/*
 * Copyright (c) 2008 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
 * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
 *
 * 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.
 *
 * 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, write to the Free Software Foundation,
 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/usb/otg.h>
#include <linux/usb/ulpi.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>

#include <linux/platform_data/usb-ehci-mxc.h>

#include <asm/mach-types.h>

#include "ehci.h"

#define DRIVER_DESC "Freescale On-Chip EHCI Host driver"

static const char hcd_name[] = "ehci-mxc";

#define ULPI_VIEWPORT_OFFSET    0x170

struct ehci_mxc_priv {
        struct clk *usbclk, *ahbclk, *phyclk;
};

static struct hc_driver __read_mostly ehci_mxc_hc_driver;

static const struct ehci_driver_overrides ehci_mxc_overrides __initdata = {
        .extra_priv_size =      sizeof(struct ehci_mxc_priv),
};

static int ehci_mxc_drv_probe(struct platform_device *pdev)
{
        struct mxc_usbh_platform_data *pdata = pdev->dev.platform_data;
        struct usb_hcd *hcd;
        struct resource *res;
        int irq, ret;
        struct ehci_mxc_priv *priv;
        struct device *dev = &pdev->dev;
        struct ehci_hcd *ehci;

        dev_info(&pdev->dev, "initializing i.MX USB Controller\n");

        if (!pdata) {
                dev_err(dev, "No platform data given, bailing out.\n");
                return -EINVAL;
        }

        irq = platform_get_irq(pdev, 0);

        hcd = usb_create_hcd(&ehci_mxc_hc_driver, dev, dev_name(dev));
        if (!hcd)
                return -ENOMEM;

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!res) {
                dev_err(dev, "Found HC with no register addr. Check setup!\n");
                ret = -ENODEV;
                goto err_alloc;
        }

        hcd->rsrc_start = res->start;
        hcd->rsrc_len = resource_size(res);

        hcd->regs = devm_ioremap_resource(&pdev->dev, res);
        if (IS_ERR(hcd->regs)) {
                ret = PTR_ERR(hcd->regs);
                goto err_alloc;
        }

        hcd->has_tt = 1;
        ehci = hcd_to_ehci(hcd);
        priv = (struct ehci_mxc_priv *) ehci->priv;

        /* enable clocks */
        priv->usbclk = devm_clk_get(&pdev->dev, "ipg");
        if (IS_ERR(priv->usbclk)) {
                ret = PTR_ERR(priv->usbclk);
                goto err_alloc;
        }
        clk_prepare_enable(priv->usbclk);

        priv->ahbclk = devm_clk_get(&pdev->dev, "ahb");
        if (IS_ERR(priv->ahbclk)) {
                ret = PTR_ERR(priv->ahbclk);
                goto err_clk_ahb;
        }
        clk_prepare_enable(priv->ahbclk);

        /* "dr" device has its own clock on i.MX51 */
        priv->phyclk = devm_clk_get(&pdev->dev, "phy");
        if (IS_ERR(priv->phyclk))
                priv->phyclk = NULL;
        if (priv->phyclk)
                clk_prepare_enable(priv->phyclk);


        /* call platform specific init function */
        if (pdata->init) {
                ret = pdata->init(pdev);
                if (ret) {
                        dev_err(dev, "platform init failed\n");
                        goto err_init;
                }
                /* platforms need some time to settle changed IO settings */
                mdelay(10);
        }

        /* EHCI registers start at offset 0x100 */
        ehci->caps = hcd->regs + 0x100;
        ehci->regs = hcd->regs + 0x100 +
                HC_LENGTH(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase));

        /* set up the PORTSCx register */
        ehci_writel(ehci, pdata->portsc, &ehci->regs->port_status[0]);

        /* is this really needed? */
        msleep(10);

        /* Initialize the transceiver */
        if (pdata->otg) {
                pdata->otg->io_priv = hcd->regs + ULPI_VIEWPORT_OFFSET;
                ret = usb_phy_init(pdata->otg);
                if (ret) {
                        dev_err(dev, "unable to init transceiver, probably missing\n");
                        ret = -ENODEV;
                        goto err_add;
                }
                ret = otg_set_vbus(pdata->otg->otg, 1);
                if (ret) {
                        dev_err(dev, "unable to enable vbus on transceiver\n");
                        goto err_add;
                }
        }

        platform_set_drvdata(pdev, hcd);

        ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
        if (ret)
                goto err_add;

        return 0;

err_add:
        if (pdata && pdata->exit)
                pdata->exit(pdev);
err_init:
        if (priv->phyclk)
                clk_disable_unprepare(priv->phyclk);

        clk_disable_unprepare(priv->ahbclk);
err_clk_ahb:
        clk_disable_unprepare(priv->usbclk);
err_alloc:
        usb_put_hcd(hcd);
        return ret;
}

static int __exit ehci_mxc_drv_remove(struct platform_device *pdev)
{
        struct mxc_usbh_platform_data *pdata = pdev->dev.platform_data;
        struct usb_hcd *hcd = platform_get_drvdata(pdev);
        struct ehci_hcd *ehci = hcd_to_ehci(hcd);
        struct ehci_mxc_priv *priv = (struct ehci_mxc_priv *) ehci->priv;

        usb_remove_hcd(hcd);

        if (pdata && pdata->exit)
                pdata->exit(pdev);

        if (pdata->otg)
                usb_phy_shutdown(pdata->otg);

        clk_disable_unprepare(priv->usbclk);
        clk_disable_unprepare(priv->ahbclk);

        if (priv->phyclk)
                clk_disable_unprepare(priv->phyclk);

        usb_put_hcd(hcd);
        platform_set_drvdata(pdev, NULL);
        return 0;
}

static void ehci_mxc_drv_shutdown(struct platform_device *pdev)
{
        struct usb_hcd *hcd = platform_get_drvdata(pdev);

        if (hcd->driver->shutdown)
                hcd->driver->shutdown(hcd);
}

MODULE_ALIAS("platform:mxc-ehci");

static struct platform_driver ehci_mxc_driver = {
        .probe = ehci_mxc_drv_probe,
        .remove = ehci_mxc_drv_remove,
        .shutdown = ehci_mxc_drv_shutdown,
        .driver = {
                   .name = "mxc-ehci",
        },
};

static int __init ehci_mxc_init(void)
{
        if (usb_disabled())
                return -ENODEV;

        pr_info("%s: " DRIVER_DESC "\n", hcd_name);

        ehci_init_driver(&ehci_mxc_hc_driver, &ehci_mxc_overrides);
        return platform_driver_register(&ehci_mxc_driver);
}
module_init(ehci_mxc_init);

static void __exit ehci_mxc_cleanup(void)
{
        platform_driver_unregister(&ehci_mxc_driver);
}
module_exit(ehci_mxc_cleanup);

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Sascha Hauer");
MODULE_LICENSE("GPL");