Extend the capabilities of the VirtIO sound device to include features for managing audio settings, such as volume adjustment, muting/unmuting, and mode switching.
this patch introduces the recent support for audio controls in the linux headers used by qemu - https://lore.kernel.org/all/[email protected]/
the audio controls have been added into the VirtIO sound 1.3 specification at - https://docs.oasis-open.org/virtio/virtio/v1.3/csd01/virtio-v1.3-csd01.html#x1-56700014