net: ks8851: Register MDIO bus and the internal PHY

The KS8851 has a reduced internal PHY, which is accessible through its
registers at offset 0xe4. The PHY is compatible with KS886x PHY present
in Micrel switches, except the PHY ID Low/High registers are swapped.
Register MDIO bus so this PHY can be detected and probed by phylib.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Cc: Lukas Wunner <lukas@wunner.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/micrel/ks8851.h b/drivers/net/ethernet/micrel/ks8851.h
index 2b319e4..e2eb0ca 100644 (file)
--- a/drivers/net/ethernet/micrel/ks8851.h
+++ b/drivers/net/ethernet/micrel/ks8851.h
@@ -358,6 +358,7 @@ union ks8851_tx_hdr {
  * @vdd_reg:   Optional regulator supplying the chip
  * @vdd_io: Optional digital power supply for IO
  * @gpio: Optional reset_n gpio
+ * @mii_bus: Pointer to MII bus structure
  * @lock: Bus access lock callback
  * @unlock: Bus access unlock callback
  * @rdreg16: 16bit register read callback
@@ -403,6 +404,7 @@ struct ks8851_net {
        struct regulator        *vdd_reg;
        struct regulator        *vdd_io;
        int                     gpio;
+       struct mii_bus          *mii_bus;
 
        void                    (*lock)(struct ks8851_net *ks,
                                        unsigned long *flags);

diff --git a/drivers/net/ethernet/micrel/ks8851_common.c b/drivers/net/ethernet/micrel/ks8851_common.c
index 6fc7483..058fd99 100644 (file)
--- a/drivers/net/ethernet/micrel/ks8851_common.c
+++ b/drivers/net/ethernet/micrel/ks8851_common.c
@@ -23,6 +23,7 @@
 
 #include <linux/gpio.h>
 #include <linux/of_gpio.h>
+#include <linux/of_mdio.h>
 #include <linux/of_net.h>
 
 #include "ks8851.h"
@@ -932,7 +933,25 @@ static int ks8851_phy_reg(int reg)
                return KS_P1ANLPR;
        }
 
-       return 0x0;
+       return -EOPNOTSUPP;
+}
+
+static int ks8851_phy_read_common(struct net_device *dev, int phy_addr, int reg)
+{
+       struct ks8851_net *ks = netdev_priv(dev);
+       unsigned long flags;
+       int result;
+       int ksreg;
+
+       ksreg = ks8851_phy_reg(reg);
+       if (ksreg < 0)
+               return ksreg;
+
+       ks8851_lock(ks, &flags);
+       result = ks8851_rdreg16(ks, ksreg);
+       ks8851_unlock(ks, &flags);
+
+       return result;
 }
 
 /**
@@ -952,20 +971,13 @@ static int ks8851_phy_reg(int reg)
  */
 static int ks8851_phy_read(struct net_device *dev, int phy_addr, int reg)
 {
-       struct ks8851_net *ks = netdev_priv(dev);
-       unsigned long flags;
-       int ksreg;
-       int result;
+       int ret;
 
-       ksreg = ks8851_phy_reg(reg);
-       if (!ksreg)
+       ret = ks8851_phy_read_common(dev, phy_addr, reg);
+       if (ret < 0)
                return 0x0;     /* no error return allowed, so use zero */
 
-       ks8851_lock(ks, &flags);
-       result = ks8851_rdreg16(ks, ksreg);
-       ks8851_unlock(ks, &flags);
-
-       return result;
+       return ret;
 }
 
 static void ks8851_phy_write(struct net_device *dev,
@@ -976,13 +988,37 @@ static void ks8851_phy_write(struct net_device *dev,
        int ksreg;
 
        ksreg = ks8851_phy_reg(reg);
-       if (ksreg) {
+       if (ksreg >= 0) {
                ks8851_lock(ks, &flags);
                ks8851_wrreg16(ks, ksreg, value);
                ks8851_unlock(ks, &flags);
        }
 }
 
