// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2016 MediaTek Inc.
 *
 * Author: Chunfeng Yun <chunfeng.yun@mediatek.com>
 */

#include <linux/dma-mapping.h>
#include <linux/iopoll.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/pm_wakeirq.h>
#include <linux/reset.h>

#include "mtu3.h"
#include "mtu3_dr.h"
#include "mtu3_debug.h"

/* u2-port0 should be powered on and enabled; */
int ssusb_check_clocks(struct ssusb_mtk *ssusb, u32 ex_clks)
{
        void __iomem *ibase = ssusb->ippc_base;
        u32 value, check_val;
        int ret;

        check_val = ex_clks | SSUSB_SYS125_RST_B_STS | SSUSB_SYSPLL_STABLE |
                        SSUSB_REF_RST_B_STS;

        ret = readl_poll_timeout(ibase + U3D_SSUSB_IP_PW_STS1, value,
                        (check_val == (value & check_val)), 100, 20000);
        if (ret) {
                dev_err(ssusb->dev, "clks of sts1 are not stable!\n");
                return ret;
        }

        ret = readl_poll_timeout(ibase + U3D_SSUSB_IP_PW_STS2, value,
                        (value & SSUSB_U2_MAC_SYS_RST_B_STS), 100, 10000);
        if (ret) {
                dev_err(ssusb->dev, "mac2 clock is not stable\n");
                return ret;
        }

        return 0;
}

static int wait_for_ip_sleep(struct ssusb_mtk *ssusb)
{
        bool sleep_check = true;
        u32 value;
        int ret;

        if (!ssusb->is_host)
                sleep_check = ssusb_gadget_ip_sleep_check(ssusb);

        if (!sleep_check)
                return 0;

        /* wait for ip enter sleep mode */
        ret = readl_poll_timeout(ssusb->ippc_base + U3D_SSUSB_IP_PW_STS1, value,
                                 (value & SSUSB_IP_SLEEP_STS), 100, 100000);
        if (ret) {
                dev_err(ssusb->dev, "ip sleep failed!!!\n");
                ret = -EBUSY;
        } else {
                /* workaround: avoid wrong wakeup signal latch for some soc */
                usleep_range(100, 200);
        }

        return ret;
}

static int ssusb_phy_init(struct ssusb_mtk *ssusb)
{
        int i;
        int ret;

        for (i = 0; i < ssusb->num_phys; i++) {
                ret = phy_init(ssusb->phys[i]);
                if (ret)
                        goto exit_phy;
        }
        return 0;

exit_phy:
        for (; i > 0; i--)
                phy_exit(ssusb->phys[i - 1]);

        return ret;
}

static int ssusb_phy_exit(struct ssusb_mtk *ssusb)
{
        int i;

        for (i = 0; i < ssusb->num_phys; i++)
                phy_exit(ssusb->phys[i]);

        return 0;
}

static int ssusb_phy_power_on(struct ssusb_mtk *ssusb)
{
        int i;
        int ret;

        for (i = 0; i < ssusb->num_phys; i++) {
                ret = phy_power_on(ssusb->phys[i]);
                if (ret)
                        goto power_off_phy;
        }
        return 0;

power_off_phy:
        for (; i > 0; i--)
                phy_power_off(ssusb->phys[i - 1]);

        return ret;
}

static void ssusb_phy_power_off(struct ssusb_mtk *ssusb)
{
        unsigned int i;

        for (i = 0; i < ssusb->num_phys; i++)
                phy_power_off(ssusb->phys[i]);
}

static int ssusb_rscs_init(struct ssusb_mtk *ssusb)
{
        int ret = 0;

        ret = regulator_enable(ssusb->vusb33);
        if (ret) {
                dev_err(ssusb->dev, "failed to enable vusb33\n");
                goto vusb33_err;
        }

        ret = clk_bulk_prepare_enable(BULK_CLKS_CNT, ssusb->clks);
        if (ret)
                goto clks_err;

        ret = ssusb_phy_init(ssusb);
        if (ret) {
                dev_err(ssusb->dev, "failed to init phy\n");
                goto phy_init_err;
        }

