// SPDX-License-Identifier: GPL-2.0
/*
 * dwc3-imx8mp.c - NXP imx8mp Specific Glue layer
 *
 * Copyright (c) 2020 NXP.
 */

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

#include "core.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_imx8mp {
        struct device                   *dev;
        struct platform_device          *dwc3_pdev;
        void __iomem                    *hsio_blk_base;
        void __iomem                    *glue_base;
        struct clk                      *hsio_clk;
        struct clk                      *suspend_clk;
        int                             irq;
        bool                            pm_suspended;
        bool                            wakeup_pending;
};

static void imx8mp_configure_glue(struct dwc3_imx8mp *dwc3_imx)
{
        struct device *dev = dwc3_imx->dev;
        u32 value;

        if (!dwc3_imx->glue_base)
                return;

        value = readl(dwc3_imx->glue_base + USB_CTRL0);

        if (device_property_read_bool(dev, "fsl,permanently-attached"))
                value |= (USB_CTRL0_USB2_FIXED | USB_CTRL0_USB3_FIXED);
        else
                value &= ~(USB_CTRL0_USB2_FIXED | USB_CTRL0_USB3_FIXED);

        if (device_property_read_bool(dev, "fsl,disable-port-power-control"))
                value &= ~(USB_CTRL0_PORTPWR_EN);
        else
                value |= USB_CTRL0_PORTPWR_EN;

        writel(value, dwc3_imx->glue_base + USB_CTRL0);

        value = readl(dwc3_imx->glue_base + USB_CTRL1);
        if (device_property_read_bool(dev, "fsl,over-current-active-low"))
                value |= USB_CTRL1_OC_POLARITY;
        else
                value &= ~USB_CTRL1_OC_POLARITY;

        if (device_property_read_bool(dev, "fsl,power-active-low"))
                value |= USB_CTRL1_PWR_POLARITY;
        else
                value &= ~USB_CTRL1_PWR_POLARITY;

        writel(value, dwc3_imx->glue_base + USB_CTRL1);
}

static void dwc3_imx8mp_wakeup_enable(struct dwc3_imx8mp *dwc3_imx,
                                      pm_message_t msg)
{
        struct dwc3     *dwc3 = platform_get_drvdata(dwc3_imx->dwc3_pdev);
        u32             val;

        if (!dwc3)
                return;

        val = readl(dwc3_imx->hsio_blk_base + USB_WAKEUP_CTRL);

        if ((dwc3->current_dr_role == DWC3_GCTL_PRTCAP_HOST) && dwc3->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, dwc3_imx->hsio_blk_base + USB_WAKEUP_CTRL);
}

static void dwc3_imx8mp_wakeup_disable(struct dwc3_imx8mp *dwc3_imx)
{
        u32 val;

        val = readl(dwc3_imx->hsio_blk_base + USB_WAKEUP_CTRL);
        val &= ~(USB_WAKEUP_EN | USB_WAKEUP_EN_MASK);
        writel(val, dwc3_imx->hsio_blk_base + USB_WAKEUP_CTRL);
}

static const struct property_entry dwc3_imx8mp_properties[] = {
        PROPERTY_ENTRY_BOOL("xhci-missing-cas-quirk"),
        PROPERTY_ENTRY_BOOL("xhci-skip-phy-init-quirk"),
        {},
};

static const struct software_node dwc3_imx8mp_swnode = {
        .properties = dwc3_imx8mp_properties,
};

static irqreturn_t dwc3_imx8mp_interrupt(int irq, void *_dwc3_imx)
{
        struct dwc3_imx8mp      *dwc3_imx = _dwc3_imx;
        struct dwc3             *dwc = platform_get_drvdata(dwc3_imx->dwc3_pdev);

        if (!dwc3_imx->pm_suspended)
                return IRQ_HANDLED;

        disable_irq_nosync(dwc3_imx->irq);
        dwc3_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);
}

