net: phy: Do not check Link status when loopback is enabled

While running stmmac selftests I found that in my 1G setup some tests
were failling when running with PHY loopback enabled.

It looks like when loopback is enabled the PHY will report that Link is
down even though there is a valid connection.

As in loopback mode the data will not be sent anywhere we can bypass the
logic of checking if Link is valid thus saving unecessary reads.

Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index 35d29a823af85eee5e526d6d4685588f21d5033f..7c92afd36bbeb98f1f372b67b335f00a0da1772c 100644 (file)
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -525,6 +525,12 @@ static int phy_check_link_status(struct phy_device *phydev)
 
        WARN_ON(!mutex_is_locked(&phydev->lock));
 
+       /* Keep previous state if loopback is enabled because some PHYs
+        * report that Link is Down when loopback is enabled.
+        */
+       if (phydev->loopback_enabled)
+               return 0;
+
        err = phy_read_status(phydev);
        if (err)
                return err;