Hello,
I apologize for the delay.
Can you please try using the below commands?
# hciattach /dev/ttymxc2 qca
# rfkill list
# rfkill unblock bluetooth
# sudo hciconfig hci0 up
After that, use the hcitool Linux tool, to set the Bluetooth connection between the devices.
Hope this can help you.
Best Regards,
Diego.