right representation of the pin.
Optional properties:
-- GENERIC_PINCONFIG: generic pinconfig options to use, bias-disable,
-bias-pull-down, bias-pull-up, drive-open-drain, input-schmitt-enable,
-input-debounce.
+- GENERIC_PINCONFIG: generic pinconfig options to use:
+ - bias-disable, bias-pull-down, bias-pull-up, drive-open-drain,
+ input-schmitt-enable, input-debounce
+ - slew-rate: 0 - disabled, 1 - enabled (default)
- atmel,drive-strength: 0 or 1 for low drive, 2 for medium drive and 3 for
high drive. The default value is low drive.