I also want to use this I2S codec. However, the I2S/Edison hardware is not supported by the kernel. This is why you only see the Loopback device.
Have a look at this thread :
I took a quick look at the links you attached on your last post, and I noticed that it is an ALSA diver, so why don't you try installing the ALSA packages available in AlexT's Repo. Also I believe this thread might interest you: Re: Audio via I2S on edison.
Edit: Sorry I didn't see the reply above until I posted mine.