net: phy: broadcom: add helper to write/read RDB registers

RDB (Register Data Base) registers are used on newer Broadcom PHYs. Add
helper to read, write and modify these registers.
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/bcm-phy-lib.c

@@ -155,6 +155,86 @@ int bcm_phy_write_shadow(struct phy_device *phydev, u16 shadow,
 }
 EXPORT_SYMBOL_GPL(bcm_phy_write_shadow);
 
+int __bcm_phy_read_rdb(struct phy_device *phydev, u16 rdb)
+{
+	int val;
+
+	val = __phy_write(phydev, MII_BCM54XX_RDB_ADDR, rdb);
+	if (val < 0)
+		return val;
+
+	return __phy_read(phydev, MII_BCM54XX_RDB_DATA);
+}
+EXPORT_SYMBOL_GPL(__bcm_phy_read_rdb);
+
+int bcm_phy_read_rdb(struct phy_device *phydev, u16 rdb)
+{
+	int ret;
+
+	phy_lock_mdio_bus(phydev);
+	ret = __bcm_phy_read_rdb(phydev, rdb);
+	phy_unlock_mdio_bus(phydev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(bcm_phy_read_rdb);
+
+int __bcm_phy_write_rdb(struct phy_device *phydev, u16 rdb, u16 val)
+{
+	int ret;
+
+	ret = __phy_write(phydev, MII_BCM54XX_RDB_ADDR, rdb);
+	if (ret < 0)
+		return ret;
+
+	return __phy_write(phydev, MII_BCM54XX_RDB_DATA, val);
+}
+EXPORT_SYMBOL_GPL(__bcm_phy_write_rdb);
+
+int bcm_phy_write_rdb(struct phy_device *phydev, u16 rdb, u16 val)
+{
+	int ret;
+
+	phy_lock_mdio_bus(phydev);
+	ret = __bcm_phy_write_rdb(phydev, rdb, val);
+	phy_unlock_mdio_bus(phydev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(bcm_phy_write_rdb);
+
+int __bcm_phy_modify_rdb(struct phy_device *phydev, u16 rdb, u16 mask, u16 set)
+{
+	int new, ret;
+
+	ret = __phy_write(phydev, MII_BCM54XX_RDB_ADDR, rdb);
+	if (ret < 0)
+		return ret;
+
+	ret = __phy_read(phydev, MII_BCM54XX_RDB_DATA);
+	if (ret < 0)
+		return ret;
+
+	new = (ret & ~mask) | set;
+	if (new == ret)
+		return 0;
+
+	return __phy_write(phydev, MII_BCM54XX_RDB_DATA, new);
+}
+EXPORT_SYMBOL_GPL(__bcm_phy_modify_rdb);
+
+int bcm_phy_modify_rdb(struct phy_device *phydev, u16 rdb, u16 mask, u16 set)
+{
+	int ret;
+
+	phy_lock_mdio_bus(phydev);
+	ret = __bcm_phy_modify_rdb(phydev, rdb, mask, set);
+	phy_unlock_mdio_bus(phydev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(bcm_phy_modify_rdb);
+
 int bcm_phy_enable_apd(struct phy_device *phydev, bool dll_pwr_down)
 {
 	int val;

drivers/net/phy/bcm-phy-lib.h

@@ -48,6 +48,15 @@ int bcm_phy_write_shadow(struct phy_device *phydev, u16 shadow,
 			 u16 val);
 int bcm_phy_read_shadow(struct phy_device *phydev, u16 shadow);
 
+int __bcm_phy_write_rdb(struct phy_device *phydev, u16 rdb, u16 val);
+int bcm_phy_write_rdb(struct phy_device *phydev, u16 rdb, u16 val);
+int __bcm_phy_read_rdb(struct phy_device *phydev, u16 rdb);
+int bcm_phy_read_rdb(struct phy_device *phydev, u16 rdb);
+int __bcm_phy_modify_rdb(struct phy_device *phydev, u16 rdb, u16 mask,
+			 u16 set);
+int bcm_phy_modify_rdb(struct phy_device *phydev, u16 rdb, u16 mask,
+		       u16 set);
+
 int bcm_phy_ack_intr(struct phy_device *phydev);
 int bcm_phy_config_intr(struct phy_device *phydev);
 

include/linux/brcmphy.h

@@ -115,6 +115,9 @@
 #define MII_BCM54XX_SHD_VAL(x)	((x & 0x1f) << 10)
 #define MII_BCM54XX_SHD_DATA(x)	((x & 0x3ff) << 0)
 
+#define MII_BCM54XX_RDB_ADDR	0x1e
+#define MII_BCM54XX_RDB_DATA	0x1f
+
 /*
  * AUXILIARY CONTROL SHADOW ACCESS REGISTERS.  (PHY REG 0x18)
  */