git.oblomov.eu Git - linux-2.6/blob - sound/core/oss/pcm_plugin.c

   1 /*
   2  *  PCM Plug-In shared (kernel/library) code
   3  *  Copyright (c) 1999 by Jaroslav Kysela <perex@suse.cz>
   4  *  Copyright (c) 2000 by Abramo Bagnara <abramo@alsa-project.org>
   5  *
   6  *
   7  *   This library is free software; you can redistribute it and/or modify
   8  *   it under the terms of the GNU Library General Public License as
   9  *   published by the Free Software Foundation; either version 2 of
  10  *   the License, or (at your option) any later version.
  11  *
  12  *   This program is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU Library General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU Library General Public
  18  *   License along with this library; if not, write to the Free Software
  19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  20  *
  21  */
  22
  23 #if 0
  24 #define PLUGIN_DEBUG
  25 #endif
  26
  27 #include <sound/driver.h>
  28
  29 #ifdef CONFIG_SND_PCM_OSS_PLUGINS
  30
  31 #include <linux/slab.h>
  32 #include <linux/time.h>
  33 #include <linux/vmalloc.h>
  34 #include <sound/core.h>
  35 #include <sound/pcm.h>
  36 #include <sound/pcm_params.h>
  37 #include "pcm_plugin.h"
  38
  39 #define snd_pcm_plug_first(plug) ((plug)->runtime->oss.plugin_first)
  40 #define snd_pcm_plug_last(plug) ((plug)->runtime->oss.plugin_last)
  41
  42 /*
  43  *  because some cards might have rates "very close", we ignore
  44  *  all "resampling" requests within +-5%
  45  */
  46 static int rate_match(unsigned int src_rate, unsigned int dst_rate)
  47 {
  48         unsigned int low = (src_rate * 95) / 100;
  49         unsigned int high = (src_rate * 105) / 100;
  50         return dst_rate >= low && dst_rate <= high;
  51 }
  52
  53 static int snd_pcm_plugin_alloc(struct snd_pcm_plugin *plugin, snd_pcm_uframes_t frames)
  54 {
  55         struct snd_pcm_plugin_format *format;
  56         ssize_t width;
  57         size_t size;
  58         unsigned int channel;
  59         struct snd_pcm_plugin_channel *c;
  60
  61         if (plugin->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  62                 format = &plugin->src_format;
  63         } else {
  64                 format = &plugin->dst_format;
  65         }
  66         if ((width = snd_pcm_format_physical_width(format->format)) < 0)
  67                 return width;
  68         size = frames * format->channels * width;
  69         snd_assert((size % 8) == 0, return -ENXIO);
  70         size /= 8;
  71         if (plugin->buf_frames < frames) {
  72                 vfree(plugin->buf);
  73                 plugin->buf = vmalloc(size);
  74                 plugin->buf_frames = frames;
  75         }
  76         if (!plugin->buf) {
  77                 plugin->buf_frames = 0;
  78                 return -ENOMEM;
  79         }
  80         c = plugin->buf_channels;
  81         if (plugin->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED) {
  82                 for (channel = 0; channel < format->channels; channel++, c++) {
  83                         c->frames = frames;
  84                         c->enabled = 1;
  85                         c->wanted = 0;
  86                         c->area.addr = plugin->buf;
  87                         c->area.first = channel * width;
  88                         c->area.step = format->channels * width;
  89                 }
  90         } else if (plugin->access == SNDRV_PCM_ACCESS_RW_NONINTERLEAVED) {
  91                 snd_assert((size % format->channels) == 0,);
  92                 size /= format->channels;
  93                 for (channel = 0; channel < format->channels; channel++, c++) {
  94                         c->frames = frames;
  95                         c->enabled = 1;
  96                         c->wanted = 0;
  97                         c->area.addr = plugin->buf + (channel * size);
  98                         c->area.first = 0;
  99                         c->area.step = width;
 100                 }
 101         } else
 102                 return -EINVAL;
 103         return 0;
 104 }
 105
 106 int snd_pcm_plug_alloc(struct snd_pcm_substream *plug, snd_pcm_uframes_t frames)
 107 {
 108         int err;
