USB bluetooth controller still appears even though hardware no longer present

Machine is running 16.04 LTS, current on updates.

I had an IOGear USB bluetooth adapter. Worked reasonably well. At one point I pulled it out to give to my son. Like a fool I just yoinked it out hot. Now I have a replacement, a IOGear GBU521 (which I think was the same as the original). I can’t get it to work, and I am suspecting it’s because the machine insists the previous adapter is still present.

Here is lsusb:

Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 007 Device 002: ID 051d:0002 American Power Conversion Uninterruptible Power Supply Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 005 Device 002: ID 046d:c517 Logitech, Inc. LX710 Cordless Desktop Laser Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 009 Device 002: ID 05e3:0612 Genesys Logic, Inc.  Bus 009 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 008 Device 002: ID 05e3:0610 Genesys Logic, Inc. 4-port hub Bus 008 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 003: ID 058f:6362 Alcor Micro Corp. Flash Card Reader/Writer Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 002: ID 0a5c:21e8 Broadcom Corp. BCM20702A0 Bluetooth 4.0 Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub 

and hciconfig:

hci0:   Type: BR/EDR  Bus: USB     BD Address: 00:02:72:C8:AC:34  ACL MTU: 1021:8  SCO MTU: 64:1     UP RUNNING      RX bytes:1038 acl:0 sco:0 events:63 errors:0     TX bytes:4962 acl:0 sco:0 commands:63 errors:0 

bluetoothctl list shows:

Controller 00:02:72:C8:AC:34 khym [default] 

The remove command in bluetoothctl does nothing (says “not available”).

I tried wiping the entries in /var/lib/bluetooth, but the entry for the phantom controller keeps returning. I also found and removed the firmware file /lib/firmware/brcm/BCM20702A1-0a5c-21e8.hcd.

Boot messages include:

Sep 12 23:11:17 khym kernel: Bluetooth: hci0: BCM: chip id 63 Sep 12 23:11:17 khym kernel: Bluetooth: hci0: khym Sep 12 23:11:17 khym kernel: Bluetooth: hci0: BCM20702A1 (001.002.014) build 0000 Sep 12 23:11:17 khym kernel: bluetooth hci0: Direct firmware load for brcm/BCM20702A1-0a5c-21e8.hcd failed with error -2 Sep 12 23:11:17 khym kernel: Bluetooth: hci0: BCM: Patch brcm/BCM20702A1-0a5c-21e8.hcd not found 

When I plug in the new adapter I get an appropriate entry in lsusb and hciconfig, but the gnome bluetooth panel doesn’t recognize it.

I’m thinking since the original controller worked without trouble, if I can get the machine to forget about it the new one should come up without further trouble.

A couple other notes: – This machine is somewhat old (core 2 duo) and currently has a dead CMOS battery so I get corrupted memory messages in my boot logs. Everything else works fine so I believe that isn’t relevant – Machine is using nvidia drivers for graphics (I know that was an issue years ago but is it still?)

I did a fair bit of searching, tried to infer where things are and how files should be based on posts of people getting their btusb to be recognized, but I haven’t come across anyone with the opposite problem!

Thanks in advance for any suggestions for further diagnosis!

ken

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(myenv) $   python script.py 

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(myenv) $   sudo python script.py 

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$   sudo lshw -c display   *-display UNCLAIMED               description: VGA compatible controller        product: GP102 [GeForce GTX 1080 Ti]        vendor: NVIDIA Corporation        physical id: 0        bus info: pci@0000:01:00.0        version: a1        width: 64 bits        clock: 33MHz        capabilities: pm msi pciexpress vga_controller bus_master cap_list        configuration: latency=0        resources: memory:f6000000-f6ffffff memory:e0000000-efffffff memory:f0000000-f1ffffff ioport:e000(size=128) memory:c0000-dffff 

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