// SPDX-License-Identifier: GPL-2.0+
/*
 * Driver for the Renesas PHY uPD60620.
 *
 * Copyright (C) 2015 Softing Industrial Automation GmbH
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/phy.h>

#define UPD60620_PHY_ID    0xb8242824

/* Extended Registers and values */
/* PHY Special Control/Status    */
#define PHY_PHYSCR         0x1F      /* PHY.31 */
#define PHY_PHYSCR_10MB    0x0004    /* PHY speed = 10mb */
#define PHY_PHYSCR_100MB   0x0008    /* PHY speed = 100mb */
#define PHY_PHYSCR_DUPLEX  0x0010    /* PHY Duplex */

/* PHY Special Modes */
#define PHY_SPM            0x12      /* PHY.18 */

/* Init PHY */

static int upd60620_config_init(struct phy_device *phydev)
{
        /* Enable support for passive HUBs (could be a strap option) */
        /* PHYMODE: All speeds, HD in parallel detect */
        return phy_write(phydev, PHY_SPM, 0x0180 | phydev->mdio.addr);
}

/* Get PHY status from common registers */

static int upd60620_read_status(struct phy_device *phydev)
{
        int phy_state;

        /* Read negotiated state */
        phy_state = phy_read(phydev, MII_BMSR);
        if (phy_state < 0)
                return phy_state;

        phydev->link = 0;
        linkmode_zero(phydev->lp_advertising);
        phydev->pause = 0;
        phydev->asym_pause = 0;

        if (phy_state & (BMSR_ANEGCOMPLETE | BMSR_LSTATUS)) {
                phy_state = phy_read(phydev, PHY_PHYSCR);
                if (phy_state < 0)
                        return phy_state;

                if (phy_state & (PHY_PHYSCR_10MB | PHY_PHYSCR_100MB)) {
                        phydev->link = 1;
                        phydev->speed = SPEED_10;
                        phydev->duplex = DUPLEX_HALF;

                        if (phy_state & PHY_PHYSCR_100MB)
                                phydev->speed = SPEED_100;
                        if (phy_state & PHY_PHYSCR_DUPLEX)
                                phydev->duplex = DUPLEX_FULL;

                        phy_state = phy_read(phydev, MII_LPA);
                        if (phy_state < 0)
                                return phy_state;

                        mii_lpa_to_linkmode_lpa_t(phydev->lp_advertising,
                                                  phy_state);

                        phy_resolve_aneg_pause(phydev);
                }
        }
        return 0;
}

MODULE_DESCRIPTION("Renesas uPD60620 PHY driver");
MODULE_AUTHOR("Bernd Edlinger <bernd.edlinger@hotmail.de>");
MODULE_LICENSE("GPL");

static struct phy_driver upd60620_driver[1] = { {
        .phy_id         = UPD60620_PHY_ID,
        .phy_id_mask    = 0xfffffffe,
        .name           = "Renesas uPD60620",
        /* PHY_BASIC_FEATURES */
        .flags          = 0,
        .config_init    = upd60620_config_init,
        .read_status    = upd60620_read_status,
} };

module_phy_driver(upd60620_driver);

static const struct mdio_device_id __maybe_unused upd60620_tbl[] = {
        { UPD60620_PHY_ID, 0xfffffffe },
        { }
};

MODULE_DEVICE_TABLE(mdio, upd60620_tbl);