// SPDX-License-Identifier: GPL-2.0-only
/*
 *  Copyright (c) 2005 Samsung Electronics
 *  Kyungmin Park <kyungmin.park@samsung.com>
 *
 *  Overview:
 *   This is a device driver for the OneNAND flash for generic boards.
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/onenand.h>
#include <linux/mtd/partitions.h>
#include <linux/io.h>

/*
 * Note: Driver name and platform data format have been updated!
 *
 * This version of the driver is named "onenand-flash" and takes struct
 * onenand_platform_data as platform data. The old ARM-specific version
 * with the name "onenand" used to take struct flash_platform_data.
 */
#define DRIVER_NAME     "onenand-flash"

struct onenand_info {
        struct mtd_info         mtd;
        struct onenand_chip     onenand;
};

static int generic_onenand_probe(struct platform_device *pdev)
{
        struct onenand_info *info;
        struct onenand_platform_data *pdata = dev_get_platdata(&pdev->dev);
        struct resource *res = pdev->resource;
        unsigned long size = resource_size(res);
        int err;

        info = kzalloc_obj(struct onenand_info);
        if (!info)
                return -ENOMEM;

        if (!request_mem_region(res->start, size, dev_name(&pdev->dev))) {
                err = -EBUSY;
                goto out_free_info;
        }

        info->onenand.base = ioremap(res->start, size);
        if (!info->onenand.base) {
                err = -ENOMEM;
                goto out_release_mem_region;
        }

        info->onenand.mmcontrol = pdata ? pdata->mmcontrol : NULL;

        err = platform_get_irq(pdev, 0);
        if (err < 0)
                goto out_iounmap;

        info->onenand.irq = err;

        info->mtd.dev.parent = &pdev->dev;
        info->mtd.priv = &info->onenand;

        if (onenand_scan(&info->mtd, 1)) {
                err = -ENXIO;
                goto out_iounmap;
        }

        err = mtd_device_register(&info->mtd, pdata ? pdata->parts : NULL,
                                  pdata ? pdata->nr_parts : 0);

        platform_set_drvdata(pdev, info);

        return 0;

out_iounmap:
        iounmap(info->onenand.base);
out_release_mem_region:
        release_mem_region(res->start, size);
out_free_info:
        kfree(info);

        return err;
}

static void generic_onenand_remove(struct platform_device *pdev)
{
        struct onenand_info *info = platform_get_drvdata(pdev);
        struct resource *res = pdev->resource;
        unsigned long size = resource_size(res);

        if (info) {
                onenand_release(&info->mtd);
                release_mem_region(res->start, size);
                iounmap(info->onenand.base);
                kfree(info);
        }
}

static struct platform_driver generic_onenand_driver = {
        .driver = {
                .name           = DRIVER_NAME,
        },
        .probe          = generic_onenand_probe,
        .remove         = generic_onenand_remove,
};

module_platform_driver(generic_onenand_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Kyungmin Park <kyungmin.park@samsung.com>");
MODULE_DESCRIPTION("Glue layer for OneNAND flash on generic boards");
MODULE_ALIAS("platform:" DRIVER_NAME);