From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Wed, 18 Oct 2017 14:16:11 +0300 From: Johan Hedberg To: Bastien Nocera Cc: linux-bluetooth@vger.kernel.org Subject: Re: Surface 3 Pen (BLE HID) not sending events Message-ID: <20171018111611.GA8301@x1c.lan> References: <1508258502.5910.68.camel@hadess.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1508258502.5910.68.camel@hadess.net> Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi Bastien, On Tue, Oct 17, 2017, Bastien Nocera wrote: > The Surface 3 pen (part of the 2nd generation of Surface pens[1]) uses > Bluetooth LE for its top button, which one can assign to a function, > usually a note taking application on Windows. > > After pairing, bluez throws away all the characteristics, UUIDs and > other properties it gathered[2]. > > Subsequent attempts at pressing the pen button just throws a wobbly[3]. > > Any ideas? This apparently used to work, and there's some very hacky > solutions for those devices: Do you happen to have a btmon log of the pairing? The reason could e.g. be that the device doesn't set the bonding flag (in which case our discarding of information is at least specification-wise correct). The HCI log you posted seems to be a reconnection when pairing has already happened. Also, please avoid using hcidump since it does a worse job of decoding stuff (especially newer protocol features). Johan