E1000_CTRL_MDIO
if(data & mask) ctrl |= E1000_CTRL_MDIO;
else ctrl &= ~E1000_CTRL_MDIO;
ctrl &= ~E1000_CTRL_MDIO;
if(ctrl & E1000_CTRL_MDIO) data |= 1;
ctrl |= E1000_CTRL_MDIO;
ctrl &= ~E1000_CTRL_MDIO;
ctrl &= ~E1000_CTRL_MDIO;
if (ctrl & E1000_CTRL_MDIO)