Until the mentioned kernel version I had the binary package from the debian repo (firmware-atheros) installed and everything worked right away.
After the update to 5.10.0-2 I cannot enable it anymore.
The bluetooth service seems to be broken as well:
Feb 09 09:34:49 robot-pc bluetoothd[686]: src/main.c:parse_controller_config() Key file does not have key “LEScanIntervalConnect” in group “Controller”
Feb 09 09:34:49 robot-pc bluetoothd[686]: src/main.c:parse_controller_config() Key file does not have key “LEScanWindowConnect” in group “Controller”
Feb 09 09:34:49 robot-pc bluetoothd[686]: src/main.c:parse_controller_config() Key file does not have key “LEMinConnectionInterval” in group “Controller”
Feb 09 09:34:49 robot-pc bluetoothd[686]: src/main.c:parse_controller_config() Key file does not have key “LEMaxConnectionInterval” in group “Controller”
Feb 09 09:34:49 robot-pc bluetoothd[686]: src/main.c:parse_controller_config() Key file does not have key “LEConnectionLatency” in group “Controller”
Feb 09 09:34:49 robot-pc bluetoothd[686]: src/main.c:parse_controller_config() Key file does not have key “LEConnectionSupervisionTimeout” in group “Controller”
Feb 09 09:34:49 robot-pc bluetoothd[686]: src/main.c:parse_controller_config() Key file does not have key “LEAutoconnecttimeout” in group “Controller”
Feb 09 09:34:49 robot-pc bluetoothd[686]: Starting SDP server
Feb 09 09:34:49 robot-pc bluetoothd[686]: Bluetooth management interface 1.18 initialized
Feb 09 09:34:49 robot-pc systemd[1]: Started Bluetooth service.
Does anybody has an idea what’s wrong now?