Function get_dma_stream_handle 

pub fn get_dma_stream_handle(stream: StreamLabel) -> Status

Get global identifier for a given DMA stream label

Usage

This syscall set the MA stream handle that matches the given label in the SVC_EXCHANGE area if the label matches a DMA stream that has been declared in the device tree and is owned by the current task.

If label is not found or no accessible shared memory is found, the resulting status is Status::Invalid. The SVC_EXCHANGE area is not set.

NOTE: except without good reasons, do not use this syscall directly

Example

match get_dma_stream_handle(streamlabel) {
   Status::Ok => (),
    any_err => return (any_err),
}
let exch_area = unsafe { &mut SVC_EXCHANGE_AREA[..4] };
let handle = u32::from_ne_bytes(exch_area.try_into().map_err(|_| Status::Invalid)?);