dt-bindings: Remove plain text OF graph binding
Rob Herring
maintainerPATCH 1/1 dt-bindings: Remove plain text OF graph binding
From: Sameer Pujar <[email protected]>
A schema for the OF graph binding has been added to the dt-schema repo based on graph.txt contents. Let's replace graph.txt now duplicated contents with a reference to the schema.
For users of the graph binding, they should reference to the graph schema from either 'ports' or 'port' property:
properties:
ports:
$ref: /schemas/graph.yaml#/properties/ports
properties:
port@0:
$ref: /schemas/graph.yaml#/properties/port
description: What data this port has
...Or:
properties:
port:
description: What data this port has
$ref: /schemas/graph.yaml#/properties/port
Cc Sameer Pujar <[email protected]>
Acked-by Philipp Zabel <[email protected]>
Reviewed-by Sam Ravnborg <[email protected]>
Reviewed-by Laurent Pinchart <[email protected]>
[robh: moved graph.yaml to dt-schema repo, expanded commit msg]
Signed-off-by Rob Herring <[email protected]>
--- Documentation/devicetree/bindings/graph.txt | 129 +------------------- 1 file changed, 1 insertion(+), 128 deletions(-)
Documentation/devicetree/bindings/graph.txt +1 -128
@@ -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
Signature · 1 line
2.27.0
Quoted 36 lines · Rob Herring
External email: Use caution opening links or attachments
From: Sameer Pujar <[email protected]>
A schema for the OF graph binding has been added to the dt-schema repo based on graph.txt contents. Let's replace graph.txt now duplicated contents with a reference to the schema.
For users of the graph binding, they should reference to the graph schema from either 'ports' or 'port' property:
properties:
ports: $ref: /schemas/graph.yaml#/properties/ports properties: port@0: $ref: /schemas/graph.yaml#/properties/port description: What data this port has ...Or:
properties:
port:
description: What data this port has
$ref: /schemas/graph.yaml#/properties/portCc Sameer Pujar <[email protected]>Acked-by Philipp Zabel <[email protected]>Reviewed-by Sam Ravnborg <[email protected]>Reviewed-by Laurent Pinchart <[email protected]>[robh: moved graph.yaml to dt-schema repo, expanded commit msg]Signed-off-by Rob Herring <[email protected]>
Quoted 3 lines
--- Documentation/devicetree/bindings/graph.txt | 129 +------------------- 1 file changed, 1 insertion(+), 128 deletions(-)
Acked-by Sameer Pujar <[email protected]>