No snd device found on dm8168 evm board when kernel start

Hi ALL,

I using dm8168 evm+vs board, dvrrdk 2.80 ,

and i run the audio demo ,

snd device can not be found ,

##### MY ENV #####

/dev # ls -al /dev/snd/* 

nothing is found then,

then i see the print information when linux kernel starts,about ALSA

ALSA device list:

no alsa device found 

i see the kernel menuconfigue , i have include the alsa soc option 

Is there any other work have to do for using audio tvp5158 or aix30 on evm board?

or i miss some configure params?

best regards

xavier