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

[Asmaa Mnebhi]

Thanks for your reply Wolfram. All customers using BlueField hardware need to install our internal Firmware (proprietary) before booting any customized OS so they will always use ACPI tables. So I think it is safe to remove it. Any feedback from the DT list would be greatly appreciated! 

-----Original Message-----
From: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx> 
Sent: Wednesday, September 21, 2022 4:02 PM
To: Asmaa Mnebhi <asmaa@xxxxxxxxxx>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; robh@xxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-i2c@xxxxxxxxxxxxxxx; Khalil Blaiech <kblaiech@xxxxxxxxxx>
Subject: How to remove DT support from a driver? (was Re: [PATCH v5 8/8] i2c: i2c-mlxbf.c: Update binding devicetree)

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.

Maybe the DT list has more to add here?

Happy hacking,

   Wolfram

[1] http://patchwork.ozlabs.org/project/linux-i2c/list/?series=73827&state=*