dma_area + subs->hwptr_done, bytes);
 718         }
 719         subs->hwptr_done += bytes;
 720         if (subs->hwptr_done >= runtime->buffer_size * stride)
 721                 subs->hwptr_done -= runtime->buffer_size * stride;
 722
 723         /* update delay with exact number of samples queued */
 724         runtime->delay = subs->last_delay;
 725         runtime->delay += frames;
 726         subs->last_delay = runtime->delay;
 727
 728         /* realign last_frame_number */
 729         subs->last_frame_number = usb_get_current_frame_number(subs->dev);
 730         subs->last_frame_number &= 0xFF; /* keep 8 LSBs */
 731
 732         spin_unlock_irqrestore(&subs->lock, flags);
 733         urb->transfer_buffer_length = bytes;
 734         if (period_elapsed)
 735                 snd_pcm_period_elapsed(subs->pcm_substream);
 736         return 0;
 737 }
 738
 739 /*
 740  * process after playback data complete
 741  * - decrease the delay count again
 742  */
 743 static int retire_playback_urb(struct snd_usb_substream *subs,
 744                                struct snd_pcm_runtime *runtime,
 745                                struct urb *urb)
 746 {
 747         unsigned long flags;
 748         int stride = runtime->frame_bits >> 3;
 749         int processed = urb->transfer_buffer_length / stride;
 750         int est_delay;
 751
 752         spin_lock_irqsave(&subs->lock, flags);
 753
 754         est_delay = snd_usb_pcm_delay(subs, runtime->rate);
 755         /* update delay with exact number of samples played */
 756         if (processed > subs->last_delay)
 757                 subs->last_delay = 0;
 758         else
 759                 subs->last_delay -= processed;
 760         runtime->delay = subs->last_delay;
 761
 762         /*
 763          * Report when delay estimate is off by more than 2ms.
 764          * The error should be lower than 2ms since the estimate relies
 765          * on two reads of a counter updated every ms.
 766          */
 767         if (abs(est_delay - subs->last_delay) * 1000 > runtime->rate * 2)
 768                 snd_printk(KERN_DEBUG "delay: estimated %d, actual %d\n",
 769                         est_delay, subs->last_delay);
 770
 771         spin_unlock_irqrestore(&subs->lock, flags);
 772         return 0;
 773 }
 774
 775 static const char *usb_error_string(int err)
 776 {
 777         switch (err) {
 778         case -ENODEV:
 779                 return "no device";
 780         case -ENOENT:
 781                 return "endpoint not enabled";
 782         case -EPIPE:
 783                 return "endpoint stalled";
 784         case -ENOSPC:
 785                 return "not enough bandwidth";
 786         case -ESHUTDOWN:
 787                 return "device disabled";
 788         case -EHOSTUNREACH:
 789                 return "device suspended";
 790         case -EINVAL:
 791         case -EAGAIN:
 792         case -EFBIG:
 793         case -EMSGSIZE:
 794                 return "internal error";
 795         default:
 796                 return "unknown error";
 797         }
 798 }
 799
 800 /*
 801  * set up and start data/sync urbs
 802  */
 803 static int start_urbs(struct snd_usb_substream *subs, struct snd_pcm_runtime *runtime)
 804 {
 805         unsigned int i;
 806         int err;
 807
 808         if (subs->stream->chip->shutdown)
 809                 return -EBADFD;
 810
 811         for (i = 0; i < subs->nurbs; i++) {
 812                 if (snd_BUG_ON(!subs->dataurb[i].urb))
 813                         return -EINVAL;
 814                 if (subs->ops.prepare(subs, runtime, subs->dataurb[i].urb) < 0) {
 815                         snd_printk(KERN_ERR "cannot prepare datapipe for urb %d\n", i);
 816                         goto __error;
 817                 }
 818         }
 819         if (subs->syncpipe) {
 820                 for (i = 0; i < SYNC_URBS; i++) {
 821                         if (snd_BUG_ON(!subs->syncurb[i].urb))
 822                                 return -EINVAL;
 823                         if (subs->ops.prepare_sync(subs, runtime, subs->syncurb[i].urb) < 0) {
 824                                 snd_printk(KERN_ERR "cannot prepare syncpipe for urb %d\n", i);
 825                                 goto __error;
 826                         }
 827                 }
 828         }
 829
 830         subs->active_mask = 0;
 831         subs->unlink_mask = 0;
 832         subs->running = 1;
 833         for (i = 0; i < subs->nurbs; i++) {
 834                 err = usb_submit_urb(subs->dataurb[i].urb, GFP_ATOMIC);
 835                 if (err < 0) {
 836                         snd_printk(KERN_ERR "cannot submit datapipe "
 837                                    "for urb %d, error %d: %s\n",
 838                                    i, err, usb_error_string(err));
 839                         goto __error;
