sound/core/oss/pcm_plugin.c

   1 /*
   2  *  PCM Plug-In shared (kernel/library) code
   3  *  Copyright (c) 1999 by Jaroslav Kysela <perex@perex.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 <linux/slab.h>
  28 #include <linux/time.h>
  29 #include <linux/vmalloc.h>
  30 #include <sound/core.h>
  31 #include <sound/pcm.h>
  32 #include <sound/pcm_params.h>
  33 #include "pcm_plugin.h"
  34
  35 #define snd_pcm_plug_first(plug) ((plug)->runtime->oss.plugin_first)
  36 #define snd_pcm_plug_last(plug) ((plug)->runtime->oss.plugin_last)
  37
  38 /*
  39  *  because some cards might have rates "very close", we ignore
  40  *  all "resampling" requests within +-5%
  41  */
  42 static int rate_match(unsigned int src_rate, unsigned int dst_rate)
  43 {
  44         unsigned int low = (src_rate * 95) / 100;
  45         unsigned int high = (src_rate * 105) / 100;
  46         return dst_rate >= low && dst_rate <= high;
  47 }
  48
  49 static int snd_pcm_plugin_alloc(struct snd_pcm_plugin *plugin, snd_pcm_uframes_t frames)
  50 {
  51         struct snd_pcm_plugin_format *format;
  52         ssize_t width;
  53         size_t size;
  54         unsigned int channel;
  55         struct snd_pcm_plugin_channel *c;
  56
  57         if (plugin->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  58                 format = &plugin->src_format;
  59         } else {
  60                 format = &plugin->dst_format;
  61         }
  62         if ((width = snd_pcm_format_physical_width(format->format)) < 0)
  63                 return width;
  64         size = frames * format->channels * width;
  65         if (snd_BUG_ON(size % 8))
  66                 return -ENXIO;
  67         size /= 8;
  68         if (plugin->buf_frames < frames) {
  69                 vfree(plugin->buf);
  70                 plugin->buf = vmalloc(size);
  71                 plugin->buf_frames = frames;
  72         }
  73         if (!plugin->buf) {
  74                 plugin->buf_frames = 0;
  75                 return -ENOMEM;
  76         }
  77         c = plugin->buf_channels;
  78         if (plugin->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED) {
  79                 for (channel = 0; channel < format->channels; channel++, c++) {
  80                         c->frames = frames;
  81                         c->enabled = 1;
  82                         c->wanted = 0;
  83                         c->area.addr = plugin->buf;
  84                         c->area.first = channel * width;
  85                         c->area.step = format->channels * width;
  86                 }
  87         } else if (plugin->access == SNDRV_PCM_ACCESS_RW_NONINTERLEAVED) {
  88                 if (snd_BUG_ON(size % format->channels))
  89                         return -EINVAL;
  90                 size /= format->channels;
  91                 for (channel = 0; channel < format->channels; channel++, c++) {
  92                         c->frames = frames;
  93                         c->enabled = 1;
  94                         c->wanted = 0;
  95                         c->area.addr = plugin->buf + (channel * size);
  96                         c->area.first = 0;
  97                         c->area.step = width;
  98                 }
  99         } else
 100                 return -EINVAL;
 101         return 0;
 102 }
 103
 104 int snd_pcm_plug_alloc(struct snd_pcm_substream *plug, snd_pcm_uframes_t frames)
 105 {
 106         int err;
 107         if (snd_BUG_ON(!snd_pcm_plug_first(plug)))
 108                 return -ENXIO;
 109         if (snd_pcm_plug_stream(plug) == SNDRV_PCM_STREAM_PLAYBACK) {
 110                 struct snd_pcm_plugin *plugin = snd_pcm_plug_first(plug);
 111                 while (plugin->next) {
 112                         if (plugin->dst_frames)
 113                                 frames = plugin->dst_frames(plugin, frames);
 114                         if (snd_BUG_ON(frames <= 0))
 115                                 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                         if (snd_BUG_ON(frames <= 0))
 127                                 return -ENXIO;
 128                         plugin = plugin->prev;
