CONFIG_SND_SOC_AD1938 (not configurable)

modulename: snd-soc-ad1938.ko

configname: CONFIG_SND_SOC_AD1938

Linux Kernel Configuration
└─>Device Drivers
└─>Sound card support
└─>Advanced Linux Sound Architecture
└─>ALSA for SoC audio support
└─>SND_SOC_AD1938
In linux kernel since version 2.6.32 (release Date: 2009-12-02)  
source code:
sound/soc//codecs/