[MinnowBoard] MBM Baytrail writing a Sound Card driver for I2S

[Michael Pogrebinsky]

Hi all,
I have the MinnowBoard Max with Baytrail Atom (ValleyView) SoC.
I'm attempting to write a driver for my sound card to work with this board.
PCM should work through I2S for this sound card I have.
I was looking for an I2S bus driver for this SoC and I found this mailing
thread:
https://www.mail-archive.com/elinux-minnowboard@lists.elinux.org/msg01572.html

So I understand that I need the 3 components for my ASoC driver. However I
am having trouble at understanding how to communicate with the LPE to get
the I2S working.

Here is what I have done so far:
I am running Ubuntu 14.04 LTS, kernel : 4.3.0-040300rc4

First of all I downloaded the firmware fw_sst_0f28.bin-48kHz_i2s_master
from
https://kernel.googlesource.com/pub/scm/linux/kernel/git/firmware/linux-firmware/+/refs/heads/master/intel/fw_sst_0f28.bin-48kHz_i2s_master

And put it /lib/firmware/intel/.
Later I went to the Bios and enabled LPE. (For some reason only Enable in
PCI mode makes the LPE controller show up in lshw).

Later I looked at the sound/soc/inte/baytrail/ and from my understanding
inorder for me to get the I2S working I need to load this module so I did
modprobe snd-soc-sst-baytrail-pcm. Later I wrote a simple codec and machine
driver (looking at the example of sound/soc/intel/boards/byt_max98090)
however everytime I attempt to register the sound card with
snd_soc_register_card, I get the following error message in dmesg : "ASoC:
CPU DAI baytrail-pcm-audio not registered".

>From this I deduct that although I loaded the snd-soc-sst-baytrail-pcm
module, the driver has not actually been loaded.
I'm clueless on how to proceed from here.

I would highly appreciate your help.
Thank you
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