[PATCH net-next] net: phy: add flag PHY_QUIRK_NO_ESTATEN

[Heiner Kallweit]

We have a Xilinx GBit PHY that doesn't have BMSR_ESTATEN set
(what violates the Clause 22 standard). Instead of having the PHY
driver to implement almost identical copies of few generic functions
let's add a flag for this quirk to phylib.

Signed-off-by: Heiner Kallweit <hkallwe...@gmail.com>
---
 drivers/net/phy/phy_device.c |  6 +++---
 include/linux/phy.h          | 16 +++++++++++++---
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 2c879ba01..7593ebebf 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1595,7 +1595,7 @@ static int genphy_config_advert(struct phy_device *phydev)
         * 1000Mbits/sec capable PHYs shall have the BMSR_ESTATEN bit set to a
         * logical 1.
         */
-       if (!(bmsr & BMSR_ESTATEN))
+       if (!(bmsr & BMSR_ESTATEN) && !phy_quirk_no_estaten(phydev))
                return changed;
 
        /* Configure gigabit if it's supported */
@@ -1919,7 +1919,7 @@ int genphy_config_init(struct phy_device *phydev)
        if (val & BMSR_10HALF)
                linkmode_set_bit(ETHTOOL_LINK_MODE_10baseT_Half_BIT, features);
 
-       if (val & BMSR_ESTATEN) {
+       if (val & BMSR_ESTATEN || phy_quirk_no_estaten(phydev)) {
                val = phy_read(phydev, MII_ESTATUS);
                if (val < 0)
                        return val;
@@ -1972,7 +1972,7 @@ int genphy_read_abilities(struct phy_device *phydev)
        linkmode_mod_bit(ETHTOOL_LINK_MODE_10baseT_Half_BIT, phydev->supported,
                         val & BMSR_10HALF);
 
-       if (val & BMSR_ESTATEN) {
+       if (val & BMSR_ESTATEN || phy_quirk_no_estaten(phydev)) {
                val = phy_read(phydev, MII_ESTATUS);
                if (val < 0)
                        return val;
diff --git a/include/linux/phy.h b/include/linux/phy.h
index dc4b51060..b2ffd82b1 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -73,9 +73,10 @@ extern const int phy_10gbit_features_array[1];
 #define PHY_POLL               -1
 #define PHY_IGNORE_INTERRUPT   -2
 
-#define PHY_IS_INTERNAL                0x00000001
-#define PHY_RST_AFTER_CLK_EN   0x00000002
-#define MDIO_DEVICE_IS_PHY     0x80000000
+#define PHY_IS_INTERNAL                BIT(0)
+#define PHY_RST_AFTER_CLK_EN   BIT(1)
+#define PHY_QUIRK_NO_ESTATEN   BIT(2)
+#define MDIO_DEVICE_IS_PHY     BIT(31)
 
 /* Interface Mode definitions */
 typedef enum {
@@ -677,6 +678,15 @@ size_t phy_speeds(unsigned int *speeds, size_t size,
 void of_set_phy_supported(struct phy_device *phydev);
 void of_set_phy_eee_broken(struct phy_device *phydev);
 
+/**
+ * phy_quirk_no_estaten - Helper to check for flag PHY_QUIRK_NO_ESTATEN
+ * @phydev: The phy_device struct
+ */
+static inline bool phy_quirk_no_estaten(struct phy_device *phydev)
+{
+       return phydev->drv && phydev->drv->flags & PHY_QUIRK_NO_ESTATEN;
+}
+
 /**
  * phy_is_started - Convenience function to check whether PHY is started
  * @phydev: The phy_device struct
-- 
2.21.0