/*
 * xhci-plat.c - xHCI host controller driver platform Bus Glue.
 *
 * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com
 * Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 *
 * A lot of code borrowed from the Linux xHCI driver.
 *
 * 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.
 */

#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/usb/phy.h>
#include <linux/slab.h>
#include <linux/usb/xhci_pdriver.h>

#include "xhci.h"

static struct hc_driver __read_mostly xhci_plat_hc_driver;

static void xhci_plat_quirks(struct device *dev, struct xhci_hcd *xhci)
{
        /*
         * As of now platform drivers don't provide MSI support so we ensure
         * here that the generic code does not try to make a pci_dev from our
         * dev struct in order to setup MSI
         */
        xhci->quirks |= XHCI_PLAT;
}

/* called during probe() after chip reset completes */
static int xhci_plat_setup(struct usb_hcd *hcd)
{
        return xhci_gen_setup(hcd, xhci_plat_quirks);
}

static int xhci_plat_start(struct usb_hcd *hcd)
{
        return xhci_run(hcd);
}

static int xhci_plat_probe(struct platform_device *pdev)
{
        struct device_node      *node = pdev->dev.of_node;
        struct usb_xhci_pdata   *pdata = dev_get_platdata(&pdev->dev);
        const struct hc_driver  *driver;
        struct xhci_hcd         *xhci;
        struct resource         *res;
        struct usb_hcd          *hcd;
        struct clk              *clk;
        int                     ret;
        int                     irq;

        if (usb_disabled())
                return -ENODEV;

        driver = &xhci_plat_hc_driver;

        irq = platform_get_irq(pdev, 0);
        if (irq < 0)
                return -ENODEV;


        /* Initialize dma_mask and coherent_dma_mask to 32-bits */
        ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
        if (ret)
                return ret;
        if (!pdev->dev.dma_mask)
                pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
        else
                dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));

        hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
        if (!hcd)
                return -ENOMEM;

        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);

        /*
         * Not all platforms have a clk so it is not an error if the
         * clock does not exists.
         */
        clk = devm_clk_get(&pdev->dev, NULL);
        if (!IS_ERR(clk)) {
                ret = clk_prepare_enable(clk);
                if (ret)
                        goto put_hcd;
        }

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


        /* USB 2.0 roothub is stored in the platform_device now. */
        hcd = dev_get_drvdata(&pdev->dev);
        xhci = hcd_to_xhci(hcd);
        xhci->clk = clk;
        xhci->shared_hcd = usb_create_shared_hcd(driver, &pdev->dev,
                        dev_name(&pdev->dev), hcd);
        if (!xhci->shared_hcd) {
                ret = -ENOMEM;
                goto dealloc_usb2_hcd;
        }

        if ((node && of_property_read_bool(node, "usb3-lpm-capable")) ||
                        (pdata && pdata->usb3_lpm_capable))
                xhci->quirks |= XHCI_LPM_SUPPORT;
        /*
         * Set the xHCI pointer before xhci_plat_setup() (aka hcd_driver.reset)
         * is called by usb_add_hcd().
         */
        *((struct xhci_hcd **) xhci->shared_hcd->hcd_priv) = xhci;

        if (HCC_MAX_PSA(xhci->hcc_params) >= 4)
                xhci->shared_hcd->can_do_streams = 1;

        hcd->usb_phy = devm_usb_get_phy_by_phandle(&pdev->dev, "usb-phy", 0);
        if (IS_ERR(hcd->usb_phy)) {
                ret = PTR_ERR(hcd->usb_phy);
                if (ret == -EPROBE_DEFER)
                        goto put_usb3_hcd;
                hcd->usb_phy = NULL;
        } else {
                ret = usb_phy_init(hcd->usb_phy);
                if (ret)
                        goto put_usb3_hcd;
        }

        ret = usb_add_hcd(xhci->shared_hcd, irq, IRQF_SHARED);
        if (ret)
                goto disable_usb_phy;

        return 0;

disable_usb_phy:
        usb_phy_shutdown(hcd->usb_phy);

put_usb3_hcd:
        usb_put_hcd(xhci->shared_hcd);

dealloc_usb2_hcd:
        usb_remove_hcd(hcd);

disable_clk:
        if (!IS_ERR(clk))
                clk_disable_unprepare(clk);

put_hcd:
        usb_put_hcd(hcd);

        return ret;
}

static int xhci_plat_remove(struct platform_device *dev)
{
        struct usb_hcd  *hcd = platform_get_drvdata(dev);
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
        struct clk *clk = xhci->clk;

        usb_remove_hcd(xhci->shared_hcd);
        usb_phy_shutdown(hcd->usb_phy);
        usb_put_hcd(xhci->shared_hcd);

        usb_remove_hcd(hcd);
        if (!IS_ERR(clk))
                clk_disable_unprepare(clk);
        usb_put_hcd(hcd);
        kfree(xhci);

        return 0;
}

#ifdef CONFIG_PM_SLEEP
static int xhci_plat_suspend(struct device *dev)
{
        struct usb_hcd  *hcd = dev_get_drvdata(dev);
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);

        /*
         * xhci_suspend() needs `do_wakeup` to know whether host is allowed
         * to do wakeup during suspend. Since xhci_plat_suspend is currently
         * only designed for system suspend, device_may_wakeup() is enough
         * to dertermine whether host is allowed to do wakeup. Need to
         * reconsider this when xhci_plat_suspend enlarges its scope, e.g.,
         * also applies to runtime suspend.
         */
        return xhci_suspend(xhci, device_may_wakeup(dev));
}

static int xhci_plat_resume(struct device *dev)
{
        struct usb_hcd  *hcd = dev_get_drvdata(dev);
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);

        return xhci_resume(xhci, 0);
}

static const struct dev_pm_ops xhci_plat_pm_ops = {
        SET_SYSTEM_SLEEP_PM_OPS(xhci_plat_suspend, xhci_plat_resume)
};
#define DEV_PM_OPS      (&xhci_plat_pm_ops)
#else
#define DEV_PM_OPS      NULL
#endif /* CONFIG_PM */

#ifdef CONFIG_OF
static const struct of_device_id usb_xhci_of_match[] = {
        { .compatible = "generic-xhci" },
        { .compatible = "xhci-platform" },
        { },
};
MODULE_DEVICE_TABLE(of, usb_xhci_of_match);
#endif

static struct platform_driver usb_xhci_driver = {
        .probe  = xhci_plat_probe,
        .remove = xhci_plat_remove,
        .driver = {
                .name = "xhci-hcd",
                .pm = DEV_PM_OPS,
                .of_match_table = of_match_ptr(usb_xhci_of_match),
        },
};
MODULE_ALIAS("platform:xhci-hcd");

static int __init xhci_plat_init(void)
{
        xhci_init_driver(&xhci_plat_hc_driver, xhci_plat_setup);
        xhci_plat_hc_driver.start = xhci_plat_start;
        return platform_driver_register(&usb_xhci_driver);
}
module_init(xhci_plat_init);

static void __exit xhci_plat_exit(void)
{
        platform_driver_unregister(&usb_xhci_driver);
}
module_exit(xhci_plat_exit);

MODULE_DESCRIPTION("xHCI Platform Host Controller Driver");
MODULE_LICENSE("GPL");