// SPDX-License-Identifier: GPL-2.0+
/*
 * Nvidia line card driver
 *
 * Copyright (C) 2020 Nvidia Technologies Ltd.
 */

#include <linux/device.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/platform_data/mlxcpld.h>
#include <linux/platform_data/mlxreg.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

/* I2C bus IO offsets */
#define MLXREG_LC_REG_CPLD1_VER_OFFSET          0x2500
#define MLXREG_LC_REG_FPGA1_VER_OFFSET          0x2501
#define MLXREG_LC_REG_CPLD1_PN_OFFSET           0x2504
#define MLXREG_LC_REG_FPGA1_PN_OFFSET           0x2506
#define MLXREG_LC_REG_RESET_CAUSE_OFFSET        0x251d
#define MLXREG_LC_REG_LED1_OFFSET               0x2520
#define MLXREG_LC_REG_GP0_OFFSET                0x252e
#define MLXREG_LC_REG_FIELD_UPGRADE             0x2534
#define MLXREG_LC_CHANNEL_I2C_REG               0x25dc
#define MLXREG_LC_REG_CPLD1_MVER_OFFSET         0x25de
#define MLXREG_LC_REG_FPGA1_MVER_OFFSET         0x25df
#define MLXREG_LC_REG_MAX_POWER_OFFSET          0x25f1
#define MLXREG_LC_REG_CONFIG_OFFSET             0x25fb
#define MLXREG_LC_REG_MAX                       0x3fff

/**
 * enum mlxreg_lc_type - line cards types
 *
 * @MLXREG_LC_SN4800_C16: 100GbE line card with 16 QSFP28 ports;
 */
enum mlxreg_lc_type {
        MLXREG_LC_SN4800_C16 = 0x0000,
};

/**
 * enum mlxreg_lc_state - line cards state
 *
 * @MLXREG_LC_INITIALIZED: line card is initialized;
 * @MLXREG_LC_POWERED: line card is powered;
 * @MLXREG_LC_SYNCED: line card is synchronized between hardware and firmware;
 */
enum mlxreg_lc_state {
        MLXREG_LC_INITIALIZED = BIT(0),
        MLXREG_LC_POWERED = BIT(1),
        MLXREG_LC_SYNCED = BIT(2),
};

#define MLXREG_LC_CONFIGURED    (MLXREG_LC_INITIALIZED | MLXREG_LC_POWERED | MLXREG_LC_SYNCED)

/* mlxreg_lc - device private data
 * @dev: platform device;
 * @lock: line card lock;
 * @par_regmap: parent device regmap handle;
 * @data: platform core data;
 * @io_data: register access platform data;
 * @led_data: LED platform data;
 * @mux_data: MUX platform data;
 * @led: LED device;
 * @io_regs: register access device;
 * @mux_brdinfo: mux configuration;
 * @mux: mux devices;
 * @aux_devs: I2C devices feeding by auxiliary power;
 * @aux_devs_num: number of I2C devices feeding by auxiliary power;
 * @main_devs: I2C devices feeding by main power;
 * @main_devs_num: number of I2C devices feeding by main power;
 * @state: line card state;
 */
struct mlxreg_lc {
        struct device *dev;
        struct mutex lock; /* line card access lock */
        void *par_regmap;
        struct mlxreg_core_data *data;
        struct mlxreg_core_platform_data *io_data;
        struct mlxreg_core_platform_data *led_data;
        struct mlxcpld_mux_plat_data *mux_data;
        struct platform_device *led;
        struct platform_device *io_regs;
        struct i2c_board_info *mux_brdinfo;
        struct platform_device *mux;
        struct mlxreg_hotplug_device *aux_devs;
        int aux_devs_num;
        struct mlxreg_hotplug_device *main_devs;
        int main_devs_num;
        enum mlxreg_lc_state state;
};

static bool mlxreg_lc_writeable_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case MLXREG_LC_REG_LED1_OFFSET:
        case MLXREG_LC_REG_GP0_OFFSET:
        case MLXREG_LC_REG_FIELD_UPGRADE:
        case MLXREG_LC_CHANNEL_I2C_REG:
                return true;
        }
        return false;
}

static bool mlxreg_lc_readable_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case MLXREG_LC_REG_CPLD1_VER_OFFSET:
        case MLXREG_LC_REG_FPGA1_VER_OFFSET:
        case MLXREG_LC_REG_CPLD1_PN_OFFSET:
        case MLXREG_LC_REG_FPGA1_PN_OFFSET:
        case MLXREG_LC_REG_RESET_CAUSE_OFFSET:
        case MLXREG_LC_REG_LED1_OFFSET:
        case MLXREG_LC_REG_GP0_OFFSET:
        case MLXREG_LC_REG_FIELD_UPGRADE:
        case MLXREG_LC_CHANNEL_I2C_REG:
        case MLXREG_LC_REG_CPLD1_MVER_OFFSET:
        case MLXREG_LC_REG_FPGA1_MVER_OFFSET:
        case MLXREG_LC_REG_MAX_POWER_OFFSET:
        case MLXREG_LC_REG_CONFIG_OFFSET:
                return true;
        }
        return false;
}

