if (i == ARRAY_SIZE(snd_motu_clock_rates))
                return -EINVAL;
 
-       pcm_chunks = formats->fixed_part_pcm_chunks[mode] +
-                    formats->differed_part_pcm_chunks[mode];
+       // Each data block includes SPH in its head. Data chunks follow with
+       // 3 byte alignment. Padding follows with zero to conform to quadlet
+       // alignment.
+       pcm_chunks = formats->pcm_chunks[mode];
        data_chunks = formats->msg_chunks + pcm_chunks;
-
-       /*
-        * Each data block includes SPH in its head. Data chunks follow with
-        * 3 byte alignment. Padding follows with zero to conform to quadlet
-        * alignment.
-        */
        data_block_quadlets = 1 + DIV_ROUND_UP(data_chunks * 3, 4);
 
        err = amdtp_stream_set_parameters(s, rate, data_block_quadlets);
 
        data &= ~(TX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS |
                  RX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS|
                  TX_PACKET_TRANSMISSION_SPEED_MASK);
-       if (motu->tx_packet_formats.differed_part_pcm_chunks[0] == 0)
+       if (motu->spec->tx_fixed_pcm_chunks[0] == motu->tx_packet_formats.pcm_chunks[0])
                data |= TX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS;
-       if (motu->rx_packet_formats.differed_part_pcm_chunks[0] == 0)
+       if (motu->spec->rx_fixed_pcm_chunks[0] == motu->rx_packet_formats.pcm_chunks[0])
                data |= RX_PACKET_EXCLUDE_DIFFERED_DATA_CHUNKS;
        data |= fw_parent_device(motu->unit)->max_speed;