// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2016 Linaro Ltd
 */
#include <linux/module.h>
#include <linux/ulpi/driver.h>
#include <linux/ulpi/regs.h>
#include <linux/phy/phy.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pinctrl/pinctrl-state.h>
#include <linux/delay.h>
#include <linux/clk.h>

#define ULPI_HSIC_CFG           0x30
#define ULPI_HSIC_IO_CAL        0x33

struct qcom_usb_hsic_phy {
        struct ulpi *ulpi;
        struct phy *phy;
        struct pinctrl *pctl;
        struct clk *phy_clk;
        struct clk *cal_clk;
        struct clk *cal_sleep_clk;
};

static int qcom_usb_hsic_phy_power_on(struct phy *phy)
{
        struct qcom_usb_hsic_phy *uphy = phy_get_drvdata(phy);
        struct ulpi *ulpi = uphy->ulpi;
        struct pinctrl_state *pins_default;
        int ret;

        ret = clk_prepare_enable(uphy->phy_clk);
        if (ret)
                return ret;

        ret = clk_prepare_enable(uphy->cal_clk);
        if (ret)
                goto err_cal;

        ret = clk_prepare_enable(uphy->cal_sleep_clk);
        if (ret)
                goto err_sleep;

        /* Set periodic calibration interval to ~2.048sec in HSIC_IO_CAL_REG */
        ret = ulpi_write(ulpi, ULPI_HSIC_IO_CAL, 0xff);
        if (ret)
                goto err_ulpi;

        /* Enable periodic IO calibration in HSIC_CFG register */
        ret = ulpi_write(ulpi, ULPI_HSIC_CFG, 0xa8);
        if (ret)
                goto err_ulpi;

        /* Configure pins for HSIC functionality */
        pins_default = pinctrl_lookup_state(uphy->pctl, PINCTRL_STATE_DEFAULT);
        if (IS_ERR(pins_default)) {
                ret = PTR_ERR(pins_default);
                goto err_ulpi;
        }

        ret = pinctrl_select_state(uphy->pctl, pins_default);
        if (ret)
                goto err_ulpi;

         /* Enable HSIC mode in HSIC_CFG register */
        ret = ulpi_write(ulpi, ULPI_SET(ULPI_HSIC_CFG), 0x01);
        if (ret)
                goto err_ulpi;

        /* Disable auto-resume */
        ret = ulpi_write(ulpi, ULPI_CLR(ULPI_IFC_CTRL),
                         ULPI_IFC_CTRL_AUTORESUME);
        if (ret)
                goto err_ulpi;

        return ret;
err_ulpi:
        clk_disable_unprepare(uphy->cal_sleep_clk);
err_sleep:
        clk_disable_unprepare(uphy->cal_clk);
err_cal:
        clk_disable_unprepare(uphy->phy_clk);
        return ret;
}

static int qcom_usb_hsic_phy_power_off(struct phy *phy)
{
        struct qcom_usb_hsic_phy *uphy = phy_get_drvdata(phy);

        clk_disable_unprepare(uphy->cal_sleep_clk);
        clk_disable_unprepare(uphy->cal_clk);
        clk_disable_unprepare(uphy->phy_clk);

        return 0;
}

static const struct phy_ops qcom_usb_hsic_phy_ops = {
        .power_on = qcom_usb_hsic_phy_power_on,
        .power_off = qcom_usb_hsic_phy_power_off,
        .owner = THIS_MODULE,
};

static int qcom_usb_hsic_phy_probe(struct ulpi *ulpi)
{
        struct qcom_usb_hsic_phy *uphy;
        struct phy_provider *p;
        struct clk *clk;

        uphy = devm_kzalloc(&ulpi->dev, sizeof(*uphy), GFP_KERNEL);
        if (!uphy)
                return -ENOMEM;
        ulpi_set_drvdata(ulpi, uphy);

        uphy->ulpi = ulpi;
        uphy->pctl = devm_pinctrl_get(&ulpi->dev);
        if (IS_ERR(uphy->pctl))
                return PTR_ERR(uphy->pctl);

        uphy->phy_clk = clk = devm_clk_get(&ulpi->dev, "phy");
        if (IS_ERR(clk))
                return PTR_ERR(clk);

        uphy->cal_clk = clk = devm_clk_get(&ulpi->dev, "cal");
        if (IS_ERR(clk))
                return PTR_ERR(clk);

        uphy->cal_sleep_clk = clk = devm_clk_get(&ulpi->dev, "cal_sleep");
        if (IS_ERR(clk))
                return PTR_ERR(clk);

        uphy->phy = devm_phy_create(&ulpi->dev, ulpi->dev.of_node,
                                    &qcom_usb_hsic_phy_ops);
        if (IS_ERR(uphy->phy))
                return PTR_ERR(uphy->phy);
        phy_set_drvdata(uphy->phy, uphy);

        p = devm_of_phy_provider_register(&ulpi->dev, of_phy_simple_xlate);
        return PTR_ERR_OR_ZERO(p);
}

static const struct of_device_id qcom_usb_hsic_phy_match[] = {
        { .compatible = "qcom,usb-hsic-phy", },
        { }
};
MODULE_DEVICE_TABLE(of, qcom_usb_hsic_phy_match);

static struct ulpi_driver qcom_usb_hsic_phy_driver = {
        .probe = qcom_usb_hsic_phy_probe,
        .driver = {
                .name = "qcom_usb_hsic_phy",
                .of_match_table = qcom_usb_hsic_phy_match,
        },
};
module_ulpi_driver(qcom_usb_hsic_phy_driver);

MODULE_DESCRIPTION("Qualcomm USB HSIC phy");
MODULE_LICENSE("GPL v2");