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Simple Mixer Interface

Data Structures

struct  snd_mixer_selem_regopt
 

Macros

#define snd_mixer_selem_id_alloca(ptr)
 allocate an invalid snd_mixer_selem_id_t using standard alloca More...
 

Typedefs

typedef struct _snd_mixer_selem_id snd_mixer_selem_id_t
 

Enumerations

enum  snd_mixer_selem_channel_id_t {
  SND_MIXER_SCHN_UNKNOWN = -1, SND_MIXER_SCHN_FRONT_LEFT = 0, SND_MIXER_SCHN_FRONT_RIGHT, SND_MIXER_SCHN_REAR_LEFT,
  SND_MIXER_SCHN_REAR_RIGHT, SND_MIXER_SCHN_FRONT_CENTER, SND_MIXER_SCHN_WOOFER, SND_MIXER_SCHN_SIDE_LEFT,
  SND_MIXER_SCHN_SIDE_RIGHT, SND_MIXER_SCHN_REAR_CENTER, SND_MIXER_SCHN_LAST = 31, SND_MIXER_SCHN_MONO = SND_MIXER_SCHN_FRONT_LEFT
}
 
enum  snd_mixer_selem_regopt_abstract { SND_MIXER_SABSTRACT_NONE = 0, SND_MIXER_SABSTRACT_BASIC }
 

Functions

const char * snd_mixer_selem_channel_name (snd_mixer_selem_channel_id_t channel)
 Return name of mixer simple element channel. More...
 
int snd_mixer_selem_register (snd_mixer_t *mixer, struct snd_mixer_selem_regopt *options, snd_mixer_class_t **classp)
 Register mixer simple element class. More...
 
void snd_mixer_selem_get_id (snd_mixer_elem_t *element, snd_mixer_selem_id_t *id)
 Get mixer simple element identifier. More...
 
const char * snd_mixer_selem_get_name (snd_mixer_elem_t *elem)
 Get name part of mixer simple element identifier. More...
 
unsigned int snd_mixer_selem_get_index (snd_mixer_elem_t *elem)
 Get index part of mixer simple element identifier. More...
 
snd_mixer_elem_tsnd_mixer_find_selem (snd_mixer_t *mixer, const snd_mixer_selem_id_t *id)
 Find a mixer simple element. More...
 
int snd_mixer_selem_is_active (snd_mixer_elem_t *elem)
 Get info about the active state of a mixer simple element. More...
 
int snd_mixer_selem_is_playback_mono (snd_mixer_elem_t *elem)
 Get info about channels of playback stream of a mixer simple element. More...
 
int snd_mixer_selem_has_playback_channel (snd_mixer_elem_t *obj, snd_mixer_selem_channel_id_t channel)
 Get info about channels of playback stream of a mixer simple element. More...
 
int snd_mixer_selem_is_capture_mono (snd_mixer_elem_t *elem)
 Get info about channels of capture stream of a mixer simple element. More...
 
int snd_mixer_selem_has_capture_channel (snd_mixer_elem_t *obj, snd_mixer_selem_channel_id_t channel)
 Get info about channels of capture stream of a mixer simple element. More...
 
int snd_mixer_selem_get_capture_group (snd_mixer_elem_t *elem)
 Return info about capture switch control of a mixer simple element. More...
 
int snd_mixer_selem_has_common_volume (snd_mixer_elem_t *elem)
 Return true if mixer simple element has only one volume control for both playback and capture. More...
 
int snd_mixer_selem_has_playback_volume (snd_mixer_elem_t *elem)
 Return info about playback volume control of a mixer simple element. More...
 
int snd_mixer_selem_has_playback_volume_joined (snd_mixer_elem_t *elem)
 Return info about playback volume control of a mixer simple element. More...
 
int snd_mixer_selem_has_capture_volume (snd_mixer_elem_t *elem)
 Return info about capture volume control of a mixer simple element. More...
 
int snd_mixer_selem_has_capture_volume_joined (snd_mixer_elem_t *elem)
 Return info about capture volume control of a mixer simple element. More...
 
int snd_mixer_selem_has_common_switch (snd_mixer_elem_t *elem)
 Return true if mixer simple element has only one switch control for both playback and capture. More...
 
