to_ulpi_dev
struct ulpi *ulpi = to_ulpi_dev(dev);
ret = ulpi_write(to_ulpi_dev(dev), reg, val);
ret = ulpi_read(to_ulpi_dev(dev), reg);
struct ulpi *ulpi = to_ulpi_dev(dev);
kfree(to_ulpi_dev(dev));
struct ulpi *ulpi = to_ulpi_dev(dev);
const struct ulpi *ulpi = to_ulpi_dev(dev);
return drv->probe(to_ulpi_dev(dev));
drv->remove(to_ulpi_dev(dev));