DP_IN_ADAPTER_INFO
dpcd_dp_tun_data[DP_IN_ADAPTER_INFO - DP_TUNNELING_CAPABILITIES_SUPPORT];
DPTUN_REG(DP_IN_ADAPTER_INFO) | \
tunnel->adapter_id = tunnel_reg(regs, DP_IN_ADAPTER_INFO) & DP_IN_ADAPTER_NUMBER_MASK;