net: mdio: i2c: Separate C22 and C45 transactions

The MDIO over I2C bus driver can perform both C22 and C45 transfers.
Create separate functions for each and register the C45 versions using
the new API calls.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/mdio/mdio-i2c.c

@@ -30,7 +30,8 @@ static unsigned int i2c_mii_phy_addr(int phy_id)
 	return phy_id + 0x40;
 }
 
-static int i2c_mii_read_default(struct mii_bus *bus, int phy_id, int reg)
+static int i2c_mii_read_default_c45(struct mii_bus *bus, int phy_id, int devad,
+				    int reg)
 {
 	struct i2c_adapter *i2c = bus->priv;
 	struct i2c_msg msgs[2];
@@ -41,8 +42,8 @@ static int i2c_mii_read_default(struct mii_bus *bus, int phy_id, int reg)
 		return 0xffff;
 
 	p = addr;
-	if (reg & MII_ADDR_C45) {
-		*p++ = 0x20 | ((reg >> 16) & 31);
+	if (devad >= 0) {
+		*p++ = 0x20 | devad;
 		*p++ = reg >> 8;
 	}
 	*p++ = reg;
@@ -64,8 +65,8 @@ static int i2c_mii_read_default(struct mii_bus *bus, int phy_id, int reg)
 	return data[0] << 8 | data[1];
 }
 
-static int i2c_mii_write_default(struct mii_bus *bus, int phy_id, int reg,
-				 u16 val)
+static int i2c_mii_write_default_c45(struct mii_bus *bus, int phy_id,
+				     int devad, int reg, u16 val)
 {
 	struct i2c_adapter *i2c = bus->priv;
 	struct i2c_msg msg;
@@ -76,8 +77,8 @@ static int i2c_mii_write_default(struct mii_bus *bus, int phy_id, int reg,
 		return 0;
 
 	p = data;
-	if (reg & MII_ADDR_C45) {
-		*p++ = (reg >> 16) & 31;
+	if (devad >= 0) {
+		*p++ = devad;
 		*p++ = reg >> 8;
 	}
 	*p++ = reg;
@@ -94,6 +95,17 @@ static int i2c_mii_write_default(struct mii_bus *bus, int phy_id, int reg,
 	return ret < 0 ? ret : 0;
 }
 
+static int i2c_mii_read_default_c22(struct mii_bus *bus, int phy_id, int reg)
+{
+	return i2c_mii_read_default_c45(bus, phy_id, -1, reg);
+}
+
+static int i2c_mii_write_default_c22(struct mii_bus *bus, int phy_id, int reg,
+				     u16 val)
+{
+	return i2c_mii_write_default_c45(bus, phy_id, -1, reg, val);
+}
+
 /* RollBall SFPs do not access internal PHY via I2C address 0x56, but
  * instead via address 0x51, when SFP page is set to 0x03 and password to
  * 0xffffffff.
@@ -403,8 +415,10 @@ struct mii_bus *mdio_i2c_alloc(struct device *parent, struct i2c_adapter *i2c,
 		mii->write = i2c_mii_write_rollball;
 		break;
 	default:
-		mii->read = i2c_mii_read_default;
-		mii->write = i2c_mii_write_default;
+		mii->read = i2c_mii_read_default_c22;
+		mii->write = i2c_mii_write_default_c22;
+		mii->read_c45 = i2c_mii_read_default_c45;
+		mii->write_c45 = i2c_mii_write_default_c45;
 		break;
 	}