// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2017 exceet electronics GmbH
 *
 * Authors:
 *      Frieder Schrempf <frieder.schrempf@exceet.de>
 *      Boris Brezillon <boris.brezillon@bootlin.com>
 */

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

#define SPINAND_MFR_WINBOND             0xEF

#define WINBOND_CFG_HFREQ               BIT(0)
#define WINBOND_CFG_BUF_READ            BIT(3)

#define W25N04KV_STATUS_ECC_5_8_BITFLIPS        (3 << 4)
#define W25W35NXXJW_STATUS_ECC_MULT_UNCOR       (3 << 4)

#define W25N0XJW_SR4                    0xD0
#define W25N0XJW_SR4_HS                 BIT(2)

#define W35N01JW_VCR_IO_MODE_REG        0x00
#define W35N01JW_VCR_IO_MODE_SINGLE_SDR         0xFF
#define W35N01JW_VCR_IO_MODE_OCTAL_SDR          0xDF
#define W35N01JW_VCR_IO_MODE_OCTAL_DDR_DS       0xE7
#define W35N01JW_VCR_IO_MODE_OCTAL_DDR          0xC7
#define W35N01JW_VCR_DUMMY_CLOCK_REG    0x01

/*
 * Winbond chips ignore the address bytes during continuous reads, and
 * because the dummy cycles are enough they indicate dropping the
 * address cycles from the continuous read from cache variants. This is
 * very poorly supported by SPI controller drivers which are "wired" to
 * always at least provide the column. Keep using address cycles, but
 * reduce the number of dummy cycles accordingly.
 */
#define WINBOND_CONT_READ_FROM_CACHE_FAST_1S_1S_1S_OP(ndummy, buf, len, freq) \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0x0b, 1),                             \
                   SPI_MEM_OP_ADDR(1, 0, 1),                            \
                   SPI_MEM_OP_DUMMY(ndummy - 1, 1),                     \
                   SPI_MEM_OP_DATA_IN(len, buf, 1),                     \
                   SPI_MEM_OP_MAX_FREQ(freq))

#define WINBOND_CONT_READ_FROM_CACHE_1S_1D_1D_OP(ndummy, buf, len, freq) \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0x0d, 1),                             \
                   SPI_MEM_DTR_OP_ADDR(2, 0, 1),                        \
                   SPI_MEM_DTR_OP_DUMMY(ndummy, 1),                     \
                   SPI_MEM_DTR_OP_DATA_IN(len, buf, 1),                 \
                   SPI_MEM_OP_MAX_FREQ(freq))

#define WINBOND_CONT_READ_FROM_CACHE_1S_1S_2S_OP(ndummy, buf, len, freq) \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0x3b, 1),                             \
                   SPI_MEM_OP_ADDR(1, 0, 1),                            \
                   SPI_MEM_OP_DUMMY(ndummy - 1, 1),                     \
                   SPI_MEM_OP_DATA_IN(len, buf, 2),                     \
                   SPI_MEM_OP_MAX_FREQ(freq))

#define WINBOND_CONT_READ_FROM_CACHE_1S_2S_2S_OP(ndummy, buf, len, freq) \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0xbb, 1),                             \
                   SPI_MEM_OP_ADDR(1, 0, 2),                            \
                   SPI_MEM_OP_DUMMY(ndummy - 1, 2),                     \
                   SPI_MEM_OP_DATA_IN(len, buf, 2),                     \
                   SPI_MEM_OP_MAX_FREQ(freq))

#define WINBOND_CONT_READ_FROM_CACHE_1S_2D_2D_OP(ndummy, buf, len, freq) \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0xbd, 1),                             \
                   SPI_MEM_DTR_OP_ADDR(1, 0, 2),                        \
                   SPI_MEM_DTR_OP_DUMMY(ndummy - 1, 2),                 \
                   SPI_MEM_DTR_OP_DATA_IN(len, buf, 2),                 \
                   SPI_MEM_OP_MAX_FREQ(freq))

#define WINBOND_CONT_READ_FROM_CACHE_1S_1S_4S_OP(ndummy, buf, len, freq) \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0x6b, 1),                             \
                   SPI_MEM_OP_ADDR(1, 0, 1),                            \
                   SPI_MEM_OP_DUMMY(ndummy - 1, 1),                     \
                   SPI_MEM_OP_DATA_IN(len, buf, 4),                     \
                   SPI_MEM_OP_MAX_FREQ(freq))

#define WINBOND_CONT_READ_FROM_CACHE_1S_1D_4D_OP(ndummy, buf, len, freq) \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0x6d, 1),                             \
                   SPI_MEM_DTR_OP_ADDR(1, 0, 1),                        \
                   SPI_MEM_DTR_OP_DUMMY(ndummy - 1, 1),                 \
                   SPI_MEM_DTR_OP_DATA_IN(len, buf, 4),                 \
                   SPI_MEM_OP_MAX_FREQ(freq))

