net: phylink: simplify fixed-link case for ksettings_set method

For fixed links, we only allow the current settings, so this should be
a matter of merely rejecting an attempt to change the settings.  If the
settings agree, then there is nothing more we need to do.

Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 6cb9ca7..452d509 100644 (file)
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -1360,22 +1360,31 @@ int phylink_ethtool_ksettings_set(struct phylink *pl,
                if (!s)
                        return -EINVAL;
 
-               /* If we have a fixed link (as specified by firmware), refuse
-                * to change link parameters.
+               /* If we have a fixed link, refuse to change link parameters.
+                * If the link parameters match, accept them but do nothing.
                 */
-               if (pl->cur_link_an_mode == MLO_AN_FIXED &&
-                   (s->speed != pl->link_config.speed ||
-                    s->duplex != pl->link_config.duplex))
-                       return -EINVAL;
+               if (pl->cur_link_an_mode == MLO_AN_FIXED) {
+                       if (s->speed != pl->link_config.speed ||
+                           s->duplex != pl->link_config.duplex)
+                               return -EINVAL;
+                       return 0;
+               }
 
                config.speed = s->speed;
                config.duplex = s->duplex;
                break;
 
        case AUTONEG_ENABLE:
-               /* If we have a fixed link, refuse to enable autonegotiation */
-               if (pl->cur_link_an_mode == MLO_AN_FIXED)
-                       return -EINVAL;
+               /* If we have a fixed link, allow autonegotiation (since that
+                * is our default case) but do not allow the advertisement to
+                * be changed. If the advertisement matches, simply return.
+                */
+               if (pl->cur_link_an_mode == MLO_AN_FIXED) {
+                       if (!linkmode_equal(config.advertising,
+                                           pl->link_config.advertising))
+                               return -EINVAL;
+                       return 0;
+               }
 
                config.speed = SPEED_UNKNOWN;
                config.duplex = DUPLEX_UNKNOWN;
@@ -1385,8 +1394,8 @@ int phylink_ethtool_ksettings_set(struct phylink *pl,
                return -EINVAL;
        }
 
-       /* For a fixed link, this isn't able to change any parameters,
-        * which just leaves inband mode.
+       /* We have ruled out the case with a PHY attached, and the
+        * fixed-link cases.  All that is left are in-band links.
         */
        if (phylink_validate(pl, support, &config))
                return -EINVAL;