[PATCH 1/2] dt-bindings: Convert graph bindings to json-schema

[Sameer Pujar <spujar@nvidia.com>]

Convert device tree bindings of graph to YAML format.

Signed-off-by: Sameer Pujar <spujar@nvidia.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
---
 Documentation/devicetree/bindings/graph.txt  | 128 ------------------
 Documentation/devicetree/bindings/graph.yaml | 188 +++++++++++++++++++++++++++
 2 files changed, 188 insertions(+), 128 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/graph.txt
 create mode 100644 Documentation/devicetree/bindings/graph.yaml

diff --git a/Documentation/devicetree/bindings/graph.txt b/Documentation/devicetree/bindings/graph.txt
deleted file mode 100644
index 0415e2c..0000000
--- a/Documentation/devicetree/bindings/graph.txt
+++ /dev/null
@@ -1,128 +0,0 @@
-Common bindings for device graphs
-
-General concept
----------------
-
-The hierarchical organisation of the device tree is well suited to describe
-control flow to devices, but there can be more complex connections between
-devices that work together to form a logical compound device, following an
-arbitrarily complex graph.
-There already is a simple directed graph between devices tree nodes using
-phandle properties pointing to other nodes to describe connections that
-can not be inferred from device tree parent-child relationships. The device
-tree graph bindings described herein abstract more complex devices that can
-have multiple specifiable ports, each of which can be linked to one or more
-ports of other devices.
-
-These common bindings do not contain any information about the direction or
-type of the connections, they just map their existence. Specific properties
-may be described by specialized bindings depending on the type of connection.
-
-To see how this binding applies to video pipelines, for example, see
-Documentation/devicetree/bindings/media/video-interfaces.txt.
-Here the ports describe data interfaces, and the links between them are
-the connecting data buses. A single port with multiple connections can
-correspond to multiple devices being connected to the same physical bus.
-
-Organisation of ports and endpoints
------------------------------------
-
-Ports are described by child 'port' nodes contained in the device node.
-Each port node contains an 'endpoint' subnode for each remote device port
-connected to this port. If a single port is connected to more than one
-remote device, an 'endpoint' child node must be provided for each link.
-If more than one port is present in a device node or there is more than one
-endpoint at a port, or a port node needs to be associated with a selected
-hardware interface, a common scheme using '#address-cells', '#size-cells'
-and 'reg' properties is used to number the nodes.
-
-device {
-        ...
-        #address-cells = <1>;
-        #size-cells = <0>;
-
-        port@0 {
-	        #address-cells = <1>;
-	        #size-cells = <0>;
-		reg = <0>;
-
-                endpoint@0 {
-			reg = <0>;
-			...
-		};
-                endpoint@1 {
-			reg = <1>;
-			...
-		};
-        };
-
-        port@1 {
-		reg = <1>;
-
-		endpoint { ... };
-	};
-};
-
-All 'port' nodes can be grouped under an optional 'ports' node, which
-allows to specify #address-cells, #size-cells properties for the 'port'
-nodes independently from any other child device nodes a device might
-have.
-
-device {
-        ...
-        ports {
-                #address-cells = <1>;
-                #size-cells = <0>;
-
-                port@0 {
-                        ...
-                        endpoint@0 { ... };
-                        endpoint@1 { ... };
-                };
-
-                port@1 { ... };
-        };
-};
-
-Links between endpoints
------------------------
-
-Each endpoint should contain a 'remote-endpoint' phandle property that points
-to the corresponding endpoint in the port of the remote device. In turn, the
-remote endpoint should contain a 'remote-endpoint' property. If it has one, it
-must not point to anything other than the local endpoint. Two endpoints with
-their 'remote-endpoint' phandles pointing at each other form a link between the
-containing ports.
-
-device-1 {
-        port {
-                device_1_output: endpoint {
-                        remote-endpoint = <&device_2_input>;
-                };
-        };
-};
-
-device-2 {
-        port {
-                device_2_input: endpoint {
-                        remote-endpoint = <&device_1_output>;
-                };
-        };
-};
-
-Required properties
--------------------
-
-If there is more than one 'port' or more than one 'endpoint' node or 'reg'
-property present in the port and/or endpoint nodes then the following
-properties are required in a relevant parent node:
-
- - #address-cells : number of cells required to define port/endpoint
-                    identifier, should be 1.
- - #size-cells    : should be zero.
-
-Optional endpoint properties
-----------------------------
-
-- remote-endpoint: phandle to an 'endpoint' subnode of a remote device node.
-
diff --git a/Documentation/devicetree/bindings/graph.yaml b/Documentation/devicetree/bindings/graph.yaml
new file mode 100644
index 0000000..33a6908
--- /dev/null
+++ b/Documentation/devicetree/bindings/graph.yaml
@@ -0,0 +1,188 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/graph.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Common bindings for device graphs
+
+description: |
+  The hierarchical organisation of the device tree is well suited to describe