 109         snd_assert(snd_pcm_plug_first(plug) != NULL, return -ENXIO);
 110         if (snd_pcm_plug_stream(plug) == SNDRV_PCM_STREAM_PLAYBACK) {
 111                 struct snd_pcm_plugin *plugin = snd_pcm_plug_first(plug);
 112                 while (plugin->next) {
 113                         if (plugin->dst_frames)
 114                                 frames = plugin->dst_frames(plugin, frames);
 115                         snd_assert(frames > 0, return -ENXIO);
 116                         plugin = plugin->next;
 117                         err = snd_pcm_plugin_alloc(plugin, frames);
 118                         if (err < 0)
 119                                 return err;
 120                 }
 121         } else {
 122                 struct snd_pcm_plugin *plugin = snd_pcm_plug_last(plug);
 123                 while (plugin->prev) {
 124                         if (plugin->src_frames)
 125                                 frames = plugin->src_frames(plugin, frames);
 126                         snd_assert(frames > 0, return -ENXIO);
 127                         plugin = plugin->prev;
 128                         err = snd_pcm_plugin_alloc(plugin, frames);
 129                         if (err < 0)
 130                                 return err;
 131                 }
 132         }
 133         return 0;
 134 }
 135
 136
 137 snd_pcm_sframes_t snd_pcm_plugin_client_channels(struct snd_pcm_plugin *plugin,
 138                                        snd_pcm_uframes_t frames,
 139                                        struct snd_pcm_plugin_channel **channels)
 140 {
 141         *channels = plugin->buf_channels;
 142         return frames;
 143 }
 144
 145 int snd_pcm_plugin_build(struct snd_pcm_substream *plug,
 146                          const char *name,
 147                          struct snd_pcm_plugin_format *src_format,
 148                          struct snd_pcm_plugin_format *dst_format,
 149                          size_t extra,
 150                          struct snd_pcm_plugin **ret)
 151 {
 152         struct snd_pcm_plugin *plugin;
 153         unsigned int channels;
 154
 155         snd_assert(plug != NULL, return -ENXIO);
 156         snd_assert(src_format != NULL && dst_format != NULL, return -ENXIO);
 157         plugin = kzalloc(sizeof(*plugin) + extra, GFP_KERNEL);
 158         if (plugin == NULL)
 159                 return -ENOMEM;
 160         plugin->name = name;
 161         plugin->plug = plug;
 162         plugin->stream = snd_pcm_plug_stream(plug);
 163         plugin->access = SNDRV_PCM_ACCESS_RW_INTERLEAVED;
 164         plugin->src_format = *src_format;
 165         plugin->src_width = snd_pcm_format_physical_width(src_format->format);
 166         snd_assert(plugin->src_width > 0, );
 167         plugin->dst_format = *dst_format;
 168         plugin->dst_width = snd_pcm_format_physical_width(dst_format->format);
 169         snd_assert(plugin->dst_width > 0, );
 170         if (plugin->stream == SNDRV_PCM_STREAM_PLAYBACK)
 171                 channels = src_format->channels;
 172         else
 173                 channels = dst_format->channels;
 174         plugin->buf_channels = kcalloc(channels, sizeof(*plugin->buf_channels), GFP_KERNEL);
 175         if (plugin->buf_channels == NULL) {
 176                 snd_pcm_plugin_free(plugin);
 177                 return -ENOMEM;
 178         }
 179         plugin->client_channels = snd_pcm_plugin_client_channels;
 180         *ret = plugin;
 181         return 0;
 182 }
 183
 184 int snd_pcm_plugin_free(struct snd_pcm_plugin *plugin)
 185 {
 186         if (! plugin)
 187                 return 0;
 188         if (plugin->private_free)
 189                 plugin->private_free(plugin);
 190         kfree(plugin->buf_channels);
 191         vfree(plugin->buf);
 192         kfree(plugin);
 193         return 0;
 194 }
 195
 196 snd_pcm_sframes_t snd_pcm_plug_client_size(struct snd_pcm_substream *plug, snd_pcm_uframes_t drv_frames)
 197 {
 198         struct snd_pcm_plugin *plugin, *plugin_prev, *plugin_next;
 199         int stream = snd_pcm_plug_stream(plug);
 200
 201         snd_assert(plug != NULL, return -ENXIO);
 202         if (drv_frames == 0)
 203                 return 0;
