git.oblomov.eu Git - linux-2.6/blob - sound/drivers/pcm-indirect2.c

   1 /*
   2  * Helper functions for indirect PCM data transfer to a simple FIFO in
   3  * hardware (small, no possibility to read "hardware io position",
   4  * updating position done by interrupt, ...)
   5  *
   6  *  Copyright (c) by 2007  Joachim Foerster <JOFT@gmx.de>
   7  *
   8  *  Based on "pcm-indirect.h" (alsa-driver-1.0.13) by
   9  *
  10  *  Copyright (c) by Takashi Iwai <tiwai@suse.de>
  11  *                   Jaroslav Kysela <perex@suse.cz>
  12  *
  13  *   This program is free software; you can redistribute it and/or modify
  14  *   it under the terms of the GNU General Public License as published by
  15  *   the Free Software Foundation; either version 2 of the License, or
  16  *   (at your option) any later version.
  17  *
  18  *   This program is distributed in the hope that it will be useful,
  19  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  *   GNU General Public License for more details.
  22  *
  23  *   You should have received a copy of the GNU General Public License
  24  *   along with this program; if not, write to the Free Software
  25  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  26  */
  27
  28 /* snd_printk/d() */
  29 #include <sound/core.h>
  30 /* struct snd_pcm_substream, struct snd_pcm_runtime, snd_pcm_uframes_t
  31  * snd_pcm_period_elapsed() */
  32 #include <sound/pcm.h>
  33
  34 #include "pcm-indirect2.h"
  35
  36 #ifdef SND_PCM_INDIRECT2_STAT
  37 /* jiffies */
  38 #include <linux/jiffies.h>
  39
  40 void snd_pcm_indirect2_stat(struct snd_pcm_substream *substream,
  41                             struct snd_pcm_indirect2 *rec)
  42 {
  43         struct snd_pcm_runtime *runtime = substream->runtime;
  44         int i;
  45         int j;
  46         int k;
  47         int seconds = (rec->lastbytetime - rec->firstbytetime) / HZ;
  48
  49         snd_printk(KERN_DEBUG "STAT: mul_elapsed: %u, mul_elapsed_real: %d, "
  50                    "irq_occured: %d\n",
  51                    rec->mul_elapsed, rec->mul_elapsed_real, rec->irq_occured);
  52         snd_printk(KERN_DEBUG "STAT: min_multiple: %d (irqs/period)\n",
  53                    rec->min_multiple);
  54         snd_printk(KERN_DEBUG "STAT: firstbytetime: %lu, lastbytetime: %lu, "
  55                    "firstzerotime: %lu\n",
  56                  rec->firstbytetime, rec->lastbytetime, rec->firstzerotime);
  57         snd_printk(KERN_DEBUG "STAT: bytes2hw: %u Bytes => (by runtime->rate) "
  58                    "length: %d s\n",
  59                  rec->bytes2hw, rec->bytes2hw / 2 / 2 / runtime->rate);
  60         snd_printk(KERN_DEBUG "STAT: (by measurement) length: %d => "
  61                    "rate: %d Bytes/s = %d Frames/s|Hz\n",
  62                    seconds, rec->bytes2hw / seconds,
  63                    rec->bytes2hw / 2 / 2 / seconds);
  64         snd_printk(KERN_DEBUG
  65                    "STAT: zeros2hw: %u = %d ms ~ %d * %d zero copies\n",
  66                    rec->zeros2hw, ((rec->zeros2hw / 2 / 2) * 1000) /
  67                    runtime->rate,
  68                    rec->zeros2hw / (rec->hw_buffer_size / 2),
  69                    (rec->hw_buffer_size / 2));
  70         snd_printk(KERN_DEBUG "STAT: pointer_calls: %u, lastdifftime: %u\n",
  71                    rec->pointer_calls, rec->lastdifftime);
  72         snd_printk(KERN_DEBUG "STAT: sw_io: %d, sw_data: %d\n", rec->sw_io,
  73                    rec->sw_data);
  74         snd_printk(KERN_DEBUG "STAT: byte_sizes[]:\n");
  75         k = 0;
  76         for (j = 0; j < 8; j++) {
  77                 for (i = j * 8; i < (j + 1) * 8; i++)
  78                         if (rec->byte_sizes[i] != 0) {
  79                                 snd_printk(KERN_DEBUG "%u: %u",
  80                                            i, rec->byte_sizes[i]);
  81                                 k++;
  82                         }
  83                 if (((k % 8) == 0) && (k != 0)) {
  84                         snd_printk(KERN_DEBUG "\n");
  85                         k = 0;
  86                 }
  87         }
  88         snd_printk(KERN_DEBUG "\n");
  89         snd_printk(KERN_DEBUG "STAT: zero_sizes[]:\n");
  90         for (j = 0; j < 8; j++) {
  91                 k = 0;
  92                 for (i = j * 8; i < (j + 1) * 8; i++)
  93                         if (rec->zero_sizes[i] != 0)
  94                                 snd_printk(KERN_DEBUG "%u: %u",
  95                                            i, rec->zero_sizes[i]);
