diff --git a/src/lib.rs b/src/lib.rs
index d253c37..c1f364c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -130,11 +130,15 @@ impl TwoWirePort {
             mvpdfreq: nvme::mi::SmbusFrequency::FreqNotSupported,
             cmeaddr: 0x1d,
             i3csprt: false,
-            msmbfreq: nvme::mi::SmbusFrequency::Freq400Khz,
+            msmbfreq: nvme::mi::SmbusFrequency::Freq100Khz,
             nvmebms: false,
             smbfreq: nvme::mi::SmbusFrequency::Freq100Khz,
         }
     }
+
+    pub fn builder() -> TwoWirePortBuilder {
+        Default::default()
+    }
 }
 
 impl Default for TwoWirePort {
@@ -143,6 +147,36 @@ impl Default for TwoWirePort {
     }
 }
 
+pub struct TwoWirePortBuilder {
+    msmbfreq: nvme::mi::SmbusFrequency,
+}
+
+impl TwoWirePortBuilder {
+    pub fn new() -> Self {
+        Self {
+            msmbfreq: nvme::mi::SmbusFrequency::Freq100Khz,
+        }
+    }
+
+    pub fn msmbfreq(&mut self, freq: nvme::mi::SmbusFrequency) -> &mut Self {
+        self.msmbfreq = freq;
+        self
+    }
+
+    pub fn build(&self) -> TwoWirePort {
+        TwoWirePort {
+            msmbfreq: self.msmbfreq,
+            ..Default::default()
+        }
+    }
+}
+
+impl Default for TwoWirePortBuilder {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 #[derive(Debug, PartialEq, Eq)]
 #[repr(u8)]
 pub enum PortType {
diff --git a/tests/nvme_mi.rs b/tests/nvme_mi.rs
index 3ce4321..9ff8708 100644
--- a/tests/nvme_mi.rs
+++ b/tests/nvme_mi.rs
@@ -221,7 +221,13 @@ mod read_nvme_mi_data_structure {
     fn port_information_twowire() {
         setup();
 
-        let (mut mep, mut subsys) = new_device(DeviceType::P1p1tC1iN0a0a);
+        let mut subsys = Subsystem::new(SubsystemInfo::invalid());
+        let _ = subsys.add_port(PortType::Pcie(PciePort::new())).unwrap();
+        let twp = TwoWirePort::builder()
+            .msmbfreq(nvme_mi_dev::nvme::mi::SmbusFrequency::Freq400Khz)
+            .build();
+        let twpid = subsys.add_port(PortType::TwoWire(twp)).unwrap();
+        let mut mep = ManagementEndpoint::new(twpid);
 
         #[rustfmt::skip]
         const REQ: [u8; 19] = [
@@ -1272,7 +1278,13 @@ mod configuration_set {
     fn smbus_i2c_frequency_supported() {
         setup();
 
-        let (mut mep, mut subsys) = new_device(DeviceType::P1p1tC1iN0a0a);
+        let mut subsys = Subsystem::new(SubsystemInfo::invalid());
+        let _ = subsys.add_port(PortType::Pcie(PciePort::new())).unwrap();
+        let twp = TwoWirePort::builder()
+            .msmbfreq(nvme_mi_dev::nvme::mi::SmbusFrequency::Freq400Khz)
+            .build();
+        let twpid = subsys.add_port(PortType::TwoWire(twp)).unwrap();
+        let mut mep = ManagementEndpoint::new(twpid);
 
         #[rustfmt::skip]
         const REQ_GET_INIT: [u8; 19] = [