drivers/net/phy/xilinx_gmii2rgmii.c

   1 /* Xilinx GMII2RGMII Converter driver
   2  *
   3  * Copyright (C) 2016 Xilinx, Inc.
   4  * Copyright (C) 2016 Andrew Lunn <andrew@lunn.ch>
   5  *
   6  * Author: Andrew Lunn <andrew@lunn.ch>
   7  * Author: Kedareswara rao Appana <appanad@xilinx.com>
   8  *
   9  * Description:
  10  * This driver is developed for Xilinx GMII2RGMII Converter
  11  *
  12  * This program is free software: you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation, either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  */
  22 #include <linux/module.h>
  23 #include <linux/kernel.h>
  24 #include <linux/mii.h>
  25 #include <linux/mdio.h>
  26 #include <linux/phy.h>
  27 #include <linux/of_mdio.h>
  28
  29 #define XILINX_GMII2RGMII_REG           0x10
  30 #define XILINX_GMII2RGMII_SPEED_MASK    (BMCR_SPEED1000 | BMCR_SPEED100)
  31
  32 struct gmii2rgmii {
  33         struct phy_device *phy_dev;
  34         struct phy_driver *phy_drv;
  35         struct phy_driver conv_phy_drv;
  36         int addr;
  37 };
  38
  39 static int xgmiitorgmii_read_status(struct phy_device *phydev)
  40 {
  41         struct gmii2rgmii *priv = phydev->priv;
  42         u16 val = 0;
  43         int err;
  44
  45         err = priv->phy_drv->read_status(phydev);
  46         if (err < 0)
  47                 return err;
  48
  49         val = mdiobus_read(phydev->mdio.bus, priv->addr, XILINX_GMII2RGMII_REG);
  50         val &= ~XILINX_GMII2RGMII_SPEED_MASK;
  51
  52         if (phydev->speed == SPEED_1000)
  53                 val |= BMCR_SPEED1000;
  54         else if (phydev->speed == SPEED_100)
  55                 val |= BMCR_SPEED100;
  56         else
  57                 val |= BMCR_SPEED10;
  58
  59         mdiobus_write(phydev->mdio.bus, priv->addr, XILINX_GMII2RGMII_REG, val);
  60
  61         return 0;
  62 }
  63
  64 static int xgmiitorgmii_probe(struct mdio_device *mdiodev)
  65 {
  66         struct device *dev = &mdiodev->dev;
  67         struct device_node *np = dev->of_node, *phy_node;
  68         struct gmii2rgmii *priv;
  69
  70         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
  71         if (!priv)
  72                 return -ENOMEM;
  73
  74         phy_node = of_parse_phandle(np, "phy-handle", 0);
  75         if (!phy_node) {
  76                 dev_err(dev, "Couldn't parse phy-handle\n");
  77                 return -ENODEV;
  78         }
  79
  80         priv->phy_dev = of_phy_find_device(phy_node);
  81         of_node_put(phy_node);
  82         if (!priv->phy_dev) {
  83                 dev_info(dev, "Couldn't find phydev\n");
  84                 return -EPROBE_DEFER;
  85         }
  86
  87         priv->addr = mdiodev->addr;
  88         priv->phy_drv = priv->phy_dev->drv;
  89         memcpy(&priv->conv_phy_drv, priv->phy_dev->drv,
  90                sizeof(struct phy_driver));
  91         priv->conv_phy_drv.read_status = xgmiitorgmii_read_status;
  92         priv->phy_dev->priv = priv;
  93         priv->phy_dev->drv = &priv->conv_phy_drv;
  94
  95         return 0;
  96 }
  97
  98 static const struct of_device_id xgmiitorgmii_of_match[] = {
  99         { .compatible = "xlnx,gmii-to-rgmii-1.0" },
 100         {},
 101 };
 102 MODULE_DEVICE_TABLE(of, xgmiitorgmii_of_match);
 103
 104 static struct mdio_driver xgmiitorgmii_driver = {
 105         .probe  = xgmiitorgmii_probe,
 106         .mdiodrv.driver = {
 107                 .name = "xgmiitorgmii",
 108                 .of_match_table = xgmiitorgmii_of_match,
 109         },
 110 };
 111
 112 mdio_module_driver(xgmiitorgmii_driver);
 113
 114 MODULE_DESCRIPTION("Xilinx GMII2RGMII converter driver");
 115 MODULE_LICENSE("GPL");