#define WINBOND_CONT_READ_FROM_CACHE_1S_4S_4S_OP(ndummy, buf, len, freq) \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0xeb, 1),                             \
                   SPI_MEM_OP_ADDR(1, 0, 4),                            \
                   SPI_MEM_OP_DUMMY(ndummy - 1, 4),                     \
                   SPI_MEM_OP_DATA_IN(len, buf, 4),                     \
                   SPI_MEM_OP_MAX_FREQ(freq))

#define WINBOND_CONT_READ_FROM_CACHE_1S_4D_4D_OP(ndummy, buf, len, freq) \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0xed, 1),                             \
                   SPI_MEM_DTR_OP_ADDR(1, 0, 4),                        \
                   SPI_MEM_DTR_OP_DUMMY(ndummy - 1, 4),                 \
                   SPI_MEM_DTR_OP_DATA_IN(len, buf, 4),                 \
                   SPI_MEM_OP_MAX_FREQ(freq))

#define WINBOND_CONT_READ_FROM_CACHE_1S_1S_8S_OP(ndummy, buf, len, freq) \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0x8b, 1),                             \
                   SPI_MEM_OP_ADDR(1, 0, 1),                            \
                   SPI_MEM_OP_DUMMY(ndummy - 1, 1),                     \
                   SPI_MEM_OP_DATA_IN(len, buf, 8),                     \
                   SPI_MEM_OP_MAX_FREQ(freq))

#define WINBOND_CONT_READ_FROM_CACHE_1S_1D_8D_OP(ndummy, buf, len, freq) \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0x9d, 1),                             \
                   SPI_MEM_DTR_OP_ADDR(1, 0, 1),                        \
                   SPI_MEM_DTR_OP_DUMMY(ndummy - 1, 1),                 \
                   SPI_MEM_DTR_OP_DATA_IN(len, buf, 8),                 \
                   SPI_MEM_OP_MAX_FREQ(freq))

#define WINBOND_CONT_READ_FROM_CACHE_1S_8S_8S_OP(ndummy, buf, len, freq) \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0xcb, 1),                             \
                   SPI_MEM_OP_ADDR(1, 0, 8),                            \
                   SPI_MEM_OP_DUMMY(ndummy - 1, 8),                     \
                   SPI_MEM_OP_DATA_IN(len, buf, 8),                     \
                   SPI_MEM_OP_MAX_FREQ(freq))

#define WINBOND_CONT_READ_FROM_CACHE_8D_8D_8D_OP(ndummy, buf, len, freq) \
        SPI_MEM_OP(SPI_MEM_DTR_OP_RPT_CMD(0x9d, 8),                     \
                   SPI_MEM_DTR_OP_ADDR(2, 0, 8),                        \
                   SPI_MEM_DTR_OP_DUMMY(ndummy - 2, 8),                 \
                   SPI_MEM_DTR_OP_DATA_IN(len, buf, 8),                 \
                   SPI_MEM_OP_MAX_FREQ(freq))

/*
 * "X2" in the core is equivalent to "dual output" in the datasheets,
 * "X4" in the core is equivalent to "quad output" in the datasheets.
 * Quad and octal capable chips feature an absolute maximum frequency of 166MHz.
 */

