text: /*
   * SAMSUNG EXYNOS USB HOST OHCI Controller
   *
   * Copyright (C) 2011 Samsung Electronics Co.Ltd
   * Author: Jingoo Han <jg1.han@samsung.com>
   *
   * This program is free software; you can redistribute  it and/or modify it
   * under  the terms of  the GNU General  Public License as published by the
   * Free Software Foundation;  either version 2 of the  License, or (at your
   * option) any later version.
   *
   */
  
  #include <linux/clk.h>
  #include <linux/dma-mapping.h>
  #include <linux/io.h>
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/of.h>
  #include <linux/platform_device.h>
  #include <linux/phy/phy.h>
  #include <linux/usb/phy.h>
  #include <linux/usb/samsung_usb_phy.h>
  #include <linux/usb.h>
  #include <linux/usb/hcd.h>
  #include <linux/usb/otg.h>
  
  #include "ohci.h"
  
  #define DRIVER_DESC "OHCI EXYNOS driver"
  
  static const char hcd_name[] = "ohci-exynos";
  static struct hc_driver __read_mostly exynos_ohci_hc_driver;
  
  #define to_exynos_ohci(hcd) (struct exynos_ohci_hcd *)(hcd_to_ohci(hcd)->priv)
  
  #define PHY_NUMBER 3
  
  struct exynos_ohci_hcd {
  	struct clk *clk;
  	struct usb_phy *phy;
  	struct usb_otg *otg;
  	struct phy *phy_g[PHY_NUMBER];
  };
  
  static int exynos_ohci_get_phy(struct device *dev,
  				struct exynos_ohci_hcd *exynos_ohci)
  {
  	struct device_node *child;
  	struct phy *phy;
  	int phy_number;
  	int ret = 0;
  
  	exynos_ohci->phy = devm_usb_get_phy(dev, USB_PHY_TYPE_USB2);
  	if (IS_ERR(exynos_ohci->phy)) {
  		ret = PTR_ERR(exynos_ohci->phy);
  		if (ret != -ENXIO && ret != -ENODEV) {
  			dev_err(dev, "no usb2 phy configured\n");
  			return ret;
  		}
  		dev_dbg(dev, "Failed to get usb2 phy\n");
  	} else {
  		exynos_ohci->otg = exynos_ohci->phy->otg;
  	}
  
  	/*
  	 * Getting generic phy:
  	 * We are keeping both types of phys as a part of transiting OHCI
  	 * to generic phy framework, so as to maintain backward compatibilty
  	 * with old DTB.
  	 * If there are existing devices using DTB files built from them,
  	 * to remove the support for old bindings in this driver,
  	 * we need to make sure that such devices have their DTBs
  	 * updated to ones built from new DTS.
  	 */
  	for_each_available_child_of_node(dev->of_node, child) {
  		ret = of_property_read_u32(child, "reg", &phy_number);
  		if (ret) {
  			dev_err(dev, "Failed to parse device tree\n");
  			of_node_put(child);
  			return ret;
  		}
  
  		if (phy_number >= PHY_NUMBER) {
  			dev_err(dev, "Invalid number of PHYs\n");
  			of_node_put(child);
  			return -EINVAL;
  		}
  
  		phy = devm_of_phy_get(dev, child, 0);
  		of_node_put(child);
  		if (IS_ERR(phy)) {
  			ret = PTR_ERR(phy);
  			if (ret != -ENOSYS && ret != -ENODEV) {
  				dev_err(dev, "no usb2 phy configured\n");
  				return ret;
  			}
  			dev_dbg(dev, "Failed to get usb2 phy\n");
  		}
  		exynos_ohci->phy_g[phy_number] = phy;
  	}
  
  	return ret;
  }
  
  static int exynos_ohci_phy_enable(struct device *dev)
  {
  	struct usb_hcd *hcd = dev_get_drvdata(dev);
  	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
  	int i;
  	int ret = 0;
  
  	if (!IS_ERR(exynos_ohci->phy))
  		return usb_phy_init(exynos_ohci->phy);
  
