// SPDX-License-Identifier: GPL-2.0
/*
 * phylink models the MAC to optional PHY connection, supporting
 * technologies such as SFP cages where the PHY is hot-pluggable.
 *
 * Copyright (C) 2015 Russell King
 */
#include <linux/acpi.h>
#include <linux/ethtool.h>
#include <linux/export.h>
#include <linux/gpio/consumer.h>
#include <linux/netdevice.h>
#include <linux/of.h>
#include <linux/of_mdio.h>
#include <linux/phy.h>
#include <linux/phy_fixed.h>
#include <linux/phylink.h>
#include <linux/rtnetlink.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <linux/workqueue.h>

#include "sfp.h"
#include "swphy.h"

#define SUPPORTED_INTERFACES \
        (SUPPORTED_TP | SUPPORTED_MII | SUPPORTED_FIBRE | \
         SUPPORTED_BNC | SUPPORTED_AUI | SUPPORTED_Backplane)
#define ADVERTISED_INTERFACES \
        (ADVERTISED_TP | ADVERTISED_MII | ADVERTISED_FIBRE | \
         ADVERTISED_BNC | ADVERTISED_AUI | ADVERTISED_Backplane)

enum {
        PHYLINK_DISABLE_STOPPED,
        PHYLINK_DISABLE_LINK,
        PHYLINK_DISABLE_MAC_WOL,
};

/**
 * struct phylink - internal data type for phylink
 */
struct phylink {
        /* private: */
        struct net_device *netdev;
        const struct phylink_mac_ops *mac_ops;
        const struct phylink_pcs_ops *pcs_ops;
        struct phylink_config *config;
        struct phylink_pcs *pcs;
        struct device *dev;
        unsigned int old_link_state:1;

        unsigned long phylink_disable_state; /* bitmask of disables */
        struct phy_device *phydev;
        phy_interface_t link_interface; /* PHY_INTERFACE_xxx */
        u8 cfg_link_an_mode;            /* MLO_AN_xxx */
        u8 cur_link_an_mode;
        u8 link_port;                   /* The current non-phy ethtool port */
        __ETHTOOL_DECLARE_LINK_MODE_MASK(supported);

        /* The link configuration settings */
        struct phylink_link_state link_config;

        /* The current settings */
        phy_interface_t cur_interface;

        struct gpio_desc *link_gpio;
        unsigned int link_irq;
        struct timer_list link_poll;
        void (*get_fixed_state)(struct net_device *dev,
                                struct phylink_link_state *s);

        struct mutex state_mutex;
        struct phylink_link_state phy_state;
        struct work_struct resolve;

        bool mac_link_dropped;

        struct sfp_bus *sfp_bus;
        bool sfp_may_have_phy;
        __ETHTOOL_DECLARE_LINK_MODE_MASK(sfp_support);
        u8 sfp_port;
};

#define phylink_printk(level, pl, fmt, ...) \
        do { \
                if ((pl)->config->type == PHYLINK_NETDEV) \
                        netdev_printk(level, (pl)->netdev, fmt, ##__VA_ARGS__); \
                else if ((pl)->config->type == PHYLINK_DEV) \
                        dev_printk(level, (pl)->dev, fmt, ##__VA_ARGS__); \
        } while (0)

#define phylink_err(pl, fmt, ...) \
        phylink_printk(KERN_ERR, pl, fmt, ##__VA_ARGS__)
#define phylink_warn(pl, fmt, ...) \
        phylink_printk(KERN_WARNING, pl, fmt, ##__VA_ARGS__)
#define phylink_info(pl, fmt, ...) \
        phylink_printk(KERN_INFO, pl, fmt, ##__VA_ARGS__)
#if defined(CONFIG_DYNAMIC_DEBUG)
#define phylink_dbg(pl, fmt, ...) \
do {                                                                    \
        if ((pl)->config->type == PHYLINK_NETDEV)                       \
                netdev_dbg((pl)->netdev, fmt, ##__VA_ARGS__);           \
        else if ((pl)->config->type == PHYLINK_DEV)                     \
                dev_dbg((pl)->dev, fmt, ##__VA_ARGS__);                 \
} while (0)
#elif defined(DEBUG)
#define phylink_dbg(pl, fmt, ...)                                       \
        phylink_printk(KERN_DEBUG, pl, fmt, ##__VA_ARGS__)
#else
#define phylink_dbg(pl, fmt, ...)                                       \
({                                                                      \
        if (0)                                                          \
                phylink_printk(KERN_DEBUG, pl, fmt, ##__VA_ARGS__);     \
})
#endif

/**
 * phylink_set_port_modes() - set the port type modes in the ethtool mask
 * @mask: ethtool link mode mask
 *
 * Sets all the port type modes in the ethtool mask.  MAC drivers should
 * use this in their 'validate' callback.
 */
void phylink_set_port_modes(unsigned long *mask)
{
        phylink_set(mask, TP);
        phylink_set(mask, AUI);
        phylink_set(mask, MII);
        phylink_set(mask, FIBRE);
        phylink_set(mask, BNC);
        phylink_set(mask, Backplane);
}
EXPORT_SYMBOL_GPL(phylink_set_port_modes);

static int phylink_is_empty_linkmode(const unsigned long *linkmode)
{
        __ETHTOOL_DECLARE_LINK_MODE_MASK(tmp) = { 0, };

        phylink_set_port_modes(tmp);
        phylink_set(tmp, Autoneg);
        phylink_set(tmp, Pause);
        phylink_set(tmp, Asym_Pause);

        return linkmode_subset(linkmode, tmp);
}

static const char *phylink_an_mode_str(unsigned int mode)
{
        static const char *modestr[] = {
                [MLO_AN_PHY] = "phy",
                [MLO_AN_FIXED] = "fixed",
                [MLO_AN_INBAND] = "inband",
        };

        return mode < ARRAY_SIZE(modestr) ? modestr[mode] : "unknown";
}

static int phylink_validate(struct phylink *pl, unsigned long *supported,
                            struct phylink_link_state *state)
{
        pl->mac_ops->validate(pl->config, supported, state);

        return phylink_is_empty_linkmode(supported) ? -EINVAL : 0;
}

static int phylink_parse_fixedlink(struct phylink *pl,
                                   struct fwnode_handle *fwnode)
{
        struct fwnode_handle *fixed_node;
        const struct phy_setting *s;
        struct gpio_desc *desc;
        u32 speed;
        int ret;

        fixed_node = fwnode_get_named_child_node(fwnode, "fixed-link");
        if (fixed_node) {
                ret = fwnode_property_read_u32(fixed_node, "speed", &speed);

                pl->link_config.speed = speed;
                pl->link_config.duplex = DUPLEX_HALF;

                if (fwnode_property_read_bool(fixed_node, "full-duplex"))
                        pl->link_config.duplex = DUPLEX_FULL;

                /* We treat the "pause" and "asym-pause" terminology as
                 * defining the link partner's ability.
                 */
                if (fwnode_property_read_bool(fixed_node, "pause"))
                        __set_bit(ETHTOOL_LINK_MODE_Pause_BIT,
                                  pl->link_config.lp_advertising);
                if (fwnode_property_read_bool(fixed_node, "asym-pause"))
                        __set_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
                                  pl->link_config.lp_advertising);

                if (ret == 0) {
                        desc = fwnode_gpiod_get_index(fixed_node, "link", 0,
                                                      GPIOD_IN, "?");

                        if (!IS_ERR(desc))
                                pl->link_gpio = desc;
                        else if (desc == ERR_PTR(-EPROBE_DEFER))
                                ret = -EPROBE_DEFER;
                }
                fwnode_handle_put(fixed_node);

                if (ret)
                        return ret;
        } else {
                u32 prop[5];

                ret = fwnode_property_read_u32_array(fwnode, "fixed-link",
                                                     NULL, 0);
                if (ret != ARRAY_SIZE(prop)) {
                        phylink_err(pl, "broken fixed-link?\n");
                        return -EINVAL;
                }

                ret = fwnode_property_read_u32_array(fwnode, "fixed-link",
                                                     prop, ARRAY_SIZE(prop));
                if (!ret) {
                        pl->link_config.duplex = prop[1] ?
                                                DUPLEX_FULL : DUPLEX_HALF;
                        pl->link_config.speed = prop[2];
                        if (prop[3])
                                __set_bit(ETHTOOL_LINK_MODE_Pause_BIT,
                                          pl->link_config.lp_advertising);
                        if (prop[4])
                                __set_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
                                          pl->link_config.lp_advertising);
                }
        }

        if (pl->link_config.speed > SPEED_1000 &&
            pl->link_config.duplex != DUPLEX_FULL)
                phylink_warn(pl, "fixed link specifies half duplex for %dMbps link?\n",
                             pl->link_config.speed);

        bitmap_fill(pl->supported, __ETHTOOL_LINK_MODE_MASK_NBITS);
        linkmode_copy(pl->link_config.advertising, pl->supported);
        phylink_validate(pl, pl->supported, &pl->link_config);

        s = phy_lookup_setting(pl->link_config.speed, pl->link_config.duplex,
                               pl->supported, true);
        linkmode_zero(pl->supported);
        phylink_set(pl->supported, MII);
        phylink_set(pl->supported, Pause);
        phylink_set(pl->supported, Asym_Pause);
        phylink_set(pl->supported, Autoneg);
        if (s) {
                __set_bit(s->bit, pl->supported);
                __set_bit(s->bit, pl->link_config.lp_advertising);
        } else {
                phylink_warn(pl, "fixed link %s duplex %dMbps not recognised\n",
                             pl->link_config.duplex == DUPLEX_FULL ? "full" : "half",
                             pl->link_config.speed);
        }

        linkmode_and(pl->link_config.advertising, pl->link_config.advertising,
                     pl->supported);

        pl->link_config.link = 1;
        pl->link_config.an_complete = 1;

        return 0;
}

static int phylink_parse_mode(struct phylink *pl, struct fwnode_handle *fwnode)
{
        struct fwnode_handle *dn;
        const char *managed;

        dn = fwnode_get_named_child_node(fwnode, "fixed-link");
        if (dn || fwnode_property_present(fwnode, "fixed-link"))
                pl->cfg_link_an_mode = MLO_AN_FIXED;
        fwnode_handle_put(dn);

        if ((fwnode_property_read_string(fwnode, "managed", &managed) == 0 &&
             strcmp(managed, "in-band-status") == 0) ||
            pl->config->ovr_an_inband) {
                if (pl->cfg_link_an_mode == MLO_AN_FIXED) {
                        phylink_err(pl,
                                    "can't use both fixed-link and in-band-status\n");
                        return -EINVAL;
                }

                linkmode_zero(pl->supported);
                phylink_set(pl->supported, MII);
                phylink_set(pl->supported, Autoneg);
                phylink_set(pl->supported, Asym_Pause);
                phylink_set(pl->supported, Pause);
                pl->link_config.an_enabled = true;
                pl->cfg_link_an_mode = MLO_AN_INBAND;

                switch (pl->link_config.interface) {
                case PHY_INTERFACE_MODE_SGMII:
                case PHY_INTERFACE_MODE_QSGMII:
                        phylink_set(pl->supported, 10baseT_Half);
                        phylink_set(pl->supported, 10baseT_Full);
                        phylink_set(pl->supported, 100baseT_Half);
                        phylink_set(pl->supported, 100baseT_Full);
                        phylink_set(pl->supported, 1000baseT_Half);
                        phylink_set(pl->supported, 1000baseT_Full);
                        break;

                case PHY_INTERFACE_MODE_1000BASEX:
                        phylink_set(pl->supported, 1000baseX_Full);
                        break;

