EVT_WDF_DEVICE_RELEASE_HARDWARE callback function (wdfdevice.h)
[Applies to KMDF and UMDF]
A driver's EvtDeviceReleaseHardware event callback function performs operations that are needed when a device is no longer accessible.
Syntax
EVT_WDF_DEVICE_RELEASE_HARDWARE EvtWdfDeviceReleaseHardware;
NTSTATUS EvtWdfDeviceReleaseHardware(
[in] WDFDEVICE Device,
[in] WDFCMRESLIST ResourcesTranslated
)
{...}
Parameters
[in] Device
A handle to a framework device object.
[in] ResourcesTranslated
A handle to a resource list object that identifies the translated hardware resources that the Plug and Play manager has assigned to the device.
Return value
If the EvtDeviceReleaseHardware callback function encounters no errors, it must return STATUS_SUCCESS or another status value for which NT_SUCCESS(status) equals TRUE. Otherwise, it must return a status value for which NT_SUCCESS(status) equals FALSE. Do not return STATUS_NOT_SUPPORTED.
Remarks
To register an EvtDeviceReleaseHardware callback function, your driver must call WdfDeviceInitSetPnpPowerEventCallbacks.
If a driver has registered an EvtDeviceReleaseHardware callback function, the framework calls it during the following transitions:
- Resource rebalancing
- Orderly removal
- Surprise removal
The framework calls the EvtDeviceReleaseHardware callback function after the framework has stopped sending I/O requests to the device, any interrupts assigned to the device have been disabled and disconnected, and the device has been turned off.
When the framework calls the EvtDeviceReleaseHardware, the PDO for the device still exists and can be queried for device information that is available in the powered off state, for example PCI configuration state.
In addition, the translated hardware resources that the framework supplies to EvtDeviceReleaseHardware are still assigned to the device. The primary purpose of this callback function is to release those resources, and in particular to unmap any memory resources that the driver's EvtDevicePrepareHardware callback function mapped. The driver can also use this callback to perform any other driver or device management activity that might be required in the powered down state. Usually, all other hardware shutdown operations should take place in the driver's EvtDeviceD0Exit callback function.
The framework always calls the driver's EvtDeviceReleaseHardware callback function if the driver's EvtDevicePrepareHardware callback function has been called, even if EvtDevicePrepareHardware returned a failure code.
A driver for a device that has child devices can control the order in which the framework calls the EvtDeviceReleaseHardware callback functions for the parent device and its children by calling WdfDeviceInitSetReleaseHardwareOrderOnFailure from within its EvtDriverDeviceAdd callback function.
For more information about when the framework calls this callback function, see PnP and Power Management Scenarios.
For more information about hardware resources, see Hardware Resources for Framework-Based Drivers.
For more information about drivers that provide this callback function, see Supporting PnP and Power Management in Function Drivers.
Requirements
| Requirement | Value |
|---|---|
| Target Platform | Universal |
| Minimum KMDF version | 1.0 |
| Minimum UMDF version | 2.0 |
| Header | wdfdevice.h (include Wdf.h) |
| IRQL | PASSIVE_LEVEL |