        ret = ssusb_phy_power_on(ssusb);
        if (ret) {
                dev_err(ssusb->dev, "failed to power on phy\n");
                goto phy_err;
        }

        return 0;

phy_err:
        ssusb_phy_exit(ssusb);
phy_init_err:
        clk_bulk_disable_unprepare(BULK_CLKS_CNT, ssusb->clks);
clks_err:
        regulator_disable(ssusb->vusb33);
vusb33_err:
        return ret;
}

static void ssusb_rscs_exit(struct ssusb_mtk *ssusb)
{
        clk_bulk_disable_unprepare(BULK_CLKS_CNT, ssusb->clks);
        regulator_disable(ssusb->vusb33);
        ssusb_phy_power_off(ssusb);
        ssusb_phy_exit(ssusb);
}

static void ssusb_ip_sw_reset(struct ssusb_mtk *ssusb)
{
        /* reset whole ip (xhci & u3d) */
        mtu3_setbits(ssusb->ippc_base, U3D_SSUSB_IP_PW_CTRL0, SSUSB_IP_SW_RST);
        udelay(1);
        mtu3_clrbits(ssusb->ippc_base, U3D_SSUSB_IP_PW_CTRL0, SSUSB_IP_SW_RST);

        /*
         * device ip may be powered on in firmware/BROM stage before entering
         * kernel stage;
         * power down device ip, otherwise ip-sleep will fail when working as
         * host only mode
         */
        mtu3_setbits(ssusb->ippc_base, U3D_SSUSB_IP_PW_CTRL2, SSUSB_IP_DEV_PDN);
}

static void ssusb_u3_drd_check(struct ssusb_mtk *ssusb)
{
        struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;
        u32 dev_u3p_num;
        u32 host_u3p_num;
        u32 value;

        /* u3 port0 is disabled */
        if (ssusb->u3p_dis_msk & BIT(0)) {
                otg_sx->is_u3_drd = false;
                goto out;
        }

        value = mtu3_readl(ssusb->ippc_base, U3D_SSUSB_IP_DEV_CAP);
        dev_u3p_num = SSUSB_IP_DEV_U3_PORT_NUM(value);

        value = mtu3_readl(ssusb->ippc_base, U3D_SSUSB_IP_XHCI_CAP);
        host_u3p_num = SSUSB_IP_XHCI_U3_PORT_NUM(value);

        otg_sx->is_u3_drd = !!(dev_u3p_num && host_u3p_num);

out:
        dev_info(ssusb->dev, "usb3-drd: %d\n", otg_sx->is_u3_drd);
}

static int get_ssusb_rscs(struct platform_device *pdev, struct ssusb_mtk *ssusb)
{
        struct device_node *node = pdev->dev.of_node;
        struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;
        struct clk_bulk_data *clks = ssusb->clks;
        struct device *dev = &pdev->dev;
        int i;
        int ret;

        ssusb->vusb33 = devm_regulator_get(dev, "vusb33");
        if (IS_ERR(ssusb->vusb33)) {
                dev_err(dev, "failed to get vusb33\n");
                return PTR_ERR(ssusb->vusb33);
        }

        clks[0].id = "sys_ck";
        clks[1].id = "ref_ck";
        clks[2].id = "mcu_ck";
        clks[3].id = "dma_ck";
        clks[4].id = "xhci_ck";
        clks[5].id = "frmcnt_ck";
        ret = devm_clk_bulk_get_optional(dev, BULK_CLKS_CNT, clks);
        if (ret)
                return ret;

        ssusb->num_phys = of_count_phandle_with_args(node,
                        "phys", "#phy-cells");
        if (ssusb->num_phys > 0) {
                ssusb->phys = devm_kcalloc(dev, ssusb->num_phys,
                                        sizeof(*ssusb->phys), GFP_KERNEL);
                if (!ssusb->phys)
                        return -ENOMEM;
        } else {
                ssusb->num_phys = 0;
        }

        for (i = 0; i < ssusb->num_phys; i++) {
                ssusb->phys[i] = devm_of_phy_get_by_index(dev, node, i);
                if (IS_ERR(ssusb->phys[i])) {
                        dev_err(dev, "failed to get phy-%d\n", i);
                        return PTR_ERR(ssusb->phys[i]);
                }
        }

