access davince_pcm.c from userspace

I want to access functions in davince_pcm.c from usersp
In sound/soc/davinci/davinvi_pcm.c have struct:

static struct snd_pcm_ops davinci_pcm_ops = {
.open = davinci_pcm_open,
.close = davinci_pcm_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = davinci_pcm_hw_params,
.hw_free = davinci_pcm_hw_free,
.prepare = davinci_pcm_prepare,
.trigger = davinci_pcm_trigger,
.pointer = davinci_pcm_pointer,
.mmap = davinci_pcm_mmap,

But i dont know where i call there function from userspace, example gpio driver, i can access in /sys/class/gpio
Please help me, i’m sorry if my english not well, :slight_smile: