I'm able to exchange raw data over L2CAP between Linux host and Beaglebone using Broadcom BCM20702 Bluetooth USB adapter.
But it stops after about 150 transactions!
I did experiment on both Linux host using L@PING from BlueZ and found out it stoped after only 44 pings!!!
So, I'm wondering if it is the limitation of Bluetooth where it expects a disconnection/reconnection for every, say 40 transactions
Unfortunately, the BCM20702 is not supported here on the community website.
You will need to work with your local Broadcom sales team to setup support for this device.