        ssusb->ippc_base = devm_platform_ioremap_resource_byname(pdev, "ippc");
        if (IS_ERR(ssusb->ippc_base))
                return PTR_ERR(ssusb->ippc_base);

        ssusb->wakeup_irq = platform_get_irq_byname_optional(pdev, "wakeup");
        if (ssusb->wakeup_irq == -EPROBE_DEFER)
                return ssusb->wakeup_irq;

        ssusb->dr_mode = usb_get_dr_mode(dev);
        if (ssusb->dr_mode == USB_DR_MODE_UNKNOWN)
                ssusb->dr_mode = USB_DR_MODE_OTG;

        of_property_read_u32(node, "mediatek,u3p-dis-msk", &ssusb->u3p_dis_msk);

        if (ssusb->dr_mode == USB_DR_MODE_PERIPHERAL)
                goto out;

        /* if host role is supported */
        ret = ssusb_wakeup_of_property_parse(ssusb, node);
        if (ret) {
                dev_err(dev, "failed to parse uwk property\n");
                return ret;
        }

        /* optional property, ignore the error if it does not exist */
        of_property_read_u32(node, "mediatek,u2p-dis-msk",
                             &ssusb->u2p_dis_msk);

        otg_sx->vbus = devm_regulator_get(dev, "vbus");
        if (IS_ERR(otg_sx->vbus)) {
                dev_err(dev, "failed to get vbus\n");
                return PTR_ERR(otg_sx->vbus);
        }

        if (ssusb->dr_mode == USB_DR_MODE_HOST)
                goto out;

        /* if dual-role mode is supported */
        otg_sx->manual_drd_enabled =
                of_property_read_bool(node, "enable-manual-drd");
        otg_sx->role_sw_used = of_property_read_bool(node, "usb-role-switch");

        /* can't disable port0 when use dual-role mode */
        ssusb->u2p_dis_msk &= ~0x1;

        if (otg_sx->role_sw_used || otg_sx->manual_drd_enabled)
                goto out;

        if (of_property_present(node, "extcon")) {
                otg_sx->edev = extcon_get_edev_by_phandle(ssusb->dev, 0);
                if (IS_ERR(otg_sx->edev)) {
                        return dev_err_probe(dev, PTR_ERR(otg_sx->edev),
                                             "couldn't get extcon device\n");
                }
        }

out:
        dev_info(dev, "dr_mode: %d, drd: %s\n", ssusb->dr_mode,
                 otg_sx->manual_drd_enabled ? "manual" : "auto");
        dev_info(dev, "u2p_dis_msk: %x, u3p_dis_msk: %x\n",
                 ssusb->u2p_dis_msk, ssusb->u3p_dis_msk);

        return 0;
}

static int mtu3_probe(struct platform_device *pdev)
{
        struct device_node *node = pdev->dev.of_node;
        struct device *dev = &pdev->dev;
        struct ssusb_mtk *ssusb;
        int ret = -ENOMEM;

        /* all elements are set to ZERO as default value */
        ssusb = devm_kzalloc(dev, sizeof(*ssusb), GFP_KERNEL);
        if (!ssusb)
                return -ENOMEM;

        ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
        if (ret) {
                dev_err(dev, "No suitable DMA config available\n");
                return -ENOTSUPP;
        }

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

        ret = get_ssusb_rscs(pdev, ssusb);
        if (ret)
                return ret;

        ssusb_debugfs_create_root(ssusb);

        /* enable power domain */
        pm_runtime_set_active(dev);
        pm_runtime_use_autosuspend(dev);
        pm_runtime_set_autosuspend_delay(dev, 4000);
        pm_runtime_enable(dev);
        pm_runtime_get_sync(dev);

        device_init_wakeup(dev, true);

        ret = ssusb_rscs_init(ssusb);
        if (ret)
                goto comm_init_err;

        if (ssusb->wakeup_irq > 0) {
                ret = dev_pm_set_dedicated_wake_irq_reverse(dev, ssusb->wakeup_irq);
                if (ret) {
                        dev_err(dev, "failed to set wakeup irq %d\n", ssusb->wakeup_irq);
                        goto comm_exit;
                }
                dev_info(dev, "wakeup irq %d\n", ssusb->wakeup_irq);
        }