 129                         err = snd_pcm_plugin_alloc(plugin, frames);
 130                         if (err < 0)
 131                                 return err;
 132                 }
 133         }
 134         return 0;
 135 }
 136
 137
 138 snd_pcm_sframes_t snd_pcm_plugin_client_channels(struct snd_pcm_plugin *plugin,
 139                                        snd_pcm_uframes_t frames,
 140                                        struct snd_pcm_plugin_channel **channels)
 141 {
 142         *channels = plugin->buf_channels;
 143         return frames;
 144 }
 145
 146 int snd_pcm_plugin_build(struct snd_pcm_substream *plug,
 147                          const char *name,
 148                          struct snd_pcm_plugin_format *src_format,
 149                          struct snd_pcm_plugin_format *dst_format,
 150                          size_t extra,
 151                          struct snd_pcm_plugin **ret)
 152 {
 153         struct snd_pcm_plugin *plugin;
 154         unsigned int channels;
 155
 156         if (snd_BUG_ON(!plug))
 157                 return -ENXIO;
 158         if (snd_BUG_ON(!src_format || !dst_format))
 159                 return -ENXIO;
 160         plugin = kzalloc(sizeof(*plugin) + extra, GFP_KERNEL);
 161         if (plugin == NULL)
 162                 return -ENOMEM;
 163         plugin->name = name;
 164         plugin->plug = plug;
 165         plugin->stream = snd_pcm_plug_stream(plug);
 166         plugin->access = SNDRV_PCM_ACCESS_RW_INTERLEAVED;
 167         plugin->src_format = *src_format;
 168         plugin->src_width = snd_pcm_format_physical_width(src_format->format);
 169         snd_BUG_ON(plugin->src_width <= 0);
 170         plugin->dst_format = *dst_format;
 171         plugin->dst_width = snd_pcm_format_physical_width(dst_format->format);
 172         snd_BUG_ON(plugin->dst_width <= 0);
 173         if (plugin->stream == SNDRV_PCM_STREAM_PLAYBACK)
 174                 channels = src_format->channels;
 175         else
 176                 channels = dst_format->channels;
 177         plugin->buf_channels = kcalloc(channels, sizeof(*plugin->buf_channels), GFP_KERNEL);
 178         if (plugin->buf_channels == NULL) {
 179                 snd_pcm_plugin_free(plugin);
 180                 return -ENOMEM;
 181         }
 182         plugin->client_channels = snd_pcm_plugin_client_channels;
 183         *ret = plugin;
 184         return 0;
 185 }
 186
 187 int snd_pcm_plugin_free(struct snd_pcm_plugin *plugin)
 188 {
 189         if (! plugin)
 190                 return 0;
 191         if (plugin->private_free)
 192                 plugin->private_free(plugin);
 193         kfree(plugin->buf_channels);
 194         vfree(plugin->buf);
 195         kfree(plugin);
 196         return 0;
 197 }
 198
 199 snd_pcm_sframes_t snd_pcm_plug_client_size(struct snd_pcm_substream *plug, snd_pcm_uframes_t drv_frames)
 200 {
 201         struct snd_pcm_plugin *plugin, *plugin_prev, *plugin_next;
 202         int stream = snd_pcm_plug_stream(plug);
 203
 204         if (snd_BUG_ON(!plug))
 205                 return -ENXIO;
 206         if (drv_frames == 0)
 207                 return 0;
 208         if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
 209                 plugin = snd_pcm_plug_last(plug);
 210                 while (plugin && drv_frames > 0) {
 211                         plugin_prev = plugin->prev;
 212                         if (plugin->src_frames)
 213                                 drv_frames = plugin->src_frames(plugin, drv_frames);
 214                         plugin = plugin_prev;
 215                 }
 216         } else if (stream == SNDRV_PCM_STREAM_CAPTURE) {
 217                 plugin = snd_pcm_plug_first(plug);
 218                 while (plugin && drv_frames > 0) {
 219                         plugin_next = plugin->next;
 220                         if (plugin->dst_frames)
 221                                 drv_frames = plugin->dst_frames(plugin, drv_frames);
 222                         plugin = plugin_next;
 223                 }
 224         } else
 225                 snd_BUG();
 226         return drv_frames;
 227 }
 228
 229 snd_pcm_sframes_t snd_pcm_plug_slave_size(struct snd_pcm_substream *plug, snd_pcm_uframes_t clt_frames)