static SPINAND_OP_VARIANTS(read_cache_octal_variants,
                SPINAND_PAGE_READ_FROM_CACHE_8D_8D_8D_OP(0, 24, NULL, 0, 120 * HZ_PER_MHZ),
                SPINAND_PAGE_READ_FROM_CACHE_8D_8D_8D_OP(0, 16, NULL, 0, 86 * HZ_PER_MHZ),
                SPINAND_PAGE_READ_FROM_CACHE_1S_1D_8D_OP(0, 3, NULL, 0, 120 * HZ_PER_MHZ),
                SPINAND_PAGE_READ_FROM_CACHE_1S_1D_8D_OP(0, 2, NULL, 0, 105 * HZ_PER_MHZ),
                SPINAND_PAGE_READ_FROM_CACHE_1S_8S_8S_OP(0, 20, NULL, 0, 0),
                SPINAND_PAGE_READ_FROM_CACHE_1S_8S_8S_OP(0, 16, NULL, 0, 162 * HZ_PER_MHZ),
                SPINAND_PAGE_READ_FROM_CACHE_1S_8S_8S_OP(0, 12, NULL, 0, 124 * HZ_PER_MHZ),
                SPINAND_PAGE_READ_FROM_CACHE_1S_8S_8S_OP(0, 8, NULL, 0, 86 * HZ_PER_MHZ),
                SPINAND_PAGE_READ_FROM_CACHE_1S_1S_8S_OP(0, 2, NULL, 0, 0),
                SPINAND_PAGE_READ_FROM_CACHE_1S_1S_8S_OP(0, 1, NULL, 0, 133 * HZ_PER_MHZ),
                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(cont_read_cache_octal_variants,
                WINBOND_CONT_READ_FROM_CACHE_8D_8D_8D_OP(24, NULL, 0, 120 * HZ_PER_MHZ),
                WINBOND_CONT_READ_FROM_CACHE_8D_8D_8D_OP(16, NULL, 0, 86 * HZ_PER_MHZ),
                WINBOND_CONT_READ_FROM_CACHE_1S_1D_8D_OP(3, NULL, 0, 120 * HZ_PER_MHZ),
                WINBOND_CONT_READ_FROM_CACHE_1S_1D_8D_OP(2, NULL, 0, 105 * HZ_PER_MHZ),
                WINBOND_CONT_READ_FROM_CACHE_1S_8S_8S_OP(20, NULL, 0, 0),
                WINBOND_CONT_READ_FROM_CACHE_1S_8S_8S_OP(16, NULL, 0, 162 * HZ_PER_MHZ),
                WINBOND_CONT_READ_FROM_CACHE_1S_8S_8S_OP(12, NULL, 0, 124 * HZ_PER_MHZ),
                WINBOND_CONT_READ_FROM_CACHE_1S_8S_8S_OP(8, NULL, 0, 86 * HZ_PER_MHZ),
                WINBOND_CONT_READ_FROM_CACHE_1S_1S_8S_OP(2, NULL, 0, 0),
                WINBOND_CONT_READ_FROM_CACHE_1S_1S_8S_OP(1, NULL, 0, 133 * HZ_PER_MHZ),
                WINBOND_CONT_READ_FROM_CACHE_FAST_1S_1S_1S_OP(1, NULL, 0, 0));

static SPINAND_OP_VARIANTS(write_cache_octal_variants,
                SPINAND_PROG_LOAD_8D_8D_8D_OP(true, 0, NULL, 0),
                SPINAND_PROG_LOAD_1S_8S_8S_OP(true, 0, NULL, 0),
                SPINAND_PROG_LOAD_1S_1S_8S_OP(0, NULL, 0),
                SPINAND_PROG_LOAD_1S_1S_1S_OP(true, 0, NULL, 0));

static SPINAND_OP_VARIANTS(update_cache_octal_variants,
                SPINAND_PROG_LOAD_8D_8D_8D_OP(false, 0, NULL, 0),
                SPINAND_PROG_LOAD_1S_8S_8S_OP(false, 0, NULL, 0),
                SPINAND_PROG_LOAD_1S_1S_1S_OP(false, 0, NULL, 0));

static SPINAND_OP_VARIANTS(read_cache_dual_quad_dtr_variants,
                SPINAND_PAGE_READ_FROM_CACHE_1S_4D_4D_OP(0, 8, NULL, 0, 80 * HZ_PER_MHZ),
                SPINAND_PAGE_READ_FROM_CACHE_1S_1D_4D_OP(0, 2, NULL, 0, 80 * HZ_PER_MHZ),
                SPINAND_PAGE_READ_FROM_CACHE_1S_4S_4S_OP(0, 4, NULL, 0, 0),
                SPINAND_PAGE_READ_FROM_CACHE_1S_4S_4S_OP(0, 2, NULL, 0, 104 * HZ_PER_MHZ),
                SPINAND_PAGE_READ_FROM_CACHE_1S_1S_4S_OP(0, 1, NULL, 0, 0),
                SPINAND_PAGE_READ_FROM_CACHE_1S_2D_2D_OP(0, 4, NULL, 0, 80 * HZ_PER_MHZ),
                SPINAND_PAGE_READ_FROM_CACHE_1S_1D_2D_OP(0, 2, NULL, 0, 80 * HZ_PER_MHZ),
                SPINAND_PAGE_READ_FROM_CACHE_1S_2S_2S_OP(0, 2, NULL, 0, 0),
                SPINAND_PAGE_READ_FROM_CACHE_1S_2S_2S_OP(0, 1, NULL, 0, 104 * HZ_PER_MHZ),
                SPINAND_PAGE_READ_FROM_CACHE_1S_1S_2S_OP(0, 1, NULL, 0, 0),
                SPINAND_PAGE_READ_FROM_CACHE_1S_1D_1D_OP(0, 2, NULL, 0, 80 * HZ_PER_MHZ),
                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, 54 * HZ_PER_MHZ));

