net: phy: add genphy_check_and_restart_aneg()

Add a helper for restarting autonegotiation(), similar to the clause 45
variant.  Use it in __genphy_config_aneg()

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/phy_device.c

@@ -1770,6 +1770,36 @@ int genphy_restart_aneg(struct phy_device *phydev)
 }
 EXPORT_SYMBOL(genphy_restart_aneg);
 
+/**
+ * genphy_check_and_restart_aneg - Enable and restart auto-negotiation
+ * @phydev: target phy_device struct
+ * @restart: whether aneg restart is requested
+ *
+ * Check, and restart auto-negotiation if needed.
+ */
+int genphy_check_and_restart_aneg(struct phy_device *phydev, bool restart)
+{
+	int ret = 0;
+
+	if (!restart) {
+		/* Advertisement hasn't changed, but maybe aneg was never on to
+		 * begin with?  Or maybe phy was isolated?
+		 */
+		ret = phy_read(phydev, MII_BMCR);
+		if (ret < 0)
+			return ret;
+
+		if (!(ret & BMCR_ANENABLE) || (ret & BMCR_ISOLATE))
+			restart = true;
+	}
+
+	if (restart)
+		ret = genphy_restart_aneg(phydev);
+
+	return ret;
+}
+EXPORT_SYMBOL(genphy_check_and_restart_aneg);
+
 /**
  * __genphy_config_aneg - restart auto-negotiation or write BMCR
  * @phydev: target phy_device struct
@@ -1795,23 +1825,7 @@ int __genphy_config_aneg(struct phy_device *phydev, bool changed)
 	else if (err)
 		changed = true;
 
-	if (!changed) {
-		/* Advertisement hasn't changed, but maybe aneg was never on to
-		 * begin with?  Or maybe phy was isolated?
-		 */
-		int ctl = phy_read(phydev, MII_BMCR);
-
-		if (ctl < 0)
-			return ctl;
-
-		if (!(ctl & BMCR_ANENABLE) || (ctl & BMCR_ISOLATE))
-			changed = true; /* do restart aneg */
-	}
-
-	/* Only restart aneg if we are advertising something different
-	 * than we were before.
-	 */
-	return changed ? genphy_restart_aneg(phydev) : 0;
+	return genphy_check_and_restart_aneg(phydev, changed);
 }
 EXPORT_SYMBOL(__genphy_config_aneg);
 

include/linux/phy.h

@@ -1094,6 +1094,7 @@ void phy_attached_info(struct phy_device *phydev);
 int genphy_read_abilities(struct phy_device *phydev);
 int genphy_setup_forced(struct phy_device *phydev);
 int genphy_restart_aneg(struct phy_device *phydev);
+int genphy_check_and_restart_aneg(struct phy_device *phydev, bool restart);
 int genphy_config_eee_advert(struct phy_device *phydev);
 int __genphy_config_aneg(struct phy_device *phydev, bool changed);
 int genphy_aneg_done(struct phy_device *phydev);