[PATCH v4 2/2] mtd: spinand: macronix: Use the flag in Macronix driver

[Cheng Ming Lin]

Hi Miquel,

Miquel Raynal <miquel.raynal at bootlin.com> 於 2024年8月30日 週五 下午3:23寫道：
>
> Hi ChengMing,
>
> linchengming884 at gmail.com wrote on Thu, 29 Aug 2024 11:25:17 +0800:
>
> > From: Cheng Ming Lin <chengminglin at mxic.com.tw>
> >
> > Macronix serial NAND flash with a two-plane structure requires
> > insertion of the Plane Select bit into the column address during
> > the write_to_cache operation.
> >
> > Additionally, for MX35{U,F}2G14AC and MX35LF2GE4AB, insertion of
> > the Plane Select bit into the column address is required during
> > the read_from_cache operation.
> >
>
> PATH 1 is fine except the commit title, let me explain. Once applied in
> the kernel tree, there is no cover letter anymore. So both titles would
> be "Add support for the flag" and "Use the flag...", which is really
> missing the important information as we don't know what this flag is
> for. Furthermore, the fact that we decided to use a flag is an
> implementation detail, what is important is the feature: setting the
> plane select bit.
>
> Can you please change the first commit title to:
>
> mtd: spinand: Add support for setting plane select bits
>
> and for the second, something like:
>
> mtd: spinand: macronix: Flag parts needing explicit plane select
>

Sure, I will update the commit titles as suggested.

> > Signed-off-by: Cheng Ming Lin <chengminglin at mxic.com.tw>
> > ---
> >  drivers/mtd/nand/spi/macronix.c | 17 ++++++++++-------
> >  1 file changed, 10 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/mtd/nand/spi/macronix.c b/drivers/mtd/nand/spi/macronix.c
> > index 3f9e9c572854..f17cd4a6f4d0 100644
> > --- a/drivers/mtd/nand/spi/macronix.c
> > +++ b/drivers/mtd/nand/spi/macronix.c
> > @@ -118,7 +118,8 @@ static const struct spinand_info macronix_spinand_table[] = {
> >                    SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
> >                                             &write_cache_variants,
> >                                             &update_cache_variants),
> > -                  SPINAND_HAS_QE_BIT,
> > +                  SPINAND_HAS_QE_BIT | SPINAND_HAS_PP_PLANE_SELECT_BIT |
> > +                  SPINAND_HAS_READ_PLANE_SELECT_BIT,
>
> And I know this is not what the normal coding style would ask for, but
> I would prefer to have the two plane select bits on the same line if
> possible, otherwise on two independent lines, so either:
>
>                 QE_BIT |
>                 PP_SELECT_BIT | READ SELECT_BIT,
>
> or otherwise:
>
>                 QE_BIT |
>                 PP_SELECT_BIT |
>                 READ SELECT_BIT,
>
> And finally, could we name the former
>
>                 SPINAND_HAS_PROG_PLANE_SELECT_BIT
>
> ? Because "PP" sounds a little bit too cryptic.
>

No problem. I will adjust the formatting to have the two plane select bits on
separate lines and also rename it to SPINAND_HAS_PROG_PLANE_SELECT_BIT
to avoid any confusion.

> Thanks,
> Miquèl

Thanks,
Cheng Ming Lin