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From: Bill Gatliff <bgat@billgatliff.com>
To: Ayman El-Khashab <ayman@elkhashab.com>
Cc: linuxppc-dev@ozlabs.org
Subject: Re: How to set GPIO state in the dts or in platform
Date: Tue, 05 Jan 2010 22:38:50 -0600	[thread overview]
Message-ID: <4B4413DA.7010704@billgatliff.com> (raw)
In-Reply-To: <4B440EDC.3060805@elkhashab.com>

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

  reply	other threads:[~2010-01-06  4:38 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-01-06  4:17 How to set GPIO state in the dts or in platform Ayman El-Khashab
2010-01-06  4:38 ` Bill Gatliff [this message]
2010-01-06  5:08   ` Ayman El-Khashab
2010-01-06 15:16     ` Bill Gatliff

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