fec_mpc52xx_phy.c

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/*
 * Driver for the MPC5200 Fast Ethernet Controller - MDIO bus driver
 *
 * Copyright (C) 2007  Domen Puncer, Telargo, Inc.
 * Copyright (C) 2008  Wolfram Sang, Pengutronix
 *
 * This file is licensed under the terms of the GNU General Public License
 * version 2. This program is licensed "as is" without any warranty of any
 * kind, whether express or implied.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/phy.h>
#include <linux/of_platform.h>
#include <linux/slab.h>
#include <linux/of_mdio.h>
#include <asm/io.h>
#include <asm/mpc52xx.h>
#include "fec_mpc52xx.h"

struct mpc52xx_fec_mdio_priv {
    struct mpc52xx_fec __iomem *regs;
    int mdio_irqs[PHY_MAX_ADDR];
};

static int mpc52xx_fec_mdio_transfer(struct mii_bus *bus, int phy_id,
        int reg, u32 value)
{
    struct mpc52xx_fec_mdio_priv *priv = bus->priv;
    struct mpc52xx_fec __iomem *fec = priv->regs;
    int tries = 3;

    value |= (phy_id << FEC_MII_DATA_PA_SHIFT) & FEC_MII_DATA_PA_MSK;
    value |= (reg << FEC_MII_DATA_RA_SHIFT) & FEC_MII_DATA_RA_MSK;

    out_be32(&fec->ievent, FEC_IEVENT_MII);
    out_be32(&fec->mii_data, value);

    /* wait for it to finish, this takes about 23 us on lite5200b */
    while (!(in_be32(&fec->ievent) & FEC_IEVENT_MII) && --tries)
        msleep(1);

    if (!tries)
        return -ETIMEDOUT;

    return value & FEC_MII_DATA_OP_RD ?
        in_be32(&fec->mii_data) & FEC_MII_DATA_DATAMSK : 0;
}

static int mpc52xx_fec_mdio_read(struct mii_bus *bus, int phy_id, int reg)
{
    return mpc52xx_fec_mdio_transfer(bus, phy_id, reg, FEC_MII_READ_FRAME);
}

static int mpc52xx_fec_mdio_write(struct mii_bus *bus, int phy_id, int reg,
        u16 data)
{
    return mpc52xx_fec_mdio_transfer(bus, phy_id, reg,
        data | FEC_MII_WRITE_FRAME);
}

static int mpc52xx_fec_mdio_probe(struct platform_device *of)
{
    struct device *dev = &of->dev;
    struct device_node *np = of->dev.of_node;
    struct mii_bus *bus;
    struct mpc52xx_fec_mdio_priv *priv;
    struct resource res;
    int err;

    bus = mdiobus_alloc();
    if (bus == NULL)
        return -ENOMEM;
    priv = kzalloc(sizeof(*priv), GFP_KERNEL);
    if (priv == NULL) {
        err = -ENOMEM;
        goto out_free;
    }

    bus->name = "mpc52xx MII bus";
    bus->read = mpc52xx_fec_mdio_read;
    bus->write = mpc52xx_fec_mdio_write;

    /* setup irqs */
    bus->irq = priv->mdio_irqs;

    /* setup registers */
    err = of_address_to_resource(np, 0, &res);
    if (err)
        goto out_free;
    priv->regs = ioremap(res.start, resource_size(&res));
    if (priv->regs == NULL) {
        err = -ENOMEM;
        goto out_free;
    }

    snprintf(bus->id, MII_BUS_ID_SIZE, "%x", res.start);
    bus->priv = priv;

    bus->parent = dev;
    dev_set_drvdata(dev, bus);

    /* set MII speed */
    out_be32(&priv->regs->mii_speed,
        ((mpc5xxx_get_bus_frequency(of->dev.of_node) >> 20) / 5) << 1);

    err = of_mdiobus_register(bus, np);
    if (err)
        goto out_unmap;

    return 0;

 out_unmap:
    iounmap(priv->regs);
 out_free:
    kfree(priv);
    mdiobus_free(bus);

    return err;
}

static int mpc52xx_fec_mdio_remove(struct platform_device *of)
{
    struct device *dev = &of->dev;
    struct mii_bus *bus = dev_get_drvdata(dev);
    struct mpc52xx_fec_mdio_priv *priv = bus->priv;

    mdiobus_unregister(bus);
    dev_set_drvdata(dev, NULL);
    iounmap(priv->regs);
    kfree(priv);
    mdiobus_free(bus);

    return 0;
}

static struct of_device_id mpc52xx_fec_mdio_match[] = {
    { .compatible = "fsl,mpc5200b-mdio", },
    { .compatible = "fsl,mpc5200-mdio", },
    { .compatible = "mpc5200b-fec-phy", },
    {}
};
MODULE_DEVICE_TABLE(of, mpc52xx_fec_mdio_match);

struct platform_driver mpc52xx_fec_mdio_driver = {
    .driver = {
        .name = "mpc5200b-fec-phy",
        .owner = THIS_MODULE,
        .of_match_table = mpc52xx_fec_mdio_match,
    },
    .probe = mpc52xx_fec_mdio_probe,
    .remove = mpc52xx_fec_mdio_remove,
};

/* let fec driver call it, since this has to be registered before it */
EXPORT_SYMBOL_GPL(mpc52xx_fec_mdio_driver);

MODULE_LICENSE("Dual BSD/GPL");