[Angstrom-devel] Modifying audio register value in Angstrom
alfayez at aol.com
Mon Sep 20 23:00:58 CEST 2010
Hi, I'm running the Angstrom on the Beagleboard and I'm trying to find a way to modify the audio rate register values to force sampling rates other than 44.1 kHz and 48 kHz. Basically when I run "cat /sys/devices/platform/soc-audio/codec_reg" register 0x1 reads 0x91 which from the datasheet means the sampling rate = 44.1kHz. I'm trying to set register 0x1 to 0x81 to force it to run at 32 kHz. but the "echo 1 81 > codec_reg" command is apparently not supported and from the angstrom the register is read-only I even tried chmod +w the register but that didn't work.
I tried using debugfs to modify the register value unfortunately the functionality isn't available through that. I found a few listings online of ALSA patches that expose the register during debugfs, after copying and pasting them I still couldn't access the register. When I tried modifying the twl4030.c driver in the openembedded directory linux-omap-2.6.28/git/audio/soc/twl4030.c by basically hardcoding the reigster value to 0x81 it still didn't work.
I'm running the 2.6.28. can anyone share some advice ???
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