// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Microchip ksz series register access through SPI
 *
 * Copyright (C) 2017-2024 Microchip Technology Inc.
 *      Tristram Ha <Tristram.Ha@microchip.com>
 */

#include <linux/unaligned.h>

#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/spi/spi.h>

#include "ksz_common.h"

#define KSZ8463_SPI_ADDR_SHIFT                  13
#define KSZ8463_SPI_ADDR_ALIGN                  3
#define KSZ8463_SPI_TURNAROUND_SHIFT            2

#define KSZ8795_SPI_ADDR_SHIFT                  12
#define KSZ8795_SPI_ADDR_ALIGN                  3
#define KSZ8795_SPI_TURNAROUND_SHIFT            1

#define KSZ8863_SPI_ADDR_SHIFT                  8
#define KSZ8863_SPI_ADDR_ALIGN                  8
#define KSZ8863_SPI_TURNAROUND_SHIFT            0

#define KSZ9477_SPI_ADDR_SHIFT                  24
#define KSZ9477_SPI_ADDR_ALIGN                  3
#define KSZ9477_SPI_TURNAROUND_SHIFT            5

KSZ_REGMAP_TABLE(ksz8795, 16, KSZ8795_SPI_ADDR_SHIFT,
                 KSZ8795_SPI_TURNAROUND_SHIFT, KSZ8795_SPI_ADDR_ALIGN);

KSZ_REGMAP_TABLE(ksz8863, 16, KSZ8863_SPI_ADDR_SHIFT,
                 KSZ8863_SPI_TURNAROUND_SHIFT, KSZ8863_SPI_ADDR_ALIGN);

KSZ_REGMAP_TABLE(ksz9477, 32, KSZ9477_SPI_ADDR_SHIFT,
                 KSZ9477_SPI_TURNAROUND_SHIFT, KSZ9477_SPI_ADDR_ALIGN);

static u16 ksz8463_reg(u16 reg, size_t size)
{
        switch (size) {
        case 1:
                reg = ((reg >> 2) << 4) | (1 << (reg & 3));
                break;
        case 2:
                reg = ((reg >> 2) << 4) | (reg & 2 ? 0x0c : 0x03);
                break;
        default:
                reg = ((reg >> 2) << 4) | 0xf;
                break;
        }
        reg <<= KSZ8463_SPI_TURNAROUND_SHIFT;
        return reg;
}

static int ksz8463_spi_read(void *context,
                            const void *reg, size_t reg_size,
                            void *val, size_t val_size)
{
        struct device *dev = context;
        struct spi_device *spi = to_spi_device(dev);
        u8 bytes[2];
        u16 cmd;
        int rc;

        if (reg_size > 2 || val_size > 4)
                return -EINVAL;
        memcpy(&cmd, reg, sizeof(u16));
        cmd = ksz8463_reg(cmd, val_size);
        /* SPI command uses big-endian format. */
        put_unaligned_be16(cmd, bytes);
        rc = spi_write_then_read(spi, bytes, reg_size, val, val_size);
#if defined(__BIG_ENDIAN)
        /* Register value uses little-endian format so need to convert when
         * running in big-endian system.
         */
        if (!rc && val_size > 1) {
                if (val_size == 2) {
                        u16 v = get_unaligned_le16(val);

                        memcpy(val, &v, sizeof(v));
                } else if (val_size == 4) {
                        u32 v = get_unaligned_le32(val);

                        memcpy(val, &v, sizeof(v));
                }
        }
#endif
        return rc;
}

static int ksz8463_spi_write(void *context, const void *data, size_t count)
{
        struct device *dev = context;
        struct spi_device *spi = to_spi_device(dev);
        size_t val_size = count - 2;
        u8 bytes[6];
        u16 cmd;

