WDF_STATE_NOTIFICATION_TYPE enumeration
[Applies to KMDF only]
The WDF_STATE_NOTIFICATION_TYPE enumeration identifies the type of Plug and Play, power, or power policy notification that a framework-based driver will receive.
Syntax
typedef enum _WDF_STATE_NOTIFICATION_TYPE { StateNotificationInvalid = 0x0000, StateNotificationEnterState = 0x0001, StateNotificationPostProcessState = 0x0002, StateNotificationLeaveState = 0x0004, StateNotificationAllStates = StateNotificationEnterState | StateNotificationPostProcessState | StateNotificationLeaveState } WDF_STATE_NOTIFICATION_TYPE;
Constants
- StateNotificationInvalid
-
For internal use only.
- StateNotificationEnterState
-
The driver is notified immediately before a device's Plug and Play, power, or power policy state machine enters a specified state.
- StateNotificationPostProcessState
-
The driver is notified immediately after a device's Plug and Play, power, or power policy state machine enters a specified state.
- StateNotificationLeaveState
-
The driver is notified immediately before a device's Plug and Play, power, or power policy state machine leaves a specified state.
- StateNotificationAllStates
-
The driver receives enter-state, postprocess-state, and leave-state notifications.
Remarks
When the framework's state machine for a driver's device changes from state a to state b, the framework notifies the driver (if the driver registered an appropriate event callback function), in the following sequence:
-
Calls state a's leave-state notification callback function.
-
Calls state b's enter-state notification callback function.
-
Changes the device's state from a to b.
-
Calls state b's postprocess-state notification callback function.
To register for notification of a change in state, the driver can call the following methods:
Requirements
|
Minimum KMDF version | 1.0 |
|---|---|
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Header |
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See also
- WDF_DEVICE_PNP_NOTIFICATION_DATA
- WDF_DEVICE_POWER_NOTIFICATION_DATA
- WDF_DEVICE_POWER_POLICY_NOTIFICATION_DATA
