drivers/net/ethernet/freescale/fec_mpc52xx_phy.c

   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_mdio.h>
  19 #include <asm/io.h>
  20 #include <asm/mpc52xx.h>
  21 #include "fec_mpc52xx.h"
  22
  23 struct mpc52xx_fec_mdio_priv {
  24         struct mpc52xx_fec __iomem *regs;
  25 };
  26
  27 static int mpc52xx_fec_mdio_transfer(struct mii_bus *bus, int phy_id,
  28                 int reg, u32 value)
  29 {
  30         struct mpc52xx_fec_mdio_priv *priv = bus->priv;
  31         struct mpc52xx_fec __iomem *fec = priv->regs;
  32         int tries = 3;
  33
  34         value |= (phy_id << FEC_MII_DATA_PA_SHIFT) & FEC_MII_DATA_PA_MSK;
  35         value |= (reg << FEC_MII_DATA_RA_SHIFT) & FEC_MII_DATA_RA_MSK;
  36
  37         out_be32(&fec->ievent, FEC_IEVENT_MII);
  38         out_be32(&fec->mii_data, value);
  39
  40         /* wait for it to finish, this takes about 23 us on lite5200b */
  41         while (!(in_be32(&fec->ievent) & FEC_IEVENT_MII) && --tries)
  42                 msleep(1);
  43
  44         if (!tries)
  45                 return -ETIMEDOUT;
  46
  47         return value & FEC_MII_DATA_OP_RD ?
  48                 in_be32(&fec->mii_data) & FEC_MII_DATA_DATAMSK : 0;
  49 }
  50
  51 static int mpc52xx_fec_mdio_read(struct mii_bus *bus, int phy_id, int reg)
  52 {
  53         return mpc52xx_fec_mdio_transfer(bus, phy_id, reg, FEC_MII_READ_FRAME);
  54 }
  55
  56 static int mpc52xx_fec_mdio_write(struct mii_bus *bus, int phy_id, int reg,
  57                 u16 data)
  58 {
  59         return mpc52xx_fec_mdio_transfer(bus, phy_id, reg,
  60                 data | FEC_MII_WRITE_FRAME);
  61 }
  62
  63 static int mpc52xx_fec_mdio_probe(struct platform_device *of)
  64 {
  65         struct device *dev = &of->dev;
  66         struct device_node *np = of->dev.of_node;
  67         struct mii_bus *bus;
  68         struct mpc52xx_fec_mdio_priv *priv;
  69         struct resource res;
  70         int err;
  71
  72         bus = mdiobus_alloc();
  73         if (bus == NULL)
  74                 return -ENOMEM;
  75         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
  76         if (priv == NULL) {
  77                 err = -ENOMEM;
  78                 goto out_free;
  79         }
  80
  81         bus->name = "mpc52xx MII bus";
  82         bus->read = mpc52xx_fec_mdio_read;
  83         bus->write = mpc52xx_fec_mdio_write;
  84
  85         /* setup registers */
  86         err = of_address_to_resource(np, 0, &res);
  87         if (err)
  88                 goto out_free;
  89         priv->regs = ioremap(res.start, resource_size(&res));
  90         if (priv->regs == NULL) {
  91                 err = -ENOMEM;
  92                 goto out_free;
  93         }
  94
  95         snprintf(bus->id, MII_BUS_ID_SIZE, "%x", res.start);
  96         bus->priv = priv;
  97
  98         bus->parent = dev;
  99         dev_set_drvdata(dev, bus);
 100
 101         /* set MII speed */
 102         out_be32(&priv->regs->mii_speed,
 103                 ((mpc5xxx_get_bus_frequency(of->dev.of_node) >> 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
 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");