static bool mlxreg_lc_volatile_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case MLXREG_LC_REG_CPLD1_VER_OFFSET:
        case MLXREG_LC_REG_FPGA1_VER_OFFSET:
        case MLXREG_LC_REG_CPLD1_PN_OFFSET:
        case MLXREG_LC_REG_FPGA1_PN_OFFSET:
        case MLXREG_LC_REG_RESET_CAUSE_OFFSET:
        case MLXREG_LC_REG_LED1_OFFSET:
        case MLXREG_LC_REG_GP0_OFFSET:
        case MLXREG_LC_REG_FIELD_UPGRADE:
        case MLXREG_LC_CHANNEL_I2C_REG:
        case MLXREG_LC_REG_CPLD1_MVER_OFFSET:
        case MLXREG_LC_REG_FPGA1_MVER_OFFSET:
        case MLXREG_LC_REG_MAX_POWER_OFFSET:
        case MLXREG_LC_REG_CONFIG_OFFSET:
                return true;
        }
        return false;
}

static const struct reg_default mlxreg_lc_regmap_default[] = {
        { MLXREG_LC_CHANNEL_I2C_REG, 0x00 },
};

/* Configuration for the register map of a device with 2 bytes address space. */
static const struct regmap_config mlxreg_lc_regmap_conf = {
        .reg_bits = 16,
        .val_bits = 8,
        .max_register = MLXREG_LC_REG_MAX,
        .cache_type = REGCACHE_FLAT,
        .writeable_reg = mlxreg_lc_writeable_reg,
        .readable_reg = mlxreg_lc_readable_reg,
        .volatile_reg = mlxreg_lc_volatile_reg,
        .reg_defaults = mlxreg_lc_regmap_default,
        .num_reg_defaults = ARRAY_SIZE(mlxreg_lc_regmap_default),
};

/* Default channels vector.
 * It contains only the channels, which physically connected to the devices,
 * empty channels are skipped.
 */
static int mlxreg_lc_chan[] = {
        0x04, 0x05, 0x06, 0x07, 0x08, 0x10, 0x20, 0x21, 0x22, 0x23, 0x40, 0x41,
        0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d,
        0x4e, 0x4f
};

/* Default mux configuration. */
static struct mlxcpld_mux_plat_data mlxreg_lc_mux_data[] = {
        {
                .chan_ids = mlxreg_lc_chan,
                .num_adaps = ARRAY_SIZE(mlxreg_lc_chan),
                .sel_reg_addr = MLXREG_LC_CHANNEL_I2C_REG,
                .reg_size = 2,
        },
};

/* Default mux board info. */
static struct i2c_board_info mlxreg_lc_mux_brdinfo = {
        I2C_BOARD_INFO("i2c-mux-mlxcpld", 0x32),
};

/* Line card default auxiliary power static devices. */
static struct i2c_board_info mlxreg_lc_aux_pwr_devices[] = {
        {
                I2C_BOARD_INFO("24c32", 0x51),
        },
        {
                I2C_BOARD_INFO("24c32", 0x51),
        },
};

/* Line card default auxiliary power board info. */
static struct mlxreg_hotplug_device mlxreg_lc_aux_pwr_brdinfo[] = {
        {
                .brdinfo = &mlxreg_lc_aux_pwr_devices[0],
                .nr = 3,
        },
        {
                .brdinfo = &mlxreg_lc_aux_pwr_devices[1],
                .nr = 4,
        },
};

/* Line card default main power static devices. */
static struct i2c_board_info mlxreg_lc_main_pwr_devices[] = {
        {
                I2C_BOARD_INFO("mp2975", 0x62),
        },
        {
                I2C_BOARD_INFO("mp2975", 0x64),
        },
        {
                I2C_BOARD_INFO("max11603", 0x6d),
        },
        {
                I2C_BOARD_INFO("lm25066", 0x15),
        },
};

/* Line card default main power board info. */
static struct mlxreg_hotplug_device mlxreg_lc_main_pwr_brdinfo[] = {
        {
                .brdinfo = &mlxreg_lc_main_pwr_devices[0],
                .nr = 0,
        },
        {
                .brdinfo = &mlxreg_lc_main_pwr_devices[1],
                .nr = 0,
        },
        {
                .brdinfo = &mlxreg_lc_main_pwr_devices[2],
                .nr = 1,
        },
        {
                .brdinfo = &mlxreg_lc_main_pwr_devices[3],
                .nr = 2,
        },
};

