// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2019 Jeff Kletsky
 *
 * Author: Jeff Kletsky <git-commits@allycomm.com>
 */

#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/mtd/spinand.h>


#define SPINAND_MFR_PARAGON     0xa1


#define PN26G0XA_STATUS_ECC_BITMASK             (3 << 4)

#define PN26G0XA_STATUS_ECC_NONE_DETECTED       (0 << 4)
#define PN26G0XA_STATUS_ECC_1_7_CORRECTED       (1 << 4)
#define PN26G0XA_STATUS_ECC_ERRORED             (2 << 4)
#define PN26G0XA_STATUS_ECC_8_CORRECTED         (3 << 4)


static SPINAND_OP_VARIANTS(read_cache_variants,
                SPINAND_PAGE_READ_FROM_CACHE_1S_4S_4S_OP(0, 2, NULL, 0, 0),
                SPINAND_PAGE_READ_FROM_CACHE_1S_1S_4S_OP(0, 1, NULL, 0, 0),
                SPINAND_PAGE_READ_FROM_CACHE_1S_2S_2S_OP(0, 1, NULL, 0, 0),
                SPINAND_PAGE_READ_FROM_CACHE_1S_1S_2S_OP(0, 1, NULL, 0, 0),
                SPINAND_PAGE_READ_FROM_CACHE_FAST_1S_1S_1S_OP(0, 1, NULL, 0, 0),
                SPINAND_PAGE_READ_FROM_CACHE_1S_1S_1S_OP(0, 1, NULL, 0, 0));

static SPINAND_OP_VARIANTS(write_cache_variants,
                SPINAND_PROG_LOAD_1S_1S_4S_OP(true, 0, NULL, 0),
                SPINAND_PROG_LOAD_1S_1S_1S_OP(true, 0, NULL, 0));

static SPINAND_OP_VARIANTS(update_cache_variants,
                SPINAND_PROG_LOAD_1S_1S_4S_OP(false, 0, NULL, 0),
                SPINAND_PROG_LOAD_1S_1S_1S_OP(false, 0, NULL, 0));


static int pn26g0xa_ooblayout_ecc(struct mtd_info *mtd, int section,
                                   struct mtd_oob_region *region)
{
        if (section > 3)
                return -ERANGE;

        region->offset = 6 + (15 * section); /* 4 BBM + 2 user bytes */
        region->length = 13;

        return 0;
}

static int pn26g0xa_ooblayout_free(struct mtd_info *mtd, int section,
                                   struct mtd_oob_region *region)
{
        if (section > 4)
                return -ERANGE;

        if (section == 4) {
                region->offset = 64;
                region->length = 64;
        } else {
                region->offset = 4 + (15 * section);
                region->length = 2;
        }

        return 0;
}

static int pn26g0xa_ecc_get_status(struct spinand_device *spinand,
                                   u8 status)
{
        switch (status & PN26G0XA_STATUS_ECC_BITMASK) {
        case PN26G0XA_STATUS_ECC_NONE_DETECTED:
                return 0;

        case PN26G0XA_STATUS_ECC_1_7_CORRECTED:
                return 7;       /* Return upper limit by convention */

        case PN26G0XA_STATUS_ECC_8_CORRECTED:
                return 8;

        case PN26G0XA_STATUS_ECC_ERRORED:
                return -EBADMSG;

        default:
                break;
        }

        return -EINVAL;
}

static const struct mtd_ooblayout_ops pn26g0xa_ooblayout = {
        .ecc = pn26g0xa_ooblayout_ecc,
        .free = pn26g0xa_ooblayout_free,
};


static const struct spinand_info paragon_spinand_table[] = {
        SPINAND_INFO("PN26G01A",
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xe1),
                     NAND_MEMORG(1, 2048, 128, 64, 1024, 21, 1, 1, 1),
                     NAND_ECCREQ(8, 512),
                     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
                                              &write_cache_variants,
                                              &update_cache_variants),
                     0,
                     SPINAND_ECCINFO(&pn26g0xa_ooblayout,
                                     pn26g0xa_ecc_get_status)),
        SPINAND_INFO("PN26G02A",
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xe2),
                     NAND_MEMORG(1, 2048, 128, 64, 2048, 41, 1, 1, 1),
                     NAND_ECCREQ(8, 512),
                     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
                                              &write_cache_variants,
                                              &update_cache_variants),
                     0,
                     SPINAND_ECCINFO(&pn26g0xa_ooblayout,
                                     pn26g0xa_ecc_get_status)),
};

static const struct spinand_manufacturer_ops paragon_spinand_manuf_ops = {
};

const struct spinand_manufacturer paragon_spinand_manufacturer = {
        .id = SPINAND_MFR_PARAGON,
        .name = "Paragon",
        .chips = paragon_spinand_table,
        .nchips = ARRAY_SIZE(paragon_spinand_table),
        .ops = &paragon_spinand_manuf_ops,
};