static SPINAND_OP_VARIANTS(cont_read_cache_dual_quad_dtr_variants,
                WINBOND_CONT_READ_FROM_CACHE_1S_4D_4D_OP(11, NULL, 0, 80 * HZ_PER_MHZ),
                WINBOND_CONT_READ_FROM_CACHE_1S_1D_4D_OP(5, NULL, 0, 80 * HZ_PER_MHZ),
                WINBOND_CONT_READ_FROM_CACHE_1S_4S_4S_OP(7, NULL, 0, 0),
                WINBOND_CONT_READ_FROM_CACHE_1S_4S_4S_OP(6, NULL, 0, 104 * HZ_PER_MHZ),
                WINBOND_CONT_READ_FROM_CACHE_1S_1S_4S_OP(4, NULL, 0, 0),
                WINBOND_CONT_READ_FROM_CACHE_1S_2D_2D_OP(6, NULL, 0, 80 * HZ_PER_MHZ),
                /* The 1S_1D_2D variant would require 4.5 dummy bytes, this is not possible */
                WINBOND_CONT_READ_FROM_CACHE_1S_2S_2S_OP(5, NULL, 0, 0),
                WINBOND_CONT_READ_FROM_CACHE_1S_2S_2S_OP(4, NULL, 0, 104 * HZ_PER_MHZ),
                WINBOND_CONT_READ_FROM_CACHE_1S_1S_2S_OP(4, NULL, 0, 0),
                /* The 1S_1D_1D variant would require 4.5 dummy bytes, this is not possible */
                WINBOND_CONT_READ_FROM_CACHE_FAST_1S_1S_1S_OP(4, NULL, 0, 0));

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));

#define SPINAND_WINBOND_WRITE_VCR_1S_1S_1S(reg, buf)                    \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0x81, 1),                             \
                   SPI_MEM_OP_ADDR(3, reg, 1),                          \
                   SPI_MEM_OP_NO_DUMMY,                                 \
                   SPI_MEM_OP_DATA_OUT(1, buf, 1))

#define SPINAND_WINBOND_WRITE_VCR_8D_8D_8D(reg, buf)                    \
        SPI_MEM_OP(SPI_MEM_DTR_OP_RPT_CMD(0x81, 8),                     \
                   SPI_MEM_DTR_OP_ADDR(4, reg << 8, 8),                 \
                   SPI_MEM_OP_NO_DUMMY,                                 \
                   SPI_MEM_DTR_OP_DATA_OUT(2, buf, 8))

static SPINAND_OP_VARIANTS(winbond_w35_ops,
                SPINAND_WINBOND_WRITE_VCR_1S_1S_1S(0, NULL),
                SPINAND_WINBOND_WRITE_VCR_8D_8D_8D(0, NULL));

static struct spi_mem_op
spinand_fill_winbond_write_vcr_op(struct spinand_device *spinand, u8 reg, void *valptr)
{
        return (spinand->bus_iface == SSDR) ?
                (struct spi_mem_op)SPINAND_WINBOND_WRITE_VCR_1S_1S_1S(reg, valptr) :
                (struct spi_mem_op)SPINAND_WINBOND_WRITE_VCR_8D_8D_8D(reg, valptr);
}

#define SPINAND_WINBOND_SELECT_TARGET_1S_0_1S(buf)                      \
        SPI_MEM_OP(SPI_MEM_OP_CMD(0xc2, 1),                             \
                   SPI_MEM_OP_NO_ADDR,                                  \
                   SPI_MEM_OP_NO_DUMMY,                                 \
                   SPI_MEM_OP_DATA_OUT(1, buf, 1))

static SPINAND_OP_VARIANTS(winbond_w25_ops,
                SPINAND_WINBOND_SELECT_TARGET_1S_0_1S(NULL));

static struct spi_mem_op
spinand_fill_winbond_select_target_op(struct spinand_device *spinand, void *valptr)
{
        WARN_ON_ONCE(spinand->bus_iface != SSDR);

        return (struct spi_mem_op)SPINAND_WINBOND_SELECT_TARGET_1S_0_1S(valptr);
}

static int w25m02gv_ooblayout_ecc(struct mtd_info *mtd, int section,
                                  struct mtd_oob_region *region)
{
        if (section > 3)
                return -ERANGE;

        region->offset = (16 * section) + 8;
        region->length = 8;

        return 0;
}

static int w25m02gv_ooblayout_free(struct mtd_info *mtd, int section,
                                   struct mtd_oob_region *region)
{
        if (section > 3)
                return -ERANGE;

        region->offset = (16 * section) + 2;
        region->length = 6;

        return 0;
}

static const struct mtd_ooblayout_ops w25m02gv_ooblayout = {
        .ecc = w25m02gv_ooblayout_ecc,
        .free = w25m02gv_ooblayout_free,
};

static int w25m02gv_select_target(struct spinand_device *spinand,
                                  unsigned int target)
{
        struct spi_mem_op op = SPINAND_OP(spinand, winbond_select_target,
                                          spinand->scratchbuf);