 230 {
 231         struct snd_pcm_plugin *plugin, *plugin_prev, *plugin_next;
 232         snd_pcm_sframes_t frames;
 233         int stream = snd_pcm_plug_stream(plug);
 234
 235         if (snd_BUG_ON(!plug))
 236                 return -ENXIO;
 237         if (clt_frames == 0)
 238                 return 0;
 239         frames = clt_frames;
 240         if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
 241                 plugin = snd_pcm_plug_first(plug);
 242                 while (plugin && frames > 0) {
 243                         plugin_next = plugin->next;
 244                         if (plugin->dst_frames) {
 245                                 frames = plugin->dst_frames(plugin, frames);
 246                                 if (frames < 0)
 247                                         return frames;
 248                         }
 249                         plugin = plugin_next;
 250                 }
 251         } else if (stream == SNDRV_PCM_STREAM_CAPTURE) {
 252                 plugin = snd_pcm_plug_last(plug);
 253                 while (plugin) {
 254                         plugin_prev = plugin->prev;
 255                         if (plugin->src_frames) {
 256                                 frames = plugin->src_frames(plugin, frames);
 257                                 if (frames < 0)
 258                                         return frames;
 259                         }
 260                         plugin = plugin_prev;
 261                 }
 262         } else
 263                 snd_BUG();
 264         return frames;
 265 }
 266
 267 static int snd_pcm_plug_formats(struct snd_mask *mask, snd_pcm_format_t format)
 268 {
 269         struct snd_mask formats = *mask;
 270         u64 linfmts = (SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S8 |
 271                        SNDRV_PCM_FMTBIT_U16_LE | SNDRV_PCM_FMTBIT_S16_LE |
 272                        SNDRV_PCM_FMTBIT_U16_BE | SNDRV_PCM_FMTBIT_S16_BE |
 273                        SNDRV_PCM_FMTBIT_U24_LE | SNDRV_PCM_FMTBIT_S24_LE |
 274                        SNDRV_PCM_FMTBIT_U24_BE | SNDRV_PCM_FMTBIT_S24_BE |
 275                        SNDRV_PCM_FMTBIT_U24_3LE | SNDRV_PCM_FMTBIT_S24_3LE |
 276                        SNDRV_PCM_FMTBIT_U24_3BE | SNDRV_PCM_FMTBIT_S24_3BE |
 277                        SNDRV_PCM_FMTBIT_U32_LE | SNDRV_PCM_FMTBIT_S32_LE |
 278                        SNDRV_PCM_FMTBIT_U32_BE | SNDRV_PCM_FMTBIT_S32_BE);
 279         snd_mask_set(&formats, (__force int)SNDRV_PCM_FORMAT_MU_LAW);
 280
 281         if (formats.bits[0] & (u32)linfmts)
 282                 formats.bits[0] |= (u32)linfmts;
 283         if (formats.bits[1] & (u32)(linfmts >> 32))
 284                 formats.bits[1] |= (u32)(linfmts >> 32);
 285         return snd_mask_test(&formats, (__force int)format);
 286 }
 287
 288 static snd_pcm_format_t preferred_formats[] = {
 289         SNDRV_PCM_FORMAT_S16_LE,
 290         SNDRV_PCM_FORMAT_S16_BE,
 291         SNDRV_PCM_FORMAT_U16_LE,
 292         SNDRV_PCM_FORMAT_U16_BE,
 293         SNDRV_PCM_FORMAT_S24_3LE,
 294         SNDRV_PCM_FORMAT_S24_3BE,
 295         SNDRV_PCM_FORMAT_U24_3LE,
 296         SNDRV_PCM_FORMAT_U24_3BE,
 297         SNDRV_PCM_FORMAT_S24_LE,
 298         SNDRV_PCM_FORMAT_S24_BE,
 299         SNDRV_PCM_FORMAT_U24_LE,
 300         SNDRV_PCM_FORMAT_U24_BE,
 301         SNDRV_PCM_FORMAT_S32_LE,
 302         SNDRV_PCM_FORMAT_S32_BE,
 303         SNDRV_PCM_FORMAT_U32_LE,
 304         SNDRV_PCM_FORMAT_U32_BE,
 305         SNDRV_PCM_FORMAT_S8,
 306         SNDRV_PCM_FORMAT_U8
 307 };
 308
 309 snd_pcm_format_t snd_pcm_plug_slave_format(snd_pcm_format_t format,
 310                                            struct snd_mask *format_mask)
 311 {
 312         int i;
 313
 314         if (snd_mask_test(format_mask, (__force int)format))
 315                 return format;
 316         if (!snd_pcm_plug_formats(format_mask, format))
 317                 return (__force snd_pcm_format_t)-EINVAL;
 318         if (snd_pcm_format_linear(format)) {
 319                 unsigned int width = snd_pcm_format_width(format);
 320                 int unsignd = snd_pcm_format_unsigned(format) > 0;
