/* ehci-msm.c - HSUSB Host Controller Driver Implementation
   *
   * Copyright (c) 2008-2011, Code Aurora Forum. All rights reserved.
   *
   * Partly derived from ehci-fsl.c and ehci-hcd.c
   * Copyright (c) 2000-2004 by David Brownell
   * Copyright (c) 2005 MontaVista Software
   *
   * All source code in this file is licensed under the following license except
   * where indicated.
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 as published
   * by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   *
   * See the GNU General Public License for more details.
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, you can find it at http://www.fsf.org
   */
  
  #include <linux/clk.h>
  #include <linux/err.h>
  #include <linux/io.h>
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/platform_device.h>
  #include <linux/pm_runtime.h>
  #include <linux/usb/otg.h>
  #include <linux/usb/msm_hsusb_hw.h>
  #include <linux/usb.h>
  #include <linux/usb/hcd.h>
  
  #include "ehci.h"
  
  #define MSM_USB_BASE (hcd->regs)
  
  #define DRIVER_DESC "Qualcomm On-Chip EHCI Host Controller"
  
  static const char hcd_name[] = "ehci-msm";
  static struct hc_driver __read_mostly msm_hc_driver;
  
  static int ehci_msm_reset(struct usb_hcd *hcd)
  {
  	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
  	int retval;
  
  	ehci->caps = USB_CAPLENGTH;
  	hcd->has_tt = 1;
  
  	retval = ehci_setup(hcd);
  	if (retval)
  		return retval;
  
  	/* bursts of unspecified length. */
  	writel(0, USB_AHBBURST);
  	/* Use the AHB transactor */
  	writel(0, USB_AHBMODE);
  	/* Disable streaming mode and select host mode */
  	writel(0x13, USB_USBMODE);
  
  	return 0;
  }
  
  static int ehci_msm_probe(struct platform_device *pdev)
  {
  	struct usb_hcd *hcd;
  	struct resource *res;
  	struct usb_phy *phy;
  	int ret;
  
  	dev_dbg(&pdev->dev, "ehci_msm proble
  ");
  
  	hcd = usb_create_hcd(&msm_hc_driver, &pdev->dev, dev_name(&pdev->dev));
  	if (!hcd) {
  		dev_err(&pdev->dev, "Unable to create HCD
  ");
  		return  -ENOMEM;
  	}
  
  	hcd->irq = platform_get_irq(pdev, 0);
  	if (hcd->irq < 0) {
  		dev_err(&pdev->dev, "Unable to get IRQ resource
  ");
  		ret = hcd->irq;
  		goto put_hcd;
  	}
  
  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  	if (!res) {
  		dev_err(&pdev->dev, "Unable to get memory resource
  ");
  		ret = -ENODEV;
  		goto put_hcd;
  	}
  
  	hcd->rsrc_start = res->start;
  	hcd->rsrc_len = resource_size(res);
  	hcd->regs = devm_ioremap(&pdev->dev, hcd->rsrc_start, hcd->rsrc_len);
  	if (!hcd->regs) {
  		dev_err(&pdev->dev, "ioremap failed
  ");
  		ret = -ENOMEM;
  		goto put_hcd;
  	}
  
  	/*
  	 * OTG driver takes care of PHY initialization, clock management,
  	 * powering up VBUS, mapping of registers address space and power
  	 * management.
  	 */
  	if (pdev->dev.of_node)
  		phy = devm_usb_get_phy_by_phandle(&pdev->dev, "usb-phy", 0);
  	else
  		phy = devm_usb_get_phy(&pdev->dev, USB_PHY_TYPE_USB2);
  
  	if (IS_ERR(phy)) {
  		dev_err(&pdev->dev, "unable to find transceiver
  ");
  		ret = -EPROBE_DEFER;
  		goto put_hcd;
  	}
  
  	ret = otg_set_host(phy->otg, &hcd->self);
  	if (ret < 0) {
  		dev_err(&pdev->dev, "unable to register with transceiver
  ");
  		goto put_hcd;
  	}
  
  	hcd->usb_phy = phy;
  	device_init_wakeup(&pdev->dev, 1);
  	/*
  	 * OTG device parent of HCD takes care of putting
  	 * hardware into low power mode.
  	 */
  	pm_runtime_no_callbacks(&pdev->dev);
  	pm_runtime_enable(&pdev->dev);
  
  	/* FIXME: need to call usb_add_hcd() here? */
  
  	return 0;
  
  put_hcd:
  	usb_put_hcd(hcd);
  
  	return ret;
  }
  
  static int ehci_msm_remove(struct platform_device *pdev)
  {
  	struct usb_hcd *hcd = platform_get_drvdata(pdev);
  
  	device_init_wakeup(&pdev->dev, 0);
  	pm_runtime_disable(&pdev->dev);
  	pm_runtime_set_suspended(&pdev->dev);
  
  	otg_set_host(hcd->usb_phy->otg, NULL);
  
  	/* FIXME: need to call usb_remove_hcd() here? */
  
  	usb_put_hcd(hcd);
  
  	return 0;
  }
  
  #ifdef CONFIG_PM
  static int ehci_msm_pm_suspend(struct device *dev)
  {
  	struct usb_hcd *hcd = dev_get_drvdata(dev);
  	bool do_wakeup = device_may_wakeup(dev);
  
  	dev_dbg(dev, "ehci-msm PM suspend
  ");
  
  	return ehci_suspend(hcd, do_wakeup);
  }
  
  static int ehci_msm_pm_resume(struct device *dev)
  {
  	struct usb_hcd *hcd = dev_get_drvdata(dev);
  
  	dev_dbg(dev, "ehci-msm PM resume
  ");
  	ehci_resume(hcd, false);
  
  	return 0;
  }
  #else
  #define ehci_msm_pm_suspend	NULL
  #define ehci_msm_pm_resume	NULL
  #endif
  
  static const struct dev_pm_ops ehci_msm_dev_pm_ops = {
  	.suspend         = ehci_msm_pm_suspend,
  	.resume          = ehci_msm_pm_resume,
  };
  
  static struct of_device_id msm_ehci_dt_match[] = {
  	{ .compatible = "qcom,ehci-host", },
  	{}
  };
  MODULE_DEVICE_TABLE(of, msm_ehci_dt_match);
  
  static struct platform_driver ehci_msm_driver = {
  	.probe	= ehci_msm_probe,
  	.remove	= ehci_msm_remove,
  	.driver = {
  		   .name = "msm_hsusb_host",
  		   .pm = &ehci_msm_dev_pm_ops,
  		   .of_match_table = msm_ehci_dt_match,
  	},
  };
  
  static const struct ehci_driver_overrides msm_overrides __initdata = {
  	.reset = ehci_msm_reset,
  };
  
  static int __init ehci_msm_init(void)
  {
  	if (usb_disabled())
  		return -ENODEV;
  
  	pr_info("%s: " DRIVER_DESC "
  ", hcd_name);
  	ehci_init_driver(&msm_hc_driver, &msm_overrides);
  	return platform_driver_register(&ehci_msm_driver);
  }
  module_init(ehci_msm_init);
  
  static void __exit ehci_msm_cleanup(void)
  {
  	platform_driver_unregister(&ehci_msm_driver);
  }
  module_exit(ehci_msm_cleanup);
  
  MODULE_DESCRIPTION(DRIVER_DESC);
  MODULE_ALIAS("platform:msm-ehci");
  MODULE_LICENSE("GPL");