--- On Fri, 16/4/10, Luiz Augusto von Dentz <luiz.dentz@xxxxxxxxx> wrote: > From: Luiz Augusto von Dentz <luiz.dentz@xxxxxxxxx> > Subject: Re: killing stalled ACL connection > To: "Pavan Savoy" <pavan_savoy@xxxxxxxxxxx> > Cc: linux-bluetooth@xxxxxxxxxxxxxxx > Date: Friday, 16 April, 2010, 1:32 PM > Hi, > > On Thu, Apr 15, 2010 at 10:25 PM, Pavan Savoy <pavan_savoy@xxxxxxxxxxx> > wrote: > > I am working on a platform which has a very aggressive > power management features. > > So consider a situation, where an a2dp connection > exists with a headset, and i pause the media over AVRCP, so > my phone now goes into suspend state (shutting off UART > clocks), > > > > and when I wake-up (resume) using the AVRCP > connection, via the play/pause button, I see the platform > waking up and media player receiving the input, However I > also see this, > > > > hci0 ACL tx timeout. > > killing stalled ACL connection. > > > > and media is not able to play on the headset anymore. > > Although the media player thinks it's being played. > > > > Now where should I look into, as to why a perfectly > nice ACL (l2cap, a2dp) connection was dropped during the > suspend ? > > I guess you mean the system is suspended, to be honest I > thought that > would mean shutting down the bluetooth chip too which > obviously will > drop all the connections, but that doesn't seems to be the > case here, > does it? Anyway if you shutdown the bus which you > communicate with the > chip it could eventually timeout, I guess in such situation > it is > better to enter sniff mode, use some kind of bus that can > wakeup/powerup automatically if there is data to transfer > or a > combination of both. UART does this kind of automatically, I mean there is no s/w calls that are made it go into suspend state. (there is a hardware module which does that - we just have to configure it) And yes, bluetooth chip is actually alive and active after suspend/resume. However it's only the ACL connections that are getting dropped. Is there some sort of timeout involved ? with these ACL connections ? because I guess even the LMP's time to leave messages would not be going to headset (if there is such a thing called TTL messages). I need some hint as to how I can debug this ... > > -- > Luiz Augusto von Dentz > Computer Engineer > -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