 321                 int big = snd_pcm_format_big_endian(format) > 0;
 322                 unsigned int badness, best = -1;
 323                 snd_pcm_format_t best_format = (__force snd_pcm_format_t)-1;
 324                 for (i = 0; i < ARRAY_SIZE(preferred_formats); i++) {
 325                         snd_pcm_format_t f = preferred_formats[i];
 326                         unsigned int w;
 327                         if (!snd_mask_test(format_mask, (__force int)f))
 328                                 continue;
 329                         w = snd_pcm_format_width(f);
 330                         if (w >= width)
 331                                 badness = w - width;
 332                         else
 333                                 badness = width - w + 32;
 334                         badness += snd_pcm_format_unsigned(f) != unsignd;
 335                         badness += snd_pcm_format_big_endian(f) != big;
 336                         if (badness < best) {
 337                                 best_format = f;
 338                                 best = badness;
 339                         }
 340                 }
 341                 if ((__force int)best_format >= 0)
 342                         return best_format;
 343                 else
 344                         return (__force snd_pcm_format_t)-EINVAL;
 345         } else {
 346                 switch (format) {
 347                 case SNDRV_PCM_FORMAT_MU_LAW:
 348                         for (i = 0; i < ARRAY_SIZE(preferred_formats); ++i) {
 349                                 snd_pcm_format_t format1 = preferred_formats[i];
 350                                 if (snd_mask_test(format_mask, (__force int)format1))
 351                                         return format1;
 352                         }
 353                 default:
 354                         return (__force snd_pcm_format_t)-EINVAL;
 355                 }
 356         }
 357 }
 358
 359 int snd_pcm_plug_format_plugins(struct snd_pcm_substream *plug,
 360                                 struct snd_pcm_hw_params *params,
 361                                 struct snd_pcm_hw_params *slave_params)
 362 {
 363         struct snd_pcm_plugin_format tmpformat;
 364         struct snd_pcm_plugin_format dstformat;
 365         struct snd_pcm_plugin_format srcformat;
 366         snd_pcm_access_t src_access, dst_access;
 367         struct snd_pcm_plugin *plugin = NULL;
 368         int err;
 369         int stream = snd_pcm_plug_stream(plug);
 370         int slave_interleaved = (params_channels(slave_params) == 1 ||
 371                                  params_access(slave_params) == SNDRV_PCM_ACCESS_RW_INTERLEAVED);
 372
 373         switch (stream) {
 374         case SNDRV_PCM_STREAM_PLAYBACK:
 375                 dstformat.format = params_format(slave_params);
 376                 dstformat.rate = params_rate(slave_params);
 377                 dstformat.channels = params_channels(slave_params);
 378                 srcformat.format = params_format(params);
 379                 srcformat.rate = params_rate(params);
 380                 srcformat.channels = params_channels(params);
 381                 src_access = SNDRV_PCM_ACCESS_RW_INTERLEAVED;
 382                 dst_access = (slave_interleaved ? SNDRV_PCM_ACCESS_RW_INTERLEAVED :
 383                                                   SNDRV_PCM_ACCESS_RW_NONINTERLEAVED);
 384                 break;
 385         case SNDRV_PCM_STREAM_CAPTURE:
 386                 dstformat.format = params_format(params);
 387                 dstformat.rate = params_rate(params);
 388                 dstformat.channels = params_channels(params);
 389                 srcformat.format = params_format(slave_params);
 390                 srcformat.rate = params_rate(slave_params);
 391                 srcformat.channels = params_channels(slave_params);
 392                 src_access = (slave_interleaved ? SNDRV_PCM_ACCESS_RW_INTERLEAVED :
 393                                                   SNDRV_PCM_ACCESS_RW_NONINTERLEAVED);
 394                 dst_access = SNDRV_PCM_ACCESS_RW_INTERLEAVED;
 395                 break;
 396         default:
 397                 snd_BUG();
