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WDF_POWER_POLICY_IDLE_TIMEOUT_TYPE enumeration (wdfdevice.h)

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[Applies to KMDF and UMDF]

The WDF_POWER_POLICY_IDLE_TIMEOUT_TYPE enumeration identifies how the idle timeout for a device is determined.

Syntax

typedef enum _WDF_POWER_POLICY_IDLE_TIMEOUT_TYPE {
  DriverManagedIdleTimeout = 0,
  SystemManagedIdleTimeout = 1,
  SystemManagedIdleTimeoutWithHint = 2
} WDF_POWER_POLICY_IDLE_TIMEOUT_TYPE, *PWDF_POWER_POLICY_IDLE_TIMEOUT_TYPE;

Constants

 
DriverManagedIdleTimeout
Value: 0
The idle timeout value is determined by the IdleTimeout member of the WDF_DEVICE_POWER_POLICY_IDLE_SETTINGS structure.
SystemManagedIdleTimeout
Value: 1
Starting in Windows 8, the timeout value is determined by the power framework (PoFx). The value of the IdleTimeout member is not used.

On operating systems earlier than Windows 8, the behavior is same as DriverManagedIdleTimeout.
SystemManagedIdleTimeoutWithHint
Value: 2
Starting in Windows 8, the PoFx uses the value specified in the IdleTimeout member as an input when determining at what point after all the components are idle to transition the device to a low-power (Dx) state. This option enables the driver to delay the transition to a low-power state.

The actual duration after which the PoFx allows the device to enter a low-power state might be greater than the IdleTimeout value.

On operating systems earlier than Windows 8, the behavior is the same as DriverManagedIdleTimeout.

Remarks

The WDF_POWER_POLICY_IDLE_TIMEOUT_TYPE enumeration is used in the WDF_DEVICE_POWER_POLICY_IDLE_SETTINGS structure.

Requirements

Requirement Value
Minimum KMDF version 1.11
Minimum UMDF version 2.0
Header wdfdevice.h (include Wdf.h)

See also

WDF_DEVICE_POWER_POLICY_IDLE_SETTINGS