[PATCH 1/2] gpio: add pin biasing and drive mode to gpiolib

Kyungmin Park kmpark at infradead.org
Wed Apr 20 08:38:59 EDT 2011

On Wed, Apr 20, 2011 at 9:32 PM, Linus Walleij <linus.walleij at linaro.org> wrote:
> 2011/4/19 Kyungmin Park <kmpark at infradead.org>:
>> One more consideration, not mentioned previous time, is that pin
>> configuration for power down mode.
>> Samsung SoCs has retention GPIO configurations at sleep (suspend)
>> mode. and restore it at resume time.
>> it's need to reduce power and proper operation after suspend.
> Isn't this supposed to be handled by runtime_pm hooks inside
> your GPIO driver rather than by someone else talking to
> the GPIO driver trying to spool/unspool the state from the
> outside in some other place?

It's different from normal gpio input/output pin. It has different
offset and configuration.
As I know, current gpiolib doesn't support it.

Of course these should be handled at board file instead of drivers.

Thank you,
Kyungmin Park
> Or am I getting things backwards now...?
> Yours,
> Linus Walleij

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