                case PHY_INTERFACE_MODE_2500BASEX:
                        phylink_set(pl->supported, 2500baseX_Full);
                        break;

                case PHY_INTERFACE_MODE_5GBASER:
                        phylink_set(pl->supported, 5000baseT_Full);
                        break;

                case PHY_INTERFACE_MODE_25GBASER:
                        phylink_set(pl->supported, 25000baseCR_Full);
                        phylink_set(pl->supported, 25000baseKR_Full);
                        phylink_set(pl->supported, 25000baseSR_Full);
                        fallthrough;
                case PHY_INTERFACE_MODE_USXGMII:
                case PHY_INTERFACE_MODE_10GKR:
                case PHY_INTERFACE_MODE_10GBASER:
                        phylink_set(pl->supported, 10baseT_Half);
                        phylink_set(pl->supported, 10baseT_Full);
                        phylink_set(pl->supported, 100baseT_Half);
                        phylink_set(pl->supported, 100baseT_Full);
                        phylink_set(pl->supported, 1000baseT_Half);
                        phylink_set(pl->supported, 1000baseT_Full);
                        phylink_set(pl->supported, 1000baseX_Full);
                        phylink_set(pl->supported, 1000baseKX_Full);
                        phylink_set(pl->supported, 2500baseT_Full);
                        phylink_set(pl->supported, 2500baseX_Full);
                        phylink_set(pl->supported, 5000baseT_Full);
                        phylink_set(pl->supported, 10000baseT_Full);
                        phylink_set(pl->supported, 10000baseKR_Full);
                        phylink_set(pl->supported, 10000baseKX4_Full);
                        phylink_set(pl->supported, 10000baseCR_Full);
                        phylink_set(pl->supported, 10000baseSR_Full);
                        phylink_set(pl->supported, 10000baseLR_Full);
                        phylink_set(pl->supported, 10000baseLRM_Full);
                        phylink_set(pl->supported, 10000baseER_Full);
                        break;

                case PHY_INTERFACE_MODE_XLGMII:
                        phylink_set(pl->supported, 25000baseCR_Full);
                        phylink_set(pl->supported, 25000baseKR_Full);
                        phylink_set(pl->supported, 25000baseSR_Full);
                        phylink_set(pl->supported, 40000baseKR4_Full);
                        phylink_set(pl->supported, 40000baseCR4_Full);
                        phylink_set(pl->supported, 40000baseSR4_Full);
                        phylink_set(pl->supported, 40000baseLR4_Full);
                        phylink_set(pl->supported, 50000baseCR2_Full);
                        phylink_set(pl->supported, 50000baseKR2_Full);
                        phylink_set(pl->supported, 50000baseSR2_Full);
                        phylink_set(pl->supported, 50000baseKR_Full);
                        phylink_set(pl->supported, 50000baseSR_Full);
                        phylink_set(pl->supported, 50000baseCR_Full);
                        phylink_set(pl->supported, 50000baseLR_ER_FR_Full);
                        phylink_set(pl->supported, 50000baseDR_Full);
                        phylink_set(pl->supported, 100000baseKR4_Full);
                        phylink_set(pl->supported, 100000baseSR4_Full);
                        phylink_set(pl->supported, 100000baseCR4_Full);
                        phylink_set(pl->supported, 100000baseLR4_ER4_Full);
                        phylink_set(pl->supported, 100000baseKR2_Full);
                        phylink_set(pl->supported, 100000baseSR2_Full);
                        phylink_set(pl->supported, 100000baseCR2_Full);
                        phylink_set(pl->supported, 100000baseLR2_ER2_FR2_Full);
                        phylink_set(pl->supported, 100000baseDR2_Full);
                        break;

                default:
                        phylink_err(pl,
                                    "incorrect link mode %s for in-band status\n",
                                    phy_modes(pl->link_config.interface));
                        return -EINVAL;
                }

                linkmode_copy(pl->link_config.advertising, pl->supported);

                if (phylink_validate(pl, pl->supported, &pl->link_config)) {
                        phylink_err(pl,
                                    "failed to validate link configuration for in-band status\n");
                        return -EINVAL;
                }

                /* Check if MAC/PCS also supports Autoneg. */
                pl->link_config.an_enabled = phylink_test(pl->supported, Autoneg);
        }

        return 0;
}

static void phylink_apply_manual_flow(struct phylink *pl,
                                      struct phylink_link_state *state)
{
        /* If autoneg is disabled, pause AN is also disabled */
        if (!state->an_enabled)
                state->pause &= ~MLO_PAUSE_AN;

        /* Manual configuration of pause modes */
        if (!(pl->link_config.pause & MLO_PAUSE_AN))
                state->pause = pl->link_config.pause;
}

static void phylink_resolve_flow(struct phylink_link_state *state)
{
        bool tx_pause, rx_pause;

        state->pause = MLO_PAUSE_NONE;
        if (state->duplex == DUPLEX_FULL) {
                linkmode_resolve_pause(state->advertising,
                                       state->lp_advertising,
                                       &tx_pause, &rx_pause);
                if (tx_pause)
                        state->pause |= MLO_PAUSE_TX;
                if (rx_pause)
                        state->pause |= MLO_PAUSE_RX;
        }
}

static void phylink_mac_config(struct phylink *pl,
                               const struct phylink_link_state *state)
{
        phylink_dbg(pl,
                    "%s: mode=%s/%s/%s/%s adv=%*pb pause=%02x link=%u an=%u\n",
                    __func__, phylink_an_mode_str(pl->cur_link_an_mode),
                    phy_modes(state->interface),
                    phy_speed_to_str(state->speed),
                    phy_duplex_to_str(state->duplex),
                    __ETHTOOL_LINK_MODE_MASK_NBITS, state->advertising,
                    state->pause, state->link, state->an_enabled);

        pl->mac_ops->mac_config(pl->config, pl->cur_link_an_mode, state);
}

static void phylink_mac_pcs_an_restart(struct phylink *pl)
{
        if (pl->link_config.an_enabled &&
            phy_interface_mode_is_8023z(pl->link_config.interface) &&
            phylink_autoneg_inband(pl->cur_link_an_mode)) {
                if (pl->pcs_ops)
                        pl->pcs_ops->pcs_an_restart(pl->pcs);
                else
                        pl->mac_ops->mac_an_restart(pl->config);
        }
}

static void phylink_major_config(struct phylink *pl, bool restart,
                                  const struct phylink_link_state *state)
{
        int err;

        phylink_dbg(pl, "major config %s\n", phy_modes(state->interface));

        if (pl->mac_ops->mac_prepare) {
                err = pl->mac_ops->mac_prepare(pl->config, pl->cur_link_an_mode,
                                               state->interface);
                if (err < 0) {
                        phylink_err(pl, "mac_prepare failed: %pe\n",
                                    ERR_PTR(err));
                        return;
                }
        }

        phylink_mac_config(pl, state);

        if (pl->pcs_ops) {
                err = pl->pcs_ops->pcs_config(pl->pcs, pl->cur_link_an_mode,
                                              state->interface,
                                              state->advertising,
                                              !!(pl->link_config.pause &
                                                 MLO_PAUSE_AN));
                if (err < 0)
                        phylink_err(pl, "pcs_config failed: %pe\n",
                                    ERR_PTR(err));
                if (err > 0)
                        restart = true;
        }
        if (restart)
                phylink_mac_pcs_an_restart(pl);

        if (pl->mac_ops->mac_finish) {
                err = pl->mac_ops->mac_finish(pl->config, pl->cur_link_an_mode,
                                              state->interface);
                if (err < 0)
                        phylink_err(pl, "mac_finish failed: %pe\n",
                                    ERR_PTR(err));
        }
}

/*
 * Reconfigure for a change of inband advertisement.
 * If we have a separate PCS, we only need to call its pcs_config() method,
 * and then restart AN if it indicates something changed. Otherwise, we do
 * the full MAC reconfiguration.
 */
static int phylink_change_inband_advert(struct phylink *pl)
{
        int ret;

        if (test_bit(PHYLINK_DISABLE_STOPPED, &pl->phylink_disable_state))
                return 0;

        if (!pl->pcs_ops) {
                /* Legacy method */
                phylink_mac_config(pl, &pl->link_config);
                phylink_mac_pcs_an_restart(pl);
                return 0;
        }

        phylink_dbg(pl, "%s: mode=%s/%s adv=%*pb pause=%02x\n", __func__,
                    phylink_an_mode_str(pl->cur_link_an_mode),
                    phy_modes(pl->link_config.interface),
                    __ETHTOOL_LINK_MODE_MASK_NBITS, pl->link_config.advertising,
                    pl->link_config.pause);

        /* Modern PCS-based method; update the advert at the PCS, and
         * restart negotiation if the pcs_config() helper indicates that
         * the programmed advertisement has changed.
         */
        ret = pl->pcs_ops->pcs_config(pl->pcs, pl->cur_link_an_mode,
                                      pl->link_config.interface,
                                      pl->link_config.advertising,
                                      !!(pl->link_config.pause & MLO_PAUSE_AN));
        if (ret < 0)
                return ret;

        if (ret > 0)
                phylink_mac_pcs_an_restart(pl);

        return 0;
}

static void phylink_mac_pcs_get_state(struct phylink *pl,
                                      struct phylink_link_state *state)
{
        linkmode_copy(state->advertising, pl->link_config.advertising);
        linkmode_zero(state->lp_advertising);
        state->interface = pl->link_config.interface;
        state->an_enabled = pl->link_config.an_enabled;
        state->speed = SPEED_UNKNOWN;
        state->duplex = DUPLEX_UNKNOWN;
        state->pause = MLO_PAUSE_NONE;
        state->an_complete = 0;
        state->link = 1;

        if (pl->pcs_ops)
                pl->pcs_ops->pcs_get_state(pl->pcs, state);
        else if (pl->mac_ops->mac_pcs_get_state)
                pl->mac_ops->mac_pcs_get_state(pl->config, state);
        else
                state->link = 0;
}