        *spinand->scratchbuf = target;
        return spi_mem_exec_op(spinand->spimem, &op);
}

static int w25n01kv_ooblayout_ecc(struct mtd_info *mtd, int section,
                                  struct mtd_oob_region *region)
{
        if (section > 3)
                return -ERANGE;

        region->offset = 64 + (8 * section);
        region->length = 7;

        return 0;
}

static int w25n02kv_ooblayout_ecc(struct mtd_info *mtd, int section,
                                  struct mtd_oob_region *region)
{
        if (section > 3)
                return -ERANGE;

        region->offset = 64 + (16 * section);
        region->length = 13;

        return 0;
}

static int w25n02kv_ooblayout_free(struct mtd_info *mtd, int section,
                                   struct mtd_oob_region *region)
{
        if (section > 3)
                return -ERANGE;

        region->offset = (16 * section) + 2;
        region->length = 14;

        return 0;
}

static const struct mtd_ooblayout_ops w25n01kv_ooblayout = {
        .ecc = w25n01kv_ooblayout_ecc,
        .free = w25n02kv_ooblayout_free,
};

static const struct mtd_ooblayout_ops w25n02kv_ooblayout = {
        .ecc = w25n02kv_ooblayout_ecc,
        .free = w25n02kv_ooblayout_free,
};

static int w25n01jw_ooblayout_ecc(struct mtd_info *mtd, int section,
                                  struct mtd_oob_region *region)
{
        if (section > 3)
                return -ERANGE;

        region->offset = (16 * section) + 12;
        region->length = 4;

        return 0;
}

static int w25n01jw_ooblayout_free(struct mtd_info *mtd, int section,
                                   struct mtd_oob_region *region)
{
        if (section > 3)
                return -ERANGE;

        region->offset = (16 * section);
        region->length = 12;

        /* Extract BBM */
        if (!section) {
                region->offset += 2;
                region->length -= 2;
        }

        return 0;
}

static int w35n01jw_ooblayout_ecc(struct mtd_info *mtd, int section,
                                  struct mtd_oob_region *region)
{
        if (section > 7)
                return -ERANGE;

        region->offset = (16 * section) + 12;
        region->length = 4;

        return 0;
}

static int w35n01jw_ooblayout_free(struct mtd_info *mtd, int section,
                                   struct mtd_oob_region *region)
{
        if (section > 7)
                return -ERANGE;

        region->offset = 16 * section;
        region->length = 12;

        /* Extract BBM */
        if (!section) {
                region->offset += 2;
                region->length -= 2;
        }

        return 0;
}

static const struct mtd_ooblayout_ops w25n01jw_ooblayout = {
        .ecc = w25n01jw_ooblayout_ecc,
        .free = w25n01jw_ooblayout_free,
};

static const struct mtd_ooblayout_ops w35n01jw_ooblayout = {
        .ecc = w35n01jw_ooblayout_ecc,
        .free = w35n01jw_ooblayout_free,
};

static int w25n02kv_ecc_get_status(struct spinand_device *spinand,
                                   u8 status)
{
        struct nand_device *nand = spinand_to_nand(spinand);
        u8 mbf = 0;
        struct spi_mem_op op = SPINAND_OP(spinand, get_feature,
                                          0x30, spinand->scratchbuf);

        switch (status & STATUS_ECC_MASK) {
        case STATUS_ECC_NO_BITFLIPS:
                return 0;

        case STATUS_ECC_UNCOR_ERROR:
                return -EBADMSG;

        case STATUS_ECC_HAS_BITFLIPS:
        case W25N04KV_STATUS_ECC_5_8_BITFLIPS:
                /*
                 * Let's try to retrieve the real maximum number of bitflips
                 * in order to avoid forcing the wear-leveling layer to move
                 * data around if it's not necessary.
                 */
                if (spi_mem_exec_op(spinand->spimem, &op))
                        return nanddev_get_ecc_conf(nand)->strength;

                mbf = *(spinand->scratchbuf) >> 4;

                if (WARN_ON(mbf > nanddev_get_ecc_conf(nand)->strength || !mbf))
                        return nanddev_get_ecc_conf(nand)->strength;

                return mbf;

        default:
                break;
        }

        return -EINVAL;
}

static int w25w35nxxjw_ecc_get_status(struct spinand_device *spinand, u8 status)
{
        switch (status & STATUS_ECC_MASK) {
        case STATUS_ECC_NO_BITFLIPS:
                return 0;

        case STATUS_ECC_HAS_BITFLIPS:
                return 1;

        case STATUS_ECC_UNCOR_ERROR:
        case W25W35NXXJW_STATUS_ECC_MULT_UNCOR:
                return -EBADMSG;

        default:
                break;
        }

        return -EINVAL;
}

static int w25n0xjw_set_sr4_hs(struct spinand_device *spinand, bool enable)
{
        int ret;
        u8 sr4;

        ret = spinand_read_reg_op(spinand, W25N0XJW_SR4, &sr4);
        if (ret)
                return ret;