        ret = device_reset_optional(dev);
        if (ret) {
                dev_err_probe(dev, ret, "failed to reset controller\n");
                goto comm_exit;
        }

        ssusb_ip_sw_reset(ssusb);
        ssusb_u3_drd_check(ssusb);

        if (IS_ENABLED(CONFIG_USB_MTU3_HOST))
                ssusb->dr_mode = USB_DR_MODE_HOST;
        else if (IS_ENABLED(CONFIG_USB_MTU3_GADGET))
                ssusb->dr_mode = USB_DR_MODE_PERIPHERAL;

        /* default as host */
        ssusb->is_host = !(ssusb->dr_mode == USB_DR_MODE_PERIPHERAL);

        switch (ssusb->dr_mode) {
        case USB_DR_MODE_PERIPHERAL:
                ret = ssusb_gadget_init(ssusb);
                if (ret) {
                        dev_err(dev, "failed to initialize gadget\n");
                        goto comm_exit;
                }
                break;
        case USB_DR_MODE_HOST:
                ret = ssusb_host_init(ssusb, node);
                if (ret) {
                        dev_err(dev, "failed to initialize host\n");
                        goto comm_exit;
                }
                break;
        case USB_DR_MODE_OTG:
                ret = ssusb_gadget_init(ssusb);
                if (ret) {
                        dev_err(dev, "failed to initialize gadget\n");
                        goto comm_exit;
                }

                ret = ssusb_host_init(ssusb, node);
                if (ret) {
                        dev_err(dev, "failed to initialize host\n");
                        goto gadget_exit;
                }

                ret = ssusb_otg_switch_init(ssusb);
                if (ret) {
                        dev_err(dev, "failed to initialize switch\n");
                        goto host_exit;
                }
                break;
        default:
                dev_err(dev, "unsupported mode: %d\n", ssusb->dr_mode);
                ret = -EINVAL;
                goto comm_exit;
        }

        device_enable_async_suspend(dev);
        pm_runtime_put_autosuspend(dev);
        pm_runtime_forbid(dev);

        return 0;

host_exit:
        ssusb_host_exit(ssusb);
gadget_exit:
        ssusb_gadget_exit(ssusb);
comm_exit:
        ssusb_rscs_exit(ssusb);
comm_init_err:
        pm_runtime_put_noidle(dev);
        pm_runtime_disable(dev);
        ssusb_debugfs_remove_root(ssusb);

        return ret;
}

static void mtu3_remove(struct platform_device *pdev)
{
        struct ssusb_mtk *ssusb = platform_get_drvdata(pdev);

        pm_runtime_get_sync(&pdev->dev);

        switch (ssusb->dr_mode) {
        case USB_DR_MODE_PERIPHERAL:
                ssusb_gadget_exit(ssusb);
                break;
        case USB_DR_MODE_HOST:
                ssusb_host_exit(ssusb);
                break;
        case USB_DR_MODE_OTG:
                ssusb_otg_switch_exit(ssusb);
                ssusb_gadget_exit(ssusb);
                ssusb_host_exit(ssusb);
                break;
        case USB_DR_MODE_UNKNOWN:
                /*
                 * This cannot happen because with dr_mode ==
                 * USB_DR_MODE_UNKNOWN, .probe() doesn't succeed and so
                 * .remove() wouldn't be called at all. However (little
                 * surprising) the compiler isn't smart enough to see that, so
                 * we explicitly have this case item to not make the compiler
                 * wail about an unhandled enumeration value.
                 */
                break;
        }

        ssusb_rscs_exit(ssusb);
        ssusb_debugfs_remove_root(ssusb);
        pm_runtime_disable(&pdev->dev);
        pm_runtime_put_noidle(&pdev->dev);
        pm_runtime_set_suspended(&pdev->dev);
}

static int resume_ip_and_ports(struct ssusb_mtk *ssusb, pm_message_t msg)
{
        switch (ssusb->dr_mode) {
        case USB_DR_MODE_PERIPHERAL:
                ssusb_gadget_resume(ssusb, msg);
                break;
        case USB_DR_MODE_HOST:
                ssusb_host_resume(ssusb, false);
                break;
        case USB_DR_MODE_OTG:
                ssusb_host_resume(ssusb, !ssusb->is_host);
                if (!ssusb->is_host)
                        ssusb_gadget_resume(ssusb, msg);

