/**
* \file include/control_external.h
* \brief External control plugin SDK
* \author Takashi Iwai <[email protected]>
* \date 2005
*
* External control plugin SDK.
*/
/*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser 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
*
*/
#ifndef __ALSA_CONTROL_EXTERNAL_H
#define __ALSA_CONTROL_EXTERNAL_H
#include "control.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
* \defgroup CtlPlugin_SDK External Control Plugin SDK
* \{
*/
/**
* Define the object entry for external control plugins
*/
#define SND_CTL_PLUGIN_ENTRY(name) _snd_ctl_##name##_open
/**
* Define the symbols of the given control plugin with versions
*/
#define SND_CTL_PLUGIN_SYMBOL(name) SND_DLSYM_BUILD_VERSION(SND_CTL_PLUGIN_ENTRY(name), SND_CONTROL_DLSYM_VERSION);
/**
* Define the control plugin
*/
#define SND_CTL_PLUGIN_DEFINE_FUNC(plugin) \
int SND_CTL_PLUGIN_ENTRY(plugin) (snd_ctl_t **handlep, const char *name,\
snd_config_t *root, snd_config_t *conf, int mode)
/** External control plugin handle */
typedef struct snd_ctl_ext snd_ctl_ext_t;
/** Callback table of control ext */
typedef struct snd_ctl_ext_callback snd_ctl_ext_callback_t;
/** Key to access a control pointer */
typedef unsigned long snd_ctl_ext_key_t;
#ifdef DOC_HIDDEN
/* redefine typedef's for stupid doxygen */
typedef snd_ctl_ext snd_ctl_ext_t;
typedef snd_ctl_ext_callback snd_ctl_ext_callback_t;
#endif
/** Callback to handle TLV commands. */
typedef int (snd_ctl_ext_tlv_rw_t)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, int op_flag, unsigned int numid,
unsigned int *tlv, unsigned int tlv_size);
/*
* Protocol version
*/
#define SND_CTL_EXT_VERSION_MAJOR 1 /**< Protocol major version */
#define SND_CTL_EXT_VERSION_MINOR 0 /**< Protocol minor version */
#define SND_CTL_EXT_VERSION_TINY 1 /**< Protocol tiny version */
/**
* external plugin protocol version
*/
#define SND_CTL_EXT_VERSION ((SND_CTL_EXT_VERSION_MAJOR<<16) |\
(SND_CTL_EXT_VERSION_MINOR<<8) |\
(SND_CTL_EXT_VERSION_TINY))
/** Handle of control ext */
struct snd_ctl_ext {
/**
* protocol version; #SND_CTL_EXT_VERSION must be filled here
* before calling #snd_ctl_ext_create()
*/
unsigned int version;
/**
* Index of this card; must be filled before calling #snd_ctl_ext_create()
*/
int card_idx;
/**
* ID string of this card; must be filled before calling #snd_ctl_ext_create()
*/
char id[16];
/**
* Driver name of this card; must be filled before calling #snd_ctl_ext_create()
*/
char driver[16];
/**
* short name of this card; must be filled before calling #snd_ctl_ext_create()
*/
char name[32];
/**
* Long name of this card; must be filled before calling #snd_ctl_ext_create()
*/
char longname[80];
/**
* Mixer name of this card; must be filled before calling #snd_ctl_ext_create()
*/
char mixername[80];
/**
* poll descriptor
*/
int poll_fd;
/**
* callbacks of this plugin; must be filled before calling #snd_pcm_ioplug_create()
*/
const snd_ctl_ext_callback_t *callback;
/**
* private data, which can be used freely in the driver callbacks
*/
void *private_data;
/**
* control handle filled by #snd_ctl_ext_create()
*/
snd_ctl_t *handle;
int nonblock; /**< non-block mode; read-only */
int subscribed; /**< events subscribed; read-only */
/**
* optional TLV data for the control (since protocol 1.0.1)
*/
union {
snd_ctl_ext_tlv_rw_t *c;
const unsigned int *p;
} tlv;
};
/** Callback table of ext. */
struct snd_ctl_ext_callback {
/**
* close the control handle; optional
*/
void (*close)(snd_ctl_ext_t *ext);
/**
* return the total number of elements; required
*/
int (*elem_count)(snd_ctl_ext_t *ext);
/**
* return the element id of the given offset (array index); required
*/
int (*elem_list)(snd_ctl_ext_t *ext, unsigned int offset, snd_ctl_elem_id_t *id);
/**
* convert the element id to a search key; required
*/
snd_ctl_ext_key_t (*find_elem)(snd_ctl_ext_t *ext, const snd_ctl_elem_id_t *id);
/**
* the destructor of the key; optional
*/
void (*free_key)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key);
