At Fri, 19 Jun 2009 02:50:35 +0300, Maxim Levitsky wrote:
Hi,
Due to lack of time, I didn't update kernel on my desktop system. Now I notice that analog loopback go removed. Why?
Because it harms than helps more often. I've got tons of bug reports and been upset just because users blindly set "Analog Loopback" mixer switch and lost their sound output. This is no mixer element that behaves intuitively -- it shuts out PCM output instead of adding the analog loopback like other hardwares.
The feature is still available, though. You just need to give the driver an instruction via sysfs. Namely, write to sysfs files corresponding to the IDT codec like # echo "loopback yes" > /sys/class/sound/hwC0D0/hints # echo 1 > /sys/class/sound/hwC0D0/reconfig Then the driver will reconfigure with the loopback mixer element. I have a patch series to add this with a "patch" firmware file to make it easier, which I'm going to send an RFC to this ML soon later. Take a look at topic/hda-patch branch on sound-unstable tree.
thanks,
Takashi