BM308 Tecknet mouse bluetooth fix

# Tecknet BM308 mouse not working under Linux (ArchLinux)

# correctly registered hci0 device in linux kernel / firmware (intel patch)

[root@terminator bluetooth]# dmesg | grep -i blue
[    3.114988] Bluetooth: Core ver 2.22
[    3.114999] Bluetooth: HCI device and connection manager initialized
[    3.115004] Bluetooth: HCI socket layer initialized
[    3.115006] Bluetooth: L2CAP socket layer initialized
[    3.115009] Bluetooth: SCO socket layer initialized
[    3.130889] Bluetooth: hci0: read Intel version: 370810225019140f00
[    3.131626] Bluetooth: hci0: Intel Bluetooth firmware file: intel/ibt-hw-37.8.10-fw-22.50.19.14.f.bseq
[    3.497875] Bluetooth: hci0: Intel firmware patch completed and activated
[    5.692652] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
[    5.692655] Bluetooth: BNEP filters: protocol multicast
[    5.692663] Bluetooth: BNEP socket layer initialized
[   32.350410] Bluetooth: RFCOMM TTY layer initialized
[   32.350415] Bluetooth: RFCOMM socket layer initialized
[   32.350418] Bluetooth: RFCOMM ver 1.11
[  885.573144] Bluetooth: HIDP (Human Interface Emulation) ver 1.2
[  885.573153] Bluetooth: HIDP socket layer initialized
[ 3209.998987] Bluetooth: hci0: last event is not cmd complete (0x0f)
[ 5115.001900] Bluetooth: hci0: last event is not cmd complete (0x0f)
[ 5138.203145] bluetoothctl[17302]: segfault at 0 ip 00007fd3eff87c22 sp 00007ffde1004d08 error 4 in libc-2.28.so[7fd3efe4f000+14b000]
[ 5192.995897] Bluetooth: hci0: last event is not cmd complete (0x0f)
[ 5256.797361] input: BM30X mouse as /devices/pci0000:00/0000:00:14.0/usb1/1-3/1-3:1.0/bluetooth/hci0/hci0:256/0005:0A5C:4503.0006/input/input27
[ 5256.797626] hid-generic 0005:0A5C:4503.0006: input,hidraw3: BLUETOOTH HID v1.29 Mouse [BM30X mouse] on 30:e3:7a:e7:fa:f3
[ 5265.001977] Bluetooth: hci0: last event is not cmd complete (0x0f)

# logs seem ok at first but mouse is detected but cannot connect (cannot get HDIP info...)

# what worked for me: https://wiki.archlinux.org/index.php/Bluetooth_mouse

bluetoothctl
power off
power on
scan on
# spot mouse mac bt mac address
remove DC:2C:26:AC:E9:45
trust  DC:2C:26:AC:E9:45
connect DC:2C:26:AC:E9:45
#connect DC:2C:26:AC:E9:45
unblock

#Device DC:2C:26:AC:E9:45 BM30X mouse

or with bash: startbtm.sh
#!/bin/bash
bluetoothctl < startbtm.config

startbtm.config
###############
power off
power on
scan on
remove DC:2C:26:AC:E9:45
trust  DC:2C:26:AC:E9:45
connect DC:2C:26:AC:E9:45
connect DC:2C:26:AC:E9:45
unblock