/* 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\n");

        hcd = usb_create_hcd(&msm_hc_driver, &pdev->dev, dev_name(&pdev->dev));
        if (!hcd) {
                dev_err(&pdev->dev, "Unable to create HCD\n");
                return  -ENOMEM;
        }

        hcd->irq = platform_get_irq(pdev, 0);
        if (hcd->irq < 0) {
                dev_err(&pdev->dev, "Unable to get IRQ resource\n");
                ret = hcd->irq;
                goto put_hcd;
        }

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        hcd->regs = devm_ioremap_resource(&pdev->dev, res);
        if (IS_ERR(hcd->regs)) {
                ret = PTR_ERR(hcd->regs);
                goto put_hcd;
        }
        hcd->rsrc_start = res->start;
        hcd->rsrc_len = resource_size(res);

        /*
         * 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\n");
                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\n");
                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\n");

        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\n");
        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 const 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 "\n", 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");