[Applies to KMDF and UMDF]

A driver's EvtDeviceDisarmWakeFromS0 event callback function disarms (that is, disables) a device's ability to trigger a wake signal while in a low-power device state, if the system remains in the system working state (S0).



void EvtWdfDeviceDisarmWakeFromS0(



A handle to a framework device object.

Return Value



To register an EvtDeviceDisarmWakeFromS0 callback function, a driver must call WdfDeviceInitSetPowerPolicyEventCallbacks. The driver must also set IdleCanWakeFromS0 in the IdleCaps member of its WDF_DEVICE_POWER_POLICY_IDLE_SETTINGS structure.

If the driver has registered an EvtDeviceDisarmWakeFromS0 callback function, the framework calls it after the bus driver determines that an event has awakened the device, and after the bus driver subsequently completes the wait/wake IRP. Before calling the driver's EvtDeviceDisarmWakeFromS0EvtDeviceDisarmWakeFromS0 callback function, the framework calls the driver's EvtDeviceD0Entry, EvtInterruptEnable, and EvtDeviceWakeFromS0Triggered callback functions.

The EvtDeviceDisarmWakeFromS0 callback function must perform any hardware operations that are needed to disable the device's ability to trigger a wake signal after the power has been lowered.

For more information about when the framework calls this callback function, see PnP and Power Management Scenarios.

For more information about this callback function, see Supporting Idle Power-Down.

The EvtDeviceDisarmWakeFromS0 callback function is called at IRQL = PASSIVE_LEVEL. You should not make this callback function pageable.


To define an EvtDeviceDisarmWakeFromS0 callback function, you must first provide a function declaration that identifies the type of callback function you’re defining. Windows provides a set of callback function types for drivers. Declaring a function using the callback function types helps Code Analysis for Drivers, Static Driver Verifier (SDV), and other verification tools find errors, and it’s a requirement for writing drivers for the Windows operating system.

For example, to define an EvtDeviceDisarmWakeFromS0 callback function that is named MyDeviceDisarmWakeFromS0, use the EVT_WDF_DEVICE_DISARM_WAKE_FROM_S0 type as shown in this code example:


Then, implement your callback function as follows:

 MyDeviceDisarmWakeFromS0 (
    WDFDEVICE  Device

The EVT_WDF_DEVICE_DISARM_WAKE_FROM_S0 function type is defined in the Wdfdevice.h header file. To more accurately identify errors when you run the code analysis tools, be sure to add the Use_decl_annotations annotation to your function definition. The Use_decl_annotations annotation ensures that the annotations that are applied to the EVT_WDF_DEVICE_DISARM_WAKE_FROM_S0 function type in the header file are used. For more information about the requirements for function declarations, see Declaring Functions by Using Function Role Types for KMDF Drivers. For information about Use_decl_annotations, see Annotating Function Behavior.


Target Platform Universal
Minimum KMDF version 1.0
Minimum UMDF version 2.0
Header wdfdevice.h (include Wdf.h)
IRQL PASSIVE_LEVEL (see Remarks section)

See Also



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