/* The fixed state is... fixed except for the link state,
 * which may be determined by a GPIO or a callback.
 */
static void phylink_get_fixed_state(struct phylink *pl,
                                    struct phylink_link_state *state)
{
        *state = pl->link_config;
        if (pl->config->get_fixed_state)
                pl->config->get_fixed_state(pl->config, state);
        else if (pl->link_gpio)
                state->link = !!gpiod_get_value_cansleep(pl->link_gpio);

        phylink_resolve_flow(state);
}

static void phylink_mac_initial_config(struct phylink *pl, bool force_restart)
{
        struct phylink_link_state link_state;

        switch (pl->cur_link_an_mode) {
        case MLO_AN_PHY:
                link_state = pl->phy_state;
                break;

        case MLO_AN_FIXED:
                phylink_get_fixed_state(pl, &link_state);
                break;

        case MLO_AN_INBAND:
                link_state = pl->link_config;
                if (link_state.interface == PHY_INTERFACE_MODE_SGMII)
                        link_state.pause = MLO_PAUSE_NONE;
                break;

        default: /* can't happen */
                return;
        }

        link_state.link = false;

        phylink_apply_manual_flow(pl, &link_state);
        phylink_major_config(pl, force_restart, &link_state);
}

static const char *phylink_pause_to_str(int pause)
{
        switch (pause & MLO_PAUSE_TXRX_MASK) {
        case MLO_PAUSE_TX | MLO_PAUSE_RX:
                return "rx/tx";
        case MLO_PAUSE_TX:
                return "tx";
        case MLO_PAUSE_RX:
                return "rx";
        default:
                return "off";
        }
}

static void phylink_link_up(struct phylink *pl,
                            struct phylink_link_state link_state)
{
        struct net_device *ndev = pl->netdev;

        pl->cur_interface = link_state.interface;

        if (pl->pcs_ops && pl->pcs_ops->pcs_link_up)
                pl->pcs_ops->pcs_link_up(pl->pcs, pl->cur_link_an_mode,
                                         pl->cur_interface,
                                         link_state.speed, link_state.duplex);

        pl->mac_ops->mac_link_up(pl->config, pl->phydev,
                                 pl->cur_link_an_mode, pl->cur_interface,
                                 link_state.speed, link_state.duplex,
                                 !!(link_state.pause & MLO_PAUSE_TX),
                                 !!(link_state.pause & MLO_PAUSE_RX));

        if (ndev)
                netif_carrier_on(ndev);

        phylink_info(pl,
                     "Link is Up - %s/%s - flow control %s\n",
                     phy_speed_to_str(link_state.speed),
                     phy_duplex_to_str(link_state.duplex),
                     phylink_pause_to_str(link_state.pause));
}

static void phylink_link_down(struct phylink *pl)
{
        struct net_device *ndev = pl->netdev;

        if (ndev)
                netif_carrier_off(ndev);
        pl->mac_ops->mac_link_down(pl->config, pl->cur_link_an_mode,
                                   pl->cur_interface);
        phylink_info(pl, "Link is Down\n");
}

static void phylink_resolve(struct work_struct *w)
{
        struct phylink *pl = container_of(w, struct phylink, resolve);
        struct phylink_link_state link_state;
        struct net_device *ndev = pl->netdev;
        bool mac_config = false;
        bool cur_link_state;

        mutex_lock(&pl->state_mutex);
        if (pl->netdev)
                cur_link_state = netif_carrier_ok(ndev);
        else
                cur_link_state = pl->old_link_state;

        if (pl->phylink_disable_state) {
                pl->mac_link_dropped = false;
                link_state.link = false;
        } else if (pl->mac_link_dropped) {
                link_state.link = false;
        } else {
                switch (pl->cur_link_an_mode) {
                case MLO_AN_PHY:
                        link_state = pl->phy_state;
                        phylink_apply_manual_flow(pl, &link_state);
                        mac_config = link_state.link;
                        break;

                case MLO_AN_FIXED:
                        phylink_get_fixed_state(pl, &link_state);
                        mac_config = link_state.link;
                        break;

                case MLO_AN_INBAND:
                        phylink_mac_pcs_get_state(pl, &link_state);

                        /* If we have a phy, the "up" state is the union of
                         * both the PHY and the MAC
                         */
                        if (pl->phydev)
                                link_state.link &= pl->phy_state.link;

                        /* Only update if the PHY link is up */
                        if (pl->phydev && pl->phy_state.link) {
                                link_state.interface = pl->phy_state.interface;

                                /* If we have a PHY, we need to update with
                                 * the PHY flow control bits.
                                 */
                                link_state.pause = pl->phy_state.pause;
                                mac_config = true;
                        }
                        phylink_apply_manual_flow(pl, &link_state);
                        break;
                }
        }

        if (mac_config) {
                if (link_state.interface != pl->link_config.interface) {
                        /* The interface has changed, force the link down and
                         * then reconfigure.
                         */
                        if (cur_link_state) {
                                phylink_link_down(pl);
                                cur_link_state = false;
                        }
                        phylink_major_config(pl, false, &link_state);
                        pl->link_config.interface = link_state.interface;
                } else if (!pl->pcs_ops) {
                        /* The interface remains unchanged, only the speed,
                         * duplex or pause settings have changed. Call the
                         * old mac_config() method to configure the MAC/PCS
                         * only if we do not have a PCS installed (an
                         * unconverted user.)
                         */
                        phylink_mac_config(pl, &link_state);
                }
        }

        if (link_state.link != cur_link_state) {
                pl->old_link_state = link_state.link;
                if (!link_state.link)
                        phylink_link_down(pl);
                else
                        phylink_link_up(pl, link_state);
        }
        if (!link_state.link && pl->mac_link_dropped) {
                pl->mac_link_dropped = false;
                queue_work(system_power_efficient_wq, &pl->resolve);
        }
        mutex_unlock(&pl->state_mutex);
}

static void phylink_run_resolve(struct phylink *pl)
{
        if (!pl->phylink_disable_state)
                queue_work(system_power_efficient_wq, &pl->resolve);
}

static void phylink_run_resolve_and_disable(struct phylink *pl, int bit)
{
        unsigned long state = pl->phylink_disable_state;

        set_bit(bit, &pl->phylink_disable_state);
        if (state == 0) {
                queue_work(system_power_efficient_wq, &pl->resolve);
                flush_work(&pl->resolve);
        }
}

static void phylink_fixed_poll(struct timer_list *t)
{
        struct phylink *pl = container_of(t, struct phylink, link_poll);

        mod_timer(t, jiffies + HZ);

        phylink_run_resolve(pl);
}

static const struct sfp_upstream_ops sfp_phylink_ops;

static int phylink_register_sfp(struct phylink *pl,
                                struct fwnode_handle *fwnode)
{
        struct sfp_bus *bus;
        int ret;

        if (!fwnode)
                return 0;

        bus = sfp_bus_find_fwnode(fwnode);
        if (IS_ERR(bus)) {
                ret = PTR_ERR(bus);
                phylink_err(pl, "unable to attach SFP bus: %d\n", ret);
                return ret;
        }

        pl->sfp_bus = bus;

        ret = sfp_bus_add_upstream(bus, pl, &sfp_phylink_ops);
        sfp_bus_put(bus);

        return ret;
}

/**
 * phylink_create() - create a phylink instance
 * @config: a pointer to the target &struct phylink_config
 * @fwnode: a pointer to a &struct fwnode_handle describing the network
 *      interface
 * @iface: the desired link mode defined by &typedef phy_interface_t
 * @mac_ops: a pointer to a &struct phylink_mac_ops for the MAC.
 *
 * Create a new phylink instance, and parse the link parameters found in @np.
 * This will parse in-band modes, fixed-link or SFP configuration.
 *
 * Note: the rtnl lock must not be held when calling this function.
 *
 * Returns a pointer to a &struct phylink, or an error-pointer value. Users
 * must use IS_ERR() to check for errors from this function.
 */
struct phylink *phylink_create(struct phylink_config *config,
                               struct fwnode_handle *fwnode,
                               phy_interface_t iface,
                               const struct phylink_mac_ops *mac_ops)
{
        struct phylink *pl;
        int ret;

        pl = kzalloc(sizeof(*pl), GFP_KERNEL);
        if (!pl)
                return ERR_PTR(-ENOMEM);

        mutex_init(&pl->state_mutex);
        INIT_WORK(&pl->resolve, phylink_resolve);

        pl->config = config;
        if (config->type == PHYLINK_NETDEV) {
                pl->netdev = to_net_dev(config->dev);
        } else if (config->type == PHYLINK_DEV) {
                pl->dev = config->dev;
        } else {
                kfree(pl);
                return ERR_PTR(-EINVAL);
        }

        pl->phy_state.interface = iface;
        pl->link_interface = iface;
        if (iface == PHY_INTERFACE_MODE_MOCA)
                pl->link_port = PORT_BNC;
        else
                pl->link_port = PORT_MII;
        pl->link_config.interface = iface;
        pl->link_config.pause = MLO_PAUSE_AN;
        pl->link_config.speed = SPEED_UNKNOWN;
        pl->link_config.duplex = DUPLEX_UNKNOWN;
        pl->link_config.an_enabled = true;
        pl->mac_ops = mac_ops;
        __set_bit(PHYLINK_DISABLE_STOPPED, &pl->phylink_disable_state);
        timer_setup(&pl->link_poll, phylink_fixed_poll, 0);

        bitmap_fill(pl->supported, __ETHTOOL_LINK_MODE_MASK_NBITS);
        linkmode_copy(pl->link_config.advertising, pl->supported);
        phylink_validate(pl, pl->supported, &pl->link_config);

        ret = phylink_parse_mode(pl, fwnode);
        if (ret < 0) {
                kfree(pl);
                return ERR_PTR(ret);
        }

        if (pl->cfg_link_an_mode == MLO_AN_FIXED) {
                ret = phylink_parse_fixedlink(pl, fwnode);
                if (ret < 0) {
                        kfree(pl);
                        return ERR_PTR(ret);
                }
        }

        pl->cur_link_an_mode = pl->cfg_link_an_mode;

        ret = phylink_register_sfp(pl, fwnode);
        if (ret < 0) {
                kfree(pl);
                return ERR_PTR(ret);
        }

        return pl;
}
EXPORT_SYMBOL_GPL(phylink_create);

/**
 * phylink_set_pcs() - set the current PCS for phylink to use
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @pcs: a pointer to the &struct phylink_pcs
 *
 * Bind the MAC PCS to phylink.  This may be called after phylink_create(),
 * in mac_prepare() or mac_config() methods if it is desired to dynamically
 * change the PCS.
 *
 * Please note that there are behavioural changes with the mac_config()
 * callback if a PCS is present (denoting a newer setup) so removing a PCS
 * is not supported, and if a PCS is going to be used, it must be registered
 * by calling phylink_set_pcs() at the latest in the first mac_config() call.
 */
void phylink_set_pcs(struct phylink *pl, struct phylink_pcs *pcs)
{
        pl->pcs = pcs;
        pl->pcs_ops = pcs->ops;
}
EXPORT_SYMBOL_GPL(phylink_set_pcs);

/**
 * phylink_destroy() - cleanup and destroy the phylink instance
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 *
 * Destroy a phylink instance. Any PHY that has been attached must have been
 * cleaned up via phylink_disconnect_phy() prior to calling this function.
 *
 * Note: the rtnl lock must not be held when calling this function.
 */
void phylink_destroy(struct phylink *pl)
{
        sfp_bus_del_upstream(pl->sfp_bus);
        if (pl->link_gpio)
                gpiod_put(pl->link_gpio);

        cancel_work_sync(&pl->resolve);
        kfree(pl);
}
EXPORT_SYMBOL_GPL(phylink_destroy);

static void phylink_phy_change(struct phy_device *phydev, bool up)
{
        struct phylink *pl = phydev->phylink;
        bool tx_pause, rx_pause;

        phy_get_pause(phydev, &tx_pause, &rx_pause);

        mutex_lock(&pl->state_mutex);
        pl->phy_state.speed = phydev->speed;
        pl->phy_state.duplex = phydev->duplex;
        pl->phy_state.pause = MLO_PAUSE_NONE;
        if (tx_pause)
                pl->phy_state.pause |= MLO_PAUSE_TX;
        if (rx_pause)
                pl->phy_state.pause |= MLO_PAUSE_RX;
        pl->phy_state.interface = phydev->interface;
        pl->phy_state.link = up;
        mutex_unlock(&pl->state_mutex);

        phylink_run_resolve(pl);

        phylink_dbg(pl, "phy link %s %s/%s/%s/%s\n", up ? "up" : "down",
                    phy_modes(phydev->interface),
                    phy_speed_to_str(phydev->speed),
                    phy_duplex_to_str(phydev->duplex),
                    phylink_pause_to_str(pl->phy_state.pause));
}

static int phylink_bringup_phy(struct phylink *pl, struct phy_device *phy,
                               phy_interface_t interface)
{
        struct phylink_link_state config;
        __ETHTOOL_DECLARE_LINK_MODE_MASK(supported);
        char *irq_str;
        int ret;

