Hi!

> > You may want to learn more about device tree and/or talk to the device
> > tree maintainers. This is an old article. https://lwn.net/Articles/561462/
> 
> The article title is "Device trees as ABI". A device tree is defined
> in the "*.dts" file that is then compiled to a dtb blob, which
> constitutes the ABI. And this ABI should be kept backwards compatible.
> 
> What is discussed here is a documentation of bindings, i.e. according
> to ePAPR: "requirements for how specific types and classes of devices
> are represented in the device tree".
> 
> >From the bindings documented in the
> Documentation/devicetree/bindings/mfd/ti-lmu.txt only
> ti,lm3532-backlight is used in the mainline dts file
> (arch/arm/boot/dts/omap4-droid4-xt894.dts).
> 
> Having the above it seems that there is no risk of breaking any
> users.

DTBs and bindings are supposed to be portable between operating
systems. You are right there are no _mainline_ _Linux_ users.

> > NAK on this patch. I see that this binding has problems, but
> > introducing different binding for subset of devices is _not_ a fix.
> > 
> >>> What about the multi function devices? They should have same binding.
> >>
> >> The MFD devices defined are not in contention here only the SFD.
> > 
> > I'd like to see common solutions for SFD and MFD, as the hardware is
> > similar, and that includes the code. Having code that is easier to
> > maintain is important, and having many drivers are harder to maintain
> > than one driver.
> > 
> > Milo's code looks better than yours in that regard. I disagree about
> > Milo's code being "nightmare" to modify, and care about "easy to
> > maintain" more than "binary size".
> 
> Easy to maintain will be a dedicated LED class driver.

You mean, 3 dedicated LED class drivers and 3 MFD drivers with LED
parts? We'll need complex driver anyway, and I'd really like to have
just one.

								Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html