linux-kernel - Re: [PATCH v1 17/43] dt-bindings: spi: Add Cirrus EP93xx

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

Message-ID: <b2fc1733-4841-42e9-8bf7-1534a5d1a1b4@sirena.org.uk>
Date:   Thu, 1 Jun 2023 13:55:03 +0100
From:   Mark Brown <broonie@...nel.org>
To:     Nikita Shubin <nikita.shubin@...uefel.me>
Cc:     Alexander Sverdlin <alexander.sverdlin@...il.com>,
        Arnd Bergmann <arnd@...db.de>,
        Linus Walleij <linus.walleij@...aro.org>,
        Rob Herring <robh+dt@...nel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
        Michael Peters <mpeters@...eddedts.com>,
        Kris Bahnsen <kris@...eddedts.com>, linux-spi@...r.kernel.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v1 17/43] dt-bindings: spi: Add Cirrus EP93xx

On Thu, Jun 01, 2023 at 03:41:54PM +0300, Nikita Shubin wrote:
> Mark Brown <broonie@...nel.org> wrote:
> > On Thu, Jun 01, 2023 at 08:34:08AM +0300, Nikita Shubin wrote:

> > > +  cirrus,ep9301-use-dma:
> > > +    description: Flag indicating that the SPI should use dma
> > > +    type: boolean  

> > My previous feedback on this property still applies.

> > > +  cirrus,ep9301-use-dma:

> The reason is that ep93xx DMA state is not quite device-tree ready at
> this moment, and clients use it with the help of:

> https://elixir.bootlin.com/linux/v6.4-rc4/source/include/linux/platform_data/dma-ep93xx.h

> I was hoping to slip by without changing much in ep93xx DMA driver, so

You're definign new ABI here, that's not a good thing to do for a
temporary workaround.

> I can move "use-dma" to module parameters, if this is acceptable.

That's less bad.  I guess you could also define the bindings for the DMA
controller so that the properties are there then instead of properly
using the DMA API in the clients just check to see if the DMA properties
are present and then proceed accordingly?

Download attachment "signature.asc" of type "application/pgp-signature" (489 bytes)