The framework that lets a Linux device act as a USB peripheral rather than a USB host, so that boards like Raspberry Pi Zero, Android phones, embedded gadgets, and development boards can present themselves to a PC as a network adapter, mass storage device, serial port, MIDI device, webcam, or composite combination of these.
This is not a single driver but an entire subsystem tree. It contains the libcomposite core framework, a collection of function drivers (mass storage, Ethernet, serial, audio, HID, etc.), legacy gadget configurations, and the USB device controller drivers that talk to actual silicon. Each component would need to be evaluated on its own; the directory as a whole is core Linux infrastructure used by countless embedded and mobile systems.
repository signals
172files
146,140source lines
899commits, 5y
+29,236 / −22,911lines added / removed, 5y
260authors, 5y
monthly commits · 2021-04-21 → 2026-04-21 · 899 total · active in 61/61 months
sources
No sources cited.
codex reasoning notes (technical)
Not a driver directory: umbrella USB gadget subsystem containing libcomposite framework code plus multiple function/legacy/udc drivers, not one kernel-bound hardware driver