+  control flow to devices, but there can be more complex connections between
+  devices that work together to form a logical compound device, following an
+  arbitrarily complex graph.
+  There already is a simple directed graph between devices tree nodes using
+  phandle properties pointing to other nodes to describe connections that
+  can not be inferred from device tree parent-child relationships. The device
+  tree graph bindings described herein abstract more complex devices that can
+  have multiple specifiable ports, each of which can be linked to one or more
+  ports of other devices.
+
+  These common bindings do not contain any information about the direction or
+  type of the connections, they just map their existence. Specific properties
+  may be described by specialized bindings depending on the type of connection.
+
+  To see how this binding applies to video pipelines, for example, see
+  Documentation/devicetree/bindings/media/video-interfaces.txt.
+  Here the ports describe data interfaces, and the links between them are
+  the connecting data buses. A single port with multiple connections can
+  correspond to multiple devices being connected to the same physical bus.
+
+maintainers:
+  - Philipp Zabel <p.zabel@pengutronix.de>
+
+properties:
+  port:
+    type: object
+    description: |
+      If there is more than one endpoint node or 'reg' property present in
+      endpoint nodes then '#address-cells' and '#size-cells' properties are
+      required.
+
+    properties:
+      "#address-cells":
+          const: 1
+
+      "#size-cells":
+          const: 0
+
+      reg:
+        maxItems: 1
+
+    patternProperties:
+      "^endpoint(@[0-9a-f]+)?$":
+        type: object
+        properties:
+          reg:
+            maxItems: 1
+
+          remote-endpoint:
+            description: |
+              phandle to an 'endpoint' subnode of a remote device node.
+            $ref: /schemas/types.yaml#/definitions/phandle
+
+    additionalProperties: false
+
+  ports:
+    type: object
+    description: |
+      If there is more than one port node or 'reg' property present in port
+      nodes then '#address-cells' and '#size-cells' properties are required.
+      In such cases all port nodes can be grouped under 'ports' independently
+      from any other child device nodes a device might have.
+
+    properties:
+      "#address-cells":
+        const: 1
+
+      "#size-cells":
+        const: 0
+
+    patternProperties:
+      "^port(@[0-9a-f]+)?$":
+        $ref: "#/properties/port"
+
+    additionalProperties: false
+
+examples:
+  # Organisation of ports and endpoints:
+  #
+  # Ports are described by child 'port' nodes contained in the device node.
+  # Each port node contains an 'endpoint' subnode for each remote device port
+  # connected to this port. If a single port is connected to more than one
+  # remote device, an 'endpoint' child node must be provided for each link.
+  # If more than one port is present in a device node or there is more than
+  # one endpoint at a port, or a port node needs to be associated with a
+  # selected hardware interface, a common scheme using '#address-cells',
+  # '#size-cells' and 'reg' properties is used to number the nodes.
+  - |
+    device {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        port@0 {
+            #address-cells = <1>;
+            #size-cells = <0>;
+            reg = <0>;
+
+            endpoint@0 {
+                reg = <0>;
+                // ...
+            };
+            endpoint@1 {
+                reg = <1>;
+                // ...
+            };
+        };
+
+        port@1 {
+            reg = <1>;
+
+            endpoint {
+                // ...
+            };
+        };
+    };
+
+  # All 'port' nodes can be grouped under an optional 'ports' node, which
+  # allows to specify #address-cells, #size-cells properties for the 'port'
+  # nodes independently from any other child device nodes a device might
+  # have.
+  - |
+    device {
+        // ...
+        ports {
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            port@0 {
+                #address-cells = <1>;
+                #size-cells = <0>;
+                reg = <0>;
+                // ...
+
+                endpoint@0 {
+                    reg = <0>;
+                    // ...
+                };
+                endpoint@1 {
+                    reg = <1>;
+                    // ...
+                };
+            };
+
+            port@1 {
+                #address-cells = <1>;
+                #size-cells = <0>;
+                reg = <1>;
+                // ...
+            };
+        };
+    };
+
+  # Links between endpoints:
+  #
+  # Each endpoint should contain a 'remote-endpoint' phandle property that
+  # points to the corresponding endpoint in the port of the remote device.
+  # In turn, the remote endpoint should contain a 'remote-endpoint' property.
+  # If it has one, it must not point to anything other than the local endpoint.
+  # Two endpoints with their 'remote-endpoint' phandles pointing at each other
+  # form a link between the containing ports.
+  - |
+    device-1 {
+        port {
+            device_1_output: endpoint {
+                remote-endpoint = <&device_2_input>;
+            };
+        };
+    };
+
+    device-2 {
+        port {
+            device_2_input: endpoint {
+                remote-endpoint = <&device_1_output>;
+            };
+        };
+    };
+
+...
-- 
2.7.4