linux-kernel - Re: [PATCH 1/3] dt-bindings: spi: Add VIA/WonderMedia serial flash controller

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <CABjd4YyMavJ414JY4bfouTDy41wB=aajJvJ6vCM55mdEiTFPDw@mail.gmail.com>
Date: Mon, 9 Jun 2025 13:15:22 +0400
From: Alexey Charkov <alchark@...il.com>
To: Miquel Raynal <miquel.raynal@...tlin.com>
Cc: Krzysztof Kozlowski <krzk@...nel.org>, Rob Herring <robh@...nel.org>, Mark Brown <broonie@...nel.org>, 
	Krzysztof Kozlowski <krzk+dt@...nel.org>, Conor Dooley <conor+dt@...nel.org>, 
	Tudor Ambarus <tudor.ambarus@...aro.org>, Pratyush Yadav <pratyush@...nel.org>, 
	Michael Walle <mwalle@...nel.org>, Richard Weinberger <richard@....at>, 
	Vignesh Raghavendra <vigneshr@...com>, linux-spi@...r.kernel.org, devicetree@...r.kernel.org, 
	linux-kernel@...r.kernel.org, linux-mtd@...ts.infradead.org, 
	linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH 1/3] dt-bindings: spi: Add VIA/WonderMedia serial flash controller

On Mon, Jun 9, 2025 at 1:07 PM Miquel Raynal <miquel.raynal@...tlin.com> wrote:
>
> Hi Alexey,
>
> >> > Happy to reference the spi-controller.yaml binding if so.
> >>
> >> SPI NOR flashes are still child devices of an SPI controller. You can
> >> look at other examples - aren't they all using spi-controller? Why this
> >> would be different? Unless you found some cases that are different, but
> >> then which ones?
> >
> > No strong opinions here, and no expectation of any special treatment
> > :) Just wanted to consult on what's most appropriate.
> >
> > My (subjective and perhaps unfounded) expectation when seeing
> > something advertise itself as an SPI controller was that it would be a
> > general purpose SPI master, to which one can e.g. connect an SPI
> > driven LCD screen and get it to work with generic Linux SPI
> > infrastructure - which would not be possible with this single-purpose
> > NOR-only flash controller. Given that I don't know how flexible or
> > restrictive other examples are in terms of driving arbitrary SPI
> > devices, I thought it's better to just ask.
> >
> > What I'm getting from this exchange here is that I'd better use the
> > spi-controller binding and respective node names regardless of the
> > fact that this controller cannot drive arbitrary SPI devices beyond
> > NOR flash (which, as I'm getting, is irrelevant after all).
>
> Just for information, there are several SPI controllers which are
> optimized for flash handling (not only NOR, though) and for that we have
> a spi-mem layer which allows to reference a set of SPI memory "only"
> callbacks. On the description side though, these controllers are like
> all other SPI controllers, so the same controller bindings may apply.

Noted, thank you Miquèl!

Best regards,
Alexey