Re: How to remove DT support from a driver? (was Re: [PATCH v5 8/8] i2c: i2c-mlxbf.c: Update binding devicetree)

From: Rob Herring
Date: Sat Sep 24 2022 - 13:31:33 EST


On Wed, Sep 21, 2022 at 10:01:59PM +0200, Wolfram Sang wrote:
> Hi,
>
> > I have a question for you and Wolfram, we don’t use device trees and
> > are not planning to use device trees; we only use ACPI tables. But I
> > think when Khalil submitted the first version of the i2c-mlxbf.c
> > driver, it was requested from him to add devicetree support. Do you
> > know why? Is it possible to remove the device tree support and so this
> > doc? or is devicetree support a requirement regardless of the actual
> > implementation?
>
> The first version sent from Khalil to the public I2C mailing list already
> had DT bindings [1]. I don't see a sign of someone of the public list
> requesting DT bindings. Maybe it was company internal?
>
> Technically, there is no requirement to support DT, especially since you
> have working ACPI. I don't know the process, though, of removing DT
> support. You would basically need to be sure that no user made use of
> the DT bindings introduced before. I don't know to what degree you can
> assume that.

There's the whole using DT bindings in ACPI bindings thing, but I have
little interest (or time) in supporting that. Maybe that's what's
happening here? I haven't looked. The whole concept is flawed IMO. It
may work for simple cases of key/value device properties, but the ACPI
model is quite different in how resources are described and managed.

Rob