[PATCH] mtd: spi-nor: Set address mode in SEMPER flash when SFDP is skipped

[Tudor Ambarus]

Hi, Takahiro,

On 10/20/25 8:25 AM, tkuw584924 at gmail.com wrote:
> From: Takahiro Kuwano <Takahiro.Kuwano at infineon.com>
> 
> nor->addr_mode_nbytes is set during SFDP parse. Infineon SEMPER flash
> family relies on that parameter to read and write registers. To support
> use cases of skipping SFDP, set address mode in device specific setup()
> function.
> 
> Tested-by: Hiroyuki Saito <Hiroyuki.Saito2 at infineon.com>
> Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano at infineon.com>
> ---
>  drivers/mtd/spi/spi-nor-core.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c
> index 6f352c5c0e2..e382a518a34 100644
> --- a/drivers/mtd/spi/spi-nor-core.c
> +++ b/drivers/mtd/spi/spi-nor-core.c
> @@ -3794,6 +3794,16 @@ static int s25_s28_setup(struct spi_nor *nor, const struct flash_info *info,
>  #ifdef CONFIG_SPI_FLASH_BAR
>  	return -ENOTSUPP; /* Bank Address Register is not supported */
>  #endif
> +
> +	/* Setup address mode here, in case SFDP is skipped. */

Under which conditions is the SFDP skipped?

> +	if (!nor->addr_mode_nbytes) {
> +		ret = set_4byte(nor, nor->info, 1);

why do you need this call? Isn't enough the one done in spi_nor_init()?

Cheers,
ta> +		if (ret)
> +			return ret;
> +
> +		nor->addr_mode_nbytes = 4;
> +	}
> +
>  	/*
>  	 * S25FS256T has multiple sector architecture options, with selection of
>  	 * count and location of 128KB and 64KB sectors. This driver supports