// SPDX-License-Identifier: GPL-2.0-only
/*
 * MEN Chameleon Bus.
 *
 * Copyright (C) 2014 MEN Mikroelektronik GmbH (www.men.de)
 * Author: Andreas Werner <andreas.werner@men.de>
 */

#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/dmi.h>
#include <linux/mcb.h>
#include <linux/io.h>
#include "mcb-internal.h"

struct priv {
        struct mcb_bus *bus;
        struct resource *mem;
        void __iomem *base;
};

static int mcb_lpc_probe(struct platform_device *pdev)
{
        struct resource *res;
        struct priv *priv;
        int ret = 0, table_size;

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

        priv->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!priv->mem) {
                dev_err(&pdev->dev, "No Memory resource\n");
                return -ENODEV;
        }

        res = devm_request_mem_region(&pdev->dev, priv->mem->start,
                                      resource_size(priv->mem),
                                      KBUILD_MODNAME);
        if (!res) {
                dev_err(&pdev->dev, "Failed to request IO memory\n");
                return -EBUSY;
        }

        priv->base = devm_ioremap(&pdev->dev, priv->mem->start,
                                  resource_size(priv->mem));
        if (!priv->base) {
                dev_err(&pdev->dev, "Cannot ioremap\n");
                return -ENOMEM;
        }

        platform_set_drvdata(pdev, priv);

        priv->bus = mcb_alloc_bus(&pdev->dev);
        if (IS_ERR(priv->bus))
                return PTR_ERR(priv->bus);

        ret = chameleon_parse_cells(priv->bus, priv->mem->start, priv->base);
        if (ret < 0) {
                goto out_mcb_bus;
        }

        table_size = ret;

        if (table_size < CHAM_HEADER_SIZE) {
                /* Release the previous resources */
                devm_iounmap(&pdev->dev, priv->base);
                devm_release_mem_region(&pdev->dev, priv->mem->start, resource_size(priv->mem));

                /* Then, allocate it again with the actual chameleon table size */
                res = devm_request_mem_region(&pdev->dev, priv->mem->start,
                                              table_size,
                                              KBUILD_MODNAME);
                if (!res) {
                        dev_err(&pdev->dev, "Failed to request PCI memory\n");
                        ret = -EBUSY;
                        goto out_mcb_bus;
                }

                priv->base = devm_ioremap(&pdev->dev, priv->mem->start, table_size);
                if (!priv->base) {
                        dev_err(&pdev->dev, "Cannot ioremap\n");
                        ret = -ENOMEM;
                        goto out_mcb_bus;
                }

                platform_set_drvdata(pdev, priv);
        }

        mcb_bus_add_devices(priv->bus);

        return 0;

out_mcb_bus:
        mcb_release_bus(priv->bus);
        return ret;
}

static void mcb_lpc_remove(struct platform_device *pdev)
{
        struct priv *priv = platform_get_drvdata(pdev);

        mcb_release_bus(priv->bus);
}

static struct platform_device *mcb_lpc_pdev;

static int mcb_lpc_create_platform_device(const struct dmi_system_id *id)
{
        struct resource *res = id->driver_data;
        int ret;

        mcb_lpc_pdev = platform_device_alloc("mcb-lpc", -1);
        if (!mcb_lpc_pdev)
                return -ENOMEM;

        ret = platform_device_add_resources(mcb_lpc_pdev, res, 1);
        if (ret)
                goto out_put;

        ret = platform_device_add(mcb_lpc_pdev);
        if (ret)
                goto out_put;

        return 0;

out_put:
        platform_device_put(mcb_lpc_pdev);
        return ret;
}

static struct resource sc24_fpga_resource = DEFINE_RES_MEM(0xe000e000, CHAM_HEADER_SIZE);
static struct resource sc31_fpga_resource = DEFINE_RES_MEM(0xf000e000, CHAM_HEADER_SIZE);

static struct platform_driver mcb_lpc_driver = {
        .driver         = {
                .name = "mcb-lpc",
        },
        .probe          = mcb_lpc_probe,
        .remove         = mcb_lpc_remove,
};

static const struct dmi_system_id mcb_lpc_dmi_table[] = {
        {
                .ident = "SC24",
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "MEN"),
                        DMI_MATCH(DMI_PRODUCT_VERSION, "14SC24"),
                },
                .driver_data = (void *)&sc24_fpga_resource,
                .callback = mcb_lpc_create_platform_device,
        },
        {
                .ident = "SC31",
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "MEN"),
                        DMI_MATCH(DMI_PRODUCT_VERSION, "14SC31"),
                },
                .driver_data = (void *)&sc31_fpga_resource,
                .callback = mcb_lpc_create_platform_device,
        },
        {}
};
MODULE_DEVICE_TABLE(dmi, mcb_lpc_dmi_table);

static int __init mcb_lpc_init(void)
{
        if (!dmi_check_system(mcb_lpc_dmi_table))
                return -ENODEV;

        return platform_driver_register(&mcb_lpc_driver);
}

static void __exit mcb_lpc_exit(void)
{
        platform_device_unregister(mcb_lpc_pdev);
        platform_driver_unregister(&mcb_lpc_driver);
}

module_init(mcb_lpc_init);
module_exit(mcb_lpc_exit);

MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MCB over LPC support");
MODULE_IMPORT_NS("MCB");