mcspi_wait_for_completion
ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);