int snd_mixer_selem_has_playback_switch (snd_mixer_elem_t *elem)
 Return info about playback switch control existence of a mixer simple element. More...
 
int snd_mixer_selem_has_playback_switch_joined (snd_mixer_elem_t *elem)
 Return info about playback switch control of a mixer simple element. More...
 
int snd_mixer_selem_has_capture_switch (snd_mixer_elem_t *elem)
 Return info about capture switch control existence of a mixer simple element. More...
 
int snd_mixer_selem_has_capture_switch_joined (snd_mixer_elem_t *elem)
 Return info about capture switch control of a mixer simple element. More...
 
int snd_mixer_selem_has_capture_switch_exclusive (snd_mixer_elem_t *elem)
 Return info about capture switch control of a mixer simple element. More...
 
int snd_mixer_selem_ask_playback_vol_dB (snd_mixer_elem_t *elem, long value, long *dBvalue)
 Return corresponding dB value to an integer playback volume for a mixer simple element. More...
 
int snd_mixer_selem_ask_capture_vol_dB (snd_mixer_elem_t *elem, long value, long *dBvalue)
 Return corresponding dB value to an integer capture volume for a mixer simple element. More...
 
int snd_mixer_selem_ask_playback_dB_vol (snd_mixer_elem_t *elem, long dBvalue, int dir, long *value)
 Return corresponding integer playback volume for given dB value for a mixer simple element. More...
 
int snd_mixer_selem_ask_capture_dB_vol (snd_mixer_elem_t *elem, long dBvalue, int dir, long *value)
 Return corresponding integer capture volume for given dB value for a mixer simple element. More...
 
int snd_mixer_selem_get_playback_volume (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long *value)
 Return value of playback volume control of a mixer simple element. More...
 
int snd_mixer_selem_get_capture_volume (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long *value)
 Return value of capture volume control of a mixer simple element. More...
 
int snd_mixer_selem_get_playback_dB (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long *value)
 Return value of playback volume in dB control of a mixer simple element. More...
 
int snd_mixer_selem_get_capture_dB (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long *value)
 Return value of capture volume in dB control of a mixer simple element. More...
 
int snd_mixer_selem_get_playback_switch (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, int *value)
 Return value of playback switch control of a mixer simple element. More...
 
int snd_mixer_selem_get_capture_switch (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, int *value)
 Return value of capture switch control of a mixer simple element. More...
 
int snd_mixer_selem_set_playback_volume (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long value)
 Set value of playback volume control of a mixer simple element. More...
 
int snd_mixer_selem_set_capture_volume (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long value)
 Set value of capture volume control of a mixer simple element. More...
 
int snd_mixer_selem_set_playback_dB (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long value, int dir)
 Set value in dB of playback volume control of a mixer simple element. More...
 
int snd_mixer_selem_set_capture_dB (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long value, int dir)
 Set value in dB of capture volume control of a mixer simple element. More...
 
int snd_mixer_selem_set_playback_volume_all (snd_mixer_elem_t *elem, long value)
 Set value of playback volume control for all channels of a mixer simple element. More...
 
int snd_mixer_selem_set_capture_volume_all (snd_mixer_elem_t *elem, long value)
 Set value of capture volume control for all channels of a mixer simple element. More...
 
int snd_mixer_selem_set_playback_dB_all (snd_mixer_elem_t *elem, long value, int dir)
 Set value in dB of playback volume control for all channels of a mixer simple element. More...
 
int snd_mixer_selem_set_capture_dB_all (snd_mixer_elem_t *elem, long value, int dir)
 Set value in dB of capture volume control for all channels of a mixer simple element. More...
 
int snd_mixer_selem_set_playback_switch (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, int value)
 Set value of playback switch control of a mixer simple element. More...
 
int snd_mixer_selem_set_capture_switch (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, int value)
 Set value of capture switch control of a mixer simple element. More...
 
int snd_mixer_selem_set_playback_switch_all (snd_mixer_elem_t *elem, int value)
 Set value of playback switch control for all channels of a mixer simple element. More...
 
