// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2017 Pengutronix, Juergen Borleis <kernel@pengutronix.de>
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/gpio/consumer.h>
#include <linux/regmap.h>
#include <linux/mutex.h>
#include <linux/mii.h>
#include <linux/phy.h>
#include <linux/if_bridge.h>
#include <linux/if_vlan.h>
#include <linux/etherdevice.h>

#include "lan9303.h"

#define LAN9303_NUM_PORTS 3

/* 13.2 System Control and Status Registers
 * Multiply register number by 4 to get address offset.
 */
#define LAN9303_CHIP_REV 0x14
# define LAN9303_CHIP_ID 0x9303
#define LAN9303_IRQ_CFG 0x15
# define LAN9303_IRQ_CFG_IRQ_ENABLE BIT(8)
# define LAN9303_IRQ_CFG_IRQ_POL BIT(4)
# define LAN9303_IRQ_CFG_IRQ_TYPE BIT(0)
#define LAN9303_INT_STS 0x16
# define LAN9303_INT_STS_PHY_INT2 BIT(27)
# define LAN9303_INT_STS_PHY_INT1 BIT(26)
#define LAN9303_INT_EN 0x17
# define LAN9303_INT_EN_PHY_INT2_EN BIT(27)
# define LAN9303_INT_EN_PHY_INT1_EN BIT(26)
#define LAN9303_HW_CFG 0x1D
# define LAN9303_HW_CFG_READY BIT(27)
# define LAN9303_HW_CFG_AMDX_EN_PORT2 BIT(26)
# define LAN9303_HW_CFG_AMDX_EN_PORT1 BIT(25)
#define LAN9303_PMI_DATA 0x29
#define LAN9303_PMI_ACCESS 0x2A
# define LAN9303_PMI_ACCESS_PHY_ADDR(x) (((x) & 0x1f) << 11)
# define LAN9303_PMI_ACCESS_MIIRINDA(x) (((x) & 0x1f) << 6)
# define LAN9303_PMI_ACCESS_MII_BUSY BIT(0)
# define LAN9303_PMI_ACCESS_MII_WRITE BIT(1)
#define LAN9303_MANUAL_FC_1 0x68
#define LAN9303_MANUAL_FC_2 0x69
#define LAN9303_MANUAL_FC_0 0x6a
#define LAN9303_SWITCH_CSR_DATA 0x6b
#define LAN9303_SWITCH_CSR_CMD 0x6c
#define LAN9303_SWITCH_CSR_CMD_BUSY BIT(31)
#define LAN9303_SWITCH_CSR_CMD_RW BIT(30)
#define LAN9303_SWITCH_CSR_CMD_LANES (BIT(19) | BIT(18) | BIT(17) | BIT(16))
#define LAN9303_VIRT_PHY_BASE 0x70
#define LAN9303_VIRT_SPECIAL_CTRL 0x77
#define  LAN9303_VIRT_SPECIAL_TURBO BIT(10) /*Turbo MII Enable*/

/*13.4 Switch Fabric Control and Status Registers
 * Accessed indirectly via SWITCH_CSR_CMD, SWITCH_CSR_DATA.
 */
#define LAN9303_SW_DEV_ID 0x0000
#define LAN9303_SW_RESET 0x0001
#define LAN9303_SW_RESET_RESET BIT(0)
#define LAN9303_SW_IMR 0x0004
#define LAN9303_SW_IPR 0x0005
#define LAN9303_MAC_VER_ID_0 0x0400
#define LAN9303_MAC_RX_CFG_0 0x0401
# define LAN9303_MAC_RX_CFG_X_REJECT_MAC_TYPES BIT(1)
# define LAN9303_MAC_RX_CFG_X_RX_ENABLE BIT(0)
#define LAN9303_MAC_RX_UNDSZE_CNT_0 0x0410
#define LAN9303_MAC_RX_64_CNT_0 0x0411
#define LAN9303_MAC_RX_127_CNT_0 0x0412
#define LAN9303_MAC_RX_255_CNT_0 0x413
#define LAN9303_MAC_RX_511_CNT_0 0x0414
#define LAN9303_MAC_RX_1023_CNT_0 0x0415
#define LAN9303_MAC_RX_MAX_CNT_0 0x0416
#define LAN9303_MAC_RX_OVRSZE_CNT_0 0x0417
#define LAN9303_MAC_RX_PKTOK_CNT_0 0x0418
#define LAN9303_MAC_RX_CRCERR_CNT_0 0x0419
#define LAN9303_MAC_RX_MULCST_CNT_0 0x041a
#define LAN9303_MAC_RX_BRDCST_CNT_0 0x041b
#define LAN9303_MAC_RX_PAUSE_CNT_0 0x041c
#define LAN9303_MAC_RX_FRAG_CNT_0 0x041d
#define LAN9303_MAC_RX_JABB_CNT_0 0x041e
#define LAN9303_MAC_RX_ALIGN_CNT_0 0x041f
#define LAN9303_MAC_RX_PKTLEN_CNT_0 0x0420
#define LAN9303_MAC_RX_GOODPKTLEN_CNT_0 0x0421
#define LAN9303_MAC_RX_SYMBL_CNT_0 0x0422
#define LAN9303_MAC_RX_CTLFRM_CNT_0 0x0423

#define LAN9303_MAC_TX_CFG_0 0x0440
# define LAN9303_MAC_TX_CFG_X_TX_IFG_CONFIG_DEFAULT (21 << 2)
# define LAN9303_MAC_TX_CFG_X_TX_PAD_ENABLE BIT(1)
# define LAN9303_MAC_TX_CFG_X_TX_ENABLE BIT(0)
#define LAN9303_MAC_TX_DEFER_CNT_0 0x0451
#define LAN9303_MAC_TX_PAUSE_CNT_0 0x0452
#define LAN9303_MAC_TX_PKTOK_CNT_0 0x0453
#define LAN9303_MAC_TX_64_CNT_0 0x0454
#define LAN9303_MAC_TX_127_CNT_0 0x0455
#define LAN9303_MAC_TX_255_CNT_0 0x0456
#define LAN9303_MAC_TX_511_CNT_0 0x0457
#define LAN9303_MAC_TX_1023_CNT_0 0x0458
#define LAN9303_MAC_TX_MAX_CNT_0 0x0459
#define LAN9303_MAC_TX_UNDSZE_CNT_0 0x045a
#define LAN9303_MAC_TX_PKTLEN_CNT_0 0x045c
#define LAN9303_MAC_TX_BRDCST_CNT_0 0x045d
#define LAN9303_MAC_TX_MULCST_CNT_0 0x045e
#define LAN9303_MAC_TX_LATECOL_0 0x045f
#define LAN9303_MAC_TX_EXCOL_CNT_0 0x0460
#define LAN9303_MAC_TX_SNGLECOL_CNT_0 0x0461
#define LAN9303_MAC_TX_MULTICOL_CNT_0 0x0462
#define LAN9303_MAC_TX_TOTALCOL_CNT_0 0x0463

