root/drivers/net/phy/adin1100.c
// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
/*
 *  Driver for Analog Devices Industrial Ethernet T1L PHYs
 *
 * Copyright 2020 Analog Devices Inc.
 */
#include <linux/kernel.h>
#include <linux/bitfield.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mii.h>
#include <linux/phy.h>
#include <linux/property.h>

#define PHY_ID_ADIN1100                         0x0283bc81
#define PHY_ID_ADIN1110                         0x0283bc91
#define PHY_ID_ADIN2111                         0x0283bca1

#define ADIN_PHY_SUBSYS_IRQ_MASK                0x0021
#define   ADIN_LINK_STAT_CHNG_IRQ_EN            BIT(1)

#define ADIN_PHY_SUBSYS_IRQ_STATUS              0x0011
#define   ADIN_LINK_STAT_CHNG                   BIT(1)

#define ADIN_FORCED_MODE                        0x8000
#define   ADIN_FORCED_MODE_EN                   BIT(0)

#define ADIN_CRSM_SFT_RST                       0x8810
#define   ADIN_CRSM_SFT_RST_EN                  BIT(0)

#define ADIN_CRSM_SFT_PD_CNTRL                  0x8812
#define   ADIN_CRSM_SFT_PD_CNTRL_EN             BIT(0)

#define ADIN_AN_PHY_INST_STATUS                 0x8030
#define   ADIN_IS_CFG_SLV                       BIT(2)
#define   ADIN_IS_CFG_MST                       BIT(3)

#define ADIN_CRSM_STAT                          0x8818
#define   ADIN_CRSM_SFT_PD_RDY                  BIT(1)
#define   ADIN_CRSM_SYS_RDY                     BIT(0)

#define ADIN_MSE_VAL                            0x830B

#define ADIN_SQI_MAX    7

struct adin_mse_sqi_range {
        u16 start;
        u16 end;
};

static const struct adin_mse_sqi_range adin_mse_sqi_map[] = {
        { 0x0A74, 0xFFFF },
        { 0x084E, 0x0A74 },
        { 0x0698, 0x084E },
        { 0x053D, 0x0698 },
        { 0x0429, 0x053D },
        { 0x034E, 0x0429 },
        { 0x02A0, 0x034E },
        { 0x0000, 0x02A0 },
};

/**
 * struct adin_priv - ADIN PHY driver private data
 * @tx_level_2v4_able:          set if the PHY supports 2.4V TX levels (10BASE-T1L)
 * @tx_level_2v4:               set if the PHY requests 2.4V TX levels (10BASE-T1L)
 * @tx_level_prop_present:      set if the TX level is specified in DT
 */
struct adin_priv {
        unsigned int            tx_level_2v4_able:1;
        unsigned int            tx_level_2v4:1;
        unsigned int            tx_level_prop_present:1;
};

static int adin_read_status(struct phy_device *phydev)
{
        int ret;

        ret = genphy_c45_read_status(phydev);
        if (ret)
                return ret;

        ret = phy_read_mmd(phydev, MDIO_MMD_AN, ADIN_AN_PHY_INST_STATUS);
        if (ret < 0)
                return ret;

        if (ret & ADIN_IS_CFG_SLV)
                phydev->master_slave_state = MASTER_SLAVE_STATE_SLAVE;

        if (ret & ADIN_IS_CFG_MST)
                phydev->master_slave_state = MASTER_SLAVE_STATE_MASTER;

        return 0;
}

static int adin_config_aneg(struct phy_device *phydev)
{
        struct adin_priv *priv = phydev->priv;
        int ret;

        if (phydev->autoneg == AUTONEG_DISABLE) {
                ret = genphy_c45_pma_setup_forced(phydev);
                if (ret < 0)
                        return ret;

                if (priv->tx_level_prop_present && priv->tx_level_2v4)
                        ret = phy_set_bits_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_B10L_PMA_CTRL,
                                               MDIO_PMA_10T1L_CTRL_2V4_EN);
                else
                        ret = phy_clear_bits_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_B10L_PMA_CTRL,
                                                 MDIO_PMA_10T1L_CTRL_2V4_EN);
                if (ret < 0)
                        return ret;

