Re: [PATCH] mtd: spinand: fmsh: fix FM25G01B/FM25G02B Quad I/O read dummy cycles

[Miquel Raynal]

Hi Aleksandr,

On 15/07/2026 at 23:36:02 +03, Aleksandr Mineev <sanderrrs@xxxxxxxxx> wrote:

> The FM25G01B/FM25G02B datasheets specify a single dummy byte for the
> 0xEB Quad I/O read-from-cache operation, but the generic
> read_cache_variants set uses two dummy bytes for the 1S-4S-4S variant.
> The extra dummy byte shifts the data phase and returns corrupted data
> with no ECC error, breaking boot on boards using these chips.
>
> Use a dedicated read-from-cache variant set with ndummy=1 for the
> 1S-4S-4S (0xEB) operation.
>
> FM25G01B datasheet: https://www.fmsh.com/nvm/FM25G01B_ds_eng.pdf
> FM25G02B datasheet: https://www.fmsh.com/nvm/FM25G02B_ds_eng.pdf
>
> Fixes: d5a5c9eb2ee9 ("mtd: spinand: fmsh: add support for FM25G{01,02}B")

Missing Cc: stable tag.

> Signed-off-by: Aleksandr Mineev <sanderrrs@xxxxxxxxx>

Otherwise LGTM.

Thanks,
Miquèl