// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright © 2009 - Maxim Levitsky
 * Common routines & support for xD format
 */
#include <linux/kernel.h>
#include <linux/mtd/rawnand.h>
#include <linux/module.h>
#include <linux/sizes.h>
#include "sm_common.h"

static int oob_sm_ooblayout_ecc(struct mtd_info *mtd, int section,
                                struct mtd_oob_region *oobregion)
{
        if (section > 1)
                return -ERANGE;

        oobregion->length = 3;
        oobregion->offset = ((section + 1) * 8) - 3;

        return 0;
}

static int oob_sm_ooblayout_free(struct mtd_info *mtd, int section,
                                 struct mtd_oob_region *oobregion)
{
        switch (section) {
        case 0:
                /* reserved */
                oobregion->offset = 0;
                oobregion->length = 4;
                break;
        case 1:
                /* LBA1 */
                oobregion->offset = 6;
                oobregion->length = 2;
                break;
        case 2:
                /* LBA2 */
                oobregion->offset = 11;
                oobregion->length = 2;
                break;
        default:
                return -ERANGE;
        }

        return 0;
}

static const struct mtd_ooblayout_ops oob_sm_ops = {
        .ecc = oob_sm_ooblayout_ecc,
        .free = oob_sm_ooblayout_free,
};

/* NOTE: This layout is not compatible with SmartMedia, */
/* because the 256 byte devices have page dependent oob layout */
/* However it does preserve the bad block markers */
/* If you use smftl, it will bypass this and work correctly */
/* If you not, then you break SmartMedia compliance anyway */

static int oob_sm_small_ooblayout_ecc(struct mtd_info *mtd, int section,
                                      struct mtd_oob_region *oobregion)
{
        if (section)
                return -ERANGE;

        oobregion->length = 3;
        oobregion->offset = 0;

        return 0;
}

static int oob_sm_small_ooblayout_free(struct mtd_info *mtd, int section,
                                       struct mtd_oob_region *oobregion)
{
        switch (section) {
        case 0:
                /* reserved */
                oobregion->offset = 3;
                oobregion->length = 2;
                break;
        case 1:
                /* LBA1 */
                oobregion->offset = 6;
                oobregion->length = 2;
                break;
        default:
                return -ERANGE;
        }

        return 0;
}

static const struct mtd_ooblayout_ops oob_sm_small_ops = {
        .ecc = oob_sm_small_ooblayout_ecc,
        .free = oob_sm_small_ooblayout_free,
};

static int sm_block_markbad(struct nand_chip *chip, loff_t ofs)
{
        struct mtd_info *mtd = nand_to_mtd(chip);
        struct mtd_oob_ops ops = { };
        struct sm_oob oob;
        int ret;

        memset(&oob, -1, SM_OOB_SIZE);
        oob.block_status = 0x0F;

        /* As long as this function is called on erase block boundaries
                it will work correctly for 256 byte nand */
        ops.mode = MTD_OPS_PLACE_OOB;
        ops.ooboffs = 0;
        ops.ooblen = mtd->oobsize;
        ops.oobbuf = (void *)&oob;
        ops.datbuf = NULL;


        ret = mtd_write_oob(mtd, ofs, &ops);
        if (ret < 0 || ops.oobretlen != SM_OOB_SIZE) {
                pr_notice("sm_common: can't mark sector at %i as bad\n",
                          (int)ofs);
                return -EIO;
        }

