// SPDX-License-Identifier: GPL-2.0
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/usb/otg.h>
#include <linux/usb/usb_phy_generic.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/usb/of.h>

#include "phy-am335x-control.h"
#include "phy-generic.h"

struct am335x_phy {
        struct usb_phy_generic usb_phy_gen;
        struct phy_control *phy_ctrl;
        int id;
        enum usb_dr_mode dr_mode;
};

static int am335x_init(struct usb_phy *phy)
{
        struct am335x_phy *am_phy = dev_get_drvdata(phy->dev);

        phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true);
        return 0;
}

static void am335x_shutdown(struct usb_phy *phy)
{
        struct am335x_phy *am_phy = dev_get_drvdata(phy->dev);

        phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
}

static int am335x_phy_probe(struct platform_device *pdev)
{
        struct am335x_phy *am_phy;
        struct device *dev = &pdev->dev;
        int ret;

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

        am_phy->phy_ctrl = am335x_get_phy_control(dev);
        if (!am_phy->phy_ctrl)
                return -EPROBE_DEFER;

        am_phy->id = of_alias_get_id(pdev->dev.of_node, "phy");
        if (am_phy->id < 0) {
                dev_err(&pdev->dev, "Missing PHY id: %d\n", am_phy->id);
                return am_phy->id;
        }

        am_phy->dr_mode = of_usb_get_dr_mode_by_phy(pdev->dev.of_node, -1);

        ret = usb_phy_gen_create_phy(dev, &am_phy->usb_phy_gen);
        if (ret)
                return ret;

        am_phy->usb_phy_gen.phy.init = am335x_init;
        am_phy->usb_phy_gen.phy.shutdown = am335x_shutdown;

        platform_set_drvdata(pdev, am_phy);
        device_init_wakeup(dev, true);

        /*
         * If we leave PHY wakeup enabled then AM33XX wakes up
         * immediately from DS0. To avoid this we mark dev->power.can_wakeup
         * to false. The same is checked in suspend routine to decide
         * on whether to enable PHY wakeup or not.
         * PHY wakeup works fine in standby mode, there by allowing us to
         * handle remote wakeup, wakeup on disconnect and connect.
         */

        device_set_wakeup_enable(dev, false);
        phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);

        return usb_add_phy_dev(&am_phy->usb_phy_gen.phy);
}

static void am335x_phy_remove(struct platform_device *pdev)
{
        struct am335x_phy *am_phy = platform_get_drvdata(pdev);

        usb_remove_phy(&am_phy->usb_phy_gen.phy);
}

#ifdef CONFIG_PM_SLEEP
static int am335x_phy_suspend(struct device *dev)
{
        struct am335x_phy *am_phy = dev_get_drvdata(dev);

        /*
         * Enable phy wakeup only if dev->power.can_wakeup is true.
         * Make sure to enable wakeup to support remote wakeup  in
         * standby mode ( same is not supported in OFF(DS0) mode).
         * Enable it by doing
         * echo enabled > /sys/bus/platform/devices/<usb-phy-id>/power/wakeup
         */

        if (device_may_wakeup(dev))
                phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, true);

        phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);

        return 0;
}

static int am335x_phy_resume(struct device *dev)
{
        struct am335x_phy       *am_phy = dev_get_drvdata(dev);

        phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true);

        if (device_may_wakeup(dev))
                phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, false);

        return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(am335x_pm_ops, am335x_phy_suspend, am335x_phy_resume);

static const struct of_device_id am335x_phy_ids[] = {
        { .compatible = "ti,am335x-usb-phy" },
        { }
};
MODULE_DEVICE_TABLE(of, am335x_phy_ids);

static struct platform_driver am335x_phy_driver = {
        .probe          = am335x_phy_probe,
        .remove         = am335x_phy_remove,
        .driver         = {
                .name   = "am335x-phy-driver",
                .pm = &am335x_pm_ops,
                .of_match_table = am335x_phy_ids,
        },
};

module_platform_driver(am335x_phy_driver);
MODULE_DESCRIPTION("AM335x USB PHY Driver");
MODULE_LICENSE("GPL v2");