  	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
  		if (!IS_ERR(exynos_ohci->phy_g[i]))
  			ret = phy_power_on(exynos_ohci->phy_g[i]);
  	if (ret)
  		for (i--; i >= 0; i--)
  			if (!IS_ERR(exynos_ohci->phy_g[i]))
  				phy_power_off(exynos_ohci->phy_g[i]);
  
  	return ret;
  }
  
  static void exynos_ohci_phy_disable(struct device *dev)
  {
  	struct usb_hcd *hcd = dev_get_drvdata(dev);
  	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
  	int i;
  
  	if (!IS_ERR(exynos_ohci->phy)) {
  		usb_phy_shutdown(exynos_ohci->phy);
  		return;
  	}
  
  	for (i = 0; i < PHY_NUMBER; i++)
  		if (!IS_ERR(exynos_ohci->phy_g[i]))
  			phy_power_off(exynos_ohci->phy_g[i]);
  }
  
  static int exynos_ohci_probe(struct platform_device *pdev)
  {
  	struct exynos_ohci_hcd *exynos_ohci;
  	struct usb_hcd *hcd;
  	struct resource *res;
  	int irq;
  	int err;
  
  	/*
  	 * Right now device-tree probed devices don't get dma_mask set.
  	 * Since shared usb code relies on it, set it here for now.
  	 * Once we move to full device tree support this will vanish off.
  	 */
  	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
  	if (err)
  		return err;
  
  	hcd = usb_create_hcd(&exynos_ohci_hc_driver,
  				&pdev->dev, dev_name(&pdev->dev));
  	if (!hcd) {
  		dev_err(&pdev->dev, "Unable to create HCD\n");
  		return -ENOMEM;
  	}
  
  	exynos_ohci = to_exynos_ohci(hcd);
  
  	if (of_device_is_compatible(pdev->dev.of_node,
  					"samsung,exynos5440-ohci"))
  		goto skip_phy;
  
  	err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci);
  	if (err)
  		goto fail_clk;
  
  skip_phy:
  	exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost");
  
  	if (IS_ERR(exynos_ohci->clk)) {
  		dev_err(&pdev->dev, "Failed to get usbhost clock\n");
  		err = PTR_ERR(exynos_ohci->clk);
  		goto fail_clk;
  	}
  
  	err = clk_prepare_enable(exynos_ohci->clk);
  	if (err)
  		goto fail_clk;
  
  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  	if (!res) {
  		dev_err(&pdev->dev, "Failed to get I/O memory\n");
  		err = -ENXIO;
  		goto fail_io;
  	}
  
  	hcd->rsrc_start = res->start;
  	hcd->rsrc_len = resource_size(res);
  	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
  	if (IS_ERR(hcd->regs)) {
  		err = PTR_ERR(hcd->regs);
  		goto fail_io;
  	}
  
  	irq = platform_get_irq(pdev, 0);
  	if (!irq) {
  		dev_err(&pdev->dev, "Failed to get IRQ\n");
  		err = -ENODEV;
  		goto fail_io;
  	}
  
  	if (exynos_ohci->otg)
  		exynos_ohci->otg->set_host(exynos_ohci->otg, &hcd->self);
  
  	platform_set_drvdata(pdev, hcd);
  
  	err = exynos_ohci_phy_enable(&pdev->dev);
  	if (err) {
  		dev_err(&pdev->dev, "Failed to enable USB phy\n");
  		goto fail_io;
  	}
  
