root/drivers/phy/samsung/phy-samsung-usb2.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Samsung SoC USB 1.1/2.0 PHY driver
 *
 * Copyright (C) 2013 Samsung Electronics Co., Ltd.
 * Author: Kamil Debski <k.debski@samsung.com>
 */

#include <linux/clk.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include "phy-samsung-usb2.h"

static int samsung_usb2_phy_power_on(struct phy *phy)
{
        struct samsung_usb2_phy_instance *inst = phy_get_drvdata(phy);
        struct samsung_usb2_phy_driver *drv = inst->drv;
        int ret;

        dev_dbg(drv->dev, "Request to power_on \"%s\" usb phy\n",
                inst->cfg->label);

        if (drv->vbus) {
                ret = regulator_enable(drv->vbus);
                if (ret)
                        goto err_regulator;
        }

        ret = clk_prepare_enable(drv->clk);
        if (ret)
                goto err_main_clk;
        ret = clk_prepare_enable(drv->ref_clk);
        if (ret)
                goto err_instance_clk;
        if (inst->cfg->power_on) {
                spin_lock(&drv->lock);
                ret = inst->cfg->power_on(inst);
                spin_unlock(&drv->lock);
                if (ret)
                        goto err_power_on;
        }

        return 0;

err_power_on:
        clk_disable_unprepare(drv->ref_clk);
err_instance_clk:
        clk_disable_unprepare(drv->clk);
err_main_clk:
        if (drv->vbus)
                regulator_disable(drv->vbus);
err_regulator:
        return ret;
}

static int samsung_usb2_phy_power_off(struct phy *phy)
{
        struct samsung_usb2_phy_instance *inst = phy_get_drvdata(phy);
        struct samsung_usb2_phy_driver *drv = inst->drv;
        int ret = 0;

        dev_dbg(drv->dev, "Request to power_off \"%s\" usb phy\n",
                inst->cfg->label);
        if (inst->cfg->power_off) {
                spin_lock(&drv->lock);
                ret = inst->cfg->power_off(inst);
                spin_unlock(&drv->lock);
                if (ret)
                        return ret;
        }
        clk_disable_unprepare(drv->ref_clk);
        clk_disable_unprepare(drv->clk);
        if (drv->vbus)
                ret = regulator_disable(drv->vbus);

        return ret;
}

static const struct phy_ops samsung_usb2_phy_ops = {
        .power_on       = samsung_usb2_phy_power_on,
        .power_off      = samsung_usb2_phy_power_off,
        .owner          = THIS_MODULE,
};

static struct phy *samsung_usb2_phy_xlate(struct device *dev,
                                        const struct of_phandle_args *args)
{
        struct samsung_usb2_phy_driver *drv;

        drv = dev_get_drvdata(dev);
        if (!drv)
                return ERR_PTR(-EINVAL);

        if (WARN_ON(args->args[0] >= drv->cfg->num_phys))
                return ERR_PTR(-ENODEV);

        return drv->instances[args->args[0]].phy;
}

static const struct of_device_id samsung_usb2_phy_of_match[] = {
#ifdef CONFIG_PHY_EXYNOS4X12_USB2
        {
                .compatible = "samsung,exynos3250-usb2-phy",
                .data = &exynos3250_usb2_phy_config,
        },
#endif
#ifdef CONFIG_PHY_EXYNOS4210_USB2
        {
                .compatible = "samsung,exynos4210-usb2-phy",
                .data = &exynos4210_usb2_phy_config,
        },
#endif
#ifdef CONFIG_PHY_EXYNOS4X12_USB2
        {
                .compatible = "samsung,exynos4x12-usb2-phy",
                .data = &exynos4x12_usb2_phy_config,
        },
#endif
#ifdef CONFIG_PHY_EXYNOS5250_USB2
        {
                .compatible = "samsung,exynos5250-usb2-phy",
                .data = &exynos5250_usb2_phy_config,
        },
        {
                .compatible = "samsung,exynos5420-usb2-phy",
                .data = &exynos5420_usb2_phy_config,
        },
#endif
#ifdef CONFIG_PHY_S5PV210_USB2
        {
                .compatible = "samsung,s5pv210-usb2-phy",
                .data = &s5pv210_usb2_phy_config,
        },
#endif
        { },
};
MODULE_DEVICE_TABLE(of, samsung_usb2_phy_of_match);

