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

Haojian Zhuang haojian.zhuang at gmail.com
Wed Apr 20 10:26:14 EDT 2011


On Tue, Apr 19, 2011 at 4:51 PM, Kyungmin Park <kmpark at infradead.org> wrote:
>>
>> Leaving aside the current input/output and on/off bits I would go for
>> being able to do
>>
>>        gpio_get_property(gpio, GPIO_BIAS, GPIO_BIAS_WHATEVER);
>>        gpio_set_property(gpio, GPIO_BIAS, GPIO_BIAS_WHATEVER_ELSE);
>
> 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.
>
I have a little confusion. In ARM SoC, a lot of pins are used as
multi-functions.

Before suspend, it may be configured as some function that isn't GPIO.
Is it a goal
that avoid declaring gpio_request() for suspend and updating the setting of pin?

Linus,
Are these two patches are post in mailing list? I can't find your
second patch in this
patch series?



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