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Date: Tue, 05 Jan 2010 22:38:50 -0600
From: Bill Gatliff <bgat@billgatliff.com>
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To: Ayman El-Khashab <ayman@elkhashab.com>
Subject: Re: How to set GPIO state in the dts or in platform
References: <4B440EDC.3060805@elkhashab.com>
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Ayman El-Khashab wrote:
> I've got a custom board akin to the walnut.  I've successfully got
> u-boot,
> the kernel, and a working filesystem.  The only thing I lack is a
> clear idea
> of how to set a GPIO.

Isn't that the "flags" parameter, e.g.:

gpios = <phandle gpioid flags>

?

If you are passing a 0 for the flags, try a 1.  I know of at least one
driver that interprets that to mean a polarity inversion.  Maybe you'll
get lucky.  :)


b.g.

-- 
Bill Gatliff
Embedded systems training and consulting
http://billgatliff.com
bgat@billgatliff.com