mmc_of_find_child_device
card->dev.of_node = mmc_of_find_child_device(card->host, 0);
struct device_node *mmc_of_find_child_device(struct mmc_host *host,
np = mmc_of_find_child_device(card->host, 0);
func->dev.of_node = mmc_of_find_child_device(host, func->num);