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pcm_plugin.c
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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  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 && frames > 0) {
593  if ((next = plugin->next) != NULL) {
594  snd_pcm_sframes_t frames1 = frames;
595  if (plugin->dst_frames)
596  frames1 = plugin->dst_frames(plugin, frames);
597  if ((err = next->client_channels(next, frames1, &dst_channels)) < 0) {
598  return err;
599  }
600  if (err != frames1) {
601  frames = err;
602  if (plugin->src_frames)
603  frames = plugin->src_frames(plugin, frames1);
604  }
605  } else
606  dst_channels = NULL;
607  pdprintf("write plugin: %s, %li\n", plugin->name, frames);
608  if ((frames = plugin->transfer(plugin, src_channels, dst_channels, frames)) < 0)
609  return frames;
610  src_channels = dst_channels;
611  plugin = next;
612  }
613  return snd_pcm_plug_client_size(plug, frames);
614 }
615 
616 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)
617 {
618  struct snd_pcm_plugin *plugin, *next;
619  struct snd_pcm_plugin_channel *src_channels, *dst_channels;
620  snd_pcm_sframes_t frames = size;
621  int err;
622 
623  frames = snd_pcm_plug_slave_size(plug, frames);
624  if (frames < 0)
625  return frames;
626 
627  src_channels = NULL;
628  plugin = snd_pcm_plug_first(plug);
629  while (plugin && frames > 0) {
630  if ((next = plugin->next) != NULL) {
631  if ((err = plugin->client_channels(plugin, frames, &dst_channels)) < 0) {
632  return err;
633  }
634  frames = err;
635  } else {
636  dst_channels = dst_channels_final;
637  }
638  pdprintf("read plugin: %s, %li\n", plugin->name, frames);
639  if ((frames = plugin->transfer(plugin, src_channels, dst_channels, frames)) < 0)
640  return frames;
641  plugin = next;
642  src_channels = dst_channels;
643  }
644  return frames;
645 }
646 
647 int snd_pcm_area_silence(const struct snd_pcm_channel_area *dst_area, size_t dst_offset,
648  size_t samples, snd_pcm_format_t format)
649 {
650  /* FIXME: sub byte resolution and odd dst_offset */
651  unsigned char *dst;
652  unsigned int dst_step;
653  int width;
654  const unsigned char *silence;
655  if (!dst_area->addr)
656  return 0;
657  dst = dst_area->addr + (dst_area->first + dst_area->step * dst_offset) / 8;
658  width = snd_pcm_format_physical_width(format);
659  if (width <= 0)
660  return -EINVAL;
661  if (dst_area->step == (unsigned int) width && width >= 8)
662  return snd_pcm_format_set_silence(format, dst, samples);
663  silence = snd_pcm_format_silence_64(format);
664  if (! silence)
665  return -EINVAL;
666  dst_step = dst_area->step / 8;
667  if (width == 4) {
668  /* Ima ADPCM */
669  int dstbit = dst_area->first % 8;
670  int dstbit_step = dst_area->step % 8;
671  while (samples-- > 0) {
672  if (dstbit)
673  *dst &= 0xf0;
674  else
675  *dst &= 0x0f;
676  dst += dst_step;
677  dstbit += dstbit_step;
678  if (dstbit == 8) {
679  dst++;
680  dstbit = 0;
681  }
682  }
683  } else {
684  width /= 8;
685  while (samples-- > 0) {
686  memcpy(dst, silence, width);
687  dst += dst_step;
688  }
689  }
690  return 0;
691 }
692 
693 int snd_pcm_area_copy(const struct snd_pcm_channel_area *src_area, size_t src_offset,
694  const struct snd_pcm_channel_area *dst_area, size_t dst_offset,
695  size_t samples, snd_pcm_format_t format)
696 {
697  /* FIXME: sub byte resolution and odd dst_offset */
698  char *src, *dst;
699  int width;
700  int src_step, dst_step;
701  src = src_area->addr + (src_area->first + src_area->step * src_offset) / 8;
702  if (!src_area->addr)
703  return snd_pcm_area_silence(dst_area, dst_offset, samples, format);
704  dst = dst_area->addr + (dst_area->first + dst_area->step * dst_offset) / 8;
705  if (!dst_area->addr)
706  return 0;
707  width = snd_pcm_format_physical_width(format);
708  if (width <= 0)
709  return -EINVAL;
710  if (src_area->step == (unsigned int) width &&
711  dst_area->step == (unsigned int) width && width >= 8) {
712  size_t bytes = samples * width / 8;
713  memcpy(dst, src, bytes);
714  return 0;
715  }
716  src_step = src_area->step / 8;
717  dst_step = dst_area->step / 8;
718  if (width == 4) {
719  /* Ima ADPCM */
720  int srcbit = src_area->first % 8;
721  int srcbit_step = src_area->step % 8;
722  int dstbit = dst_area->first % 8;
723  int dstbit_step = dst_area->step % 8;
724  while (samples-- > 0) {
725  unsigned char srcval;
726  if (srcbit)
727  srcval = *src & 0x0f;
728  else
729  srcval = (*src & 0xf0) >> 4;
730  if (dstbit)
731  *dst = (*dst & 0xf0) | srcval;
732  else
733  *dst = (*dst & 0x0f) | (srcval << 4);
734  src += src_step;
735  srcbit += srcbit_step;
736  if (srcbit == 8) {
737  src++;
738  srcbit = 0;
739  }
740  dst += dst_step;
741  dstbit += dstbit_step;
742  if (dstbit == 8) {
743  dst++;
744  dstbit = 0;
745  }
746  }
747  } else {
748  width /= 8;
749  while (samples-- > 0) {
750  memcpy(dst, src, width);
751  src += src_step;
752  dst += dst_step;
753  }
754  }
755  return 0;
756 }
Generated on Thu Jan 10 2013 15:03:47 for Linux Kernel by   doxygen 1.8.2