drivers/net/phy/xilinx_gmii2rgmii.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /* Xilinx GMII2RGMII Converter driver
   3  *
   4  * Copyright (C) 2016 Xilinx, Inc.
   5  * Copyright (C) 2016 Andrew Lunn <andrew@lunn.ch>
   6  *
   7  * Author: Andrew Lunn <andrew@lunn.ch>
   8  * Author: Kedareswara rao Appana <appanad@xilinx.com>
   9  *
  10  * Description:
  11  * This driver is developed for Xilinx GMII2RGMII Converter
  12  */
  13 #include <linux/module.h>
  14 #include <linux/kernel.h>
  15 #include <linux/mii.h>
  16 #include <linux/mdio.h>
  17 #include <linux/phy.h>
  18 #include <linux/of_mdio.h>
  19
  20 #define XILINX_GMII2RGMII_REG           0x10
  21 #define XILINX_GMII2RGMII_SPEED_MASK    (BMCR_SPEED1000 | BMCR_SPEED100)
  22
  23 struct gmii2rgmii {
  24         struct phy_device *phy_dev;
  25         struct phy_driver *phy_drv;
  26         struct phy_driver conv_phy_drv;
  27         struct mdio_device *mdio;
  28 };
  29
  30 static void xgmiitorgmii_configure(struct gmii2rgmii *priv, int speed)
  31 {
  32         struct mii_bus *bus = priv->mdio->bus;
  33         int addr = priv->mdio->addr;
  34         u16 val;
  35
  36         val = mdiobus_read(bus, addr, XILINX_GMII2RGMII_REG);
  37         val &= ~XILINX_GMII2RGMII_SPEED_MASK;
  38
  39         if (speed == SPEED_1000)
  40                 val |= BMCR_SPEED1000;
  41         else if (speed == SPEED_100)
  42                 val |= BMCR_SPEED100;
  43         else
  44                 val |= BMCR_SPEED10;
  45
  46         mdiobus_write(bus, addr, XILINX_GMII2RGMII_REG, val);
  47 }
  48
  49 static int xgmiitorgmii_read_status(struct phy_device *phydev)
  50 {
  51         struct gmii2rgmii *priv = mdiodev_get_drvdata(&phydev->mdio);
  52         int err;
  53
  54         if (priv->phy_drv->read_status)
  55                 err = priv->phy_drv->read_status(phydev);
  56         else
  57                 err = genphy_read_status(phydev);
  58         if (err < 0)
  59                 return err;
  60
  61         xgmiitorgmii_configure(priv, phydev->speed);
  62
  63         return 0;
  64 }
  65
  66 static int xgmiitorgmii_set_loopback(struct phy_device *phydev, bool enable)
  67 {
  68         struct gmii2rgmii *priv = mdiodev_get_drvdata(&phydev->mdio);
  69         int err;
  70
  71         if (priv->phy_drv->set_loopback)
  72                 err = priv->phy_drv->set_loopback(phydev, enable);
  73         else
  74                 err = genphy_loopback(phydev, enable);
  75         if (err < 0)
  76                 return err;
  77
  78         xgmiitorgmii_configure(priv, phydev->speed);
  79
  80         return 0;
  81 }
  82
  83 static int xgmiitorgmii_probe(struct mdio_device *mdiodev)
  84 {
  85         struct device *dev = &mdiodev->dev;
  86         struct device_node *np = dev->of_node, *phy_node;
  87         struct gmii2rgmii *priv;
  88
  89         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
  90         if (!priv)
  91                 return -ENOMEM;
  92
  93         phy_node = of_parse_phandle(np, "phy-handle", 0);
  94         if (!phy_node) {
  95                 dev_err(dev, "Couldn't parse phy-handle\n");
  96                 return -ENODEV;
  97         }
  98
  99         priv->phy_dev = of_phy_find_device(phy_node);
 100         of_node_put(phy_node);
 101         if (!priv->phy_dev) {
 102                 dev_info(dev, "Couldn't find phydev\n");
 103                 return -EPROBE_DEFER;
 104         }
 105
 106         if (!priv->phy_dev->drv) {
 107                 dev_info(dev, "Attached phy not ready\n");
 108                 put_device(&priv->phy_dev->mdio.dev);
 109                 return -EPROBE_DEFER;
 110         }
 111
 112         priv->mdio = mdiodev;
 113         priv->phy_drv = priv->phy_dev->drv;
 114         memcpy(&priv->conv_phy_drv, priv->phy_dev->drv,
 115                sizeof(struct phy_driver));
 116         priv->conv_phy_drv.read_status = xgmiitorgmii_read_status;
 117         priv->conv_phy_drv.set_loopback = xgmiitorgmii_set_loopback;
 118         mdiodev_set_drvdata(&priv->phy_dev->mdio, priv);
 119         priv->phy_dev->drv = &priv->conv_phy_drv;
 120
 121         return 0;
 122 }
 123
 124 static const struct of_device_id xgmiitorgmii_of_match[] = {
 125         { .compatible = "xlnx,gmii-to-rgmii-1.0" },
 126         {},
 127 };
 128 MODULE_DEVICE_TABLE(of, xgmiitorgmii_of_match);
 129
 130 static struct mdio_driver xgmiitorgmii_driver = {
 131         .probe  = xgmiitorgmii_probe,
 132         .mdiodrv.driver = {
 133                 .name = "xgmiitorgmii",
 134                 .of_match_table = xgmiitorgmii_of_match,
 135         },
 136 };
 137
 138 mdio_module_driver(xgmiitorgmii_driver);
 139
 140 MODULE_DESCRIPTION("Xilinx GMII2RGMII converter driver");
 141 MODULE_LICENSE("GPL");