net: phy: Add support for asking the PHY its abilities

Add support for runtime determination of what the PHY supports, by
adding a new function to the phy driver. The get_features call should
set the phydev->supported member with the features the PHY supports.
It is only called if phydrv->features is NULL.

This requires minor changes to pause. The PHY driver should not set
pause abilities, except for when it has odd cause capabilities, e.g.
pause cannot be disabled. With this change, phydev->supported already
contains the drivers abilities, including pause. So rather than
considering phydrv->features, look at the phydev->supported, and
enable pause if neither of the pause bits are already set.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
[hkallweit1@gmail.com: fixed small checkpatch complaint in one comment]
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 92b7a71df0ac87db88afed40c28ec5340bc55400..8573d17ece0ff35579ee26da5f6e7cf3810a7012 100644 (file)
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -2236,7 +2236,14 @@ static int phy_probe(struct device *dev)
         * a controller will attach, and may modify one
         * or both of these values
         */
-       linkmode_copy(phydev->supported, phydrv->features);
+       if (phydrv->features) {
+               linkmode_copy(phydev->supported, phydrv->features);
+       } else {
+               err = phydrv->get_features(phydev);
+               if (err)
+                       goto out;
+       }
+
        of_set_phy_supported(phydev);
        linkmode_copy(phydev->advertising, phydev->supported);
 
@@ -2256,20 +2263,8 @@ static int phy_probe(struct device *dev)
         * (e.g. hardware erratum) where the driver wants to set only one
         * of these bits.
         */
-       if (test_bit(ETHTOOL_LINK_MODE_Pause_BIT, phydrv->features) ||
-           test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, phydrv->features)) {
-               linkmode_clear_bit(ETHTOOL_LINK_MODE_Pause_BIT,
-                                  phydev->supported);
-               linkmode_clear_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
-                                  phydev->supported);
-               if (test_bit(ETHTOOL_LINK_MODE_Pause_BIT, phydrv->features))
-                       linkmode_set_bit(ETHTOOL_LINK_MODE_Pause_BIT,
-                                        phydev->supported);
-               if (test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
-                            phydrv->features))
-                       linkmode_set_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
-                                        phydev->supported);
-       } else {
+       if (!test_bit(ETHTOOL_LINK_MODE_Pause_BIT, phydev->supported) &&
+           !test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, phydev->supported)) {
                linkmode_set_bit(ETHTOOL_LINK_MODE_Pause_BIT,
                                 phydev->supported);
                linkmode_set_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
@@ -2315,7 +2310,11 @@ int phy_driver_register(struct phy_driver *new_driver, struct module *owner)
 {
        int retval;
 
-       if (WARN_ON(!new_driver->features)) {
+       /* Either the features are hard coded, or dynamically
+        * determine. It cannot be both or neither
+        */
+       if (WARN_ON((!new_driver->features && !new_driver->get_features) ||
+                   (new_driver->features && new_driver->get_features))) {
                pr_err("%s: Driver features are missing\n", new_driver->name);
                return -EINVAL;
        }

diff --git a/include/linux/phy.h b/include/linux/phy.h
index f41bf651f6a0c9f8c0dc755e4a58d467428a97df..d2ffae992e4ac88690d629e0e8e0a82b97faad02 100644 (file)
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -502,6 +502,12 @@ struct phy_driver {
         */
        int (*probe)(struct phy_device *phydev);
 
+       /*
+        * Probe the hardware to determine what abilities it has.
+        * Should only set phydev->supported.
+        */
+       int (*get_features)(struct phy_device *phydev);
+
        /* PHY Power Management */
        int (*suspend)(struct phy_device *phydev);
        int (*resume)(struct phy_device *phydev);