Hi Linus and Morimoto-san,

On Tuesday 23 September 2014 17:06:28 Linus Walleij wrote:

On Wed, Sep 10, 2014 at 10:55 AM, Laurent Pinchart wrote:

quoted

On Sunday 31 August 2014 22:08:52 Kuninori Morimoto wrote:

quoted

I know we can use "defalt" PFC settings on DT.
But, how to use "defalt" GPIO pin settings on DT ?

We would like to use GPIO 7-17 as Low output,
and do nothing after boot.

From a DT point of view I believe this is supposed to be done by
specifying the output-low or output-high properties in the pinctrl
configuration node. However, these properties are not supported by the PFC
driver, and there's no easy way for the PFC driver to configure GPIOs
handled by a different driver such as the gpio-rcar driver for instance.

Linus, do you have any hindsight on how this should be implemented ?

I have suggested adding GPIO hogs, so that a GPIO node can specify
that some GPIO's specified on the local ship be hogged high or
low at probe. Generic DT bindings and generic code in gpiolib.c.

gpios-hog-high = <....>;
gpios-hog-low = <....>;

How about just a gpios-hog property, with a list of gpio specifiers + flags ? 
That's bikeshedding I suppose.

Morimoto-san, would you like to implement that ? :-)

-- 
Regards,

Laurent Pinchart