sound/core/oss/pcm_plugin.c

   1 /*
   2  *  PCM Plug-In shared (kernel/library) code
   3  *  Copyright (c) 1999 by Jaroslav Kysela <[email protected]>
   4  *  Copyright (c) 2000 by Abramo Bagnara <[email protected]>
   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         width = snd_pcm_format_physical_width(format->format);
  63         if (width < 0)
  64                 return width;
  65         size = array3_size(frames, format->channels, width);
  66         /* check for too large period size once again */
  67         if (size > 1024 * 1024)
  68                 return -ENOMEM;
  69         if (snd_BUG_ON(size % 8))
  70                 return -ENXIO;
  71         size /= 8;
  72         if (plugin->buf_frames < frames) {
  73                 kvfree(plugin->buf);
  74                 plugin->buf = kvzalloc(size, GFP_KERNEL);
  75                 plugin->buf_frames = frames;
  76         }
  77         if (!plugin->buf) {
  78                 plugin->buf_frames = 0;
  79                 return -ENOMEM;
  80         }
  81         c = plugin->buf_channels;
  82         if (plugin->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED) {
  83                 for (channel = 0; channel < format->channels; channel++, c++) {
  84                         c->frames = frames;
  85                         c->enabled = 1;
  86                         c->wanted = 0;
  87                         c->area.addr = plugin->buf;
  88                         c->area.first = channel * width;
  89                         c->area.step = format->channels * width;
  90                 }
  91         } else if (plugin->access == SNDRV_PCM_ACCESS_RW_NONINTERLEAVED) {
  92                 if (snd_BUG_ON(size % format->channels))
  93                         return -EINVAL;
  94                 size /= format->channels;
  95                 for (channel = 0; channel < format->channels; channel++, c++) {
  96                         c->frames = frames;
  97                         c->enabled = 1;
  98                         c->wanted = 0;
  99                         c->area.addr = plugin->buf + (channel * size);
 100                         c->area.first = 0;
 101                         c->area.step = width;
 102                 }
 103         } else
 104                 return -EINVAL;
 105         return 0;
 106 }
 107
 108 int snd_pcm_plug_alloc(struct snd_pcm_substream *plug, snd_pcm_uframes_t frames)
 109 {
 110         int err;
 111         if (snd_BUG_ON(!snd_pcm_plug_first(plug)))
 112                 return -ENXIO;
 113         if (snd_pcm_plug_stream(plug) == SNDRV_PCM_STREAM_PLAYBACK) {
 114                 struct snd_pcm_plugin *plugin = snd_pcm_plug_first(plug);
 115                 while (plugin->next) {
 116                         if (plugin->dst_frames)
 117                                 frames = plugin->dst_frames(plugin, frames);
 118                         if ((snd_pcm_sframes_t)frames <= 0)
 119                                 return -ENXIO;
 120                         plugin = plugin->next;
 121                         err = snd_pcm_plugin_alloc(plugin, frames);
 122                         if (err < 0)
 123                                 return err;
 124                 }
 125         } else {
 126                 struct snd_pcm_plugin *plugin = snd_pcm_plug_last(plug);
 127                 while (plugin->prev) {
 128                         if (plugin->src_frames)
 129                                 frames = plugin->src_frames(plugin, frames);
 130                         if ((snd_pcm_sframes_t)frames <= 0)
 131                                 return -ENXIO;
 132                         plugin = plugin->prev;
 133                         err = snd_pcm_plugin_alloc(plugin, frames);
 134                         if (err < 0)
 135                                 return err;
 136                 }
 137         }
 138         return 0;
 139 }
 140
 141
 142 snd_pcm_sframes_t snd_pcm_plugin_client_channels(struct snd_pcm_plugin *plugin,
 143                                        snd_pcm_uframes_t frames,
 144                                        struct snd_pcm_plugin_channel **channels)
 145 {
