// SPDX-License-Identifier: GPL-2.0
/*
 * dwc3-imx.c - NXP i.MX Soc USB3 Specific Glue layer
 *
 * Copyright 2026 NXP
 */

#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>

#include "core.h"
#include "glue.h"

/* USB wakeup registers */
#define USB_WAKEUP_CTRL                 0x00

/* Global wakeup interrupt enable, also used to clear interrupt */
#define USB_WAKEUP_EN                   BIT(31)
/* Wakeup from connect or disconnect, only for superspeed */
#define USB_WAKEUP_SS_CONN              BIT(5)
/* 0 select vbus_valid, 1 select sessvld */
#define USB_WAKEUP_VBUS_SRC_SESS_VAL    BIT(4)
/* Enable signal for wake up from u3 state */
#define USB_WAKEUP_U3_EN                BIT(3)
/* Enable signal for wake up from id change */
#define USB_WAKEUP_ID_EN                BIT(2)
/* Enable signal for wake up from vbus change */
#define USB_WAKEUP_VBUS_EN              BIT(1)
/* Enable signal for wake up from dp/dm change */
#define USB_WAKEUP_DPDM_EN              BIT(0)

#define USB_WAKEUP_EN_MASK              GENMASK(5, 0)

/* USB glue registers */
#define USB_CTRL0               0x00
#define USB_CTRL1               0x04

#define USB_CTRL0_PORTPWR_EN    BIT(12) /* 1 - PPC enabled (default) */
#define USB_CTRL0_USB3_FIXED    BIT(22) /* 1 - USB3 permanent attached */
#define USB_CTRL0_USB2_FIXED    BIT(23) /* 1 - USB2 permanent attached */

#define USB_CTRL1_OC_POLARITY   BIT(16) /* 0 - HIGH / 1 - LOW */
#define USB_CTRL1_PWR_POLARITY  BIT(17) /* 0 - HIGH / 1 - LOW */

struct dwc3_imx {
        struct dwc3     dwc;
        struct device   *dev;
        void __iomem    *blkctl_base;
        void __iomem    *glue_base;
        struct clk      *hsio_clk;
        struct clk      *suspend_clk;
        int             irq;
        bool            pm_suspended;
        bool            wakeup_pending;
        unsigned        permanent_attached:1;
        unsigned        disable_pwr_ctrl:1;
        unsigned        overcur_active_low:1;
        unsigned        power_active_low:1;
};

#define to_dwc3_imx(d) container_of((d), struct dwc3_imx, dwc)

static void dwc3_imx_get_property(struct dwc3_imx *dwc_imx)
{
        struct device   *dev = dwc_imx->dev;

        dwc_imx->permanent_attached =
                device_property_read_bool(dev, "fsl,permanently-attached");
        dwc_imx->disable_pwr_ctrl =
                device_property_read_bool(dev, "fsl,disable-port-power-control");
        dwc_imx->overcur_active_low =
                device_property_read_bool(dev, "fsl,over-current-active-low");
        dwc_imx->power_active_low =
                device_property_read_bool(dev, "fsl,power-active-low");
}

static void dwc3_imx_configure_glue(struct dwc3_imx *dwc_imx)
{
        u32             value;

        if (!dwc_imx->glue_base)
                return;

        value = readl(dwc_imx->glue_base + USB_CTRL0);

        if (dwc_imx->permanent_attached)
                value |= USB_CTRL0_USB2_FIXED | USB_CTRL0_USB3_FIXED;
        else
                value &= ~(USB_CTRL0_USB2_FIXED | USB_CTRL0_USB3_FIXED);

        if (dwc_imx->disable_pwr_ctrl)
                value &= ~USB_CTRL0_PORTPWR_EN;
        else
                value |= USB_CTRL0_PORTPWR_EN;

        writel(value, dwc_imx->glue_base + USB_CTRL0);

        value = readl(dwc_imx->glue_base + USB_CTRL1);
        if (dwc_imx->overcur_active_low)
                value |= USB_CTRL1_OC_POLARITY;
        else
                value &= ~USB_CTRL1_OC_POLARITY;

