[PATCH 5/8] pinctrl-tz1090: add TZ1090 pinctrl driver

[Linus Walleij]

On Fri, May 3, 2013 at 5:06 PM, James Hogan <james.hogan at imgtec.com> wrote:
> [me]
>> Thus this part of the problem (poking that "select" bit)
>> should be handled by the pinmux part of the driver.
>>
>> The pinconf part does not need to know about it.
>
> Okay, so how would you recommend handling the case of a pin in a muxing
> pingroup that shouldn't be put into peripheral mode?
>
> E.g. imagine an 18bit display is wired to the (24bit) tft pins (which
> are muxed as a group to "tft" function), and the least significant tft
> pins are used as GPIOs to control something like board power supplies.
>
> Without using pinconf I think the muxing pingroups would have to overlap
> like below (is that acceptable?):

I don't know if I understand your example correctly but are you after
this part of the documentation from Documentation/pinctrl.txt:

Pinmux conventions
==================
(...)
  It is possible to map several groups to the same combination of device,
  pin controller and function. This is for cases where a certain function on
  a certain pin controller may use different sets of pins in different
  configurations.

Yours,
Linus Walleij