/**
 * dwc3-exynos.c - Samsung EXYNOS DWC3 Specific Glue layer
 *
 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
 *              http://www.samsung.com
 *
 * Author: Anton Tikhomirov <av.tikhomirov@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/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/platform_data/dwc3-exynos.h>
#include <linux/dma-mapping.h>
#include <linux/clk.h>
#include <linux/usb/otg.h>
#include <linux/usb/nop-usb-xceiv.h>
#include <linux/of.h>
#include <linux/of_platform.h>

struct dwc3_exynos {
        struct platform_device  *usb2_phy;
        struct platform_device  *usb3_phy;
        struct device           *dev;

        struct clk              *clk;
};

static int dwc3_exynos_register_phys(struct dwc3_exynos *exynos)
{
        struct nop_usb_xceiv_platform_data pdata;
        struct platform_device  *pdev;
        int                     ret;

        memset(&pdata, 0x00, sizeof(pdata));

        pdev = platform_device_alloc("nop_usb_xceiv", PLATFORM_DEVID_AUTO);
        if (!pdev)
                return -ENOMEM;

        exynos->usb2_phy = pdev;
        pdata.type = USB_PHY_TYPE_USB2;

        ret = platform_device_add_data(exynos->usb2_phy, &pdata, sizeof(pdata));
        if (ret)
                goto err1;

        pdev = platform_device_alloc("nop_usb_xceiv", PLATFORM_DEVID_AUTO);
        if (!pdev) {
                ret = -ENOMEM;
                goto err1;
        }

        exynos->usb3_phy = pdev;
        pdata.type = USB_PHY_TYPE_USB3;

        ret = platform_device_add_data(exynos->usb3_phy, &pdata, sizeof(pdata));
        if (ret)
                goto err2;

        ret = platform_device_add(exynos->usb2_phy);
        if (ret)
                goto err2;

        ret = platform_device_add(exynos->usb3_phy);
        if (ret)
                goto err3;

        return 0;

err3:
        platform_device_del(exynos->usb2_phy);

err2:
        platform_device_put(exynos->usb3_phy);

err1:
        platform_device_put(exynos->usb2_phy);

        return ret;
}

static int dwc3_exynos_remove_child(struct device *dev, void *unused)
{
        struct platform_device *pdev = to_platform_device(dev);

        platform_device_unregister(pdev);

        return 0;
}

static int dwc3_exynos_probe(struct platform_device *pdev)
{
        struct dwc3_exynos      *exynos;
        struct clk              *clk;
        struct device           *dev = &pdev->dev;
        struct device_node      *node = dev->of_node;

        int                     ret = -ENOMEM;

        exynos = devm_kzalloc(dev, sizeof(*exynos), GFP_KERNEL);
        if (!exynos) {
                dev_err(dev, "not enough memory\n");
                goto err1;
        }

        /*
         * 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.
         */
        if (!dev->dma_mask)
                dev->dma_mask = &dev->coherent_dma_mask;
        if (!dev->coherent_dma_mask)
                dev->coherent_dma_mask = DMA_BIT_MASK(32);

        platform_set_drvdata(pdev, exynos);

        ret = dwc3_exynos_register_phys(exynos);
        if (ret) {
                dev_err(dev, "couldn't register PHYs\n");
                goto err1;
        }

        clk = devm_clk_get(dev, "usbdrd30");
        if (IS_ERR(clk)) {
                dev_err(dev, "couldn't get clock\n");
                ret = -EINVAL;
                goto err1;
        }

        exynos->dev     = dev;
        exynos->clk     = clk;

        clk_prepare_enable(exynos->clk);

        if (node) {
                ret = of_platform_populate(node, NULL, NULL, dev);
                if (ret) {
                        dev_err(dev, "failed to add dwc3 core\n");
                        goto err2;
                }
        } else {
                dev_err(dev, "no device node, failed to add dwc3 core\n");
                ret = -ENODEV;
                goto err2;
        }

        return 0;

err2:
        clk_disable_unprepare(clk);
err1:
        return ret;
}

static int dwc3_exynos_remove(struct platform_device *pdev)
{
        struct dwc3_exynos      *exynos = platform_get_drvdata(pdev);

        device_for_each_child(&pdev->dev, NULL, dwc3_exynos_remove_child);
        platform_device_unregister(exynos->usb2_phy);
        platform_device_unregister(exynos->usb3_phy);

        clk_disable_unprepare(exynos->clk);

        return 0;
}

#ifdef CONFIG_OF
static const struct of_device_id exynos_dwc3_match[] = {
        { .compatible = "samsung,exynos5250-dwusb3" },
        {},
};
MODULE_DEVICE_TABLE(of, exynos_dwc3_match);
#endif

#ifdef CONFIG_PM_SLEEP
static int dwc3_exynos_suspend(struct device *dev)
{
        struct dwc3_exynos *exynos = dev_get_drvdata(dev);

        clk_disable(exynos->clk);

        return 0;
}

static int dwc3_exynos_resume(struct device *dev)
{
        struct dwc3_exynos *exynos = dev_get_drvdata(dev);

        clk_enable(exynos->clk);

        /* runtime set active to reflect active state. */
        pm_runtime_disable(dev);
        pm_runtime_set_active(dev);
        pm_runtime_enable(dev);

        return 0;
}

static const struct dev_pm_ops dwc3_exynos_dev_pm_ops = {
        SET_SYSTEM_SLEEP_PM_OPS(dwc3_exynos_suspend, dwc3_exynos_resume)
};

#define DEV_PM_OPS      (&dwc3_exynos_dev_pm_ops)
#else
#define DEV_PM_OPS      NULL
#endif /* CONFIG_PM_SLEEP */

static struct platform_driver dwc3_exynos_driver = {
        .probe          = dwc3_exynos_probe,
        .remove         = dwc3_exynos_remove,
        .driver         = {
                .name   = "exynos-dwc3",
                .of_match_table = of_match_ptr(exynos_dwc3_match),
                .pm     = DEV_PM_OPS,
        },
};

module_platform_driver(dwc3_exynos_driver);

MODULE_ALIAS("platform:exynos-dwc3");
MODULE_AUTHOR("Anton Tikhomirov <av.tikhomirov@samsung.com>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("DesignWare USB3 EXYNOS Glue Layer");