        if (dwc_imx->power_active_low)
                value |= USB_CTRL1_PWR_POLARITY;
        else
                value &= ~USB_CTRL1_PWR_POLARITY;

        writel(value, dwc_imx->glue_base + USB_CTRL1);
}

static void dwc3_imx_wakeup_enable(struct dwc3_imx *dwc_imx, pm_message_t msg)
{
        struct dwc3     *dwc = &dwc_imx->dwc;
        u32             val;

        val = readl(dwc_imx->blkctl_base + USB_WAKEUP_CTRL);

        if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_HOST && dwc->xhci) {
                val |= USB_WAKEUP_EN | USB_WAKEUP_DPDM_EN;
                if (PMSG_IS_AUTO(msg))
                        val |= USB_WAKEUP_SS_CONN | USB_WAKEUP_U3_EN;
        } else {
                val |= USB_WAKEUP_EN | USB_WAKEUP_VBUS_EN |
                       USB_WAKEUP_VBUS_SRC_SESS_VAL;
        }

        writel(val, dwc_imx->blkctl_base + USB_WAKEUP_CTRL);
}

static void dwc3_imx_wakeup_disable(struct dwc3_imx *dwc_imx)
{
        u32     val;

        val = readl(dwc_imx->blkctl_base + USB_WAKEUP_CTRL);
        val &= ~(USB_WAKEUP_EN | USB_WAKEUP_EN_MASK);
        writel(val, dwc_imx->blkctl_base + USB_WAKEUP_CTRL);
}

static irqreturn_t dwc3_imx_interrupt(int irq, void *data)
{
        struct dwc3_imx *dwc_imx = data;
        struct dwc3     *dwc = &dwc_imx->dwc;

        if (!dwc_imx->pm_suspended)
                return IRQ_HANDLED;

        disable_irq_nosync(dwc_imx->irq);
        dwc_imx->wakeup_pending = true;

        if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_HOST && dwc->xhci)
                pm_runtime_resume(&dwc->xhci->dev);
        else if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE)
                pm_runtime_get(dwc->dev);

        return IRQ_HANDLED;
}

static void dwc3_imx_pre_set_role(struct dwc3 *dwc, enum usb_role role)
{
        if (role == USB_ROLE_HOST)
                /*
                 * For xhci host, we need disable dwc core auto
                 * suspend, because during this auto suspend delay(5s),
                 * xhci host RUN_STOP is cleared and wakeup is not
                 * enabled, if device is inserted, xhci host can't
                 * response the connection.
                 */
                pm_runtime_dont_use_autosuspend(dwc->dev);
        else
                pm_runtime_use_autosuspend(dwc->dev);
}

static struct dwc3_glue_ops dwc3_imx_glue_ops = {
        .pre_set_role = dwc3_imx_pre_set_role,
};

static const struct property_entry dwc3_imx_properties[] = {
        PROPERTY_ENTRY_BOOL("xhci-missing-cas-quirk"),
        PROPERTY_ENTRY_BOOL("xhci-skip-phy-init-quirk"),
        {},
};

static const struct software_node dwc3_imx_swnode = {
        .properties = dwc3_imx_properties,
};

static int dwc3_imx_probe(struct platform_device *pdev)
{
        struct device           *dev = &pdev->dev;
        struct dwc3_imx         *dwc_imx;
        struct dwc3             *dwc;
        struct resource         *res;
        const char              *irq_name;
        struct dwc3_probe_data  probe_data = {};
        int                     ret, irq;

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

        platform_set_drvdata(pdev, dwc_imx);
        dwc_imx->dev = dev;

        dwc3_imx_get_property(dwc_imx);

        dwc_imx->blkctl_base = devm_platform_ioremap_resource_byname(pdev, "blkctl");
        if (IS_ERR(dwc_imx->blkctl_base))
                return PTR_ERR(dwc_imx->blkctl_base);

