diff --git a/dlls/ntoskrnl.exe/ntoskrnl.c b/dlls/ntoskrnl.exe/ntoskrnl.c
index 18317e206ca..d2c03404440 100644
--- a/dlls/ntoskrnl.exe/ntoskrnl.c
+++ b/dlls/ntoskrnl.exe/ntoskrnl.c
@@ -1540,6 +1540,15 @@ VOID WINAPI READ_REGISTER_BUFFER_UCHAR(PUCHAR Register, PUCHAR Buffer, ULONG Cou
     FIXME("stub\n");
 }
 
+/*****************************************************
+ *           PoSetPowerState   (NTOSKRNL.EXE.@)
+ */
+POWER_STATE WINAPI PoSetPowerState(PDEVICE_OBJECT DeviceObject, POWER_STATE_TYPE Type, POWER_STATE State)
+{
+    FIXME("(%p %u %u) stub\n", DeviceObject, Type, State.DeviceState);
+    return State;
+}
+
 /*****************************************************
  *           DllMain
  */
diff --git a/dlls/ntoskrnl.exe/ntoskrnl.exe.spec b/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
index 74c53e9a003..06976fdc65c 100644
--- a/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
+++ b/dlls/ntoskrnl.exe/ntoskrnl.exe.spec
@@ -830,7 +830,7 @@
 @ stub PoRequestPowerIrp
 @ stub PoRequestShutdownEvent
 @ stub PoSetHiberRange
-@ stub PoSetPowerState
+@ stdcall PoSetPowerState(ptr long long)
 @ stub PoSetSystemState
 @ stub PoShutdownBugCheck
 @ stub PoStartNextPowerIrp
diff --git a/include/ddk/wdm.h b/include/ddk/wdm.h
index 3fa355f8230..950d93a6536 100644
--- a/include/ddk/wdm.h
+++ b/include/ddk/wdm.h
@@ -1129,6 +1129,7 @@ MM_SYSTEMSIZE WINAPI MmQuerySystemSize(void);
 
 NTSTATUS  WINAPI ObReferenceObjectByHandle(HANDLE,ACCESS_MASK,POBJECT_TYPE,KPROCESSOR_MODE,PVOID*,POBJECT_HANDLE_INFORMATION);
 
+POWER_STATE WINAPI PoSetPowerState(PDEVICE_OBJECT,POWER_STATE_TYPE,POWER_STATE);
 NTSTATUS  WINAPI PsCreateSystemThread(PHANDLE,ULONG,POBJECT_ATTRIBUTES,HANDLE,PCLIENT_ID,PKSTART_ROUTINE,PVOID);
 #define          PsGetCurrentProcess() IoGetCurrentProcess()
 #define          PsGetCurrentThread() ((PETHREAD)KeGetCurrentThread())