I recently installed yosemite OS X public beta. My laptop is Dell Inspiron n5520 and specs are as follows:
cx20561 conexant audio
elantech touchpad builtin
hd 4000 intel graphics alone no amd
So the problem is that i have installed all of the voodooHDA kexts i could have ever found on the internet( version 2.8.4 and above) all of them returned with just nothing. For example in the extensions tab in the system report VoodooHDA showed :
Last Modified: 05/04/2014 1:07 pm
Bundle ID: org.voodoo.driver.VoodooHDA
Obtained from: Unknown
64-Bit (Intel): Yes
Kext Version: 2.8.5
Signature Validation Errors: Kext signature validation error code -67030
Signed by: Unknown
And I was unable to find any appleHDA.kext for cx 20561 for yosemite, but still it should load, and i don't think signature matters really.
I installed the VoodooHDA kext through Vietnam hackintosh tool and through other sources the signed ones showed the same error.
HAH! Stuck why not loaded .
PROBLEM SOLVED I just had to boot with kext-dev-mode=1 flag and worked like a rocket