#define LAN9303_MAC_VER_ID_1 0x0800
#define LAN9303_MAC_RX_CFG_1 0x0801
#define LAN9303_MAC_TX_CFG_1 0x0840
#define LAN9303_MAC_VER_ID_2 0x0c00
#define LAN9303_MAC_RX_CFG_2 0x0c01
#define LAN9303_MAC_TX_CFG_2 0x0c40
#define LAN9303_SWE_ALR_CMD 0x1800
# define LAN9303_ALR_CMD_MAKE_ENTRY    BIT(2)
# define LAN9303_ALR_CMD_GET_FIRST     BIT(1)
# define LAN9303_ALR_CMD_GET_NEXT      BIT(0)
#define LAN9303_SWE_ALR_WR_DAT_0 0x1801
#define LAN9303_SWE_ALR_WR_DAT_1 0x1802
# define LAN9303_ALR_DAT1_VALID        BIT(26)
# define LAN9303_ALR_DAT1_END_OF_TABL  BIT(25)
# define LAN9303_ALR_DAT1_AGE_OVERRID  BIT(25)
# define LAN9303_ALR_DAT1_STATIC       BIT(24)
# define LAN9303_ALR_DAT1_PORT_BITOFFS  16
# define LAN9303_ALR_DAT1_PORT_MASK    (7 << LAN9303_ALR_DAT1_PORT_BITOFFS)
#define LAN9303_SWE_ALR_RD_DAT_0 0x1805
#define LAN9303_SWE_ALR_RD_DAT_1 0x1806
#define LAN9303_SWE_ALR_CMD_STS 0x1808
# define ALR_STS_MAKE_PEND     BIT(0)
#define LAN9303_SWE_VLAN_CMD 0x180b
# define LAN9303_SWE_VLAN_CMD_RNW BIT(5)
# define LAN9303_SWE_VLAN_CMD_PVIDNVLAN BIT(4)
#define LAN9303_SWE_VLAN_WR_DATA 0x180c
#define LAN9303_SWE_VLAN_RD_DATA 0x180e
# define LAN9303_SWE_VLAN_MEMBER_PORT2 BIT(17)
# define LAN9303_SWE_VLAN_UNTAG_PORT2 BIT(16)
# define LAN9303_SWE_VLAN_MEMBER_PORT1 BIT(15)
# define LAN9303_SWE_VLAN_UNTAG_PORT1 BIT(14)
# define LAN9303_SWE_VLAN_MEMBER_PORT0 BIT(13)
# define LAN9303_SWE_VLAN_UNTAG_PORT0 BIT(12)
#define LAN9303_SWE_VLAN_CMD_STS 0x1810
#define LAN9303_SWE_GLB_INGRESS_CFG 0x1840
# define LAN9303_SWE_GLB_INGR_IGMP_TRAP BIT(7)
# define LAN9303_SWE_GLB_INGR_IGMP_PORT(p) BIT(10 + p)
#define LAN9303_SWE_PORT_STATE 0x1843
# define LAN9303_SWE_PORT_STATE_FORWARDING_PORT2 (0)
# define LAN9303_SWE_PORT_STATE_LEARNING_PORT2 BIT(5)
# define LAN9303_SWE_PORT_STATE_BLOCKING_PORT2 BIT(4)
# define LAN9303_SWE_PORT_STATE_FORWARDING_PORT1 (0)
# define LAN9303_SWE_PORT_STATE_LEARNING_PORT1 BIT(3)
# define LAN9303_SWE_PORT_STATE_BLOCKING_PORT1 BIT(2)
# define LAN9303_SWE_PORT_STATE_FORWARDING_PORT0 (0)
# define LAN9303_SWE_PORT_STATE_LEARNING_PORT0 BIT(1)
# define LAN9303_SWE_PORT_STATE_BLOCKING_PORT0 BIT(0)
# define LAN9303_SWE_PORT_STATE_DISABLED_PORT0 (3)
#define LAN9303_SWE_PORT_MIRROR 0x1846
# define LAN9303_SWE_PORT_MIRROR_SNIFF_ALL BIT(8)
# define LAN9303_SWE_PORT_MIRROR_SNIFFER_PORT2 BIT(7)
# define LAN9303_SWE_PORT_MIRROR_SNIFFER_PORT1 BIT(6)
# define LAN9303_SWE_PORT_MIRROR_SNIFFER_PORT0 BIT(5)
# define LAN9303_SWE_PORT_MIRROR_MIRRORED_PORT2 BIT(4)
# define LAN9303_SWE_PORT_MIRROR_MIRRORED_PORT1 BIT(3)
# define LAN9303_SWE_PORT_MIRROR_MIRRORED_PORT0 BIT(2)
# define LAN9303_SWE_PORT_MIRROR_ENABLE_RX_MIRRORING BIT(1)
# define LAN9303_SWE_PORT_MIRROR_ENABLE_TX_MIRRORING BIT(0)
# define LAN9303_SWE_PORT_MIRROR_DISABLED 0
#define LAN9303_SWE_INGRESS_PORT_TYPE 0x1847
#define  LAN9303_SWE_INGRESS_PORT_TYPE_VLAN 3
#define LAN9303_BM_CFG 0x1c00
#define LAN9303_BM_EGRSS_PORT_TYPE 0x1c0c
# define LAN9303_BM_EGRSS_PORT_TYPE_SPECIAL_TAG_PORT2 (BIT(17) | BIT(16))
# define LAN9303_BM_EGRSS_PORT_TYPE_SPECIAL_TAG_PORT1 (BIT(9) | BIT(8))
# define LAN9303_BM_EGRSS_PORT_TYPE_SPECIAL_TAG_PORT0 (BIT(1) | BIT(0))

#define LAN9303_SWITCH_PORT_REG(port, reg0) (0x400 * (port) + (reg0))

/* the built-in PHYs are of type LAN911X */
#define MII_LAN911X_SPECIAL_MODES 0x12
#define MII_LAN911X_SPECIAL_CONTROL_STATUS 0x1f

static const struct regmap_range lan9303_valid_regs[] = {
        regmap_reg_range(0x14, 0x17), /* misc, interrupt */
        regmap_reg_range(0x19, 0x19), /* endian test */
        regmap_reg_range(0x1d, 0x1d), /* hardware config */
        regmap_reg_range(0x23, 0x24), /* general purpose timer */
        regmap_reg_range(0x27, 0x27), /* counter */
        regmap_reg_range(0x29, 0x2a), /* PMI index regs */
        regmap_reg_range(0x68, 0x6a), /* flow control */
        regmap_reg_range(0x6b, 0x6c), /* switch fabric indirect regs */
        regmap_reg_range(0x6d, 0x6f), /* misc */
        regmap_reg_range(0x70, 0x77), /* virtual phy */
        regmap_reg_range(0x78, 0x7a), /* GPIO */
        regmap_reg_range(0x7c, 0x7e), /* MAC & reset */
        regmap_reg_range(0x80, 0xb7), /* switch fabric direct regs (wr only) */
};

static const struct regmap_range lan9303_reserved_ranges[] = {
        regmap_reg_range(0x00, 0x13),
        regmap_reg_range(0x18, 0x18),
        regmap_reg_range(0x1a, 0x1c),
        regmap_reg_range(0x1e, 0x22),
        regmap_reg_range(0x25, 0x26),
        regmap_reg_range(0x28, 0x28),
        regmap_reg_range(0x2b, 0x67),
        regmap_reg_range(0x7b, 0x7b),
        regmap_reg_range(0x7f, 0x7f),
        regmap_reg_range(0xb8, 0xff),
};

const struct regmap_access_table lan9303_register_set = {
        .yes_ranges = lan9303_valid_regs,
        .n_yes_ranges = ARRAY_SIZE(lan9303_valid_regs),
        .no_ranges = lan9303_reserved_ranges,
        .n_no_ranges = ARRAY_SIZE(lan9303_reserved_ranges),
};
EXPORT_SYMBOL(lan9303_register_set);

static int lan9303_read(struct regmap *regmap, unsigned int offset, u32 *reg)
{
        int ret, i;

