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