Subject: [PATCH 1/8] ARM: dts: bcm283x: Define standard pinctrl groups in the gpio node.

From: [email-masked] (Gerd Hoffmann)
Date: Thu, 08 Sep 2016 09:48:48 +0200

On Mi, 2016-09-07 at 11:50 -0700, Eric Anholt wrote:
> Stefan Wahren <[email-masked]> writes:
> 
> > Hi Gerd,
> >
> >> Gerd Hoffmann <[email-masked]> hat am 7. September 2016 um 12:31
> >> geschrieben:
> >> 
> >> 
> >> From: Eric Anholt <[email-masked]>
> >> 
> >> The BCM2835-ARM-Peripherals.pdf documentation specifies what the
> >> function selects do for the pins, and there are a bunch of obvious
> >> groupings to be made.  With these created, we'll be able to replace
> >> bcm2835-rpi.dtsi's main "set all of these pins to alt0" with
> >> references to specific groups we want enabled.
> >
> > on IMX/MXS platform it's unwanted to add all possible muxes in the dtsi file. So
> > i would suggest to add only the actually used muxes. That makes it easier to
> > maintain.
> 
> On the other hand, I find that having to go back to the docs for
> determining the fsels is worse than just verifying and defining them
> here all at once.

Agreeing here.  IMO it is nice to have them all even if unused for
documentation purposes.

> Maintaining has also gotten harder because our DTs
> are split across 32 and 64-bit ARM, so rpi3 changes that require adding
> one of these pinmux definitions back to the dtsi would require painful
> cross-branch merges.

It'll also easily cause merge conflicts.

cheers,
  Gerd