 146         *channels = plugin->buf_channels;
 147         return frames;
 148 }
 149
 150 int snd_pcm_plugin_build(struct snd_pcm_substream *plug,
 151                          const char *name,
 152                          struct snd_pcm_plugin_format *src_format,
 153                          struct snd_pcm_plugin_format *dst_format,
 154                          size_t extra,
 155                          struct snd_pcm_plugin **ret)
 156 {
 157         struct snd_pcm_plugin *plugin;
 158         unsigned int channels;
 159
 160         if (snd_BUG_ON(!plug))
 161                 return -ENXIO;
 162         if (snd_BUG_ON(!src_format || !dst_format))
 163                 return -ENXIO;
 164         plugin = kzalloc(sizeof(*plugin) + extra, GFP_KERNEL);
 165         if (plugin == NULL)
 166                 return -ENOMEM;
 167         plugin->name = name;
 168         plugin->plug = plug;
 169         plugin->stream = snd_pcm_plug_stream(plug);
 170         plugin->access = SNDRV_PCM_ACCESS_RW_INTERLEAVED;
 171         plugin->src_format = *src_format;
 172         plugin->src_width = snd_pcm_format_physical_width(src_format->format);
 173         snd_BUG_ON(plugin->src_width <= 0);
 174         plugin->dst_format = *dst_format;
 175         plugin->dst_width = snd_pcm_format_physical_width(dst_format->format);
 176         snd_BUG_ON(plugin->dst_width <= 0);
 177         if (plugin->stream == SNDRV_PCM_STREAM_PLAYBACK)
 178                 channels = src_format->channels;
 179         else
 180                 channels = dst_format->channels;
 181         plugin->buf_channels = kcalloc(channels, sizeof(*plugin->buf_channels), GFP_KERNEL);
 182         if (plugin->buf_channels == NULL) {
 183                 snd_pcm_plugin_free(plugin);
 184                 return -ENOMEM;
 185         }
 186         plugin->client_channels = snd_pcm_plugin_client_channels;
 187         *ret = plugin;
 188         return 0;
 189 }
 190
 191 int snd_pcm_plugin_free(struct snd_pcm_plugin *plugin)
 192 {
 193         if (! plugin)
 194                 return 0;
 195         if (plugin->private_free)
 196                 plugin->private_free(plugin);
 197         kfree(plugin->buf_channels);
 198         kvfree(plugin->buf);
 199         kfree(plugin);
 200         return 0;
 201 }
 202
 203 static snd_pcm_sframes_t calc_dst_frames(struct snd_pcm_substream *plug,
 204                                          snd_pcm_sframes_t frames,
 205                                          bool check_size)
 206 {
 207         struct snd_pcm_plugin *plugin, *plugin_next;
 208
 209         plugin = snd_pcm_plug_first(plug);
 210         while (plugin && frames > 0) {
 211                 plugin_next = plugin->next;
 212                 if (check_size && plugin->buf_frames &&
 213                     frames > plugin->buf_frames)
 214                         frames = plugin->buf_frames;
 215                 if (plugin->dst_frames) {
 216                         frames = plugin->dst_frames(plugin, frames);
 217                         if (frames < 0)
 218                                 return frames;
 219                 }
 220                 plugin = plugin_next;
 221         }
 222         return frames;
 223 }
 224
 225 static snd_pcm_sframes_t calc_src_frames(struct snd_pcm_substream *plug,
 226                                          snd_pcm_sframes_t frames,
 227                                          bool check_size)
 228 {
 229         struct snd_pcm_plugin *plugin, *plugin_prev;
 230
 231         plugin = snd_pcm_plug_last(plug);
 232         while (plugin && frames > 0) {
 233                 plugin_prev = plugin->prev;
 234                 if (plugin->src_frames) {
 235                         frames = plugin->src_frames(plugin, frames);
 236                         if (frames < 0)
 237                                 return frames;
 238                 }
 239                 if (check_size && plugin->buf_frames &&
 240                     frames > plugin->buf_frames)
 241                         frames = plugin->buf_frames;
 242                 plugin = plugin_prev;
 243         }
 244         return frames;
 245 }
 246
