142 строки
4.3 KiB
C
142 строки
4.3 KiB
C
/*
|
|
* PCM I/O Plug-In Interface
|
|
* Copyright (c) 1999 by Jaroslav Kysela <perex@perex.cz>
|
|
*
|
|
*
|
|
* This library is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU Library General Public License as
|
|
* published by the Free Software Foundation; either version 2 of
|
|
* the License, or (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU Library General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Library General Public
|
|
* License along with this library; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*
|
|
*/
|
|
|
|
#include <linux/time.h>
|
|
#include <sound/core.h>
|
|
#include <sound/pcm.h>
|
|
#include <sound/pcm_params.h>
|
|
#include "pcm_plugin.h"
|
|
|
|
#define pcm_write(plug,buf,count) snd_pcm_oss_write3(plug,buf,count,1)
|
|
#define pcm_writev(plug,vec,count) snd_pcm_oss_writev3(plug,vec,count)
|
|
#define pcm_read(plug,buf,count) snd_pcm_oss_read3(plug,buf,count,1)
|
|
#define pcm_readv(plug,vec,count) snd_pcm_oss_readv3(plug,vec,count)
|
|
|
|
/*
|
|
* Basic io plugin
|
|
*/
|
|
|
|
static snd_pcm_sframes_t io_playback_transfer(struct snd_pcm_plugin *plugin,
|
|
const struct snd_pcm_plugin_channel *src_channels,
|
|
struct snd_pcm_plugin_channel *dst_channels,
|
|
snd_pcm_uframes_t frames)
|
|
{
|
|
if (snd_BUG_ON(!plugin))
|
|
return -ENXIO;
|
|
if (snd_BUG_ON(!src_channels))
|
|
return -ENXIO;
|
|
if (plugin->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED) {
|
|
return pcm_write(plugin->plug, src_channels->area.addr, frames);
|
|
} else {
|
|
int channel, channels = plugin->dst_format.channels;
|
|
void **bufs = (void**)plugin->extra_data;
|
|
if (snd_BUG_ON(!bufs))
|
|
return -ENXIO;
|
|
for (channel = 0; channel < channels; channel++) {
|
|
if (src_channels[channel].enabled)
|
|
bufs[channel] = src_channels[channel].area.addr;
|
|
else
|
|
bufs[channel] = NULL;
|
|
}
|
|
return pcm_writev(plugin->plug, bufs, frames);
|
|
}
|
|
}
|
|
|
|
static snd_pcm_sframes_t io_capture_transfer(struct snd_pcm_plugin *plugin,
|
|
const struct snd_pcm_plugin_channel *src_channels,
|
|
struct snd_pcm_plugin_channel *dst_channels,
|
|
snd_pcm_uframes_t frames)
|
|
{
|
|
if (snd_BUG_ON(!plugin))
|
|
return -ENXIO;
|
|
if (snd_BUG_ON(!dst_channels))
|
|
return -ENXIO;
|
|
if (plugin->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED) {
|
|
return pcm_read(plugin->plug, dst_channels->area.addr, frames);
|
|
} else {
|
|
int channel, channels = plugin->dst_format.channels;
|
|
void **bufs = (void**)plugin->extra_data;
|
|
if (snd_BUG_ON(!bufs))
|
|
return -ENXIO;
|
|
for (channel = 0; channel < channels; channel++) {
|
|
if (dst_channels[channel].enabled)
|
|
bufs[channel] = dst_channels[channel].area.addr;
|
|
else
|
|
bufs[channel] = NULL;
|
|
}
|
|
return pcm_readv(plugin->plug, bufs, frames);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static snd_pcm_sframes_t io_src_channels(struct snd_pcm_plugin *plugin,
|
|
snd_pcm_uframes_t frames,
|
|
struct snd_pcm_plugin_channel **channels)
|
|
{
|
|
int err;
|
|
unsigned int channel;
|
|
struct snd_pcm_plugin_channel *v;
|
|
err = snd_pcm_plugin_client_channels(plugin, frames, &v);
|
|
if (err < 0)
|
|
return err;
|
|
*channels = v;
|
|
if (plugin->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED) {
|
|
for (channel = 0; channel < plugin->src_format.channels; ++channel, ++v)
|
|
v->wanted = 1;
|
|
}
|
|
return frames;
|
|
}
|
|
|
|
int snd_pcm_plugin_build_io(struct snd_pcm_substream *plug,
|
|
struct snd_pcm_hw_params *params,
|
|
struct snd_pcm_plugin **r_plugin)
|
|
{
|
|
int err;
|
|
struct snd_pcm_plugin_format format;
|
|
struct snd_pcm_plugin *plugin;
|
|
|
|
if (snd_BUG_ON(!r_plugin))
|
|
return -ENXIO;
|
|
*r_plugin = NULL;
|
|
if (snd_BUG_ON(!plug || !params))
|
|
return -ENXIO;
|
|
format.format = params_format(params);
|
|
format.rate = params_rate(params);
|
|
format.channels = params_channels(params);
|
|
err = snd_pcm_plugin_build(plug, "I/O io",
|
|
&format, &format,
|
|
sizeof(void *) * format.channels,
|
|
&plugin);
|
|
if (err < 0)
|
|
return err;
|
|
plugin->access = params_access(params);
|
|
if (snd_pcm_plug_stream(plug) == SNDRV_PCM_STREAM_PLAYBACK) {
|
|
plugin->transfer = io_playback_transfer;
|
|
if (plugin->access == SNDRV_PCM_ACCESS_RW_INTERLEAVED)
|
|
plugin->client_channels = io_src_channels;
|
|
} else {
|
|
plugin->transfer = io_capture_transfer;
|
|
}
|
|
|
|
*r_plugin = plugin;
|
|
return 0;
|
|
}
|