                /* Force PHY to use above configurations */
                return phy_set_bits_mmd(phydev, MDIO_MMD_AN, ADIN_FORCED_MODE, ADIN_FORCED_MODE_EN);
        }

        ret = phy_clear_bits_mmd(phydev, MDIO_MMD_AN, ADIN_FORCED_MODE, ADIN_FORCED_MODE_EN);
        if (ret < 0)
                return ret;

        /* Request increased transmit level from LP. */
        if (priv->tx_level_prop_present && priv->tx_level_2v4) {
                ret = phy_set_bits_mmd(phydev, MDIO_MMD_AN, MDIO_AN_T1_ADV_H,
                                       MDIO_AN_T1_ADV_H_10L_TX_HI |
                                       MDIO_AN_T1_ADV_H_10L_TX_HI_REQ);
                if (ret < 0)
                        return ret;
        }

        /* Disable 2.4 Vpp transmit level. */
        if ((priv->tx_level_prop_present && !priv->tx_level_2v4) || !priv->tx_level_2v4_able) {
                ret = phy_clear_bits_mmd(phydev, MDIO_MMD_AN, MDIO_AN_T1_ADV_H,
                                         MDIO_AN_T1_ADV_H_10L_TX_HI |
                                         MDIO_AN_T1_ADV_H_10L_TX_HI_REQ);
                if (ret < 0)
                        return ret;
        }

        return genphy_c45_config_aneg(phydev);
}

static int adin_phy_ack_intr(struct phy_device *phydev)
{
        /* Clear pending interrupts */
        int rc = phy_read_mmd(phydev, MDIO_MMD_VEND2,
                              ADIN_PHY_SUBSYS_IRQ_STATUS);

        return rc < 0 ? rc : 0;
}

static int adin_config_intr(struct phy_device *phydev)
{
        u16 irq_mask;
        int ret;

        ret = adin_phy_ack_intr(phydev);
        if (ret)
                return ret;

        if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
                irq_mask = ADIN_LINK_STAT_CHNG_IRQ_EN;
        else
                irq_mask = 0;

        return phy_modify_mmd(phydev, MDIO_MMD_VEND2,
                              ADIN_PHY_SUBSYS_IRQ_MASK,
                              ADIN_LINK_STAT_CHNG_IRQ_EN, irq_mask);
}

static irqreturn_t adin_phy_handle_interrupt(struct phy_device *phydev)
{
        int irq_status;

        irq_status = phy_read_mmd(phydev, MDIO_MMD_VEND2,
                                  ADIN_PHY_SUBSYS_IRQ_STATUS);
        if (irq_status < 0) {
                phy_error(phydev);
                return IRQ_NONE;
        }

        if (!(irq_status & ADIN_LINK_STAT_CHNG))
                return IRQ_NONE;

        phy_trigger_machine(phydev);

        return IRQ_HANDLED;
}

static int adin_set_powerdown_mode(struct phy_device *phydev, bool en)
{
        int ret;

        ret = phy_write_mmd(phydev, MDIO_MMD_VEND1,
                            ADIN_CRSM_SFT_PD_CNTRL,
                            en ? ADIN_CRSM_SFT_PD_CNTRL_EN : 0);
        if (ret < 0)
                return ret;

        return phy_read_mmd_poll_timeout(phydev, MDIO_MMD_VEND1, ADIN_CRSM_STAT, ret,
                                         !!(ret & ADIN_CRSM_SFT_PD_RDY) == en,
                                         1000, 30000, true);
}

static int adin_suspend(struct phy_device *phydev)
{
        return adin_set_powerdown_mode(phydev, true);
}

static int adin_resume(struct phy_device *phydev)
{
        return adin_set_powerdown_mode(phydev, false);
}

static int adin_set_loopback(struct phy_device *phydev, bool enable, int speed)
{
        if (enable && speed)
                return -EOPNOTSUPP;

        if (enable)
                return phy_set_bits_mmd(phydev, MDIO_MMD_PCS, MDIO_PCS_10T1L_CTRL,
                                        BMCR_LOOPBACK);

