3.16.72-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Heiner Kallweit <hkallweit1@xxxxxxxxx> commit d29f5aa0bc0c321e1b9e4658a2a7e08e885da52a upstream. So far we effectively clear the BMCR register. Some PHY's can deal with this (e.g. because they reset BMCR to a default as part of a soft-reset) whilst on others this causes issues because e.g. the autoneg bit is cleared. Marvell is an example, see also thread [0]. So let's be a little bit more gentle and leave all bits we're not interested in as-is. This change is needed for PHY drivers to properly deal with the original patch. [0] https://marc.info/?t=155264050700001&r=1&w=2 Fixes: 6e2d85ec0559 ("net: phy: Stop with excessive soft reset") Tested-by: Phil Reid <preid@xxxxxxxxxxxxxxxxx> Tested-by: liweihang <liweihang@xxxxxxxxxxxxx> Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx> Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> [bwh: Backported to 3.16: open-code phy_set_bits()] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -1072,7 +1072,10 @@ int genphy_soft_reset(struct phy_device { int ret; - ret = phy_write(phydev, MII_BMCR, BMCR_RESET); + ret = phy_read(phydev, MII_BMCR); + if (ret < 0) + return ret; + ret = phy_write(phydev, MII_BMCR, ret | BMCR_RESET); if (ret < 0) return ret;