int snd_mixer_selem_set_capture_switch_all (snd_mixer_elem_t *elem, int value)
 Set value of capture switch control for all channels of a mixer simple element. More...
 
int snd_mixer_selem_get_playback_volume_range (snd_mixer_elem_t *elem, long *min, long *max)
 Get range for playback volume of a mixer simple element. More...
 
int snd_mixer_selem_get_playback_dB_range (snd_mixer_elem_t *elem, long *min, long *max)
 Get range in dB for playback volume of a mixer simple element. More...
 
int snd_mixer_selem_set_playback_volume_range (snd_mixer_elem_t *elem, long min, long max)
 Set range for playback volume of a mixer simple element. More...
 
int snd_mixer_selem_get_capture_volume_range (snd_mixer_elem_t *elem, long *min, long *max)
 Get range for capture volume of a mixer simple element. More...
 
int snd_mixer_selem_get_capture_dB_range (snd_mixer_elem_t *elem, long *min, long *max)
 Get range in dB for capture volume of a mixer simple element. More...
 
int snd_mixer_selem_set_capture_volume_range (snd_mixer_elem_t *elem, long min, long max)
 Set range for capture volume of a mixer simple element. More...
 
int snd_mixer_selem_is_enumerated (snd_mixer_elem_t *elem)
 Return true if mixer simple element is an enumerated control. More...
 
int snd_mixer_selem_is_enum_playback (snd_mixer_elem_t *elem)
 Return true if mixer simple enumerated element belongs to the playback direction. More...
 
int snd_mixer_selem_is_enum_capture (snd_mixer_elem_t *elem)
 Return true if mixer simple enumerated element belongs to the capture direction. More...
 
int snd_mixer_selem_get_enum_items (snd_mixer_elem_t *elem)
 Return the number of enumerated items of the given mixer simple element. More...
 
int snd_mixer_selem_get_enum_item_name (snd_mixer_elem_t *elem, unsigned int idx, size_t maxlen, char *str)
 get the enumerated item string for the given mixer simple element More...
 
int snd_mixer_selem_get_enum_item (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, unsigned int *idxp)
 get the current selected enumerated item for the given mixer simple element More...
 
int snd_mixer_selem_set_enum_item (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, unsigned int idx)
 set the current selected enumerated item for the given mixer simple element More...
 
size_t snd_mixer_selem_id_sizeof (void)
 get size of snd_mixer_selem_id_t More...
 
int snd_mixer_selem_id_malloc (snd_mixer_selem_id_t **ptr)
 allocate an invalid snd_mixer_selem_id_t using standard malloc More...
 
void snd_mixer_selem_id_free (snd_mixer_selem_id_t *obj)
 frees a previously allocated snd_mixer_selem_id_t More...
 
void snd_mixer_selem_id_copy (snd_mixer_selem_id_t *dst, const snd_mixer_selem_id_t *src)
 copy one snd_mixer_selem_id_t to another More...
 
const char * snd_mixer_selem_id_get_name (const snd_mixer_selem_id_t *obj)
 Get name part of a mixer simple element identifier. More...
 
unsigned int snd_mixer_selem_id_get_index (const snd_mixer_selem_id_t *obj)
 Get index part of a mixer simple element identifier. More...
 
void snd_mixer_selem_id_set_name (snd_mixer_selem_id_t *obj, const char *val)
 Set name part of a mixer simple element identifier. More...
 
void snd_mixer_selem_id_set_index (snd_mixer_selem_id_t *obj, unsigned int val)
 Set index part of a mixer simple element identifier. More...
 

Detailed Description

The simple mixer interface.

