RE: [RFC 4/5] arm: dts: r7s1000: Add pincontroller node

[Chris Brandt <Chris.Brandt@xxxxxxxxxxx>]

Hi Laurent (and Jacopo)

On Tuesday, January 31, 2017, Laurent Pinchart wrote:
> On Monday 30 Jan 2017 19:39:33 Chris Brandt wrote:
> > On Monday, January 30, 2017, Laurent Pinchart wrote:
> > >> +	pinctrl: pinctrl@fcfe3000 {
> > >> +		compatible = "renesas,rza1-pinctrl";
> > >> +		#address-cells = <1>;
> > >> +		#size-cells = <0>;
> > >> +
> > >> +		#pinctrl-cells = <2>;
> > >> +
> > >> +		reg = <0xfcfe3000 0xa30>, /* Pn, ..., PFCAEn */
> > >> +		      <0xfcfe7000 0x230>, /* PIBCn, ..., PIPCn */
> > >
> > > What's the reason for splitting those registers in two sets ? Maybe
> > > you can explain that in the DT bindings documentation that this
> > > patch series is missing ;-)
> >
> > I left this out of my review comments, but even though the chip
> > designers left a BIG HOLE in the memory map of the PFC controller, I
> > don't think it will 'cost' you anything by just mapping the whole area
> > (dead space and
> > all) and getting rid of the "high and low" memory indexing thing that
> > you are doing in the driver.
> > There is nothing mapped in that dead area anyway.
> 
> For the first two areas, I agree. The third area is a separate pin
> controller for the JTAG port, not multiplexed with the GPIO ports. I even
> wonder whether it should be split in a separate DT node.


I think we should just forget about the JTAG pins completely.
Honestly, they are 2 pins that can only be configured as JTAG or a GPIO input
(not even output).
No one is using those pins for anything other than JTAG.

IMHO, adding extra support just for those 2 pins is basically a waste of code.


Chris
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