43.6.8 DMA Controller Operation
All receiver audio channels are assigned to a single DMA Controller.
The DMA Controller reads from the I2SC_RHR and writes to the I2SC_THR for both audio channels successively.
The DMA Controller transfers may use 32-bit word, 16-bit halfword, or 8-bit byte depending on the value of the I2SC_MR.DATALENGTH field.