  96                         else
  97                                 k++;
  98                 if (!k)
  99                         snd_printk(KERN_DEBUG "\n");
 100         }
 101         snd_printk(KERN_DEBUG "\n");
 102         snd_printk(KERN_DEBUG "STAT: min_adds[]:\n");
 103         for (j = 0; j < 8; j++) {
 104                 if (rec->min_adds[j] != 0)
 105                         snd_printk(KERN_DEBUG "%u: %u", j, rec->min_adds[j]);
 106         }
 107         snd_printk(KERN_DEBUG "\n");
 108         snd_printk(KERN_DEBUG "STAT: mul_adds[]:\n");
 109         for (j = 0; j < 8; j++) {
 110                 if (rec->mul_adds[j] != 0)
 111                         snd_printk(KERN_DEBUG "%u: %u", j, rec->mul_adds[j]);
 112         }
 113         snd_printk(KERN_DEBUG "\n");
 114         snd_printk(KERN_DEBUG
 115                    "STAT: zero_times_saved: %d, zero_times_notsaved: %d\n",
 116                    rec->zero_times_saved, rec->zero_times_notsaved);
 117         /* snd_printk(KERN_DEBUG "STAT: zero_times[]\n");
 118         i = 0;
 119         for (j = 0; j < 3750; j++) {
 120                 if (rec->zero_times[j] != 0) {
 121                         snd_printk(KERN_DEBUG "%u: %u", j, rec->zero_times[j]);
 122                         i++;
 123                 }
 124                 if (((i % 8) == 0) && (i != 0))
 125                         snd_printk(KERN_DEBUG "\n");
 126         }
 127         snd_printk(KERN_DEBUG "\n"); */
 128         return;
 129 }
 130 #endif
 131
 132 /*
 133  * _internal_ helper function for playback/capture transfer function
 134  */
 135 static void
 136 snd_pcm_indirect2_increase_min_periods(struct snd_pcm_substream *substream,
 137                                        struct snd_pcm_indirect2 *rec,
 138                                        int isplay, int iscopy,
 139                                        unsigned int bytes)
 140 {
 141         if (rec->min_periods >= 0) {
 142                 if (iscopy) {
 143                         rec->sw_io += bytes;
 144                         if (rec->sw_io >= rec->sw_buffer_size)
 145                                 rec->sw_io -= rec->sw_buffer_size;
 146                 } else if (isplay) {
 147                         /* If application does not write data in multiples of
 148                          * a period, move sw_data to the next correctly aligned
 149                          * position, so that sw_io can converge to it (in the
 150                          * next step).
 151                          */
 152                         if (!rec->check_alignment) {
 153                                 if (rec->bytes2hw %
 154                                     snd_pcm_lib_period_bytes(substream)) {
 155                                         unsigned bytes2hw_aligned =
 156                                             (1 +
 157                                              (rec->bytes2hw /
 158                                               snd_pcm_lib_period_bytes
 159                                               (substream))) *
 160                                             snd_pcm_lib_period_bytes
 161                                             (substream);
 162                                         rec->sw_data =
 163                                             bytes2hw_aligned %
 164                                             rec->sw_buffer_size;
 165 #ifdef SND_PCM_INDIRECT2_STAT
 166                                         snd_printk(KERN_DEBUG
 167                                                    "STAT: @re-align: aligned "
 168                                                    "bytes2hw to next period "
 169                                                    "size boundary: %d "
 170                                                    "(instead of %d)\n",
 171                                                    bytes2hw_aligned,
 172                                                    rec->bytes2hw);
 173                                         snd_printk(KERN_DEBUG
 174                                                    "STAT: @re-align: sw_data "
 175                                                    "moves to: %d\n",
 176                                                    rec->sw_data);
 177 #endif
 178                                 }
 179                                 rec->check_alignment = 1;
 180                         }
 181                         /* We are at the end and are copying zeros into the
 182                          * fifo.