/* LED default data. */
static struct mlxreg_core_data mlxreg_lc_led_data[] = {
        {
                .label = "status:green",
                .reg = MLXREG_LC_REG_LED1_OFFSET,
                .mask = GENMASK(7, 4),
        },
        {
                .label = "status:orange",
                .reg = MLXREG_LC_REG_LED1_OFFSET,
                .mask = GENMASK(7, 4),
        },
};

static struct mlxreg_core_platform_data mlxreg_lc_led = {
        .identity = "pci",
        .data = mlxreg_lc_led_data,
        .counter = ARRAY_SIZE(mlxreg_lc_led_data),
};

/* Default register access data. */
static struct mlxreg_core_data mlxreg_lc_io_data[] = {
        {
                .label = "cpld1_version",
                .reg = MLXREG_LC_REG_CPLD1_VER_OFFSET,
                .bit = GENMASK(7, 0),
                .mode = 0444,
        },
        {
                .label = "fpga1_version",
                .reg = MLXREG_LC_REG_FPGA1_VER_OFFSET,
                .bit = GENMASK(7, 0),
                .mode = 0444,
        },
        {
                .label = "cpld1_pn",
                .reg = MLXREG_LC_REG_CPLD1_PN_OFFSET,
                .bit = GENMASK(15, 0),
                .mode = 0444,
                .regnum = 2,
        },
        {
                .label = "fpga1_pn",
                .reg = MLXREG_LC_REG_FPGA1_PN_OFFSET,
                .bit = GENMASK(15, 0),
                .mode = 0444,
                .regnum = 2,
        },
        {
                .label = "cpld1_version_min",
                .reg = MLXREG_LC_REG_CPLD1_MVER_OFFSET,
                .bit = GENMASK(7, 0),
                .mode = 0444,
        },
        {
                .label = "fpga1_version_min",
                .reg = MLXREG_LC_REG_FPGA1_MVER_OFFSET,
                .bit = GENMASK(7, 0),
                .mode = 0444,
        },
        {
                .label = "reset_fpga_not_done",
                .reg = MLXREG_LC_REG_RESET_CAUSE_OFFSET,
                .mask = GENMASK(7, 0) & ~BIT(1),
                .mode = 0444,
        },
        {
                .label = "reset_aux_pwr_or_ref",
                .reg = MLXREG_LC_REG_RESET_CAUSE_OFFSET,
                .mask = GENMASK(7, 0) & ~BIT(2),
                .mode = 0444,
        },
        {
                .label = "reset_dc_dc_pwr_fail",
                .reg = MLXREG_LC_REG_RESET_CAUSE_OFFSET,
                .mask = GENMASK(7, 0) & ~BIT(3),
                .mode = 0444,
        },
        {
                .label = "reset_from_chassis",
                .reg = MLXREG_LC_REG_RESET_CAUSE_OFFSET,
                .mask = GENMASK(7, 0) & ~BIT(4),
                .mode = 0444,
        },
        {
                .label = "reset_pwr_off_from_chassis",
                .reg = MLXREG_LC_REG_RESET_CAUSE_OFFSET,
                .mask = GENMASK(7, 0) & ~BIT(5),
                .mode = 0444,
        },
        {
                .label = "reset_line_card",
                .reg = MLXREG_LC_REG_RESET_CAUSE_OFFSET,
                .mask = GENMASK(7, 0) & ~BIT(6),
                .mode = 0444,
        },
        {
                .label = "reset_line_card_pwr_en",
                .reg = MLXREG_LC_REG_RESET_CAUSE_OFFSET,
                .mask = GENMASK(7, 0) & ~BIT(7),
                .mode = 0444,
        },
        {
                .label = "cpld_upgrade_en",
                .reg = MLXREG_LC_REG_FIELD_UPGRADE,
                .mask = GENMASK(7, 0) & ~BIT(0),
                .mode = 0644,
                .secured = 1,
        },
        {
                .label = "fpga_upgrade_en",
                .reg = MLXREG_LC_REG_FIELD_UPGRADE,
                .mask = GENMASK(7, 0) & ~BIT(1),
                .mode = 0644,
                .secured = 1,
        },
        {
                .label = "qsfp_pwr_en",
                .reg = MLXREG_LC_REG_GP0_OFFSET,
                .mask = GENMASK(7, 0) & ~BIT(0),
                .mode = 0644,
        },
        {
                .label = "vpd_wp",
                .reg = MLXREG_LC_REG_GP0_OFFSET,
                .mask = GENMASK(7, 0) & ~BIT(3),
                .mode = 0644,
                .secured = 1,
        },
        {
                .label = "agb_spi_burn_en",
                .reg = MLXREG_LC_REG_GP0_OFFSET,
                .mask = GENMASK(7, 0) & ~BIT(5),
                .mode = 0644,
                .secured = 1,
        },
        {
                .label = "fpga_spi_burn_en",
                .reg = MLXREG_LC_REG_GP0_OFFSET,
                .mask = GENMASK(7, 0) & ~BIT(6),
                .mode = 0644,
                .secured = 1,
        },
        {
                .label = "max_power",
                .reg = MLXREG_LC_REG_MAX_POWER_OFFSET,
                .bit = GENMASK(15, 0),
                .mode = 0444,
                .regnum = 2,
        },
        {
                .label = "config",
                .reg = MLXREG_LC_REG_CONFIG_OFFSET,
                .bit = GENMASK(15, 0),
                .mode = 0444,
                .regnum = 2,
        },
};

