Return-Path: Subject: btusb regression on commands unsupported by adapter From: Jeremy Jackson To: linux-bluetooth@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Date: Fri, 18 Dec 2009 12:44:32 -0500 Message-ID: <1261158272.4932.184.camel@ragnarok> Mime-Version: 1.0 Sender: linux-bluetooth-owner@vger.kernel.org List-ID: I've posted more details here for userspace diagnosis/workaround, https://bugs.launchpad.net/ubuntu/+source/linux/+bug/377225 Some (older?) BT adapters don't support the commands 'Read Default Link Policy Settings' 'Write Default Link Policy Settings' as shown by # hciconfig hci0 commands This appears be one cause of the infamous kernel message: hci0: command tx timeout. This in turn causes bluetoothd to give up and take down the interface. If you kill bluetoothd, and manually # hciconfig hci0 up, you can discover and inq devices no problem. I made a patch to disable the offending command, and the above mentioned bug report I gave instructions to gather data on adapter BT version, supported features, and supported commands. Hopefully some user reports can be used to make use of the command conditional on actual adapter support. The question for kernel side is, regression, or corrected behaviour? -- Jeremy Jackson Coplanar Networks (519)489-4903 http://www.coplanar.net jerj@coplanar.net