        if (enable)
                sr4 |= W25N0XJW_SR4_HS;
        else
                sr4 &= ~W25N0XJW_SR4_HS;

        return spinand_write_reg_op(spinand, W25N0XJW_SR4, sr4);
}

/*
 * SDR dual and quad I/O operations over 104MHz require the HS bit to
 * enable a few more dummy cycles.
 */
static bool w25n0xjw_op_needs_hs(const struct spi_mem_op *op)
{
        if (op->cmd.dtr || op->addr.dtr || op->dummy.dtr || op->data.dtr)
                return false;
        else if (op->cmd.buswidth != 1 || op->addr.buswidth == 1)
                return false;
        else if (op->max_freq && op->max_freq <= 104 * HZ_PER_MHZ)
                return false;

        return true;
}

static int w25n0xjw_hs_cfg(struct spinand_device *spinand,
                           enum spinand_bus_interface iface)
{
        const struct spi_mem_op *op;

        if (iface != SSDR)
                return -EOPNOTSUPP;

        /*
         * At this stage, we do not yet know the continuous read template, nor
         * if there is going to be one. Let's assume the continuous read
         * template will be selected with the same heuristics as the buffered
         * read variant, as there cannot be a HS configuration mismatch between
         * them.
         */
        op = spinand->op_templates->read_cache;

        return w25n0xjw_set_sr4_hs(spinand, w25n0xjw_op_needs_hs(op));
}

static int w25n0xjw_set_cont_read(struct spinand_device *spinand, bool enable)
{
        u8 mask = enable ? 0 : WINBOND_CFG_BUF_READ;

        return spinand_upd_cfg(spinand, WINBOND_CFG_BUF_READ, mask);
}

static int w35n0xjw_write_vcr(struct spinand_device *spinand, u8 reg, u8 val)
{
        struct spi_mem_op op = SPINAND_OP(spinand, winbond_write_vcr,
                                          reg, spinand->scratchbuf);
        int ret;

        *spinand->scratchbuf = val;

        ret = spinand_write_enable_op(spinand);
        if (ret)
                return ret;

        ret = spi_mem_exec_op(spinand->spimem, &op);
        if (ret)
                return ret;

        /*
         * Write VCR operation doesn't set the busy bit in SR, which means we
         * cannot perform a status poll. Minimum time of 50ns is needed to
         * complete the write.
         */
        ndelay(50);

        return 0;
}

static int w35n0xjw_vcr_cfg(struct spinand_device *spinand,
                            enum spinand_bus_interface iface)
{
        const struct spi_mem_op *ref_op;
        unsigned int dummy_cycles;
        bool dtr, single;
        u8 io_mode;
        int ret;

        switch (iface) {
        case SSDR:
                ref_op = spinand->ssdr_op_templates.read_cache;
                break;
        case ODTR:
                ref_op = spinand->odtr_op_templates.read_cache;
                break;
        default:
                return -EOPNOTSUPP;
        }

        dummy_cycles = ((ref_op->dummy.nbytes * 8) / ref_op->dummy.buswidth) /
                (ref_op->dummy.dtr ? 2 : 1);
        switch (dummy_cycles) {
        case 8:
        case 12:
        case 16:
        case 20:
        case 24:
        case 28:
                break;
        default:
                return -EINVAL;
        }

        ret = w35n0xjw_write_vcr(spinand, W35N01JW_VCR_DUMMY_CLOCK_REG, dummy_cycles);
        if (ret)
                return ret;

        single = (ref_op->cmd.buswidth == 1 &&
                  ref_op->addr.buswidth == 1 &&
                  ref_op->data.buswidth == 1);
        dtr = (ref_op->cmd.dtr && ref_op->addr.dtr && ref_op->data.dtr);
        if (single && !dtr)
                io_mode = W35N01JW_VCR_IO_MODE_SINGLE_SDR;
        else if (!single && !dtr)
                io_mode = W35N01JW_VCR_IO_MODE_OCTAL_SDR;
        else if (!single && dtr)
                io_mode = W35N01JW_VCR_IO_MODE_OCTAL_DDR;
        else
                return -EINVAL;

        ret = w35n0xjw_write_vcr(spinand, W35N01JW_VCR_IO_MODE_REG, io_mode);
        if (ret)
                return ret;

        return 0;
}

static int w35n0xjw_set_cont_read(struct spinand_device *spinand, bool enable)
{
        const struct spi_mem_op *cont_op = spinand->op_templates->cont_read_cache;
        u8 mask = enable ? 0 : WINBOND_CFG_BUF_READ;

        if (cont_op && enable && spinand_op_is_odtr(cont_op) &&
            cont_op->max_freq >= 90 * HZ_PER_MHZ)
                mask |= WINBOND_CFG_HFREQ;

        return spinand_upd_cfg(spinand, WINBOND_CFG_BUF_READ | WINBOND_CFG_HFREQ, mask);
}

