// SPDX-License-Identifier: GPL-2.0-only
/*
 * Altera Arria10 DevKit System Resource MFD Driver
 *
 * Author: Thor Thayer <tthayer@opensource.altera.com>
 *
 * Copyright Intel Corporation (C) 2014-2016. All Rights Reserved
 *
 * SPI access for Altera Arria10 MAX5 System Resource Chip
 *
 * Adapted from DA9052
 */

#include <linux/mfd/altera-a10sr.h>
#include <linux/mfd/core.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/spi/spi.h>

static const struct mfd_cell altr_a10sr_subdev_info[] = {
        {
                .name = "altr_a10sr_gpio",
                .of_compatible = "altr,a10sr-gpio",
        },
        {
                .name = "altr_a10sr_reset",
                .of_compatible = "altr,a10sr-reset",
        },
};

static bool altr_a10sr_reg_readable(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case ALTR_A10SR_VERSION_READ:
        case ALTR_A10SR_LED_REG:
        case ALTR_A10SR_PBDSW_REG:
        case ALTR_A10SR_PBDSW_IRQ_REG:
        case ALTR_A10SR_PWR_GOOD1_REG:
        case ALTR_A10SR_PWR_GOOD2_REG:
        case ALTR_A10SR_PWR_GOOD3_REG:
        case ALTR_A10SR_FMCAB_REG:
        case ALTR_A10SR_HPS_RST_REG:
        case ALTR_A10SR_USB_QSPI_REG:
        case ALTR_A10SR_SFPA_REG:
        case ALTR_A10SR_SFPB_REG:
        case ALTR_A10SR_I2C_M_REG:
        case ALTR_A10SR_WARM_RST_REG:
        case ALTR_A10SR_WR_KEY_REG:
        case ALTR_A10SR_PMBUS_REG:
                return true;
        default:
                return false;
        }
}

static bool altr_a10sr_reg_writeable(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case ALTR_A10SR_LED_REG:
        case ALTR_A10SR_PBDSW_IRQ_REG:
        case ALTR_A10SR_FMCAB_REG:
        case ALTR_A10SR_HPS_RST_REG:
        case ALTR_A10SR_USB_QSPI_REG:
        case ALTR_A10SR_SFPA_REG:
        case ALTR_A10SR_SFPB_REG:
        case ALTR_A10SR_WARM_RST_REG:
        case ALTR_A10SR_WR_KEY_REG:
        case ALTR_A10SR_PMBUS_REG:
                return true;
        default:
                return false;
        }
}

static bool altr_a10sr_reg_volatile(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case ALTR_A10SR_PBDSW_REG:
        case ALTR_A10SR_PBDSW_IRQ_REG:
        case ALTR_A10SR_PWR_GOOD1_REG:
        case ALTR_A10SR_PWR_GOOD2_REG:
        case ALTR_A10SR_PWR_GOOD3_REG:
        case ALTR_A10SR_HPS_RST_REG:
        case ALTR_A10SR_I2C_M_REG:
        case ALTR_A10SR_WARM_RST_REG:
        case ALTR_A10SR_WR_KEY_REG:
        case ALTR_A10SR_PMBUS_REG:
                return true;
        default:
                return false;
        }
}

static const struct regmap_config altr_a10sr_regmap_config = {
        .reg_bits = 8,
        .val_bits = 8,

        .cache_type = REGCACHE_NONE,

        .use_single_read = true,
        .use_single_write = true,
        .read_flag_mask = 1,
        .write_flag_mask = 0,

        .max_register = ALTR_A10SR_WR_KEY_REG,
        .readable_reg = altr_a10sr_reg_readable,
        .writeable_reg = altr_a10sr_reg_writeable,
        .volatile_reg = altr_a10sr_reg_volatile,

};

static int altr_a10sr_spi_probe(struct spi_device *spi)
{
        int ret;
        struct altr_a10sr *a10sr;

        a10sr = devm_kzalloc(&spi->dev, sizeof(*a10sr),
                             GFP_KERNEL);
        if (!a10sr)
                return -ENOMEM;

        spi->mode = SPI_MODE_3;
        spi->bits_per_word = 8;
        spi_setup(spi);

        a10sr->dev = &spi->dev;

        spi_set_drvdata(spi, a10sr);

        a10sr->regmap = devm_regmap_init_spi(spi, &altr_a10sr_regmap_config);
        if (IS_ERR(a10sr->regmap)) {
                ret = PTR_ERR(a10sr->regmap);
                dev_err(&spi->dev, "Failed to allocate register map: %d\n",
                        ret);
                return ret;
        }

        ret = devm_mfd_add_devices(a10sr->dev, PLATFORM_DEVID_AUTO,
                                   altr_a10sr_subdev_info,
                                   ARRAY_SIZE(altr_a10sr_subdev_info),
                                   NULL, 0, NULL);
        if (ret)
                dev_err(a10sr->dev, "Failed to register sub-devices: %d\n",
                        ret);

        return ret;
}

static const struct of_device_id altr_a10sr_spi_of_match[] = {
        { .compatible = "altr,a10sr" },
        { },
};
MODULE_DEVICE_TABLE(of, altr_a10sr_spi_of_match);

static const struct spi_device_id altr_a10sr_spi_ids[] = {
        { .name = "a10sr" },
        { },
};
MODULE_DEVICE_TABLE(spi, altr_a10sr_spi_ids);

static struct spi_driver altr_a10sr_spi_driver = {
        .probe = altr_a10sr_spi_probe,
        .driver = {
                .name = "altr_a10sr",
                .of_match_table = altr_a10sr_spi_of_match,
        },
        .id_table = altr_a10sr_spi_ids,
};
builtin_driver(altr_a10sr_spi_driver, spi_register_driver)