NPCM_I2CCST_BB
iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST);
iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST);
bus_busy = ioread8(bus->reg + NPCM_I2CCST) & NPCM_I2CCST_BB;
iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST);
iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST);