On Mon, Feb 18, 2019 at 4:58 AM Marcel Holtmann <marcel@xxxxxxxxxxxx> wrote: > > Hi Andrey, > > > Due to: > > > > - current implementation of l2cap_config_rsp() dropping BT > > connection if sender of configuration response replied with unknown > > option failure (Result=0x0003/L2CAP_CONF_UNKNOWN) > > > > - current implementation of l2cap_build_conf_req() adding > > L2CAP_CONF_RFC(0x04) option to initial configure request sent by > > the Linux host. > > > > devices that do no recongninze L2CAP_CONF_RFC, such as Xbox One S > > controllers, will get stuck in endless connect -> configure -> > > disconnect loop, never connect and be generaly unusable. > > > > To avoid this problem add code to do the following: > > > > 1. Store a mask of supported conf option types per connection > > > > 2. Parse the body of response L2CAP_CONF_UNKNOWN and adjust > > connection's supported conf option types mask > > > > 3. Retry configuration step the same way it's done for > > L2CAP_CONF_UNACCEPT > > > > Signed-off-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx> > > Cc: Pierre-Loup A. Griffais <pgriffais@xxxxxxxxxxxxxxxxx> > > Cc: Florian Dollinger <dollinger.florian@xxxxxx> > > Cc: Marcel Holtmann <marcel@xxxxxxxxxxxx> > > Cc: Johan Hedberg <johan.hedberg@xxxxxxxxx> > > Cc: linux-bluetooth@xxxxxxxxxxxxxxx > > Cc: linux-kernel@xxxxxxxxxxxxxxx > > --- > > > > Everyone: > > > > I marked this as an RFC, since I don't have a lot of experience with > > Bluetooth subsystem and don't have hight degree of confidence about > > choices made in this patch. I do, however, thins is is good enough to > > start a discussion about the problem. > > can you take a btmon -w trace.log protocol trace so that I can see where it fails. This seems a really odd behavior of the Xbox controller. We have to be careful in not breaking Bluetooth qualification to just workaround some buggy remote device. > Sure, n/p, both "failure" (behavior before this patch) and "success" (behavior with the patch) cases on my machine are available here: https://gist.github.com/ndreys/2b74094933601978e200af1ff0a55372 Let me know if that's not accessible to you. Thanks, Andrey Smirnov