        /* we can lose arbitration for the I2C case, because the device
         * tries to detect and read an external EEPROM after reset and acts as
         * a master on the shared I2C bus itself. This conflicts with our
         * attempts to access the device as a slave at the same moment.
         */
        for (i = 0; i < 5; i++) {
                ret = regmap_read(regmap, offset, reg);
                if (!ret)
                        return 0;
                if (ret != -EAGAIN)
                        break;
                msleep(500);
        }

        return -EIO;
}

static int lan9303_read_wait(struct lan9303 *chip, int offset, u32 mask)
{
        int i;

        for (i = 0; i < 25; i++) {
                u32 reg;
                int ret;

                ret = lan9303_read(chip->regmap, offset, &reg);
                if (ret) {
                        dev_err(chip->dev, "%s failed to read offset %d: %d\n",
                                __func__, offset, ret);
                        return ret;
                }
                if (!(reg & mask))
                        return 0;
                usleep_range(1000, 2000);
        }

        return -ETIMEDOUT;
}

static int lan9303_virt_phy_reg_read(struct lan9303 *chip, int regnum)
{
        int ret;
        u32 val;

        if (regnum > MII_EXPANSION)
                return -EINVAL;

        ret = lan9303_read(chip->regmap, LAN9303_VIRT_PHY_BASE + regnum, &val);
        if (ret)
                return ret;

        return val & 0xffff;
}

static int lan9303_virt_phy_reg_write(struct lan9303 *chip, int regnum, u16 val)
{
        if (regnum > MII_EXPANSION)
                return -EINVAL;

        return regmap_write(chip->regmap, LAN9303_VIRT_PHY_BASE + regnum, val);
}

static int lan9303_indirect_phy_wait_for_completion(struct lan9303 *chip)
{
        return lan9303_read_wait(chip, LAN9303_PMI_ACCESS,
                                 LAN9303_PMI_ACCESS_MII_BUSY);
}

static int lan9303_indirect_phy_read(struct lan9303 *chip, int addr, int regnum)
{
        int ret;
        u32 val;

        val = LAN9303_PMI_ACCESS_PHY_ADDR(addr);
        val |= LAN9303_PMI_ACCESS_MIIRINDA(regnum);

        mutex_lock(&chip->indirect_mutex);

        ret = lan9303_indirect_phy_wait_for_completion(chip);
        if (ret)
                goto on_error;

        /* start the MII read cycle */
        ret = regmap_write(chip->regmap, LAN9303_PMI_ACCESS, val);
        if (ret)
                goto on_error;

        ret = lan9303_indirect_phy_wait_for_completion(chip);
        if (ret)
                goto on_error;

        /* read the result of this operation */
        ret = lan9303_read(chip->regmap, LAN9303_PMI_DATA, &val);
        if (ret)
                goto on_error;

        mutex_unlock(&chip->indirect_mutex);

        return val & 0xffff;

on_error:
        mutex_unlock(&chip->indirect_mutex);
        return ret;
}

static int lan9303_indirect_phy_write(struct lan9303 *chip, int addr,
                                      int regnum, u16 val)
{
        int ret;
        u32 reg;

        reg = LAN9303_PMI_ACCESS_PHY_ADDR(addr);
        reg |= LAN9303_PMI_ACCESS_MIIRINDA(regnum);
        reg |= LAN9303_PMI_ACCESS_MII_WRITE;

        mutex_lock(&chip->indirect_mutex);

        ret = lan9303_indirect_phy_wait_for_completion(chip);
        if (ret)
                goto on_error;

        /* write the data first... */
        ret = regmap_write(chip->regmap, LAN9303_PMI_DATA, val);
        if (ret)
                goto on_error;

        /* ...then start the MII write cycle */
        ret = regmap_write(chip->regmap, LAN9303_PMI_ACCESS, reg);

on_error:
        mutex_unlock(&chip->indirect_mutex);
        return ret;
}

const struct lan9303_phy_ops lan9303_indirect_phy_ops = {
        .phy_read = lan9303_indirect_phy_read,
        .phy_write = lan9303_indirect_phy_write,
};
EXPORT_SYMBOL_GPL(lan9303_indirect_phy_ops);

static int lan9303_switch_wait_for_completion(struct lan9303 *chip)
{
        return lan9303_read_wait(chip, LAN9303_SWITCH_CSR_CMD,
                                 LAN9303_SWITCH_CSR_CMD_BUSY);
}

static int lan9303_write_switch_reg(struct lan9303 *chip, u16 regnum, u32 val)
{
        u32 reg;
        int ret;

        reg = regnum;
        reg |= LAN9303_SWITCH_CSR_CMD_LANES;
        reg |= LAN9303_SWITCH_CSR_CMD_BUSY;

        mutex_lock(&chip->indirect_mutex);

        ret = lan9303_switch_wait_for_completion(chip);
        if (ret)
                goto on_error;

        ret = regmap_write(chip->regmap, LAN9303_SWITCH_CSR_DATA, val);
        if (ret) {
                dev_err(chip->dev, "Failed to write csr data reg: %d\n", ret);
                goto on_error;
        }

        /* trigger write */
        ret = regmap_write(chip->regmap, LAN9303_SWITCH_CSR_CMD, reg);
        if (ret)
                dev_err(chip->dev, "Failed to write csr command reg: %d\n",
                        ret);

on_error:
        mutex_unlock(&chip->indirect_mutex);
        return ret;
}

static int lan9303_read_switch_reg(struct lan9303 *chip, u16 regnum, u32 *val)
{
        u32 reg;
        int ret;

        reg = regnum;
        reg |= LAN9303_SWITCH_CSR_CMD_LANES;
        reg |= LAN9303_SWITCH_CSR_CMD_RW;
        reg |= LAN9303_SWITCH_CSR_CMD_BUSY;

        mutex_lock(&chip->indirect_mutex);

        ret = lan9303_switch_wait_for_completion(chip);
        if (ret)
                goto on_error;

        /* trigger read */
        ret = regmap_write(chip->regmap, LAN9303_SWITCH_CSR_CMD, reg);
        if (ret) {
                dev_err(chip->dev, "Failed to write csr command reg: %d\n",
                        ret);
                goto on_error;
        }

        ret = lan9303_switch_wait_for_completion(chip);
        if (ret)
                goto on_error;

        ret = lan9303_read(chip->regmap, LAN9303_SWITCH_CSR_DATA, val);
        if (ret)
                dev_err(chip->dev, "Failed to read csr data reg: %d\n", ret);
on_error:
        mutex_unlock(&chip->indirect_mutex);
        return ret;
}

static int lan9303_write_switch_reg_mask(struct lan9303 *chip, u16 regnum,
                                         u32 val, u32 mask)
{
        int ret;
        u32 reg;

        ret = lan9303_read_switch_reg(chip, regnum, &reg);
        if (ret)
                return ret;

        reg = (reg & ~mask) | val;

        return lan9303_write_switch_reg(chip, regnum, reg);
}

static int lan9303_write_switch_port(struct lan9303 *chip, int port,
                                     u16 regnum, u32 val)
{
        return lan9303_write_switch_reg(
                chip, LAN9303_SWITCH_PORT_REG(port, regnum), val);
}

static int lan9303_read_switch_port(struct lan9303 *chip, int port,
                                    u16 regnum, u32 *val)
{
        return lan9303_read_switch_reg(
                chip, LAN9303_SWITCH_PORT_REG(port, regnum), val);
}

static int lan9303_detect_phy_setup(struct lan9303 *chip)
{
        int reg;

