Return-Path: Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 7.2 \(1874\)) Subject: Re: [PATCH] Bluetooth: Enable duplicates filter in background scan From: Marcel Holtmann In-Reply-To: <1394486784-5431-1-git-send-email-andre.guedes@openbossa.org> Date: Tue, 11 Mar 2014 13:00:24 -0700 Cc: linux-bluetooth@vger.kernel.org Message-Id: References: <1394486784-5431-1-git-send-email-andre.guedes@openbossa.org> To: Andre Guedes Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi Andre, > To avoid flooding the host with useless advertising reports during > background scan, we enable the duplicates filter from controller. > > However, enabling duplicates filter requires a small change in > background scan routine in order to fix the following scenario: > 1) Background scan is running. > 2) A device disconnects and starts advertising. > 3) Before host gets the disconnect event, the advertising is reported > to host. Since there is no pending LE connection at that time, > nothing happens. > 4) Host gets the disconnection event and adds a pending connection. > 5) No advertising is reported (since controller is filtering) and the > connection is never established. > > So, to address this scenario, we should always restart background scan > to unsure we don't miss any advertising report (due to duplicates > filter). > > Signed-off-by: Andre Guedes > --- > net/bluetooth/hci_core.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) patch has been applied to bluetooth-next tree. Regards Marcel