Re: [PATCH v3 1/3] dt-bindings: can: nxp,sja1000: Document RZ/N1 power-domains support

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Krzysztof,

On Tue, Aug 30, 2022 at 9:03 PM Krzysztof Kozlowski
<krzysztof.kozlowski@linaro.org> wrote:
> On 30/08/2022 20:47, Biju Das wrote:
> >> Subject: Re: [PATCH v3 1/3] dt-bindings: can: nxp,sja1000: Document
> >> RZ/N1 power-domains support
> >>
> >> On 30/08/2022 19:45, Biju Das wrote:
> >>> Document RZ/N1 power-domains support. Also update the example with
> >>> power-domains property.
> >>>
> >>> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
> >>> ---
> >>> v3:
> >>>  * Documented power-domains support.
> >>
> >> You made them required, so it would be nice to see reason in such
> >> change. The commit msg says only what you did, but not why you did it.
> >
> > It is simple. As you see from [1] and [2] power-domains are enabled by default in RZ/N1 SoC.
> > So there is nothing prevent us to document this property for all IP's present in
> > RZ/N1 SoC.
>
> Any explanation I expect to see in commit msg.
>
> Anyway you referred to Linux drivers, which is not actually a reason.
> What if some device is not in a power domain?

DT describes hardware, not software policy.

"power domains" are a property of the hardware.
I.e. this device (like most other devices on the SoC) is power-managed
through the system-controller.

Whether software does that by explicitly managing the clocks, or by
having a PM Domains driver is a software detail.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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