        /* Calculate chip->phy_addr_base:
         * Depending on the 'phy_addr_sel_strap' setting, the three phys are
         * using IDs 0-1-2 or IDs 1-2-3. We cannot read back the
         * 'phy_addr_sel_strap' setting directly, so we need a test, which
         * configuration is active:
         * Special reg 18 of phy 3 reads as 0x0000, if 'phy_addr_sel_strap' is 0
         * and the IDs are 0-1-2, else it contains something different from
         * 0x0000, which means 'phy_addr_sel_strap' is 1 and the IDs are 1-2-3.
         * 0xffff is returned on MDIO read with no response.
         */
        reg = chip->ops->phy_read(chip, 3, MII_LAN911X_SPECIAL_MODES);
        if (reg < 0) {
                dev_err(chip->dev, "Failed to detect phy config: %d\n", reg);
                return reg;
        }

        chip->phy_addr_base = reg != 0 && reg != 0xffff;

        dev_dbg(chip->dev, "Phy setup '%s' detected\n",
                chip->phy_addr_base ? "1-2-3" : "0-1-2");

        return 0;
}

/* Map ALR-port bits to port bitmap, and back */
static const int alrport_2_portmap[] = {1, 2, 4, 0, 3, 5, 6, 7 };
static const int portmap_2_alrport[] = {3, 0, 1, 4, 2, 5, 6, 7 };

/* Return pointer to first free ALR cache entry, return NULL if none */
static struct lan9303_alr_cache_entry *
lan9303_alr_cache_find_free(struct lan9303 *chip)
{
        int i;
        struct lan9303_alr_cache_entry *entr = chip->alr_cache;

        for (i = 0; i < LAN9303_NUM_ALR_RECORDS; i++, entr++)
                if (entr->port_map == 0)
                        return entr;

        return NULL;
}

/* Return pointer to ALR cache entry matching MAC address */
static struct lan9303_alr_cache_entry *
lan9303_alr_cache_find_mac(struct lan9303 *chip, const u8 *mac_addr)
{
        int i;
        struct lan9303_alr_cache_entry *entr = chip->alr_cache;

        BUILD_BUG_ON_MSG(sizeof(struct lan9303_alr_cache_entry) & 1,
                         "ether_addr_equal require u16 alignment");

        for (i = 0; i < LAN9303_NUM_ALR_RECORDS; i++, entr++)
                if (ether_addr_equal(entr->mac_addr, mac_addr))
                        return entr;

        return NULL;
}

static int lan9303_csr_reg_wait(struct lan9303 *chip, int regno, u32 mask)
{
        int i;

        for (i = 0; i < 25; i++) {
                u32 reg;

                lan9303_read_switch_reg(chip, regno, &reg);
                if (!(reg & mask))
                        return 0;
                usleep_range(1000, 2000);
        }

        return -ETIMEDOUT;
}

static int lan9303_alr_make_entry_raw(struct lan9303 *chip, u32 dat0, u32 dat1)
{
        lan9303_write_switch_reg(chip, LAN9303_SWE_ALR_WR_DAT_0, dat0);
        lan9303_write_switch_reg(chip, LAN9303_SWE_ALR_WR_DAT_1, dat1);
        lan9303_write_switch_reg(chip, LAN9303_SWE_ALR_CMD,
                                 LAN9303_ALR_CMD_MAKE_ENTRY);
        lan9303_csr_reg_wait(chip, LAN9303_SWE_ALR_CMD_STS, ALR_STS_MAKE_PEND);
        lan9303_write_switch_reg(chip, LAN9303_SWE_ALR_CMD, 0);

        return 0;
}

typedef int alr_loop_cb_t(struct lan9303 *chip, u32 dat0, u32 dat1,
                          int portmap, void *ctx);

static int lan9303_alr_loop(struct lan9303 *chip, alr_loop_cb_t *cb, void *ctx)
{
        int ret = 0, i;

        mutex_lock(&chip->alr_mutex);
        lan9303_write_switch_reg(chip, LAN9303_SWE_ALR_CMD,
                                 LAN9303_ALR_CMD_GET_FIRST);
        lan9303_write_switch_reg(chip, LAN9303_SWE_ALR_CMD, 0);

        for (i = 1; i < LAN9303_NUM_ALR_RECORDS; i++) {
                u32 dat0, dat1;
                int alrport, portmap;

                lan9303_read_switch_reg(chip, LAN9303_SWE_ALR_RD_DAT_0, &dat0);
                lan9303_read_switch_reg(chip, LAN9303_SWE_ALR_RD_DAT_1, &dat1);
                if (dat1 & LAN9303_ALR_DAT1_END_OF_TABL)
                        break;

                alrport = (dat1 & LAN9303_ALR_DAT1_PORT_MASK) >>
                                                LAN9303_ALR_DAT1_PORT_BITOFFS;
                portmap = alrport_2_portmap[alrport];

                ret = cb(chip, dat0, dat1, portmap, ctx);
                if (ret)
                        break;

                lan9303_write_switch_reg(chip, LAN9303_SWE_ALR_CMD,
                                         LAN9303_ALR_CMD_GET_NEXT);
                lan9303_write_switch_reg(chip, LAN9303_SWE_ALR_CMD, 0);
        }
        mutex_unlock(&chip->alr_mutex);

        return ret;
}

static void alr_reg_to_mac(u32 dat0, u32 dat1, u8 mac[6])
{
        mac[0] = (dat0 >>  0) & 0xff;
        mac[1] = (dat0 >>  8) & 0xff;
        mac[2] = (dat0 >> 16) & 0xff;
        mac[3] = (dat0 >> 24) & 0xff;
        mac[4] = (dat1 >>  0) & 0xff;
        mac[5] = (dat1 >>  8) & 0xff;
}

struct del_port_learned_ctx {
        int port;
};

/* Clear learned (non-static) entry on given port */
static int alr_loop_cb_del_port_learned(struct lan9303 *chip, u32 dat0,
                                        u32 dat1, int portmap, void *ctx)
{
        struct del_port_learned_ctx *del_ctx = ctx;
        int port = del_ctx->port;

        if (((BIT(port) & portmap) == 0) || (dat1 & LAN9303_ALR_DAT1_STATIC))
                return 0;

        /* learned entries has only one port, we can just delete */
        dat1 &= ~LAN9303_ALR_DAT1_VALID; /* delete entry */
        lan9303_alr_make_entry_raw(chip, dat0, dat1);

        return 0;
}

struct port_fdb_dump_ctx {
        int port;
        void *data;
        dsa_fdb_dump_cb_t *cb;
};

static int alr_loop_cb_fdb_port_dump(struct lan9303 *chip, u32 dat0,
                                     u32 dat1, int portmap, void *ctx)
{
        struct port_fdb_dump_ctx *dump_ctx = ctx;
        u8 mac[ETH_ALEN];
        bool is_static;

        if ((BIT(dump_ctx->port) & portmap) == 0)
                return 0;

        alr_reg_to_mac(dat0, dat1, mac);
        is_static = !!(dat1 & LAN9303_ALR_DAT1_STATIC);
        return dump_ctx->cb(mac, 0, is_static, dump_ctx->data);
}

