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SubjectRe: [PATCH v3 1/4] gpiolib: Add "unknown" direction support
Hello,

On Thu, Feb 17, 2011 at 05:03:16PM -0600, Peter Tyser wrote:
> Previously, gpiolib would unconditionally flag all GPIO pins as inputs,
> regardless of their true state. This resulted in all GPIO output pins
> initially being incorrectly identified as "input" in the GPIO sysfs.
>
> Since the direction of GPIOs is not known prior to having their
> direction set, instead set the default direction to "unknown" to prevent
> user confusion. A pin with an "unknown" direction can not be written or
> read via sysfs; it must first be configured as an input or output before
> it can be used.
>
> While we're playing with the direction flag in/out defines, rename them to
> a more descriptive FLAG_DIR_* format.
Would it make sense to reset the state to unknown on gpio_free?

Best regards
Uwe

--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | http://www.pengutronix.de/ |
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