 840                 }
 841                 set_bit(i, &subs->active_mask);
 842         }
 843         if (subs->syncpipe) {
 844                 for (i = 0; i < SYNC_URBS; i++) {
 845                         err = usb_submit_urb(subs->syncurb[i].urb, GFP_ATOMIC);
 846                         if (err < 0) {
 847                                 snd_printk(KERN_ERR "cannot submit syncpipe "
 848                                            "for urb %d, error %d: %s\n",
 849                                            i, err, usb_error_string(err));
 850                                 goto __error;
 851                         }
 852                         set_bit(i + 16, &subs->active_mask);
 853                 }
 854         }
 855         return 0;
 856
 857  __error:
 858         // snd_pcm_stop(subs->pcm_substream, SNDRV_PCM_STATE_XRUN);
 859         deactivate_urbs(subs, 0, 0);
 860         return -EPIPE;
 861 }
 862
 863
 864 /*
 865  */
 866 static struct snd_urb_ops audio_urb_ops[2] = {
 867         {
 868                 .prepare =      prepare_nodata_playback_urb,
 869                 .retire =       retire_playback_urb,
 870                 .prepare_sync = prepare_playback_sync_urb,
 871                 .retire_sync =  retire_playback_sync_urb,
 872         },
 873         {
 874                 .prepare =      prepare_capture_urb,
 875                 .retire =       retire_capture_urb,
 876                 .prepare_sync = prepare_capture_sync_urb,
 877                 .retire_sync =  retire_capture_sync_urb,
 878         },
 879 };
 880
 881 /*
 882  * initialize the substream instance.
 883  */
 884
 885 void snd_usb_init_substream(struct snd_usb_stream *as,
 886                             int stream, struct audioformat *fp)
 887 {
 888         struct snd_usb_substream *subs = &as->substream[stream];
 889
 890         INIT_LIST_HEAD(&subs->fmt_list);
 891         spin_lock_init(&subs->lock);
 892
 893         subs->stream = as;
 894         subs->direction = stream;
 895         subs->dev = as->chip->dev;
 896         subs->txfr_quirk = as->chip->txfr_quirk;
 897         subs->ops = audio_urb_ops[stream];
 898         if (snd_usb_get_speed(subs->dev) >= USB_SPEED_HIGH)
 899                 subs->ops.prepare_sync = prepare_capture_sync_urb_hs;
 900
 901         snd_usb_set_pcm_ops(as->pcm, stream);
 902
 903         list_add_tail(&fp->list, &subs->fmt_list);
 904         subs->formats |= fp->formats;
 905         subs->endpoint = fp->endpoint;
 906         subs->num_formats++;
 907         subs->fmt_type = fp->fmt_type;
 908 }
 909
 910 int snd_usb_substream_playback_trigger(struct snd_pcm_substream *substream, int cmd)
 911 {
 912         struct snd_usb_substream *subs = substream->runtime->private_data;
 913
 914         switch (cmd) {
 915         case SNDRV_PCM_TRIGGER_START:
 916         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 917                 subs->ops.prepare = prepare_playback_urb;
 918                 return 0;
 919         case SNDRV_PCM_TRIGGER_STOP:
 920                 return deactivate_urbs(subs, 0, 0);
 921         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 922                 subs->ops.prepare = prepare_nodata_playback_urb;
 923                 return 0;
 924         }
 925
 926         return -EINVAL;
 927 }
 928
 929 int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream, int cmd)
 930 {
 931         struct snd_usb_substream *subs = substream->runtime->private_data;
 932
 933         switch (cmd) {
 934         case SNDRV_PCM_TRIGGER_START:
 935                 subs->ops.retire = retire_capture_urb;
 936                 return start_urbs(subs, substream->runtime);
 937         case SNDRV_PCM_TRIGGER_STOP:
 938                 return deactivate_urbs(subs, 0, 0);
 939         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 940                 subs->ops.retire = retire_paused_capture_urb;
 941                 return 0;
 942         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 943                 subs->ops.retire = retire_capture_urb;
 944                 return 0;
 945         }
 946
 947         return -EINVAL;
 948 }
 949
 950 int snd_usb_substream_prepare(struct snd_usb_substream *subs,
 951                               struct snd_pcm_runtime *runtime)
 952 {
 953         /* clear urbs (to be sure) */
 954         deactivate_urbs(subs, 0, 1);
 955         wait_clear_urbs(subs);
 956
 957         /* for playback, submit the URBs now; otherwise, the first hwptr_done
 958          * updates for all URBs would happen at the same time when starting */
 959         if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK) {
 960                 subs->ops.prepare = prepare_nodata_playback_urb;
 961                 return start_urbs(subs, runtime);
 962         }
 963
 964         return 0;
 965 }
 966