r8169: fix wrong PHY ID issue with RTL8168dp

[ Upstream commit 62bdc8fd1c21d4263ebd18bec57f82532d09249f ]

As reported in [0] at least one RTL8168dp version has problems
establishing a link. This chip version has an integrated RTL8211b PHY,
however the chip seems to report a wrong PHY ID, resulting in a wrong
PHY driver (for Generic Realtek PHY) being loaded.
Work around this issue by adding a hook to r8168dp_2_mdio_read()
for returning the correct PHY ID.

[0] https://bbs.archlinux.org/viewtopic.php?id=246508

Fixes: 242cd9b5866a ("r8169: use phy_resume/phy_suspend")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/ethernet/realtek/r8169.c b/drivers/net/ethernet/realtek/r8169.c
index 0c8b714..4ab87fe 100644 (file)
--- a/drivers/net/ethernet/realtek/r8169.c
+++ b/drivers/net/ethernet/realtek/r8169.c
@@ -1010,6 +1010,10 @@ static int r8168dp_2_mdio_read(struct rtl8169_private *tp, int reg)
 {
        int value;
 
+       /* Work around issue with chip reporting wrong PHY ID */
+       if (reg == MII_PHYSID2)
+               return 0xc912;
+
        r8168dp_2_mdio_start(tp);
 
        value = r8169_mdio_read(tp, reg);