  	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
  	if (err) {
  		dev_err(&pdev->dev, "Failed to add USB HCD\n");
  		goto fail_add_hcd;
  	}
  	device_wakeup_enable(hcd->self.controller);
  	return 0;
  
  fail_add_hcd:
  	exynos_ohci_phy_disable(&pdev->dev);
  fail_io:
  	clk_disable_unprepare(exynos_ohci->clk);
  fail_clk:
  	usb_put_hcd(hcd);
  	return err;
  }
  
  static int exynos_ohci_remove(struct platform_device *pdev)
  {
  	struct usb_hcd *hcd = platform_get_drvdata(pdev);
  	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
  
  	usb_remove_hcd(hcd);
  
  	if (exynos_ohci->otg)
  		exynos_ohci->otg->set_host(exynos_ohci->otg, &hcd->self);
  
  	exynos_ohci_phy_disable(&pdev->dev);
  
  	clk_disable_unprepare(exynos_ohci->clk);
  
  	usb_put_hcd(hcd);
  
  	return 0;
  }
  
  static void exynos_ohci_shutdown(struct platform_device *pdev)
  {
  	struct usb_hcd *hcd = platform_get_drvdata(pdev);
  
  	if (hcd->driver->shutdown)
  		hcd->driver->shutdown(hcd);
  }
  
  #ifdef CONFIG_PM
  static int exynos_ohci_suspend(struct device *dev)
  {
  	struct usb_hcd *hcd = dev_get_drvdata(dev);
  	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
  	bool do_wakeup = device_may_wakeup(dev);
  	int rc = ohci_suspend(hcd, do_wakeup);
  
  	if (rc)
  		return rc;
  
  	if (exynos_ohci->otg)
  		exynos_ohci->otg->set_host(exynos_ohci->otg, &hcd->self);
  
  	exynos_ohci_phy_disable(dev);
  
  	clk_disable_unprepare(exynos_ohci->clk);
  
  	return 0;
  }
  
  static int exynos_ohci_resume(struct device *dev)
  {
  	struct usb_hcd *hcd			= dev_get_drvdata(dev);
  	struct exynos_ohci_hcd *exynos_ohci	= to_exynos_ohci(hcd);
  	int ret;
  
  	clk_prepare_enable(exynos_ohci->clk);
  
  	if (exynos_ohci->otg)
  		exynos_ohci->otg->set_host(exynos_ohci->otg, &hcd->self);
  
  	ret = exynos_ohci_phy_enable(dev);
  	if (ret) {
  		dev_err(dev, "Failed to enable USB phy\n");
  		clk_disable_unprepare(exynos_ohci->clk);
  		return ret;
  	}
  
  	ohci_resume(hcd, false);
  
  	return 0;
  }
  #else
  #define exynos_ohci_suspend	NULL
  #define exynos_ohci_resume	NULL
  #endif
  
  static const struct ohci_driver_overrides exynos_overrides __initconst = {
  	.extra_priv_size =	sizeof(struct exynos_ohci_hcd),
  };
  
  static const struct dev_pm_ops exynos_ohci_pm_ops = {
  	.suspend	= exynos_ohci_suspend,
  	.resume		= exynos_ohci_resume,
  };
  
  #ifdef CONFIG_OF
  static const struct of_device_id exynos_ohci_match[] = {
  	{ .compatible = "samsung,exynos4210-ohci" },
  	{ .compatible = "samsung,exynos5440-ohci" },
  	{},
  };
  MODULE_DEVICE_TABLE(of, exynos_ohci_match);
  #endif
  
  static struct platform_driver exynos_ohci_driver = {
  	.probe		= exynos_ohci_probe,
  	.remove		= exynos_ohci_remove,
  	.shutdown	= exynos_ohci_shutdown,
  	.driver = {
  		.name	= "exynos-ohci",
  		.owner	= THIS_MODULE,
  		.pm	= &exynos_ohci_pm_ops,
  		.of_match_table	= of_match_ptr(exynos_ohci_match),
  	}
  };
  static int __init ohci_exynos_init(void)
  {
  	if (usb_disabled())
  		return -ENODEV;
  
  	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
  	ohci_init_driver(&exynos_ohci_hc_driver, &exynos_overrides);
  	return platform_driver_register(&exynos_ohci_driver);
  }
  module_init(ohci_exynos_init);
  
  static void __exit ohci_exynos_cleanup(void)
  {
  	platform_driver_unregister(&exynos_ohci_driver);
  }
  module_exit(ohci_exynos_cleanup);
  
  MODULE_ALIAS("platform:exynos-ohci");
  MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
  MODULE_LICENSE("GPL v2");
  