static struct mlxreg_core_platform_data mlxreg_lc_regs_io = {
        .data = mlxreg_lc_io_data,
        .counter = ARRAY_SIZE(mlxreg_lc_io_data),
};

static int
mlxreg_lc_create_static_devices(struct mlxreg_lc *mlxreg_lc, struct mlxreg_hotplug_device *devs,
                                int size)
{
        struct mlxreg_hotplug_device *dev = devs;
        int i, ret;

        /* Create static I2C device feeding by auxiliary or main power. */
        for (i = 0; i < size; i++, dev++) {
                dev->client = i2c_new_client_device(dev->adapter, dev->brdinfo);
                if (IS_ERR(dev->client)) {
                        dev_err(mlxreg_lc->dev, "Failed to create client %s at bus %d at addr 0x%02x\n",
                                dev->brdinfo->type, dev->nr, dev->brdinfo->addr);

                        dev->adapter = NULL;
                        ret = PTR_ERR(dev->client);
                        goto fail_create_static_devices;
                }
        }

        return 0;

fail_create_static_devices:
        while (--i >= 0) {
                dev = devs + i;
                i2c_unregister_device(dev->client);
                dev->client = NULL;
        }
        return ret;
}

static void
mlxreg_lc_destroy_static_devices(struct mlxreg_lc *mlxreg_lc, struct mlxreg_hotplug_device *devs,
                                 int size)
{
        struct mlxreg_hotplug_device *dev = devs;
        int i;

        /* Destroy static I2C device feeding by auxiliary or main power. */
        for (i = 0; i < size; i++, dev++) {
                if (dev->client) {
                        i2c_unregister_device(dev->client);
                        dev->client = NULL;
                }
        }
}

static int mlxreg_lc_power_on_off(struct mlxreg_lc *mlxreg_lc, u8 action)
{
        u32 regval;
        int err;

        err = regmap_read(mlxreg_lc->par_regmap, mlxreg_lc->data->reg_pwr, &regval);
        if (err)
                goto regmap_read_fail;

        if (action)
                regval |= BIT(mlxreg_lc->data->slot - 1);
        else
                regval &= ~BIT(mlxreg_lc->data->slot - 1);

        err = regmap_write(mlxreg_lc->par_regmap, mlxreg_lc->data->reg_pwr, regval);

regmap_read_fail:
        return err;
}

static int mlxreg_lc_enable_disable(struct mlxreg_lc *mlxreg_lc, bool action)
{
        u32 regval;
        int err;

        /*
         * Hardware holds the line card after powering on in the disabled state. Holding line card
         * in disabled state protects access to the line components, like FPGA and gearboxes.
         * Line card should be enabled in order to get it in operational state. Line card could be
         * disabled for moving it to non-operational state. Enabling line card does not affect the
         * line card which is already has been enabled. Disabling does not affect the disabled line
         * card.
         */
        err = regmap_read(mlxreg_lc->par_regmap, mlxreg_lc->data->reg_ena, &regval);
        if (err)
                goto regmap_read_fail;

        if (action)
                regval |= BIT(mlxreg_lc->data->slot - 1);
        else
                regval &= ~BIT(mlxreg_lc->data->slot - 1);

        err = regmap_write(mlxreg_lc->par_regmap, mlxreg_lc->data->reg_ena, regval);

regmap_read_fail:
        return err;
}

static int
mlxreg_lc_sn4800_c16_config_init(struct mlxreg_lc *mlxreg_lc, void *regmap,
                                 struct mlxreg_core_data *data)
{
        struct device *dev = &data->hpdev.client->dev;

