Re: [PATCH 1/3] gpiolib: add gpio_set_direction()

[Andres Salomon <dilinger@collabora.co.uk>]

On Fri, 26 Feb 2010 17:26:24 -0600
Ben Gardner <gardner.ben@gmail.com> wrote:

> Combine gpio_direction_input() and gpio_direction_output() into
> gpio_set_direction().
> Add 'none' and 'inout' directions to the sysfs interface.
> 
> Signed-off-by: Ben Gardner <gardner.ben@gmail.com>
> CC: Andres Salomon <dilinger@collabora.co.uk>
> CC: Andrew Morton <akpm@linux-foundation.org>
> CC: David Brownell <dbrownell@users.sourceforge.net>
> CC: Jani Nikula <ext-jani.1.nikula@nokia.com>
> ---
>  drivers/gpio/gpiolib.c     |  123 ++++++++++++++++++++++----------------------
>  include/asm-generic/gpio.h |    6 ++
>  include/linux/gpio.h       |    5 ++
>  3 files changed, 73 insertions(+), 61 deletions(-)
> 
[...]
> diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
> index 485eeb6..17c7642 100644
> --- a/include/asm-generic/gpio.h
> +++ b/include/asm-generic/gpio.h
> @@ -41,6 +41,8 @@ struct module;
>   *	enabling module power and clock; may sleep
>   * @free: optional hook for chip-specific deactivation, such as
>   *	disabling module power and clock; may sleep
> + * @set_direction: configures signal "offset" as "direction" (0-3, bit0=input,
> + *	bit1=output) or returns error


How about something like the following for set_direction, so we're not
comparing magic bits?

/* gpio direction flags */
#define GPIO_DIR_NONE 0 
#define	GPIO_DIR_INPUT (1 << 0)
#define	GPIO_DIR_OUTPUT (1 << 1)