/* Set a static ALR entry. Delete entry if port_map is zero */
static void lan9303_alr_set_entry(struct lan9303 *chip, const u8 *mac,
                                  u8 port_map, bool stp_override)
{
        u32 dat0, dat1, alr_port;

        dev_dbg(chip->dev, "%s(%pM, %d)\n", __func__, mac, port_map);
        dat1 = LAN9303_ALR_DAT1_STATIC;
        if (port_map)
                dat1 |= LAN9303_ALR_DAT1_VALID;
        /* otherwise no ports: delete entry */
        if (stp_override)
                dat1 |= LAN9303_ALR_DAT1_AGE_OVERRID;

        alr_port = portmap_2_alrport[port_map & 7];
        dat1 &= ~LAN9303_ALR_DAT1_PORT_MASK;
        dat1 |= alr_port << LAN9303_ALR_DAT1_PORT_BITOFFS;

        dat0 = 0;
        dat0 |= (mac[0] << 0);
        dat0 |= (mac[1] << 8);
        dat0 |= (mac[2] << 16);
        dat0 |= (mac[3] << 24);

        dat1 |= (mac[4] << 0);
        dat1 |= (mac[5] << 8);

        lan9303_alr_make_entry_raw(chip, dat0, dat1);
}

/* Add port to static ALR entry, create new static entry if needed */
static int lan9303_alr_add_port(struct lan9303 *chip, const u8 *mac, int port,
                                bool stp_override)
{
        struct lan9303_alr_cache_entry *entr;

        mutex_lock(&chip->alr_mutex);
        entr = lan9303_alr_cache_find_mac(chip, mac);
        if (!entr) { /*New entry */
                entr = lan9303_alr_cache_find_free(chip);
                if (!entr) {
                        mutex_unlock(&chip->alr_mutex);
                        return -ENOSPC;
                }
                ether_addr_copy(entr->mac_addr, mac);
        }
        entr->port_map |= BIT(port);
        entr->stp_override = stp_override;
        lan9303_alr_set_entry(chip, mac, entr->port_map, stp_override);
        mutex_unlock(&chip->alr_mutex);

        return 0;
}

/* Delete static port from ALR entry, delete entry if last port */
static int lan9303_alr_del_port(struct lan9303 *chip, const u8 *mac, int port)
{
        struct lan9303_alr_cache_entry *entr;

        mutex_lock(&chip->alr_mutex);
        entr = lan9303_alr_cache_find_mac(chip, mac);
        if (!entr)
                goto out;  /* no static entry found */

        entr->port_map &= ~BIT(port);
        if (entr->port_map == 0) /* zero means its free again */
                eth_zero_addr(entr->mac_addr);
        lan9303_alr_set_entry(chip, mac, entr->port_map, entr->stp_override);

out:
        mutex_unlock(&chip->alr_mutex);
        return 0;
}

static int lan9303_disable_processing_port(struct lan9303 *chip,
                                           unsigned int port)
{
        int ret;

        /* disable RX, but keep register reset default values else */
        ret = lan9303_write_switch_port(chip, port, LAN9303_MAC_RX_CFG_0,
                                        LAN9303_MAC_RX_CFG_X_REJECT_MAC_TYPES);
        if (ret)
                return ret;

        /* disable TX, but keep register reset default values else */
        return lan9303_write_switch_port(chip, port, LAN9303_MAC_TX_CFG_0,
                                LAN9303_MAC_TX_CFG_X_TX_IFG_CONFIG_DEFAULT |
                                LAN9303_MAC_TX_CFG_X_TX_PAD_ENABLE);
}

static int lan9303_enable_processing_port(struct lan9303 *chip,
                                          unsigned int port)
{
        int ret;

        /* enable RX and keep register reset default values else */
        ret = lan9303_write_switch_port(chip, port, LAN9303_MAC_RX_CFG_0,
                                        LAN9303_MAC_RX_CFG_X_REJECT_MAC_TYPES |
                                        LAN9303_MAC_RX_CFG_X_RX_ENABLE);
        if (ret)
                return ret;

        /* enable TX and keep register reset default values else */
        return lan9303_write_switch_port(chip, port, LAN9303_MAC_TX_CFG_0,
                                LAN9303_MAC_TX_CFG_X_TX_IFG_CONFIG_DEFAULT |
                                LAN9303_MAC_TX_CFG_X_TX_PAD_ENABLE |
                                LAN9303_MAC_TX_CFG_X_TX_ENABLE);
}

/* forward special tagged packets from port 0 to port 1 *or* port 2 */
static int lan9303_setup_tagging(struct lan9303 *chip)
{
        int ret;
        u32 val;
        /* enable defining the destination port via special VLAN tagging
         * for port 0
         */
        ret = lan9303_write_switch_reg(chip, LAN9303_SWE_INGRESS_PORT_TYPE,
                                       LAN9303_SWE_INGRESS_PORT_TYPE_VLAN);
        if (ret)
                return ret;

        /* tag incoming packets at port 1 and 2 on their way to port 0 to be
         * able to discover their source port
         */
        val = LAN9303_BM_EGRSS_PORT_TYPE_SPECIAL_TAG_PORT0;
        return lan9303_write_switch_reg(chip, LAN9303_BM_EGRSS_PORT_TYPE, val);
}

/* We want a special working switch:
 * - do not forward packets between port 1 and 2
 * - forward everything from port 1 to port 0
 * - forward everything from port 2 to port 0
 */
static int lan9303_separate_ports(struct lan9303 *chip)
{
        int ret;

        lan9303_alr_del_port(chip, eth_stp_addr, 0);
        ret = lan9303_write_switch_reg(chip, LAN9303_SWE_PORT_MIRROR,
                                LAN9303_SWE_PORT_MIRROR_SNIFFER_PORT0 |
                                LAN9303_SWE_PORT_MIRROR_MIRRORED_PORT1 |
                                LAN9303_SWE_PORT_MIRROR_MIRRORED_PORT2 |
                                LAN9303_SWE_PORT_MIRROR_ENABLE_RX_MIRRORING |
                                LAN9303_SWE_PORT_MIRROR_SNIFF_ALL);
        if (ret)
                return ret;

        /* prevent port 1 and 2 from forwarding packets by their own */
        return lan9303_write_switch_reg(chip, LAN9303_SWE_PORT_STATE,
                                LAN9303_SWE_PORT_STATE_FORWARDING_PORT0 |
                                LAN9303_SWE_PORT_STATE_BLOCKING_PORT1 |
                                LAN9303_SWE_PORT_STATE_BLOCKING_PORT2);
}

static void lan9303_bridge_ports(struct lan9303 *chip)
{
        /* ports bridged: remove mirroring */
        lan9303_write_switch_reg(chip, LAN9303_SWE_PORT_MIRROR,
                                 LAN9303_SWE_PORT_MIRROR_DISABLED);

        lan9303_write_switch_reg(chip, LAN9303_SWE_PORT_STATE,
                                 chip->swe_port_state);
        lan9303_alr_add_port(chip, eth_stp_addr, 0, true);
}

static void lan9303_handle_reset(struct lan9303 *chip)
{
        if (!chip->reset_gpio)
                return;

        if (chip->reset_duration != 0)
                msleep(chip->reset_duration);

