USB MIDI 2.0 Gadget Function Driver Merged For Linux 6.6, Lunar Lake USB Work

The USB/Thunderbolt subsystem updates were merged this past weekend for the ongoing Linux 6.6 kernel merge window.

Last cycle with Linux 6.5 the initial MIDI 2.0 audio driver support was merged. Now with Linux 6.6 there is USB MIDI 2.0 Gadget Function Driver being introduced for MIDI 2.0 compatible devices interfacing with Linux systems via USB. The USB MIDI 2.0 Gadget Function Driver "f_midi2" has gadget functionality provided with the ALSA UMP helper functions and supports MIDI 2.0 with fall-back to MIDI 1.0 if necessary. This gadget driver can be configured using ConfigFS and was developed by Linux sound subsystem maintainer Takashi Iwai, who also worked on the original MIDI 2.0 patches for Linux that were merged in Linux 6.5.

Also notable with the USB updates for Linux 6.6 is adding initial Lunar Lake IOM support to the intel_pmc_musc USB Type-C driver. A new device ID and a few other small changes are needed for enabling the Intel Lunar Lake support relative to the existing Meteor Lake driver support.

There are also intel_pmc_mux driver updates around properly configuring active and retimer cable types as needed in Thunderbolt alternate mode.

More details on all of the USB feature changes for Linux 6.6 via this pull request that has since been merged to the Git master branch.