IPowerPolicyCallbackWakeFromSx interface

[Warning: UMDF 2 is the latest version of UMDF and supersedes UMDF 1. All new UMDF drivers should be written using UMDF 2. No new features are being added to UMDF 1 and there is limited support for UMDF 1 on newer versions of Windows 10. Universal Windows drivers must use UMDF 2. For more info, see Getting Started with UMDF.]

A driver's IPowerPolicyCallbackWakeFromSx interface provides callback functions that the framework calls to notify the driver about wake events. These events are related to a device's ability to wake both itself and the system from a low-power state.


The IPowerPolicyCallbackWakeFromSx interface inherits from the IUnknown interface. IPowerPolicyCallbackWakeFromSx also has these types of members:


The IPowerPolicyCallbackWakeFromSx interface has these methods.


A driver's OnArmWakeFromSx event callback function arms (that is, enables) a device so that it can trigger a wake signal while in a low-power device state. The wake signal causes the device to enter its working state (D0) and the system to enter its working state (S0).


A driver's OnDisarmWakeFromSx event callback function disarms (that is, disables) a device's ability to trigger a wake signal while the device and system are in low-power states.


A driver's OnWakeFromSxTriggered event callback function informs the driver that its device, which had previously entered a low-power device state because system power was reduced, might have triggered a wake signal.



If your driver supports an IPowerPolicyCallbackWakeFromSx interface for a device, the IUnknown::QueryInterface method that the driver passes to IWDFDriver::CreateDevice must return the interface.


Target platform


End of support

Unavailable in UMDF 2.0 and later.

Minimum UMDF version



Wudfddi.h (include Wudfddi.h)



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