        if (count <= 2 || count > 6)
                return -EINVAL;
        memcpy(bytes, data, count);
        memcpy(&cmd, data, sizeof(u16));
        cmd = ksz8463_reg(cmd, val_size);
        cmd |= (1 << (KSZ8463_SPI_ADDR_SHIFT + KSZ8463_SPI_TURNAROUND_SHIFT));
        /* SPI command uses big-endian format. */
        put_unaligned_be16(cmd, bytes);
#if defined(__BIG_ENDIAN)
        /* Register value uses little-endian format so need to convert when
         * running in big-endian system.
         */
        if (val_size == 2) {
                u8 *val = &bytes[2];
                u16 v;

                memcpy(&v, val, sizeof(v));
                put_unaligned_le16(v, val);
        } else if (val_size == 4) {
                u8 *val = &bytes[2];
                u32 v;

                memcpy(&v, val, sizeof(v));
                put_unaligned_le32(v, val);
        }
#endif
        return spi_write(spi, bytes, count);
}

KSZ8463_REGMAP_TABLE(ksz8463, KSZ8463_SPI_ADDR_SHIFT, 0,
                     KSZ8463_SPI_ADDR_ALIGN);

static int ksz_spi_probe(struct spi_device *spi)
{
        const struct regmap_config *regmap_config;
        const struct ksz_chip_data *chip;
        struct device *ddev = &spi->dev;
        struct regmap_config rc;
        struct ksz_device *dev;
        int i, ret = 0;

        dev = ksz_switch_alloc(&spi->dev, spi);
        if (!dev)
                return -ENOMEM;

        chip = device_get_match_data(ddev);
        if (!chip)
                return -EINVAL;

        /* Save chip id to do special initialization when probing. */
        dev->chip_id = chip->chip_id;
        if (chip->chip_id == KSZ88X3_CHIP_ID)
                regmap_config = ksz8863_regmap_config;
        else if (chip->chip_id == KSZ8463_CHIP_ID)
                regmap_config = ksz8463_regmap_config;
        else if (chip->chip_id == KSZ8795_CHIP_ID ||
                 chip->chip_id == KSZ8794_CHIP_ID ||
                 chip->chip_id == KSZ8765_CHIP_ID)
                regmap_config = ksz8795_regmap_config;
        else if (chip->chip_id == KSZ8895_CHIP_ID ||
                 chip->chip_id == KSZ8864_CHIP_ID)
                regmap_config = ksz8863_regmap_config;
        else
                regmap_config = ksz9477_regmap_config;

        for (i = 0; i < __KSZ_NUM_REGMAPS; i++) {
                rc = regmap_config[i];
                rc.lock_arg = &dev->regmap_mutex;
                rc.wr_table = chip->wr_table;
                rc.rd_table = chip->rd_table;
                dev->regmap[i] = devm_regmap_init_spi(spi, &rc);

                if (IS_ERR(dev->regmap[i])) {
                        return dev_err_probe(&spi->dev, PTR_ERR(dev->regmap[i]),
                                             "Failed to initialize regmap%i\n",
                                             regmap_config[i].val_bits);
                }
        }

        if (spi->dev.platform_data)
                dev->pdata = spi->dev.platform_data;

        /* setup spi */
        spi->mode = SPI_MODE_3;
        ret = spi_setup(spi);
        if (ret)
                return ret;

        dev->irq = spi->irq;

        ret = ksz_switch_register(dev);

        /* Main DSA driver may not be started yet. */
        if (ret)
                return ret;

        spi_set_drvdata(spi, dev);

        return 0;
}

static void ksz_spi_remove(struct spi_device *spi)
{
        struct ksz_device *dev = spi_get_drvdata(spi);

        if (dev)
                ksz_switch_remove(dev);
}

static void ksz_spi_shutdown(struct spi_device *spi)
{
        struct ksz_device *dev = spi_get_drvdata(spi);

        if (!dev)
                return;

        ksz_switch_shutdown(dev);

