Re: [PATCH 6/6] documentation: bindings: document PMIC8921/8058 RTC

[Josh Cartwright <joshc@codeaurora.org>]

Hey Rob-

Thanks for the reply.

On Mon, Mar 10, 2014 at 10:35:25AM -0500, Rob Herring wrote:
> On Wed, Mar 5, 2014 at 6:00 PM, Josh Cartwright <joshc@codeaurora.org> wrote:
> > On Wed, Mar 05, 2014 at 12:58:55PM -0800, Stephen Boyd wrote:
> >> On 03/05/14 11:29, Josh Cartwright wrote:
> >> > +- interrupts: interrupt list for the RTC, must contain a single interrupt
> >> > +              specifier for the alarm interrupt
> >> > +- interrupt-names: corresponding interrupt names for the interrupts listed in
> >> > +                   the 'interrupts' property, must contain:
> >> > +     "alarm" - summary interrupt for PMIC peripherals
> >>
> >> optional interrupt-names?
> >
> > It isn't clear to me why these should be made optional, I hope Rob
> > provides some clarification in the sdhci-msm thread.
>
> Because reg and interrupt names are relatively new and reluctantly
> added by DT maintainers. Personally, I think it was a mistake and it
> is simply Linux specific information leaking into the DT, but it did
> make transition to DT easier.

I don't necessarily buy the Linux-specific argument in general.  If a
devices' datasheet clearly gives names to register regions and
interrupts, what about reflecting these names in the bindings is
Linux-specific?

Now, there are probably abuses of this, where the reg-names and
interrupt-names are abused to ensure driver compatibility with devices
described in board files, and only in that case will I agree is
Linux-specific and should be strongly discouraged.

> The requirement is still the ordering of reg and interrupts fields
> must be defined and you cannot rely on the names to define the order.

Should this requirement also exist for other <foo>-names properties?

> It is quite pointless here since you only have 1 field.

Indeed in the interrupt case it is worthless, as there is only one alarm
interrupt.  However for registers I do plan to extend this binding in
the future to document a newer RTC which does split registers across
multiple named address regions.

Thanks again,
  Josh

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