        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "glue");
        if (!res) {
                dev_warn(dev, "Base address for glue layer missing\n");
        } else {
                dwc_imx->glue_base = devm_ioremap_resource(dev, res);
                if (IS_ERR(dwc_imx->glue_base))
                        return PTR_ERR(dwc_imx->glue_base);
        }

        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "core");
        if (!res)
                return dev_err_probe(dev, -ENODEV, "missing core memory resource\n");

        dwc_imx->hsio_clk = devm_clk_get_enabled(dev, "hsio");
        if (IS_ERR(dwc_imx->hsio_clk))
                return dev_err_probe(dev, PTR_ERR(dwc_imx->hsio_clk),
                                     "Failed to get hsio clk\n");

        dwc_imx->suspend_clk = devm_clk_get_enabled(dev, "suspend");
        if (IS_ERR(dwc_imx->suspend_clk))
                return dev_err_probe(dev, PTR_ERR(dwc_imx->suspend_clk),
                                     "Failed to get suspend clk\n");

        irq = platform_get_irq_byname(pdev, "wakeup");
        if (irq < 0)
                return irq;
        dwc_imx->irq = irq;

        irq_name = devm_kasprintf(dev, GFP_KERNEL, "%s:wakeup", dev_name(dev));
        if (!irq_name)
                return dev_err_probe(dev, -ENOMEM, "failed to create irq_name\n");

        ret = devm_request_threaded_irq(dev, irq, NULL, dwc3_imx_interrupt,
                                        IRQF_ONESHOT | IRQF_NO_AUTOEN,
                                        irq_name, dwc_imx);
        if (ret)
                return dev_err_probe(dev, ret, "failed to request IRQ #%d\n", irq);

        ret = device_add_software_node(dev, &dwc3_imx_swnode);
        if (ret)
                return dev_err_probe(dev, ret, "failed to add software node\n");

        dwc3_imx_configure_glue(dwc_imx);

        dwc = &dwc_imx->dwc;
        dwc->dev = dev;
        dwc->glue_ops = &dwc3_imx_glue_ops;

        probe_data.res = res;
        probe_data.dwc = dwc;
        probe_data.properties = DWC3_DEFAULT_PROPERTIES;
        probe_data.properties.needs_full_reinit = true;

        ret = dwc3_core_probe(&probe_data);
        if (ret) {
                device_remove_software_node(dev);
                return ret;
        }

        device_set_wakeup_capable(dev, true);
        return 0;
}

static void dwc3_imx_remove(struct platform_device *pdev)
{
        struct device   *dev = &pdev->dev;
        struct dwc3     *dwc = dev_get_drvdata(dev);

        dwc3_core_remove(dwc);
        device_remove_software_node(dev);
}

static void dwc3_imx_suspend(struct dwc3_imx *dwc_imx, pm_message_t msg)
{
        if (dwc_imx->pm_suspended)
                return;

        if (PMSG_IS_AUTO(msg) || device_may_wakeup(dwc_imx->dev))
                dwc3_imx_wakeup_enable(dwc_imx, msg);

        enable_irq(dwc_imx->irq);
        dwc_imx->pm_suspended = true;
}

static void dwc3_imx_resume(struct dwc3_imx *dwc_imx, pm_message_t msg)
{
        struct dwc3     *dwc = &dwc_imx->dwc;

        if (!dwc_imx->pm_suspended)
                return;

        dwc_imx->pm_suspended = false;
        if (!dwc_imx->wakeup_pending)
                disable_irq_nosync(dwc_imx->irq);

        dwc3_imx_wakeup_disable(dwc_imx);