Macro Definition Documentation

#define snd_mixer_selem_id_alloca (   ptr)

allocate an invalid snd_mixer_selem_id_t using standard alloca

Parameters
ptrreturned pointer

Typedef Documentation

typedef struct _snd_mixer_selem_id snd_mixer_selem_id_t

Mixer simple element identifier

Enumeration Type Documentation

Mixer simple element channel identifier

Enumerator
SND_MIXER_SCHN_UNKNOWN 

Unknown

SND_MIXER_SCHN_FRONT_LEFT 

Front left

SND_MIXER_SCHN_FRONT_RIGHT 

Front right

SND_MIXER_SCHN_REAR_LEFT 

Rear left

SND_MIXER_SCHN_REAR_RIGHT 

Rear right

SND_MIXER_SCHN_FRONT_CENTER 

Front center

SND_MIXER_SCHN_WOOFER 

Woofer

SND_MIXER_SCHN_SIDE_LEFT 

Side Left

SND_MIXER_SCHN_SIDE_RIGHT 

Side Right

SND_MIXER_SCHN_REAR_CENTER 

Rear Center

SND_MIXER_SCHN_MONO 

Mono (Front left alias)

Mixer simple element - register options - abstraction level

Enumerator
SND_MIXER_SABSTRACT_NONE 

no abstraction - try use all universal controls from driver

SND_MIXER_SABSTRACT_BASIC 

basic abstraction - Master,PCM,CD,Aux,Record-Gain etc.

Function Documentation

snd_mixer_elem_t* snd_mixer_find_selem ( snd_mixer_t mixer,
const snd_mixer_selem_id_t id 
)

Find a mixer simple element.

Parameters
mixerMixer handle
idMixer simple element identifier
Returns
mixer simple element handle or NULL if not found
int snd_mixer_selem_ask_capture_dB_vol ( snd_mixer_elem_t elem,
long  dBvalue,
int  dir,
long *  value 
)

Return corresponding integer capture volume for given dB value for a mixer simple element.

Parameters
elemMixer simple element handle
dBvaluedB value to be converted to integer range
valuepointer to returned integer value
dirselect direction (-1 = accurate or first bellow, 0 = accurate, 1 = accurate or first above)
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_ask_capture_vol_dB ( snd_mixer_elem_t elem,
long  value,
long *  dBvalue 
)

Return corresponding dB value to an integer capture volume for a mixer simple element.

Parameters
elemMixer simple element handle
valuevalue to be converted to dB range
dBvaluepointer to returned dB value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_ask_playback_dB_vol ( snd_mixer_elem_t elem,
long  dBvalue,
int  dir,
long *  value 
)

Return corresponding integer playback volume for given dB value for a mixer simple element.

Parameters
elemMixer simple element handle
valuevalue to be converted to dB range
dirselect direction (-1 = accurate or first bellow, 0 = accurate, 1 = accurate or first above)
dBvaluepointer to returned dB value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_ask_playback_vol_dB ( snd_mixer_elem_t elem,
long  value,
long *  dBvalue 
)

Return corresponding dB value to an integer playback volume for a mixer simple element.

Parameters
elemMixer simple element handle
valuevalue to be converted to dB range
dBvaluepointer to returned dB value
Returns
0 on success otherwise a negative error code
const char* snd_mixer_selem_channel_name ( snd_mixer_selem_channel_id_t  channel)

Return name of mixer simple element channel.

Parameters
channelmixer simple element channel identifier
Returns
channel name
int snd_mixer_selem_get_capture_dB ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
long *  value 
)

Return value of capture volume in dB control of a mixer simple element.

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
valuepointer to returned value (dB * 100)
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_get_capture_dB_range ( snd_mixer_elem_t elem,
long *  min,
long *  max 
)

Get range in dB for capture volume of a mixer simple element.

Parameters
elemMixer simple element handle
minPointer to returned minimum (dB * 100)
maxPointer to returned maximum (dB * 100)
int snd_mixer_selem_get_capture_group ( snd_mixer_elem_t elem)

Return info about capture switch control of a mixer simple element.

Parameters
elemMixer simple element handle
Returns
group for switch exclusivity (see snd_mixer_selem_has_capture_switch_exclusive)
int snd_mixer_selem_get_capture_switch ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
int *  value 
)

Return value of capture switch control of a mixer simple element.

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
valuepointer to returned value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_get_capture_volume ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
long *  value 
)

Return value of capture volume control of a mixer simple element.

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
valuepointer to returned value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_get_capture_volume_range ( snd_mixer_elem_t elem,
long *  min,
long *  max 
)

Get range for capture volume of a mixer simple element.

