Re: [PATCH v6 3/6] drm: Add driver for Solomon SSD130x OLED displays
From: andriy.shevchenko@xxxxxxxxxxxxxxx
Date: Wed Jun 01 2022 - 12:58:34 EST
On Wed, May 25, 2022 at 09:46:24PM +0200, Javier Martinez Canillas wrote:
> On 3/10/22 14:11, Dominik Kierner wrote:
...
> > # DRM Mode Configuration via Device Tree
> >
> > In the old fbdev driver, the display modes are hard-coded, which means
> > for every new display configuration, a new patch needs to be mainlined,
> > which slows down official Kernel support and
> > puts burden on the maintainers.
> > Additionally, with the DRM-subsystem supporting height and length
> > information, for scaling, this opens up a lot of new combinations.
> > The SSD1306 for example, is available in multiple resolutions like
> > 128x64 and 96x16 and comes in different sizes per resolution as well.
> > Just to name a few:
> > * 128x64 0.96" (22x11mm)
> > * 128x64 1.3" (30x15mm)
> > * 96x16 0.69" (18x3mm)
> >> Instead of hard-coding, I would suggest something along the lines of
> > of_get_drm_display_mode().
> > The displays won't need to support multiple modes at the same time,
> > let alone support for switching between them,
> > so the one-time invocation of this expensive function might be worth it.
> > maybe a new and simpler function that could be named:
> > of_get_drm_display_mode_simple()
>
> This makes sense to me as well.
What about non-OF platforms? Please, do not spread OF-only interfaces,
and use fwnode instead.
> > Providing a mode could later prove useful for a conversion to
> > drm_panel, if that is feasible.
> >
> > But for a function like this, I have to chicken out.
--
With Best Regards,
Andy Shevchenko