        /* Set line card configuration according to the type. */
        mlxreg_lc->mux_data = mlxreg_lc_mux_data;
        mlxreg_lc->io_data = &mlxreg_lc_regs_io;
        mlxreg_lc->led_data = &mlxreg_lc_led;
        mlxreg_lc->mux_brdinfo = &mlxreg_lc_mux_brdinfo;

        mlxreg_lc->aux_devs = devm_kmemdup(dev, mlxreg_lc_aux_pwr_brdinfo,
                                           sizeof(mlxreg_lc_aux_pwr_brdinfo), GFP_KERNEL);
        if (!mlxreg_lc->aux_devs)
                return -ENOMEM;
        mlxreg_lc->aux_devs_num = ARRAY_SIZE(mlxreg_lc_aux_pwr_brdinfo);
        mlxreg_lc->main_devs = devm_kmemdup(dev, mlxreg_lc_main_pwr_brdinfo,
                                            sizeof(mlxreg_lc_main_pwr_brdinfo), GFP_KERNEL);
        if (!mlxreg_lc->main_devs)
                return -ENOMEM;
        mlxreg_lc->main_devs_num = ARRAY_SIZE(mlxreg_lc_main_pwr_brdinfo);

        return 0;
}

static void
mlxreg_lc_state_update(struct mlxreg_lc *mlxreg_lc, enum mlxreg_lc_state state, u8 action)
{
        if (action)
                mlxreg_lc->state |= state;
        else
                mlxreg_lc->state &= ~state;
}

static void
mlxreg_lc_state_update_locked(struct mlxreg_lc *mlxreg_lc, enum mlxreg_lc_state state, u8 action)
{
        mutex_lock(&mlxreg_lc->lock);

        if (action)
                mlxreg_lc->state |= state;
        else
                mlxreg_lc->state &= ~state;

        mutex_unlock(&mlxreg_lc->lock);
}

/*
 * Callback is to be called from mlxreg-hotplug driver to notify about line card about received
 * event.
 */
static int mlxreg_lc_event_handler(void *handle, enum mlxreg_hotplug_kind kind, u8 action)
{
        struct mlxreg_lc *mlxreg_lc = handle;
        int err = 0;

        dev_info(mlxreg_lc->dev, "linecard#%d state %d event kind %d action %d\n",
                 mlxreg_lc->data->slot, mlxreg_lc->state, kind, action);

        mutex_lock(&mlxreg_lc->lock);
        if (!(mlxreg_lc->state & MLXREG_LC_INITIALIZED))
                goto mlxreg_lc_non_initialzed_exit;

        switch (kind) {
        case MLXREG_HOTPLUG_LC_SYNCED:
                /*
                 * Synchronization event - hardware and firmware are synchronized. Power on/off
                 * line card - to allow/disallow main power source.
                 */
                mlxreg_lc_state_update(mlxreg_lc, MLXREG_LC_SYNCED, action);
                /* Power line card if it is not powered yet. */
                if (!(mlxreg_lc->state & MLXREG_LC_POWERED) && action) {
                        err = mlxreg_lc_power_on_off(mlxreg_lc, 1);
                        if (err)
                                goto mlxreg_lc_power_on_off_fail;
                }
                /* In case line card is configured - enable it. */
                if (mlxreg_lc->state & MLXREG_LC_CONFIGURED && action)
                        err = mlxreg_lc_enable_disable(mlxreg_lc, 1);
                break;
        case MLXREG_HOTPLUG_LC_POWERED:
                /* Power event - attach or de-attach line card device feeding by the main power. */
                if (action) {
                        /* Do not create devices, if line card is already powered. */
                        if (mlxreg_lc->state & MLXREG_LC_POWERED) {
                                /* In case line card is configured - enable it. */
                                if (mlxreg_lc->state & MLXREG_LC_CONFIGURED)
                                        err = mlxreg_lc_enable_disable(mlxreg_lc, 1);

                                goto mlxreg_lc_enable_disable_exit;
                        }
                        err = mlxreg_lc_create_static_devices(mlxreg_lc, mlxreg_lc->main_devs,
                                                              mlxreg_lc->main_devs_num);
                        if (err)
                                goto mlxreg_lc_create_static_devices_fail;

                        /* In case line card is already in ready state - enable it. */
                        if (mlxreg_lc->state & MLXREG_LC_CONFIGURED)
                                err = mlxreg_lc_enable_disable(mlxreg_lc, 1);
                } else {
                        mlxreg_lc_destroy_static_devices(mlxreg_lc, mlxreg_lc->main_devs,
                                                         mlxreg_lc->main_devs_num);
                }
                mlxreg_lc_state_update(mlxreg_lc, MLXREG_LC_POWERED, action);
                break;
        case MLXREG_HOTPLUG_LC_READY:
                /*
                 * Ready event – enable line card by releasing it from reset or disable it by put
                 * to reset state.
                 */
                err = mlxreg_lc_enable_disable(mlxreg_lc, !!action);
                break;
        case MLXREG_HOTPLUG_LC_THERMAL:
                /* Thermal shutdown event – power off line card. */
                if (action)
                        err = mlxreg_lc_power_on_off(mlxreg_lc, 0);
                break;
        default:
                break;
        }

