@@ -1,128 +1 @@
-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.
-
+This file has moved to graph.yaml in dt-schema repo