 398                 return -EINVAL;
 399         }
 400         tmpformat = srcformat;
 401
 402         pdprintf("srcformat: format=%i, rate=%i, channels=%i\n",
 403                  srcformat.format,
 404                  srcformat.rate,
 405                  srcformat.channels);
 406         pdprintf("dstformat: format=%i, rate=%i, channels=%i\n",
 407                  dstformat.format,
 408                  dstformat.rate,
 409                  dstformat.channels);
 410
 411         /* Format change (linearization) */
 412         if (! rate_match(srcformat.rate, dstformat.rate) &&
 413             ! snd_pcm_format_linear(srcformat.format)) {
 414                 if (srcformat.format != SNDRV_PCM_FORMAT_MU_LAW)
 415                         return -EINVAL;
 416                 tmpformat.format = SNDRV_PCM_FORMAT_S16;
 417                 err = snd_pcm_plugin_build_mulaw(plug,
 418                                                  &srcformat, &tmpformat,
 419                                                  &plugin);
 420                 if (err < 0)
 421                         return err;
 422                 err = snd_pcm_plugin_append(plugin);
 423                 if (err < 0) {
 424                         snd_pcm_plugin_free(plugin);
 425                         return err;
 426                 }
 427                 srcformat = tmpformat;
 428                 src_access = dst_access;
 429         }
 430
 431         /* channels reduction */
 432         if (srcformat.channels > dstformat.channels) {
 433                 tmpformat.channels = dstformat.channels;
 434                 err = snd_pcm_plugin_build_route(plug, &srcformat, &tmpformat, &plugin);
 435                 pdprintf("channels reduction: src=%i, dst=%i returns %i\n", srcformat.channels, tmpformat.channels, err);
 436                 if (err < 0)
 437                         return err;
 438                 err = snd_pcm_plugin_append(plugin);
 439                 if (err < 0) {
 440                         snd_pcm_plugin_free(plugin);
 441                         return err;
 442                 }
 443                 srcformat = tmpformat;
 444                 src_access = dst_access;
 445         }
 446
 447         /* rate resampling */
 448         if (!rate_match(srcformat.rate, dstformat.rate)) {
 449                 if (srcformat.format != SNDRV_PCM_FORMAT_S16) {
 450                         /* convert to S16 for resampling */
 451                         tmpformat.format = SNDRV_PCM_FORMAT_S16;
 452                         err = snd_pcm_plugin_build_linear(plug,
 453                                                           &srcformat, &tmpformat,
 454                                                           &plugin);
 455                         if (err < 0)
 456                                 return err;
 457                         err = snd_pcm_plugin_append(plugin);
 458                         if (err < 0) {
 459                                 snd_pcm_plugin_free(plugin);
 460                                 return err;
 461                         }
 462                         srcformat = tmpformat;
 463                         src_access = dst_access;
 464                 }
 465                 tmpformat.rate = dstformat.rate;
 466                 err = snd_pcm_plugin_build_rate(plug,
 467                                                 &srcformat, &tmpformat,
 468                                                 &plugin);
 469                 pdprintf("rate down resampling: src=%i, dst=%i returns %i\n", srcformat.rate, tmpformat.rate, err);
 470                 if (err < 0)
 471                         return err;
 472                 err = snd_pcm_plugin_append(plugin);
 473                 if (err < 0) {
 474                         snd_pcm_plugin_free(plugin);
 475                         return err;
 476                 }
 477                 srcformat = tmpformat;
 478                 src_access = dst_access;
 479         }
 480
 481         /* format change */
 482         if (srcformat.format != dstformat.format) {
 483                 tmpformat.format = dstformat.format;
 484                 if (srcformat.format == SNDRV_PCM_FORMAT_MU_LAW ||
