On Wed, 2019-12-11 at 00:48 +0800, Andrew Lunn wrote: > > +static int mt7531_setup(struct dsa_switch *ds) > > +{ > > + /* Enable PHY power, since phy_device has not yet been created > > + * provided for phy_[read,write]_mmd_indirect is called, we provide > > + * our own mt7531_ind_mmd_phy_[read,write] to complete this > > + * function. > > + */ > > + val = mt7531_ind_mmd_phy_read(priv, 0, PHY_DEV1F, > > + MT7531_PHY_DEV1F_REG_403); > > + val |= MT7531_PHY_EN_BYPASS_MODE; > > + val &= ~MT7531_PHY_POWER_OFF; > > + mt7531_ind_mmd_phy_write(priv, 0, PHY_DEV1F, > > + MT7531_PHY_DEV1F_REG_403, val); > > + > > Is this power to all the PHYs? Or just one? This is an internal circuit that controls the power to all PHYs before Generic MII registers are available. Landen > > Andrew