NPCM_I2CRXF_STS
ioread8(bus->reg + NPCM_I2CRXF_STS));
rx_fifo_sts = ioread8(bus->reg + NPCM_I2CRXF_STS);
val = ioread8(bus->reg + NPCM_I2CRXF_STS);
iowrite8(val, bus->reg + NPCM_I2CRXF_STS);