Bluetooth profile driver issue (BRB_L2CA_OPEN_CHANNEL etc) RRS feed

  • Question

  • Hello,

    I have almost finished my Bth profile driver and am testing it for quality control. During the test, I have been confronted with an issue.

    That is, if I am sending BRB_L2CA_OPEN_CHANNEL request to the BTH stack to open connection with a client device, it normally works well. However if I plug the BTH USB dongle out from USB port around 3~4 seconds after sending the BRB request, the BTHPORT freeze for 60~70 seconds and doesn't capture that the BTH dongle was disconnected. Therefore, every BTH related drivers (BTHENUM, BTHPORT, BTH...) won't be unloaded during the period (60~70 seconds). That 60~70 seconds period is identical for both x86 Win7 and x64 Win8. Therefore I think it may be deterministic error rather than arbitrary.

    I have tried some workaround such as request timeout setup or io cancellation, but they did not resolve the issue. So I want to know...

    1) Do you think it is my own driver's issue or Windows BTH stack itself issue?

    2) Please let me know if you have any clue about the issue.

    Thanks in advance.

    SJ Lee

    Wednesday, August 19, 2015 9:59 AM

All replies

  • Finally I have found easy step to confirm the error. I mind this must be a Windows Bluetooth stack bug.

    1. Prepare 1 Bluetooth USB dongle equipped Windows 7 PC and 1 Windows 8 PC.

    2. Pair the 2 PCs with Bluetooth.

    3. In Windows 7 PC, open "Devices and Printers" ("Control Panel" -> "Devices and Printers"). Right-click the Bluetooth paired Windows 8 PC and click the "Connecting using" and "Direct connection" in the popup menu.

    4. Unplug the Bluetooth USB dongle 3~4 seconds after above operation.

    That's it. You can see Windows keep trying to connect during 60~70 seconds and all the Bluetooth drivers won't be unloaded during the period.

    Friday, August 21, 2015 11:03 AM
  • Even worse, after ~ 5 trial of the experiment, my Windows 7 PC did not load the Bluetooth USB dongle drivers any more.
    Friday, August 21, 2015 11:11 AM
  • I have 2 models. One is for legacy Bluetooth version that does not support SSP(Secure Simple Pairing) and the other is Bluetooth version 2.0 or later that support SSP. Both are based on CSR chipset.

    And the symptoms are same on both dongles.

    Friday, August 21, 2015 5:02 PM