                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static int mtu3_suspend_common(struct device *dev, pm_message_t msg)
{
        struct ssusb_mtk *ssusb = dev_get_drvdata(dev);
        int ret = 0;

        dev_dbg(dev, "%s\n", __func__);

        switch (ssusb->dr_mode) {
        case USB_DR_MODE_PERIPHERAL:
                ret = ssusb_gadget_suspend(ssusb, msg);
                if (ret)
                        goto err;

                break;
        case USB_DR_MODE_HOST:
                ssusb_host_suspend(ssusb);
                break;
        case USB_DR_MODE_OTG:
                if (!ssusb->is_host) {
                        ret = ssusb_gadget_suspend(ssusb, msg);
                        if (ret)
                                goto err;
                }
                ssusb_host_suspend(ssusb);
                break;
        default:
                return -EINVAL;
        }

        ret = wait_for_ip_sleep(ssusb);
        if (ret)
                goto sleep_err;

        ssusb_phy_power_off(ssusb);
        clk_bulk_disable_unprepare(BULK_CLKS_CNT, ssusb->clks);
        ssusb_wakeup_set(ssusb, true);
        return 0;

sleep_err:
        resume_ip_and_ports(ssusb, msg);
err:
        return ret;
}

static int mtu3_resume_common(struct device *dev, pm_message_t msg)
{
        struct ssusb_mtk *ssusb = dev_get_drvdata(dev);
        int ret;

        dev_dbg(dev, "%s\n", __func__);

        ssusb_wakeup_set(ssusb, false);
        ret = clk_bulk_prepare_enable(BULK_CLKS_CNT, ssusb->clks);
        if (ret)
                goto clks_err;

        ret = ssusb_phy_power_on(ssusb);
        if (ret)
                goto phy_err;

        return resume_ip_and_ports(ssusb, msg);

phy_err:
        clk_bulk_disable_unprepare(BULK_CLKS_CNT, ssusb->clks);
clks_err:
        return ret;
}

static int __maybe_unused mtu3_suspend(struct device *dev)
{
        return mtu3_suspend_common(dev, PMSG_SUSPEND);
}

static int __maybe_unused mtu3_resume(struct device *dev)
{
        return mtu3_resume_common(dev, PMSG_SUSPEND);
}

static int __maybe_unused mtu3_runtime_suspend(struct device *dev)
{
        if (!device_may_wakeup(dev))
                return 0;

        return mtu3_suspend_common(dev, PMSG_AUTO_SUSPEND);
}

static int __maybe_unused mtu3_runtime_resume(struct device *dev)
{
        if (!device_may_wakeup(dev))
                return 0;

        return mtu3_resume_common(dev, PMSG_AUTO_SUSPEND);
}

static const struct dev_pm_ops mtu3_pm_ops = {
        SET_SYSTEM_SLEEP_PM_OPS(mtu3_suspend, mtu3_resume)
        SET_RUNTIME_PM_OPS(mtu3_runtime_suspend,
                           mtu3_runtime_resume, NULL)
};

#define DEV_PM_OPS (IS_ENABLED(CONFIG_PM) ? &mtu3_pm_ops : NULL)

static const struct of_device_id mtu3_of_match[] = {
        {.compatible = "mediatek,mt8173-mtu3",},
        {.compatible = "mediatek,mtu3",},
        {},
};
MODULE_DEVICE_TABLE(of, mtu3_of_match);

static struct platform_driver mtu3_driver = {
        .probe = mtu3_probe,
        .remove = mtu3_remove,
        .driver = {
                .name = MTU3_DRIVER_NAME,
                .pm = DEV_PM_OPS,
                .of_match_table = mtu3_of_match,
        },
};
module_platform_driver(mtu3_driver);

MODULE_AUTHOR("Chunfeng Yun <chunfeng.yun@mediatek.com>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("MediaTek USB3 DRD Controller Driver");