Supporting Multifunction Devices On Other Buses

For a multifunction device on a PnP ISA, USB, or IEEE 1394 bus, the parent bus driver enumerates the individual functions if the device conforms to the bus standard.

For such a device, the parent bus driver manages the fact that there is more than one device residing at a single bus location. To the rest of the system, the individual functions operate like independent devices.

Vendors of this type of multifunction device must do the following:

• Ensure that the device conforms to the specification for the bus on which the device will reside.

• Provide a PnP function driver for each function of the device.

  Since the system-supplied bus driver handles the multifunction semantics, the function drivers can be the same drivers that are used when the functions are packaged as individual devices.

• Provide an INF file for each function of the device.

  The INF files can be the same files that are used when the functions are packaged as a individual devices. The INF files do not need any special multifunction semantics.

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Build date: 11/16/2013