Root/sound/core/oss/pcm_plugin.c

1/*
2 * PCM Plug-In shared (kernel/library) code
3 * Copyright (c) 1999 by Jaroslav Kysela <perex@perex.cz>
4 * Copyright (c) 2000 by Abramo Bagnara <abramo@alsa-project.org>
5 *
6 *
7 * This library is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU Library General Public License as
9 * published by the Free Software Foundation; either version 2 of
10 * the License, or (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU Library General Public License for more details.
16 *
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 *
21 */
22  
23#if 0
24#define PLUGIN_DEBUG
25#endif
26
27#include <linux/slab.h>
28#include <linux/time.h>
29#include <linux/vmalloc.h>
30#include <sound/core.h>
31#include <sound/pcm.h>
32#include <sound/pcm_params.h>
33#include "pcm_plugin.h"
34
35#define snd_pcm_plug_first(plug) ((plug)->runtime->oss.plugin_first)
36#define snd_pcm_plug_last(plug) ((plug)->runtime->oss.plugin_last)
37
38/*
39 * because some cards might have rates "very close", we ignore
40 * all "resampling" requests within +-5%
41 */
42static 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
49static 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
104int 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
138snd_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
146int 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
187int 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
199snd_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
229snd_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
267static 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
288static 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
309snd_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
359int 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
545snd_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
584snd_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
616snd_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
647int 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
693int 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}
757

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