USB Audio Class 3.0 Improvements Coming To Linux 4.18
UAC3 is primarily geared for "USB audio over USB Type-C" that is an upgrade over UAC2 with improved power management, new descriptors, and more.
One of the primary additions for the UAC3 support in Linux 4.18 is supporting BADD, the Basic Audio Device Definition. BADD provides a set of USB device configurations that are considered mandatory for UAC3 devices. Details on UAC3 BADD are outlined by this commit.
There are also other USB audio improvements currently queued in the sound's "next" branch for landing next month in the Linux 4.18 development cycle.