From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Warren <swarren@wwwdotorg.org>
Date: Fri, 25 May 2012 10:27:02 -0600
Subject: [U-Boot] [PATCH v2 5/7] tegra: Implement gpio_early_init() on
	Tamonten
In-Reply-To: <1337953588-20696-5-git-send-email-thierry.reding@avionic-design.de>
References: <1337953588-20696-1-git-send-email-thierry.reding@avionic-design.de>
	<1337953588-20696-5-git-send-email-thierry.reding@avionic-design.de>
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On 05/25/2012 07:46 AM, Thierry Reding wrote:
> The PI4 GPIO is used on Tamonten to reset carrier board peripherals.
> Power sequencing hardware on the carrier pulls the reset low before
> powering up the Tegra, and the CPU is supposed to signal readiness,
> and therefore bring peripherals out of reset by pulling PI4 high.

> +void gpio_early_init(void)
> +{
> +	gpio_request(GPIO_PI4, NULL);
> +	gpio_direction_output(GPIO_PI4, 1);
> +	gpio_free(GPIO_PI4);
> +}

Do you really mean to free the GPIO here?

While gpio_free() does not do this at present, it seems perfectly
reasonable for someone to modify gpio_free() so that instead of leaving
the HW in some random state when free, it actively reprograms the pin to
be an input instead, since that's the most conflict-free setting when
the pin is actively unused.