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/*
* 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,1)
#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,1)
/*
* 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)
{
snd_assert(plugin != NULL, return -ENXIO);
snd_assert(src_channels != NULL, 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;
snd_assert(bufs != NULL, 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)
{
snd_assert(plugin != NULL, return -ENXIO);
snd_assert(dst_channels != NULL, 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;
snd_assert(bufs != NULL, 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;
snd_assert(r_plugin != NULL, return -ENXIO);
*r_plugin = NULL;
snd_assert(plug != NULL && params != NULL, 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;
}
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