dt-bindings: power: reset: gpio-poweroff: Convert txt bindings to yaml

Convert power-off action connected to the GPIO documentation to the YAML syntax.
Signed-off-by: David Heidelberg <david@ixit.cz>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

Documentation/devicetree/bindings/power/reset/gpio-poweroff.txt

-Driver a GPIO line that can be used to turn the power off.
-
-The driver supports both level triggered and edge triggered power off.
-At driver load time, the driver will request the given gpio line and
-install a handler to power off the system. If the optional properties
-'input' is not found, the GPIO line will be driven in the inactive
-state. Otherwise its configured as an input.
-
-When the power-off handler is called, the gpio is configured as an
-output, and drive active, so triggering a level triggered power off
-condition. This will also cause an inactive->active edge condition, so
-triggering positive edge triggered power off. After a delay of 100ms,
-the GPIO is set to inactive, thus causing an active->inactive edge,
-triggering negative edge triggered power off. After another 100ms
-delay the GPIO is driver active again. If the power is still on and
-the CPU still running after a 3000ms delay, a WARN_ON(1) is emitted.
-
-Required properties:
-- compatible : should be "gpio-poweroff".
-- gpios : The GPIO to set high/low, see "gpios property" in
-  Documentation/devicetree/bindings/gpio/gpio.txt. If the pin should be
-  low to power down the board set it to "Active Low", otherwise set
-  gpio to "Active High".
-
-Optional properties:
-- input : Initially configure the GPIO line as an input. Only reconfigure
-  it to an output when the power-off handler is called. If this optional
-  property is not specified, the GPIO is initialized as an output in its
-  inactive state.
-- active-delay-ms: Delay (default 100) to wait after driving gpio active
-- inactive-delay-ms: Delay (default 100) to wait after driving gpio inactive
-- timeout-ms: Time to wait before asserting a WARN_ON(1). If nothing is
-              specified, 3000 ms is used.
-
-Examples:
-
-gpio-poweroff {
-	compatible = "gpio-poweroff";
-	gpios = <&gpio 4 0>;
-	timeout-ms = <3000>;
-};

Documentation/devicetree/bindings/power/reset/gpio-poweroff.yaml

+# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/power/reset/gpio-poweroff.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: GPIO controlled power off
+
+maintainers:
+  - Sebastian Reichel <sre@kernel.org>
+
+description: >
+  System power off support via a GPIO line. When a shutdown is
+  executed the operating system is expected to switch the GPIO
+  from inactive to active. After a delay (active-delay-ms) it
+  is expected to be switched back to inactive. After another
+  delay (inactive-delay-ms) it is configured as active again.
+  Finally the operating system assumes the power off failed if
+  the system is still running after waiting some time (timeout-ms).
+
+properties:
+  compatible:
+    const: gpio-poweroff
+
+  gpios:
+    maxItems: 1
+
+  input:
+    type: boolean
+    description: >
+      Initially configure the GPIO line as an input. Only reconfigure
+      it to an output when the power-off sequence is initiated. If this optional
+      property is not specified, the GPIO is initialized as an output in its inactive state.
+
+  active-delay-ms:
+    default: 100
+    description: Delay to wait after driving gpio active
+
+  inactive-delay-ms:
+    default: 100
+    description: Delay to wait after driving gpio inactive
+
+  timeout-ms:
+    default: 3000
+    description: Time to wait before assuming the power off sequence failed.
+
+required:
+  - compatible
+  - gpios
+
+additionalProperties: false
+
+examples:
+  - |
+    gpio-poweroff {
+        compatible = "gpio-poweroff";
+        gpios = <&gpio 4 0>;
+        timeout-ms = <3000>;
+    };