Re: [PATCH v1] spi: fix client driver breakages when using GPIO descriptors

From: Linus Walleij
Date: Tue Nov 17 2020 - 20:03:57 EST


On Mon, Nov 16, 2020 at 10:06 PM Mark Brown <broonie@xxxxxxxxxx> 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