Re: [PATCH 03/30] mtd: spi-nor: winbond: Stop filling the .name entry

From: "Michael Walle" <mwalle@kernel.org>
To: "Miquel Raynal" <miquel.raynal@bootlin.com>
Cc: "Pratyush Yadav" <pratyush@kernel.org>,
	"Takahiro Kuwano" <takahiro.kuwano@infineon.com>,
	"Richard Weinberger" <richard@nod.at>,
	"Vignesh Raghavendra" <vigneshr@ti.com>,
	"Thomas Petazzoni" <thomas.petazzoni@bootlin.com>,
	"Steam Lin" <STLin2@winbond.com>, <linux-mtd@lists.infradead.org>,
	<linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 03/30] mtd: spi-nor: winbond: Stop filling the .name entry
Date: Wed, 22 Jul 2026 15:23:32 +0200	[thread overview]
Message-ID: <DK54S6U9L51W.1BIED2GDI8AIK@kernel.org> (raw)
In-Reply-To: <8733xbji7s.fsf@bootlin.com>

On Wed Jul 22, 2026 at 2:56 PM CEST, Miquel Raynal wrote:
> On 06/07/2026 at 15:59:53 +02, "Michael Walle" <mwalle@kernel.org> wrote:
>
>> On Fri May 29, 2026 at 5:22 PM CEST, Miquel Raynal wrote:
>>> This is a legacy field, it is often incorrectly filled and will soon
>>> become very incorrect due to IDs being reused.
>>
>> And I thought winbond is doing better... So if you have a contact
>> there, please suggest they are putting a table with a unique
>> identifier per chip there. So we can use that to do fixups.
>
> Yes, this is something that has been raised, I can confirm. We found a
> way through the SFDP data to reliably identify which chip it is since
> the SFDP version has been reliably updated over time (see the RV and PW
> addition patches).

This seem to be two different things here. What I meant is that
Winbond will put a vendor table with a unique id per flash part in
it.

What you have now is some kind of way to differentiate between
existing flashes, that's good, but it's not a generic solution to
the problem.

The end goal here should be to make all flash vendor put a vendor
table into SFDP to sidestep the new notorious flash id reuse. IOW.
put a new id into the SFDP and do it correctly. We should push in
that direction.

>>> Replace the names with a comment above the entry with the newly instated
>>> naming scheme to indicate what chips are covered by each entry.
>>
>> This is exported via sysfs, so this could be a regression.
>>
>> Not sure..
>
> Yes, but the names are totally wrong. And become even wronger with the
> addition of the RV, PW, etc families. I was already asked to not put a
> name on the new additions, I believe we should drop those fields, they
> are very misleading. So what is your final position? Pratyush any
> feedback? I can keep the old names, but, well, you know my position,
> they are wrong and old.

Well, but that's actually on Winbond for just reusing the IDs :)
Sheldon me would also be dropping the wrong names, but yeah, it
might be an ABI now. Maybe a SFDP fixup could just unset the name
for newer flashes.

-michael

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