// SPDX-License-Identifier: GPL-2.0-only
/*
 * sl28cpld interrupt controller driver
 *
 * Copyright 2020 Kontron Europe GmbH
 */

#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/regmap.h>

#define INTC_IE 0x00
#define INTC_IP 0x01

static const struct regmap_irq sl28cpld_irqs[] = {
        REGMAP_IRQ_REG_LINE(0, 8),
        REGMAP_IRQ_REG_LINE(1, 8),
        REGMAP_IRQ_REG_LINE(2, 8),
        REGMAP_IRQ_REG_LINE(3, 8),
        REGMAP_IRQ_REG_LINE(4, 8),
        REGMAP_IRQ_REG_LINE(5, 8),
        REGMAP_IRQ_REG_LINE(6, 8),
        REGMAP_IRQ_REG_LINE(7, 8),
};

struct sl28cpld_intc {
        struct regmap *regmap;
        struct regmap_irq_chip chip;
        struct regmap_irq_chip_data *irq_data;
};

static int sl28cpld_intc_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct sl28cpld_intc *irqchip;
        int irq;
        u32 base;
        int ret;

        if (!dev->parent)
                return -ENODEV;

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

        irqchip->regmap = dev_get_regmap(dev->parent, NULL);
        if (!irqchip->regmap)
                return -ENODEV;

        irq = platform_get_irq(pdev, 0);
        if (irq < 0)
                return irq;

        ret = device_property_read_u32(&pdev->dev, "reg", &base);
        if (ret)
                return -EINVAL;

        irqchip->chip.name = "sl28cpld-intc";
        irqchip->chip.irqs = sl28cpld_irqs;
        irqchip->chip.num_irqs = ARRAY_SIZE(sl28cpld_irqs);
        irqchip->chip.num_regs = 1;
        irqchip->chip.status_base = base + INTC_IP;
        irqchip->chip.unmask_base = base + INTC_IE;
        irqchip->chip.ack_base = base + INTC_IP;

        return devm_regmap_add_irq_chip_fwnode(dev, dev_fwnode(dev),
                                               irqchip->regmap, irq,
                                               IRQF_SHARED | IRQF_ONESHOT, 0,
                                               &irqchip->chip,
                                               &irqchip->irq_data);
}

static const struct of_device_id sl28cpld_intc_of_match[] = {
        { .compatible = "kontron,sl28cpld-intc" },
        {}
};
MODULE_DEVICE_TABLE(of, sl28cpld_intc_of_match);

static struct platform_driver sl28cpld_intc_driver = {
        .probe = sl28cpld_intc_probe,
        .driver = {
                .name = "sl28cpld-intc",
                .of_match_table = sl28cpld_intc_of_match,
        }
};
module_platform_driver(sl28cpld_intc_driver);

MODULE_DESCRIPTION("sl28cpld Interrupt Controller Driver");
MODULE_AUTHOR("Michael Walle <michael@walle.cc>");