2 * PCM Plug-In shared (kernel/library) code
3 * Copyright (c) 1999 by Jaroslav Kysela <perex@perex.cz>
4 * Copyright (c) 2000 by Abramo Bagnara <abramo@alsa-project.org>
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.
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.
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
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"
35 #define snd_pcm_plug_first(plug) ((plug)->runtime->oss.plugin_first)
36 #define snd_pcm_plug_last(plug) ((plug)->runtime->oss.plugin_last)
39 * because some cards might have rates "very close", we ignore
40 * all "resampling" requests within +-5%
42 static int rate_match(unsigned int src_rate
, unsigned int dst_rate
)
44 unsigned int low
= (src_rate
* 95) / 100;
45 unsigned int high
= (src_rate
* 105) / 100;
46 return dst_rate
>= low
&& dst_rate
<= high
;
49 static int snd_pcm_plugin_alloc(struct snd_pcm_plugin
*plugin
, snd_pcm_uframes_t frames
)
51 struct snd_pcm_plugin_format
*format
;
55 struct snd_pcm_plugin_channel
*c
;
57 if (plugin
->stream
== SNDRV_PCM_STREAM_PLAYBACK
) {
58 format
= &plugin
->src_format
;
60 format
= &plugin
->dst_format
;
62 if ((width
= snd_pcm_format_physical_width(format
->format
)) < 0)
64 size
= frames
* format
->channels
* width
;
65 if (snd_BUG_ON(size
% 8))
68 if (plugin
->buf_frames
< frames
) {
70 plugin
->buf
= vmalloc(size
);
71 plugin
->buf_frames
= frames
;
74 plugin
->buf_frames
= 0;
77 c
= plugin
->buf_channels
;
78 if (plugin
->access
== SNDRV_PCM_ACCESS_RW_INTERLEAVED
) {
79 for (channel
= 0; channel
< format
->channels
; channel
++, c
++) {
83 c
->area
.addr
= plugin
->buf
;
84 c
->area
.first
= channel
* width
;
85 c
->area
.step
= format
->channels
* width
;
87 } else if (plugin
->access
== SNDRV_PCM_ACCESS_RW_NONINTERLEAVED
) {
88 if (snd_BUG_ON(size
% format
->channels
))
90 size
/= format
->channels
;
91 for (channel
= 0; channel
< format
->channels
; channel
++, c
++) {
95 c
->area
.addr
= plugin
->buf
+ (channel
* size
);
104 int snd_pcm_plug_alloc(struct snd_pcm_substream
*plug
, snd_pcm_uframes_t frames
)
107 if (snd_BUG_ON(!snd_pcm_plug_first(plug
)))
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_pcm_sframes_t
)frames
<= 0)
116 plugin
= plugin
->next
;
117 err
= snd_pcm_plugin_alloc(plugin
, frames
);
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_pcm_sframes_t
)frames
<= 0)
128 plugin
= plugin
->prev
;
129 err
= snd_pcm_plugin_alloc(plugin
, frames
);
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
)
142 *channels
= plugin
->buf_channels
;
146 int snd_pcm_plugin_build(struct snd_pcm_substream
*plug
,
148 struct snd_pcm_plugin_format
*src_format
,
149 struct snd_pcm_plugin_format
*dst_format
,
151 struct snd_pcm_plugin
**ret
)
153 struct snd_pcm_plugin
*plugin
;
154 unsigned int channels
;
156 if (snd_BUG_ON(!plug
))
158 if (snd_BUG_ON(!src_format
|| !dst_format
))
160 plugin
= kzalloc(sizeof(*plugin
) + extra
, GFP_KERNEL
);
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
;
