At Wed, 9 May 2007 23:07:11 +0200 (CEST), Vegard Nossum wrote:
Hello,
I've successfully debugged a problem I've had with being unable to record anything from microphones or line-in. Detailed information about the bug along with a temporary work-around can be found here: http://bugtrack.alsa-project.org/alsa-bug/view.php?id=3066
Now I'd just like to inform about the presence of the bug (at least I'm pretty sure it's a bug), and that it's solved by the means of a work-around. I'd be very happy to see a fix in the *code* for this, however. I'd even like to try it myself (heck, it's just a register write), but I'm not certain WHERE/WHEN to make the write, under which conditions, and for which range of cards (ie. is it specific to the ALC655 or ALC*, or perhaps Realtek chips, or should the fix be made for the Intel driver, or all AC'97 cards?). Guidance would be appreciated :) Maybe it's even as easy as a card config option, but I wouldn't know.
Finally have some time to reach this report... We still need to check whether it's really a driver bug or a user problem. Please test the following:
- Check the generated file via "alsactl -f somefile store". Attach this file. - This should contain "Capture Source" enum item. You can modify that file (change value.0 and value.1), then run alsactl -f somefile restore to put the value. - Look at ac97#0-0+regs proc and check whether the register 0x1a is changed by that. - Finally test the PCM recording via hw:0,0.
The appearance on alsamixer is somehow confusing. It appears not as a "Capture Source" but individual items like "Mic", "Line", etc on capture mode. Then you can choose it by pressing a space key. Since this is a mux, another selected source will be automatically deselected.
thanks,
Takashi