|
Packit |
4a16fb |
/**
|
|
Packit |
4a16fb |
* \file pcm/pcm_asym.c
|
|
Packit |
4a16fb |
* \ingroup PCM_Plugins
|
|
Packit |
4a16fb |
* \brief PCM Asymmetrical Plugin Interface
|
|
Packit |
4a16fb |
* \author Takashi Iwai <tiwai@suse.de>
|
|
Packit |
4a16fb |
* \date 2003
|
|
Packit |
4a16fb |
*/
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
#include "pcm_local.h"
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
#ifndef PIC
|
|
Packit |
4a16fb |
/* entry for static linking */
|
|
Packit |
4a16fb |
const char *_snd_module_pcm_asym = "";
|
|
Packit |
4a16fb |
#endif
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
/*! \page pcm_plugins
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
\section pcm_plugins_asym Plugin: asym
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
This plugin is a combination of playback and capture PCM streams.
|
|
Packit |
4a16fb |
Slave PCMs can be defined asymmetrically for both directions.
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
\code
|
|
Packit |
4a16fb |
pcm.name {
|
|
Packit |
4a16fb |
type asym # Asym PCM
|
|
Packit |
4a16fb |
playback STR # Playback slave name
|
|
Packit |
4a16fb |
# or
|
|
Packit |
4a16fb |
playback { # Playback slave definition
|
|
Packit |
4a16fb |
pcm STR # Slave PCM name
|
|
Packit |
4a16fb |
# or
|
|
Packit |
4a16fb |
pcm { } # Slave PCM definition
|
|
Packit |
4a16fb |
}
|
|
Packit |
4a16fb |
capture STR # Capture slave name
|
|
Packit |
4a16fb |
# or
|
|
Packit |
4a16fb |
capture { # Capture slave definition
|
|
Packit |
4a16fb |
pcm STR # Slave PCM name
|
|
Packit |
4a16fb |
# or
|
|
Packit |
4a16fb |
pcm { } # Slave PCM definition
|
|
Packit |
4a16fb |
}
|
|
Packit |
4a16fb |
}
|
|
Packit |
4a16fb |
\endcode
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
For example, you can combine a dmix plugin and a dsnoop plugin as
|
|
Packit |
4a16fb |
as a single PCM for playback and capture directions, respectively.
|
|
Packit |
4a16fb |
\code
|
|
Packit |
4a16fb |
pcm.duplex {
|
|
Packit |
4a16fb |
type asym
|
|
Packit |
4a16fb |
playback.pcm "dmix"
|
|
Packit |
4a16fb |
capture.pcm "dsnoop"
|
|
Packit |
4a16fb |
}
|
|
Packit |
4a16fb |
\endcode
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
By defining only a single direction, the resultant PCM becomes
|
|
Packit |
4a16fb |
half-duplex.
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
\subsection pcm_plugins_asym_funcref Function reference
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
_snd_pcm_asym_open()
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
*/
|
|
Packit |
4a16fb |
|
|
Packit |
4a16fb |
/**
|
|
Packit |
4a16fb |
* \brief Creates a new asym stream PCM
|
|
Packit |
4a16fb |
* \param pcmp Returns created PCM handle
|
|
Packit |
4a16fb |
* \param name Name of PCM
|
|
Packit |
4a16fb |
* \param root Root configuration node
|
|
Packit |
4a16fb |
* \param conf Configuration node with copy PCM description
|
|
Packit |
4a16fb |
* \param stream Stream type
|
|
Packit |
4a16fb |
* \param mode Stream mode
|
|
Packit |
4a16fb |
* \retval zero on success otherwise a negative error code
|
|
Packit |
4a16fb |
* \warning Using of this function might be dangerous in the sense
|
|
Packit |
4a16fb |
* of compatibility reasons. The prototype might be freely
|
|
Packit |
4a16fb |
* changed in future.
|
|
Packit |
4a16fb |
*/
|
|
Packit |
4a16fb |
int _snd_pcm_asym_open(snd_pcm_t **pcmp, const char *name ATTRIBUTE_UNUSED,
|
|
Packit |
4a16fb |
snd_config_t *root, snd_config_t *conf,
|
|
Packit |
4a16fb |
snd_pcm_stream_t stream, int mode)
|
|
Packit |
4a16fb |
{
|
|
Packit |
4a16fb |
snd_config_iterator_t i, next;
|
|
Packit |
4a16fb |
int err;
|
|
Packit |
4a16fb |
snd_config_t *slave = NULL, *sconf;
|
|
Packit |
4a16fb |
snd_config_for_each(i, next, conf) {
|
|
Packit |
4a16fb |
snd_config_t *n = snd_config_iterator_entry(i);
|
|
Packit |
4a16fb |
const char *id;
|
|
Packit |
4a16fb |
if (snd_config_get_id(n, &id) < 0)
|
|
Packit |
4a16fb |
continue;
|
|
Packit |
4a16fb |
if (snd_pcm_conf_generic_id(id))
|
|
Packit |
4a16fb |
continue;
|
|
Packit |
4a16fb |
if (strcmp(id, "playback") == 0) {
|
|
Packit |
4a16fb |
if (stream == SND_PCM_STREAM_PLAYBACK)
|
|
Packit |
4a16fb |
slave = n;
|
|
Packit |
4a16fb |
continue;
|
|
Packit |
4a16fb |
}
|
|
Packit |
4a16fb |
if (strcmp(id, "capture") == 0) {
|
|
Packit |
4a16fb |
if (stream == SND_PCM_STREAM_CAPTURE)
|
|
Packit |
4a16fb |
slave = n;
|
|
Packit |
4a16fb |
continue;
|
|
Packit |
4a16fb |
}
|
|
Packit |
4a16fb |
SNDERR("Unknown field %s", id);
|
|
Packit |
4a16fb |
return -EINVAL;
|
|
Packit |
4a16fb |
}
|
|
Packit |
4a16fb |
if (! slave) {
|
|
Packit |
4a16fb |
SNDERR("%s slave is not defined",
|
|
Packit |
4a16fb |
stream == SND_PCM_STREAM_PLAYBACK ? "playback" : "capture");
|
|
Packit |
4a16fb |
return -EINVAL;
|
|
Packit |
4a16fb |
}
|
|
Packit |
4a16fb |
err = snd_pcm_slave_conf(root, slave, &sconf, 0);
|
|
Packit |
4a16fb |
if (err < 0)
|
|
Packit |
4a16fb |
return err;
|
|
Packit |
4a16fb |
err = snd_pcm_open_named_slave(pcmp, name, root, sconf, stream,
|
|
Packit |
4a16fb |
mode, conf);
|
|
Packit |
4a16fb |
snd_config_delete(sconf);
|
|
Packit |
4a16fb |
return err;
|
|
Packit |
4a16fb |
}
|
|
Packit |
4a16fb |
#ifndef DOC_HIDDEN
|
|
Packit |
4a16fb |
SND_DLSYM_BUILD_VERSION(_snd_pcm_asym_open, SND_PCM_DLSYM_VERSION);
|
|
Packit |
4a16fb |
#endif
|