USB driver updates: topology and transfer reference

Topology comes before function

A USB stack represents a host controller, hubs, addresses, devices, configurations, and interfaces before a particular function is exposed. A physical product can present multiple interfaces, so the product name and the device-function record are not interchangeable.

Descriptors establish identity

USB descriptors describe device, configuration, interface, endpoint, and capability metadata. Their fields help the host understand what a device presents and which class or vendor relationship may apply. A descriptor is structured interface data, not a complete product review.

Endpoints define transfer contracts

Control, bulk, interrupt, and isochronous endpoints describe different transfer roles and timing expectations. A function component uses those contracts to expose storage, input, audio, camera, or another higher-level interface. Transfer type and user-facing function are adjacent layers.

Shared classes and vendor functions

Standard USB classes can use shared class support. A vendor-specific interface may add controls or behavior through another package or service. One device can therefore have several related records with different providers and release histories.

Package and runtime records

A package can declare matching identifiers, class relationships, files, services, and signatures. Enumeration, matching, selection, activation, transfer, and removal describe runtime and lifecycle states separately, so a package version does not by itself describe live bus traffic.

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