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Commit | Line | Data |
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1da177e4 | 1 | /* |
0534ab42 | 2 | * Route Plug-In |
1da177e4 LT |
3 | * Copyright (c) 2000 by Abramo Bagnara <abramo@alsa-project.org> |
4 | * | |
5 | * | |
6 | * This library is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU Library General Public License as | |
8 | * published by the Free Software Foundation; either version 2 of | |
9 | * the License, or (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU Library General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU Library General Public | |
17 | * License along with this library; if not, write to the Free Software | |
18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
19 | * | |
20 | */ | |
21 | ||
1da177e4 LT |
22 | #include <linux/time.h> |
23 | #include <sound/core.h> | |
24 | #include <sound/pcm.h> | |
25 | #include "pcm_plugin.h" | |
26 | ||
0534ab42 TI |
27 | static void zero_areas(struct snd_pcm_plugin_channel *dvp, int ndsts, |
28 | snd_pcm_uframes_t frames, int format) | |
1da177e4 | 29 | { |
0534ab42 TI |
30 | int dst = 0; |
31 | for (; dst < ndsts; ++dst) { | |
32 | if (dvp->wanted) | |
33 | snd_pcm_area_silence(&dvp->area, 0, frames, format); | |
34 | dvp->enabled = 0; | |
35 | dvp++; | |
1da177e4 LT |
36 | } |
37 | } | |
38 | ||
0534ab42 | 39 | static inline void copy_area(const struct snd_pcm_plugin_channel *src_channel, |
6ac77bc1 | 40 | struct snd_pcm_plugin_channel *dst_channel, |
0534ab42 | 41 | snd_pcm_uframes_t frames, int format) |
1da177e4 | 42 | { |
1da177e4 | 43 | dst_channel->enabled = 1; |
0534ab42 | 44 | snd_pcm_area_copy(&src_channel->area, 0, &dst_channel->area, 0, frames, format); |
1da177e4 LT |
45 | } |
46 | ||
6ac77bc1 | 47 | static snd_pcm_sframes_t route_transfer(struct snd_pcm_plugin *plugin, |
0534ab42 TI |
48 | const struct snd_pcm_plugin_channel *src_channels, |
49 | struct snd_pcm_plugin_channel *dst_channels, | |
50 | snd_pcm_uframes_t frames) | |
1da177e4 | 51 | { |
0534ab42 | 52 | int nsrcs, ndsts, dst; |
6ac77bc1 | 53 | struct snd_pcm_plugin_channel *dvp; |
0534ab42 | 54 | int format; |
1da177e4 | 55 | |
7eaa943c TI |
56 | if (snd_BUG_ON(!plugin || !src_channels || !dst_channels)) |
57 | return -ENXIO; | |
1da177e4 LT |
58 | if (frames == 0) |
59 | return 0; | |
1da177e4 | 60 | |
0534ab42 TI |
61 | nsrcs = plugin->src_format.channels; |
62 | ndsts = plugin->dst_format.channels; | |
1da177e4 | 63 | |
0534ab42 TI |
64 | format = plugin->dst_format.format; |
65 | dvp = dst_channels; | |
66 | if (nsrcs <= 1) { | |
67 | /* expand to all channels */ | |
68 | for (dst = 0; dst < ndsts; ++dst) { | |
69 | copy_area(src_channels, dvp, frames, format); | |
70 | dvp++; | |
1da177e4 | 71 | } |
0534ab42 | 72 | return frames; |
1da177e4 | 73 | } |
1da177e4 | 74 | |
0534ab42 TI |
75 | for (dst = 0; dst < ndsts && dst < nsrcs; ++dst) { |
76 | copy_area(src_channels, dvp, frames, format); | |
1da177e4 | 77 | dvp++; |
0534ab42 | 78 | src_channels++; |
1da177e4 | 79 | } |
0534ab42 TI |
80 | if (dst < ndsts) |
81 | zero_areas(dvp, ndsts - dst, frames, format); | |
1da177e4 LT |
82 | return frames; |
83 | } | |
84 | ||
6ac77bc1 TI |
85 | int snd_pcm_plugin_build_route(struct snd_pcm_substream *plug, |
86 | struct snd_pcm_plugin_format *src_format, | |
87 | struct snd_pcm_plugin_format *dst_format, | |
6ac77bc1 | 88 | struct snd_pcm_plugin **r_plugin) |
1da177e4 | 89 | { |
6ac77bc1 | 90 | struct snd_pcm_plugin *plugin; |
1da177e4 LT |
91 | int err; |
92 | ||
7eaa943c TI |
93 | if (snd_BUG_ON(!r_plugin)) |
94 | return -ENXIO; | |
1da177e4 | 95 | *r_plugin = NULL; |
7eaa943c TI |
96 | if (snd_BUG_ON(src_format->rate != dst_format->rate)) |
97 | return -ENXIO; | |
98 | if (snd_BUG_ON(src_format->format != dst_format->format)) | |
99 | return -ENXIO; | |
1da177e4 | 100 | |
0534ab42 TI |
101 | err = snd_pcm_plugin_build(plug, "route conversion", |
102 | src_format, dst_format, 0, &plugin); | |
1da177e4 LT |
103 | if (err < 0) |
104 | return err; | |
105 | ||
1da177e4 | 106 | plugin->transfer = route_transfer; |
1da177e4 LT |
107 | *r_plugin = plugin; |
108 | return 0; | |
109 | } |