Re: Re: Re-using sun5i-a13.dtsi for the r8 ?

[Maxime Ripard <maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>]

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On Tue, Aug 25, 2015 at 10:24:51AM +1000, Julian Calaby wrote:
> Hi Maxime,
> 
> On Tue, Aug 25, 2015 at 12:26 AM, Maxime Ripard
> <maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> wrote:
> > Hi,
> >
> > On Fri, Aug 21, 2015 at 09:53:07AM +0200, Hans de Goede wrote:
> >> I just realized that I never answered your question about the need
> >> for a tvencoder simplefb node in sun5i-a13.dtsi, like the one from
> >> the "ARM: dts: sun5i: Add simplefb node for tvencoder output"
> >>
> >> I think the real question is do we want to use sun5i-a13.dtsi for
> >> the r8 ?
> >
> > So far, the only information I got about the R8 was that it was
> > strictly identical to the A13, and it was making sense to re-use it
> > entirely.
> 
> Does having the tvout pin change the pinmux options or is that pin
> strictly single use?
>
> (And if it is strictly single use, is adding that pin the entirety of
> the software visible hardware changes?)

I have no idea.

> >> I would expect us to use a sun5i-r8.dtsi, this one could then
> >> include sun5i-a13.dtsi, and have the extra simplefb node for
> >> the tvencoder. Putting the simplefb node for the tvencoder
> >> in sun5i-a13.dtsi feels wrong because the A13 package does
> >> not have a tvout pin.
> >
> > But if it turns out it's not, then yeah, we'll have to make another
> > DTSI.
> 
> IMHO that's enough of a change to warrant a new DTSI,

Yep.

> I feel that someone's going to use the lack of DTSI as "proof" that
> we don't support the R8 or try to use the tv encoder on an A13.

But that argument is dubious. That's not how it works. The list of
DTSIs has never been comprehensive list of the supported SoCs.

We support SoCs that don't have a DTSI (like we can see with the R8),
and we also support, and even support DT that don't even have a
matching machine. It's never been that way, and will never be.

Plus, you're never actually using the DTSI directly, just the board
DT, that will be there.

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com