/**
* get the attribute of the element; required
*/
int (*get_attribute)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key,
int *type, unsigned int *acc, unsigned int *count);
/**
* get the element information of integer type
*/
int (*get_integer_info)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key,
long *imin, long *imax, long *istep);
/**
* get the element information of integer64 type
*/
int (*get_integer64_info)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key,
int64_t *imin, int64_t *imax, int64_t *istep);
/**
* get the element information of enumerated type
*/
int (*get_enumerated_info)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, unsigned int *items);
/**
* get the name of the enumerated item
*/
int (*get_enumerated_name)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, unsigned int item,
char *name, size_t name_max_len);
/**
* read the current values of integer type
*/
int (*read_integer)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, long *value);
/**
* read the current values of integer64 type
*/
int (*read_integer64)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, int64_t *value);
/**
* read the current values of enumerated type
*/
int (*read_enumerated)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, unsigned int *items);
/**
* read the current values of bytes type
*/
int (*read_bytes)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, unsigned char *data,
size_t max_bytes);
/**
* read the current values of iec958 type
*/
int (*read_iec958)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, snd_aes_iec958_t *iec958);
/**
* update the current values of integer type with the given values
*/
int (*write_integer)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, long *value);
/**
* update the current values of integer64 type with the given values
*/
int (*write_integer64)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, int64_t *value);
/**
* update the current values of enumerated type with the given values
*/
int (*write_enumerated)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, unsigned int *items);
/**
* update the current values of bytes type with the given values
*/
int (*write_bytes)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, unsigned char *data,
size_t max_bytes);
/**
* update the current values of iec958 type with the given values
*/
int (*write_iec958)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key, snd_aes_iec958_t *iec958);
/**
* subscribe/unsubscribe the event notification; optional
*/
void (*subscribe_events)(snd_ctl_ext_t *ext, int subscribe);
/**
* read a pending notification event; optional
*/
int (*read_event)(snd_ctl_ext_t *ext, snd_ctl_elem_id_t *id, unsigned int *event_mask);
/**
* return the number of poll descriptors; optional
*/
int (*poll_descriptors_count)(snd_ctl_ext_t *ext);
/**
* fill the poll descriptors; optional
*/
int (*poll_descriptors)(snd_ctl_ext_t *ext, struct pollfd *pfds, unsigned int space);
/**
* mangle the revents of poll descriptors
*/
int (*poll_revents)(snd_ctl_ext_t *ext, struct pollfd *pfds, unsigned int nfds, unsigned short *revents);
};
/**
* The access type bits stored in get_attribute callback
*/
typedef enum snd_ctl_ext_access {
SND_CTL_EXT_ACCESS_READ = (1<<0),
SND_CTL_EXT_ACCESS_WRITE = (1<<1),
SND_CTL_EXT_ACCESS_READWRITE = (3<<0),
SND_CTL_EXT_ACCESS_VOLATILE = (1<<2),
SND_CTL_EXT_ACCESS_TLV_READ = (1<<4),
SND_CTL_EXT_ACCESS_TLV_WRITE = (1<<5),
SND_CTL_EXT_ACCESS_TLV_READWRITE = (3<<4),
SND_CTL_EXT_ACCESS_TLV_COMMAND = (1<<6),
SND_CTL_EXT_ACCESS_INACTIVE = (1<<8),
SND_CTL_EXT_ACCESS_TLV_CALLBACK = (1<<28),
} snd_ctl_ext_access_t;
/**
* find_elem callback returns this if no matching control element is found
*/
#define SND_CTL_EXT_KEY_NOT_FOUND (snd_ctl_ext_key_t)(-1)
int snd_ctl_ext_create(snd_ctl_ext_t *ext, const char *name, int mode);
int snd_ctl_ext_delete(snd_ctl_ext_t *ext);
/** \} */
#ifdef __cplusplus
}
#endif
#endif /* __ALSA_CONTROL_EXTERNAL_H */