 204         if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
 205                 plugin = snd_pcm_plug_last(plug);
 206                 while (plugin && drv_frames > 0) {
 207                         plugin_prev = plugin->prev;
 208                         if (plugin->src_frames)
 209                                 drv_frames = plugin->src_frames(plugin, drv_frames);
 210                         plugin = plugin_prev;
 211                 }
 212         } else if (stream == SNDRV_PCM_STREAM_CAPTURE) {
 213                 plugin = snd_pcm_plug_first(plug);
 214                 while (plugin && drv_frames > 0) {
 215                         plugin_next = plugin->next;
 216                         if (plugin->dst_frames)
 217                                 drv_frames = plugin->dst_frames(plugin, drv_frames);
 218                         plugin = plugin_next;
 219                 }
 220         } else
 221                 snd_BUG();
 222         return drv_frames;
 223 }
 224
 225 snd_pcm_sframes_t snd_pcm_plug_slave_size(struct snd_pcm_substream *plug, snd_pcm_uframes_t clt_frames)
 226 {
 227         struct snd_pcm_plugin *plugin, *plugin_prev, *plugin_next;
 228         snd_pcm_sframes_t frames;
 229         int stream = snd_pcm_plug_stream(plug);
 230
 231         snd_assert(plug != NULL, return -ENXIO);
 232         if (clt_frames == 0)
 233                 return 0;
 234         frames = clt_frames;
 235         if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
 236                 plugin = snd_pcm_plug_first(plug);
 237                 while (plugin && frames > 0) {
 238                         plugin_next = plugin->next;
 239                         if (plugin->dst_frames) {
 240                                 frames = plugin->dst_frames(plugin, frames);
 241                                 if (frames < 0)
 242                                         return frames;
 243                         }
 244                         plugin = plugin_next;
 245                 }
 246         } else if (stream == SNDRV_PCM_STREAM_CAPTURE) {
 247                 plugin = snd_pcm_plug_last(plug);
 248                 while (plugin) {
 249                         plugin_prev = plugin->prev;
 250                         if (plugin->src_frames) {
 251                                 frames = plugin->src_frames(plugin, frames);
 252                                 if (frames < 0)
 253                                         return frames;
 254                         }
 255                         plugin = plugin_prev;
 256                 }
 257         } else
 258                 snd_BUG();
 259         return frames;
 260 }
 261
 262 static int snd_pcm_plug_formats(struct snd_mask *mask, int format)
 263 {
 264         struct snd_mask formats = *mask;
 265         u64 linfmts = (SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S8 |
 266                        SNDRV_PCM_FMTBIT_U16_LE | SNDRV_PCM_FMTBIT_S16_LE |
 267                        SNDRV_PCM_FMTBIT_U16_BE | SNDRV_PCM_FMTBIT_S16_BE |
 268                        SNDRV_PCM_FMTBIT_U24_LE | SNDRV_PCM_FMTBIT_S24_LE |
 269                        SNDRV_PCM_FMTBIT_U24_BE | SNDRV_PCM_FMTBIT_S24_BE |
 270                        SNDRV_PCM_FMTBIT_U32_LE | SNDRV_PCM_FMTBIT_S32_LE |
 271                        SNDRV_PCM_FMTBIT_U32_BE | SNDRV_PCM_FMTBIT_S32_BE);
 272         snd_mask_set(&formats, SNDRV_PCM_FORMAT_MU_LAW);
 273
 274         if (formats.bits[0] & (u32)linfmts)
 275                 formats.bits[0] |= (u32)linfmts;
 276         if (formats.bits[1] & (u32)(linfmts >> 32))
 277                 formats.bits[1] |= (u32)(linfmts >> 32);
 278         return snd_mask_test(&formats, format);
 279 }
 280
 281 static int preferred_formats[] = {
 282         SNDRV_PCM_FORMAT_S16_LE,
 283         SNDRV_PCM_FORMAT_S16_BE,
 284         SNDRV_PCM_FORMAT_U16_LE,
 285         SNDRV_PCM_FORMAT_U16_BE,
 286         SNDRV_PCM_FORMAT_S24_LE,
 287         SNDRV_PCM_FORMAT_S24_BE,
 288         SNDRV_PCM_FORMAT_U24_LE,
 289         SNDRV_PCM_FORMAT_U24_BE,
 290         SNDRV_PCM_FORMAT_S32_LE,
 291         SNDRV_PCM_FORMAT_S32_BE,
 292         SNDRV_PCM_FORMAT_U32_LE,
 293         SNDRV_PCM_FORMAT_U32_BE,
 294         SNDRV_PCM_FORMAT_S8,
 295         SNDRV_PCM_FORMAT_U8
