Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20201106150706.29089-1-TheSven73@gmail.com> <CAHp75VfP1R7bXV6nWWnovWB5BMFcNNEmwBQXheBCUVDbr=xXGA@mail.gmail.com>
 <CAGngYiVu3cXtzb5PaoDOoyqjuuohLQ+em6Keg-qgDFFn2tdp=Q@mail.gmail.com>
 <CACRpkdagAK1X6FT=sug5FGA1iipXnOT_ujtMBh9cVnep_DpWyA@mail.gmail.com>
 <20201111123327.GB4847@sirena.org.uk> <CACRpkdZW3G48Yj3yGMTKZGwVEQOSs1VeVTTGLgyoJViM3=Yedg@mail.gmail.com>
 <20201116210632.GJ4739@sirena.org.uk>
In-Reply-To: <20201116210632.GJ4739@sirena.org.uk>
From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Wed, 18 Nov 2020 02:03:41 +0100
Message-ID: <CACRpkdayWzWKHv69cg_GL2O=NWozqi_ZLnH1WdMOHzEb1bU-xA@mail.gmail.com>
Subject: Re: [PATCH v1] spi: fix client driver breakages when using GPIO descriptors
To:     Mark Brown <broonie@kernel.org>
Cc:     Grant Likely <grant.likely@arm.com>,
        Rob Herring <robh+dt@kernel.org>,
        Sven Van Asbroeck <thesven73@gmail.com>,
        Andy Shevchenko <andy.shevchenko@gmail.com>,
        Jonathan Cameron <jonathan.cameron@huawei.com>,
        Simon Han <z.han@kunbus.com>, Lukas Wunner <lukas@wunner.de>,
        linux-spi <linux-spi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Mon, Nov 16, 2020 at 10:06 PM Mark Brown <broonie@kernel.org> wrote:
> On Wed, Nov 11, 2020 at 02:36:07PM +0100, Linus Walleij wrote:

> > I don't know if we ever formalized it, there is nowadays a rule akin to
>
> > "if a property can be determined from the compatible-string, and if the
> >  compatible-string is identifying the variant of the electronic component,
> >  then do not add this property to the device tree description. Just
> >  deduce it from the compatible-string, assign it with code to the device
> >  model of the operating system and handle it inside the operating system."
>
> > I think this, while clear and intuitive, wasn't at all clear and intuitive in
> > the recent past.
>
> I think the main push in the other direction has always been people who
> want to not have to write a driver at all and put absolutely everything
> into DT which has scaling issues :/

What I can't understand is what gave them that idea.

This thing looks like a dream to these people for example:
https://gist.github.com/Minecrell/56c2b20118ba00a9723f0785301bc5ec#file-dsi_panel_s6e88a0_ams452ef01_qhd_octa_video-dtsi
And it looks like a nightmare to me.

(There is even a tool to convert this description into a proper display
driver now.)

It just seems to be one of those golden hammer things: everything
start to look like nails.

Yours,
Linus Walleij