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

Linus Walleij linus.ml.walleij at gmail.com
Wed Apr 20 11:13:41 EDT 2011

2011/4/20 Haojian Zhuang <haojian.zhuang at gmail.com>:

> 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?

I refer to that as a totally different use case "pinmux or padmux"
which I think we are better off treating as totally orthogonal to GPIO.

I have loose ideas to break pin/pad muxing into a separate driver
directory under drivers/pinpadmux or something.

Some people inevitably think that GPIO and pin/padmux are
intertwined, but as far as I have seen they are not. However there
may be a cross dependency so that a GPIO driver may need to
export an additional pin/padmux interface or so, e.g we have
a separate chip in I2C which can mux pins...

However this is a separate issue altogether, I think we can assume
pin/padmuxing is in the board code until we have a suitable
solution for a framework for that. (Don't know if I'll be able to write
one though.)

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

I can see it here ... ?

Linus Walleij

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