 296 };
 297
 298 int snd_pcm_plug_slave_format(int format, struct snd_mask *format_mask)
 299 {
 300         if (snd_mask_test(format_mask, format))
 301                 return format;
 302         if (! snd_pcm_plug_formats(format_mask, format))
 303                 return -EINVAL;
 304         if (snd_pcm_format_linear(format)) {
 305                 int width = snd_pcm_format_width(format);
 306                 int unsignd = snd_pcm_format_unsigned(format);
 307                 int big = snd_pcm_format_big_endian(format);
 308                 int format1;
 309                 int wid, width1=width;
 310                 int dwidth1 = 8;
 311                 for (wid = 0; wid < 4; ++wid) {
 312                         int end, big1 = big;
 313                         for (end = 0; end < 2; ++end) {
 314                                 int sgn, unsignd1 = unsignd;
 315                                 for (sgn = 0; sgn < 2; ++sgn) {
 316                                         format1 = snd_pcm_build_linear_format(width1, unsignd1, big1);
 317                                         if (format1 >= 0 &&
 318                                             snd_mask_test(format_mask, format1))
 319                                                 goto _found;
 320                                         unsignd1 = !unsignd1;
 321                                 }
 322                                 big1 = !big1;
 323                         }
 324                         if (width1 == 32) {
 325                                 dwidth1 = -dwidth1;
 326                                 width1 = width;
 327                         }
 328                         width1 += dwidth1;
 329                 }
 330                 return -EINVAL;
 331         _found:
 332                 return format1;
 333         } else {
 334                 unsigned int i;
 335                 switch (format) {
 336                 case SNDRV_PCM_FORMAT_MU_LAW:
 337                         for (i = 0; i < ARRAY_SIZE(preferred_formats); ++i) {
 338                                 int format1 = preferred_formats[i];
 339                                 if (snd_mask_test(format_mask, format1))
 340                                         return format1;
 341                         }
 342                 default:
 343                         return -EINVAL;
 344                 }
 345         }
 346 }
 347
 348 int snd_pcm_plug_format_plugins(struct snd_pcm_substream *plug,
 349                                 struct snd_pcm_hw_params *params,
 350                                 struct snd_pcm_hw_params *slave_params)
 351 {
 352         struct snd_pcm_plugin_format tmpformat;
 353         struct snd_pcm_plugin_format dstformat;
 354         struct snd_pcm_plugin_format srcformat;
 355         int src_access, dst_access;
 356         struct snd_pcm_plugin *plugin = NULL;
 357         int err;
 358         int stream = snd_pcm_plug_stream(plug);
 359         int slave_interleaved = (params_channels(slave_params) == 1 ||
 360                                  params_access(slave_params) == SNDRV_PCM_ACCESS_RW_INTERLEAVED);
 361
 362         switch (stream) {
 363         case SNDRV_PCM_STREAM_PLAYBACK:
 364                 dstformat.format = params_format(slave_params);
 365                 dstformat.rate = params_rate(slave_params);
 366                 dstformat.channels = params_channels(slave_params);
 367                 srcformat.format = params_format(params);
 368                 srcformat.rate = params_rate(params);
 369                 srcformat.channels = params_channels(params);
 370                 src_access = SNDRV_PCM_ACCESS_RW_INTERLEAVED;
 371                 dst_access = (slave_interleaved ? SNDRV_PCM_ACCESS_RW_INTERLEAVED :
 372                                                   SNDRV_PCM_ACCESS_RW_NONINTERLEAVED);
 373                 break;
 374         case SNDRV_PCM_STREAM_CAPTURE:
 375                 dstformat.format = params_format(params);
 376                 dstformat.rate = params_rate(params);
 377                 dstformat.channels = params_channels(params);
 378                 srcformat.format = params_format(slave_params);
 379                 srcformat.rate = params_rate(slave_params);
