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
xgmiitorgmii_configure(struct gmii2rgmii * priv,int speed)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
xgmiitorgmii_read_status(struct phy_device * phydev)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
xgmiitorgmii_set_loopback(struct phy_device * phydev,bool enable)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
xgmiitorgmii_probe(struct mdio_device * mdiodev)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");
142