SC16IS7XX_SPI_FREQUENCY
#ifndef SC16IS7XX_SPI_FREQUENCY
aprint_normal_dev(sc->sc_dev, "SPI frequency %dMhz", SC16IS7XX_SPI_FREQUENCY);
error = spi_configure(self, sa->sa_handle, SPI_MODE_0, SPI_FREQ_MHz(SC16IS7XX_SPI_FREQUENCY));