static const struct spinand_info winbond_spinand_table[] = {
        /* 512M-bit densities */
        SPINAND_INFO("W25N512GW", /* 1.8V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xba, 0x20),
                     NAND_MEMORG(1, 2048, 64, 64, 512, 10, 1, 1, 1),
                     NAND_ECCREQ(1, 512),
                     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
                                              &write_cache_variants,
                                              &update_cache_variants),
                     0,
                     SPINAND_ECCINFO(&w25m02gv_ooblayout, NULL)),
        /* 1G-bit densities */
        SPINAND_INFO("W25N01GV", /* 3.3V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xaa, 0x21),
                     NAND_MEMORG(1, 2048, 64, 64, 1024, 20, 1, 1, 1),
                     NAND_ECCREQ(1, 512),
                     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
                                              &write_cache_variants,
                                              &update_cache_variants),
                     0,
                     SPINAND_ECCINFO(&w25m02gv_ooblayout, NULL)),
        SPINAND_INFO("W25N01GW", /* 1.8V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xba, 0x21),
                     NAND_MEMORG(1, 2048, 64, 64, 1024, 20, 1, 1, 1),
                     NAND_ECCREQ(1, 512),
                     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
                                              &write_cache_variants,
                                              &update_cache_variants),
                     0,
                     SPINAND_ECCINFO(&w25m02gv_ooblayout, NULL)),
        SPINAND_INFO("W25N01JW", /* high-speed 1.8V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xbc, 0x21),
                     NAND_MEMORG(1, 2048, 64, 64, 1024, 20, 1, 1, 1),
                     NAND_ECCREQ(1, 512),
                     SPINAND_INFO_OP_VARIANTS_WITH_CONT(&read_cache_dual_quad_dtr_variants,
                                                        &write_cache_variants,
                                                        &update_cache_variants,
                                                        &cont_read_cache_dual_quad_dtr_variants),
                     SPINAND_HAS_QE_BIT,
                     SPINAND_ECCINFO(&w25n01jw_ooblayout, w25w35nxxjw_ecc_get_status),
                     SPINAND_CONFIGURE_CHIP(w25n0xjw_hs_cfg),
                     SPINAND_CONT_READ(w25n0xjw_set_cont_read)),
        SPINAND_INFO("W25N01KV", /* 3.3V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xae, 0x21),
                     NAND_MEMORG(1, 2048, 96, 64, 1024, 20, 1, 1, 1),
                     NAND_ECCREQ(4, 512),
                     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
                                              &write_cache_variants,
                                              &update_cache_variants),
                     0,
                     SPINAND_ECCINFO(&w25n01kv_ooblayout, w25n02kv_ecc_get_status)),
        SPINAND_INFO("W35N01JW", /* 1.8V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xdc, 0x21),
                     NAND_MEMORG(1, 4096, 128, 64, 512, 10, 1, 1, 1),
                     NAND_ECCREQ(1, 512),
                     SPINAND_INFO_OP_VARIANTS_WITH_CONT(&read_cache_octal_variants,
                                                        &write_cache_octal_variants,
                                                        &update_cache_octal_variants,
                                                        &cont_read_cache_octal_variants),
                     0,
                     SPINAND_INFO_VENDOR_OPS(&winbond_w35_ops),
                     SPINAND_ECCINFO(&w35n01jw_ooblayout, w25w35nxxjw_ecc_get_status),
                     SPINAND_CONFIGURE_CHIP(w35n0xjw_vcr_cfg),
                     SPINAND_CONT_READ(w35n0xjw_set_cont_read)),
        /* 2G-bit densities */
        SPINAND_INFO("W25M02GV", /* 2x1G-bit 3.3V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xab, 0x21),
                     NAND_MEMORG(1, 2048, 64, 64, 1024, 20, 1, 1, 2),
                     NAND_ECCREQ(1, 512),
                     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
                                              &write_cache_variants,
                                              &update_cache_variants),
                     0,
                     SPINAND_INFO_VENDOR_OPS(&winbond_w25_ops),
                     SPINAND_ECCINFO(&w25m02gv_ooblayout, NULL),
                     SPINAND_SELECT_TARGET(w25m02gv_select_target)),
        SPINAND_INFO("W25N02JW", /* high-speed 1.8V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xbf, 0x22),
                     NAND_MEMORG(1, 2048, 64, 64, 1024, 20, 1, 2, 1),
                     NAND_ECCREQ(1, 512),
                     SPINAND_INFO_OP_VARIANTS_WITH_CONT(&read_cache_dual_quad_dtr_variants,
                                                        &write_cache_variants,
                                                        &update_cache_variants,
                                                        &cont_read_cache_dual_quad_dtr_variants),
