pinctrl: generic: Add bi-directional and output-enable

Add bi-directional and output-enable pin configuration properties.

bi-directional allows to specify when a pin shall operate in input and
output mode at the same time. This is particularly useful in platforms
where input and output buffers have to be manually enabled.

output-enable is just syntactic sugar to specify that a pin shall
operate in output mode, ignoring the provided argument.
This pairs with input-enable pin configuration option.

Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
index f01d154..71a3c13 100644
--- a/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
+++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
@@ -247,6 +247,7 @@
 bias-pull-up		- pull up the pin
 bias-pull-down		- pull down the pin
 bias-pull-pin-default	- use pin-default pull state
+bi-directional		- pin supports simultaneous input/output operations
 drive-push-pull		- drive actively high and low
 drive-open-drain	- drive with open drain
 drive-open-source	- drive with open source
@@ -259,6 +260,7 @@
 power-source		- select between different power supplies
 low-power-enable	- enable low power mode
 low-power-disable	- disable low power mode
+output-enable		- enable output on pin regardless of output value
 output-low		- set the pin to output mode with low level
 output-high		- set the pin to output mode with high level
 slew-rate		- set the slew rate