Convert Altera SoC bindings to DT schema format using json-schema.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
---
 .../devicetree/bindings/arm/altera.txt        | 14 -------------
 .../devicetree/bindings/arm/altera.yaml       | 20 +++++++++++++++++++
 2 files changed, 20 insertions(+), 14 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/arm/altera.txt
 create mode 100644 Documentation/devicetree/bindings/arm/altera.yaml

diff --git a/Documentation/devicetree/bindings/arm/altera.txt b/Documentation/devicetree/bindings/arm/altera.txt
deleted file mode 100644
index 558735aacca8..000000000000
--- a/Documentation/devicetree/bindings/arm/altera.txt
+++ /dev/null

@@ -1,14 +0,0 @@
-Altera's SoCFPGA platform device tree bindings
----------------------------------------------
-
-Boards with Cyclone 5 SoC:
-Required root node properties:
-compatible = "altr,socfpga-cyclone5", "altr,socfpga";
-
-Boards with Arria 5 SoC:
-Required root node properties:
-compatible = "altr,socfpga-arria5", "altr,socfpga";
-
-Boards with Arria 10 SoC:
-Required root node properties:
-compatible = "altr,socfpga-arria10", "altr,socfpga";

diff --git a/Documentation/devicetree/bindings/arm/altera.yaml b/Documentation/devicetree/bindings/arm/altera.yaml
new file mode 100644
index 000000000000..49e0362ddc11
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/altera.yaml

@@ -0,0 +1,20 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/arm/altera.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Altera's SoCFPGA platform device tree bindings
+
+maintainers:
+  - Dinh Nguyen <dinguyen@kernel.org>
+
+properties:
+  compatible:
+    items:
+      - enum:
+        - altr,socfpga-cyclone5
+        - altr,socfpga-arria5
+        - altr,socfpga-arria10
+      - const: altr,socfpga
+...