 183                          * Now, we have to make sure that sw_io is increased
 184                          * until the position of sw_data: Filling the fifo with
 185                          * the first zeros means, the last bytes were played.
 186                          */
 187                         if (rec->sw_io != rec->sw_data) {
 188                                 unsigned int diff;
 189                                 if (rec->sw_data > rec->sw_io)
 190                                         diff = rec->sw_data - rec->sw_io;
 191                                 else
 192                                         diff = (rec->sw_buffer_size -
 193                                                 rec->sw_io) +
 194                                                 rec->sw_data;
 195                                 if (bytes >= diff)
 196                                         rec->sw_io = rec->sw_data;
 197                                 else {
 198                                         rec->sw_io += bytes;
 199                                         if (rec->sw_io >= rec->sw_buffer_size)
 200                                                 rec->sw_io -=
 201                                                     rec->sw_buffer_size;
 202                                 }
 203                         }
 204                 }
 205                 rec->min_period_count += bytes;
 206                 if (rec->min_period_count >= (rec->hw_buffer_size / 2)) {
 207                         rec->min_periods += (rec->min_period_count /
 208                                              (rec->hw_buffer_size / 2));
 209 #ifdef SND_PCM_INDIRECT2_STAT
 210                         if ((rec->min_period_count /
 211                              (rec->hw_buffer_size / 2)) > 7)
 212                                 snd_printk(KERN_DEBUG
 213                                            "STAT: more than 7 (%d) min_adds "
 214                                            "at once - too big to save!\n",
 215                                            (rec->min_period_count /
 216                                             (rec->hw_buffer_size / 2)));
 217                         else
 218                                 rec->min_adds[(rec->min_period_count /
 219                                                (rec->hw_buffer_size / 2))]++;
 220 #endif
 221                         rec->min_period_count = (rec->min_period_count %
 222                                                  (rec->hw_buffer_size / 2));
 223                 }
 224         } else if (isplay && iscopy)
 225                 rec->min_periods = 0;
 226 }
 227
 228 /*
 229  * helper function for playback/capture pointer callback
 230  */
 231 snd_pcm_uframes_t
 232 snd_pcm_indirect2_pointer(struct snd_pcm_substream *substream,
 233                           struct snd_pcm_indirect2 *rec)
 234 {
 235 #ifdef SND_PCM_INDIRECT2_STAT
 236         rec->pointer_calls++;
 237 #endif
 238         return bytes_to_frames(substream->runtime, rec->sw_io);
 239 }
 240
 241 /*
 242  * _internal_ helper function for playback interrupt callback
 243  */
 244 static void
 245 snd_pcm_indirect2_playback_transfer(struct snd_pcm_substream *substream,
 246                                     struct snd_pcm_indirect2 *rec,
 247                                     snd_pcm_indirect2_copy_t copy,
 248                                     snd_pcm_indirect2_zero_t zero)
 249 {
 250         struct snd_pcm_runtime *runtime = substream->runtime;
 251         snd_pcm_uframes_t appl_ptr = runtime->control->appl_ptr;
 252
 253         /* runtime->control->appl_ptr: position where ALSA will write next time
 254          * rec->appl_ptr: position where ALSA was last time
 255          * diff: obviously ALSA wrote that much bytes into the intermediate
 256          * buffer since we checked last time
 257          */
 258         snd_pcm_sframes_t diff = appl_ptr - rec->appl_ptr;
 259
 260         if (diff) {
 261 #ifdef SND_PCM_INDIRECT2_STAT
 262                 rec->lastdifftime = jiffies;
 263 #endif
 264                 if (diff < -(snd_pcm_sframes_t) (runtime->boundary / 2))
 265                         diff += runtime->boundary;
 266                 /* number of bytes "added" by ALSA increases the number of
 267                  * bytes which are ready to "be transfered to HW"/"played"
 268                  * Then, set rec->appl_ptr to not count bytes twice next time.
