Re: [PATCH 2/2] mtd: spinand: winbond: add Winbond W25N02KV flash support

[Frieder Schrempf <frieder.schrempf@kontron.de>]

On 07.10.22 12:48, mikhail.kshevetskiy@iopsys.eu wrote:
> From: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>

Even if the subject line already describes the change, you should
probably add a short sentence here so the body of the commit message
isn't empty.

> Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>
> ---
>  drivers/mtd/nand/spi/winbond.c | 75 ++++++++++++++++++++++++++++++++++
>  1 file changed, 75 insertions(+)
> 
> diff --git a/drivers/mtd/nand/spi/winbond.c b/drivers/mtd/nand/spi/winbond.c
> index ed368a55d68f..3ad58cd284d8 100644
> --- a/drivers/mtd/nand/spi/winbond.c
> +++ b/drivers/mtd/nand/spi/winbond.c
> @@ -74,6 +74,72 @@ static int w25m02gv_select_target(struct spinand_device *spinand,
>  	return spi_mem_exec_op(spinand->spimem, &op);
>  }
>  
> +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 w25n02kv_ooblayout = {
> +	.ecc = w25n02kv_ooblayout_ecc,
> +	.free = w25n02kv_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_GET_FEATURE_OP(0x30, &mbf);
> +
> +	switch (status & STATUS_ECC_MASK) {
> +	case STATUS_ECC_NO_BITFLIPS:
> +		return 0;
> +
> +	case STATUS_ECC_UNCOR_ERROR:
> +		return -EBADMSG;
> +
> +	case STATUS_ECC_HAS_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 >>= 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 const struct spinand_info winbond_spinand_table[] = {
>  	SPINAND_INFO("W25M02GV",
>  		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0xab, 0x21),
> @@ -94,6 +160,15 @@ static const struct spinand_info winbond_spinand_table[] = {
>  					      &update_cache_variants),
>  		     0,
>  		     SPINAND_ECCINFO(&w25m02gv_ooblayout, NULL)),
> +	SPINAND_INFO("W25N02KV",
> +		     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)),
>  };
>  
>  static int winbond_spinand_init(struct spinand_device *spinand)