 247 snd_pcm_sframes_t snd_pcm_plug_client_size(struct snd_pcm_substream *plug, snd_pcm_uframes_t drv_frames)
 248 {
 249         if (snd_BUG_ON(!plug))
 250                 return -ENXIO;
 251         switch (snd_pcm_plug_stream(plug)) {
 252         case SNDRV_PCM_STREAM_PLAYBACK:
 253                 return calc_src_frames(plug, drv_frames, false);
 254         case SNDRV_PCM_STREAM_CAPTURE:
 255                 return calc_dst_frames(plug, drv_frames, false);
 256         default:
 257                 snd_BUG();
 258                 return -EINVAL;
 259         }
 260 }
 261
 262 snd_pcm_sframes_t snd_pcm_plug_slave_size(struct snd_pcm_substream *plug, snd_pcm_uframes_t clt_frames)
 263 {
 264         if (snd_BUG_ON(!plug))
 265                 return -ENXIO;
 266         switch (snd_pcm_plug_stream(plug)) {
 267         case SNDRV_PCM_STREAM_PLAYBACK:
 268                 return calc_dst_frames(plug, clt_frames, false);
 269         case SNDRV_PCM_STREAM_CAPTURE:
 270                 return calc_src_frames(plug, clt_frames, false);
 271         default:
 272                 snd_BUG();
 273                 return -EINVAL;
 274         }
 275 }
 276
 277 static int snd_pcm_plug_formats(const struct snd_mask *mask,
 278                                 snd_pcm_format_t format)
 279 {
 280         struct snd_mask formats = *mask;
 281         u64 linfmts = (SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S8 |
 282                        SNDRV_PCM_FMTBIT_U16_LE | SNDRV_PCM_FMTBIT_S16_LE |
 283                        SNDRV_PCM_FMTBIT_U16_BE | SNDRV_PCM_FMTBIT_S16_BE |
 284                        SNDRV_PCM_FMTBIT_U24_LE | SNDRV_PCM_FMTBIT_S24_LE |
 285                        SNDRV_PCM_FMTBIT_U24_BE | SNDRV_PCM_FMTBIT_S24_BE |
 286                        SNDRV_PCM_FMTBIT_U24_3LE | SNDRV_PCM_FMTBIT_S24_3LE |
 287                        SNDRV_PCM_FMTBIT_U24_3BE | SNDRV_PCM_FMTBIT_S24_3BE |
 288                        SNDRV_PCM_FMTBIT_U32_LE | SNDRV_PCM_FMTBIT_S32_LE |
 289                        SNDRV_PCM_FMTBIT_U32_BE | SNDRV_PCM_FMTBIT_S32_BE);
 290         snd_mask_set(&formats, (__force int)SNDRV_PCM_FORMAT_MU_LAW);
 291
 292         if (formats.bits[0] & lower_32_bits(linfmts))
 293                 formats.bits[0] |= lower_32_bits(linfmts);
 294         if (formats.bits[1] & upper_32_bits(linfmts))
 295                 formats.bits[1] |= upper_32_bits(linfmts);
 296         return snd_mask_test(&formats, (__force int)format);
 297 }
 298
 299 static const snd_pcm_format_t preferred_formats[] = {
 300         SNDRV_PCM_FORMAT_S16_LE,
 301         SNDRV_PCM_FORMAT_S16_BE,
 302         SNDRV_PCM_FORMAT_U16_LE,
 303         SNDRV_PCM_FORMAT_U16_BE,
 304         SNDRV_PCM_FORMAT_S24_3LE,
 305         SNDRV_PCM_FORMAT_S24_3BE,
 306         SNDRV_PCM_FORMAT_U24_3LE,
 307         SNDRV_PCM_FORMAT_U24_3BE,
 308         SNDRV_PCM_FORMAT_S24_LE,
 309         SNDRV_PCM_FORMAT_S24_BE,
 310         SNDRV_PCM_FORMAT_U24_LE,
 311         SNDRV_PCM_FORMAT_U24_BE,
 312         SNDRV_PCM_FORMAT_S32_LE,
 313         SNDRV_PCM_FORMAT_S32_BE,
 314         SNDRV_PCM_FORMAT_U32_LE,
 315         SNDRV_PCM_FORMAT_U32_BE,
 316         SNDRV_PCM_FORMAT_S8,
 317         SNDRV_PCM_FORMAT_U8
 318 };
 319
 320 snd_pcm_format_t snd_pcm_plug_slave_format(snd_pcm_format_t format,
 321                                            const struct snd_mask *format_mask)
 322 {
 323         int i;
 324
 325         if (snd_mask_test(format_mask, (__force int)format))
 326                 return format;
 327         if (!snd_pcm_plug_formats(format_mask, format))
 328                 return (__force snd_pcm_format_t)-EINVAL;
 329         if (snd_pcm_format_linear(format)) {
 330                 unsigned int width = snd_pcm_format_width(format);
 331                 int unsignd = snd_pcm_format_unsigned(format) > 0;
 332                 int big = snd_pcm_format_big_endian(format) > 0;
 333                 unsigned int badness, best = -1;
 334                 snd_pcm_format_t best_format = (__force snd_pcm_format_t)-1;
 335                 for (i = 0; i < ARRAY_SIZE(preferred_formats); i++) {
 336                         snd_pcm_format_t f = preferred_formats[i];
