[PATCH 3/4] pinctrl: Add support for additional dynamic states

Linus Walleij linus.walleij at linaro.org
Mon Jul 22 19:15:13 EDT 2013


On Fri, Jul 19, 2013 at 9:03 PM, Stephen Warren <swarren at wwwdotorg.org> wrote:
> On 07/19/2013 04:29 AM, Grygorii Strashko wrote:

>> First of all, I'd like to mention that these patches do *not* connect
>> pinctrl to PM runtime, so until driver will call pinctrl_select_state()
>> or pinctrl_pm_select_*() there will be no pins state changes.
>
> Isn't the whole point of the pinctrl_pm_select*() APIs to eventually be
> called automatically by the runtime PM core,

Nah I had no such complete ambitions, just factoring around.

There are examples, such as deactivating a TTY from userspace,
that should result in the pins going to sleep while it may have nothing
to do with runtime PM.

> so that we don't need to
> write code to do this in every single driver, just like we moved the
> call to pinctrl_select_state(default) into the device core so that we
> didn't have to make every device do that manually?

I am pretty convinced that if this dynamic muxing stuff shall be
implemented, it should be a pinctrl subsystem intrinsic optimization
detail and should not be exposed to the outside with all these extra
functions at all. It looks overly complicated to me.

Yours,
Linus Walleij



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