mlxreg_lc_enable_disable_exit:
mlxreg_lc_power_on_off_fail:
mlxreg_lc_create_static_devices_fail:
mlxreg_lc_non_initialzed_exit:
        mutex_unlock(&mlxreg_lc->lock);

        return err;
}

/*
 * Callback is to be called from i2c-mux-mlxcpld driver to indicate that all adapter devices has
 * been created.
 */
static int mlxreg_lc_completion_notify(void *handle, struct i2c_adapter *parent,
                                       struct i2c_adapter *adapters[])
{
        struct mlxreg_hotplug_device *main_dev, *aux_dev;
        struct mlxreg_lc *mlxreg_lc = handle;
        u32 regval;
        int i, err;

        /* Update I2C devices feeding by auxiliary power. */
        aux_dev = mlxreg_lc->aux_devs;
        for (i = 0; i < mlxreg_lc->aux_devs_num; i++, aux_dev++) {
                aux_dev->adapter = adapters[aux_dev->nr];
                aux_dev->nr = adapters[aux_dev->nr]->nr;
        }

        err = mlxreg_lc_create_static_devices(mlxreg_lc, mlxreg_lc->aux_devs,
                                              mlxreg_lc->aux_devs_num);
        if (err)
                return err;

        /* Update I2C devices feeding by main power. */
        main_dev = mlxreg_lc->main_devs;
        for (i = 0; i < mlxreg_lc->main_devs_num; i++, main_dev++) {
                main_dev->adapter = adapters[main_dev->nr];
                main_dev->nr = adapters[main_dev->nr]->nr;
        }

        /* Verify if line card is powered. */
        err = regmap_read(mlxreg_lc->par_regmap, mlxreg_lc->data->reg_pwr, &regval);
        if (err)
                goto mlxreg_lc_regmap_read_power_fail;

        if (regval & mlxreg_lc->data->mask) {
                err = mlxreg_lc_create_static_devices(mlxreg_lc, mlxreg_lc->main_devs,
                                                      mlxreg_lc->main_devs_num);
                if (err)
                        goto mlxreg_lc_create_static_devices_failed;

                mlxreg_lc_state_update_locked(mlxreg_lc, MLXREG_LC_POWERED, 1);
        }

        /* Verify if line card is synchronized. */
        err = regmap_read(mlxreg_lc->par_regmap, mlxreg_lc->data->reg_sync, &regval);
        if (err)
                goto mlxreg_lc_regmap_read_sync_fail;

        /* Power on line card if necessary. */
        if (regval & mlxreg_lc->data->mask) {
                mlxreg_lc->state |= MLXREG_LC_SYNCED;
                mlxreg_lc_state_update_locked(mlxreg_lc, MLXREG_LC_SYNCED, 1);
                if (!(mlxreg_lc->state & MLXREG_LC_POWERED)) {
                        err = mlxreg_lc_power_on_off(mlxreg_lc, 1);
                        if (err)
                                goto mlxreg_lc_regmap_power_on_off_fail;
                }
        }

        mlxreg_lc_state_update_locked(mlxreg_lc, MLXREG_LC_INITIALIZED, 1);

        return 0;

mlxreg_lc_regmap_power_on_off_fail:
mlxreg_lc_regmap_read_sync_fail:
        if (mlxreg_lc->state & MLXREG_LC_POWERED)
                mlxreg_lc_destroy_static_devices(mlxreg_lc, mlxreg_lc->main_devs,
                                                 mlxreg_lc->main_devs_num);
mlxreg_lc_create_static_devices_failed:
        mlxreg_lc_destroy_static_devices(mlxreg_lc, mlxreg_lc->aux_devs, mlxreg_lc->aux_devs_num);
mlxreg_lc_regmap_read_power_fail:
        return err;
}

static int
mlxreg_lc_config_init(struct mlxreg_lc *mlxreg_lc, void *regmap,
                      struct mlxreg_core_data *data)
{
        struct device *dev = &data->hpdev.client->dev;
        int lsb, err;
        u32 regval;

        /* Validate line card type. */
        err = regmap_read(regmap, MLXREG_LC_REG_CONFIG_OFFSET, &lsb);
        err = (!err) ? regmap_read(regmap, MLXREG_LC_REG_CONFIG_OFFSET, &regval) : err;
        if (err)
                return err;
        regval = (regval & GENMASK(7, 0)) << 8 | (lsb & GENMASK(7, 0));
        switch (regval) {
        case MLXREG_LC_SN4800_C16:
                err = mlxreg_lc_sn4800_c16_config_init(mlxreg_lc, regmap, data);
                if (err) {
                        dev_err(dev, "Failed to config client %s at bus %d at addr 0x%02x\n",
                                data->hpdev.brdinfo->type, data->hpdev.nr,
                                data->hpdev.brdinfo->addr);
                        return err;
                }
                break;
        default:
                return -ENODEV;
        }