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

static int dwc3_imx8mp_probe(struct platform_device *pdev)
{
        struct device           *dev = &pdev->dev;
        struct device_node      *node = dev->of_node;
        struct dwc3_imx8mp      *dwc3_imx;
        struct dwc3             *dwc3;
        struct resource         *res;
        int                     err, irq;

        if (!node) {
                dev_err(dev, "device node not found\n");
                return -EINVAL;
        }

        dwc3_imx = devm_kzalloc(dev, sizeof(*dwc3_imx), GFP_KERNEL);
        if (!dwc3_imx)
                return -ENOMEM;

        platform_set_drvdata(pdev, dwc3_imx);

        dwc3_imx->dev = dev;

        dwc3_imx->hsio_blk_base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(dwc3_imx->hsio_blk_base))
                return PTR_ERR(dwc3_imx->hsio_blk_base);

        res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
        if (!res) {
                dev_warn(dev, "Base address for glue layer missing. Continuing without, some features are missing though.");
        } else {
                dwc3_imx->glue_base = devm_ioremap_resource(dev, res);
                if (IS_ERR(dwc3_imx->glue_base))
                        return PTR_ERR(dwc3_imx->glue_base);
        }

        dwc3_imx->hsio_clk = devm_clk_get_enabled(dev, "hsio");
        if (IS_ERR(dwc3_imx->hsio_clk))
                return dev_err_probe(dev, PTR_ERR(dwc3_imx->hsio_clk),
                                     "Failed to get hsio clk\n");

        dwc3_imx->suspend_clk = devm_clk_get_enabled(dev, "suspend");
        if (IS_ERR(dwc3_imx->suspend_clk))
                return dev_err_probe(dev, PTR_ERR(dwc3_imx->suspend_clk),
                                     "Failed to get suspend clk\n");

        irq = platform_get_irq(pdev, 0);
        if (irq < 0)
                return irq;
        dwc3_imx->irq = irq;

        struct device_node *dwc3_np __free(device_node) = of_get_compatible_child(node,
                                                                                  "snps,dwc3");
        if (!dwc3_np)
                return dev_err_probe(dev, -ENODEV, "failed to find dwc3 core child\n");

        imx8mp_configure_glue(dwc3_imx);

        pm_runtime_set_active(dev);
        pm_runtime_enable(dev);
        err = pm_runtime_get_sync(dev);
        if (err < 0)
                goto disable_rpm;

        err = device_add_software_node(dev, &dwc3_imx8mp_swnode);
        if (err) {
                err = -ENODEV;
                dev_err(dev, "failed to add software node\n");
                goto disable_rpm;
        }

        err = of_platform_populate(node, NULL, NULL, dev);
        if (err) {
                dev_err(&pdev->dev, "failed to create dwc3 core\n");
                goto remove_swnode;
        }

        dwc3_imx->dwc3_pdev = of_find_device_by_node(dwc3_np);
        if (!dwc3_imx->dwc3_pdev) {
                dev_err(dev, "failed to get dwc3 platform device\n");
                err = -ENODEV;
                goto depopulate;
        }

        dwc3 = platform_get_drvdata(dwc3_imx->dwc3_pdev);
        if (!dwc3) {
                err = dev_err_probe(dev, -EPROBE_DEFER, "failed to get dwc3 platform data\n");
                goto put_dwc3;
        }

        dwc3->glue_ops = &dwc3_imx_glue_ops;

        if (dwc3->dr_mode == USB_DR_MODE_HOST)
                pm_runtime_dont_use_autosuspend(dwc3->dev);

        err = devm_request_threaded_irq(dev, irq, NULL, dwc3_imx8mp_interrupt,
                                        IRQF_ONESHOT, dev_name(dev), dwc3_imx);
        if (err) {
                dev_err(dev, "failed to request IRQ #%d --> %d\n", irq, err);
                goto put_dwc3;
        }

        device_set_wakeup_capable(dev, true);
        pm_runtime_put(dev);

        return 0;

put_dwc3:
        put_device(&dwc3_imx->dwc3_pdev->dev);
depopulate:
        of_platform_depopulate(dev);
remove_swnode:
        device_remove_software_node(dev);
disable_rpm:
        pm_runtime_disable(dev);
        pm_runtime_put_noidle(dev);

        return err;
}

static void dwc3_imx8mp_remove(struct platform_device *pdev)
{
        struct dwc3_imx8mp *dwc3_imx = platform_get_drvdata(pdev);
        struct device *dev = &pdev->dev;

        put_device(&dwc3_imx->dwc3_pdev->dev);

        pm_runtime_get_sync(dev);
        of_platform_depopulate(dev);
        device_remove_software_node(dev);

        pm_runtime_disable(dev);
        pm_runtime_put_noidle(dev);
}

static int dwc3_imx8mp_suspend(struct dwc3_imx8mp *dwc3_imx, pm_message_t msg)
{
        if (dwc3_imx->pm_suspended)
                return 0;