 337                         unsigned int w;
 338                         if (!snd_mask_test(format_mask, (__force int)f))
 339                                 continue;
 340                         w = snd_pcm_format_width(f);
 341                         if (w >= width)
 342                                 badness = w - width;
 343                         else
 344                                 badness = width - w + 32;
 345                         badness += snd_pcm_format_unsigned(f) != unsignd;
 346                         badness += snd_pcm_format_big_endian(f) != big;
 347                         if (badness < best) {
 348                                 best_format = f;
 349                                 best = badness;
 350                         }
 351                 }
 352                 if ((__force int)best_format >= 0)
 353                         return best_format;
 354                 else
 355                         return (__force snd_pcm_format_t)-EINVAL;
 356         } else {
 357                 switch (format) {
 358                 case SNDRV_PCM_FORMAT_MU_LAW:
 359                         for (i = 0; i < ARRAY_SIZE(preferred_formats); ++i) {
 360                                 snd_pcm_format_t format1 = preferred_formats[i];
 361                                 if (snd_mask_test(format_mask, (__force int)format1))
 362                                         return format1;
 363                         }
 364                         fallthrough;
 365                 default:
 366                         return (__force snd_pcm_format_t)-EINVAL;
 367                 }
 368         }
 369 }
 370
 371 int snd_pcm_plug_format_plugins(struct snd_pcm_substream *plug,
 372                                 struct snd_pcm_hw_params *params,
 373                                 struct snd_pcm_hw_params *slave_params)
 374 {
 375         struct snd_pcm_plugin_format tmpformat;
 376         struct snd_pcm_plugin_format dstformat;
 377         struct snd_pcm_plugin_format srcformat;
 378         snd_pcm_access_t src_access, dst_access;
 379         struct snd_pcm_plugin *plugin = NULL;
 380         int err;
 381         int stream = snd_pcm_plug_stream(plug);
 382         int slave_interleaved = (params_channels(slave_params) == 1 ||
 383                                  params_access(slave_params) == SNDRV_PCM_ACCESS_RW_INTERLEAVED);
 384
 385         switch (stream) {
 386         case SNDRV_PCM_STREAM_PLAYBACK:
 387                 dstformat.format = params_format(slave_params);
 388                 dstformat.rate = params_rate(slave_params);
 389                 dstformat.channels = params_channels(slave_params);
 390                 srcformat.format = params_format(params);
 391                 srcformat.rate = params_rate(params);
 392                 srcformat.channels = params_channels(params);
 393                 src_access = SNDRV_PCM_ACCESS_RW_INTERLEAVED;
 394                 dst_access = (slave_interleaved ? SNDRV_PCM_ACCESS_RW_INTERLEAVED :
 395                                                   SNDRV_PCM_ACCESS_RW_NONINTERLEAVED);
 396                 break;
 397         case SNDRV_PCM_STREAM_CAPTURE:
 398                 dstformat.format = params_format(params);
 399                 dstformat.rate = params_rate(params);
 400                 dstformat.channels = params_channels(params);
 401                 srcformat.format = params_format(slave_params);
 402                 srcformat.rate = params_rate(slave_params);
 403                 srcformat.channels = params_channels(slave_params);
 404                 src_access = (slave_interleaved ? SNDRV_PCM_ACCESS_RW_INTERLEAVED :
 405                                                   SNDRV_PCM_ACCESS_RW_NONINTERLEAVED);
 406                 dst_access = SNDRV_PCM_ACCESS_RW_INTERLEAVED;
 407                 break;
 408         default:
 409                 snd_BUG();
 410                 return -EINVAL;
 411         }
 412         tmpformat = srcformat;
 413
 414         pdprintf("srcformat: format=%i, rate=%i, channels=%i\n",
 415                  srcformat.format,
 416                  srcformat.rate,
 417                  srcformat.channels);