 485                     tmpformat.format == SNDRV_PCM_FORMAT_MU_LAW) {
 486                         err = snd_pcm_plugin_build_mulaw(plug,
 487                                                          &srcformat, &tmpformat,
 488                                                          &plugin);
 489                 }
 490                 else if (snd_pcm_format_linear(srcformat.format) &&
 491                          snd_pcm_format_linear(tmpformat.format)) {
 492                         err = snd_pcm_plugin_build_linear(plug,
 493                                                           &srcformat, &tmpformat,
 494                                                           &plugin);
 495                 }
 496                 else
 497                         return -EINVAL;
 498                 pdprintf("format change: src=%i, dst=%i returns %i\n", srcformat.format, tmpformat.format, err);
 499                 if (err < 0)
 500                         return err;
 501                 err = snd_pcm_plugin_append(plugin);
 502                 if (err < 0) {
 503                         snd_pcm_plugin_free(plugin);
 504                         return err;
 505                 }
 506                 srcformat = tmpformat;
 507                 src_access = dst_access;
 508         }
 509
 510         /* channels extension */
 511         if (srcformat.channels < dstformat.channels) {
 512                 tmpformat.channels = dstformat.channels;
 513                 err = snd_pcm_plugin_build_route(plug, &srcformat, &tmpformat, &plugin);
 514                 pdprintf("channels extension: src=%i, dst=%i returns %i\n", srcformat.channels, tmpformat.channels, err);
 515                 if (err < 0)
 516                         return err;
 517                 err = snd_pcm_plugin_append(plugin);
 518                 if (err < 0) {
 519                         snd_pcm_plugin_free(plugin);
 520                         return err;
 521                 }
 522                 srcformat = tmpformat;
 523                 src_access = dst_access;
 524         }
 525
 526         /* de-interleave */
 527         if (src_access != dst_access) {
 528                 err = snd_pcm_plugin_build_copy(plug,
 529                                                 &srcformat,
 530                                                 &tmpformat,
 531                                                 &plugin);
 532                 pdprintf("interleave change (copy: returns %i)\n", err);
 533                 if (err < 0)
 534                         return err;
 535                 err = snd_pcm_plugin_append(plugin);
 536                 if (err < 0) {
 537                         snd_pcm_plugin_free(plugin);
 538                         return err;
 539                 }
 540         }
 541
 542         return 0;
 543 }
 544
 545 snd_pcm_sframes_t snd_pcm_plug_client_channels_buf(struct snd_pcm_substream *plug,
 546                                          char *buf,
 547                                          snd_pcm_uframes_t count,
 548                                          struct snd_pcm_plugin_channel **channels)
 549 {
 550         struct snd_pcm_plugin *plugin;
 551         struct snd_pcm_plugin_channel *v;
 552         struct snd_pcm_plugin_format *format;
 553         int width, nchannels, channel;
 554         int stream = snd_pcm_plug_stream(plug);
 555
 556         if (snd_BUG_ON(!buf))
 557                 return -ENXIO;
 558         if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
 559                 plugin = snd_pcm_plug_first(plug);
 560                 format = &plugin->src_format;
 561         } else {
 562                 plugin = snd_pcm_plug_last(plug);
 563                 format = &plugin->dst_format;
 564         }
 565         v = plugin->buf_channels;
 566         *channels = v;
 567         if ((width = snd_pcm_format_physical_width(format->format)) < 0)
 568                 return width;
 569         nchannels = format->channels;
 570         if (snd_BUG_ON(plugin->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
 571                        format->channels > 1))
 572                 return -ENXIO;
 573         for (channel = 0; channel < nchannels; channel++, v++) {
