1 /*
2 * Driver for the MPC5200 Fast Ethernet Controller - MDIO bus driver
3 *
4 * Copyright (C) 2007 Domen Puncer, Telargo, Inc.
5 * Copyright (C) 2008 Wolfram Sang, Pengutronix
6 *
7 * This file is licensed under the terms of the GNU General Public License
8 * version 2. This program is licensed "as is" without any warranty of any
9 * kind, whether express or implied.
10 */
11
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/netdevice.h>
15 #include <linux/phy.h>
16 #include <linux/of_platform.h>
17 #include <linux/slab.h>
18 #include <linux/of_address.h>
19 #include <linux/of_mdio.h>
20 #include <asm/io.h>
21 #include <asm/mpc52xx.h>
22 #include "fec_mpc52xx.h"
23
24 struct mpc52xx_fec_mdio_priv {
25 struct mpc52xx_fec __iomem *regs;
26 };
27
mpc52xx_fec_mdio_transfer(struct mii_bus * bus,int phy_id,int reg,u32 value)28 static int mpc52xx_fec_mdio_transfer(struct mii_bus *bus, int phy_id,
29 int reg, u32 value)
30 {
31 struct mpc52xx_fec_mdio_priv *priv = bus->priv;
32 struct mpc52xx_fec __iomem *fec = priv->regs;
33 int tries = 3;
34
35 value |= (phy_id << FEC_MII_DATA_PA_SHIFT) & FEC_MII_DATA_PA_MSK;
36 value |= (reg << FEC_MII_DATA_RA_SHIFT) & FEC_MII_DATA_RA_MSK;
37
38 out_be32(&fec->ievent, FEC_IEVENT_MII);
39 out_be32(&fec->mii_data, value);
40
41 /* wait for it to finish, this takes about 23 us on lite5200b */
42 while (!(in_be32(&fec->ievent) & FEC_IEVENT_MII) && --tries)
43 msleep(1);
44
45 if (!tries)
46 return -ETIMEDOUT;
47
48 return value & FEC_MII_DATA_OP_RD ?
49 in_be32(&fec->mii_data) & FEC_MII_DATA_DATAMSK : 0;
50 }
51
mpc52xx_fec_mdio_read(struct mii_bus * bus,int phy_id,int reg)52 static int mpc52xx_fec_mdio_read(struct mii_bus *bus, int phy_id, int reg)
53 {
54 return mpc52xx_fec_mdio_transfer(bus, phy_id, reg, FEC_MII_READ_FRAME);
55 }
56
mpc52xx_fec_mdio_write(struct mii_bus * bus,int phy_id,int reg,u16 data)57 static int mpc52xx_fec_mdio_write(struct mii_bus *bus, int phy_id, int reg,
58 u16 data)
59 {
60 return mpc52xx_fec_mdio_transfer(bus, phy_id, reg,
61 data | FEC_MII_WRITE_FRAME);
62 }
63
mpc52xx_fec_mdio_probe(struct platform_device * of)64 static int mpc52xx_fec_mdio_probe(struct platform_device *of)
65 {
66 struct device *dev = &of->dev;
67 struct device_node *np = of->dev.of_node;
68 struct mii_bus *bus;
69 struct mpc52xx_fec_mdio_priv *priv;
70 struct resource res;
71 int err;
72
73 bus = mdiobus_alloc();
74 if (bus == NULL)
75 return -ENOMEM;
76 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
77 if (priv == NULL) {
78 err = -ENOMEM;
79 goto out_free;
80 }
81
82 bus->name = "mpc52xx MII bus";
83 bus->read = mpc52xx_fec_mdio_read;
84 bus->write = mpc52xx_fec_mdio_write;
85
86 /* setup registers */
87 err = of_address_to_resource(np, 0, &res);
88 if (err)
89 goto out_free;
90 priv->regs = ioremap(res.start, resource_size(&res));
91 if (priv->regs == NULL) {
92 err = -ENOMEM;
93 goto out_free;
94 }
95
96 snprintf(bus->id, MII_BUS_ID_SIZE, "%x", res.start);
97 bus->priv = priv;
98
99 bus->parent = dev;
100 dev_set_drvdata(dev, bus);
101
102 /* set MII speed */
103 out_be32(&priv->regs->mii_speed, ((mpc5xxx_get_bus_frequency(dev) >> 20) / 5) << 1);
104
105 err = of_mdiobus_register(bus, np);
106 if (err)
107 goto out_unmap;
108
109 return 0;
110
111 out_unmap:
112 iounmap(priv->regs);
113 out_free:
114 kfree(priv);
115 mdiobus_free(bus);
116
117 return err;
118 }
119
mpc52xx_fec_mdio_remove(struct platform_device * of)120 static int mpc52xx_fec_mdio_remove(struct platform_device *of)
121 {
122 struct mii_bus *bus = platform_get_drvdata(of);
123 struct mpc52xx_fec_mdio_priv *priv = bus->priv;
124
125 mdiobus_unregister(bus);
126 iounmap(priv->regs);
127 kfree(priv);
128 mdiobus_free(bus);
129
130 return 0;
131 }
132
133 static const struct of_device_id mpc52xx_fec_mdio_match[] = {
134 { .compatible = "fsl,mpc5200b-mdio", },
135 { .compatible = "fsl,mpc5200-mdio", },
136 { .compatible = "mpc5200b-fec-phy", },
137 {}
138 };
139 MODULE_DEVICE_TABLE(of, mpc52xx_fec_mdio_match);
140
141 struct platform_driver mpc52xx_fec_mdio_driver = {
142 .driver = {
143 .name = "mpc5200b-fec-phy",
144 .owner = THIS_MODULE,
145 .of_match_table = mpc52xx_fec_mdio_match,
146 },
147 .probe = mpc52xx_fec_mdio_probe,
148 .remove = mpc52xx_fec_mdio_remove,
149 };
150
151 /* let fec driver call it, since this has to be registered before it */
152 EXPORT_SYMBOL_GPL(mpc52xx_fec_mdio_driver);
153
154 MODULE_LICENSE("Dual BSD/GPL");
155