        /*
         * This is the new way of dealing with flow control for PHYs,
         * as described by Timur Tabi in commit 529ed1275263 ("net: phy:
         * phy drivers should not set SUPPORTED_[Asym_]Pause") except
         * using our validate call to the MAC, we rely upon the MAC
         * clearing the bits from both supported and advertising fields.
         */
        phy_support_asym_pause(phy);

        memset(&config, 0, sizeof(config));
        linkmode_copy(supported, phy->supported);
        linkmode_copy(config.advertising, phy->advertising);

        /* Clause 45 PHYs switch their Serdes lane between several different
         * modes, normally 10GBASE-R, SGMII. Some use 2500BASE-X for 2.5G
         * speeds. We really need to know which interface modes the PHY and
         * MAC supports to properly work out which linkmodes can be supported.
         */
        if (phy->is_c45 &&
            interface != PHY_INTERFACE_MODE_RXAUI &&
            interface != PHY_INTERFACE_MODE_XAUI &&
            interface != PHY_INTERFACE_MODE_USXGMII)
                config.interface = PHY_INTERFACE_MODE_NA;
        else
                config.interface = interface;

        ret = phylink_validate(pl, supported, &config);
        if (ret) {
                phylink_warn(pl, "validation of %s with support %*pb and advertisement %*pb failed: %d\n",
                             phy_modes(config.interface),
                             __ETHTOOL_LINK_MODE_MASK_NBITS, phy->supported,
                             __ETHTOOL_LINK_MODE_MASK_NBITS, config.advertising,
                             ret);
                return ret;
        }

        phy->phylink = pl;
        phy->phy_link_change = phylink_phy_change;

        irq_str = phy_attached_info_irq(phy);

        phylink_info(pl,
                     "PHY [%s] driver [%s] (irq=%s)\n",
                     dev_name(&phy->mdio.dev), phy->drv->name, irq_str);
        kfree(irq_str);

        mutex_lock(&phy->lock);
        mutex_lock(&pl->state_mutex);
        pl->phydev = phy;
        pl->phy_state.interface = interface;
        pl->phy_state.pause = MLO_PAUSE_NONE;
        pl->phy_state.speed = SPEED_UNKNOWN;
        pl->phy_state.duplex = DUPLEX_UNKNOWN;
        linkmode_copy(pl->supported, supported);
        linkmode_copy(pl->link_config.advertising, config.advertising);

        /* Restrict the phy advertisement according to the MAC support. */
        linkmode_copy(phy->advertising, config.advertising);
        mutex_unlock(&pl->state_mutex);
        mutex_unlock(&phy->lock);

        phylink_dbg(pl,
                    "phy: setting supported %*pb advertising %*pb\n",
                    __ETHTOOL_LINK_MODE_MASK_NBITS, pl->supported,
                    __ETHTOOL_LINK_MODE_MASK_NBITS, phy->advertising);

        if (phy_interrupt_is_valid(phy))
                phy_request_interrupt(phy);

        return 0;
}

static int phylink_attach_phy(struct phylink *pl, struct phy_device *phy,
                              phy_interface_t interface)
{
        if (WARN_ON(pl->cfg_link_an_mode == MLO_AN_FIXED ||
                    (pl->cfg_link_an_mode == MLO_AN_INBAND &&
                     phy_interface_mode_is_8023z(interface))))
                return -EINVAL;

        if (pl->phydev)
                return -EBUSY;

        return phy_attach_direct(pl->netdev, phy, 0, interface);
}

/**
 * phylink_connect_phy() - connect a PHY to the phylink instance
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @phy: a pointer to a &struct phy_device.
 *
 * Connect @phy to the phylink instance specified by @pl by calling
 * phy_attach_direct(). Configure the @phy according to the MAC driver's
 * capabilities, start the PHYLIB state machine and enable any interrupts
 * that the PHY supports.
 *
 * This updates the phylink's ethtool supported and advertising link mode
 * masks.
 *
 * Returns 0 on success or a negative errno.
 */
int phylink_connect_phy(struct phylink *pl, struct phy_device *phy)
{
        int ret;

        /* Use PHY device/driver interface */
        if (pl->link_interface == PHY_INTERFACE_MODE_NA) {
                pl->link_interface = phy->interface;
                pl->link_config.interface = pl->link_interface;
        }

        ret = phylink_attach_phy(pl, phy, pl->link_interface);
        if (ret < 0)
                return ret;

        ret = phylink_bringup_phy(pl, phy, pl->link_config.interface);
        if (ret)
                phy_detach(phy);

        return ret;
}
EXPORT_SYMBOL_GPL(phylink_connect_phy);

/**
 * phylink_of_phy_connect() - connect the PHY specified in the DT mode.
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @dn: a pointer to a &struct device_node.
 * @flags: PHY-specific flags to communicate to the PHY device driver
 *
 * Connect the phy specified in the device node @dn to the phylink instance
 * specified by @pl. Actions specified in phylink_connect_phy() will be
 * performed.
 *
 * Returns 0 on success or a negative errno.
 */
int phylink_of_phy_connect(struct phylink *pl, struct device_node *dn,
                           u32 flags)
{
        return phylink_fwnode_phy_connect(pl, of_fwnode_handle(dn), flags);
}
EXPORT_SYMBOL_GPL(phylink_of_phy_connect);

/**
 * phylink_fwnode_phy_connect() - connect the PHY specified in the fwnode.
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @fwnode: a pointer to a &struct fwnode_handle.
 * @flags: PHY-specific flags to communicate to the PHY device driver
 *
 * Connect the phy specified @fwnode to the phylink instance specified
 * by @pl.
 *
 * Returns 0 on success or a negative errno.
 */
int phylink_fwnode_phy_connect(struct phylink *pl,
                               struct fwnode_handle *fwnode,
                               u32 flags)
{
        struct fwnode_handle *phy_fwnode;
        struct phy_device *phy_dev;
        int ret;

        /* Fixed links and 802.3z are handled without needing a PHY */
        if (pl->cfg_link_an_mode == MLO_AN_FIXED ||
            (pl->cfg_link_an_mode == MLO_AN_INBAND &&
             phy_interface_mode_is_8023z(pl->link_interface)))
                return 0;

        phy_fwnode = fwnode_get_phy_node(fwnode);
        if (IS_ERR(phy_fwnode)) {
                if (pl->cfg_link_an_mode == MLO_AN_PHY)
                        return -ENODEV;
                return 0;
        }

        phy_dev = fwnode_phy_find_device(phy_fwnode);
        /* We're done with the phy_node handle */
        fwnode_handle_put(phy_fwnode);
        if (!phy_dev)
                return -ENODEV;

        ret = phy_attach_direct(pl->netdev, phy_dev, flags,
                                pl->link_interface);
        if (ret) {
                phy_device_free(phy_dev);
                return ret;
        }

        ret = phylink_bringup_phy(pl, phy_dev, pl->link_config.interface);
        if (ret)
                phy_detach(phy_dev);

        return ret;
}
EXPORT_SYMBOL_GPL(phylink_fwnode_phy_connect);

/**
 * phylink_disconnect_phy() - disconnect any PHY attached to the phylink
 *   instance.
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 *
 * Disconnect any current PHY from the phylink instance described by @pl.
 */
void phylink_disconnect_phy(struct phylink *pl)
{
        struct phy_device *phy;

        ASSERT_RTNL();

        phy = pl->phydev;
        if (phy) {
                mutex_lock(&phy->lock);
                mutex_lock(&pl->state_mutex);
                pl->phydev = NULL;
                mutex_unlock(&pl->state_mutex);
                mutex_unlock(&phy->lock);
                flush_work(&pl->resolve);

                phy_disconnect(phy);
        }
}
EXPORT_SYMBOL_GPL(phylink_disconnect_phy);

/**
 * phylink_mac_change() - notify phylink of a change in MAC state
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @up: indicates whether the link is currently up.
 *
 * The MAC driver should call this driver when the state of its link
 * changes (eg, link failure, new negotiation results, etc.)
 */
void phylink_mac_change(struct phylink *pl, bool up)
{
        if (!up)
                pl->mac_link_dropped = true;
        phylink_run_resolve(pl);
        phylink_dbg(pl, "mac link %s\n", up ? "up" : "down");
}
EXPORT_SYMBOL_GPL(phylink_mac_change);

static irqreturn_t phylink_link_handler(int irq, void *data)
{
        struct phylink *pl = data;

        phylink_run_resolve(pl);

        return IRQ_HANDLED;
}

/**
 * phylink_start() - start a phylink instance
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 *
 * Start the phylink instance specified by @pl, configuring the MAC for the
 * desired link mode(s) and negotiation style. This should be called from the
 * network device driver's &struct net_device_ops ndo_open() method.
 */
void phylink_start(struct phylink *pl)
{
        bool poll = false;

        ASSERT_RTNL();

        phylink_info(pl, "configuring for %s/%s link mode\n",
                     phylink_an_mode_str(pl->cur_link_an_mode),
                     phy_modes(pl->link_config.interface));

        /* Always set the carrier off */
        if (pl->netdev)
                netif_carrier_off(pl->netdev);

        /* Apply the link configuration to the MAC when starting. This allows
         * a fixed-link to start with the correct parameters, and also
         * ensures that we set the appropriate advertisement for Serdes links.
         *
         * Restart autonegotiation if using 802.3z to ensure that the link
         * parameters are properly negotiated.  This is necessary for DSA
         * switches using 802.3z negotiation to ensure they see our modes.
         */
        phylink_mac_initial_config(pl, true);

        clear_bit(PHYLINK_DISABLE_STOPPED, &pl->phylink_disable_state);
        phylink_run_resolve(pl);

        if (pl->cfg_link_an_mode == MLO_AN_FIXED && pl->link_gpio) {
                int irq = gpiod_to_irq(pl->link_gpio);

                if (irq > 0) {
                        if (!request_irq(irq, phylink_link_handler,
                                         IRQF_TRIGGER_RISING |
                                         IRQF_TRIGGER_FALLING,
                                         "netdev link", pl))
                                pl->link_irq = irq;
                        else
                                irq = 0;
                }
                if (irq <= 0)
                        poll = true;
        }

        switch (pl->cfg_link_an_mode) {
        case MLO_AN_FIXED:
                poll |= pl->config->poll_fixed_state;
                break;
        case MLO_AN_INBAND:
                poll |= pl->config->pcs_poll;
                if (pl->pcs)
                        poll |= pl->pcs->poll;
                break;
        }
        if (poll)
                mod_timer(&pl->link_poll, jiffies + HZ);
        if (pl->phydev)
                phy_start(pl->phydev);
        if (pl->sfp_bus)
                sfp_upstream_start(pl->sfp_bus);
}
EXPORT_SYMBOL_GPL(phylink_start);

/**
 * phylink_stop() - stop a phylink instance
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 *
 * Stop the phylink instance specified by @pl. This should be called from the
 * network device driver's &struct net_device_ops ndo_stop() method.  The
 * network device's carrier state should not be changed prior to calling this
 * function.
 *
 * This will synchronously bring down the link if the link is not already
 * down (in other words, it will trigger a mac_link_down() method call.)
 */
void phylink_stop(struct phylink *pl)
{
        ASSERT_RTNL();

        if (pl->sfp_bus)
                sfp_upstream_stop(pl->sfp_bus);
        if (pl->phydev)
                phy_stop(pl->phydev);
        del_timer_sync(&pl->link_poll);
        if (pl->link_irq) {
                free_irq(pl->link_irq, pl);
                pl->link_irq = 0;
        }

        phylink_run_resolve_and_disable(pl, PHYLINK_DISABLE_STOPPED);
}
EXPORT_SYMBOL_GPL(phylink_stop);

