https://bugs.freedesktop.org/show_bug.cgi?id=106957
--- Comment #4 from prg@cooco.de --- # cat /sys/bus/pci/devices/0000:02:00.0/power/runtime_usage 1
# cat /sys/bus/pci/devices/0000:02:00.0/power/runtime_active_kids 0
# cat /sys/bus/pci/devices/0000:02:00.1/power/runtime_usage 0
# cat /sys/bus/pci/devices/0000:02:00.1/power/runtime_active_kids 0
# lsof /dev/snd/controlC1
No output. Yes, I did run this as root.