drivers/net/phy/mdio-octeon.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2009-2015 Cavium, Inc.
 */

#include <linux/platform_device.h>
#include <linux/of_address.h>
#include <linux/of_mdio.h>
#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/phy.h>
#include <linux/io.h>

#include "mdio-cavium.h"

static int octeon_mdiobus_probe(struct platform_device *pdev)
{
	struct cavium_mdiobus *bus;
	struct mii_bus *mii_bus;
	struct resource *res_mem;
	resource_size_t mdio_phys;
	resource_size_t regsize;
	union cvmx_smix_en smi_en;
	int err = -ENOENT;

	mii_bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*bus));
	if (!mii_bus)
		return -ENOMEM;

	res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (res_mem == NULL) {
		dev_err(&pdev->dev, "found no memory resource\n");
		return -ENXIO;
	}

	bus = mii_bus->priv;
	bus->mii_bus = mii_bus;
	mdio_phys = res_mem->start;
	regsize = resource_size(res_mem);

	if (!devm_request_mem_region(&pdev->dev, mdio_phys, regsize,
				     res_mem->name)) {
		dev_err(&pdev->dev, "request_mem_region failed\n");
		return -ENXIO;
	}

	bus->register_base =
		(u64)devm_ioremap(&pdev->dev, mdio_phys, regsize);
	if (!bus->register_base) {
		dev_err(&pdev->dev, "dev_ioremap failed\n");
		return -ENOMEM;
	}

	smi_en.u64 = 0;
	smi_en.s.en = 1;
	oct_mdio_writeq(smi_en.u64, bus->register_base + SMI_EN);

	bus->mii_bus->name = KBUILD_MODNAME;
	snprintf(bus->mii_bus->id, MII_BUS_ID_SIZE, "%llx", bus->register_base);
	bus->mii_bus->parent = &pdev->dev;

	bus->mii_bus->read = cavium_mdiobus_read;
	bus->mii_bus->write = cavium_mdiobus_write;

	platform_set_drvdata(pdev, bus);

	err = of_mdiobus_register(bus->mii_bus, pdev->dev.of_node);
	if (err)
		goto fail_register;

	dev_info(&pdev->dev, "Probed\n");

	return 0;
fail_register:
	mdiobus_free(bus->mii_bus);
	smi_en.u64 = 0;
	oct_mdio_writeq(smi_en.u64, bus->register_base + SMI_EN);
	return err;
}

static int octeon_mdiobus_remove(struct platform_device *pdev)
{
	struct cavium_mdiobus *bus;
	union cvmx_smix_en smi_en;

	bus = platform_get_drvdata(pdev);

	mdiobus_unregister(bus->mii_bus);
	mdiobus_free(bus->mii_bus);
	smi_en.u64 = 0;
	oct_mdio_writeq(smi_en.u64, bus->register_base + SMI_EN);
	return 0;
}

static const struct of_device_id octeon_mdiobus_match[] = {
	{
		.compatible = "cavium,octeon-3860-mdio",
	},
	{},
};
MODULE_DEVICE_TABLE(of, octeon_mdiobus_match);

static struct platform_driver octeon_mdiobus_driver = {
	.driver = {
		.name		= KBUILD_MODNAME,
		.of_match_table = octeon_mdiobus_match,
	},
	.probe		= octeon_mdiobus_probe,
	.remove		= octeon_mdiobus_remove,
};

void octeon_mdiobus_force_mod_depencency(void)
{
	/* Let ethernet drivers force us to be loaded.  */
}
EXPORT_SYMBOL(octeon_mdiobus_force_mod_depencency);

module_platform_driver(octeon_mdiobus_driver);

MODULE_DESCRIPTION("Cavium OCTEON MDIO bus driver");
MODULE_AUTHOR("David Daney");
MODULE_LICENSE("GPL v2");