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
);
182 plugin
->client_channels
= snd_pcm_plugin_client_channels
;
187 int snd_pcm_plugin_free(struct snd_pcm_plugin
*plugin
)
191 if (plugin
->private_free
)
192 plugin
->private_free(plugin
);
193 kfree(plugin
->buf_channels
);
199 static snd_pcm_sframes_t
plug_client_size(struct snd_pcm_substream
*plug
,
200 snd_pcm_uframes_t drv_frames
,
203 struct snd_pcm_plugin
*plugin
, *plugin_prev
, *plugin_next
;
206 if (snd_BUG_ON(!plug
))
210 stream
= snd_pcm_plug_stream(plug
);
211 if (stream
== SNDRV_PCM_STREAM_PLAYBACK
) {
212 plugin
= snd_pcm_plug_last(plug
);
213 while (plugin
&& drv_frames
> 0) {
214 plugin_prev
= plugin
->prev
;
215 if (plugin
->src_frames
)
216 drv_frames
= plugin
->src_frames(plugin
, drv_frames
);
217 if (check_size
&& plugin
->buf_frames
&&
218 drv_frames
> plugin
->buf_frames
)
219 drv_frames
= plugin
->buf_frames
;
220 plugin
= plugin_prev
;
222 } else if (stream
== SNDRV_PCM_STREAM_CAPTURE
) {
223 plugin
= snd_pcm_plug_first(plug
);
224 while (plugin
&& drv_frames
> 0) {
225 plugin_next
= plugin
->next
;
226 if (check_size
&& plugin
->buf_frames
&&
227 drv_frames
> plugin
->buf_frames
)
228 drv_frames
= plugin
->buf_frames
;
229 if (plugin
->dst_frames
)
230 drv_frames
= plugin
->dst_frames(plugin
, drv_frames
);
231 plugin
= plugin_next
;
238 static snd_pcm_sframes_t
plug_slave_size(struct snd_pcm_substream
*plug
,
239 snd_pcm_uframes_t clt_frames
,
242 struct snd_pcm_plugin
*plugin
, *plugin_prev
, *plugin_next
;
243 snd_pcm_sframes_t frames
;
246 if (snd_BUG_ON(!plug
))
251 stream
= snd_pcm_plug_stream(plug
);
252 if (stream
== SNDRV_PCM_STREAM_PLAYBACK
) {
253 plugin
= snd_pcm_plug_first(plug
);
254 while (plugin
&& frames
> 0) {
255 plugin_next
= plugin
->next
;
256 if (check_size
&& plugin
->buf_frames
&&
257 frames
> plugin
->buf_frames
)
258 frames
= plugin
->buf_frames
;
259 if (plugin
->dst_frames
) {
260 frames
= plugin
->dst_frames(plugin
, frames
);
264 plugin
= plugin_next
;
266 } else if (stream
== SNDRV_PCM_STREAM_CAPTURE
) {
267 plugin
= snd_pcm_plug_last(plug
);
269 plugin_prev
= plugin
->prev
;
270 if (plugin
->src_frames
) {
271 frames
= plugin
->src_frames(plugin
, frames
);
275 if (check_size
&& plugin
->buf_frames
&&
276 frames
> plugin
->buf_frames
)
277 frames
= plugin
->buf_frames
;
278 plugin
= plugin_prev
;
285 snd_pcm_sframes_t
snd_pcm_plug_client_size(struct snd_pcm_substream
*plug
,
286 snd_pcm_uframes_t drv_frames
)
288 return plug_client_size(plug
, drv_frames
, false);
291 snd_pcm_sframes_t
snd_pcm_plug_slave_size(struct snd_pcm_substream
*plug
,
292 snd_pcm_uframes_t clt_frames
)
294 return plug_slave_size(plug
, clt_frames
, false);
297 static int snd_pcm_plug_formats(struct snd_mask
*mask
, snd_pcm_format_t format
)
299 struct snd_mask formats
= *mask
;
300 u64 linfmts
= (SNDRV_PCM_FMTBIT_U8
| SNDRV_PCM_FMTBIT_S8
|
301 SNDRV_PCM_FMTBIT_U16_LE
| SNDRV_PCM_FMTBIT_S16_LE
|
302 SNDRV_PCM_FMTBIT_U16_BE
| SNDRV_PCM_FMTBIT_S16_BE
|
