StorPortPoFxPowerControl function (storport.h)
The StorPortPoFxPowerControl routine sends a power control request to the power management framework (PoFx) to forward to the power engine plug-in (PEP).
Syntax
ULONG StorPortPoFxPowerControl(
[in] PVOID HwDeviceExtension,
PSTOR_ADDRESS Address,
[in] LPCGUID PowerControlCode,
[in, optional] PVOID InBuffer,
[in] SIZE_T InBufferSize,
[out, optional] PVOID OutBuffer,
[in] SIZE_T OutBufferSize,
[out, optional] PSIZE_T BytesReturned
);
Parameters
[in] HwDeviceExtension
A pointer to the hardware device extension for the host bus adapter (HBA). This is the device extension used to register the device in a prior call to StorPortInitializePoFxPower.
Address
A pointer to the power control code. This code is a GUID value that specifies the requested operation.
[in] PowerControlCode
A pointer to the power control code. This code is a GUID value that specifies the requested operation.
[in, optional] InBuffer
A pointer to a caller-allocated buffer that contains the input data for the operation. The format for the data in this buffer depends on the power control code specified by the PowerControlCode parameter. The InBuffer parameter is optional and can be specified as NULL if the specified operation requires no input data.
[in] InBufferSize
The size, in bytes, of the input buffer that is pointed to by the InBuffer parameter. If InBuffer is NULL, set InBufferSize to zero.
[out, optional] OutBuffer
A pointer to a caller-allocated buffer that is to contain the output data from the operation. The format for the data in this buffer depends on the power control code specified by the PowerControlCode parameter. The OutBuffer parameter is optional and can be specified as NULL if the specified operation produces no output data.
[in] OutBufferSize
The size, in bytes, of the output buffer that is pointed to by the OutBuffer parameter. If OutBuffer is NULL, set OutBufferSize to zero.
[out, optional] BytesReturned
A pointer to a location into which the routine writes the number of bytes of data that were written to the buffer that is pointed to by OutBuffer. The number of bytes written will be less than or equal to OutBufferSize. This parameter is optional and can be specified as NULL if the caller does not need to know how many bytes were written to the output buffer.
Return value
The StorPortPoFxPowerControl routine returns one of these status codes:
| Return code | Description |
|---|---|
|
The power control operation specified in PowerControlCode was successfully executed. |
|
Either HwDeviceExtension or Device is NULL.
-or- Address points to an invalid unit address structure. -or- The storage device specified by Address is not found. |
|
The storage device is not registered with the PoFx. |
|
The current IRQL > DISPATCH_LEVEL. |
|
The power control operation was unsuccessful. |
Remarks
A miniport driver calls this routine to send a power control request directly to the PEP. A power control request is similar to an I/O control request (IOCTL). Unlike an IOCTL, however, a power control request is sent directly to PEP and is not observed by other device drivers in the device stack. During a StorPortPoFxPowerControl call, the PEP synchronously performs the requested operation.
Similarly, The PEP can send a power control request directly to the miniport. The miniport driver handles this request in its HwStorAdapterControl and HwStorUnitControl routines. The ControlType parameter receives the ScsiAdapterPoFxPowerControl type in the HwStorAdapterControl routine and the ScsiUnitPoFxPowerControl in the HwStorUnitControl routine.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Available in starting with Windows 8. |
| Target Platform | Universal |
| Header | storport.h |
| Library | Storport.lib |
| IRQL | <= DISPATCH_LEVEL |