        /* PCS loopback (according to 10BASE-T1L spec) */
        return phy_clear_bits_mmd(phydev, MDIO_MMD_PCS, MDIO_PCS_10T1L_CTRL,
                                 BMCR_LOOPBACK);
}

static int adin_soft_reset(struct phy_device *phydev)
{
        int ret;

        ret = phy_set_bits_mmd(phydev, MDIO_MMD_VEND1, ADIN_CRSM_SFT_RST, ADIN_CRSM_SFT_RST_EN);
        if (ret < 0)
                return ret;

        return phy_read_mmd_poll_timeout(phydev, MDIO_MMD_VEND1, ADIN_CRSM_STAT, ret,
                                         (ret & ADIN_CRSM_SYS_RDY),
                                         10000, 30000, true);
}

static int adin_get_features(struct phy_device *phydev)
{
        struct adin_priv *priv = phydev->priv;
        struct device *dev = &phydev->mdio.dev;
        int ret;
        u8 val;

        ret = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_PMA_10T1L_STAT);
        if (ret < 0)
                return ret;

        /* This depends on the voltage level from the power source */
        priv->tx_level_2v4_able = !!(ret & MDIO_PMA_10T1L_STAT_2V4_ABLE);

        phydev_dbg(phydev, "PHY supports 2.4V TX level: %s\n",
                   priv->tx_level_2v4_able ? "yes" : "no");

        priv->tx_level_prop_present = device_property_present(dev, "phy-10base-t1l-2.4vpp");
        if (priv->tx_level_prop_present) {
                ret = device_property_read_u8(dev, "phy-10base-t1l-2.4vpp", &val);
                if (ret < 0)
                        return ret;

                priv->tx_level_2v4 = val;
                if (!priv->tx_level_2v4 && priv->tx_level_2v4_able)
                        phydev_info(phydev,
                                    "PHY supports 2.4V TX level, but disabled via config\n");
        }

        linkmode_set_bit_array(phy_basic_ports_array, ARRAY_SIZE(phy_basic_ports_array),
                               phydev->supported);

        return genphy_c45_pma_read_abilities(phydev);
}

static int adin_get_sqi(struct phy_device *phydev)
{
        u16 mse_val;
        int sqi;
        int ret;

        ret = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_STAT1);
        if (ret < 0)
                return ret;
        else if (!(ret & MDIO_STAT1_LSTATUS))
                return 0;

        ret = phy_read_mmd(phydev, MDIO_STAT1, ADIN_MSE_VAL);
        if (ret < 0)
                return ret;

        mse_val = 0xFFFF & ret;
        for (sqi = 0; sqi < ARRAY_SIZE(adin_mse_sqi_map); sqi++) {
                if (mse_val >= adin_mse_sqi_map[sqi].start && mse_val <= adin_mse_sqi_map[sqi].end)
                        return sqi;
        }

        return -EINVAL;
}

static int adin_get_sqi_max(struct phy_device *phydev)
{
        return ADIN_SQI_MAX;
}

static int adin_probe(struct phy_device *phydev)
{
        struct device *dev = &phydev->mdio.dev;
        struct adin_priv *priv;

        priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
        if (!priv)
                return -ENOMEM;

        phydev->priv = priv;

        return 0;
}

static struct phy_driver adin_driver[] = {
        {
                .phy_id                 = PHY_ID_ADIN1100,
                .phy_id_mask            = 0xffffffcf,
                .name                   = "ADIN1100",
                .get_features           = adin_get_features,
                .soft_reset             = adin_soft_reset,
                .probe                  = adin_probe,
                .config_aneg            = adin_config_aneg,
                .read_status            = adin_read_status,
                .config_intr            = adin_config_intr,
                .handle_interrupt       = adin_phy_handle_interrupt,
                .set_loopback           = adin_set_loopback,
                .suspend                = adin_suspend,
                .resume                 = adin_resume,
                .get_sqi                = adin_get_sqi,
                .get_sqi_max            = adin_get_sqi_max,
        },
};

module_phy_driver(adin_driver);

static const struct mdio_device_id __maybe_unused adin_tbl[] = {
        { PHY_ID_MATCH_MODEL(PHY_ID_ADIN1100) },
        { PHY_ID_MATCH_MODEL(PHY_ID_ADIN1110) },
        { PHY_ID_MATCH_MODEL(PHY_ID_ADIN2111) },
        { }
};

MODULE_DEVICE_TABLE(mdio, adin_tbl);
MODULE_DESCRIPTION("Analog Devices Industrial Ethernet T1L PHY driver");
MODULE_LICENSE("Dual BSD/GPL");