 418         pdprintf("dstformat: format=%i, rate=%i, channels=%i\n",
 419                  dstformat.format,
 420                  dstformat.rate,
 421                  dstformat.channels);
 422
 423         /* Format change (linearization) */
 424         if (! rate_match(srcformat.rate, dstformat.rate) &&
 425             ! snd_pcm_format_linear(srcformat.format)) {
 426                 if (srcformat.format != SNDRV_PCM_FORMAT_MU_LAW)
 427                         return -EINVAL;
 428                 tmpformat.format = SNDRV_PCM_FORMAT_S16;
 429                 err = snd_pcm_plugin_build_mulaw(plug,
 430                                                  &srcformat, &tmpformat,
 431                                                  &plugin);
 432                 if (err < 0)
 433                         return err;
 434                 err = snd_pcm_plugin_append(plugin);
 435                 if (err < 0) {
 436                         snd_pcm_plugin_free(plugin);
 437                         return err;
 438                 }
 439                 srcformat = tmpformat;
 440                 src_access = dst_access;
 441         }
 442
 443         /* channels reduction */
 444         if (srcformat.channels > dstformat.channels) {
 445                 tmpformat.channels = dstformat.channels;
 446                 err = snd_pcm_plugin_build_route(plug, &srcformat, &tmpformat, &plugin);
 447                 pdprintf("channels reduction: src=%i, dst=%i returns %i\n", srcformat.channels, tmpformat.channels, err);
 448                 if (err < 0)
 449                         return err;
 450                 err = snd_pcm_plugin_append(plugin);
 451                 if (err < 0) {
 452                         snd_pcm_plugin_free(plugin);
 453                         return err;
 454                 }
 455                 srcformat = tmpformat;
 456                 src_access = dst_access;
 457         }
 458
 459         /* rate resampling */
 460         if (!rate_match(srcformat.rate, dstformat.rate)) {
 461                 if (srcformat.format != SNDRV_PCM_FORMAT_S16) {
 462                         /* convert to S16 for resampling */
 463                         tmpformat.format = SNDRV_PCM_FORMAT_S16;
 464                         err = snd_pcm_plugin_build_linear(plug,
 465                                                           &srcformat, &tmpformat,
 466                                                           &plugin);
 467                         if (err < 0)
 468                                 return err;
 469                         err = snd_pcm_plugin_append(plugin);
 470                         if (err < 0) {
 471                                 snd_pcm_plugin_free(plugin);
 472                                 return err;
 473                         }
 474                         srcformat = tmpformat;
 475                         src_access = dst_access;
 476                 }
 477                 tmpformat.rate = dstformat.rate;
 478                 err = snd_pcm_plugin_build_rate(plug,
 479                                                 &srcformat, &tmpformat,
 480                                                 &plugin);
 481                 pdprintf("rate down resampling: src=%i, dst=%i returns %i\n", srcformat.rate, tmpformat.rate, err);
 482                 if (err < 0)
 483                         return err;
 484                 err = snd_pcm_plugin_append(plugin);
 485                 if (err < 0) {
 486                         snd_pcm_plugin_free(plugin);
 487                         return err;
 488                 }
 489                 srcformat = tmpformat;
 490                 src_access = dst_access;
 491         }
 492
 493         /* format change */
 494         if (srcformat.format != dstformat.format) {
 495                 tmpformat.format = dstformat.format;
 496                 if (srcformat.format == SNDRV_PCM_FORMAT_MU_LAW ||
 497                     tmpformat.format == SNDRV_PCM_FORMAT_MU_LAW) {
 498                         err = snd_pcm_plugin_build_mulaw(plug,
 499                                                          &srcformat, &tmpformat,
