[PATCH] pinctrl: imx5: start numbering pad from 0

[Shawn Guo]

On Wed, Aug 15, 2012 at 11:49:01AM -0500, Matt Sealey wrote:
> > Rather than betting how DTC will implement macro, we'd better make the
> > the safest assumption - it will not support that syntax.
> 
> It won't.

There were a lot of pushing on macro support for DTC.  Though it's
going to be very slow, I guess someday we will have it at least for
those simple and straight-forward syntax.

But right, we shouldn't make any assumption on that.

> DT is defined by properties and those properties have cells.
> Properties
> that have more than one cell or multiple definitions in them have to have a
> #size-cells property to go with it somehow.
> 
> I don't see what the problem would be here; you want to define pin properties,
> sure, they are intrinsically defined by 3 possible registers and value pairs. In
> actual fact if you drill down to this, what happens is you get a pin property
> which defines offsets into the unit, and values to stuff into those
> registers, so
> you could either dictate a size-cell of 6 (3 pairs of reg-value) or 2
> (reg, value).
> It would be more convenient for a driver to know what those pairs are maybe,
> so 6 is better.

<snip>

> iomuxc at 0x73f08000 {
>   fsl,iomux-pins = <mux value ctrl value ipp value
> /* MX53_PIN_SD4_CMD__SD4_CMD */
>                             mux value ctrl value ipp value
>        /* etc. */
>                             ...>;
> 
I do not see problem with this approach either.  But, this is nothing
IMX specific.  Essentially, this becomes a common binding for
configuring a pin with arbitrary number of register/value pairs.

-- 
Regards,
Shawn