tree dbf1427de306ae36e5e63ee8e9a095cef09fd206
parent 8d653fff1b48a52ec3759e8e9be749c07d24eb5e
author Takahiro Kuwano <Takahiro.Kuwano@infineon.com> 1728965312 +0900
committer Tom Rini <trini@konsulko.com> 1729004269 -0600

mtd: spi-nor: Allow flashes to specify MTD writesize

Some flashes like the Infineon SEMPER NOR flash family use ECC. Under
this ECC scheme, multi-pass writes to an ECC block is not allowed.
In other words, once data is programmed to an ECC block, it can't be
programmed again without erasing it first.

Upper layers like file systems need to be given this information so they
do not cause error conditions on the flash by attempting multi-pass
programming. This can be done by setting 'writesize' in 'struct
mtd_info'.

Set the default to 1 but allow flashes to modify it in fixup hooks. If
more flashes show up with this constraint in the future it might be
worth it to add it to 'struct flash_info', but for now increasing its
size is not worth it.

This patch replicates the following upstream linux commit:
afd473e85827 ("mtd: spi-nor: core: Allow flashes to specify MTD writesize")

Acked-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>