/**
 * phylink_suspend() - handle a network device suspend event
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @mac_wol: true if the MAC needs to receive packets for Wake-on-Lan
 *
 * Handle a network device suspend event. There are several cases:
 * - If Wake-on-Lan is not active, we can bring down the link between
 *   the MAC and PHY by calling phylink_stop().
 * - If Wake-on-Lan is active, and being handled only by the PHY, we
 *   can also bring down the link between the MAC and PHY.
 * - If Wake-on-Lan is active, but being handled by the MAC, the MAC
 *   still needs to receive packets, so we can not bring the link down.
 */
void phylink_suspend(struct phylink *pl, bool mac_wol)
{
        ASSERT_RTNL();

        if (mac_wol && (!pl->netdev || pl->netdev->wol_enabled)) {
                /* Wake-on-Lan enabled, MAC handling */
                mutex_lock(&pl->state_mutex);

                /* Stop the resolver bringing the link up */
                __set_bit(PHYLINK_DISABLE_MAC_WOL, &pl->phylink_disable_state);

                /* Disable the carrier, to prevent transmit timeouts,
                 * but one would hope all packets have been sent. This
                 * also means phylink_resolve() will do nothing.
                 */
                netif_carrier_off(pl->netdev);

                /* We do not call mac_link_down() here as we want the
                 * link to remain up to receive the WoL packets.
                 */
                mutex_unlock(&pl->state_mutex);
        } else {
                phylink_stop(pl);
        }
}
EXPORT_SYMBOL_GPL(phylink_suspend);

/**
 * phylink_resume() - handle a network device resume event
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 *
 * Undo the effects of phylink_suspend(), returning the link to an
 * operational state.
 */
void phylink_resume(struct phylink *pl)
{
        ASSERT_RTNL();

        if (test_bit(PHYLINK_DISABLE_MAC_WOL, &pl->phylink_disable_state)) {
                /* Wake-on-Lan enabled, MAC handling */

                /* Call mac_link_down() so we keep the overall state balanced.
                 * Do this under the state_mutex lock for consistency. This
                 * will cause a "Link Down" message to be printed during
                 * resume, which is harmless - the true link state will be
                 * printed when we run a resolve.
                 */
                mutex_lock(&pl->state_mutex);
                phylink_link_down(pl);
                mutex_unlock(&pl->state_mutex);

                /* Re-apply the link parameters so that all the settings get
                 * restored to the MAC.
                 */
                phylink_mac_initial_config(pl, true);

                /* Re-enable and re-resolve the link parameters */
                clear_bit(PHYLINK_DISABLE_MAC_WOL, &pl->phylink_disable_state);
                phylink_run_resolve(pl);
        } else {
                phylink_start(pl);
        }
}
EXPORT_SYMBOL_GPL(phylink_resume);

/**
 * phylink_ethtool_get_wol() - get the wake on lan parameters for the PHY
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @wol: a pointer to &struct ethtool_wolinfo to hold the read parameters
 *
 * Read the wake on lan parameters from the PHY attached to the phylink
 * instance specified by @pl. If no PHY is currently attached, report no
 * support for wake on lan.
 */
void phylink_ethtool_get_wol(struct phylink *pl, struct ethtool_wolinfo *wol)
{
        ASSERT_RTNL();

        wol->supported = 0;
        wol->wolopts = 0;

        if (pl->phydev)
                phy_ethtool_get_wol(pl->phydev, wol);
}
EXPORT_SYMBOL_GPL(phylink_ethtool_get_wol);

/**
 * phylink_ethtool_set_wol() - set wake on lan parameters
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @wol: a pointer to &struct ethtool_wolinfo for the desired parameters
 *
 * Set the wake on lan parameters for the PHY attached to the phylink
 * instance specified by @pl. If no PHY is attached, returns %EOPNOTSUPP
 * error.
 *
 * Returns zero on success or negative errno code.
 */
int phylink_ethtool_set_wol(struct phylink *pl, struct ethtool_wolinfo *wol)
{
        int ret = -EOPNOTSUPP;

        ASSERT_RTNL();

        if (pl->phydev)
                ret = phy_ethtool_set_wol(pl->phydev, wol);

        return ret;
}
EXPORT_SYMBOL_GPL(phylink_ethtool_set_wol);

static void phylink_merge_link_mode(unsigned long *dst, const unsigned long *b)
{
        __ETHTOOL_DECLARE_LINK_MODE_MASK(mask);

        linkmode_zero(mask);
        phylink_set_port_modes(mask);

        linkmode_and(dst, dst, mask);
        linkmode_or(dst, dst, b);
}

static void phylink_get_ksettings(const struct phylink_link_state *state,
                                  struct ethtool_link_ksettings *kset)
{
        phylink_merge_link_mode(kset->link_modes.advertising, state->advertising);
        linkmode_copy(kset->link_modes.lp_advertising, state->lp_advertising);
        kset->base.speed = state->speed;
        kset->base.duplex = state->duplex;
        kset->base.autoneg = state->an_enabled ? AUTONEG_ENABLE :
                                AUTONEG_DISABLE;
}

/**
 * phylink_ethtool_ksettings_get() - get the current link settings
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @kset: a pointer to a &struct ethtool_link_ksettings to hold link settings
 *
 * Read the current link settings for the phylink instance specified by @pl.
 * This will be the link settings read from the MAC, PHY or fixed link
 * settings depending on the current negotiation mode.
 */
int phylink_ethtool_ksettings_get(struct phylink *pl,
                                  struct ethtool_link_ksettings *kset)
{
        struct phylink_link_state link_state;

        ASSERT_RTNL();

        if (pl->phydev)
                phy_ethtool_ksettings_get(pl->phydev, kset);
        else
                kset->base.port = pl->link_port;

        linkmode_copy(kset->link_modes.supported, pl->supported);

        switch (pl->cur_link_an_mode) {
        case MLO_AN_FIXED:
                /* We are using fixed settings. Report these as the
                 * current link settings - and note that these also
                 * represent the supported speeds/duplex/pause modes.
                 */
                phylink_get_fixed_state(pl, &link_state);
                phylink_get_ksettings(&link_state, kset);
                break;

        case MLO_AN_INBAND:
                /* If there is a phy attached, then use the reported
                 * settings from the phy with no modification.
                 */
                if (pl->phydev)
                        break;

                phylink_mac_pcs_get_state(pl, &link_state);

                /* The MAC is reporting the link results from its own PCS
                 * layer via in-band status. Report these as the current
                 * link settings.
                 */
                phylink_get_ksettings(&link_state, kset);
                break;
        }

        return 0;
}
EXPORT_SYMBOL_GPL(phylink_ethtool_ksettings_get);

/**
 * phylink_ethtool_ksettings_set() - set the link settings
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @kset: a pointer to a &struct ethtool_link_ksettings for the desired modes
 */
int phylink_ethtool_ksettings_set(struct phylink *pl,
                                  const struct ethtool_link_ksettings *kset)
{
        __ETHTOOL_DECLARE_LINK_MODE_MASK(support);
        struct phylink_link_state config;
        const struct phy_setting *s;

        ASSERT_RTNL();

        if (pl->phydev) {
                /* We can rely on phylib for this update; we also do not need
                 * to update the pl->link_config settings:
                 * - the configuration returned via ksettings_get() will come
                 *   from phylib whenever a PHY is present.
                 * - link_config.interface will be updated by the PHY calling
                 *   back via phylink_phy_change() and a subsequent resolve.
                 * - initial link configuration for PHY mode comes from the
                 *   last phy state updated via phylink_phy_change().
                 * - other configuration changes (e.g. pause modes) are
                 *   performed directly via phylib.
                 * - if in in-band mode with a PHY, the link configuration
                 *   is passed on the link from the PHY, and all of
                 *   link_config.{speed,duplex,an_enabled,pause} are not used.
                 * - the only possible use would be link_config.advertising
                 *   pause modes when in 1000base-X mode with a PHY, but in
                 *   the presence of a PHY, this should not be changed as that
                 *   should be determined from the media side advertisement.
                 */
                return phy_ethtool_ksettings_set(pl->phydev, kset);
        }

        config = pl->link_config;

        /* Mask out unsupported advertisements */
        linkmode_and(config.advertising, kset->link_modes.advertising,
                     pl->supported);

        /* FIXME: should we reject autoneg if phy/mac does not support it? */
        switch (kset->base.autoneg) {
        case AUTONEG_DISABLE:
                /* Autonegotiation disabled, select a suitable speed and
                 * duplex.
                 */
                s = phy_lookup_setting(kset->base.speed, kset->base.duplex,
                                       pl->supported, false);
                if (!s)
                        return -EINVAL;

                /* If we have a fixed link, refuse to change link parameters.
                 * If the link parameters match, accept them but do nothing.
                 */
                if (pl->cur_link_an_mode == MLO_AN_FIXED) {
                        if (s->speed != pl->link_config.speed ||
                            s->duplex != pl->link_config.duplex)
                                return -EINVAL;
                        return 0;
                }

                config.speed = s->speed;
                config.duplex = s->duplex;
                break;

        case AUTONEG_ENABLE:
                /* If we have a fixed link, allow autonegotiation (since that
                 * is our default case) but do not allow the advertisement to
                 * be changed. If the advertisement matches, simply return.
                 */
                if (pl->cur_link_an_mode == MLO_AN_FIXED) {
                        if (!linkmode_equal(config.advertising,
                                            pl->link_config.advertising))
                                return -EINVAL;
                        return 0;
                }

                config.speed = SPEED_UNKNOWN;
                config.duplex = DUPLEX_UNKNOWN;
                break;

        default:
                return -EINVAL;
        }

        /* We have ruled out the case with a PHY attached, and the
         * fixed-link cases.  All that is left are in-band links.
         */
        config.an_enabled = kset->base.autoneg == AUTONEG_ENABLE;
        linkmode_mod_bit(ETHTOOL_LINK_MODE_Autoneg_BIT, config.advertising,
                         config.an_enabled);

        /* Validate without changing the current supported mask. */
        linkmode_copy(support, pl->supported);
        if (phylink_validate(pl, support, &config))
                return -EINVAL;

        /* If autonegotiation is enabled, we must have an advertisement */
        if (config.an_enabled && phylink_is_empty_linkmode(config.advertising))
                return -EINVAL;

        /* If this link is with an SFP, ensure that changes to advertised modes
         * also cause the associated interface to be selected such that the
         * link can be configured correctly.
         */
        if (pl->sfp_port && pl->sfp_bus) {
                config.interface = sfp_select_interface(pl->sfp_bus,
                                                        config.advertising);
                if (config.interface == PHY_INTERFACE_MODE_NA) {
                        phylink_err(pl,
                                    "selection of interface failed, advertisement %*pb\n",
                                    __ETHTOOL_LINK_MODE_MASK_NBITS,
                                    config.advertising);
                        return -EINVAL;
                }