303 SNDRV_PCM_FMTBIT_U24_LE
| SNDRV_PCM_FMTBIT_S24_LE
|
304 SNDRV_PCM_FMTBIT_U24_BE
| SNDRV_PCM_FMTBIT_S24_BE
|
305 SNDRV_PCM_FMTBIT_U24_3LE
| SNDRV_PCM_FMTBIT_S24_3LE
|
306 SNDRV_PCM_FMTBIT_U24_3BE
| SNDRV_PCM_FMTBIT_S24_3BE
|
307 SNDRV_PCM_FMTBIT_U32_LE
| SNDRV_PCM_FMTBIT_S32_LE
|
308 SNDRV_PCM_FMTBIT_U32_BE
| SNDRV_PCM_FMTBIT_S32_BE
);
309 snd_mask_set(&formats
, (__force
int)SNDRV_PCM_FORMAT_MU_LAW
);
311 if (formats
.bits
[0] & (u32
)linfmts
)
312 formats
.bits
[0] |= (u32
)linfmts
;
313 if (formats
.bits
[1] & (u32
)(linfmts
>> 32))
314 formats
.bits
[1] |= (u32
)(linfmts
>> 32);
315 return snd_mask_test(&formats
, (__force
int)format
);
318 static snd_pcm_format_t preferred_formats
[] = {
319 SNDRV_PCM_FORMAT_S16_LE
,
320 SNDRV_PCM_FORMAT_S16_BE
,
321 SNDRV_PCM_FORMAT_U16_LE
,
322 SNDRV_PCM_FORMAT_U16_BE
,
323 SNDRV_PCM_FORMAT_S24_3LE
,
324 SNDRV_PCM_FORMAT_S24_3BE
,
325 SNDRV_PCM_FORMAT_U24_3LE
,
326 SNDRV_PCM_FORMAT_U24_3BE
,
327 SNDRV_PCM_FORMAT_S24_LE
,
328 SNDRV_PCM_FORMAT_S24_BE
,
329 SNDRV_PCM_FORMAT_U24_LE
,
330 SNDRV_PCM_FORMAT_U24_BE
,
331 SNDRV_PCM_FORMAT_S32_LE
,
332 SNDRV_PCM_FORMAT_S32_BE
,
333 SNDRV_PCM_FORMAT_U32_LE
,
334 SNDRV_PCM_FORMAT_U32_BE
,
339 snd_pcm_format_t
snd_pcm_plug_slave_format(snd_pcm_format_t format
,
340 struct snd_mask
*format_mask
)
344 if (snd_mask_test(format_mask
, (__force
int)format
))
346 if (!snd_pcm_plug_formats(format_mask
, format
))
347 return (__force snd_pcm_format_t
)-EINVAL
;
348 if (snd_pcm_format_linear(format
)) {
349 unsigned int width
= snd_pcm_format_width(format
);
350 int unsignd
= snd_pcm_format_unsigned(format
) > 0;
351 int big
= snd_pcm_format_big_endian(format
) > 0;
352 unsigned int badness
, best
= -1;
353 snd_pcm_format_t best_format
= (__force snd_pcm_format_t
)-1;
354 for (i
= 0; i
< ARRAY_SIZE(preferred_formats
); i
++) {
355 snd_pcm_format_t f
= preferred_formats
[i
];
357 if (!snd_mask_test(format_mask
, (__force
int)f
))
359 w
= snd_pcm_format_width(f
);
363 badness
= width
- w
+ 32;
364 badness
+= snd_pcm_format_unsigned(f
) != unsignd
;
365 badness
+= snd_pcm_format_big_endian(f
) != big
;
366 if (badness
< best
) {
371 if ((__force
int)best_format
>= 0)
374 return (__force snd_pcm_format_t
)-EINVAL
;
377 case SNDRV_PCM_FORMAT_MU_LAW
:
378 for (i
= 0; i
< ARRAY_SIZE(preferred_formats
); ++i
) {
379 snd_pcm_format_t format1
= preferred_formats
[i
];
380 if (snd_mask_test(format_mask
, (__force
int)format1
))
384 return (__force snd_pcm_format_t
)-EINVAL
;
389 int snd_pcm_plug_format_plugins(struct snd_pcm_substream
*plug
,
390 struct snd_pcm_hw_params
*params
,
391 struct snd_pcm_hw_params
*slave_params
)
393 struct snd_pcm_plugin_format tmpformat
;
394 struct snd_pcm_plugin_format dstformat
;
395 struct snd_pcm_plugin_format srcformat
;
396 snd_pcm_access_t src_access
, dst_access
;
397 struct snd_pcm_plugin
*plugin
= NULL
;
399 int stream
= snd_pcm_plug_stream(plug
);
400 int slave_interleaved
= (params_channels(slave_params
) == 1 ||
401 params_access(slave_params