        /* release (deassert) reset and activate the device */
        gpiod_set_value_cansleep(chip->reset_gpio, 0);
}

/* stop processing packets for all ports */
static int lan9303_disable_processing(struct lan9303 *chip)
{
        int p;

        for (p = 1; p < LAN9303_NUM_PORTS; p++) {
                int ret = lan9303_disable_processing_port(chip, p);

                if (ret)
                        return ret;
        }

        return 0;
}

static int lan9303_check_device(struct lan9303 *chip)
{
        int ret;
        u32 reg;

        ret = lan9303_read(chip->regmap, LAN9303_CHIP_REV, &reg);
        if (ret) {
                dev_err(chip->dev, "failed to read chip revision register: %d\n",
                        ret);
                if (!chip->reset_gpio) {
                        dev_dbg(chip->dev,
                                "hint: maybe failed due to missing reset GPIO\n");
                }
                return ret;
        }

        if ((reg >> 16) != LAN9303_CHIP_ID) {
                dev_err(chip->dev, "expecting LAN9303 chip, but found: %X\n",
                        reg >> 16);
                return -ENODEV;
        }

        /* The default state of the LAN9303 device is to forward packets between
         * all ports (if not configured differently by an external EEPROM).
         * The initial state of a DSA device must be forwarding packets only
         * between the external and the internal ports and no forwarding
         * between the external ports. In preparation we stop packet handling
         * at all for now until the LAN9303 device is re-programmed accordingly.
         */
        ret = lan9303_disable_processing(chip);
        if (ret)
                dev_warn(chip->dev, "failed to disable switching %d\n", ret);

        dev_info(chip->dev, "Found LAN9303 rev. %u\n", reg & 0xffff);

        ret = lan9303_detect_phy_setup(chip);
        if (ret) {
                dev_err(chip->dev,
                        "failed to discover phy bootstrap setup: %d\n", ret);
                return ret;
        }

        return 0;
}

/* ---------------------------- DSA -----------------------------------*/

static enum dsa_tag_protocol lan9303_get_tag_protocol(struct dsa_switch *ds,
                                                      int port,
                                                      enum dsa_tag_protocol mp)
{
        return DSA_TAG_PROTO_LAN9303;
}

static int lan9303_setup(struct dsa_switch *ds)
{
        struct lan9303 *chip = ds->priv;
        int ret;

        /* Make sure that port 0 is the cpu port */
        if (!dsa_is_cpu_port(ds, 0)) {
                dev_err(chip->dev, "port 0 is not the CPU port\n");
                return -EINVAL;
        }

        ret = lan9303_setup_tagging(chip);
        if (ret)
                dev_err(chip->dev, "failed to setup port tagging %d\n", ret);

        ret = lan9303_separate_ports(chip);
        if (ret)
                dev_err(chip->dev, "failed to separate ports %d\n", ret);

        ret = lan9303_enable_processing_port(chip, 0);
        if (ret)
                dev_err(chip->dev, "failed to re-enable switching %d\n", ret);

        /* Trap IGMP to port 0 */
        ret = lan9303_write_switch_reg_mask(chip, LAN9303_SWE_GLB_INGRESS_CFG,
                                            LAN9303_SWE_GLB_INGR_IGMP_TRAP |
                                            LAN9303_SWE_GLB_INGR_IGMP_PORT(0),
                                            LAN9303_SWE_GLB_INGR_IGMP_PORT(1) |
                                            LAN9303_SWE_GLB_INGR_IGMP_PORT(2));
        if (ret)
                dev_err(chip->dev, "failed to setup IGMP trap %d\n", ret);

        return 0;
}

struct lan9303_mib_desc {
        unsigned int offset; /* offset of first MAC */
        const char *name;
};

static const struct lan9303_mib_desc lan9303_mib[] = {
        { .offset = LAN9303_MAC_RX_BRDCST_CNT_0, .name = "RxBroad", },
        { .offset = LAN9303_MAC_RX_PAUSE_CNT_0, .name = "RxPause", },
        { .offset = LAN9303_MAC_RX_MULCST_CNT_0, .name = "RxMulti", },
        { .offset = LAN9303_MAC_RX_PKTOK_CNT_0, .name = "RxOk", },
        { .offset = LAN9303_MAC_RX_CRCERR_CNT_0, .name = "RxCrcErr", },
        { .offset = LAN9303_MAC_RX_ALIGN_CNT_0, .name = "RxAlignErr", },
        { .offset = LAN9303_MAC_RX_JABB_CNT_0, .name = "RxJabber", },
        { .offset = LAN9303_MAC_RX_FRAG_CNT_0, .name = "RxFragment", },
        { .offset = LAN9303_MAC_RX_64_CNT_0, .name = "Rx64Byte", },
        { .offset = LAN9303_MAC_RX_127_CNT_0, .name = "Rx128Byte", },
        { .offset = LAN9303_MAC_RX_255_CNT_0, .name = "Rx256Byte", },
        { .offset = LAN9303_MAC_RX_511_CNT_0, .name = "Rx512Byte", },
        { .offset = LAN9303_MAC_RX_1023_CNT_0, .name = "Rx1024Byte", },
        { .offset = LAN9303_MAC_RX_MAX_CNT_0, .name = "RxMaxByte", },
        { .offset = LAN9303_MAC_RX_PKTLEN_CNT_0, .name = "RxByteCnt", },
        { .offset = LAN9303_MAC_RX_SYMBL_CNT_0, .name = "RxSymbolCnt", },
        { .offset = LAN9303_MAC_RX_CTLFRM_CNT_0, .name = "RxCfs", },
        { .offset = LAN9303_MAC_RX_OVRSZE_CNT_0, .name = "RxOverFlow", },
        { .offset = LAN9303_MAC_TX_UNDSZE_CNT_0, .name = "TxShort", },
        { .offset = LAN9303_MAC_TX_BRDCST_CNT_0, .name = "TxBroad", },
        { .offset = LAN9303_MAC_TX_PAUSE_CNT_0, .name = "TxPause", },
        { .offset = LAN9303_MAC_TX_MULCST_CNT_0, .name = "TxMulti", },
        { .offset = LAN9303_MAC_RX_UNDSZE_CNT_0, .name = "TxUnderRun", },
        { .offset = LAN9303_MAC_TX_64_CNT_0, .name = "Tx64Byte", },
        { .offset = LAN9303_MAC_TX_127_CNT_0, .name = "Tx128Byte", },
        { .offset = LAN9303_MAC_TX_255_CNT_0, .name = "Tx256Byte", },
        { .offset = LAN9303_MAC_TX_511_CNT_0, .name = "Tx512Byte", },
        { .offset = LAN9303_MAC_TX_1023_CNT_0, .name = "Tx1024Byte", },
        { .offset = LAN9303_MAC_TX_MAX_CNT_0, .name = "TxMaxByte", },
        { .offset = LAN9303_MAC_TX_PKTLEN_CNT_0, .name = "TxByteCnt", },
        { .offset = LAN9303_MAC_TX_PKTOK_CNT_0, .name = "TxOk", },
        { .offset = LAN9303_MAC_TX_TOTALCOL_CNT_0, .name = "TxCollision", },
        { .offset = LAN9303_MAC_TX_MULTICOL_CNT_0, .name = "TxMultiCol", },
        { .offset = LAN9303_MAC_TX_SNGLECOL_CNT_0, .name = "TxSingleCol", },
        { .offset = LAN9303_MAC_TX_EXCOL_CNT_0, .name = "TxExcCol", },
        { .offset = LAN9303_MAC_TX_DEFER_CNT_0, .name = "TxDefer", },
        { .offset = LAN9303_MAC_TX_LATECOL_0, .name = "TxLateCol", },
};

