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

[Frieder Schrempf]

On 31.05.23 14:58, Dario Binacchi wrote:
> Hi Frieder, All
> 
> On Wed, May 31, 2023 at 12:58 PM Frieder Schrempf
> <frieder.schrempf at kontron.de> wrote:
>>
>> On 17.05.23 09:43, Frieder Schrempf wrote:
>>> Hi Michael, hi Dario,
>>>
>>> On 15.05.23 23:33, Michael Nazzareno Trimarchi wrote:
>>>> Hi
>>>>
>>>> Il lun 15 mag 2023, 23:12 Tom Rini <trini at konsulko.com
>>>> <mailto: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
>>>>     <mailto: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
>>>>     <mailto: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
>>>>     <mailto:gch981213 at gmail.com>> patch
>>>>     > >>>>>> submitted to linux kernel
>>>>     > >>>>>>
>>>>     > >>>>>> Signed-off-by: Mikhail Kshevetskiy
>>>>     <mikhail.kshevetskiy at iopsys.eu <mailto:mikhail.kshevetskiy at iopsys.eu>>
>>>>     > >>>>>> Signed-off-by: Frieder Schrempf
>>>>     <frieder.schrempf at kontron.de <mailto: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
>>>>     <http://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.
>>>
>>> I can see patch 1/5 of this series in the nand-next tree. What about the
>>> other four patches of this series? Please pick them up, too!
>>
>> Ping, again! I will just keep on doing this and hope at some point you
>> will pick up the patches.
> 
> Applied to nand-next.

Thanks a lot, Dario!