Any idea what modules need to be added to get i2s audio working with FriendlyWrt?

I have kmod sound core, alsa, installed ok, but only have these sound devices showing: ( play will play file but no sound)
0 [Dummy ]: Dummy - Dummy
Dummy 1
1 [Loopback ]: Loopback - Loopback
Loopback 1
2 [Codec ]: H3_Audio_Codec - H3 Audio Codec
H3 Audio Codec
3 [allwinnerhdmi ]: allwinner_hdmi - allwinner,hdmi
allwinner,hdmi

In the normal FA install it has a device which works as card 4: which is what I need
4 [I2Smaster ]: I2S-master - I2S-master
I2S-master

TIA.