        spi_set_drvdata(spi, NULL);
}

static const struct of_device_id ksz_dt_ids[] = {
        {
                .compatible = "microchip,ksz8463",
                .data = &ksz_switch_chips[KSZ8463]
        },
        {
                .compatible = "microchip,ksz8765",
                .data = &ksz_switch_chips[KSZ8765]
        },
        {
                .compatible = "microchip,ksz8794",
                .data = &ksz_switch_chips[KSZ8794]
        },
        {
                .compatible = "microchip,ksz8795",
                .data = &ksz_switch_chips[KSZ8795]
        },
        {
                .compatible = "microchip,ksz8863",
                .data = &ksz_switch_chips[KSZ88X3]
        },
        {
                .compatible = "microchip,ksz8864",
                .data = &ksz_switch_chips[KSZ8864]
        },
        {
                .compatible = "microchip,ksz8873",
                .data = &ksz_switch_chips[KSZ88X3]
        },
        {
                .compatible = "microchip,ksz8895",
                .data = &ksz_switch_chips[KSZ8895]
        },
        {
                .compatible = "microchip,ksz9477",
                .data = &ksz_switch_chips[KSZ9477]
        },
        {
                .compatible = "microchip,ksz9896",
                .data = &ksz_switch_chips[KSZ9896]
        },
        {
                .compatible = "microchip,ksz9897",
                .data = &ksz_switch_chips[KSZ9897]
        },
        {
                .compatible = "microchip,ksz9893",
                .data = &ksz_switch_chips[KSZ9893]
        },
        {
                .compatible = "microchip,ksz9563",
                .data = &ksz_switch_chips[KSZ9563]
        },
        {
                .compatible = "microchip,ksz8563",
                .data = &ksz_switch_chips[KSZ8563]
        },
        {
                .compatible = "microchip,ksz8567",
                .data = &ksz_switch_chips[KSZ8567]
        },
        {
                .compatible = "microchip,ksz9567",
                .data = &ksz_switch_chips[KSZ9567]
        },
        {
                .compatible = "microchip,lan9370",
                .data = &ksz_switch_chips[LAN9370]
        },
        {
                .compatible = "microchip,lan9371",
                .data = &ksz_switch_chips[LAN9371]
        },
        {
                .compatible = "microchip,lan9372",
                .data = &ksz_switch_chips[LAN9372]
        },
        {
                .compatible = "microchip,lan9373",
                .data = &ksz_switch_chips[LAN9373]
        },
        {
                .compatible = "microchip,lan9374",
                .data = &ksz_switch_chips[LAN9374]
        },
        {
                .compatible = "microchip,lan9646",
                .data = &ksz_switch_chips[LAN9646]
        },
        {},
};
MODULE_DEVICE_TABLE(of, ksz_dt_ids);

static const struct spi_device_id ksz_spi_ids[] = {
        { "ksz8463" },
        { "ksz8765" },
        { "ksz8794" },
        { "ksz8795" },
        { "ksz8863" },
        { "ksz8864" },
        { "ksz8873" },
        { "ksz8895" },
        { "ksz9477" },
        { "ksz9896" },
        { "ksz9897" },
        { "ksz9893" },
        { "ksz9563" },
        { "ksz8563" },
        { "ksz8567" },
        { "ksz9567" },
        { "lan9370" },
        { "lan9371" },
        { "lan9372" },
        { "lan9373" },
        { "lan9374" },
        { "lan9646" },
        { },
};
MODULE_DEVICE_TABLE(spi, ksz_spi_ids);

static DEFINE_SIMPLE_DEV_PM_OPS(ksz_spi_pm_ops,
                                ksz_switch_suspend, ksz_switch_resume);

static struct spi_driver ksz_spi_driver = {
        .driver = {
                .name   = "ksz-switch",
                .of_match_table = ksz_dt_ids,
                .pm = &ksz_spi_pm_ops,
        },
        .id_table = ksz_spi_ids,
        .probe  = ksz_spi_probe,
        .remove = ksz_spi_remove,
        .shutdown = ksz_spi_shutdown,
};

module_spi_driver(ksz_spi_driver);

MODULE_ALIAS("spi:lan937x");
MODULE_AUTHOR("Tristram Ha <Tristram.Ha@microchip.com>");
MODULE_DESCRIPTION("Microchip ksz Series Switch SPI Driver");
MODULE_LICENSE("GPL");