        return 0;
}

static struct nand_flash_dev nand_smartmedia_flash_ids[] = {
        LEGACY_ID_NAND("SmartMedia 2MiB 3,3V ROM",   0x5d, 2,   SZ_8K, NAND_ROM),
        LEGACY_ID_NAND("SmartMedia 4MiB 3,3V",       0xe3, 4,   SZ_8K, 0),
        LEGACY_ID_NAND("SmartMedia 4MiB 3,3/5V",     0xe5, 4,   SZ_8K, 0),
        LEGACY_ID_NAND("SmartMedia 4MiB 5V",         0x6b, 4,   SZ_8K, 0),
        LEGACY_ID_NAND("SmartMedia 4MiB 3,3V ROM",   0xd5, 4,   SZ_8K, NAND_ROM),
        LEGACY_ID_NAND("SmartMedia 8MiB 3,3V",       0xe6, 8,   SZ_8K, 0),
        LEGACY_ID_NAND("SmartMedia 8MiB 3,3V ROM",   0xd6, 8,   SZ_8K, NAND_ROM),
        LEGACY_ID_NAND("SmartMedia 16MiB 3,3V",      0x73, 16,  SZ_16K, 0),
        LEGACY_ID_NAND("SmartMedia 16MiB 3,3V ROM",  0x57, 16,  SZ_16K, NAND_ROM),
        LEGACY_ID_NAND("SmartMedia 32MiB 3,3V",      0x75, 32,  SZ_16K, 0),
        LEGACY_ID_NAND("SmartMedia 32MiB 3,3V ROM",  0x58, 32,  SZ_16K, NAND_ROM),
        LEGACY_ID_NAND("SmartMedia 64MiB 3,3V",      0x76, 64,  SZ_16K, 0),
        LEGACY_ID_NAND("SmartMedia 64MiB 3,3V ROM",  0xd9, 64,  SZ_16K, NAND_ROM),
        LEGACY_ID_NAND("SmartMedia 128MiB 3,3V",     0x79, 128, SZ_16K, 0),
        LEGACY_ID_NAND("SmartMedia 128MiB 3,3V ROM", 0xda, 128, SZ_16K, NAND_ROM),
        LEGACY_ID_NAND("SmartMedia 256MiB 3, 3V",    0x71, 256, SZ_16K, 0),
        LEGACY_ID_NAND("SmartMedia 256MiB 3,3V ROM", 0x5b, 256, SZ_16K, NAND_ROM),
        {NULL}
};

static struct nand_flash_dev nand_xd_flash_ids[] = {
        LEGACY_ID_NAND("xD 16MiB 3,3V",  0x73, 16,   SZ_16K, 0),
        LEGACY_ID_NAND("xD 32MiB 3,3V",  0x75, 32,   SZ_16K, 0),
        LEGACY_ID_NAND("xD 64MiB 3,3V",  0x76, 64,   SZ_16K, 0),
        LEGACY_ID_NAND("xD 128MiB 3,3V", 0x79, 128,  SZ_16K, 0),
        LEGACY_ID_NAND("xD 256MiB 3,3V", 0x71, 256,  SZ_16K, NAND_BROKEN_XD),
        LEGACY_ID_NAND("xD 512MiB 3,3V", 0xdc, 512,  SZ_16K, NAND_BROKEN_XD),
        LEGACY_ID_NAND("xD 1GiB 3,3V",   0xd3, 1024, SZ_16K, NAND_BROKEN_XD),
        LEGACY_ID_NAND("xD 2GiB 3,3V",   0xd5, 2048, SZ_16K, NAND_BROKEN_XD),
        {NULL}
};

static int sm_attach_chip(struct nand_chip *chip)
{
        struct mtd_info *mtd = nand_to_mtd(chip);

        /* Bad block marker position */
        chip->badblockpos = 0x05;
        chip->badblockbits = 7;
        chip->legacy.block_markbad = sm_block_markbad;

        /* ECC layout */
        if (mtd->writesize == SM_SECTOR_SIZE)
                mtd_set_ooblayout(mtd, &oob_sm_ops);
        else if (mtd->writesize == SM_SMALL_PAGE)
                mtd_set_ooblayout(mtd, &oob_sm_small_ops);
        else
                return -ENODEV;

        return 0;
}

static const struct nand_controller_ops sm_controller_ops = {
        .attach_chip = sm_attach_chip,
};

int sm_register_device(struct mtd_info *mtd, int smartmedia)
{
        struct nand_chip *chip = mtd_to_nand(mtd);
        struct nand_flash_dev *flash_ids;
        int ret;

        chip->options |= NAND_SKIP_BBTSCAN;

        /* Scan for card properties */
        chip->legacy.dummy_controller.ops = &sm_controller_ops;
        flash_ids = smartmedia ? nand_smartmedia_flash_ids : nand_xd_flash_ids;
        ret = nand_scan_with_ids(chip, 1, flash_ids);
        if (ret)
                return ret;

        ret = mtd_device_register(mtd, NULL, 0);
        if (ret)
                nand_cleanup(chip);

        return ret;
}
EXPORT_SYMBOL_GPL(sm_register_device);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
MODULE_DESCRIPTION("Common SmartMedia/xD functions");