参照元†
- struct snd_card *card
- char *id
- int device
- struct snd_hwdep **rhwdep
返り値†
/**
* snd_hwdep_new - create a new hwdep instance
* @card: the card instance
* @id: the id string
* @device: the device index (zero-based)
* @rhwdep: the pointer to store the new hwdep instance
*
* Creates a new hwdep instance with the given index on the card.
* The callbacks (hwdep->ops) must be set on the returned instance
* after this call manually by the caller.
*
* Returns zero if successful, or a negative error code on failure.
*/
int snd_hwdep_new(struct snd_card *card, char *id, int device,
struct snd_hwdep **rhwdep)
{
struct snd_hwdep *hwdep;
int err;
static struct snd_device_ops ops = {
.dev_free = snd_hwdep_dev_free,
.dev_register = snd_hwdep_dev_register,
.dev_disconnect = snd_hwdep_dev_disconnect,
};
if (snd_BUG_ON(!card))
return -ENXIO;
if (rhwdep)
*rhwdep = NULL;
hwdep = kzalloc(sizeof(*hwdep), GFP_KERNEL);
if (hwdep == NULL) {
snd_printk(KERN_ERR "hwdep: cannot allocate\n");
return -ENOMEM;
}
hwdep->card = card;
hwdep->device = device;
if (id)
strlcpy(hwdep->id, id, sizeof(hwdep->id));
#ifdef CONFIG_SND_OSSEMUL
hwdep->oss_type = -1;
#endif
if ((err = snd_device_new(card, SNDRV_DEV_HWDEP, hwdep, &ops)) < 0) {
snd_hwdep_free(hwdep);
return err;
}
init_waitqueue_head(&hwdep->open_wait);
mutex_init(&hwdep->open_mutex);
if (rhwdep)
*rhwdep = hwdep;
return 0;
}
コメント†