static void lan9303_get_strings(struct dsa_switch *ds, int port,
                                u32 stringset, uint8_t *data)
{
        unsigned int u;

        if (stringset != ETH_SS_STATS)
                return;

        for (u = 0; u < ARRAY_SIZE(lan9303_mib); u++) {
                strncpy(data + u * ETH_GSTRING_LEN, lan9303_mib[u].name,
                        ETH_GSTRING_LEN);
        }
}

static void lan9303_get_ethtool_stats(struct dsa_switch *ds, int port,
                                      uint64_t *data)
{
        struct lan9303 *chip = ds->priv;
        unsigned int u;

        for (u = 0; u < ARRAY_SIZE(lan9303_mib); u++) {
                u32 reg;

                int ret;

                ret = lan9303_read_switch_port(
                        chip, port, lan9303_mib[u].offset, &reg);

                if (ret)
                        dev_warn(chip->dev, "Reading status port %d reg %u failed\n",
                                 port, lan9303_mib[u].offset);
                data[u] = reg;
        }
}

static int lan9303_get_sset_count(struct dsa_switch *ds, int port, int sset)
{
        if (sset != ETH_SS_STATS)
                return 0;

        return ARRAY_SIZE(lan9303_mib);
}

static int lan9303_phy_read(struct dsa_switch *ds, int phy, int regnum)
{
        struct lan9303 *chip = ds->priv;
        int phy_base = chip->phy_addr_base;

        if (phy == phy_base)
                return lan9303_virt_phy_reg_read(chip, regnum);
        if (phy > phy_base + 2)
                return -ENODEV;

        return chip->ops->phy_read(chip, phy, regnum);
}

static int lan9303_phy_write(struct dsa_switch *ds, int phy, int regnum,
                             u16 val)
{
        struct lan9303 *chip = ds->priv;
        int phy_base = chip->phy_addr_base;

        if (phy == phy_base)
                return lan9303_virt_phy_reg_write(chip, regnum, val);
        if (phy > phy_base + 2)
                return -ENODEV;

        return chip->ops->phy_write(chip, phy, regnum, val);
}

static void lan9303_adjust_link(struct dsa_switch *ds, int port,
                                struct phy_device *phydev)
{
        struct lan9303 *chip = ds->priv;
        int ctl;

        if (!phy_is_pseudo_fixed_link(phydev))
                return;

        ctl = lan9303_phy_read(ds, port, MII_BMCR);

        ctl &= ~BMCR_ANENABLE;

        if (phydev->speed == SPEED_100)
                ctl |= BMCR_SPEED100;
        else if (phydev->speed == SPEED_10)
                ctl &= ~BMCR_SPEED100;
        else
                dev_err(ds->dev, "unsupported speed: %d\n", phydev->speed);

        if (phydev->duplex == DUPLEX_FULL)
                ctl |= BMCR_FULLDPLX;
        else
                ctl &= ~BMCR_FULLDPLX;

        lan9303_phy_write(ds, port, MII_BMCR, ctl);

        if (port == chip->phy_addr_base) {
                /* Virtual Phy: Remove Turbo 200Mbit mode */
                lan9303_read(chip->regmap, LAN9303_VIRT_SPECIAL_CTRL, &ctl);

                ctl &= ~LAN9303_VIRT_SPECIAL_TURBO;
                regmap_write(chip->regmap, LAN9303_VIRT_SPECIAL_CTRL, ctl);
        }
}

static int lan9303_port_enable(struct dsa_switch *ds, int port,
                               struct phy_device *phy)
{
        struct dsa_port *dp = dsa_to_port(ds, port);
        struct lan9303 *chip = ds->priv;

        if (!dsa_port_is_user(dp))
                return 0;

        vlan_vid_add(dp->cpu_dp->master, htons(ETH_P_8021Q), port);

        return lan9303_enable_processing_port(chip, port);
}

static void lan9303_port_disable(struct dsa_switch *ds, int port)
{
        struct dsa_port *dp = dsa_to_port(ds, port);
        struct lan9303 *chip = ds->priv;

        if (!dsa_port_is_user(dp))
                return;

        vlan_vid_del(dp->cpu_dp->master, htons(ETH_P_8021Q), port);

        lan9303_disable_processing_port(chip, port);
        lan9303_phy_write(ds, chip->phy_addr_base + port, MII_BMCR, BMCR_PDOWN);
}

static int lan9303_port_bridge_join(struct dsa_switch *ds, int port,
                                    struct dsa_bridge bridge,
                                    bool *tx_fwd_offload,
                                    struct netlink_ext_ack *extack)
{
        struct lan9303 *chip = ds->priv;

        dev_dbg(chip->dev, "%s(port %d)\n", __func__, port);
        if (dsa_port_bridge_same(dsa_to_port(ds, 1), dsa_to_port(ds, 2))) {
                lan9303_bridge_ports(chip);
                chip->is_bridged = true;  /* unleash stp_state_set() */
        }

        return 0;
}

static void lan9303_port_bridge_leave(struct dsa_switch *ds, int port,
                                      struct dsa_bridge bridge)
{
        struct lan9303 *chip = ds->priv;

        dev_dbg(chip->dev, "%s(port %d)\n", __func__, port);
        if (chip->is_bridged) {
                lan9303_separate_ports(chip);
                chip->is_bridged = false;
        }
}

static void lan9303_port_stp_state_set(struct dsa_switch *ds, int port,
                                       u8 state)
{
        int portmask, portstate;
        struct lan9303 *chip = ds->priv;

        dev_dbg(chip->dev, "%s(port %d, state %d)\n",
                __func__, port, state);

        switch (state) {
        case BR_STATE_DISABLED:
                portstate = LAN9303_SWE_PORT_STATE_DISABLED_PORT0;
                break;
        case BR_STATE_BLOCKING:
        case BR_STATE_LISTENING:
                portstate = LAN9303_SWE_PORT_STATE_BLOCKING_PORT0;
                break;
        case BR_STATE_LEARNING:
                portstate = LAN9303_SWE_PORT_STATE_LEARNING_PORT0;
                break;
        case BR_STATE_FORWARDING:
                portstate = LAN9303_SWE_PORT_STATE_FORWARDING_PORT0;
                break;
        default:
                portstate = LAN9303_SWE_PORT_STATE_DISABLED_PORT0;
                dev_err(chip->dev, "unknown stp state: port %d, state %d\n",
                        port, state);
        }

        portmask = 0x3 << (port * 2);
        portstate <<= (port * 2);

        chip->swe_port_state = (chip->swe_port_state & ~portmask) | portstate;

        if (chip->is_bridged)
                lan9303_write_switch_reg(chip, LAN9303_SWE_PORT_STATE,
                                         chip->swe_port_state);
        /* else: touching SWE_PORT_STATE would break port separation */
}

static void lan9303_port_fast_age(struct dsa_switch *ds, int port)
{
        struct lan9303 *chip = ds->priv;
        struct del_port_learned_ctx del_ctx = {
                .port = port,
        };

