I2s driver for the low speed expansion header

Hi,

Someone from linaro can help in getting the i2s driver for the low-speed expansion header in hikey.

Currently, there is only one i2s driver in the hikey ie for interface s2 (BT).

Can anyone help me in the direction from where I can get the driver or the information which helps me to write i2s driver for the hikey low-speed expansion header.

Can somebody suggest me in this?