[PATCH] ARM: ux500: Register pinctrl from platform code until it's been DT:ed

On Thu, Jul 5, 2012 at 11:36 AM, Lee Jones [off-list ref] wrote:

A way to link
the mapping tables registered with a platform device to the driver started
with Device Tree is missing. This can be over-come by several methods:

a) Create a binding which takes a device name to tag onto a mapping. This
can be used in the name based searches currently employed by pinctrl. This
is the binding I was talking about in the commit log. In retrospect, I can
see that this is not the correct solution.

This is what the generic bindings does. The binding already exists.
It's a matter of augmenting the device tree per se, and making sure
the static maps are not enabled if you have these nodes.

b) Continue using Device Tree and force the 'pinctrl-db8500' device name
which any string based searches will be expecting with AUXDATA(). We do
similar things for clock-names already. However, this must be seen as a
hacky work-around and it to be removed after full enablement has been taken
place.

c) Prevent the pinctrl driver from being started by Device Tree and allow
platform code to register the device until we can populate the device tree
with all of the mappings. This is the way you advised me to do it [see
below] and it's what this patch tries to achieve.

Yeah.

quoted

examples of how to do this in for example:
arch/arm/boot/dts/tegra-seaboard.dts

I don't see this file anywhere?

It's in my linux-next from yesterday, but any tegra-* with a "pinmux" node
will do the illustration I think?

quoted

Is the DT machinery really incapable of specifying
the device name to anything else than the bus name?
Can't you do this with AUX_DATA()? I've seen that done in the
past. For example you do:

OF_DEV_AUXDATA("st,nomadik-gpio", 0x8012e000, "gpio.0", NULL),

Can't you just:
OF_DEV_AUXDATA("stericsson,nmk_pinctrl", 0, "pinctrl-db8500", NULL),

And it will happily assign the "pinctrl-db8500" name to it's instantiated
device?

Yes, this will work, see option 'b' above.

OK! Go for it.

Linus Walleij