// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Allwinner sun9i USB phy driver
 *
 * Copyright (C) 2014-2015 Chen-Yu Tsai <wens@csie.org>
 *
 * Based on phy-sun4i-usb.c from
 * Hans de Goede <hdegoede@redhat.com>
 *
 * and code from
 * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
 */

#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/phy/phy.h>
#include <linux/usb/of.h>
#include <linux/platform_device.h>
#include <linux/reset.h>

#define SUNXI_AHB_INCR16_BURST_EN       BIT(11)
#define SUNXI_AHB_INCR8_BURST_EN        BIT(10)
#define SUNXI_AHB_INCR4_BURST_EN        BIT(9)
#define SUNXI_AHB_INCRX_ALIGN_EN        BIT(8)
#define SUNXI_ULPI_BYPASS_EN            BIT(0)

/* usb1 HSIC specific bits */
#define SUNXI_EHCI_HS_FORCE             BIT(20)
#define SUNXI_HSIC_CONNECT_DET          BIT(17)
#define SUNXI_HSIC_CONNECT_INT          BIT(16)
#define SUNXI_HSIC                      BIT(1)

struct sun9i_usb_phy {
        struct phy *phy;
        void __iomem *pmu;
        struct reset_control *reset;
        struct clk *clk;
        struct clk *hsic_clk;
        enum usb_phy_interface type;
};

static void sun9i_usb_phy_passby(struct sun9i_usb_phy *phy, int enable)
{
        u32 bits, reg_value;

        bits = SUNXI_AHB_INCR16_BURST_EN | SUNXI_AHB_INCR8_BURST_EN |
                SUNXI_AHB_INCR4_BURST_EN | SUNXI_AHB_INCRX_ALIGN_EN |
                SUNXI_ULPI_BYPASS_EN;

        if (phy->type == USBPHY_INTERFACE_MODE_HSIC)
                bits |= SUNXI_HSIC | SUNXI_EHCI_HS_FORCE |
                        SUNXI_HSIC_CONNECT_DET | SUNXI_HSIC_CONNECT_INT;

        reg_value = readl(phy->pmu);

        if (enable)
                reg_value |= bits;
        else
                reg_value &= ~bits;

        writel(reg_value, phy->pmu);
}

static int sun9i_usb_phy_init(struct phy *_phy)
{
        struct sun9i_usb_phy *phy = phy_get_drvdata(_phy);
        int ret;

        ret = clk_prepare_enable(phy->clk);
        if (ret)
                goto err_clk;

        ret = clk_prepare_enable(phy->hsic_clk);
        if (ret)
                goto err_hsic_clk;

        ret = reset_control_deassert(phy->reset);
        if (ret)
                goto err_reset;

        sun9i_usb_phy_passby(phy, 1);
        return 0;

err_reset:
        clk_disable_unprepare(phy->hsic_clk);

err_hsic_clk:
        clk_disable_unprepare(phy->clk);

err_clk:
        return ret;
}

static int sun9i_usb_phy_exit(struct phy *_phy)
{
        struct sun9i_usb_phy *phy = phy_get_drvdata(_phy);

        sun9i_usb_phy_passby(phy, 0);
        reset_control_assert(phy->reset);
        clk_disable_unprepare(phy->hsic_clk);
        clk_disable_unprepare(phy->clk);

        return 0;
}

static const struct phy_ops sun9i_usb_phy_ops = {
        .init           = sun9i_usb_phy_init,
        .exit           = sun9i_usb_phy_exit,
        .owner          = THIS_MODULE,
};

static int sun9i_usb_phy_probe(struct platform_device *pdev)
{
        struct sun9i_usb_phy *phy;
        struct device *dev = &pdev->dev;
        struct device_node *np = dev->of_node;
        struct phy_provider *phy_provider;

        phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
        if (!phy)
                return -ENOMEM;

        phy->type = of_usb_get_phy_mode(np);
        if (phy->type == USBPHY_INTERFACE_MODE_HSIC) {
                phy->clk = devm_clk_get(dev, "hsic_480M");
                if (IS_ERR(phy->clk)) {
                        dev_err(dev, "failed to get hsic_480M clock\n");
                        return PTR_ERR(phy->clk);
                }

                phy->hsic_clk = devm_clk_get(dev, "hsic_12M");
                if (IS_ERR(phy->hsic_clk)) {
                        dev_err(dev, "failed to get hsic_12M clock\n");
                        return PTR_ERR(phy->hsic_clk);
                }

                phy->reset = devm_reset_control_get(dev, "hsic");
                if (IS_ERR(phy->reset)) {
                        dev_err(dev, "failed to get reset control\n");
                        return PTR_ERR(phy->reset);
                }
        } else {
                phy->clk = devm_clk_get(dev, "phy");
                if (IS_ERR(phy->clk)) {
                        dev_err(dev, "failed to get phy clock\n");
                        return PTR_ERR(phy->clk);
                }

                phy->reset = devm_reset_control_get(dev, "phy");
                if (IS_ERR(phy->reset)) {
                        dev_err(dev, "failed to get reset control\n");
                        return PTR_ERR(phy->reset);
                }
        }

        phy->pmu = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(phy->pmu))
                return PTR_ERR(phy->pmu);

        phy->phy = devm_phy_create(dev, NULL, &sun9i_usb_phy_ops);
        if (IS_ERR(phy->phy)) {
                dev_err(dev, "failed to create PHY\n");
                return PTR_ERR(phy->phy);
        }

        phy_set_drvdata(phy->phy, phy);
        phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);

        return PTR_ERR_OR_ZERO(phy_provider);
}

static const struct of_device_id sun9i_usb_phy_of_match[] = {
        { .compatible = "allwinner,sun9i-a80-usb-phy" },
        { },
};
MODULE_DEVICE_TABLE(of, sun9i_usb_phy_of_match);

static struct platform_driver sun9i_usb_phy_driver = {
        .probe  = sun9i_usb_phy_probe,
        .driver = {
                .of_match_table = sun9i_usb_phy_of_match,
                .name  = "sun9i-usb-phy",
        }
};
module_platform_driver(sun9i_usb_phy_driver);

MODULE_DESCRIPTION("Allwinner sun9i USB phy driver");
MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>");
MODULE_LICENSE("GPL");