tree ecdf75859e73b7671550204c42d1dd6949bb8288
parent 89b4ab213feb11a5bece544cfa12374f66c2c47c
author Jorge Sanjuan <jorge.sanjuan@codethink.co.uk> 1533040122 +0100
committer Takashi Iwai <tiwai@suse.de> 1533042082 +0200

ALSA: usb-audio: Initial Power Domain support

Thee USB Audio Class 3 (UAC3) introduces Power Domains as a new
feature to let a host turn individual parts of an audio function
to different power states via USB requests. This lets the device
get to know a bit amore about what the host is up to in order to
optimize power consumption efficiently.

The Power Domains are optional for UAC3 configuration but all
UAC3 devices shall include at least one BADD configuration where
the support for Power Domains is compulsory.

This patch adds a set of features/helpers to parse these power
domains and change their status.

Signed-off-by: Jorge Sanjuan <jorge.sanjuan@codethink.co.uk>
Signed-off-by: Takashi Iwai <tiwai@suse.de>