OHCI1394_AT_DATA_Q0_tCode_MASK
return (le32_to_cpu(data[0]) & OHCI1394_AT_DATA_Q0_tCode_MASK) >> OHCI1394_AT_DATA_Q0_tCode_SHIFT;
data[0] &= cpu_to_le32(~OHCI1394_AT_DATA_Q0_tCode_MASK);
data[0] |= cpu_to_le32((tcode << OHCI1394_AT_DATA_Q0_tCode_SHIFT) & OHCI1394_AT_DATA_Q0_tCode_MASK);