// SPDX-License-Identifier: GPL-2.0+
//
// Copyright (C) 2011 Samsung Electronics Co.Ltd
// Author: Joonyoung Shim <jy0922.shim@samsung.com>

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include "map.h"
#include "cpu.h"
#include "usb-phy.h"

#include "regs-sys-s3c64xx.h"
#include "regs-usb-hsotg-phy-s3c64xx.h"

enum samsung_usb_phy_type {
        USB_PHY_TYPE_DEVICE,
        USB_PHY_TYPE_HOST,
};

static int s3c_usb_otgphy_init(struct platform_device *pdev)
{
        struct clk *xusbxti;
        u32 phyclk;

        writel(readl(S3C64XX_OTHERS) | S3C64XX_OTHERS_USBMASK, S3C64XX_OTHERS);

        /* set clock frequency for PLL */
        phyclk = readl(S3C_PHYCLK) & ~S3C_PHYCLK_CLKSEL_MASK;

        xusbxti = clk_get(&pdev->dev, "xusbxti");
        if (!IS_ERR(xusbxti)) {
                switch (clk_get_rate(xusbxti)) {
                case 12 * MHZ:
                        phyclk |= S3C_PHYCLK_CLKSEL_12M;
                        break;
                case 24 * MHZ:
                        phyclk |= S3C_PHYCLK_CLKSEL_24M;
                        break;
                default:
                case 48 * MHZ:
                        /* default reference clock */
                        break;
                }
                clk_put(xusbxti);
        }

        /* TODO: select external clock/oscillator */
        writel(phyclk | S3C_PHYCLK_CLK_FORCE, S3C_PHYCLK);

        /* set to normal OTG PHY */
        writel((readl(S3C_PHYPWR) & ~S3C_PHYPWR_NORMAL_MASK), S3C_PHYPWR);
        mdelay(1);

        /* reset OTG PHY and Link */
        writel(S3C_RSTCON_PHY | S3C_RSTCON_HCLK | S3C_RSTCON_PHYCLK,
                        S3C_RSTCON);
        udelay(20);     /* at-least 10uS */
        writel(0, S3C_RSTCON);

        return 0;
}

static int s3c_usb_otgphy_exit(struct platform_device *pdev)
{
        writel((readl(S3C_PHYPWR) | S3C_PHYPWR_ANALOG_POWERDOWN |
                                S3C_PHYPWR_OTG_DISABLE), S3C_PHYPWR);

        writel(readl(S3C64XX_OTHERS) & ~S3C64XX_OTHERS_USBMASK, S3C64XX_OTHERS);

        return 0;
}

int s3c_usb_phy_init(struct platform_device *pdev, int type)
{
        if (type == USB_PHY_TYPE_DEVICE)
                return s3c_usb_otgphy_init(pdev);

        return -EINVAL;
}

int s3c_usb_phy_exit(struct platform_device *pdev, int type)
{
        if (type == USB_PHY_TYPE_DEVICE)
                return s3c_usb_otgphy_exit(pdev);

        return -EINVAL;
}