        /* Create mux infrastructure. */
        mlxreg_lc->mux_data->handle = mlxreg_lc;
        mlxreg_lc->mux_data->completion_notify = mlxreg_lc_completion_notify;
        mlxreg_lc->mux_brdinfo->platform_data = mlxreg_lc->mux_data;
        mlxreg_lc->mux = platform_device_register_resndata(dev, "i2c-mux-mlxcpld", data->hpdev.nr,
                                                           NULL, 0, mlxreg_lc->mux_data,
                                                           sizeof(*mlxreg_lc->mux_data));
        if (IS_ERR(mlxreg_lc->mux)) {
                dev_err(dev, "Failed to create mux infra for client %s at bus %d at addr 0x%02x\n",
                        data->hpdev.brdinfo->type, data->hpdev.nr, data->hpdev.brdinfo->addr);
                return PTR_ERR(mlxreg_lc->mux);
        }

        /* Register IO access driver. */
        if (mlxreg_lc->io_data) {
                mlxreg_lc->io_data->regmap = regmap;
                mlxreg_lc->io_regs =
                platform_device_register_resndata(dev, "mlxreg-io", data->hpdev.nr, NULL, 0,
                                                  mlxreg_lc->io_data, sizeof(*mlxreg_lc->io_data));
                if (IS_ERR(mlxreg_lc->io_regs)) {
                        dev_err(dev, "Failed to create region for client %s at bus %d at addr 0x%02x\n",
                                data->hpdev.brdinfo->type, data->hpdev.nr,
                                data->hpdev.brdinfo->addr);
                        err = PTR_ERR(mlxreg_lc->io_regs);
                        goto fail_register_io;
                }
        }

        /* Register LED driver. */
        if (mlxreg_lc->led_data) {
                mlxreg_lc->led_data->regmap = regmap;
                mlxreg_lc->led =
                platform_device_register_resndata(dev, "leds-mlxreg", data->hpdev.nr, NULL, 0,
                                                  mlxreg_lc->led_data,
                                                  sizeof(*mlxreg_lc->led_data));
                if (IS_ERR(mlxreg_lc->led)) {
                        dev_err(dev, "Failed to create LED objects for client %s at bus %d at addr 0x%02x\n",
                                data->hpdev.brdinfo->type, data->hpdev.nr,
                                data->hpdev.brdinfo->addr);
                        err = PTR_ERR(mlxreg_lc->led);
                        goto fail_register_led;
                }
        }

        return 0;

fail_register_led:
        if (mlxreg_lc->io_regs)
                platform_device_unregister(mlxreg_lc->io_regs);
fail_register_io:
        if (mlxreg_lc->mux)
                platform_device_unregister(mlxreg_lc->mux);

        return err;
}

static void mlxreg_lc_config_exit(struct mlxreg_lc *mlxreg_lc)
{
        /* Unregister LED driver. */
        if (mlxreg_lc->led)
                platform_device_unregister(mlxreg_lc->led);
        /* Unregister IO access driver. */
        if (mlxreg_lc->io_regs)
                platform_device_unregister(mlxreg_lc->io_regs);
        /* Remove mux infrastructure. */
        if (mlxreg_lc->mux)
                platform_device_unregister(mlxreg_lc->mux);
}

static int mlxreg_lc_probe(struct platform_device *pdev)
{
        struct mlxreg_core_hotplug_platform_data *par_pdata;
        struct mlxreg_core_data *data;
        struct mlxreg_lc *mlxreg_lc;
        void *regmap;
        int i, err;

        data = dev_get_platdata(&pdev->dev);
        if (!data)
                return -EINVAL;

        mlxreg_lc = devm_kzalloc(&pdev->dev, sizeof(*mlxreg_lc), GFP_KERNEL);
        if (!mlxreg_lc)
                return -ENOMEM;

        mutex_init(&mlxreg_lc->lock);
        /* Set event notification callback. */
        data->notifier->user_handler = mlxreg_lc_event_handler;
        data->notifier->handle = mlxreg_lc;

        data->hpdev.adapter = i2c_get_adapter(data->hpdev.nr);
        if (!data->hpdev.adapter) {
                dev_err(&pdev->dev, "Failed to get adapter for bus %d\n",
                        data->hpdev.nr);
                err = -EFAULT;
                goto i2c_get_adapter_fail;
        }