                /* Revalidate with the selected interface */
                linkmode_copy(support, pl->supported);
                if (phylink_validate(pl, support, &config)) {
                        phylink_err(pl, "validation of %s/%s with support %*pb failed\n",
                                    phylink_an_mode_str(pl->cur_link_an_mode),
                                    phy_modes(config.interface),
                                    __ETHTOOL_LINK_MODE_MASK_NBITS, support);
                        return -EINVAL;
                }
        }

        mutex_lock(&pl->state_mutex);
        pl->link_config.speed = config.speed;
        pl->link_config.duplex = config.duplex;
        pl->link_config.an_enabled = config.an_enabled;

        if (pl->link_config.interface != config.interface) {
                /* The interface changed, e.g. 1000base-X <-> 2500base-X */
                /* We need to force the link down, then change the interface */
                if (pl->old_link_state) {
                        phylink_link_down(pl);
                        pl->old_link_state = false;
                }
                if (!test_bit(PHYLINK_DISABLE_STOPPED,
                              &pl->phylink_disable_state))
                        phylink_major_config(pl, false, &config);
                pl->link_config.interface = config.interface;
                linkmode_copy(pl->link_config.advertising, config.advertising);
        } else if (!linkmode_equal(pl->link_config.advertising,
                                   config.advertising)) {
                linkmode_copy(pl->link_config.advertising, config.advertising);
                phylink_change_inband_advert(pl);
        }
        mutex_unlock(&pl->state_mutex);

        return 0;
}
EXPORT_SYMBOL_GPL(phylink_ethtool_ksettings_set);

/**
 * phylink_ethtool_nway_reset() - restart negotiation
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 *
 * Restart negotiation for the phylink instance specified by @pl. This will
 * cause any attached phy to restart negotiation with the link partner, and
 * if the MAC is in a BaseX mode, the MAC will also be requested to restart
 * negotiation.
 *
 * Returns zero on success, or negative error code.
 */
int phylink_ethtool_nway_reset(struct phylink *pl)
{
        int ret = 0;

        ASSERT_RTNL();

        if (pl->phydev)
                ret = phy_restart_aneg(pl->phydev);
        phylink_mac_pcs_an_restart(pl);

        return ret;
}
EXPORT_SYMBOL_GPL(phylink_ethtool_nway_reset);

/**
 * phylink_ethtool_get_pauseparam() - get the current pause parameters
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @pause: a pointer to a &struct ethtool_pauseparam
 */
void phylink_ethtool_get_pauseparam(struct phylink *pl,
                                    struct ethtool_pauseparam *pause)
{
        ASSERT_RTNL();

        pause->autoneg = !!(pl->link_config.pause & MLO_PAUSE_AN);
        pause->rx_pause = !!(pl->link_config.pause & MLO_PAUSE_RX);
        pause->tx_pause = !!(pl->link_config.pause & MLO_PAUSE_TX);
}
EXPORT_SYMBOL_GPL(phylink_ethtool_get_pauseparam);

/**
 * phylink_ethtool_set_pauseparam() - set the current pause parameters
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @pause: a pointer to a &struct ethtool_pauseparam
 */
int phylink_ethtool_set_pauseparam(struct phylink *pl,
                                   struct ethtool_pauseparam *pause)
{
        struct phylink_link_state *config = &pl->link_config;
        bool manual_changed;
        int pause_state;

        ASSERT_RTNL();

        if (pl->cur_link_an_mode == MLO_AN_FIXED)
                return -EOPNOTSUPP;

        if (!phylink_test(pl->supported, Pause) &&
            !phylink_test(pl->supported, Asym_Pause))
                return -EOPNOTSUPP;

        if (!phylink_test(pl->supported, Asym_Pause) &&
            !pause->autoneg && pause->rx_pause != pause->tx_pause)
                return -EINVAL;

        pause_state = 0;
        if (pause->autoneg)
                pause_state |= MLO_PAUSE_AN;
        if (pause->rx_pause)
                pause_state |= MLO_PAUSE_RX;
        if (pause->tx_pause)
                pause_state |= MLO_PAUSE_TX;

        mutex_lock(&pl->state_mutex);
        /*
         * See the comments for linkmode_set_pause(), wrt the deficiencies
         * with the current implementation.  A solution to this issue would
         * be:
         * ethtool  Local device
         *  rx  tx  Pause AsymDir
         *  0   0   0     0
         *  1   0   1     1
         *  0   1   0     1
         *  1   1   1     1
         * and then use the ethtool rx/tx enablement status to mask the
         * rx/tx pause resolution.
         */
        linkmode_set_pause(config->advertising, pause->tx_pause,
                           pause->rx_pause);

        manual_changed = (config->pause ^ pause_state) & MLO_PAUSE_AN ||
                         (!(pause_state & MLO_PAUSE_AN) &&
                           (config->pause ^ pause_state) & MLO_PAUSE_TXRX_MASK);

        config->pause = pause_state;

        /* Update our in-band advertisement, triggering a renegotiation if
         * the advertisement changed.
         */
        if (!pl->phydev)
                phylink_change_inband_advert(pl);

        mutex_unlock(&pl->state_mutex);

        /* If we have a PHY, a change of the pause frame advertisement will
         * cause phylib to renegotiate (if AN is enabled) which will in turn
         * call our phylink_phy_change() and trigger a resolve.  Note that
         * we can't hold our state mutex while calling phy_set_asym_pause().
         */
        if (pl->phydev)
                phy_set_asym_pause(pl->phydev, pause->rx_pause,
                                   pause->tx_pause);

        /* If the manual pause settings changed, make sure we trigger a
         * resolve to update their state; we can not guarantee that the
         * link will cycle.
         */
        if (manual_changed) {
                pl->mac_link_dropped = true;
                phylink_run_resolve(pl);
        }

        return 0;
}
EXPORT_SYMBOL_GPL(phylink_ethtool_set_pauseparam);

/**
 * phylink_get_eee_err() - read the energy efficient ethernet error
 *   counter
 * @pl: a pointer to a &struct phylink returned from phylink_create().
 *
 * Read the Energy Efficient Ethernet error counter from the PHY associated
 * with the phylink instance specified by @pl.
 *
 * Returns positive error counter value, or negative error code.
 */
int phylink_get_eee_err(struct phylink *pl)
{
        int ret = 0;

        ASSERT_RTNL();

        if (pl->phydev)
                ret = phy_get_eee_err(pl->phydev);

        return ret;
}
EXPORT_SYMBOL_GPL(phylink_get_eee_err);

/**
 * phylink_init_eee() - init and check the EEE features
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @clk_stop_enable: allow PHY to stop receive clock
 *
 * Must be called either with RTNL held or within mac_link_up()
 */
int phylink_init_eee(struct phylink *pl, bool clk_stop_enable)
{
        int ret = -EOPNOTSUPP;

        if (pl->phydev)
                ret = phy_init_eee(pl->phydev, clk_stop_enable);

        return ret;
}
EXPORT_SYMBOL_GPL(phylink_init_eee);

/**
 * phylink_ethtool_get_eee() - read the energy efficient ethernet parameters
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @eee: a pointer to a &struct ethtool_eee for the read parameters
 */
int phylink_ethtool_get_eee(struct phylink *pl, struct ethtool_eee *eee)
{
        int ret = -EOPNOTSUPP;

        ASSERT_RTNL();

        if (pl->phydev)
                ret = phy_ethtool_get_eee(pl->phydev, eee);

        return ret;
}
EXPORT_SYMBOL_GPL(phylink_ethtool_get_eee);

/**
 * phylink_ethtool_set_eee() - set the energy efficient ethernet parameters
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @eee: a pointer to a &struct ethtool_eee for the desired parameters
 */
int phylink_ethtool_set_eee(struct phylink *pl, struct ethtool_eee *eee)
{
        int ret = -EOPNOTSUPP;

        ASSERT_RTNL();

        if (pl->phydev)
                ret = phy_ethtool_set_eee(pl->phydev, eee);

        return ret;
}
EXPORT_SYMBOL_GPL(phylink_ethtool_set_eee);

/* This emulates MII registers for a fixed-mode phy operating as per the
 * passed in state. "aneg" defines if we report negotiation is possible.
 *
 * FIXME: should deal with negotiation state too.
 */
static int phylink_mii_emul_read(unsigned int reg,
                                 struct phylink_link_state *state)
{
        struct fixed_phy_status fs;
        unsigned long *lpa = state->lp_advertising;
        int val;

        fs.link = state->link;
        fs.speed = state->speed;
        fs.duplex = state->duplex;
        fs.pause = test_bit(ETHTOOL_LINK_MODE_Pause_BIT, lpa);
        fs.asym_pause = test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT, lpa);

        val = swphy_read_reg(reg, &fs);
        if (reg == MII_BMSR) {
                if (!state->an_complete)
                        val &= ~BMSR_ANEGCOMPLETE;
        }
        return val;
}

static int phylink_phy_read(struct phylink *pl, unsigned int phy_id,
                            unsigned int reg)
{
        struct phy_device *phydev = pl->phydev;
        int prtad, devad;

        if (mdio_phy_id_is_c45(phy_id)) {
                prtad = mdio_phy_id_prtad(phy_id);
                devad = mdio_phy_id_devad(phy_id);
                devad = mdiobus_c45_addr(devad, reg);
        } else if (phydev->is_c45) {
                switch (reg) {
                case MII_BMCR:
                case MII_BMSR:
                case MII_PHYSID1:
                case MII_PHYSID2:
                        devad = __ffs(phydev->c45_ids.mmds_present);
                        break;
                case MII_ADVERTISE:
                case MII_LPA:
                        if (!(phydev->c45_ids.mmds_present & MDIO_DEVS_AN))
                                return -EINVAL;
                        devad = MDIO_MMD_AN;
                        if (reg == MII_ADVERTISE)
                                reg = MDIO_AN_ADVERTISE;
                        else
                                reg = MDIO_AN_LPA;
                        break;
                default:
                        return -EINVAL;
                }
                prtad = phy_id;
                devad = mdiobus_c45_addr(devad, reg);
        } else {
                prtad = phy_id;
                devad = reg;
        }
        return mdiobus_read(pl->phydev->mdio.bus, prtad, devad);
}

static int phylink_phy_write(struct phylink *pl, unsigned int phy_id,
                             unsigned int reg, unsigned int val)
{
        struct phy_device *phydev = pl->phydev;
        int prtad, devad;

        if (mdio_phy_id_is_c45(phy_id)) {
                prtad = mdio_phy_id_prtad(phy_id);
                devad = mdio_phy_id_devad(phy_id);
                devad = mdiobus_c45_addr(devad, reg);
        } else if (phydev->is_c45) {
                switch (reg) {
                case MII_BMCR:
                case MII_BMSR:
                case MII_PHYSID1:
                case MII_PHYSID2:
                        devad = __ffs(phydev->c45_ids.mmds_present);
                        break;
                case MII_ADVERTISE:
                case MII_LPA:
                        if (!(phydev->c45_ids.mmds_present & MDIO_DEVS_AN))
                                return -EINVAL;
                        devad = MDIO_MMD_AN;
                        if (reg == MII_ADVERTISE)
                                reg = MDIO_AN_ADVERTISE;
                        else
                                reg = MDIO_AN_LPA;
                        break;
                default:
                        return -EINVAL;
                }
                prtad = phy_id;
                devad = mdiobus_c45_addr(devad, reg);
        } else {
                prtad = phy_id;
                devad = reg;
        }

        return mdiobus_write(phydev->mdio.bus, prtad, devad, val);
}

static int phylink_mii_read(struct phylink *pl, unsigned int phy_id,
                            unsigned int reg)
{
        struct phylink_link_state state;
        int val = 0xffff;

        switch (pl->cur_link_an_mode) {
        case MLO_AN_FIXED:
                if (phy_id == 0) {
                        phylink_get_fixed_state(pl, &state);
                        val = phylink_mii_emul_read(reg, &state);
                }
                break;

        case MLO_AN_PHY:
                return -EOPNOTSUPP;

        case MLO_AN_INBAND:
                if (phy_id == 0) {
                        phylink_mac_pcs_get_state(pl, &state);
                        val = phylink_mii_emul_read(reg, &state);
                }
                break;
        }

        return val & 0xffff;