 574                 v->frames = count;
 575                 v->enabled = 1;
 576                 v->wanted = (stream == SNDRV_PCM_STREAM_CAPTURE);
 577                 v->area.addr = buf;
 578                 v->area.first = channel * width;
 579                 v->area.step = nchannels * width;
 580         }
 581         return count;
 582 }
 583
 584 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)
 585 {
 586         struct snd_pcm_plugin *plugin, *next;
 587         struct snd_pcm_plugin_channel *dst_channels;
 588         int err;
 589         snd_pcm_sframes_t frames = size;
 590
 591         plugin = snd_pcm_plug_first(plug);
 592         while (plugin) {
 593                 if (frames <= 0)
 594                         return frames;
 595                 if ((next = plugin->next) != NULL) {
 596                         snd_pcm_sframes_t frames1 = frames;
 597                         if (plugin->dst_frames) {
 598                                 frames1 = plugin->dst_frames(plugin, frames);
 599                                 if (frames1 <= 0)
 600                                         return frames1;
 601                         }
 602                         if ((err = next->client_channels(next, frames1, &dst_channels)) < 0) {
 603                                 return err;
 604                         }
 605                         if (err != frames1) {
 606                                 frames = err;
 607                                 if (plugin->src_frames) {
 608                                         frames = plugin->src_frames(plugin, frames1);
 609                                         if (frames <= 0)
 610                                                 return frames;
 611                                 }
 612                         }
 613                 } else
 614                         dst_channels = NULL;
 615                 pdprintf("write plugin: %s, %li\n", plugin->name, frames);
 616                 if ((frames = plugin->transfer(plugin, src_channels, dst_channels, frames)) < 0)
 617                         return frames;
 618                 src_channels = dst_channels;
 619                 plugin = next;
 620         }
 621         return snd_pcm_plug_client_size(plug, frames);
 622 }
 623
 624 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)
 625 {
 626         struct snd_pcm_plugin *plugin, *next;
 627         struct snd_pcm_plugin_channel *src_channels, *dst_channels;
 628         snd_pcm_sframes_t frames = size;
 629         int err;
 630
 631         frames = snd_pcm_plug_slave_size(plug, frames);
 632         if (frames < 0)
 633                 return frames;
 634
 635         src_channels = NULL;
 636         plugin = snd_pcm_plug_first(plug);
 637         while (plugin && frames > 0) {
 638                 if ((next = plugin->next) != NULL) {
 639                         if ((err = plugin->client_channels(plugin, frames, &dst_channels)) < 0) {
 640                                 return err;
 641                         }
 642                         frames = err;
 643                 } else {
 644                         dst_channels = dst_channels_final;
 645                 }
 646                 pdprintf("read plugin: %s, %li\n", plugin->name, frames);
 647                 if ((frames = plugin->transfer(plugin, src_channels, dst_channels, frames)) < 0)
 648                         return frames;
 649                 plugin = next;
 650                 src_channels = dst_channels;
 651         }
 652         return frames;
 653 }
 654
 655 int snd_pcm_area_silence(const struct snd_pcm_channel_area *dst_area, size_t dst_offset,
 656                          size_t samples, snd_pcm_format_t format)
 657 {
 658         /* FIXME: sub byte resolution and odd dst_offset */
 659         unsigned char *dst;
 660         unsigned int dst_step;
 661         int width;
 662         const unsigned char *silence;
 663         if (!dst_area->addr)
 664                 return 0;
 665         dst = dst_area->addr + (dst_area->first + dst_area->step * dst_offset) / 8;
 666         width = snd_pcm_format_physical_width(format);
 667         if (width <= 0)
 668                 return -EINVAL;