                     SPINAND_HAS_QE_BIT,
                     SPINAND_ECCINFO(&w25m02gv_ooblayout, w25w35nxxjw_ecc_get_status),
                     SPINAND_CONFIGURE_CHIP(w25n0xjw_hs_cfg),
                     SPINAND_CONT_READ(w25n0xjw_set_cont_read)),
        SPINAND_INFO("W25N02KV", /* 3.3V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xaa, 0x22),
                     NAND_MEMORG(1, 2048, 128, 64, 2048, 40, 1, 1, 1),
                     NAND_ECCREQ(8, 512),
                     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
                                              &write_cache_variants,
                                              &update_cache_variants),
                     0,
                     SPINAND_ECCINFO(&w25n02kv_ooblayout, w25n02kv_ecc_get_status)),
        SPINAND_INFO("W25N02KW", /* 1.8V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xba, 0x22),
                     NAND_MEMORG(1, 2048, 128, 64, 2048, 40, 1, 1, 1),
                     NAND_ECCREQ(8, 512),
                     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
                                              &write_cache_variants,
                                              &update_cache_variants),
                     0,
                     SPINAND_ECCINFO(&w25n02kv_ooblayout, w25n02kv_ecc_get_status)),
        SPINAND_INFO("W35N02JW", /* 1.8V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xdf, 0x22),
                     NAND_MEMORG(1, 4096, 128, 64, 512, 10, 1, 2, 1),
                     NAND_ECCREQ(1, 512),
                     SPINAND_INFO_OP_VARIANTS_WITH_CONT(&read_cache_octal_variants,
                                                        &write_cache_octal_variants,
                                                        &update_cache_octal_variants,
                                                        &cont_read_cache_octal_variants),
                     SPINAND_ODTR_PACKED_PAGE_READ,
                     SPINAND_INFO_VENDOR_OPS(&winbond_w35_ops),
                     SPINAND_ECCINFO(&w35n01jw_ooblayout, w25w35nxxjw_ecc_get_status),
                     SPINAND_CONFIGURE_CHIP(w35n0xjw_vcr_cfg),
                     SPINAND_CONT_READ(w35n0xjw_set_cont_read)),
        /* 4G-bit densities */
        SPINAND_INFO("W25N04KV", /* 3.3V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xaa, 0x23),
                     NAND_MEMORG(1, 2048, 128, 64, 4096, 40, 2, 1, 1),
                     NAND_ECCREQ(8, 512),
                     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
                                              &write_cache_variants,
                                              &update_cache_variants),
                     0,
                     SPINAND_ECCINFO(&w25n02kv_ooblayout, w25n02kv_ecc_get_status)),
        SPINAND_INFO("W25N04KW", /* 1.8V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xba, 0x23),
                     NAND_MEMORG(1, 2048, 128, 64, 4096, 40, 1, 1, 1),
                     NAND_ECCREQ(8, 512),
                     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
                                              &write_cache_variants,
                                              &update_cache_variants),
                     0,
                     SPINAND_ECCINFO(&w25n02kv_ooblayout, w25n02kv_ecc_get_status)),
        SPINAND_INFO("W35N04JW", /* 1.8V */
                     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xdf, 0x23),
                     NAND_MEMORG(1, 4096, 128, 64, 512, 10, 1, 4, 1),
                     NAND_ECCREQ(1, 512),
                     SPINAND_INFO_OP_VARIANTS_WITH_CONT(&read_cache_octal_variants,
                                                        &write_cache_octal_variants,
                                                        &update_cache_octal_variants,
                                                        &cont_read_cache_octal_variants),
                     SPINAND_ODTR_PACKED_PAGE_READ,
                     SPINAND_INFO_VENDOR_OPS(&winbond_w35_ops),
                     SPINAND_ECCINFO(&w35n01jw_ooblayout, w25w35nxxjw_ecc_get_status),
                     SPINAND_CONFIGURE_CHIP(w35n0xjw_vcr_cfg),
                     SPINAND_CONT_READ(w35n0xjw_set_cont_read)),
};

static int winbond_spinand_init(struct spinand_device *spinand)
{
        struct nand_device *nand = spinand_to_nand(spinand);
        unsigned int i;

        /*
         * Make sure all dies are in buffer read mode and not continuous read
         * mode.
         */
        for (i = 0; i < nand->memorg.ntargets; i++) {
                spinand_select_target(spinand, i);
                spinand_upd_cfg(spinand, WINBOND_CFG_BUF_READ,
                                WINBOND_CFG_BUF_READ);
        }

        return 0;
}

static const struct spinand_manufacturer_ops winbond_spinand_manuf_ops = {
        .init = winbond_spinand_init,
};

const struct spinand_manufacturer winbond_spinand_manufacturer = {
        .id = SPINAND_MFR_WINBOND,
        .name = "Winbond",
        .chips = winbond_spinand_table,
        .nchips = ARRAY_SIZE(winbond_spinand_table),
        .ops = &winbond_spinand_manuf_ops,
};