1. A method comprising: receiving data from an accessory device at an intermediate processor of a computing device, the data usable to enumerate functionality of the accessory device for operation as part of a computing device that includes the intermediate processor; receiving a request at the intermediate processor from the accessory device for reports that are usable by the accessory device to perform power management; and passing the data by the intermediate processor to an operating system executed on processor of the computing device to enumerate the functionality of the accessory device.