-extern int snd_ad1816a_pcm(ad1816a_t *chip, int device, snd_pcm_t **rpcm);
-extern int snd_ad1816a_mixer(ad1816a_t *chip);
+extern int snd_ad1816a_pcm(struct snd_ad1816a *chip, int device, struct snd_pcm **rpcm);
+extern int snd_ad1816a_mixer(struct snd_ad1816a *chip);