        /* Wakeup enable */
        if (PMSG_IS_AUTO(msg) || device_may_wakeup(dwc3_imx->dev))
                dwc3_imx8mp_wakeup_enable(dwc3_imx, msg);

        dwc3_imx->pm_suspended = true;

        return 0;
}

static int dwc3_imx8mp_resume(struct dwc3_imx8mp *dwc3_imx, pm_message_t msg)
{
        struct dwc3     *dwc = platform_get_drvdata(dwc3_imx->dwc3_pdev);
        int ret = 0;

        if (!dwc3_imx->pm_suspended)
                return 0;

        /* Wakeup disable */
        dwc3_imx8mp_wakeup_disable(dwc3_imx);
        dwc3_imx->pm_suspended = false;

        /* Upon power loss any previous configuration is lost, restore it */
        imx8mp_configure_glue(dwc3_imx);

        if (dwc3_imx->wakeup_pending) {
                dwc3_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);
                }
                enable_irq(dwc3_imx->irq);
        }

        return ret;
}

static int dwc3_imx8mp_pm_suspend(struct device *dev)
{
        struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);
        int ret;

        ret = dwc3_imx8mp_suspend(dwc3_imx, PMSG_SUSPEND);

        if (device_may_wakeup(dwc3_imx->dev)) {
                enable_irq_wake(dwc3_imx->irq);

                if (device_is_compatible(dev, "fsl,imx95-dwc3"))
                        device_set_out_band_wakeup(dev);

        } else {
                clk_disable_unprepare(dwc3_imx->suspend_clk);
        }

        clk_disable_unprepare(dwc3_imx->hsio_clk);
        dev_dbg(dev, "dwc3 imx8mp pm suspend.\n");

        return ret;
}

static int dwc3_imx8mp_pm_resume(struct device *dev)
{
        struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);
        int ret;

        if (device_may_wakeup(dwc3_imx->dev)) {
                disable_irq_wake(dwc3_imx->irq);
        } else {
                ret = clk_prepare_enable(dwc3_imx->suspend_clk);
                if (ret)
                        return ret;
        }

        ret = clk_prepare_enable(dwc3_imx->hsio_clk);
        if (ret) {
                clk_disable_unprepare(dwc3_imx->suspend_clk);
                return ret;
        }

        ret = dwc3_imx8mp_resume(dwc3_imx, PMSG_RESUME);

        pm_runtime_disable(dev);
        pm_runtime_set_active(dev);
        pm_runtime_enable(dev);

        dev_dbg(dev, "dwc3 imx8mp pm resume.\n");

        return ret;
}

static int dwc3_imx8mp_runtime_suspend(struct device *dev)
{
        struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);

        dev_dbg(dev, "dwc3 imx8mp runtime suspend.\n");

        return dwc3_imx8mp_suspend(dwc3_imx, PMSG_AUTO_SUSPEND);
}

static int dwc3_imx8mp_runtime_resume(struct device *dev)
{
        struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);

        dev_dbg(dev, "dwc3 imx8mp runtime resume.\n");

        return dwc3_imx8mp_resume(dwc3_imx, PMSG_AUTO_RESUME);
}

static const struct dev_pm_ops dwc3_imx8mp_dev_pm_ops = {
        SYSTEM_SLEEP_PM_OPS(dwc3_imx8mp_pm_suspend, dwc3_imx8mp_pm_resume)
        RUNTIME_PM_OPS(dwc3_imx8mp_runtime_suspend, dwc3_imx8mp_runtime_resume,
                       NULL)
};

static const struct of_device_id dwc3_imx8mp_of_match[] = {
        { .compatible = "fsl,imx8mp-dwc3", },
        {},
};
MODULE_DEVICE_TABLE(of, dwc3_imx8mp_of_match);

static struct platform_driver dwc3_imx8mp_driver = {
        .probe          = dwc3_imx8mp_probe,
        .remove         = dwc3_imx8mp_remove,
        .driver         = {
                .name   = "imx8mp-dwc3",
                .pm     = pm_ptr(&dwc3_imx8mp_dev_pm_ops),
                .of_match_table = dwc3_imx8mp_of_match,
        },
};

module_platform_driver(dwc3_imx8mp_driver);

MODULE_ALIAS("platform:imx8mp-dwc3");
MODULE_AUTHOR("jun.li@nxp.com");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("DesignWare USB3 imx8mp Glue Layer");