}

static int phylink_mii_write(struct phylink *pl, unsigned int phy_id,
                             unsigned int reg, unsigned int val)
{
        switch (pl->cur_link_an_mode) {
        case MLO_AN_FIXED:
                break;

        case MLO_AN_PHY:
                return -EOPNOTSUPP;

        case MLO_AN_INBAND:
                break;
        }

        return 0;
}

/**
 * phylink_mii_ioctl() - generic mii ioctl interface
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @ifr: a pointer to a &struct ifreq for socket ioctls
 * @cmd: ioctl cmd to execute
 *
 * Perform the specified MII ioctl on the PHY attached to the phylink instance
 * specified by @pl. If no PHY is attached, emulate the presence of the PHY.
 *
 * Returns: zero on success or negative error code.
 *
 * %SIOCGMIIPHY:
 *  read register from the current PHY.
 * %SIOCGMIIREG:
 *  read register from the specified PHY.
 * %SIOCSMIIREG:
 *  set a register on the specified PHY.
 */
int phylink_mii_ioctl(struct phylink *pl, struct ifreq *ifr, int cmd)
{
        struct mii_ioctl_data *mii = if_mii(ifr);
        int  ret;

        ASSERT_RTNL();

        if (pl->phydev) {
                /* PHYs only exist for MLO_AN_PHY and SGMII */
                switch (cmd) {
                case SIOCGMIIPHY:
                        mii->phy_id = pl->phydev->mdio.addr;
                        fallthrough;

                case SIOCGMIIREG:
                        ret = phylink_phy_read(pl, mii->phy_id, mii->reg_num);
                        if (ret >= 0) {
                                mii->val_out = ret;
                                ret = 0;
                        }
                        break;

                case SIOCSMIIREG:
                        ret = phylink_phy_write(pl, mii->phy_id, mii->reg_num,
                                                mii->val_in);
                        break;

                default:
                        ret = phy_mii_ioctl(pl->phydev, ifr, cmd);
                        break;
                }
        } else {
                switch (cmd) {
                case SIOCGMIIPHY:
                        mii->phy_id = 0;
                        fallthrough;

                case SIOCGMIIREG:
                        ret = phylink_mii_read(pl, mii->phy_id, mii->reg_num);
                        if (ret >= 0) {
                                mii->val_out = ret;
                                ret = 0;
                        }
                        break;

                case SIOCSMIIREG:
                        ret = phylink_mii_write(pl, mii->phy_id, mii->reg_num,
                                                mii->val_in);
                        break;

                default:
                        ret = -EOPNOTSUPP;
                        break;
                }
        }

        return ret;
}
EXPORT_SYMBOL_GPL(phylink_mii_ioctl);

/**
 * phylink_speed_down() - set the non-SFP PHY to lowest speed supported by both
 *   link partners
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 * @sync: perform action synchronously
 *
 * If we have a PHY that is not part of a SFP module, then set the speed
 * as described in the phy_speed_down() function. Please see this function
 * for a description of the @sync parameter.
 *
 * Returns zero if there is no PHY, otherwise as per phy_speed_down().
 */
int phylink_speed_down(struct phylink *pl, bool sync)
{
        int ret = 0;

        ASSERT_RTNL();

        if (!pl->sfp_bus && pl->phydev)
                ret = phy_speed_down(pl->phydev, sync);

        return ret;
}
EXPORT_SYMBOL_GPL(phylink_speed_down);

/**
 * phylink_speed_up() - restore the advertised speeds prior to the call to
 *   phylink_speed_down()
 * @pl: a pointer to a &struct phylink returned from phylink_create()
 *
 * If we have a PHY that is not part of a SFP module, then restore the
 * PHY speeds as per phy_speed_up().
 *
 * Returns zero if there is no PHY, otherwise as per phy_speed_up().
 */
int phylink_speed_up(struct phylink *pl)
{
        int ret = 0;

        ASSERT_RTNL();

        if (!pl->sfp_bus && pl->phydev)
                ret = phy_speed_up(pl->phydev);

        return ret;
}
EXPORT_SYMBOL_GPL(phylink_speed_up);

static void phylink_sfp_attach(void *upstream, struct sfp_bus *bus)
{
        struct phylink *pl = upstream;

        pl->netdev->sfp_bus = bus;
}

static void phylink_sfp_detach(void *upstream, struct sfp_bus *bus)
{
        struct phylink *pl = upstream;

        pl->netdev->sfp_bus = NULL;
}

static int phylink_sfp_config(struct phylink *pl, u8 mode,
                              const unsigned long *supported,
                              const unsigned long *advertising)
{
        __ETHTOOL_DECLARE_LINK_MODE_MASK(support1);
        __ETHTOOL_DECLARE_LINK_MODE_MASK(support);
        struct phylink_link_state config;
        phy_interface_t iface;
        bool changed;
        int ret;

        linkmode_copy(support, supported);

        memset(&config, 0, sizeof(config));
        linkmode_copy(config.advertising, advertising);
        config.interface = PHY_INTERFACE_MODE_NA;
        config.speed = SPEED_UNKNOWN;
        config.duplex = DUPLEX_UNKNOWN;
        config.pause = MLO_PAUSE_AN;
        config.an_enabled = pl->link_config.an_enabled;

        /* Ignore errors if we're expecting a PHY to attach later */
        ret = phylink_validate(pl, support, &config);
        if (ret) {
                phylink_err(pl, "validation with support %*pb failed: %d\n",
                            __ETHTOOL_LINK_MODE_MASK_NBITS, support, ret);
                return ret;
        }

        iface = sfp_select_interface(pl->sfp_bus, config.advertising);
        if (iface == PHY_INTERFACE_MODE_NA) {
                phylink_err(pl,
                            "selection of interface failed, advertisement %*pb\n",
                            __ETHTOOL_LINK_MODE_MASK_NBITS, config.advertising);
                return -EINVAL;
        }

        config.interface = iface;
        linkmode_copy(support1, support);
        ret = phylink_validate(pl, support1, &config);
        if (ret) {
                phylink_err(pl, "validation of %s/%s with support %*pb failed: %d\n",
                            phylink_an_mode_str(mode),
                            phy_modes(config.interface),
                            __ETHTOOL_LINK_MODE_MASK_NBITS, support, ret);
                return ret;
        }

        phylink_dbg(pl, "requesting link mode %s/%s with support %*pb\n",
                    phylink_an_mode_str(mode), phy_modes(config.interface),
                    __ETHTOOL_LINK_MODE_MASK_NBITS, support);

        if (phy_interface_mode_is_8023z(iface) && pl->phydev)
                return -EINVAL;

        changed = !linkmode_equal(pl->supported, support) ||
                  !linkmode_equal(pl->link_config.advertising,
                                  config.advertising);
        if (changed) {
                linkmode_copy(pl->supported, support);
                linkmode_copy(pl->link_config.advertising, config.advertising);
        }

        if (pl->cur_link_an_mode != mode ||
            pl->link_config.interface != config.interface) {
                pl->link_config.interface = config.interface;
                pl->cur_link_an_mode = mode;

                changed = true;

                phylink_info(pl, "switched to %s/%s link mode\n",
                             phylink_an_mode_str(mode),
                             phy_modes(config.interface));
        }

        pl->link_port = pl->sfp_port;

        if (changed && !test_bit(PHYLINK_DISABLE_STOPPED,
                                 &pl->phylink_disable_state))
                phylink_mac_initial_config(pl, false);

        return ret;
}

static int phylink_sfp_module_insert(void *upstream,
                                     const struct sfp_eeprom_id *id)
{
        struct phylink *pl = upstream;
        unsigned long *support = pl->sfp_support;

        ASSERT_RTNL();

        linkmode_zero(support);
        sfp_parse_support(pl->sfp_bus, id, support);
        pl->sfp_port = sfp_parse_port(pl->sfp_bus, id, support);

        /* If this module may have a PHY connecting later, defer until later */
        pl->sfp_may_have_phy = sfp_may_have_phy(pl->sfp_bus, id);
        if (pl->sfp_may_have_phy)
                return 0;

        return phylink_sfp_config(pl, MLO_AN_INBAND, support, support);
}

static int phylink_sfp_module_start(void *upstream)
{
        struct phylink *pl = upstream;

        /* If this SFP module has a PHY, start the PHY now. */
        if (pl->phydev) {
                phy_start(pl->phydev);
                return 0;
        }

        /* If the module may have a PHY but we didn't detect one we
         * need to configure the MAC here.
         */
        if (!pl->sfp_may_have_phy)
                return 0;

        return phylink_sfp_config(pl, MLO_AN_INBAND,
                                  pl->sfp_support, pl->sfp_support);
}

static void phylink_sfp_module_stop(void *upstream)
{
        struct phylink *pl = upstream;

        /* If this SFP module has a PHY, stop it. */
        if (pl->phydev)
                phy_stop(pl->phydev);
}

static void phylink_sfp_link_down(void *upstream)
{
        struct phylink *pl = upstream;

        ASSERT_RTNL();

        phylink_run_resolve_and_disable(pl, PHYLINK_DISABLE_LINK);
}

static void phylink_sfp_link_up(void *upstream)
{
        struct phylink *pl = upstream;

        ASSERT_RTNL();

        clear_bit(PHYLINK_DISABLE_LINK, &pl->phylink_disable_state);
        phylink_run_resolve(pl);
}

/* The Broadcom BCM84881 in the Methode DM7052 is unable to provide a SGMII
 * or 802.3z control word, so inband will not work.
 */
static bool phylink_phy_no_inband(struct phy_device *phy)
{
        return phy->is_c45 &&
                (phy->c45_ids.device_ids[1] & 0xfffffff0) == 0xae025150;
}

static int phylink_sfp_connect_phy(void *upstream, struct phy_device *phy)
{
        struct phylink *pl = upstream;
        phy_interface_t interface;
        u8 mode;
        int ret;

        /*
         * This is the new way of dealing with flow control for PHYs,
         * as described by Timur Tabi in commit 529ed1275263 ("net: phy:
         * phy drivers should not set SUPPORTED_[Asym_]Pause") except
         * using our validate call to the MAC, we rely upon the MAC
         * clearing the bits from both supported and advertising fields.
         */
        phy_support_asym_pause(phy);

        if (phylink_phy_no_inband(phy))
                mode = MLO_AN_PHY;
        else
                mode = MLO_AN_INBAND;

        /* Do the initial configuration */
        ret = phylink_sfp_config(pl, mode, phy->supported, phy->advertising);
        if (ret < 0)
                return ret;

        interface = pl->link_config.interface;
        ret = phylink_attach_phy(pl, phy, interface);
        if (ret < 0)
                return ret;

        ret = phylink_bringup_phy(pl, phy, interface);
        if (ret)
                phy_detach(phy);

        return ret;
}

static void phylink_sfp_disconnect_phy(void *upstream)
{
        phylink_disconnect_phy(upstream);
}

static const struct sfp_upstream_ops sfp_phylink_ops = {
        .attach = phylink_sfp_attach,
        .detach = phylink_sfp_detach,
        .module_insert = phylink_sfp_module_insert,
        .module_start = phylink_sfp_module_start,
        .module_stop = phylink_sfp_module_stop,
        .link_up = phylink_sfp_link_up,
        .link_down = phylink_sfp_link_down,
        .connect_phy = phylink_sfp_connect_phy,
        .disconnect_phy = phylink_sfp_disconnect_phy,
};