        dev_dbg(chip->dev, "%s(%d)\n", __func__, port);
        lan9303_alr_loop(chip, alr_loop_cb_del_port_learned, &del_ctx);
}

static int lan9303_port_fdb_add(struct dsa_switch *ds, int port,
                                const unsigned char *addr, u16 vid,
                                struct dsa_db db)
{
        struct lan9303 *chip = ds->priv;

        dev_dbg(chip->dev, "%s(%d, %pM, %d)\n", __func__, port, addr, vid);
        if (vid)
                return -EOPNOTSUPP;

        return lan9303_alr_add_port(chip, addr, port, false);
}

static int lan9303_port_fdb_del(struct dsa_switch *ds, int port,
                                const unsigned char *addr, u16 vid,
                                struct dsa_db db)
{
        struct lan9303 *chip = ds->priv;

        dev_dbg(chip->dev, "%s(%d, %pM, %d)\n", __func__, port, addr, vid);
        if (vid)
                return -EOPNOTSUPP;
        lan9303_alr_del_port(chip, addr, port);

        return 0;
}

static int lan9303_port_fdb_dump(struct dsa_switch *ds, int port,
                                 dsa_fdb_dump_cb_t *cb, void *data)
{
        struct lan9303 *chip = ds->priv;
        struct port_fdb_dump_ctx dump_ctx = {
                .port = port,
                .data = data,
                .cb   = cb,
        };

        dev_dbg(chip->dev, "%s(%d)\n", __func__, port);
        return lan9303_alr_loop(chip, alr_loop_cb_fdb_port_dump, &dump_ctx);
}

static int lan9303_port_mdb_prepare(struct dsa_switch *ds, int port,
                                    const struct switchdev_obj_port_mdb *mdb)
{
        struct lan9303 *chip = ds->priv;

        dev_dbg(chip->dev, "%s(%d, %pM, %d)\n", __func__, port, mdb->addr,
                mdb->vid);
        if (mdb->vid)
                return -EOPNOTSUPP;
        if (lan9303_alr_cache_find_mac(chip, mdb->addr))
                return 0;
        if (!lan9303_alr_cache_find_free(chip))
                return -ENOSPC;

        return 0;
}

static int lan9303_port_mdb_add(struct dsa_switch *ds, int port,
                                const struct switchdev_obj_port_mdb *mdb,
                                struct dsa_db db)
{
        struct lan9303 *chip = ds->priv;
        int err;

        err = lan9303_port_mdb_prepare(ds, port, mdb);
        if (err)
                return err;

        dev_dbg(chip->dev, "%s(%d, %pM, %d)\n", __func__, port, mdb->addr,
                mdb->vid);
        return lan9303_alr_add_port(chip, mdb->addr, port, false);
}

static int lan9303_port_mdb_del(struct dsa_switch *ds, int port,
                                const struct switchdev_obj_port_mdb *mdb,
                                struct dsa_db db)
{
        struct lan9303 *chip = ds->priv;

        dev_dbg(chip->dev, "%s(%d, %pM, %d)\n", __func__, port, mdb->addr,
                mdb->vid);
        if (mdb->vid)
                return -EOPNOTSUPP;
        lan9303_alr_del_port(chip, mdb->addr, port);

        return 0;
}

static const struct dsa_switch_ops lan9303_switch_ops = {
        .get_tag_protocol = lan9303_get_tag_protocol,
        .setup = lan9303_setup,
        .get_strings = lan9303_get_strings,
        .phy_read = lan9303_phy_read,
        .phy_write = lan9303_phy_write,
        .adjust_link = lan9303_adjust_link,
        .get_ethtool_stats = lan9303_get_ethtool_stats,
        .get_sset_count = lan9303_get_sset_count,
        .port_enable = lan9303_port_enable,
        .port_disable = lan9303_port_disable,
        .port_bridge_join       = lan9303_port_bridge_join,
        .port_bridge_leave      = lan9303_port_bridge_leave,
        .port_stp_state_set     = lan9303_port_stp_state_set,
        .port_fast_age          = lan9303_port_fast_age,
        .port_fdb_add           = lan9303_port_fdb_add,
        .port_fdb_del           = lan9303_port_fdb_del,
        .port_fdb_dump          = lan9303_port_fdb_dump,
        .port_mdb_add           = lan9303_port_mdb_add,
        .port_mdb_del           = lan9303_port_mdb_del,
};

static int lan9303_register_switch(struct lan9303 *chip)
{
        int base;

        chip->ds = devm_kzalloc(chip->dev, sizeof(*chip->ds), GFP_KERNEL);
        if (!chip->ds)
                return -ENOMEM;

        chip->ds->dev = chip->dev;
        chip->ds->num_ports = LAN9303_NUM_PORTS;
        chip->ds->priv = chip;
        chip->ds->ops = &lan9303_switch_ops;
        base = chip->phy_addr_base;
        chip->ds->phys_mii_mask = GENMASK(LAN9303_NUM_PORTS - 1 + base, base);

        return dsa_register_switch(chip->ds);
}

static int lan9303_probe_reset_gpio(struct lan9303 *chip,
                                     struct device_node *np)
{
        chip->reset_gpio = devm_gpiod_get_optional(chip->dev, "reset",
                                                   GPIOD_OUT_HIGH);
        if (IS_ERR(chip->reset_gpio))
                return PTR_ERR(chip->reset_gpio);

        if (!chip->reset_gpio) {
                dev_dbg(chip->dev, "No reset GPIO defined\n");
                return 0;
        }

        chip->reset_duration = 200;

        if (np) {
                of_property_read_u32(np, "reset-duration",
                                     &chip->reset_duration);
        } else {
                dev_dbg(chip->dev, "reset duration defaults to 200 ms\n");
        }

        /* A sane reset duration should not be longer than 1s */
        if (chip->reset_duration > 1000)
                chip->reset_duration = 1000;

        return 0;
}

int lan9303_probe(struct lan9303 *chip, struct device_node *np)
{
        int ret;

        mutex_init(&chip->indirect_mutex);
        mutex_init(&chip->alr_mutex);

        ret = lan9303_probe_reset_gpio(chip, np);
        if (ret)
                return ret;

        lan9303_handle_reset(chip);

        ret = lan9303_check_device(chip);
        if (ret)
                return ret;

        ret = lan9303_register_switch(chip);
        if (ret) {
                dev_dbg(chip->dev, "Failed to register switch: %d\n", ret);
                return ret;
        }

        return 0;
}
EXPORT_SYMBOL(lan9303_probe);

int lan9303_remove(struct lan9303 *chip)
{
        int rc;

        rc = lan9303_disable_processing(chip);
        if (rc != 0)
                dev_warn(chip->dev, "shutting down failed\n");

        dsa_unregister_switch(chip->ds);

        /* assert reset to the whole device to prevent it from doing anything */
        gpiod_set_value_cansleep(chip->reset_gpio, 1);
        gpiod_unexport(chip->reset_gpio);

        return 0;
}
EXPORT_SYMBOL(lan9303_remove);

void lan9303_shutdown(struct lan9303 *chip)
{
        dsa_switch_shutdown(chip->ds);
}
EXPORT_SYMBOL(lan9303_shutdown);

MODULE_AUTHOR("Juergen Borleis <kernel@pengutronix.de>");
MODULE_DESCRIPTION("Core driver for SMSC/Microchip LAN9303 three port ethernet switch");
MODULE_LICENSE("GPL v2");