Man page 9 : snd_pcm_new_internal

snd_pcm_new_internal - create a new internal PCM instance

int snd_pcm_new_internal(struct snd_card *  card , const char *  id , int  device , int  playback_count , int  capture_count , struct snd_pcm **  rpcm );

card
    the card instance

id
    the id string

device
    the device index (zero based - shared with normal PCMs)

playback_count
    the number of substreams for playback

capture_count
    the number of substreams for capture

rpcm
    the pointer to store the new pcm instance

Creates a new internal PCM instance with no userspace device or procfs entries. This is used by ASoC Back End PCMs in order to create a PCM that will only be used internally by kernel drivers. i.e. it cannot be opened by userspace. It provides existing ASoC components drivers with a substream and access to any private data.

The pcm operators have to be set afterwards to the new instance via snd_pcm_set_ops.

Zero if successful, or a negative error code on failure.