BCM2835 ALSA driver

modulename: snd-bcm2835.ko

configname: CONFIG_SND_BCM2835

Linux Kernel Configuration
└─>Device Drivers
└─>Staging drivers
└─>Advanced Linux Sound Architecture
└─>BCM2835 ALSA driver
In linux kernel since version 3.10 (release Date: 2013-06-30)  
Say Y or M if you want to support BCM2835 Alsa pcm card driver

source code:
drivers/staging/bcm2835-audio/