Type Alias usbd_callback 

pub type usbd_callback = Option<unsafe extern "C" fn(arg1: usbd_xfer_handle, arg2: usbd_private_handle, arg3: usbd_status)>;

Aliased Type

pub enum usbd_callback {
    None,
    Some(unsafe extern "C" fn(*mut usbd_xfer, *mut c_void, u32)),
}

Variants

None

No value.

Some(unsafe extern "C" fn(*mut usbd_xfer, *mut c_void, u32))

Some value of type T.