/* Helpers for MAC drivers */

/**
 * phylink_helper_basex_speed() - 1000BaseX/2500BaseX helper
 * @state: a pointer to a &struct phylink_link_state
 *
 * Inspect the interface mode, advertising mask or forced speed and
 * decide whether to run at 2.5Gbit or 1Gbit appropriately, switching
 * the interface mode to suit.  @state->interface is appropriately
 * updated, and the advertising mask has the "other" baseX_Full flag
 * cleared.
 */
void phylink_helper_basex_speed(struct phylink_link_state *state)
{
        if (phy_interface_mode_is_8023z(state->interface)) {
                bool want_2500 = state->an_enabled ?
                        phylink_test(state->advertising, 2500baseX_Full) :
                        state->speed == SPEED_2500;

                if (want_2500) {
                        phylink_clear(state->advertising, 1000baseX_Full);
                        state->interface = PHY_INTERFACE_MODE_2500BASEX;
                } else {
                        phylink_clear(state->advertising, 2500baseX_Full);
                        state->interface = PHY_INTERFACE_MODE_1000BASEX;
                }
        }
}
EXPORT_SYMBOL_GPL(phylink_helper_basex_speed);

static void phylink_decode_c37_word(struct phylink_link_state *state,
                                    uint16_t config_reg, int speed)
{
        bool tx_pause, rx_pause;
        int fd_bit;

        if (speed == SPEED_2500)
                fd_bit = ETHTOOL_LINK_MODE_2500baseX_Full_BIT;
        else
                fd_bit = ETHTOOL_LINK_MODE_1000baseX_Full_BIT;

        mii_lpa_mod_linkmode_x(state->lp_advertising, config_reg, fd_bit);

        if (linkmode_test_bit(fd_bit, state->advertising) &&
            linkmode_test_bit(fd_bit, state->lp_advertising)) {
                state->speed = speed;
                state->duplex = DUPLEX_FULL;
        } else {
                /* negotiation failure */
                state->link = false;
        }

        linkmode_resolve_pause(state->advertising, state->lp_advertising,
                               &tx_pause, &rx_pause);

        if (tx_pause)
                state->pause |= MLO_PAUSE_TX;
        if (rx_pause)
                state->pause |= MLO_PAUSE_RX;
}

static void phylink_decode_sgmii_word(struct phylink_link_state *state,
                                      uint16_t config_reg)
{
        if (!(config_reg & LPA_SGMII_LINK)) {
                state->link = false;
                return;
        }

        switch (config_reg & LPA_SGMII_SPD_MASK) {
        case LPA_SGMII_10:
                state->speed = SPEED_10;
                break;
        case LPA_SGMII_100:
                state->speed = SPEED_100;
                break;
        case LPA_SGMII_1000:
                state->speed = SPEED_1000;
                break;
        default:
                state->link = false;
                return;
        }
        if (config_reg & LPA_SGMII_FULL_DUPLEX)
                state->duplex = DUPLEX_FULL;
        else
                state->duplex = DUPLEX_HALF;
}

/**
 * phylink_decode_usxgmii_word() - decode the USXGMII word from a MAC PCS
 * @state: a pointer to a struct phylink_link_state.
 * @lpa: a 16 bit value which stores the USXGMII auto-negotiation word
 *
 * Helper for MAC PCS supporting the USXGMII protocol and the auto-negotiation
 * code word.  Decode the USXGMII code word and populate the corresponding fields
 * (speed, duplex) into the phylink_link_state structure.
 */
void phylink_decode_usxgmii_word(struct phylink_link_state *state,
                                 uint16_t lpa)
{
        switch (lpa & MDIO_USXGMII_SPD_MASK) {
        case MDIO_USXGMII_10:
                state->speed = SPEED_10;
                break;
        case MDIO_USXGMII_100:
                state->speed = SPEED_100;
                break;
        case MDIO_USXGMII_1000:
                state->speed = SPEED_1000;
                break;
        case MDIO_USXGMII_2500:
                state->speed = SPEED_2500;
                break;
        case MDIO_USXGMII_5000:
                state->speed = SPEED_5000;
                break;
        case MDIO_USXGMII_10G:
                state->speed = SPEED_10000;
                break;
        default:
                state->link = false;
                return;
        }

        if (lpa & MDIO_USXGMII_FULL_DUPLEX)
                state->duplex = DUPLEX_FULL;
        else
                state->duplex = DUPLEX_HALF;
}
EXPORT_SYMBOL_GPL(phylink_decode_usxgmii_word);

/**
 * phylink_mii_c22_pcs_get_state() - read the MAC PCS state
 * @pcs: a pointer to a &struct mdio_device.
 * @state: a pointer to a &struct phylink_link_state.
 *
 * Helper for MAC PCS supporting the 802.3 clause 22 register set for
 * clause 37 negotiation and/or SGMII control.
 *
 * Read the MAC PCS state from the MII device configured in @config and
 * parse the Clause 37 or Cisco SGMII link partner negotiation word into
 * the phylink @state structure. This is suitable to be directly plugged
 * into the mac_pcs_get_state() member of the struct phylink_mac_ops
 * structure.
 */
void phylink_mii_c22_pcs_get_state(struct mdio_device *pcs,
                                   struct phylink_link_state *state)
{
        struct mii_bus *bus = pcs->bus;
        int addr = pcs->addr;
        int bmsr, lpa;

        bmsr = mdiobus_read(bus, addr, MII_BMSR);
        lpa = mdiobus_read(bus, addr, MII_LPA);
        if (bmsr < 0 || lpa < 0) {
                state->link = false;
                return;
        }

        state->link = !!(bmsr & BMSR_LSTATUS);
        state->an_complete = !!(bmsr & BMSR_ANEGCOMPLETE);
        if (!state->link)
                return;

        switch (state->interface) {
        case PHY_INTERFACE_MODE_1000BASEX:
                phylink_decode_c37_word(state, lpa, SPEED_1000);
                break;

        case PHY_INTERFACE_MODE_2500BASEX:
                phylink_decode_c37_word(state, lpa, SPEED_2500);
                break;

        case PHY_INTERFACE_MODE_SGMII:
        case PHY_INTERFACE_MODE_QSGMII:
                phylink_decode_sgmii_word(state, lpa);
                break;

        default:
                state->link = false;
                break;
        }
}
EXPORT_SYMBOL_GPL(phylink_mii_c22_pcs_get_state);

/**
 * phylink_mii_c22_pcs_set_advertisement() - configure the clause 37 PCS
 *      advertisement
 * @pcs: a pointer to a &struct mdio_device.
 * @interface: the PHY interface mode being configured
 * @advertising: the ethtool advertisement mask
 *
 * Helper for MAC PCS supporting the 802.3 clause 22 register set for
 * clause 37 negotiation and/or SGMII control.
 *
 * Configure the clause 37 PCS advertisement as specified by @state. This
 * does not trigger a renegotiation; phylink will do that via the
 * mac_an_restart() method of the struct phylink_mac_ops structure.
 *
 * Returns negative error code on failure to configure the advertisement,
 * zero if no change has been made, or one if the advertisement has changed.
 */
int phylink_mii_c22_pcs_set_advertisement(struct mdio_device *pcs,
                                          phy_interface_t interface,
                                          const unsigned long *advertising)
{
        struct mii_bus *bus = pcs->bus;
        int addr = pcs->addr;
        int val, ret;
        u16 adv;

        switch (interface) {
        case PHY_INTERFACE_MODE_1000BASEX:
        case PHY_INTERFACE_MODE_2500BASEX:
                adv = ADVERTISE_1000XFULL;
                if (linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT,
                                      advertising))
                        adv |= ADVERTISE_1000XPAUSE;
                if (linkmode_test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
                                      advertising))
                        adv |= ADVERTISE_1000XPSE_ASYM;

                val = mdiobus_read(bus, addr, MII_ADVERTISE);
                if (val < 0)
                        return val;

                if (val == adv)
                        return 0;

                ret = mdiobus_write(bus, addr, MII_ADVERTISE, adv);
                if (ret < 0)
                        return ret;

                return 1;

        case PHY_INTERFACE_MODE_SGMII:
                val = mdiobus_read(bus, addr, MII_ADVERTISE);
                if (val < 0)
                        return val;

                if (val == 0x0001)
                        return 0;

                ret = mdiobus_write(bus, addr, MII_ADVERTISE, 0x0001);
                if (ret < 0)
                        return ret;

                return 1;

        default:
                /* Nothing to do for other modes */
                return 0;
        }
}
EXPORT_SYMBOL_GPL(phylink_mii_c22_pcs_set_advertisement);

/**
 * phylink_mii_c22_pcs_config() - configure clause 22 PCS
 * @pcs: a pointer to a &struct mdio_device.
 * @mode: link autonegotiation mode
 * @interface: the PHY interface mode being configured
 * @advertising: the ethtool advertisement mask
 *
 * Configure a Clause 22 PCS PHY with the appropriate negotiation
 * parameters for the @mode, @interface and @advertising parameters.
 * Returns negative error number on failure, zero if the advertisement
 * has not changed, or positive if there is a change.
 */
int phylink_mii_c22_pcs_config(struct mdio_device *pcs, unsigned int mode,
                               phy_interface_t interface,
                               const unsigned long *advertising)
{
        bool changed;
        u16 bmcr;
        int ret;

        ret = phylink_mii_c22_pcs_set_advertisement(pcs, interface,
                                                    advertising);
        if (ret < 0)
                return ret;

        changed = ret > 0;

        /* Ensure ISOLATE bit is disabled */
        bmcr = mode == MLO_AN_INBAND ? BMCR_ANENABLE : 0;
        ret = mdiobus_modify(pcs->bus, pcs->addr, MII_BMCR,
                             BMCR_ANENABLE | BMCR_ISOLATE, bmcr);
        if (ret < 0)
                return ret;

        return changed ? 1 : 0;
}
EXPORT_SYMBOL_GPL(phylink_mii_c22_pcs_config);

/**
 * phylink_mii_c22_pcs_an_restart() - restart 802.3z autonegotiation
 * @pcs: a pointer to a &struct mdio_device.
 *
 * Helper for MAC PCS supporting the 802.3 clause 22 register set for
 * clause 37 negotiation.
 *
 * Restart the clause 37 negotiation with the link partner. This is
 * suitable to be directly plugged into the mac_pcs_get_state() member
 * of the struct phylink_mac_ops structure.
 */
void phylink_mii_c22_pcs_an_restart(struct mdio_device *pcs)
{
        struct mii_bus *bus = pcs->bus;
        int val, addr = pcs->addr;

        val = mdiobus_read(bus, addr, MII_BMCR);
        if (val >= 0) {
                val |= BMCR_ANRESTART;

                mdiobus_write(bus, addr, MII_BMCR, val);
        }
}
EXPORT_SYMBOL_GPL(phylink_mii_c22_pcs_an_restart);

void phylink_mii_c45_pcs_get_state(struct mdio_device *pcs,
                                   struct phylink_link_state *state)
{
        struct mii_bus *bus = pcs->bus;
        int addr = pcs->addr;
        int stat;

        stat = mdiobus_c45_read(bus, addr, MDIO_MMD_PCS, MDIO_STAT1);
        if (stat < 0) {
                state->link = false;
                return;
        }

        state->link = !!(stat & MDIO_STAT1_LSTATUS);
        if (!state->link)
                return;

        switch (state->interface) {
        case PHY_INTERFACE_MODE_10GBASER:
                state->speed = SPEED_10000;
                state->duplex = DUPLEX_FULL;
                break;

        default:
                break;
        }
}
EXPORT_SYMBOL_GPL(phylink_mii_c45_pcs_get_state);

MODULE_LICENSE("GPL v2");