Драйвер ACPI

NTSTATUS
SendDownStreamIrp(
    IN PDEVICE_OBJECT   Pdo,
    IN ULONG            Ioctl,
    IN PVOID            InputBuffer,
    IN ULONG            InputSize,
    IN PVOID            OutputBuffer,
    IN ULONG            OutputSize
)

{
    IO_STATUS_BLOCK     ioBlock;
    KEVENT                    myIoctlEvent;
    NTSTATUS                status;
    PIRP                         irp;

    // Initialize an event to wait on
    KeInitializeEvent(&myIoctlEvent, SynchronizationEvent, FALSE);

    // Build the request
    irp = IoBuildDeviceIoControlRequest(
        Ioctl,
        Pdo,
        InputBuffer,
        InputSize,
        OutputBuffer,
        OutputSize,
        FALSE,
        &myIoctlEvent,
        &ioBlock);

    if (!irp) {
        return STATUS_INSUFFICIENT_RESOURCES;
    }

   
    // Pass request to Pdo, always wait for completion routine
    status = IoCallDriver(Pdo, irp);

    if (status == STATUS_PENDING) {
       
        // Wait for the IRP to be completed, then grab the real status code
        KeWaitForSingleObject(
            &myIoctlEvent,
            Executive,
            KernelMode,
            FALSE,
            NULL);

        status = ioBlock.Status;
    }
   

    return status;
}

PACPI_METHOD_ARGUMENT  argument;
ACPI_EVAL_INPUT_BUFFER InputBuffer;
ACPI_EVAL_OUTPUT_BUFFER OutputBuffer;
RtlZeroMemory( &InputBuffer, sizeof(ACPI_EVAL_INPUT_BUFFER) );
RtlZeroMemory( &OutputBuffer, sizeof(ACPI_EVAL_OUTPUT_BUFFER) );
InputBuffer.MethodNameAsUlong = ACPI_METHOD__TMP;
InputBuffer.Signature = ACPI_EVAL_INPUT_BUFFER_SIGNATURE;
status = SendDownStreamIrp(
                dx->pLowerDevice,
                IOCTL_ACPI_EVAL_METHOD,
                &InputBuffer,
                sizeof(ACPI_EVAL_INPUT_BUFFER),
                &OutputBuffer,
                sizeof(ACPI_EVAL_OUTPUT_BUFFER)
);
       
//
// if not successful, the control method probably does not  
// exists or APM mode is being used
//  
if( NT_SUCCESS( status))
{
   
    // Sanity check the data
    if ((OutputBuffer.Signature != _EVAL_OUTPUT_BUFFER_SIGNATURE) || (OutputBuffer.Count == 0)) {
        status = STATUS_ACPI_INVALID_DATA;
    }
    else
    {
        // Grab the argument
        argument = OutputBuffer.Argument;
   
        //
        // make sure we received the correct data type back
        //
        ........
    }
}