1 | /* |
2 | * PCM I/O Plug-In Interface |
3 | * Copyright (c) 1999 by Jaroslav Kysela <perex@perex.cz> |
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 | |
22 | #include <linux/time.h> |
23 | #include <sound/core.h> |
24 | #include <sound/pcm.h> |
25 | #include <sound/pcm_params.h> |
26 | #include "pcm_plugin.h" |
27 | |
28 | #define pcm_write(plug,buf,count) snd_pcm_oss_write3(plug,buf,count,1) |
29 | #define pcm_writev(plug,vec,count) snd_pcm_oss_writev3(plug,vec,count) |
30 | #define pcm_read(plug,buf,count) snd_pcm_oss_read3(plug,buf,count,1) |
31 | #define pcm_readv(plug,vec,count) snd_pcm_oss_readv3(plug,vec,count) |
32 | |
33 | /* |
34 | * Basic io plugin |
35 | */ |
36 | |
37 | static snd_pcm_sframes_t io_playback_transfer(struct snd_pcm_plugin *plugin, |
38 | const struct snd_pcm_plugin_channel *src_channels, |
39 | struct snd_pcm_plugin_channel *dst_channels, |
40 | snd_pcm_uframes_t frames) |
41 | { |
42 | if (snd_BUG_ON(!plugin)) |
43 | return -ENXIO; |
44 | if (snd_BUG_ON(!src_channels)) |
45 | return -ENXIO; |
46 | if (plugin->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED) { |
47 | return pcm_write(plugin->plug, src_channels->area.addr, frames); |
48 | } else { |
49 | int channel, channels = plugin->dst_format.channels; |
50 | void **bufs = (void**)plugin->extra_data; |
51 | if (snd_BUG_ON(!bufs)) |
52 | return -ENXIO; |
53 | for (channel = 0; channel < channels; channel++) { |
54 | if (src_channels[channel].enabled) |
55 | bufs[channel] = src_channels[channel].area.addr; |
56 | else |
57 | bufs[channel] = NULL; |
58 | } |
59 | return pcm_writev(plugin->plug, bufs, frames); |
60 | } |
61 | } |
62 | |
63 | static snd_pcm_sframes_t io_capture_transfer(struct snd_pcm_plugin *plugin, |
64 | const struct snd_pcm_plugin_channel *src_channels, |
65 | struct snd_pcm_plugin_channel *dst_channels, |
66 | snd_pcm_uframes_t frames) |
67 | { |
68 | if (snd_BUG_ON(!plugin)) |
69 | return -ENXIO; |
70 | if (snd_BUG_ON(!dst_channels)) |
71 | return -ENXIO; |
72 | if (plugin->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED) { |
73 | return pcm_read(plugin->plug, dst_channels->area.addr, frames); |
74 | } else { |
75 | int channel, channels = plugin->dst_format.channels; |
76 | void **bufs = (void**)plugin->extra_data; |
77 | if (snd_BUG_ON(!bufs)) |
78 | return -ENXIO; |
79 | for (channel = 0; channel < channels; channel++) { |
80 | if (dst_channels[channel].enabled) |
81 | bufs[channel] = dst_channels[channel].area.addr; |
82 | else |
83 | bufs[channel] = NULL; |
84 | } |
85 | return pcm_readv(plugin->plug, bufs, frames); |
86 | } |
87 | return 0; |
88 | } |
89 | |
90 | static snd_pcm_sframes_t io_src_channels(struct snd_pcm_plugin *plugin, |
91 | snd_pcm_uframes_t frames, |
92 | struct snd_pcm_plugin_channel **channels) |
93 | { |
94 | int err; |
95 | unsigned int channel; |
96 | struct snd_pcm_plugin_channel *v; |
97 | err = snd_pcm_plugin_client_channels(plugin, frames, channels: &v); |
98 | if (err < 0) |
99 | return err; |
100 | *channels = v; |
101 | if (plugin->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED) { |
102 | for (channel = 0; channel < plugin->src_format.channels; ++channel, ++v) |
103 | v->wanted = 1; |
104 | } |
105 | return frames; |
106 | } |
107 | |
108 | int snd_pcm_plugin_build_io(struct snd_pcm_substream *plug, |
109 | struct snd_pcm_hw_params *params, |
110 | struct snd_pcm_plugin **r_plugin) |
111 | { |
112 | int err; |
113 | struct snd_pcm_plugin_format format; |
114 | struct snd_pcm_plugin *plugin; |
115 | |
116 | if (snd_BUG_ON(!r_plugin)) |
117 | return -ENXIO; |
118 | *r_plugin = NULL; |
119 | if (snd_BUG_ON(!plug || !params)) |
120 | return -ENXIO; |
121 | format.format = params_format(p: params); |
122 | format.rate = params_rate(p: params); |
123 | format.channels = params_channels(p: params); |
124 | err = snd_pcm_plugin_build(handle: plug, name: "I/O io" , |
125 | src_format: &format, dst_format: &format, |
126 | extra: sizeof(void *) * format.channels, |
127 | ret: &plugin); |
128 | if (err < 0) |
129 | return err; |
130 | plugin->access = params_access(p: params); |
131 | if (snd_pcm_plug_stream(plug) == SNDRV_PCM_STREAM_PLAYBACK) { |
132 | plugin->transfer = io_playback_transfer; |
133 | if (plugin->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED) |
134 | plugin->client_channels = io_src_channels; |
135 | } else { |
136 | plugin->transfer = io_capture_transfer; |
137 | } |
138 | |
139 | *r_plugin = plugin; |
140 | return 0; |
141 | } |
142 | |