Re: [PATCH 00/12] of: overlay: clean up device tree overlay code

From: Tomi Valkeinen
Date: Thu Oct 05 2017 - 02:53:52 EST


ï
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

On 04/10/17 17:56, Rob Herring wrote:
> On Mon, Oct 2, 2017 at 10:53 PM, <frowand.list@xxxxxxxxx> wrote:
>> From: Frank Rowand <frank.rowand@xxxxxxxx>
>>
>> I have found the device tree overlay code to be difficult to read and
>> maintain. This patch series attempts to improve that situation.
>>
>> The cleanup includes some changes visible to users of overlays. The
>> only in kernel user of overlays is fixed up for those changes. The
>> in kernel user is:
>>
>> drivers/gpu/drm/tilcdc/tilcdc_slave_compat.c
>
> At what point can we remove this? I'm assuming at some point users
> will need to update their dtb's for other reasons and this becomes
> obsolete.

To be honest, I have no idea, or how to find that out.

Do we need to get rid of it? Afaik, we haven't do much (or any?)
maintenance on tilcdc_slave_compat.c since it was written, so from our
perspective it's been a minimal burden. Is it creating burden for others?

Is the approach done with tilcdc_slave_compat.c something that's not
recommended? I'm sure similar situations happen with other drivers too,
and I think it's a good idea to have a recommended way of keeping
compatibility.

Tomi