SSC_RBUF
readl_relaxed(i2c_dev->base + SSC_RBUF);
rbuf = readl_relaxed(i2c_dev->base + SSC_RBUF) >> 1;
readl_relaxed(i2c_dev->base + SSC_RBUF);
word = readl_relaxed(spi_st->base + SSC_RBUF);
readl_relaxed(spi_st->base + SSC_RBUF);
readl_relaxed(spi_st->base + SSC_RBUF);