'Twas brillig, and Lin, Mengdong at 28/07/11 07:50 did gyre and gimble: > I found the module-echo-cancel's "Echo-Cancel Source Stream" can be > created on a monitor source of an new created ALSA sink by mistake, if > the real ALSA source is not created yet. > > Could anyone tell me how to fix this issue? I could have helped debug this better had I been aware of the Intel AppUp presentation yesterday where they were able to supply MeeGo EXOPC tablets to developers. Sadly I missed this session as I was too busy hacking on PA and didn't get one. Very frustrating as just about everyone I can see here today now has one of these devices :( Is this one of the devices that exhibits this hardware setup? Anyway, I'll try and help in a "theory only" mode.... > On my MeeGo platform, the ALSA sink/source don?t always exist because > the ALSA and Bluetooth HSP headset share one hardware data link. So when > BT HSP headset is connected, ALSA card will change into a ?hsp? profile > , remove the ?normal? ALSA sink/source pair and create a ?hsp? > sink/source pair for BT. And after BT HSP headset is disconnected, ALSA > card restores its original profile, remove ?hsp? sink/source and create > ?normal? ALSA sink/source again. > > > > My problem is that when BT HSP is disconnected during a phone call, I > got the above routing error and a pa deadlock described in another loop: > http://lists.freedesktop.org/archives/pulseaudio-discuss/2011-July/010741..html > <http://lists.freedesktop.org/archives/pulseaudio-discuss/2011-July/010741.html> > > The module-echo-cancel is loaded again when the VOIP stream is routing > back to the new created ALSA sink. But because the ALSA source is not > created yet (will be later), PA routes the ?Echo-Cancel Source Stream? > to the monitor source of the ALSA sink. One solution is perhaps to modify the echo cancel module to use the DONT_MOVE flags. This would prevent PA moving it at all and instead kill the stream which should, I think, ultimately unload the echo-cancel module completely. Hopefully then when the other stuff is loaded a new echo-cancel module will then be loaded. This seems like a bit of a nasty cycle tho', and I can't help but feel there is a better way :( > How to make ?Echo-Cancel Source Stream? link to the right ALSA source, > which will be created a little later? Longer term, obvious this whole nasty situation would be avoided with a properly filter API rather than this system of using virtual sinks, but we have to work with what we've got now. I'll try and give the problem a little thought and get back to you if I come up with anything. Col -- Colin Guthrie gmane(at)colin.guthr.ie http://colin.guthr.ie/ Day Job: Tribalogic Limited [http://www.tribalogic.net/] Open Source: Mageia Contributor [http://www.mageia.org/] PulseAudio Hacker [http://www.pulseaudio.org/] Trac Hacker [http://trac.edgewall.org/]
