Re: [PATCH 3/4] drm/tiny: Add driver for Solomon SSD1307 OLED displays

Javier Martinez Canillas
2022-02-01T15:10:58Z

On 2/1/22 15:02, Andy Shevchenko wrote:
> On Tue, Feb 01, 2022 at 12:45:53PM +0100, Javier Martinez Canillas wrote:
>> On 2/1/22 10:44, Andy Shevchenko wrote:
>>> On Tue, Feb 01, 2022 at 01:14:22AM +0100, Javier Martinez Canillas wrote:
>
> ...
>
>>> The problem with no backward compatibility means that removal of old driver
>>> makes users unhappy since DT is kinda ABI and we do not break it.
>>>
>>
>> I think that's the crux of the issue. Do we want people to update their
>> kernel but using their existing Device Tree and be able to switch to the
>> DRM driver ?
>>
>> My take is that we should and that's why I kept the backward compatibility.
>>
>> Maybe we could do that in the meantime and at some point introduce new DT
>> bindings (with a different compatible string) that would use the latest
>> and greatest conventions in DT ? That seems to be a good compromise.
>
> I have over-read in this discussion that current binding is not fully
> correct from hw perspective. If it's indeed the case (and I believe it's),
> then probably we should come with brand new driver with ssd130x name and
> incompatible bindingas (*).
>
> Otherwise in this driver we continue to be incorrect in them.
>

See the comment from Geert. I believe we should use the existing binding.

> *) But even though I think it would be good if you take the old one under your
> maintainership.
>

Sure, now that I got familiar with the ssd130x devices, I'll be happy to
help with the ssd1307fb driver maintainership.

Best regards,
--
Javier Martinez Canillas
Linux Engineering
Red Hat