Parameters
elemMixer simple element handle
minPointer to returned minimum
maxPointer to returned maximum
int snd_mixer_selem_get_enum_item ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
unsigned int *  itemp 
)

get the current selected enumerated item for the given mixer simple element

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
itempthe pointer to store the index of the enumerated item
Returns
0 if successful, otherwise a negative error code
int snd_mixer_selem_get_enum_item_name ( snd_mixer_elem_t elem,
unsigned int  item,
size_t  maxlen,
char *  buf 
)

get the enumerated item string for the given mixer simple element

Parameters
elemMixer simple element handle
itemthe index of the enumerated item to query
maxlenthe maximal length to be stored
bufthe buffer to store the name string
Returns
0 if successful, otherwise a negative error code
int snd_mixer_selem_get_enum_items ( snd_mixer_elem_t elem)

Return the number of enumerated items of the given mixer simple element.

Parameters
elemMixer simple element handle
Returns
the number of enumerated items, otherwise a negative error code
void snd_mixer_selem_get_id ( snd_mixer_elem_t elem,
snd_mixer_selem_id_t id 
)

Get mixer simple element identifier.

Parameters
elemMixer simple element handle
idreturned mixer simple element identifier
unsigned int snd_mixer_selem_get_index ( snd_mixer_elem_t elem)

Get index part of mixer simple element identifier.

Parameters
elemMixer simple element handle
Returns
index part of simple element identifier
const char* snd_mixer_selem_get_name ( snd_mixer_elem_t elem)

Get name part of mixer simple element identifier.

Parameters
elemMixer simple element handle
Returns
name part of simple element identifier
int snd_mixer_selem_get_playback_dB ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
long *  value 
)

Return value of playback volume in dB control of a mixer simple element.

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
valuepointer to returned value (dB * 100)
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_get_playback_dB_range ( snd_mixer_elem_t elem,
long *  min,
long *  max 
)

Get range in dB for playback volume of a mixer simple element.

Parameters
elemMixer simple element handle
minPointer to returned minimum (dB * 100)
maxPointer to returned maximum (dB * 100)
int snd_mixer_selem_get_playback_switch ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
int *  value 
)

Return value of playback switch control of a mixer simple element.

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
valuepointer to returned value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_get_playback_volume ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
long *  value 
)

Return value of playback volume control of a mixer simple element.

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
valuepointer to returned value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_get_playback_volume_range ( snd_mixer_elem_t elem,
long *  min,
long *  max 
)

Get range for playback volume of a mixer simple element.

Parameters
elemMixer simple element handle
minPointer to returned minimum
maxPointer to returned maximum
int snd_mixer_selem_has_capture_channel ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel 
)

Get info about channels of capture stream of a mixer simple element.

Parameters
elemMixer simple element handle
channelMixer simple element channel identifier
Returns
0 if channel is not present, 1 if present
int snd_mixer_selem_has_capture_switch ( snd_mixer_elem_t elem)

Return info about capture switch control existence of a mixer simple element.

Parameters
elemMixer simple element handle
Returns
0 if no control is present, 1 if it's present
int snd_mixer_selem_has_capture_switch_exclusive ( snd_mixer_elem_t elem)

Return info about capture switch control of a mixer simple element.

Parameters
elemMixer simple element handle
Returns
0 if control is separated per element, 1 if control acts on other elements too (i.e. only one active at a time inside a group)
int snd_mixer_selem_has_capture_switch_joined ( snd_mixer_elem_t elem)

Return info about capture switch control of a mixer simple element.

Parameters
elemMixer simple element handle
Returns
0 if control is separated per channel, 1 if control acts on all channels together
int snd_mixer_selem_has_capture_volume ( snd_mixer_elem_t elem)

Return info about capture volume control of a mixer simple element.

Parameters
elemMixer simple element handle
Returns
0 if no control is present, 1 if it's present
int snd_mixer_selem_has_capture_volume_joined ( snd_mixer_elem_t elem)

Return info about capture volume control of a mixer simple element.

Parameters
elemMixer simple element handle
Returns
0 if control is separated per channel, 1 if control acts on all channels together
int snd_mixer_selem_has_common_switch ( snd_mixer_elem_t elem)

Return true if mixer simple element has only one switch control for both playback and capture.