 500                                                          &plugin);
 501                 }
 502                 else if (snd_pcm_format_linear(srcformat.format) &&
 503                          snd_pcm_format_linear(tmpformat.format)) {
 504                         err = snd_pcm_plugin_build_linear(plug,
 505                                                           &srcformat, &tmpformat,
 506                                                           &plugin);
 507                 }
 508                 else
 509                         return -EINVAL;
 510                 pdprintf("format change: src=%i, dst=%i returns %i\n", srcformat.format, tmpformat.format, err);
 511                 if (err < 0)
 512                         return err;
 513                 err = snd_pcm_plugin_append(plugin);
 514                 if (err < 0) {
 515                         snd_pcm_plugin_free(plugin);
 516                         return err;
 517                 }
 518                 srcformat = tmpformat;
 519                 src_access = dst_access;
 520         }
 521
 522         /* channels extension */
 523         if (srcformat.channels < dstformat.channels) {
 524                 tmpformat.channels = dstformat.channels;
 525                 err = snd_pcm_plugin_build_route(plug, &srcformat, &tmpformat, &plugin);
 526                 pdprintf("channels extension: src=%i, dst=%i returns %i\n", srcformat.channels, tmpformat.channels, err);
 527                 if (err < 0)
 528                         return err;
 529                 err = snd_pcm_plugin_append(plugin);
 530                 if (err < 0) {
 531                         snd_pcm_plugin_free(plugin);
 532                         return err;
 533                 }
 534                 srcformat = tmpformat;
 535                 src_access = dst_access;
 536         }
 537
 538         /* de-interleave */
 539         if (src_access != dst_access) {
 540                 err = snd_pcm_plugin_build_copy(plug,
 541                                                 &srcformat,
 542                                                 &tmpformat,
 543                                                 &plugin);
 544                 pdprintf("interleave change (copy: returns %i)\n", err);
 545                 if (err < 0)
 546                         return err;
 547                 err = snd_pcm_plugin_append(plugin);
 548                 if (err < 0) {
 549                         snd_pcm_plugin_free(plugin);
 550                         return err;
 551                 }
 552         }
 553
 554         return 0;
 555 }
 556
 557 snd_pcm_sframes_t snd_pcm_plug_client_channels_buf(struct snd_pcm_substream *plug,
 558                                          char *buf,
 559                                          snd_pcm_uframes_t count,
 560                                          struct snd_pcm_plugin_channel **channels)
 561 {
 562         struct snd_pcm_plugin *plugin;
 563         struct snd_pcm_plugin_channel *v;
 564         struct snd_pcm_plugin_format *format;
 565         int width, nchannels, channel;
 566         int stream = snd_pcm_plug_stream(plug);
 567
 568         if (snd_BUG_ON(!buf))
 569                 return -ENXIO;
 570         if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
 571                 plugin = snd_pcm_plug_first(plug);
 572                 format = &plugin->src_format;
 573         } else {
 574                 plugin = snd_pcm_plug_last(plug);
 575                 format = &plugin->dst_format;
 576         }
 577         v = plugin->buf_channels;
 578         *channels = v;
 579         width = snd_pcm_format_physical_width(format->format);
 580         if (width < 0)
 581                 return width;
 582         nchannels = format->channels;
 583         if (snd_BUG_ON(plugin->access != SNDRV_PCM_ACCESS_RW_INTERLEAVED &&
 584                        format->channels > 1))
 585                 return -ENXIO;
 586         for (channel = 0; channel < nchannels; channel++, v++) {
 587                 v->frames = count;
 588                 v->enabled = 1;
 589                 v->wanted = (stream == SNDRV_PCM_STREAM_CAPTURE);
 590                 v->area.addr = buf;
