[PATCH v4 1/5] dt-bindings: remoteproc: imx_rproc: Add "rpmsg" subnode support

[Shenwei Wang <shenwei.wang@nxp.com>]

Remote processors may announce multiple devices (e.g., I2C, GPIO) over
an RPMSG channel. These devices may require corresponding device tree
nodes, especially when acting as providers, to supply phandles for their
consumers.

Define an RPMSG node to work as a container for a group of RPMSG channels
under the imx_rproc node.

Each subnode within "rpmsg" represents an individual RPMSG channel. The
name of each subnode corresponds to the channel name as defined by the
remote processor.

All remote devices associated with a given channel are defined as child
nodes under the corresponding channel node.

Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com>
---
 .../bindings/remoteproc/fsl,imx-rproc.yaml    | 123 ++++++++++++++++++
 1 file changed, 123 insertions(+)

diff --git a/Documentation/devicetree/bindings/remoteproc/fsl,imx-rproc.yaml b/Documentation/devicetree/bindings/remoteproc/fsl,imx-rproc.yaml
index 57d75acb0b5e..897a16c4f7db 100644
--- a/Documentation/devicetree/bindings/remoteproc/fsl,imx-rproc.yaml
+++ b/Documentation/devicetree/bindings/remoteproc/fsl,imx-rproc.yaml
@@ -84,6 +84,92 @@ properties:
       This property is to specify the resource id of the remote processor in SoC
       which supports SCFW
 
+  rpmsg:
+    type: object
+    additionalProperties: false
+    description:
+      Present a group of RPMSG channel devices.
+
+    properties:
+      rpmsg-io-channel:
+        type: object
+        additionalProperties: false
+        properties:
+          '#address-cells':
+            const: 1
+
+          '#size-cells':
+            const: 0
+
+        patternProperties:
+          "gpio@[0-9a-f]+$":
+            type: object
+            unevaluatedProperties: false
+            properties:
+              compatible:
+                enum:
+                  - fsl,imx-rpmsg-gpio
+
+              reg:
+                maxItems: 1
+
+              "#gpio-cells":
+                const: 2
+
+              gpio-controller: true
+
+              interrupt-controller: true
+
+              "#interrupt-cells":
+                const: 2
+
+            required:
+              - compatible
+              - reg
+              - "#gpio-cells"
+              - "#interrupt-cells"
+
+            allOf:
+              - $ref: /schemas/gpio/gpio.yaml#
+              - $ref: /schemas/interrupt-controller.yaml#
+
+        required:
+          - '#address-cells'
+          - '#size-cells'
+
+      rpmsg-i2c-channel:
+        type: object
+        unevaluatedProperties: false
+        properties:
+          '#address-cells':
+            const: 1
+
+          '#size-cells':
+            const: 0
+
+        patternProperties:
+          "i2c@[0-9a-f]+$":
+            type: object
+            unevaluatedProperties: false
+            properties:
+              compatible:
+                enum:
+                  - fsl,imx-rpmsg-i2c
+
+              reg:
+                maxItems: 1
+
+            required:
+              - compatible
+              - reg
+
+            allOf:
+              - $ref: /schemas/i2c/i2c-controller.yaml#
+
+        required:
+          - '#address-cells'
+          - '#size-cells'
+
 required:
   - compatible
 
@@ -146,5 +232,42 @@ examples:
                 &mu 3 1>;
       memory-region = <&vdev0buffer>, <&vdev0vring0>, <&vdev0vring1>, <&rsc_table>;
       syscon = <&src>;
+
+      rpmsg {
+        rpmsg-io-channel {
+          #address-cells = <1>;
+          #size-cells = <0>;
+
+          gpio@0 {
+            compatible = "fsl,imx-rpmsg-gpio";
+            reg = <0>;
+            gpio-controller;
+            #gpio-cells = <2>;
+            #interrupt-cells = <2>;
+            interrupt-controller;
+            interrupt-parent = <&rpmsg_gpioa>;
+          };
+
+          gpio@1 {
+            compatible = "fsl,imx-rpmsg-gpio";
+            reg = <1>;
+            gpio-controller;
+            #gpio-cells = <2>;
+            #interrupt-cells = <2>;
+            interrupt-controller;
+            interrupt-parent = <&rpmsg_gpiob>;
+          };
+        };
+
+        rpmsg-i2c-channel {
+          #address-cells = <1>;
+          #size-cells = <0>;
+
+          i2c@0 {
+            compatible = "fsl,imx-rpmsg-i2c";
+            reg = <0>;
+          };
+        };
+      };
     };
 ...
-- 
2.43.0