ME4000_AO_CTRL_REG
tmp = inl(dev->iobase + ME4000_AO_CTRL_REG(chan));
outl(tmp, dev->iobase + ME4000_AO_CTRL_REG(chan));
outl(0x0, dev->iobase + ME4000_AO_CTRL_REG(chan));
outl(val, dev->iobase + ME4000_AO_CTRL_REG(chan));