Brain dump of debugging why AX200 Bluetooth is missing under Linux

gistfile1.txt

Key E slot
Key A+E cards

/sys/devices/pci0000:00/0000:00:08.1/0000:04:00.4

Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 13d3:5463 IMC Networks USB2.0 HD UVC WebCam
Bus 001 Device 002: ID 04f3:0c6e Elan Microelectronics Corp. ELAN:Fingerprint
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

cd /sys/kernel/debug/asus-nb-wmi
echo 0x53564544 > method_id
echo 0x00100013 > dev_id
echo 0x2 > ctrl_param
cat call


ECD2 (-> EC66, -> EC62)
Bluetooth sets EC66 to 0xE3

EC66 has 8 bits

FANL (ACPI method)
ASUS_WMI_DEVID_KBD_BACKLIGHT
ASUS_WMI_DEVID_FNLOCK sets EC66 to 0x72 (0b01110010)

ASUS_WMI_DEVID_BLUETOOTH sets EC66 to 0xE3 (0b11100011)

76543210
      ^
      |- seems to be some kind of busy state, inferring from ECD2

Reading EC66 returned 0x8 (0b00001000)

_SB.PCI0.SBRG.EC0.WIBE Method       00000000829240c2 001 Args 1 Len 005D Aml 00000000ba75adfa