 591                 v->area.first = channel * width;
 592                 v->area.step = nchannels * width;
 593         }
 594         return count;
 595 }
 596
 597 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)
 598 {
 599         struct snd_pcm_plugin *plugin, *next;
 600         struct snd_pcm_plugin_channel *dst_channels;
 601         int err;
 602         snd_pcm_sframes_t frames = size;
 603
 604         plugin = snd_pcm_plug_first(plug);
 605         while (plugin) {
 606                 if (frames <= 0)
 607                         return frames;
 608                 next = plugin->next;
 609                 if (next) {
 610                         snd_pcm_sframes_t frames1 = frames;
 611                         if (plugin->dst_frames) {
 612                                 frames1 = plugin->dst_frames(plugin, frames);
 613                                 if (frames1 <= 0)
 614                                         return frames1;
 615                         }
 616                         err = next->client_channels(next, frames1, &dst_channels);
 617                         if (err < 0)
 618                                 return err;
 619                         if (err != frames1) {
 620                                 frames = err;
 621                                 if (plugin->src_frames) {
 622                                         frames = plugin->src_frames(plugin, frames1);
 623                                         if (frames <= 0)
 624                                                 return frames;
 625                                 }
 626                         }
 627                 } else
 628                         dst_channels = NULL;
 629                 pdprintf("write plugin: %s, %li\n", plugin->name, frames);
 630                 frames = plugin->transfer(plugin, src_channels, dst_channels, frames);
 631                 if (frames < 0)
 632                         return frames;
 633                 src_channels = dst_channels;
 634                 plugin = next;
 635         }
 636         return calc_src_frames(plug, frames, true);
 637 }
 638
 639 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)
 640 {
 641         struct snd_pcm_plugin *plugin, *next;
 642         struct snd_pcm_plugin_channel *src_channels, *dst_channels;
 643         snd_pcm_sframes_t frames = size;
 644         int err;
 645
 646         frames = calc_src_frames(plug, frames, true);
 647         if (frames < 0)
 648                 return frames;
 649
 650         src_channels = NULL;
 651         plugin = snd_pcm_plug_first(plug);
 652         while (plugin && frames > 0) {
 653                 next = plugin->next;
 654                 if (next) {
 655                         err = plugin->client_channels(plugin, frames, &dst_channels);
 656                         if (err < 0)
 657                                 return err;
 658                         frames = err;
 659                 } else {
 660                         dst_channels = dst_channels_final;
 661                 }
 662                 pdprintf("read plugin: %s, %li\n", plugin->name, frames);
 663                 frames = plugin->transfer(plugin, src_channels, dst_channels, frames);
 664                 if (frames < 0)
 665                         return frames;
 666                 plugin = next;
 667                 src_channels = dst_channels;
 668         }
 669         return frames;
 670 }
 671
 672 int snd_pcm_area_silence(const struct snd_pcm_channel_area *dst_area, size_t dst_offset,
 673                          size_t samples, snd_pcm_format_t format)
 674 {
 675         /* FIXME: sub byte resolution and odd dst_offset */
 676         unsigned char *dst;
 677         unsigned int dst_step;
 678         int width;
 679         const unsigned char *silence;
 680         if (!dst_area->addr)
 681                 return 0;
 682         dst = dst_area->addr + (dst_area->first + dst_area->step * dst_offset) / 8;
 683         width = snd_pcm_format_physical_width(format);
 684         if (width <= 0)
 685                 return -EINVAL;
 686         if (dst_area->step == (unsigned int) width && width >= 8)