) == SNDRV_PCM_ACCESS_RW_INTERLEAVED
);
404 case SNDRV_PCM_STREAM_PLAYBACK
:
405 dstformat
.format
= params_format(slave_params
);
406 dstformat
.rate
= params_rate(slave_params
);
407 dstformat
.channels
= params_channels(slave_params
);
408 srcformat
.format
= params_format(params
);
409 srcformat
.rate
= params_rate(params
);
410 srcformat
.channels
= params_channels(params
);
411 src_access
= SNDRV_PCM_ACCESS_RW_INTERLEAVED
;
412 dst_access
= (slave_interleaved
? SNDRV_PCM_ACCESS_RW_INTERLEAVED
:
413 SNDRV_PCM_ACCESS_RW_NONINTERLEAVED
);
415 case SNDRV_PCM_STREAM_CAPTURE
:
416 dstformat
.format
= params_format(params
);
417 dstformat
.rate
= params_rate(params
);
418 dstformat
.channels
= params_channels(params
);
419 srcformat
.format
= params_format(slave_params
);
420 srcformat
.rate
= params_rate(slave_params
);
421 srcformat
.channels
= params_channels(slave_params
);
422 src_access
= (slave_interleaved
? SNDRV_PCM_ACCESS_RW_INTERLEAVED
:
423 SNDRV_PCM_ACCESS_RW_NONINTERLEAVED
);
424 dst_access
= SNDRV_PCM_ACCESS_RW_INTERLEAVED
;
430 tmpformat
= srcformat
;
432 pdprintf("srcformat: format=%i, rate=%i, channels=%i\n",
436 pdprintf("dstformat: format=%i, rate=%i, channels=%i\n",
441 /* Format change (linearization) */
442 if (! rate_match(srcformat
.rate
, dstformat
.rate
) &&
443 ! snd_pcm_format_linear(srcformat
.format
)) {
444 if (srcformat
.format
!= SNDRV_PCM_FORMAT_MU_LAW
)
446 tmpformat
.format
= SNDRV_PCM_FORMAT_S16
;
447 err
= snd_pcm_plugin_build_mulaw(plug
,
448 &srcformat
, &tmpformat
,
452 err
= snd_pcm_plugin_append(plugin
);
454 snd_pcm_plugin_free(plugin
);
457 srcformat
= tmpformat
;
458 src_access
= dst_access
;
461 /* channels reduction */
462 if (srcformat
.channels
> dstformat
.channels
) {
463 tmpformat
.channels
= dstformat
.channels
;
464 err
= snd_pcm_plugin_build_route(plug
, &srcformat
, &tmpformat
, &plugin
);
465 pdprintf("channels reduction: src=%i, dst=%i returns %i\n", srcformat
.channels
, tmpformat
.channels
, err
);
468 err
= snd_pcm_plugin_append(plugin
);
470 snd_pcm_plugin_free(plugin
);
473 srcformat
= tmpformat
;
474 src_access
= dst_access
;
477 /* rate resampling */
478 if (!rate_match(srcformat
.rate
, dstformat
.rate
)) {
479 if (srcformat
.format
!= SNDRV_PCM_FORMAT_S16
) {
480 /* convert to S16 for resampling */
481 tmpformat
.format
= SNDRV_PCM_FORMAT_S16
;
482 err
= snd_pcm_plugin_build_linear(plug
,
483 &srcformat
, &tmpformat
,
487 err
= snd_pcm_plugin_append(plugin
);
489 snd_pcm_plugin_free(plugin
);
492 srcformat
= tmpformat
;
493 src_access
= dst_access
;
495 tmpformat
.rate
= dstformat
.rate
;
496 err
= snd_pcm_plugin_build_rate(plug
,
497 &srcformat
, &tmpformat
,
499 pdprintf("rate down resampling: src=%i, dst=%i returns %i\n", srcformat
.rate
, tmpformat
.rate
, err
);
502 err
= snd_pcm_plugin_append(plugin
);
504 snd_pcm_plugin_free(plugin
);
507 srcformat
= tmpformat
;
508 src_access
= dst_access
;
512 if (srcformat
.format
!= dstformat
.format
) {
513 tmpformat
.format
