[PATCHv2] Input: omap4-keypad: Add pinctrl support

Linus Walleij linus.walleij at linaro.org
Tue Oct 30 10:11:57 EDT 2012


On Tue, Oct 30, 2012 at 12:49 PM, Felipe Balbi <balbi at ti.com> wrote:
> On Tue, Oct 30, 2012 at 11:24:10AM +0000, Mark Brown wrote:

>> We need some place to put the SoC integration; power domains seem like
>> the obvious place to me but YMMV.  Nothing about having this out of the
>
> except that pin muxing has nothing to do with power domain. To me that
> sounds like an abuse of the API.

It could be renamed to "power resources" or something as long as
it's related to resource handling related to the PM calls.

But I worry that it violates the Unix principle to do one thing and one
thing only.

A device power resource framework goes in the opposite direction,
trying to do a lot of unrelated things in a central place as opposed
to distributing the task.

>> drivers requires that this be done by individual subsystems in isolation
>> from each other.  Half the point here is that for the reusable IPs this
>> stuff often isn't driver specific at all, it's often more about the SoC
>> integration than it is about the driver and so you'll get a consistent
>> pattern for most IPs on the SoC.
>
> and all of that SoC-specific detail is already hidden behind power
> domains, runtime PM, pinctrl, clk API, regulator framework, etc.

I agree.

pinctrl has already done a fair job at trying to be abstract in the
states requested from the core, in <linux/pinctrl/pinctrl-state.h>.

And I accept the idea to  try to centralize more as well, maybe
as a helpful struct and some inlines for the pinctrl core. I think
this is enough, and pushing all handles into central code creates
a problem elsewhere.

(But I'm not so certain ... so I might just
change opinion one of those days depending on what
arguments will be made.)

Yours,
Linus Walleij



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