 687                 return snd_pcm_format_set_silence(format, dst, samples);
 688         silence = snd_pcm_format_silence_64(format);
 689         if (! silence)
 690                 return -EINVAL;
 691         dst_step = dst_area->step / 8;
 692         if (width == 4) {
 693                 /* Ima ADPCM */
 694                 int dstbit = dst_area->first % 8;
 695                 int dstbit_step = dst_area->step % 8;
 696                 while (samples-- > 0) {
 697                         if (dstbit)
 698                                 *dst &= 0xf0;
 699                         else
 700                                 *dst &= 0x0f;
 701                         dst += dst_step;
 702                         dstbit += dstbit_step;
 703                         if (dstbit == 8) {
 704                                 dst++;
 705                                 dstbit = 0;
 706                         }
 707                 }
 708         } else {
 709                 width /= 8;
 710                 while (samples-- > 0) {
 711                         memcpy(dst, silence, width);
 712                         dst += dst_step;
 713                 }
 714         }
 715         return 0;
 716 }
 717
 718 int snd_pcm_area_copy(const struct snd_pcm_channel_area *src_area, size_t src_offset,
 719                       const struct snd_pcm_channel_area *dst_area, size_t dst_offset,
 720                       size_t samples, snd_pcm_format_t format)
 721 {
 722         /* FIXME: sub byte resolution and odd dst_offset */
 723         char *src, *dst;
 724         int width;
 725         int src_step, dst_step;
 726         src = src_area->addr + (src_area->first + src_area->step * src_offset) / 8;
 727         if (!src_area->addr)
 728                 return snd_pcm_area_silence(dst_area, dst_offset, samples, format);
 729         dst = dst_area->addr + (dst_area->first + dst_area->step * dst_offset) / 8;
 730         if (!dst_area->addr)
 731                 return 0;
 732         width = snd_pcm_format_physical_width(format);
 733         if (width <= 0)
 734                 return -EINVAL;
 735         if (src_area->step == (unsigned int) width &&
 736             dst_area->step == (unsigned int) width && width >= 8) {
 737                 size_t bytes = samples * width / 8;
 738                 memcpy(dst, src, bytes);
 739                 return 0;
 740         }
 741         src_step = src_area->step / 8;
 742         dst_step = dst_area->step / 8;
 743         if (width == 4) {
 744                 /* Ima ADPCM */
 745                 int srcbit = src_area->first % 8;
 746                 int srcbit_step = src_area->step % 8;
 747                 int dstbit = dst_area->first % 8;
 748                 int dstbit_step = dst_area->step % 8;
 749                 while (samples-- > 0) {
 750                         unsigned char srcval;
 751                         if (srcbit)
 752                                 srcval = *src & 0x0f;
 753                         else
 754                                 srcval = (*src & 0xf0) >> 4;
 755                         if (dstbit)
 756                                 *dst = (*dst & 0xf0) | srcval;
 757                         else
 758                                 *dst = (*dst & 0x0f) | (srcval << 4);
 759                         src += src_step;
 760                         srcbit += srcbit_step;
 761                         if (srcbit == 8) {
 762                                 src++;
 763                                 srcbit = 0;
 764                         }
 765                         dst += dst_step;
 766                         dstbit += dstbit_step;
 767                         if (dstbit == 8) {
 768                                 dst++;
 769                                 dstbit = 0;
 770                         }
 771                 }
 772         } else {
 773                 width /= 8;
 774                 while (samples-- > 0) {
 775                         memcpy(dst, src, width);
 776                         src += src_step;
 777                         dst += dst_step;
 778                 }
 779         }
 780         return 0;
 781 }