= dstformat
.format
;
514 if (srcformat
.format
== SNDRV_PCM_FORMAT_MU_LAW
||
515 tmpformat
.format
== SNDRV_PCM_FORMAT_MU_LAW
) {
516 err
= snd_pcm_plugin_build_mulaw(plug
,
517 &srcformat
, &tmpformat
,
520 else if (snd_pcm_format_linear(srcformat
.format
) &&
521 snd_pcm_format_linear(tmpformat
.format
)) {
522 err
= snd_pcm_plugin_build_linear(plug
,
523 &srcformat
, &tmpformat
,
528 pdprintf("format change: src=%i, dst=%i returns %i\n", srcformat
.format
, tmpformat
.format
, err
);
531 err
= snd_pcm_plugin_append(plugin
);
533 snd_pcm_plugin_free(plugin
);
536 srcformat
= tmpformat
;
537 src_access
= dst_access
;
540 /* channels extension */
541 if (srcformat
.channels
< dstformat
.channels
) {
542 tmpformat
.channels
= dstformat
.channels
;
543 err
= snd_pcm_plugin_build_route(plug
, &srcformat
, &tmpformat
, &plugin
);
544 pdprintf("channels extension: src=%i, dst=%i returns %i\n", srcformat
.channels
, tmpformat
.channels
, err
);
547 err
= snd_pcm_plugin_append(plugin
);
549 snd_pcm_plugin_free(plugin
);
552 srcformat
= tmpformat
;
553 src_access
= dst_access
;
557 if (src_access
!= dst_access
) {
558 err
= snd_pcm_plugin_build_copy(plug
,
562 pdprintf("interleave change (copy: returns %i)\n", err
);
565 err
= snd_pcm_plugin_append(plugin
);
567 snd_pcm_plugin_free(plugin
);
575 snd_pcm_sframes_t
snd_pcm_plug_client_channels_buf(struct snd_pcm_substream
*plug
,
577 snd_pcm_uframes_t count
,
578 struct snd_pcm_plugin_channel
**channels
)
580 struct snd_pcm_plugin
*plugin
;
581 struct snd_pcm_plugin_channel
*v
;
582 struct snd_pcm_plugin_format
*format
;
583 int width
, nchannels
, channel
;
584 int stream
= snd_pcm_plug_stream(plug
);
586 if (snd_BUG_ON(!buf
))
588 if (stream
== SNDRV_PCM_STREAM_PLAYBACK
) {
589 plugin
= snd_pcm_plug_first(plug
);
590 format
= &plugin
->src_format
;
592 plugin
= snd_pcm_plug_last(plug
);
593 format
= &plugin
->dst_format
;
595 v
= plugin
->buf_channels
;
597 if ((width
= snd_pcm_format_physical_width(format
->format
)) < 0)
599 nchannels
= format
->channels
;
600 if (snd_BUG_ON(plugin
->access
!= SNDRV_PCM_ACCESS_RW_INTERLEAVED
&&
601 format
->channels
> 1))
603 for (channel
= 0; channel
< nchannels
; channel
++, v
++) {
606 v
->wanted
= (stream
== SNDRV_PCM_STREAM_CAPTURE
);
608 v
->area
.first
= channel
* width
;
609 v
->area
.step
= nchannels
* width
;
614 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
)
616 struct snd_pcm_plugin
*plugin
, *next
;
617 struct snd_pcm_plugin_channel
*dst_channels
;
619 snd_pcm_sframes_t frames
= size
;
621 plugin
= snd_pcm_plug_first(plug
);
625 if ((next
= plugin
->next
) != NULL
) {
626 snd_pcm_sframes_t frames1
= frames
;
627 if (plugin
->dst_frames
) {
628 frames1
= plugin
->dst_frames(plugin
, frames
);
632 if ((err
= next
->client_channels(next
, frames1
, &dst_channels
)) < 0) {
635 if (err
!= frames1
) {
637 if (plugin
->src_frames
) {
638 frames
= plugin
->src_frames(plugin
, frames1
);
645 pdprintf("write plugin: %s, %li\n", plugin
->name
, frames
);
