Description
Add a Feature Unit to the specified class instance (i.e. audio function).
Files
usbd_audio.h / usbd_audio.c
Prototype
Arguments
class_nbr
Class instance number.
p_fu_cfg
Pointer to the Feature Unit configuration structure.
p_fu_api
Pointer to the audio codec API associated to this Feature Unit.
p_err
Pointer to variable that will receive the return error code from this function.
USBD_ERR_NONE
USBD_ERR_CLASS_INVALID_NBR
USBD_ERR_NULL_PTR
USBD_ERR_AUDIO_FU_ALLOC
Returned Value
Unit ID assigned by audio class, if NO error(s).
0, otherwise
Callers
Application.
Notes / Warnings
Audio 1.0 specification indicates that ID #0 is reserved for undefined ID. Thus it indicates an error.
p_fu_api
can NOT beDEF_NULL
. A Feature Unit must at least support the mute and volume controls.