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charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Last-TLS-Session-Version: TLSv1.3 Hello, On 10/09/2025 at 16:30:43 +02, "Jakub \"Kuba\" Czapiga" wrote: > Hi Miqu=C3=A8l, > > On Wed, Sep 10, 2025 at 2:05=E2=80=AFPM Miquel Raynal wrote: >> >> Hi Jakub, >> >> > diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c >> > index ac4b960101cc..79deee3a50d3 100644 >> > --- a/drivers/mtd/spi-nor/core.c >> > +++ b/drivers/mtd/spi-nor/core.c >> > @@ -2608,6 +2608,10 @@ static int spi_nor_setup(struct spi_nor *nor, >> > } >> > } >> > >> > + /* Some SPI controllers might not support CR read opcode. */ >> > + if (spi_nor_read_cr(nor, nor->bouncebuf) =3D=3D -EOPNOTSUPP) >> >> There is a spi_nor_spimem_check_op() helper which might be better suited >> for this purpose? > > spi_nor_spimem_check_op() works only for spi-mem devices. spi_nor_read_cr= () > handles both spi-mem and spi-nor controller. Using spi_nor_spimem_check_o= p() > would require adding a variation of spi_nor_read_cr() that would use > spi_nor_spimem_check_op() for spi-mem and spi_nor_controller_ops_read_reg= () > for spi-nor controller. > Another way would be to do this check only for the spi-mem as spi-nor > controllers seem to be deprecated in favour of spi-mem. I'll let that choice to SPI NOR maintainers but we've collectively asked to switch in favor of the spi memory API for quite some time, I would not care too much about compatibility with the two remaining controllers that have not yet been converted. But here is a proper illustration why spi-mem rocks and why SPI NOR controllers, besides making no sense (because we also have SPI NANDs now) have a flacky API as of today's standards. Thanks, Miqu=C3=A8l