 380                 srcformat.channels = params_channels(slave_params);
 381                 src_access = (slave_interleaved ? SNDRV_PCM_ACCESS_RW_INTERLEAVED :
 382                                                   SNDRV_PCM_ACCESS_RW_NONINTERLEAVED);
 383                 dst_access = SNDRV_PCM_ACCESS_RW_INTERLEAVED;
 384                 break;
 385         default:
 386                 snd_BUG();
 387                 return -EINVAL;
 388         }
 389         tmpformat = srcformat;
 390
 391         pdprintf("srcformat: format=%i, rate=%i, channels=%i\n",
 392                  srcformat.format,
 393                  srcformat.rate,
 394                  srcformat.channels);
 395         pdprintf("dstformat: format=%i, rate=%i, channels=%i\n",
 396                  dstformat.format,
 397                  dstformat.rate,
 398                  dstformat.channels);
 399
 400         /* Format change (linearization) */
 401         if (! rate_match(srcformat.rate, dstformat.rate) &&
 402             ! snd_pcm_format_linear(srcformat.format)) {
 403                 if (srcformat.format != SNDRV_PCM_FORMAT_MU_LAW)
 404                         return -EINVAL;
 405                 tmpformat.format = SNDRV_PCM_FORMAT_S16;
 406                 err = snd_pcm_plugin_build_mulaw(plug,
 407                                                  &srcformat, &tmpformat,
 408                                                  &plugin);
 409                 if (err < 0)
 410                         return err;
 411                 err = snd_pcm_plugin_append(plugin);
 412                 if (err < 0) {
 413                         snd_pcm_plugin_free(plugin);
 414                         return err;
 415                 }
 416                 srcformat = tmpformat;
 417                 src_access = dst_access;
 418         }
 419
 420         /* channels reduction */
 421         if (srcformat.channels > dstformat.channels) {
 422                 tmpformat.channels = dstformat.channels;
 423                 err = snd_pcm_plugin_build_route(plug, &srcformat, &tmpformat, &plugin);
 424                 pdprintf("channels reduction: src=%i, dst=%i returns %i\n", srcformat.channels, tmpformat.channels, err);
 425                 if (err < 0)
 426                         return err;
 427                 err = snd_pcm_plugin_append(plugin);
 428                 if (err < 0) {
 429                         snd_pcm_plugin_free(plugin);
 430                         return err;
 431                 }
 432                 srcformat = tmpformat;
 433                 src_access = dst_access;
 434         }
 435
 436         /* rate resampling */
 437         if (!rate_match(srcformat.rate, dstformat.rate)) {
 438                 if (srcformat.format != SNDRV_PCM_FORMAT_S16) {
 439                         /* convert to S16 for resampling */
 440                         tmpformat.format = SNDRV_PCM_FORMAT_S16;
 441                         err = snd_pcm_plugin_build_linear(plug,
 442                                                           &srcformat, &tmpformat,
 443                                                           &plugin);
 444                         if (err < 0)
 445                                 return err;
 446                         err = snd_pcm_plugin_append(plugin);
 447                         if (err < 0) {
 448                                 snd_pcm_plugin_free(plugin);
 449                                 return err;
 450                         }
 451                         srcformat = tmpformat;
 452                         src_access = dst_access;
 453                 }
 454                 tmpformat.rate = dstformat.rate;
 455                 err = snd_pcm_plugin_build_rate(plug,
 456                                                 &srcformat, &tmpformat,
 457                                                 &plugin);
 458                 pdprintf("rate down resampling: src=%i, dst=%i returns %i\n", srcformat.rate, tmpformat.rate, err);
 459                 if (err < 0)
 460                         return err;
 461                 err = snd_pcm_plugin_append(plugin);
 462                 if (err < 0) {
 463                         snd_pcm_plugin_free(plugin);
 464                         return err;