 269                  */
 270                 rec->sw_ready += (int)frames_to_bytes(runtime, diff);
 271                 rec->appl_ptr = appl_ptr;
 272         }
 273         if (rec->hw_ready && (rec->sw_ready <= 0)) {
 274                 unsigned int bytes;
 275
 276 #ifdef SND_PCM_INDIRECT2_STAT
 277                 if (rec->firstzerotime == 0) {
 278                         rec->firstzerotime = jiffies;
 279                         snd_printk(KERN_DEBUG
 280                                    "STAT: @firstzerotime: mul_elapsed: %d, "
 281                                    "min_period_count: %d\n",
 282                                    rec->mul_elapsed, rec->min_period_count);
 283                         snd_printk(KERN_DEBUG
 284                                    "STAT: @firstzerotime: sw_io: %d, "
 285                                    "sw_data: %d, appl_ptr: %u\n",
 286                                    rec->sw_io, rec->sw_data,
 287                                    (unsigned int)appl_ptr);
 288                 }
 289                 if ((jiffies - rec->firstzerotime) < 3750) {
 290                         rec->zero_times[(jiffies - rec->firstzerotime)]++;
 291                         rec->zero_times_saved++;
 292                 } else
 293                         rec->zero_times_notsaved++;
 294 #endif
 295                 bytes = zero(substream, rec);
 296
 297 #ifdef SND_PCM_INDIRECT2_STAT
 298                 rec->zeros2hw += bytes;
 299                 if (bytes < 64)
 300                         rec->zero_sizes[bytes]++;
 301                 else
 302                         snd_printk(KERN_DEBUG
 303                                    "STAT: %d zero Bytes copied to hardware at "
 304                                    "once - too big to save!\n",
 305                                    bytes);
 306 #endif
 307                 snd_pcm_indirect2_increase_min_periods(substream, rec, 1, 0,
 308                                                        bytes);
 309                 return;
 310         }
 311         while (rec->hw_ready && (rec->sw_ready > 0)) {
 312                 /* sw_to_end: max. number of bytes that can be read/take from
 313                  * the current position (sw_data) in _one_ step
 314                  */
 315                 unsigned int sw_to_end = rec->sw_buffer_size - rec->sw_data;
 316
 317                 /* bytes: number of bytes we have available (for reading) */
 318                 unsigned int bytes = rec->sw_ready;
 319
 320                 if (sw_to_end < bytes)
 321                         bytes = sw_to_end;
 322                 if (!bytes)
 323                         break;
 324
 325 #ifdef SND_PCM_INDIRECT2_STAT
 326                 if (rec->firstbytetime == 0)
 327                         rec->firstbytetime = jiffies;
 328                 rec->lastbytetime = jiffies;
 329 #endif
 330                 /* copy bytes from intermediate buffer position sw_data to the
 331                  * HW and return number of bytes actually written
 332                  * Furthermore, set hw_ready to 0, if the fifo isn't empty
 333                  * now => more could be transfered to fifo
 334                  */
 335                 bytes = copy(substream, rec, bytes);
 336                 rec->bytes2hw += bytes;
 337
 338 #ifdef SND_PCM_INDIRECT2_STAT
 339                 if (bytes < 64)
 340                         rec->byte_sizes[bytes]++;
 341                 else
 342                         snd_printk(KERN_DEBUG
 343                                    "STAT: %d Bytes copied to hardware at once "
 344                                    "- too big to save!\n",
 345                                    bytes);
 346 #endif
 347                 /* increase sw_data by the number of actually written bytes
 348                  * (= number of taken bytes from intermediate buffer)
 349                  */
 350                 rec->sw_data += bytes;
 351                 if (rec->sw_data == rec->sw_buffer_size)
 352                         rec->sw_data = 0;
 353                 /* now sw_data is the position where ALSA is going to write
 354                  * in the intermediate buffer next time = position we are going
 355                  * to read from next time
 356                  */
 357
 358                 snd_pcm_indirect2_increase_min_periods(substream, rec, 1, 1,
 359                                                        bytes);
 360
 361                 /* we read bytes from intermediate buffer, so we need to say
 362                  * that the number of bytes ready for transfer are decreased
 363                  * now
 364                  */
 365                 rec->sw_ready -= bytes;
