// SPDX-License-Identifier: GPL-2.0
/*
 * Driver for Teranetics PHY
 *
 * Author: Shaohui Xie <Shaohui.Xie@freescale.com>
 *
 * Copyright 2015 Freescale Semiconductor, Inc.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mii.h>
#include <linux/ethtool.h>
#include <linux/mdio.h>
#include <linux/phy.h>

MODULE_DESCRIPTION("Teranetics PHY driver");
MODULE_AUTHOR("Shaohui Xie <Shaohui.Xie@freescale.com>");
MODULE_LICENSE("GPL v2");

#define PHY_ID_TN2020   0x00a19410
#define MDIO_PHYXS_LNSTAT_SYNC0 0x0001
#define MDIO_PHYXS_LNSTAT_SYNC1 0x0002
#define MDIO_PHYXS_LNSTAT_SYNC2 0x0004
#define MDIO_PHYXS_LNSTAT_SYNC3 0x0008
#define MDIO_PHYXS_LNSTAT_ALIGN 0x1000

#define MDIO_PHYXS_LANE_READY   (MDIO_PHYXS_LNSTAT_SYNC0 | \
                                MDIO_PHYXS_LNSTAT_SYNC1 | \
                                MDIO_PHYXS_LNSTAT_SYNC2 | \
                                MDIO_PHYXS_LNSTAT_SYNC3 | \
                                MDIO_PHYXS_LNSTAT_ALIGN)

static int teranetics_aneg_done(struct phy_device *phydev)
{
        /* auto negotiation state can only be checked when using copper
         * port, if using fiber port, just lie it's done.
         */
        if (!phy_read_mmd(phydev, MDIO_MMD_VEND1, 93))
                return genphy_c45_aneg_done(phydev);

        return 1;
}

static int teranetics_read_status(struct phy_device *phydev)
{
        int reg;

        phydev->link = 1;

        phydev->speed = SPEED_10000;
        phydev->duplex = DUPLEX_FULL;

        if (!phy_read_mmd(phydev, MDIO_MMD_VEND1, 93)) {
                reg = phy_read_mmd(phydev, MDIO_MMD_PHYXS, MDIO_PHYXS_LNSTAT);
                if (reg < 0 ||
                    !((reg & MDIO_PHYXS_LANE_READY) == MDIO_PHYXS_LANE_READY)) {
                        phydev->link = 0;
                        return 0;
                }

                reg = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_STAT1);
                if (reg < 0 || !(reg & MDIO_STAT1_LSTATUS))
                        phydev->link = 0;
        }

        return 0;
}

static int teranetics_match_phy_device(struct phy_device *phydev,
                                       const struct phy_driver *phydrv)
{
        return phydev->c45_ids.device_ids[3] == PHY_ID_TN2020;
}

static struct phy_driver teranetics_driver[] = {
{
        .phy_id         = PHY_ID_TN2020,
        .phy_id_mask    = 0xffffffff,
        .name           = "Teranetics TN2020",
        .features       = PHY_10GBIT_FEATURES,
        .aneg_done      = teranetics_aneg_done,
        .config_aneg    = gen10g_config_aneg,
        .read_status    = teranetics_read_status,
        .match_phy_device = teranetics_match_phy_device,
},
};

module_phy_driver(teranetics_driver);

static const struct mdio_device_id __maybe_unused teranetics_tbl[] = {
        { PHY_ID_TN2020, 0xffffffff },
        { }
};

MODULE_DEVICE_TABLE(mdio, teranetics_tbl);