Parameters
elemMixer simple element handle
Returns
0 separated control, 1 common control
int snd_mixer_selem_has_common_volume ( snd_mixer_elem_t elem)

Return true if mixer simple element has only one volume control for both playback and capture.

Parameters
elemMixer simple element handle
Returns
0 separated control, 1 common control
int snd_mixer_selem_has_playback_channel ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel 
)

Get info about channels of playback stream of a mixer simple element.

Parameters
elemMixer simple element handle
channelMixer simple element channel identifier
Returns
0 if channel is not present, 1 if present
int snd_mixer_selem_has_playback_switch ( snd_mixer_elem_t elem)

Return info about playback switch control existence of a mixer simple element.

Parameters
elemMixer simple element handle
Returns
0 if no control is present, 1 if it's present
int snd_mixer_selem_has_playback_switch_joined ( snd_mixer_elem_t elem)

Return info about playback switch control of a mixer simple element.

Parameters
elemMixer simple element handle
Returns
0 if control is separated per channel, 1 if control acts on all channels together
int snd_mixer_selem_has_playback_volume ( snd_mixer_elem_t elem)

Return info about playback volume control of a mixer simple element.

Parameters
elemMixer simple element handle
Returns
0 if no control is present, 1 if it's present
int snd_mixer_selem_has_playback_volume_joined ( snd_mixer_elem_t elem)

Return info about playback volume control of a mixer simple element.

Parameters
elemMixer simple element handle
Returns
0 if control is separated per channel, 1 if control acts on all channels together
void snd_mixer_selem_id_copy ( snd_mixer_selem_id_t dst,
const snd_mixer_selem_id_t src 
)

copy one snd_mixer_selem_id_t to another

Parameters
dstpointer to destination
srcpointer to source
void snd_mixer_selem_id_free ( snd_mixer_selem_id_t obj)

frees a previously allocated snd_mixer_selem_id_t

Parameters
objpointer to object to free
unsigned int snd_mixer_selem_id_get_index ( const snd_mixer_selem_id_t obj)

Get index part of a mixer simple element identifier.

Parameters
objMixer simple element identifier
Returns
index part
const char* snd_mixer_selem_id_get_name ( const snd_mixer_selem_id_t obj)

Get name part of a mixer simple element identifier.

Parameters
objMixer simple element identifier
Returns
name part
int snd_mixer_selem_id_malloc ( snd_mixer_selem_id_t **  ptr)

allocate an invalid snd_mixer_selem_id_t using standard malloc

Parameters
ptrreturned pointer
Returns
0 on success otherwise negative error code
void snd_mixer_selem_id_set_index ( snd_mixer_selem_id_t obj,
unsigned int  val 
)

Set index part of a mixer simple element identifier.

Parameters
objMixer simple element identifier
valindex part
void snd_mixer_selem_id_set_name ( snd_mixer_selem_id_t obj,
const char *  val 
)

Set name part of a mixer simple element identifier.

Parameters
objMixer simple element identifier
valname part
size_t snd_mixer_selem_id_sizeof ( void  )

get size of snd_mixer_selem_id_t

Returns
size in bytes
int snd_mixer_selem_is_active ( snd_mixer_elem_t elem)

Get info about the active state of a mixer simple element.

Parameters
elemMixer simple element handle
Returns
0 if not active, 1 if active
int snd_mixer_selem_is_capture_mono ( snd_mixer_elem_t elem)

Get info about channels of capture stream of a mixer simple element.

Parameters
elemMixer simple element handle
Returns
0 if not mono, 1 if mono
int snd_mixer_selem_is_enum_capture ( snd_mixer_elem_t elem)

Return true if mixer simple enumerated element belongs to the capture direction.

Parameters
elemMixer simple element handle
Returns
0 no capture direction, 1 capture direction
int snd_mixer_selem_is_enum_playback ( snd_mixer_elem_t elem)

Return true if mixer simple enumerated element belongs to the playback direction.

Parameters
elemMixer simple element handle
Returns
0 no playback direction, 1 playback direction
int snd_mixer_selem_is_enumerated ( snd_mixer_elem_t elem)

Return true if mixer simple element is an enumerated control.

