intwmi.c

学习usb编程很好的例子 自己学习用的。

        so the irp should be completed with the buffer needed.        
            
    OutBufferSize has the maximum size available to write the data
        block.

    Buffer on return is filled with the returned data block


Return Value:

    status

--*/
{
    PDEVICE_EXTENSION deviceExtension;
    NTSTATUS          ntStatus;
    ULONG             size;
    WCHAR             modelName[] = L"Aishverya\0\0";
    USHORT            modelNameLen;

    PAGED_CODE();

    KdPrint( ("IntUsb_QueryWmiDataBlock - begins\n"));

    size = 0;
    modelNameLen = (wcslen(modelName) + 1) * sizeof(WCHAR);

    //
    // Only ever registers 1 instance per guid
    //

    ASSERT((InstanceIndex == 0) &&
           (InstanceCount == 1));
    
    deviceExtension = (PDEVICE_EXTENSION) DeviceObject->DeviceExtension;

    switch (GuidIndex) {

    case WMI_INTUSB_DRIVER_INFORMATION:

        size = sizeof(ULONG) + modelNameLen + sizeof(USHORT);

        if (OutBufferSize < size ) {

            KdPrint( ("OutBuffer too small\n"));

            ntStatus = STATUS_BUFFER_TOO_SMALL;

            break;
        }

        * (PULONG) Buffer = DebugLevel;

        Buffer += sizeof(ULONG);

        //
        // put length of string ahead of string
        //

        *((PUSHORT)Buffer) = modelNameLen;

        Buffer = (PUCHAR)Buffer + sizeof(USHORT);

        RtlCopyBytes((PVOID)Buffer, (PVOID)modelName, modelNameLen);

        *InstanceLengthArray = size ;

        ntStatus = STATUS_SUCCESS;

        break;

    default:

        ntStatus = STATUS_WMI_GUID_NOT_FOUND;
    }

    ntStatus = WmiCompleteRequest(DeviceObject,
                                Irp,
                                ntStatus,
                                size,
                                IO_NO_INCREMENT);

    KdPrint( ("IntUsb_QueryWmiDataBlock - ends\n"));

    return ntStatus;
}


NTSTATUS
IntUsb_SetWmiDataItem(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP           Irp,
    IN ULONG          GuidIndex,
    IN ULONG          InstanceIndex,
    IN ULONG          DataItemId,
    IN ULONG          BufferSize,
    IN PUCHAR         Buffer
    )
/*++

Routine Description:

    This routine is a callback into the driver to set for the contents of
    a data block. When the driver has finished filling the data block it
    must call WmiCompleteRequest to complete the irp. The driver can
    return STATUS_PENDING if the irp cannot be completed immediately.

Arguments:

    DeviceObject is the device whose data block is being queried

    Irp is the Irp that makes this request

    GuidIndex is the index into the list of guids provided when the
        device registered

    InstanceIndex is the index that denotes which instance of the data block
        is being queried.
            
    DataItemId has the id of the data item being set

    BufferSize has the size of the data item passed

    Buffer has the new values for the data item


Return Value:

    status

--*/
{
    PDEVICE_EXTENSION deviceExtension;
    NTSTATUS          ntStatus;
    ULONG             info;
    
    PAGED_CODE();

    KdPrint( ("IntUsb_SetWmiDataItem - begins\n"));

    deviceExtension = (PDEVICE_EXTENSION) DeviceObject->DeviceExtension;
    info = 0;

    switch(GuidIndex) {
    
    case WMI_INTUSB_DRIVER_INFORMATION:

        if(DataItemId == 1) {

            if(BufferSize == sizeof(ULONG)) {

                DebugLevel = *((PULONG)Buffer);

                ntStatus = STATUS_SUCCESS;

                info = sizeof(ULONG);
            }
            else {

                ntStatus = STATUS_INFO_LENGTH_MISMATCH;
            }
        }
        else {

            ntStatus = STATUS_WMI_READ_ONLY;
        }

        break;

    default:

        ntStatus = STATUS_WMI_GUID_NOT_FOUND;
    }

    ntStatus = WmiCompleteRequest(DeviceObject,
                                Irp,
                                ntStatus,
                                info,
                                IO_NO_INCREMENT);