+static int ks8851_mdio_read(struct mii_bus *bus, int phy_id, int reg)
+{
+       struct ks8851_net *ks = bus->priv;
+
+       if (phy_id != 0)
+               return -EOPNOTSUPP;
+
+       /* KS8851 PHY ID registers are swapped in HW, swap them back. */
+       if (reg == MII_PHYSID1)
+               reg = MII_PHYSID2;
+       else if (reg == MII_PHYSID2)
+               reg = MII_PHYSID1;
+
+       return ks8851_phy_read_common(ks->netdev, phy_id, reg);
+}
+
+static int ks8851_mdio_write(struct mii_bus *bus, int phy_id, int reg, u16 val)
+{
+       struct ks8851_net *ks = bus->priv;
+
+       ks8851_phy_write(ks->netdev, phy_id, reg, val);
+       return 0;
+}
+
 /**
  * ks8851_read_selftest - read the selftest memory info.
  * @ks: The device state
@@ -1046,6 +1082,42 @@ int ks8851_resume(struct device *dev)
 }
 #endif
 
+static int ks8851_register_mdiobus(struct ks8851_net *ks, struct device *dev)
+{
+       struct mii_bus *mii_bus;
+       int ret;
+
+       mii_bus = mdiobus_alloc();
+       if (!mii_bus)
+               return -ENOMEM;
+
+       mii_bus->name = "ks8851_eth_mii";
+       mii_bus->read = ks8851_mdio_read;
+       mii_bus->write = ks8851_mdio_write;
+       mii_bus->priv = ks;
+       mii_bus->parent = dev;
+       mii_bus->phy_mask = ~((u32)BIT(0));
+       snprintf(mii_bus->id, MII_BUS_ID_SIZE, "%s", dev_name(dev));
+
+       ret = mdiobus_register(mii_bus);
+       if (ret)
+               goto err_mdiobus_register;
+
+       ks->mii_bus = mii_bus;
+
+       return 0;
+
+err_mdiobus_register:
+       mdiobus_free(mii_bus);
+       return ret;
+}
+
+static void ks8851_unregister_mdiobus(struct ks8851_net *ks)
+{
+       mdiobus_unregister(ks->mii_bus);
+       mdiobus_free(ks->mii_bus);
+}
+
 int ks8851_probe_common(struct net_device *netdev, struct device *dev,
                        int msg_en)
 {
@@ -1104,6 +1176,8 @@ int ks8851_probe_common(struct net_device *netdev, struct device *dev,
 
        INIT_WORK(&ks->rxctrl_work, ks8851_rxctrl_work);
 
+       SET_NETDEV_DEV(netdev, dev);
+
        /* setup EEPROM state */
        ks->eeprom.data = ks;
        ks->eeprom.width = PCI_EEPROM_WIDTH_93C46;
@@ -1120,6 +1194,10 @@ int ks8851_probe_common(struct net_device *netdev, struct device *dev,
 
        dev_info(dev, "message enable is %d\n", msg_en);
 
+       ret = ks8851_register_mdiobus(ks, dev);
+       if (ret)
+               goto err_mdio;
+
        /* set the default message enable */
        ks->msg_enable = netif_msg_init(msg_en, NETIF_MSG_DRV |
                                                NETIF_MSG_PROBE |
@@ -1128,7 +1206,6 @@ int ks8851_probe_common(struct net_device *netdev, struct device *dev,
        skb_queue_head_init(&ks->txq);
 
        netdev->ethtool_ops = &ks8851_ethtool_ops;
-       SET_NETDEV_DEV(netdev, dev);
 
        dev_set_drvdata(dev, ks);
 
@@ -1156,7 +1233,7 @@ int ks8851_probe_common(struct net_device *netdev, struct device *dev,
        ret = register_netdev(netdev);
        if (ret) {
                dev_err(dev, "failed to register network device\n");
-               goto err_netdev;
+               goto err_id;
        }
 
        netdev_info(netdev, "revision %d, MAC %pM, IRQ %d, %s EEPROM\n",
@@ -1165,8 +1242,9 @@ int ks8851_probe_common(struct net_device *netdev, struct device *dev,
 
        return 0;
 
-err_netdev:
 err_id:
+       ks8851_unregister_mdiobus(ks);
+err_mdio:
        if (gpio_is_valid(gpio))
                gpio_set_value(gpio, 0);
        regulator_disable(ks->vdd_reg);
@@ -1180,6 +1258,8 @@ int ks8851_remove_common(struct device *dev)
 {
        struct ks8851_net *priv = dev_get_drvdata(dev);
 
+       ks8851_unregister_mdiobus(priv);
+
        if (netif_msg_drv(priv))
                dev_info(dev, "remove\n");