In the process of porting boards to devicetree implemenation, we should
keep information about external circuitry where they belong - the
individual drivers.

This patch adds a way to specify a GPIO to drive the (optional) external
pull-up logic, rather than using a function pointer for that.
Signed-off-by: NDaniel Mack <zonque@gmail.com>
Acked-by: NEvgeniy Polyakov <zbr@ioremap.net>
Acked-by: NVille Syrjälä <syrjala@sci.fi>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>