 366         }
 367         return;
 368 }
 369
 370 /*
 371  * helper function for playback interrupt routine
 372  */
 373 void
 374 snd_pcm_indirect2_playback_interrupt(struct snd_pcm_substream *substream,
 375                                      struct snd_pcm_indirect2 *rec,
 376                                      snd_pcm_indirect2_copy_t copy,
 377                                      snd_pcm_indirect2_zero_t zero)
 378 {
 379 #ifdef SND_PCM_INDIRECT2_STAT
 380         rec->irq_occured++;
 381 #endif
 382         /* hardware played some bytes, so there is room again (in fifo) */
 383         rec->hw_ready = 1;
 384
 385         /* don't call ack() now, instead call transfer() function directly
 386          * (normally called by ack() )
 387          */
 388         snd_pcm_indirect2_playback_transfer(substream, rec, copy, zero);
 389
 390         if (rec->min_periods >= rec->min_multiple) {
 391 #ifdef SND_PCM_INDIRECT2_STAT
 392                 if ((rec->min_periods / rec->min_multiple) > 7)
 393                         snd_printk(KERN_DEBUG
 394                                    "STAT: more than 7 (%d) mul_adds - too big "
 395                                    "to save!\n",
 396                                    (rec->min_periods / rec->min_multiple));
 397                 else
 398                         rec->mul_adds[(rec->min_periods /
 399                                        rec->min_multiple)]++;
 400                 rec->mul_elapsed_real += (rec->min_periods /
 401                                           rec->min_multiple);
 402                 rec->mul_elapsed++;
 403 #endif
 404                 rec->min_periods = (rec->min_periods % rec->min_multiple);
 405                 snd_pcm_period_elapsed(substream);
 406         }
 407 }
 408
 409 /*
 410  * _internal_ helper function for capture interrupt callback
 411  */
 412 static void
 413 snd_pcm_indirect2_capture_transfer(struct snd_pcm_substream *substream,
 414                                    struct snd_pcm_indirect2 *rec,
 415                                    snd_pcm_indirect2_copy_t copy,
 416                                    snd_pcm_indirect2_zero_t null)
 417 {
 418         struct snd_pcm_runtime *runtime = substream->runtime;
 419         snd_pcm_uframes_t appl_ptr = runtime->control->appl_ptr;
 420         snd_pcm_sframes_t diff = appl_ptr - rec->appl_ptr;
 421
 422         if (diff) {
 423 #ifdef SND_PCM_INDIRECT2_STAT
 424                 rec->lastdifftime = jiffies;
 425 #endif
 426                 if (diff < -(snd_pcm_sframes_t) (runtime->boundary / 2))
 427                         diff += runtime->boundary;
 428                 rec->sw_ready -= frames_to_bytes(runtime, diff);
 429                 rec->appl_ptr = appl_ptr;
 430         }
 431         /* if hardware has something, but the intermediate buffer is full
 432          * => skip contents of buffer
 433          */
 434         if (rec->hw_ready && (rec->sw_ready >= (int)rec->sw_buffer_size)) {
 435                 unsigned int bytes;
 436
 437 #ifdef SND_PCM_INDIRECT2_STAT
 438                 if (rec->firstzerotime == 0) {
 439                         rec->firstzerotime = jiffies;
 440                         snd_printk(KERN_DEBUG "STAT: (capture) "
 441                                    "@firstzerotime: mul_elapsed: %d, "
 442                                    "min_period_count: %d\n",
 443                                    rec->mul_elapsed, rec->min_period_count);
 444                         snd_printk(KERN_DEBUG "STAT: (capture) "
 445                                    "@firstzerotime: sw_io: %d, sw_data: %d, "
 446                                    "appl_ptr: %u\n",
 447                                    rec->sw_io, rec->sw_data,
 448                                    (unsigned int)appl_ptr);
 449                 }
 450                 if ((jiffies - rec->firstzerotime) < 3750) {
 451                         rec->zero_times[(jiffies - rec->firstzerotime)]++;
 452                         rec->zero_times_saved++;
 453                 } else
 454                         rec->zero_times_notsaved++;
 455 #endif
 456                 bytes = null(substream, rec);
 457
 458 #ifdef SND_PCM_INDIRECT2_STAT
 459                 rec->zeros2hw += bytes;
 460                 if (bytes < 64)
 461                         rec->zero_sizes[bytes]++;
 462                 else
 463                         snd_printk(KERN_DEBUG
 464                                    "STAT: (capture) %d zero Bytes copied to "
 465                                    "hardware at once - too big to save!\n",
 466                                    bytes);
 467 #endif