646 if ((frames
= plugin
->transfer(plugin
, src_channels
, dst_channels
, frames
)) < 0)
648 src_channels
= dst_channels
;
651 return plug_client_size(plug
, frames
, true);
654 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
)
656 struct snd_pcm_plugin
*plugin
, *next
;
657 struct snd_pcm_plugin_channel
*src_channels
, *dst_channels
;
658 snd_pcm_sframes_t frames
= size
;
661 frames
= plug_slave_size(plug
, frames
, true);
666 plugin
= snd_pcm_plug_first(plug
);
667 while (plugin
&& frames
> 0) {
668 if ((next
= plugin
->next
) != NULL
) {
669 if ((err
= plugin
->client_channels(plugin
, frames
, &dst_channels
)) < 0) {
674 dst_channels
= dst_channels_final
;
676 pdprintf("read plugin: %s, %li\n", plugin
->name
, frames
);
677 if ((frames
= plugin
->transfer(plugin
, src_channels
, dst_channels
, frames
)) < 0)
680 src_channels
= dst_channels
;
685 int snd_pcm_area_silence(const struct snd_pcm_channel_area
*dst_area
, size_t dst_offset
,
686 size_t samples
, snd_pcm_format_t format
)
688 /* FIXME: sub byte resolution and odd dst_offset */
690 unsigned int dst_step
;
692 const unsigned char *silence
;
695 dst
= dst_area
->addr
+ (dst_area
->first
+ dst_area
->step
* dst_offset
) / 8;
696 width
= snd_pcm_format_physical_width(format
);
699 if (dst_area
->step
== (unsigned int) width
&& width
>= 8)
700 return snd_pcm_format_set_silence(format
, dst
, samples
);
701 silence
= snd_pcm_format_silence_64(format
);
704 dst_step
= dst_area
->step
/ 8;
707 int dstbit
= dst_area
->first
% 8;
708 int dstbit_step
= dst_area
->step
% 8;
709 while (samples
-- > 0) {
715 dstbit
+= dstbit_step
;
723 while (samples
-- > 0) {
724 memcpy(dst
, silence
, width
);
731 int snd_pcm_area_copy(const struct snd_pcm_channel_area
*src_area
, size_t src_offset
,
732 const struct snd_pcm_channel_area
*dst_area
, size_t dst_offset
,
733 size_t samples
, snd_pcm_format_t format
)
735 /* FIXME: sub byte resolution and odd dst_offset */
738 int src_step
, dst_step
;
739 src
= src_area
->addr
+ (src_area
->first
+ src_area
->step
* src_offset
) / 8;
741 return snd_pcm_area_silence(dst_area
, dst_offset
, samples
, format
);
742 dst
= dst_area
->addr
+ (dst_area
->first
+ dst_area
->step
* dst_offset
) / 8;
745 width
= snd_pcm_format_physical_width(format
);
748 if (src_area
->step
== (unsigned int) width
&&
749 dst_area
->step
== (unsigned int) width
&& width
>= 8) {
750 size_t bytes
= samples
* width
/ 8;
751 memcpy(dst
, src
, bytes
);
754 src_step
= src_area
->step
/ 8;
755 dst_step
= dst_area
->step
/ 8;
758 int srcbit
= src_area
->first
% 8;
759 int srcbit_step
= src_area
->step
% 8;
760 int dstbit
= dst_area
->first
% 8;
761 int dstbit_step
= dst_area
->step
% 8;
762 while (samples
-- > 0) {
763 unsigned char srcval
;
765 srcval
= *src
& 0x0f;
767 srcval
= (*src
& 0xf0) >> 4;
769 *dst
= (*dst
& 0xf0) | srcval
;
771 *dst
= (*dst
& 0x0f) | (srcval
<< 4);
773 srcbit
+= srcbit_step
;
779 dstbit
+= dstbit_step
;
787 while (samples
-- > 0) {
788 memcpy(dst
, src
, width
);