void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
const struct snd_interval *b, struct snd_interval *c);
-int snd_pcm_hw_constraints_init(struct snd_pcm_substream *substream);
-int snd_pcm_hw_constraints_complete(struct snd_pcm_substream *substream);
-
int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime,
snd_pcm_hw_param_t var, u_int32_t mask);