Parameters
elemMixer simple element handle
Returns
0 normal volume/switch control, 1 enumerated control
int snd_mixer_selem_is_playback_mono ( snd_mixer_elem_t elem)

Get info about channels of playback stream of a mixer simple element.

Parameters
elemMixer simple element handle
Returns
0 if not mono, 1 if mono
int snd_mixer_selem_register ( snd_mixer_t mixer,
struct snd_mixer_selem_regopt options,
snd_mixer_class_t **  classp 
)

Register mixer simple element class.

Parameters
mixerMixer handle
optionsOptions container
classpPointer to returned mixer simple element class handle (or NULL)
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_set_capture_dB ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
long  value,
int  dir 
)

Set value in dB of capture volume control of a mixer simple element.

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
valuecontrol value in dB * 100
dirselect direction (-1 = accurate or first bellow, 0 = accurate, 1 = accurate or first above)
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_set_capture_dB_all ( snd_mixer_elem_t elem,
long  value,
int  dir 
)

Set value in dB of capture volume control for all channels of a mixer simple element.

Parameters
elemMixer simple element handle
valuecontrol value in dB * 100
dirselect direction (-1 = accurate or first bellow, 0 = accurate, 1 = accurate or first above)
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_set_capture_switch ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
int  value 
)

Set value of capture switch control of a mixer simple element.

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
valuecontrol value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_set_capture_switch_all ( snd_mixer_elem_t elem,
int  value 
)

Set value of capture switch control for all channels of a mixer simple element.

Parameters
elemMixer simple element handle
valuecontrol value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_set_capture_volume ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
long  value 
)

Set value of capture volume control of a mixer simple element.

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
valuecontrol value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_set_capture_volume_all ( snd_mixer_elem_t elem,
long  value 
)

Set value of capture volume control for all channels of a mixer simple element.

Parameters
elemMixer simple element handle
valuecontrol value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_set_capture_volume_range ( snd_mixer_elem_t elem,
long  min,
long  max 
)

Set range for capture volume of a mixer simple element.

Parameters
elemMixer simple element handle
minminimum volume value
maxmaximum volume value
int snd_mixer_selem_set_enum_item ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
unsigned int  item 
)

set the current selected enumerated item for the given mixer simple element

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
itemthe enumerated item index
Returns
0 if successful, otherwise a negative error code
int snd_mixer_selem_set_playback_dB ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
long  value,
int  dir 
)

Set value in dB of playback volume control of a mixer simple element.

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
valuecontrol value in dB * 100
dirselect direction (-1 = accurate or first bellow, 0 = accurate, 1 = accurate or first above)
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_set_playback_dB_all ( snd_mixer_elem_t elem,
long  value,
int  dir 
)

Set value in dB of playback volume control for all channels of a mixer simple element.

Parameters
elemMixer simple element handle
valuecontrol value in dB * 100
dirselect direction (-1 = accurate or first bellow, 0 = accurate, 1 = accurate or first above)
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_set_playback_switch ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
int  value 
)

Set value of playback switch control of a mixer simple element.

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
valuecontrol value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_set_playback_switch_all ( snd_mixer_elem_t elem,
int  value 
)

Set value of playback switch control for all channels of a mixer simple element.

Parameters
elemMixer simple element handle
valuecontrol value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_set_playback_volume ( snd_mixer_elem_t elem,
snd_mixer_selem_channel_id_t  channel,
long  value 
)

Set value of playback volume control of a mixer simple element.

Parameters
elemMixer simple element handle
channelmixer simple element channel identifier
valuecontrol value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_set_playback_volume_all ( snd_mixer_elem_t elem,
long  value 
)

Set value of playback volume control for all channels of a mixer simple element.

Parameters
elemMixer simple element handle
valuecontrol value
Returns
0 on success otherwise a negative error code
int snd_mixer_selem_set_playback_volume_range ( snd_mixer_elem_t elem,
long  min,
long  max 
)

Set range for playback volume of a mixer simple element.

Parameters
elemMixer simple element handle
minminimum volume value
maxmaximum volume value

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