 468                 snd_pcm_indirect2_increase_min_periods(substream, rec, 0, 0,
 469                                                        bytes);
 470                 /* report an overrun */
 471                 rec->sw_io = SNDRV_PCM_POS_XRUN;
 472                 return;
 473         }
 474         while (rec->hw_ready && (rec->sw_ready < (int)rec->sw_buffer_size)) {
 475                 /* sw_to_end: max. number of bytes that we can write to the
 476                  *  intermediate buffer (until it's end)
 477                  */
 478                 size_t sw_to_end = rec->sw_buffer_size - rec->sw_data;
 479
 480                 /* bytes: max. number of bytes, which may be copied to the
 481                  *  intermediate buffer without overflow (in _one_ step)
 482                  */
 483                 size_t bytes = rec->sw_buffer_size - rec->sw_ready;
 484
 485                 /* limit number of bytes (for transfer) by available room in
 486                  * the intermediate buffer
 487                  */
 488                 if (sw_to_end < bytes)
 489                         bytes = sw_to_end;
 490                 if (!bytes)
 491                         break;
 492
 493 #ifdef SND_PCM_INDIRECT2_STAT
 494                 if (rec->firstbytetime == 0)
 495                         rec->firstbytetime = jiffies;
 496                 rec->lastbytetime = jiffies;
 497 #endif
 498                 /* copy bytes from the intermediate buffer (position sw_data)
 499                  * to the HW at most and return number of bytes actually copied
 500                  * from HW
 501                  * Furthermore, set hw_ready to 0, if the fifo is empty now.
 502                  */
 503                 bytes = copy(substream, rec, bytes);
 504                 rec->bytes2hw += bytes;
 505
 506 #ifdef SND_PCM_INDIRECT2_STAT
 507                 if (bytes < 64)
 508                         rec->byte_sizes[bytes]++;
 509                 else
 510                         snd_printk(KERN_DEBUG
 511                                    "STAT: (capture) %d Bytes copied to "
 512                                    "hardware at once - too big to save!\n",
 513                                    bytes);
 514 #endif
 515                 /* increase sw_data by the number of actually copied bytes from
 516                  * HW
 517                  */
 518                 rec->sw_data += bytes;
 519                 if (rec->sw_data == rec->sw_buffer_size)
 520                         rec->sw_data = 0;
 521
 522                 snd_pcm_indirect2_increase_min_periods(substream, rec, 0, 1,
 523                                                        bytes);
 524
 525                 /* number of bytes in the intermediate buffer, which haven't
 526                  * been fetched by ALSA yet.
 527                  */
 528                 rec->sw_ready += bytes;
 529         }
 530         return;
 531 }
 532
 533 /*
 534  * helper function for capture interrupt routine
 535  */
 536 void
 537 snd_pcm_indirect2_capture_interrupt(struct snd_pcm_substream *substream,
 538                                     struct snd_pcm_indirect2 *rec,
 539                                     snd_pcm_indirect2_copy_t copy,
 540                                     snd_pcm_indirect2_zero_t null)
 541 {
 542 #ifdef SND_PCM_INDIRECT2_STAT
 543         rec->irq_occured++;
 544 #endif
 545         /* hardware recorded some bytes, so there is something to read from the
 546          * record fifo:
 547          */
 548         rec->hw_ready = 1;
 549
 550         /* don't call ack() now, instead call transfer() function directly
 551          * (normally called by ack() )
 552          */
 553         snd_pcm_indirect2_capture_transfer(substream, rec, copy, null);
 554
 555         if (rec->min_periods >= rec->min_multiple) {
 556
 557 #ifdef SND_PCM_INDIRECT2_STAT
 558                 if ((rec->min_periods / rec->min_multiple) > 7)
 559                         snd_printk(KERN_DEBUG
 560                                    "STAT: more than 7 (%d) mul_adds - "
 561                                    "too big to save!\n",
 562                                    (rec->min_periods / rec->min_multiple));
 563                 else
 564                         rec->mul_adds[(rec->min_periods /
 565                                        rec->min_multiple)]++;
 566                 rec->mul_elapsed_real += (rec->min_periods /
 567                                           rec->min_multiple);
 568                 rec->mul_elapsed++;
 569 #endif
 570                 rec->min_periods = (rec->min_periods % rec->min_multiple);
 571                 snd_pcm_period_elapsed(substream);
 572         }
 573 }