Merge git://git.kernel.org/pub/scm/linux/kernel/git/perex/alsa
[linux-2.6] / 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