 669         if (dst_area->step == (unsigned int) width && width >= 8)
 670                 return snd_pcm_format_set_silence(format, dst, samples);
 671         silence = snd_pcm_format_silence_64(format);
 672         if (! silence)
 673                 return -EINVAL;
 674         dst_step = dst_area->step / 8;
 675         if (width == 4) {
 676                 /* Ima ADPCM */
 677                 int dstbit = dst_area->first % 8;
 678                 int dstbit_step = dst_area->step % 8;
 679                 while (samples-- > 0) {
 680                         if (dstbit)
 681                                 *dst &= 0xf0;
 682                         else
 683                                 *dst &= 0x0f;
 684                         dst += dst_step;
 685                         dstbit += dstbit_step;
 686                         if (dstbit == 8) {
 687                                 dst++;
 688                                 dstbit = 0;
 689                         }
 690                 }
 691         } else {
 692                 width /= 8;
 693                 while (samples-- > 0) {
 694                         memcpy(dst, silence, width);
 695                         dst += dst_step;
 696                 }
 697         }
 698         return 0;
 699 }
 700
 701 int snd_pcm_area_copy(const struct snd_pcm_channel_area *src_area, size_t src_offset,
 702                       const struct snd_pcm_channel_area *dst_area, size_t dst_offset,
 703                       size_t samples, snd_pcm_format_t format)
 704 {
 705         /* FIXME: sub byte resolution and odd dst_offset */
 706         char *src, *dst;
 707         int width;
 708         int src_step, dst_step;
 709         src = src_area->addr + (src_area->first + src_area->step * src_offset) / 8;
 710         if (!src_area->addr)
 711                 return snd_pcm_area_silence(dst_area, dst_offset, samples, format);
 712         dst = dst_area->addr + (dst_area->first + dst_area->step * dst_offset) / 8;
 713         if (!dst_area->addr)
 714                 return 0;
 715         width = snd_pcm_format_physical_width(format);
 716         if (width <= 0)
 717                 return -EINVAL;
 718         if (src_area->step == (unsigned int) width &&
 719             dst_area->step == (unsigned int) width && width >= 8) {
 720                 size_t bytes = samples * width / 8;
 721                 memcpy(dst, src, bytes);
 722                 return 0;
 723         }
 724         src_step = src_area->step / 8;
 725         dst_step = dst_area->step / 8;
 726         if (width == 4) {
 727                 /* Ima ADPCM */
 728                 int srcbit = src_area->first % 8;
 729                 int srcbit_step = src_area->step % 8;
 730                 int dstbit = dst_area->first % 8;
 731                 int dstbit_step = dst_area->step % 8;
 732                 while (samples-- > 0) {
 733                         unsigned char srcval;
 734                         if (srcbit)
 735                                 srcval = *src & 0x0f;
 736                         else
 737                                 srcval = (*src & 0xf0) >> 4;
 738                         if (dstbit)
 739                                 *dst = (*dst & 0xf0) | srcval;
 740                         else
 741                                 *dst = (*dst & 0x0f) | (srcval << 4);
 742                         src += src_step;
 743                         srcbit += srcbit_step;
 744                         if (srcbit == 8) {
 745                                 src++;
 746                                 srcbit = 0;
 747                         }
 748                         dst += dst_step;
 749                         dstbit += dstbit_step;
 750                         if (dstbit == 8) {
 751                                 dst++;
 752                                 dstbit = 0;
 753                         }
 754                 }
 755         } else {
 756                 width /= 8;
 757                 while (samples-- > 0) {
 758                         memcpy(dst, src, width);
 759                         src += src_step;
 760                         dst += dst_step;
 761                 }
 762         }
 763         return 0;
 764 }