 465                 }
 466                 srcformat = tmpformat;
 467                 src_access = dst_access;
 468         }
 469
 470         /* format change */
 471         if (srcformat.format != dstformat.format) {
 472                 tmpformat.format = dstformat.format;
 473                 if (srcformat.format == SNDRV_PCM_FORMAT_MU_LAW ||
 474                     tmpformat.format == SNDRV_PCM_FORMAT_MU_LAW) {
 475                         err = snd_pcm_plugin_build_mulaw(plug,
 476                                                          &srcformat, &tmpformat,
 477                                                          &plugin);
 478                 }
 479                 else if (snd_pcm_format_linear(srcformat.format) &&
 480                          snd_pcm_format_linear(tmpformat.format)) {
 481                         err = snd_pcm_plugin_build_linear(plug,
 482                                                           &srcformat, &tmpformat,
 483                                                           &plugin);
 484                 }
 485                 else
 486                         return -EINVAL;
 487                 pdprintf("format change: src=%i, dst=%i returns %i\n", srcformat.format, tmpformat.format, err);
 488                 if (err < 0)
 489                         return err;
 490                 err = snd_pcm_plugin_append(plugin);
 491                 if (err < 0) {
 492                         snd_pcm_plugin_free(plugin);
 493                         return err;
 494                 }
 495                 srcformat = tmpformat;
 496                 src_access = dst_access;
 497         }
 498
 499         /* channels extension */
 500         if (srcformat.channels < dstformat.channels) {
 501                 tmpformat.channels = dstformat.channels;
 502                 err = snd_pcm_plugin_build_route(plug, &srcformat, &tmpformat, &plugin);
 503                 pdprintf("channels extension: src=%i, dst=%i returns %i\n", srcformat.channels, tmpformat.channels, err);
 504                 if (err < 0)
 505                         return err;
 506                 err = snd_pcm_plugin_append(plugin);
 507                 if (err < 0) {
 508                         snd_pcm_plugin_free(plugin);
 509                         return err;
 510                 }
 511                 srcformat = tmpformat;
 512                 src_access = dst_access;
 513         }
 514
 515         /* de-interleave */
 516         if (src_access != dst_access) {
 517                 err = snd_pcm_plugin_build_copy(plug,
 518                                                 &srcformat,
 519                                                 &tmpformat,
 520                                                 &plugin);
 521                 pdprintf("interleave change (copy: returns %i)\n", err);
 522                 if (err < 0)
 523                         return err;
 524                 err = snd_pcm_plugin_append(plugin);
 525                 if (err < 0) {
 526                         snd_pcm_plugin_free(plugin);
 527                         return err;
 528                 }
 529         }
 530
 531         return 0;
 532 }
 533
 534 snd_pcm_sframes_t snd_pcm_plug_client_channels_buf(struct snd_pcm_substream *plug,
 535                                          char *buf,
 536                                          snd_pcm_uframes_t count,
 537                                          struct snd_pcm_plugin_channel **channels)
 538 {
 539         struct snd_pcm_plugin *plugin;
 540         struct snd_pcm_plugin_channel *v;
 541         struct snd_pcm_plugin_format *format;
 542         int width, nchannels, channel;
 543         int stream = snd_pcm_plug_stream(plug);
 544
 545         snd_assert(buf != NULL, return -ENXIO);
 546         if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
 547                 plugin = snd_pcm_plug_first(plug);
 548                 format = &plugin->src_format;
 549         } else {
 550                 plugin = snd_pcm_plug_last(plug);
 551                 format = &plugin->dst_format;
 552         }
 553         v = plugin->buf_channels;
 554         *channels = v;
 555         if ((width = snd_pcm_format_physical_width(format->format)) < 0)