static int samsung_usb2_phy_probe(struct platform_device *pdev)
{
        const struct samsung_usb2_phy_config *cfg;
        struct device *dev = &pdev->dev;
        struct phy_provider *phy_provider;
        struct samsung_usb2_phy_driver *drv;
        int i, ret;

        if (!pdev->dev.of_node) {
                dev_err(dev, "This driver is required to be instantiated from device tree\n");
                return -EINVAL;
        }

        cfg = of_device_get_match_data(dev);
        if (!cfg)
                return -EINVAL;

        drv = devm_kzalloc(dev, struct_size(drv, instances, cfg->num_phys),
                           GFP_KERNEL);
        if (!drv)
                return -ENOMEM;

        dev_set_drvdata(dev, drv);
        spin_lock_init(&drv->lock);

        drv->cfg = cfg;
        drv->dev = dev;

        drv->reg_phy = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(drv->reg_phy)) {
                dev_err(dev, "Failed to map register memory (phy)\n");
                return PTR_ERR(drv->reg_phy);
        }

        drv->reg_pmu = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
                "samsung,pmureg-phandle");
        if (IS_ERR(drv->reg_pmu)) {
                dev_err(dev, "Failed to map PMU registers (via syscon)\n");
                return PTR_ERR(drv->reg_pmu);
        }

        if (drv->cfg->has_mode_switch) {
                drv->reg_sys = syscon_regmap_lookup_by_phandle(
                                pdev->dev.of_node, "samsung,sysreg-phandle");
                if (IS_ERR(drv->reg_sys)) {
                        dev_err(dev, "Failed to map system registers (via syscon)\n");
                        return PTR_ERR(drv->reg_sys);
                }
        }

        drv->clk = devm_clk_get(dev, "phy");
        if (IS_ERR(drv->clk)) {
                dev_err(dev, "Failed to get clock of phy controller\n");
                return PTR_ERR(drv->clk);
        }

        drv->ref_clk = devm_clk_get(dev, "ref");
        if (IS_ERR(drv->ref_clk)) {
                dev_err(dev, "Failed to get reference clock for the phy controller\n");
                return PTR_ERR(drv->ref_clk);
        }

        drv->ref_rate = clk_get_rate(drv->ref_clk);
        if (drv->cfg->rate_to_clk) {
                ret = drv->cfg->rate_to_clk(drv->ref_rate, &drv->ref_reg_val);
                if (ret)
                        return ret;
        }

        drv->vbus = devm_regulator_get(dev, "vbus");
        if (IS_ERR(drv->vbus)) {
                ret = PTR_ERR(drv->vbus);
                if (ret == -EPROBE_DEFER)
                        return ret;
                drv->vbus = NULL;
        }

        for (i = 0; i < drv->cfg->num_phys; i++) {
                char *label = drv->cfg->phys[i].label;
                struct samsung_usb2_phy_instance *p = &drv->instances[i];

                dev_dbg(dev, "Creating phy \"%s\"\n", label);
                p->phy = devm_phy_create(dev, NULL, &samsung_usb2_phy_ops);
                if (IS_ERR(p->phy)) {
                        dev_err(drv->dev, "Failed to create usb2_phy \"%s\"\n",
                                label);
                        return PTR_ERR(p->phy);
                }

                p->cfg = &drv->cfg->phys[i];
                p->drv = drv;
                phy_set_bus_width(p->phy, 8);
                phy_set_drvdata(p->phy, p);
        }

        phy_provider = devm_of_phy_provider_register(dev,
                                                        samsung_usb2_phy_xlate);
        if (IS_ERR(phy_provider)) {
                dev_err(drv->dev, "Failed to register phy provider\n");
                return PTR_ERR(phy_provider);
        }

        return 0;
}

static struct platform_driver samsung_usb2_phy_driver = {
        .probe  = samsung_usb2_phy_probe,
        .driver = {
                .of_match_table = samsung_usb2_phy_of_match,
                .name           = "samsung-usb2-phy",
                .suppress_bind_attrs = true,
        }
};

module_platform_driver(samsung_usb2_phy_driver);
MODULE_DESCRIPTION("Samsung S5P/Exynos SoC USB PHY driver");
MODULE_AUTHOR("Kamil Debski <k.debski@samsung.com>");
MODULE_LICENSE("GPL v2");