text: // 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 = 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, "%px", 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,
  };
  
  module_platform_driver(octeon_mdiobus_driver);
  
  MODULE_DESCRIPTION("Cavium OCTEON MDIO bus driver");
  MODULE_AUTHOR("David Daney");
  MODULE_LICENSE("GPL v2");
  