[PATCH 1/5] mtd/spinand: rework detect procedure for different READ_ID operation

[Michael Nazzareno Trimarchi]

Hi

Il lun 15 mag 2023, 23:12 Tom Rini <trini at konsulko.com> ha scritto:

> On Tue, May 09, 2023 at 09:09:28AM +0200, Frieder Schrempf wrote:
> > Hi Michael, hi Dario,
> >
> > On 18.04.23 15:46, Frieder Schrempf wrote:
> > > Hi Michael, Dario,
> > >
> > > On 28.03.23 09:57, Frieder Schrempf wrote:
> > >> Hi Michael,
> > >>
> > >> On 10.02.23 12:57, Michael Nazzareno Trimarchi wrote:
> > >>> Hi
> > >>>
> > >>> I will review
> > >>>
> > >>> On Thu, Feb 9, 2023 at 5:52 PM Tom Rini <trini at konsulko.com> wrote:
> > >>>>
> > >>>> On Thu, Feb 09, 2023 at 10:24:47AM +0100, Frieder Schrempf wrote:
> > >>>>> Hi,
> > >>>>>
> > >>>>> On 10.01.23 12:58, Frieder Schrempf wrote:
> > >>>>>> From: Mikhail Kshevetskiy <mikhail.kshevetskiy at iopsys.eu>
> > >>>>>>
> > >>>>>> Currently there are 3 different variants of read_id
> implementation:
> > >>>>>> 1. opcode only. Found in GD5FxGQ4xF.
> > >>>>>> 2. opcode + 1 addr byte. Found in GD5GxGQ4xA/E
> > >>>>>> 3. opcode + 1 dummy byte. Found in other currently supported
> chips.
> > >>>>>>
> > >>>>>> Original implementation was for variant 1 and let detect function
> > >>>>>> of chips with variant 2 and 3 to ignore the first byte. This isn't
> > >>>>>> robust:
> > >>>>>>
> > >>>>>> 1. For chips of variant 2, if SPI master doesn't keep MOSI low
> > >>>>>> during read, chip will get a random id offset, and the entire id
> > >>>>>> buffer will shift by that offset, causing detect failure.
> > >>>>>>
> > >>>>>> 2. For chips of variant 1, if it happens to get a devid that
> equals
> > >>>>>> to manufacture id of variant 2 or 3 chips, it'll get incorrectly
> > >>>>>> detected.
> > >>>>>>
> > >>>>>> This patch reworks detect procedure to address problems above. New
> > >>>>>> logic do detection for all variants separatedly, in 1-2-3 order.
> > >>>>>> Since all current detect methods do exactly the same id matching
> > >>>>>> procedure, unify them into core.c and remove detect method from
> > >>>>>> manufacture_ops.
> > >>>>>>
> > >>>>>> This is a rework of Chuanhong Guo <gch981213 at gmail.com> patch
> > >>>>>> submitted to linux kernel
> > >>>>>>
> > >>>>>> Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy at iopsys.eu
> >
> > >>>>>> Signed-off-by: Frieder Schrempf <frieder.schrempf at kontron.de>
> > >>>>>
> > >>>>> +Cc: Jagan, Tom
> > >>>>>
> > >>>>> Who is supposed to pick up these patches? Some of them have been
> around
> > >>>>> for some months (before I resent them).
> > >>>>>
> > >>>>> There is no maintainer for drivers/mtd/spinand/ and no maintainer
> for
> > >>>>> drivers/mtd/ in general.
> > >>>>>
> > >>>>> In Patchwork Jagan got assigned, but the get_maintainer.pl script
> didn't
> > >>>>> even add him to Cc, of course.
> > >>>>>
> > >>>>> Any ideas how to proceed?
> > >>>>
> > >>>> We don't have anyone dedicated to that area, yes, sadly. I've added
> > >>>> Michael and Dario as they've also been doing mtd-but-not-spi work of
> > >>>> late to see if they're interested. Or since you've long been working
> > >>>> here, would you like to more formally maintain the area? Thanks!
> > >>>
> > >>> They can come from our tree. I will try to sort out all my duties
> weeked
> > >>
> > >> Any news regarding reviewing/picking these patches?
> > >
> > > Ping!
> > >
> > > Can you please apply these patches, that have been waiting for so long?
> >
> > I still can't see this applied anywhere. You already told me to take
> > care of it multiple times. Can you please get it done?
>
> Yes, I'd really like to see a PR at least vs -next at this point so
> things aren't lost, thanks!
>

I think that we pick already it so it will happen.

Michael

>
> --
> Tom
>