mirrors/alsa-lib
1
0
Fork 0
mirror of https://github.com/alsa-project/alsa-lib.git synced 2025-10-29 05:40:25 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions

Add detailed documentation for external control plugin SDK

Browse source 
Added the detailed documentation for external control plugin SDK.
This commit is contained in:
Takashi Iwai 2005-06-13 13:19:03 +00:00
parent 555b870760
commit 3656a66397
4 changed files with 300 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

101
include/control_external.h
View file

@ -33,7 +33,7 @@ extern "C" {
#endif
/**
* \defgroup CtlPlugin_SDK External control plugin SDK
* \defgroup CtlPlugin_SDK External Control Plugin SDK
* \{
*/
@ -129,47 +129,128 @@ struct snd_ctl_ext {
/** Callback table of ext */
struct snd_ctl_ext_callback {
void (*close)(snd_ctl_ext_t *ext); /* opt */
void (*subscribe_events)(snd_ctl_ext_t *ext, int subscribe); /* opt */
int (*elem_count)(snd_ctl_ext_t *ext); /* req */
int (*elem_list)(snd_ctl_ext_t *ext, unsigned int offset, snd_ctl_elem_id_t *id); /* req */
snd_ctl_ext_key_t (*find_elem)(snd_ctl_ext_t *ext, const snd_ctl_elem_id_t *id); /* req */
void (*free_key)(snd_ctl_ext_t *ext, snd_ctl_ext_key_t key); /* opt */
/**
* 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); /* req */
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);
};
enum snd_ctl_ext_access_t {
/**
* 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_INACTIVE = (1<<8),
};
} 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);