diff --git a/dlls/setupapi/devinst.c b/dlls/setupapi/devinst.c
index 4b25529b4f3..d6b37fad0fa 100644
--- a/dlls/setupapi/devinst.c
+++ b/dlls/setupapi/devinst.c
@@ -1123,3 +1123,31 @@ HKEY WINAPI SetupDiOpenClassRegKeyExW(
 
     return hClassKey;
 }
+
+/***********************************************************************
+ *		SetupDiOpenDeviceInterfaceA (SETUPAPI.@)
+ */
+BOOL WINAPI SetupDiOpenDeviceInterfaceW(
+       HDEVINFO DeviceInfoSet,
+       PCWSTR DevicePath,
+       DWORD OpenFlags,
+       PSP_DEVICE_INTERFACE_DATA DeviceInterfaceData)
+{
+    FIXME("%p %s %08lx %p\n",
+        DeviceInfoSet, debugstr_w(DevicePath), OpenFlags, DeviceInterfaceData);
+    return FALSE;
+}
+
+/***********************************************************************
+ *		SetupDiOpenDeviceInterfaceA (SETUPAPI.@)
+ */
+BOOL WINAPI SetupDiOpenDeviceInterfaceA(
+       HDEVINFO DeviceInfoSet,
+       PCSTR DevicePath,
+       DWORD OpenFlags,
+       PSP_DEVICE_INTERFACE_DATA DeviceInterfaceData)
+{
+    FIXME("%p %s %08lx %p\n", DeviceInfoSet,
+        debugstr_a(DevicePath), OpenFlags, DeviceInterfaceData);
+    return FALSE;
+}
diff --git a/dlls/setupapi/setupapi.spec b/dlls/setupapi/setupapi.spec
index 98dd31a3c1a..204001f98ab 100644
--- a/dlls/setupapi/setupapi.spec
+++ b/dlls/setupapi/setupapi.spec
@@ -359,9 +359,9 @@
 @ stub SetupDiOpenDevRegKey
 @ stub SetupDiOpenDeviceInfoA
 @ stub SetupDiOpenDeviceInfoW
-@ stub SetupDiOpenDeviceInterfaceA
+@ stdcall SetupDiOpenDeviceInterfaceA(ptr str long ptr)
 @ stub SetupDiOpenDeviceInterfaceRegKey
-@ stub SetupDiOpenDeviceInterfaceW
+@ stdcall SetupDiOpenDeviceInterfaceW(ptr wstr long ptr)
 @ stub SetupDiRegisterDeviceInfo
 @ stub SetupDiRemoveDevice
 @ stub SetupDiRemoveDeviceInterface