On Monday 21 July 2008, Andy Green wrote: > Somebody in the thread at some point said: snip my comment about alsa settings bypassing the ALC
> I don't know why we go around it, but when I looked mic -> GSM routing > some weeks ago I also found a very direct analogue path. If you're > interested to meddle with this, I have some meddling hints. First, the > datasheet is open: > > http://www.wolfsonmicro.com/uploads/documents/en/WM8753.pdf I've been reading it already ;-) One area the wiki does well on is links to the hardware datasheets. > We have fitted 100n in the external ALC path (between ACOP / ACIN) > instead of 1uF recommended, I guess it will impact low end, but in > telephony the low end as well as the high end are chopped out anyway. > Soon, as steve told, you'll be able to see this stuff (and our mistakes) > on the schematics for yourself. I didn't notice a rolled off low end in cursory testing of the ALC, so you're probably right. It's good to know just in case though. Steve's announcement was a pleasant surprise, and I'm looking forward to it. > You can dump the actual codec registers using > > # cat /sys/devices/platform/soc-audio/codec_reg > > and you can meddle with them like this > > # echo "3d 20" > /sys/devices/platform/soc-audio/codec_reg_write > > first one is the register address in hex, second is value to write in > hex. I don't really know what those dozens of alsamixer settings are > doing either, I found it easier to read the datasheet and interpret / > meddle with the codec registers directly. That'll be handy. I'll check my mapping of the ALSA devices and settings against this. I don't want to stick it on the wiki before I know it's right. _______________________________________________ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community