 556                 return width;
 557         nchannels = format->channels;
 558         snd_assert(plugin->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED || format->channels <= 1, return -ENXIO);
 559         for (channel = 0; channel < nchannels; channel++, v++) {
 560                 v->frames = count;
 561                 v->enabled = 1;
 562                 v->wanted = (stream == SNDRV_PCM_STREAM_CAPTURE);
 563                 v->area.addr = buf;
 564                 v->area.first = channel * width;
 565                 v->area.step = nchannels * width;
 566         }
 567         return count;
 568 }
 569
 570 snd_pcm_sframes_t snd_pcm_plug_write_transfer(struct snd_pcm_substream *plug, struct snd_pcm_plugin_channel *src_channels, snd_pcm_uframes_t size)
 571 {
 572         struct snd_pcm_plugin *plugin, *next;
 573         struct snd_pcm_plugin_channel *dst_channels;
 574         int err;
 575         snd_pcm_sframes_t frames = size;
 576
 577         plugin = snd_pcm_plug_first(plug);
 578         while (plugin && frames > 0) {
 579                 if ((next = plugin->next) != NULL) {
 580                         snd_pcm_sframes_t frames1 = frames;
 581                         if (plugin->dst_frames)
 582                                 frames1 = plugin->dst_frames(plugin, frames);
 583                         if ((err = next->client_channels(next, frames1, &dst_channels)) < 0) {
 584                                 return err;
 585                         }
 586                         if (err != frames1) {
 587                                 frames = err;
 588                                 if (plugin->src_frames)
 589                                         frames = plugin->src_frames(plugin, frames1);
 590                         }
 591                 } else
 592                         dst_channels = NULL;
 593                 pdprintf("write plugin: %s, %li\n", plugin->name, frames);
 594                 if ((frames = plugin->transfer(plugin, src_channels, dst_channels, frames)) < 0)
 595                         return frames;
 596                 src_channels = dst_channels;
 597                 plugin = next;
 598         }
 599         return snd_pcm_plug_client_size(plug, frames);
 600 }
 601
 602 snd_pcm_sframes_t snd_pcm_plug_read_transfer(struct snd_pcm_substream *plug, struct snd_pcm_plugin_channel *dst_channels_final, snd_pcm_uframes_t size)
 603 {
 604         struct snd_pcm_plugin *plugin, *next;
 605         struct snd_pcm_plugin_channel *src_channels, *dst_channels;
 606         snd_pcm_sframes_t frames = size;
 607         int err;
 608
 609         frames = snd_pcm_plug_slave_size(plug, frames);
 610         if (frames < 0)
 611                 return frames;
 612
 613         src_channels = NULL;
 614         plugin = snd_pcm_plug_first(plug);
 615         while (plugin && frames > 0) {
 616                 if ((next = plugin->next) != NULL) {
 617                         if ((err = plugin->client_channels(plugin, frames, &dst_channels)) < 0) {
 618                                 return err;
 619                         }
 620                         frames = err;
 621                 } else {
 622                         dst_channels = dst_channels_final;
 623                 }
 624                 pdprintf("read plugin: %s, %li\n", plugin->name, frames);
 625                 if ((frames = plugin->transfer(plugin, src_channels, dst_channels, frames)) < 0)
 626                         return frames;
 627                 plugin = next;
 628                 src_channels = dst_channels;
 629         }
 630         return frames;
 631 }
 632
 633 int snd_pcm_area_silence(const struct snd_pcm_channel_area *dst_area, size_t dst_offset,
 634                          size_t samples, int format)
 635 {
 636         /* FIXME: sub byte resolution and odd dst_offset */
 637         unsigned char *dst;
 638         unsigned int dst_step;
 639         int width;
 640         const unsigned char *silence;
 641         if (!dst_area->addr)
 642                 return 0;
 643         dst = dst_area->addr + (dst_area->first + dst_area->step * dst_offset) / 8;
 644         width = snd_pcm_format_physical_width(format);
 645         if (width <= 0)
 646                 return -EINVAL;