        /* Create device at the top of line card I2C tree.*/
        data->hpdev.client = i2c_new_client_device(data->hpdev.adapter,
                                                   data->hpdev.brdinfo);
        if (IS_ERR(data->hpdev.client)) {
                dev_err(&pdev->dev, "Failed to create client %s at bus %d at addr 0x%02x\n",
                        data->hpdev.brdinfo->type, data->hpdev.nr, data->hpdev.brdinfo->addr);
                err = PTR_ERR(data->hpdev.client);
                goto i2c_new_device_fail;
        }

        regmap = devm_regmap_init_i2c(data->hpdev.client,
                                      &mlxreg_lc_regmap_conf);
        if (IS_ERR(regmap)) {
                dev_err(&pdev->dev, "Failed to create regmap for client %s at bus %d at addr 0x%02x\n",
                        data->hpdev.brdinfo->type, data->hpdev.nr, data->hpdev.brdinfo->addr);
                err = PTR_ERR(regmap);
                goto devm_regmap_init_i2c_fail;
        }

        /* Set default registers. */
        for (i = 0; i < mlxreg_lc_regmap_conf.num_reg_defaults; i++) {
                err = regmap_write(regmap, mlxreg_lc_regmap_default[i].reg,
                                   mlxreg_lc_regmap_default[i].def);
                if (err) {
                        dev_err(&pdev->dev, "Failed to set default regmap %d for client %s at bus %d at addr 0x%02x\n",
                                i, data->hpdev.brdinfo->type, data->hpdev.nr,
                                data->hpdev.brdinfo->addr);
                        goto regmap_write_fail;
                }
        }

        /* Sync registers with hardware. */
        regcache_mark_dirty(regmap);
        err = regcache_sync(regmap);
        if (err) {
                dev_err(&pdev->dev, "Failed to sync regmap for client %s at bus %d at addr 0x%02x\n",
                        data->hpdev.brdinfo->type, data->hpdev.nr, data->hpdev.brdinfo->addr);
                goto regcache_sync_fail;
        }

        par_pdata = data->hpdev.brdinfo->platform_data;
        mlxreg_lc->par_regmap = par_pdata->regmap;
        mlxreg_lc->data = data;
        mlxreg_lc->dev = &pdev->dev;
        platform_set_drvdata(pdev, mlxreg_lc);

        /* Configure line card. */
        err = mlxreg_lc_config_init(mlxreg_lc, regmap, data);
        if (err)
                goto mlxreg_lc_config_init_fail;

        return 0;

mlxreg_lc_config_init_fail:
regcache_sync_fail:
regmap_write_fail:
devm_regmap_init_i2c_fail:
        i2c_unregister_device(data->hpdev.client);
        data->hpdev.client = NULL;
i2c_new_device_fail:
        i2c_put_adapter(data->hpdev.adapter);
        data->hpdev.adapter = NULL;
i2c_get_adapter_fail:
        /* Clear event notification callback and handle. */
        if (data->notifier) {
                data->notifier->user_handler = NULL;
                data->notifier->handle = NULL;
        }
        return err;
}

static void mlxreg_lc_remove(struct platform_device *pdev)
{
        struct mlxreg_core_data *data = dev_get_platdata(&pdev->dev);
        struct mlxreg_lc *mlxreg_lc = platform_get_drvdata(pdev);

        mlxreg_lc_state_update_locked(mlxreg_lc, MLXREG_LC_INITIALIZED, 0);

        /*
         * Probing and removing are invoked by hotplug events raised upon line card insertion and
         * removing. If probing procedure fails all data is cleared. However, hotplug event still
         * will be raised on line card removing and activate removing procedure. In this case there
         * is nothing to remove.
         */
        if (!data->notifier || !data->notifier->handle)
                return;

        /* Clear event notification callback and handle. */
        data->notifier->user_handler = NULL;
        data->notifier->handle = NULL;

        /* Destroy static I2C device feeding by main power. */
        mlxreg_lc_destroy_static_devices(mlxreg_lc, mlxreg_lc->main_devs,
                                         mlxreg_lc->main_devs_num);
        /* Destroy static I2C device feeding by auxiliary power. */
        mlxreg_lc_destroy_static_devices(mlxreg_lc, mlxreg_lc->aux_devs, mlxreg_lc->aux_devs_num);
        /* Unregister underlying drivers. */
        mlxreg_lc_config_exit(mlxreg_lc);
        if (data->hpdev.client) {
                i2c_unregister_device(data->hpdev.client);
                data->hpdev.client = NULL;
                i2c_put_adapter(data->hpdev.adapter);
                data->hpdev.adapter = NULL;
        }
}

static struct platform_driver mlxreg_lc_driver = {
        .probe = mlxreg_lc_probe,
        .remove = mlxreg_lc_remove,
        .driver = {
                .name = "mlxreg-lc",
        },
};

module_platform_driver(mlxreg_lc_driver);

MODULE_AUTHOR("Vadim Pasternak <vadimp@nvidia.com>");
MODULE_DESCRIPTION("Nvidia line card platform driver");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_ALIAS("platform:mlxreg-lc");