    KdPrint( ("IntUsb_SetWmiDataItem - ends\n"));

    return ntStatus;
}

NTSTATUS
IntUsb_SetWmiDataBlock(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP           Irp,
    IN ULONG          GuidIndex,
    IN ULONG          InstanceIndex,
    IN ULONG          BufferSize,
    IN PUCHAR         Buffer
    )
/*++

Routine Description:

    This routine is a callback into the driver to set the contents of
    a data block. When the driver has finished filling the data block it
    must call WmiCompleteRequest to complete the irp. The driver can
    return STATUS_PENDING if the irp cannot be completed immediately.

Arguments:

    DeviceObject is the device whose data block is being queried

    Irp is the Irp that makes this request

    GuidIndex is the index into the list of guids provided when the
        device registered

    InstanceIndex is the index that denotes which instance of the data block
        is being queried.
            
    BufferSize has the size of the data block passed

    Buffer has the new values for the data block


Return Value:

    status

--*/
{
    PDEVICE_EXTENSION deviceExtension;
    NTSTATUS          ntStatus;
    ULONG             info;

    PAGED_CODE();

    deviceExtension = (PDEVICE_EXTENSION) DeviceObject->DeviceExtension;
    info = 0;

    KdPrint( ("IntUsb_SetWmiDataBlock - begins\n"));

    switch(GuidIndex) {
    
    case WMI_INTUSB_DRIVER_INFORMATION:

        if(BufferSize == sizeof(ULONG)) {

            DebugLevel = *(PULONG) Buffer;
                    
            ntStatus = STATUS_SUCCESS;

            info = sizeof(ULONG);
        }
        else {

            ntStatus = STATUS_INFO_LENGTH_MISMATCH;
        }

        break;

    default:

        ntStatus = STATUS_WMI_GUID_NOT_FOUND;
    }

    ntStatus = WmiCompleteRequest(DeviceObject,
                                Irp,
                                ntStatus,
                                info,
                                IO_NO_INCREMENT);

    KdPrint( ("IntUsb_SetWmiDataBlock - ends\n"));

    return ntStatus;
}

PCHAR
WMIMinorFunctionString (
    UCHAR MinorFunction
    )
/*++
 
Routine Description:

Arguments:

Return Value:

--*/
{
    switch (MinorFunction) {

        case IRP_MN_CHANGE_SINGLE_INSTANCE:
            return "IRP_MN_CHANGE_SINGLE_INSTANCE\n";

        case IRP_MN_CHANGE_SINGLE_ITEM:
            return "IRP_MN_CHANGE_SINGLE_ITEM\n";

        case IRP_MN_DISABLE_COLLECTION:
            return "IRP_MN_DISABLE_COLLECTION\n";

        case IRP_MN_DISABLE_EVENTS:
            return "IRP_MN_DISABLE_EVENTS\n";

        case IRP_MN_ENABLE_COLLECTION:
            return "IRP_MN_ENABLE_COLLECTION\n";

        case IRP_MN_ENABLE_EVENTS:
            return "IRP_MN_ENABLE_EVENTS\n";

        case IRP_MN_EXECUTE_METHOD:
            return "IRP_MN_EXECUTE_METHOD\n";

        case IRP_MN_QUERY_ALL_DATA:
            return "IRP_MN_QUERY_ALL_DATA\n";

        case IRP_MN_QUERY_SINGLE_INSTANCE:
            return "IRP_MN_QUERY_SINGLE_INSTANCE\n";

        case IRP_MN_REGINFO:
            return "IRP_MN_REGINFO\n";

        default:
            return "IRP_MN_?????\n";
    }
}