From: Kevin Hao <haokexin@xxxxxxxxx> [ Upstream commit 5df7af85ecd88e8b5f1f31d6456c3cf38a8bbdda ] For some phy devices, even though they don't support the MMD extended register access, it does have some side effect if we are trying to read/write the MMD registers via indirect method. So introduce general dummy stubs for MMD register access which these devices can use to avoid such side effect. Fixes: b6b5e8a69118 ("gianfar: Disable EEE autoneg by default") Signed-off-by: Kevin Hao <haokexin@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/phy/phy_device.c | 17 +++++++++++++++++ include/linux/phy.h | 4 ++++ 2 files changed, 21 insertions(+) diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index a174d05a9752..fe76e2c4022a 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -1641,6 +1641,23 @@ int genphy_config_init(struct phy_device *phydev) } EXPORT_SYMBOL(genphy_config_init); +/* This is used for the phy device which doesn't support the MMD extended + * register access, but it does have side effect when we are trying to access + * the MMD register via indirect method. + */ +int genphy_read_mmd_unsupported(struct phy_device *phdev, int devad, u16 regnum) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(genphy_read_mmd_unsupported); + +int genphy_write_mmd_unsupported(struct phy_device *phdev, int devnum, + u16 regnum, u16 val) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL(genphy_write_mmd_unsupported); + int genphy_suspend(struct phy_device *phydev) { int value; diff --git a/include/linux/phy.h b/include/linux/phy.h index dca9e926b88f..efc04c2d92c9 100644 --- a/include/linux/phy.h +++ b/include/linux/phy.h @@ -879,6 +879,10 @@ static inline int genphy_no_soft_reset(struct phy_device *phydev) { return 0; } +int genphy_read_mmd_unsupported(struct phy_device *phdev, int devad, + u16 regnum); +int genphy_write_mmd_unsupported(struct phy_device *phdev, int devnum, + u16 regnum, u16 val); /* Clause 45 PHY */ int genphy_c45_restart_aneg(struct phy_device *phydev); -- 2.17.1