// SPDX-License-Identifier: GPL-2.0-only OR BSD-3-Clause

/*
 *  Copyright (c) 2022 NVIDIA CORPORATION & AFFILIATES.
 */

#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/devm-helpers.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/reboot.h>
#include <linux/types.h>

struct pwr_mlxbf {
        struct work_struct reboot_work;
        const char *hid;
};

static void pwr_mlxbf_reboot_work(struct work_struct *work)
{
        acpi_bus_generate_netlink_event("button/reboot.*", "Reboot Button", 0x80, 1);
}

static irqreturn_t pwr_mlxbf_irq(int irq, void *ptr)
{
        const char *rst_pwr_hid = "MLNXBF24";
        const char *shutdown_hid = "MLNXBF29";
        struct pwr_mlxbf *priv = ptr;

        if (!strncmp(priv->hid, rst_pwr_hid, 8))
                schedule_work(&priv->reboot_work);

        if (!strncmp(priv->hid, shutdown_hid, 8))
                orderly_poweroff(true);

        return IRQ_HANDLED;
}

static int pwr_mlxbf_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct acpi_device *adev;
        struct pwr_mlxbf *priv;
        const char *hid;
        int irq, err;

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

        adev = ACPI_COMPANION(dev);
        if (!adev)
                return -ENXIO;

        hid = acpi_device_hid(adev);
        priv->hid = hid;

        irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0);
        if (irq < 0)
                return dev_err_probe(dev, irq, "Error getting %s irq.\n", priv->hid);

        err = devm_work_autocancel(dev, &priv->reboot_work, pwr_mlxbf_reboot_work);
        if (err)
                return err;

        err = devm_request_irq(dev, irq, pwr_mlxbf_irq, 0, hid, priv);
        if (err)
                dev_err(dev, "Failed request of %s irq\n", priv->hid);

        return err;
}

static const struct acpi_device_id __maybe_unused pwr_mlxbf_acpi_match[] = {
        { "MLNXBF24", 0 },
        { "MLNXBF29", 0 },
        {},
};
MODULE_DEVICE_TABLE(acpi, pwr_mlxbf_acpi_match);

static struct platform_driver pwr_mlxbf_driver = {
        .driver = {
                .name = "pwr_mlxbf",
                .acpi_match_table = pwr_mlxbf_acpi_match,
        },
        .probe    = pwr_mlxbf_probe,
};

module_platform_driver(pwr_mlxbf_driver);

MODULE_DESCRIPTION("Mellanox BlueField power driver");
MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>");
MODULE_LICENSE("Dual BSD/GPL");