 647         if (dst_area->step == (unsigned int) width && width >= 8)
 648                 return snd_pcm_format_set_silence(format, dst, samples);
 649         silence = snd_pcm_format_silence_64(format);
 650         if (! silence)
 651                 return -EINVAL;
 652         dst_step = dst_area->step / 8;
 653         if (width == 4) {
 654                 /* Ima ADPCM */
 655                 int dstbit = dst_area->first % 8;
 656                 int dstbit_step = dst_area->step % 8;
 657                 while (samples-- > 0) {
 658                         if (dstbit)
 659                                 *dst &= 0xf0;
 660                         else
 661                                 *dst &= 0x0f;
 662                         dst += dst_step;
 663                         dstbit += dstbit_step;
 664                         if (dstbit == 8) {
 665                                 dst++;
 666                                 dstbit = 0;
 667                         }
 668                 }
 669         } else {
 670                 width /= 8;
 671                 while (samples-- > 0) {
 672                         memcpy(dst, silence, width);
 673                         dst += dst_step;
 674                 }
 675         }
 676         return 0;
 677 }
 678
 679 int snd_pcm_area_copy(const struct snd_pcm_channel_area *src_area, size_t src_offset,
 680                       const struct snd_pcm_channel_area *dst_area, size_t dst_offset,
 681                       size_t samples, int format)
 682 {
 683         /* FIXME: sub byte resolution and odd dst_offset */
 684         char *src, *dst;
 685         int width;
 686         int src_step, dst_step;
 687         src = src_area->addr + (src_area->first + src_area->step * src_offset) / 8;
 688         if (!src_area->addr)
 689                 return snd_pcm_area_silence(dst_area, dst_offset, samples, format);
 690         dst = dst_area->addr + (dst_area->first + dst_area->step * dst_offset) / 8;
 691         if (!dst_area->addr)
 692                 return 0;
 693         width = snd_pcm_format_physical_width(format);
 694         if (width <= 0)
 695                 return -EINVAL;
 696         if (src_area->step == (unsigned int) width &&
 697             dst_area->step == (unsigned int) width && width >= 8) {
 698                 size_t bytes = samples * width / 8;
 699                 memcpy(dst, src, bytes);
 700                 return 0;
 701         }
 702         src_step = src_area->step / 8;
 703         dst_step = dst_area->step / 8;
 704         if (width == 4) {
 705                 /* Ima ADPCM */
 706                 int srcbit = src_area->first % 8;
 707                 int srcbit_step = src_area->step % 8;
 708                 int dstbit = dst_area->first % 8;
 709                 int dstbit_step = dst_area->step % 8;
 710                 while (samples-- > 0) {
 711                         unsigned char srcval;
 712                         if (srcbit)
 713                                 srcval = *src & 0x0f;
 714                         else
 715                                 srcval = (*src & 0xf0) >> 4;
 716                         if (dstbit)
 717                                 *dst = (*dst & 0xf0) | srcval;
 718                         else
 719                                 *dst = (*dst & 0x0f) | (srcval << 4);
 720                         src += src_step;
 721                         srcbit += srcbit_step;
 722                         if (srcbit == 8) {
 723                                 src++;
 724                                 srcbit = 0;
 725                         }
 726                         dst += dst_step;
 727                         dstbit += dstbit_step;
 728                         if (dstbit == 8) {
 729                                 dst++;
 730                                 dstbit = 0;
 731                         }
 732                 }
 733         } else {
 734                 width /= 8;
 735                 while (samples-- > 0) {
 736                         memcpy(dst, src, width);
 737                         src += src_step;
 738                         dst += dst_step;
 739                 }
 740         }
 741         return 0;
 742 }
 743
 744 #endif