Hi Colin, David<br><br>I can see David posts on the group recently and assuming David is back from vacations :)<br>unfortunately we don't access to IRC chat due to some security restriction (thou we are working to get this sorted, if possible) so currently I can discuss only over group emails.<br> <br><div class="gmail_quote">On Fri, Jul 22, 2011 at 1:42 AM, Colin Guthrie <span dir="ltr"><<a href="mailto:gmane@colin.guthr.ie" target="_blank">gmane@colin.guthr.ie</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> 'Twas brillig, and Himanshu Chug at 21/07/11 08:24 did gyre and gimble:<br> <div>> Thanks Colin and Spidey for making this clarification.<br> ><br> > So regarding JACK detection and routing:<br> ><br> > 1. module-udev-detect currently can detect JACK physical hot-plugging<br> > but it can't decode the information about what type of JACK device (<br> > input or output ) is connected to the sound-card, and for that one need<br> > to write an JACK detection module to handle that.<br> > is my understanding correct ?<br> <br> </div>Not quite. Udev detect does absolutely nothing with JACKs. It detects<br> totally new devices in a hotplug way. These devices are e.g. USB<br> speakers or headsets.<br></blockquote><div><br>one colleague of mine from ALSA /kernel team have wrote the Jack detection app using udev API from libudev, <br>so the Jack plug in/plug Out state can be read at <font color="#000099">sys/devices/virtual/<span>switch</span>/h2w/state<br> </font><div><font color="#000099"> </font></div><div><font color="#000099"> </font>State Meaning<br> 0 No Headset Connected<br> 1 Headset with MIC connected <br></div> <div> 2 Headset without MIC connected<br><br>here we are monitoring in a loop using udev monitor fd and based on the "state" we are calling kcontrols for loudspeaker and headset<br>something like here...<br> <br>fd = udev_monitor_get_fd(mon);<br> <br>while (1) {<br>............<br>r = select(fd, ...);<br><br>dev = udev_monitor_receive_device(mon);<br>if (dev) {<br> // Jack Inserted/Removed <br> Jack_Report(state); // this function will call kcontrols for headset/loudspeaker based on "state"<br> }<br>............<br>}<br><br>I am trying to understand if this approach of Jack detection is fine? at-least I need to know if I am going in right direction? <br></div> <br><br></div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> <br> The actual HP Jack detection stuff is not present at all in PA as the<br> underlying layers in ALSA are in flux. These need to settle before we<br> can write anything to deal with them.<br></blockquote><div><br>As Colin comments about ALSA layers are in flux, I need to understand this bit more some brief information about this problem with ALSA ?<br>if you can point to some link or so is also fine :)<br> <br><br></div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> <br> There are active discussions on this topic just now on the alsa-devel<br> mailing list.<br> <div><br> <br> > 2 Currently our Kernel/ALSA team support for providing seperate kcontrol<br> > (amixer scripts) for enabling/disabling loudspeaker and headset to PA,<br> > so it might be an good idea to handle Jack detection and routing in one<br> > of the existing module or write up an new jack detection module for<br> > this, as Colin suggested, provided that we are able to recognize Jack<br> > device type (input/mic or output/headset or both) from point 1, ( i<br> > will take further help from kernel team here about detecting jack device<br> > type, but any suggestions are welcome :-) )<br> <br> </div>Kinda. PA should be able to display to you the different "ports" for<br> each sink. These ports represent the Speakers or the Headphones<br> kcontrols that are on your device and you can change ports at runtime<br> (just run pavucontrol and if your sinks actually have ports, there will<br> be a drop downo n the "Output Devices" pane). </blockquote><div><br>I am not able to get pavucontrol installed and working on my rootstrap, due to some other issues, but I need to test this out also soon.<br> but I tried on UBUNTU 10.10 desktop, pavucontrol app showing me the dropdown for Output Devices, <br> </div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">At present you have to<br> change ports manually but the plan is to hook this up to jack detection,<br> such that the port is simply flipped accordingly.<br></blockquote><div><br>I need to know where (or how) in code we can do "flipping of ports from headphones to loudspeaker" <br>if I use our udev API for jack detection from above ? <br> </div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> <br> Multifunction jacks (i.e. those that can be input or output, analog or<br> digital) are even more interesting :)<br> <br> <br> I very strongly suggest you discuss this with David Henningsson. He's on<br> this list but is away on vacation for (I think) another week. He's is<br> actively working on JACK support for ALSA and PA layers so it will<br> likely be the most productive for you if you wait and speak with him.<br> He's employed by Canonical and is diwic on IRC.<br> <div><div></div><div><br> <br> Col<br> <br> <br> --<br> <br> Colin Guthrie<br> gmane(at)<a href="http://colin.guthr.ie" target="_blank">colin.guthr.ie</a><br> <a href="http://colin.guthr.ie/" target="_blank">http://colin.guthr.ie/</a><br> <br> Day Job:<br> Tribalogic Limited [<a href="http://www.tribalogic.net/" target="_blank">http://www.tribalogic.net/</a>]<br> Open Source:<br> Mageia Contributor [<a href="http://www.mageia.org/" target="_blank">http://www.mageia.org/</a>]<br> PulseAudio Hacker [<a href="http://www.pulseaudio.org/" target="_blank">http://www.pulseaudio.org/</a>]<br> Trac Hacker [<a href="http://trac.edgewall.org/" target="_blank">http://trac.edgewall.org/</a>]<br> </div></div></blockquote></div><br>