        /* Upon power loss any previous configuration is lost, restore it */
        dwc3_imx_configure_glue(dwc_imx);

        if (dwc_imx->wakeup_pending) {
                dwc_imx->wakeup_pending = false;
                if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE)
                        pm_runtime_put_autosuspend(dwc->dev);
                else
                        /*
                         * Add wait for xhci switch from suspend
                         * clock to normal clock to detect connection.
                         */
                        usleep_range(9000, 10000);
        }
}

static int dwc3_imx_runtime_suspend(struct device *dev)
{
        struct dwc3     *dwc = dev_get_drvdata(dev);
        struct dwc3_imx *dwc_imx = to_dwc3_imx(dwc);
        int             ret;

        ret = dwc3_runtime_suspend(dwc);
        if (ret)
                return ret;

        dwc3_imx_suspend(dwc_imx, PMSG_AUTO_SUSPEND);
        return 0;
}

static int dwc3_imx_runtime_resume(struct device *dev)
{
        struct dwc3     *dwc = dev_get_drvdata(dev);
        struct dwc3_imx *dwc_imx = to_dwc3_imx(dwc);

        dwc3_imx_resume(dwc_imx, PMSG_AUTO_RESUME);
        return dwc3_runtime_resume(dwc);
}

static int dwc3_imx_runtime_idle(struct device *dev)
{
        return dwc3_runtime_idle(dev_get_drvdata(dev));
}

static int dwc3_imx_pm_suspend(struct device *dev)
{
        struct dwc3     *dwc = dev_get_drvdata(dev);
        struct dwc3_imx *dwc_imx = to_dwc3_imx(dwc);
        int             ret;

        ret = dwc3_pm_suspend(dwc);
        if (ret)
                return ret;

        dwc3_imx_suspend(dwc_imx, PMSG_SUSPEND);

        if (device_may_wakeup(dev)) {
                enable_irq_wake(dwc_imx->irq);
                device_set_out_band_wakeup(dev);
        } else {
                clk_disable_unprepare(dwc_imx->suspend_clk);
        }

        clk_disable_unprepare(dwc_imx->hsio_clk);

        return 0;
}

static int dwc3_imx_pm_resume(struct device *dev)
{
        struct dwc3     *dwc = dev_get_drvdata(dev);
        struct dwc3_imx *dwc_imx = to_dwc3_imx(dwc);
        int             ret;

        if (device_may_wakeup(dwc_imx->dev)) {
                disable_irq_wake(dwc_imx->irq);
        } else {
                ret = clk_prepare_enable(dwc_imx->suspend_clk);
                if (ret)
                        return ret;
        }

        ret = clk_prepare_enable(dwc_imx->hsio_clk);
        if (ret) {
                clk_disable_unprepare(dwc_imx->suspend_clk);
                return ret;
        }

        dwc3_imx_resume(dwc_imx, PMSG_RESUME);

        ret = dwc3_pm_resume(dwc);
        if (ret)
                return ret;

        return 0;
}

static void dwc3_imx_complete(struct device *dev)
{
        dwc3_pm_complete(dev_get_drvdata(dev));
}

static int dwc3_imx_prepare(struct device *dev)
{
        return dwc3_pm_prepare(dev_get_drvdata(dev));
}

static const struct dev_pm_ops dwc3_imx_dev_pm_ops = {
        SYSTEM_SLEEP_PM_OPS(dwc3_imx_pm_suspend, dwc3_imx_pm_resume)
        RUNTIME_PM_OPS(dwc3_imx_runtime_suspend, dwc3_imx_runtime_resume,
                       dwc3_imx_runtime_idle)
        .complete = pm_sleep_ptr(dwc3_imx_complete),
        .prepare = pm_sleep_ptr(dwc3_imx_prepare),
};

static const struct of_device_id dwc3_imx_of_match[] = {
        { .compatible = "nxp,imx8mp-dwc3", },
        {},
};
MODULE_DEVICE_TABLE(of, dwc3_imx_of_match);

static struct platform_driver dwc3_imx_driver = {
        .probe          = dwc3_imx_probe,
        .remove         = dwc3_imx_remove,
        .driver         = {
                .name   = "imx-dwc3",
                .pm     = pm_ptr(&dwc3_imx_dev_pm_ops),
                .of_match_table = dwc3_imx_of_match,
        },
};

module_platform_driver(dwc3_imx_driver);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("DesignWare USB3 i.MX Glue Layer");