[PATCH 4.9 19/28] net: phy: fix flag masking in __set_phy_supported

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Heiner Kallweit <hkallweit1@gmail.com>

[ Upstream commit df8ed346d4a806a6eef2db5924285e839604b3f9 ]

Currently also the pause flags are removed from phydev->supported because
they're not included in PHY_DEFAULT_FEATURES. I don't think this is
intended, especially when considering that this function can be called
via phy_set_max_speed() anywhere in a driver. Change the masking to mask
out only the values we're going to change. In addition remove the
misleading comment, job of this small function is just to adjust the
supported and advertised speeds.

Fixes: f3a6bd393c2c ("phylib: Add phy_set_max_speed helper")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/phy/phy_device.c |    7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1579,11 +1579,8 @@ static int gen10g_resume(struct phy_devi
 
 static int __set_phy_supported(struct phy_device *phydev, u32 max_speed)
 {
-	/* The default values for phydev->supported are provided by the PHY
-	 * driver "features" member, we want to reset to sane defaults first
-	 * before supporting higher speeds.
-	 */
-	phydev->supported &= PHY_DEFAULT_FEATURES;
+	phydev->supported &= ~(PHY_1000BT_FEATURES | PHY_100BT_FEATURES |
+			       PHY_10BT_FEATURES);
 
 	switch (max_speed) {
 	default: