Writing Windows WDM Device Drivers
A nuts-and-bolts reference highlighting the Windows Driver Model (WDM).
TABLE OF CONTENTS Writing Windows WDM Device Drivers
Other PnP IRPs
This section briefly describes the Plug and Plug minor function code IRPs that have not been described in full before. These IRPs are handled by PnP bus drivers. The notes for each function code indicate if it is possible for a function driver to intercept the IRP.
Most function drivers ignore all these PnP IRPs. However, a function driver that performs Power Management may well want to handle IRP_MN_QUERY_CAPABILITIES. The following chapter describes how this is done.
IRP_MN_DEVICE_USAGE_NOTIFICATION
This message tells a driver if its device is in the path of a paging, hibernation, or crash dump file. Do not allow a device to be removed until you are notified that no critical file is on its path.
IRP_MN_FILTER_RESOURCE_REQUIREMENTS
The Windows 2000 PnP Manager sends this IRP to a device stack so filter and function drivers can adjust the resources required by the device, if appropriate. Function, filter, and bus drivers can handle this request.
IRP_MN_QUERY_BUS_INFORMATION
The PnP Manager uses this IRP to request the type and instance number of a device's parent bus.
Bus drivers should handle this request for their child devices (PDOs). Function and filter drivers do not handle this IRP.
IRP_MN_QUERY_CAPABILITIES
The PnP Manager sends this IRP to get the capabilities of a device, such as whether the device can be locked or ejected, and various Power Management features. Function and filter drivers can handle this request if they alter the capabilities supported by the bus driver. Bus drivers must handle this...
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