Re: [PATCH v1 05/35] drm/connector: Add TV standard property

From: Geert Uytterhoeven
Date: Wed Aug 17 2022 - 03:31:37 EST


Hi Maxime,

On Tue, Aug 16, 2022 at 5:50 PM Maxime Ripard <maxime@xxxxxxxxxx> wrote:
> On Tue, Aug 16, 2022 at 04:43:44PM +0200, Geert Uytterhoeven wrote:
> > > > > > Either you have to add them here (e.g. "hd720p50" and "hd720p60"), or
> > > > > > handle them through "@<refresh>". The latter would impact "[PATCH v1
> > > > > > 09/35] drm/modes: Move named modes parsing to a separate function", as
> > > > > > currently a named mode and a refresh rate can't be specified both.
> > > > >
> > > > > I think the former would make more sense. It simplifies a bit the
> > > > > parser, and we're going to use a named mode anyway.
> > > > >
> > > > > > As "[PATCH v1 34/35] drm/modes: Introduce the tv_mode property as a
> > > > > > command-line option" uses a separate "tv_mode" option, and not the main
> > > > > > mode name, I think you want to add them here.
> > > > >
> > > > > It's a separate story I think, we could have a named mode hd720p50,
> > > > > which would be equivalent to 1280x720,tv_mode=hd720p
> > > >
> > > > So where's the field rate in "1280x720,tv_mode=hd720p"?
> > >
> > > Yeah, sorry I meant 1280x720@50,tv_mode=hd720p
> >
> > Above you said "I think the former would make more sense", so that
> > should be "1280x720,tv_mode=hd720p50"?
>
> No, 720p at 50Hz would be either hd720p50 or 1280x720@50,tv_mode=hd720p
> and 60Hz would be hd720p60 or 1280x720@60,tv_mode=hd720p

I disagree: hd720p50 and hd720p60 are different TV modes.
Treating them the same would be similar to treating unmodulated (e.g.
component) PAL-N (25 frames/s) and PAL-M (30 frames/s) the same.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds