net: phy: meson-gxl: Add generic dummy stubs for MMD register access

commit afc2336f89dc0fc0ef25b92366814524b0fd90fb upstream.

The Meson G12A Internal PHY does not support standard IEEE MMD extended
register access, therefore add generic dummy stubs to fail the read and
write MMD calls. This is necessary to prevent the core PHY code from
erroneously believing that EEE is supported by this PHY even though this
PHY does not support EEE, as MMD register access returns all FFFFs.

Fixes: 5c3407abb338 ("net: phy: meson-gxl: add g12a support")
Reviewed-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Chris Healy <healych@amazon.com>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20230130231402.471493-1-cphealy@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/phy/meson-gxl.c b/drivers/net/phy/meson-gxl.c
index b6436e7dabbc666ef06d0c1d6c98fe13f2bd14ec..75546829b86be8882abd544101fc100cfac5bcfa 100644 (file)
--- a/drivers/net/phy/meson-gxl.c
+++ b/drivers/net/phy/meson-gxl.c
@@ -258,6 +258,8 @@ static struct phy_driver meson_gxl_phy[] = {
                .config_intr    = meson_gxl_config_intr,
                .suspend        = genphy_suspend,
                .resume         = genphy_resume,
+               .read_mmd       = genphy_read_mmd_unsupported,
+               .write_mmd      = genphy_write_mmd_unsupported,
        },
 };