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From: David Brownell <david-b@pacbell.net>
To: lvcargnini@gmail.com
Cc: linux-omap@vger.kernel.org
Subject: Re: GPIO issue
Date: Tue, 15 Apr 2008 15:55:15 -0700	[thread overview]
Message-ID: <200804151555.15722.david-b@pacbell.net> (raw)
In-Reply-To: <ae36f8040804151539t50ecece8v867977c7fe7f7578@mail.gmail.com>

On Tuesday 15 April 2008, Luís Vitório Cargnini wrote:
> 
> excuse me now I saw I just put the wrong value in  set_direction
>   omap_set_gpio_direction(8,1);
> 
> must be
>   omap_set_gpio_direction(8,0);

This is one of *many* reasons to avoid using those
legacy GPIO calls.  If you had written

	gpio_direction_input(8)

instead of that first call, the issue would have been obvious.  :)

	if (gpio_request(8, "signal_name") == 0)
		gpio_direction_output(8, 1 /* initial value */);
	else
		/* ERROR */ ;

Note that /sys/kernel/debug/gpio shows GPIO status,
assuming you have debugfs mounted in the normal way.

- Dave
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  reply	other threads:[~2008-04-15 22:55 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-04-15 22:29 GPIO issue Luís Vitório Cargnini
2008-04-15 22:39 ` Luís Vitório Cargnini
2008-04-15 22:55   ` David Brownell [this message]
     [not found]     ` <ae36f8040804151600j2319929epeb6a9e54db28d2ea@mail.gmail.com>
2008-04-15 23:04       ` David Brownell

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