[PATCH v4 13/18] dt-bindings: usb-switch: Extend for DisplayPort altmode

[Stephen Boyd]

Extend the usb-switch binding to support DisplayPort (DP) alternate
modes. A third port for the DP signal is necessary when a mode-switch is
muxing USB and DP together onto a usb type-c connector. Add data-lanes
to the usbc output node to allow a device using this binding to remap
the data lanes on the output. Add an example to show how this new port
can be used.

Reviewed-by: Rob Herring (Arm) <robh at kernel.org>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt at linaro.org>
Cc: Conor Dooley <conor+dt at kernel.org>
Cc: Benson Leung <bleung at chromium.org>
Cc: Guenter Roeck <groeck at chromium.org>
Cc: Prashant Malani <pmalani at chromium.org>
Cc: Tzung-Bi Shih <tzungbi at kernel.org>
Cc: <devicetree at vger.kernel.org>
Cc: <chrome-platform at lists.linux.dev>
Cc: Pin-yen Lin <treapking at chromium.org>
Signed-off-by: Stephen Boyd <swboyd at chromium.org>
---
 .../devicetree/bindings/usb/usb-switch.yaml   | 89 +++++++++++++++++++
 1 file changed, 89 insertions(+)

diff --git a/Documentation/devicetree/bindings/usb/usb-switch.yaml b/Documentation/devicetree/bindings/usb/usb-switch.yaml
index f5dc7e23b134..816f295f322f 100644
--- a/Documentation/devicetree/bindings/usb/usb-switch.yaml
+++ b/Documentation/devicetree/bindings/usb/usb-switch.yaml
@@ -52,6 +52,14 @@ properties:
           endpoint:
             $ref: '#/$defs/usbc-in-endpoint'
 
+      port at 2:
+        $ref: /schemas/graph.yaml#/$defs/port-base
+        unevaluatedProperties: false
+
+        properties:
+          endpoint:
+            $ref: '#/$defs/dp-endpoint'
+
 oneOf:
   - required:
       - port
@@ -65,6 +73,19 @@ $defs:
     $ref: /schemas/graph.yaml#/$defs/endpoint-base
     description: Super Speed (SS) output endpoint to a type-c connector
     unevaluatedProperties: false
+    properties:
+      data-lanes:
+        $ref: /schemas/types.yaml#/definitions/uint32-array
+        description: |
+          An array of physical USB Type-C data lane indexes.
+          - 0 is SSRX1 lane
+          - 1 is SSTX1 lane
+          - 2 is SSTX2 lane
+          - 3 is SSRX2 lane
+        minItems: 4
+        maxItems: 4
+        items:
+          maximum: 3
 
   usbc-in-endpoint:
     $ref: /schemas/graph.yaml#/$defs/endpoint-base
@@ -79,7 +100,75 @@ $defs:
         items:
           maximum: 8
 
+  dp-endpoint:
+    $ref: /schemas/graph.yaml#/$defs/endpoint-base
+    description: DisplayPort (DP) input from the DP PHY
+    unevaluatedProperties: false
+    properties:
+      data-lanes:
+        $ref: /schemas/types.yaml#/definitions/uint32-array
+        description: |
+          An array of physical DP data lane indexes
+          - 0 is DP ML0 lane
+          - 1 is DP ML1 lane
+          - 2 is DP ML2 lane
+          - 3 is DP ML3 lane
+        oneOf:
+          - items:
+              - const: 0
+              - const: 1
+          - items:
+              - const: 0
+              - const: 1
+              - const: 2
+              - const: 3
+
 examples:
+  # A USB + DP mode and orientation switch which muxes DP altmode
+  # and USB onto a usb-c-connector node.
+  - |
+    device {
+      mode-switch;
+      orientation-switch;
+
+      ports {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        port at 0 {
+          reg = <0>;
+          #address-cells = <1>;
+          #size-cells = <0>;
+
+          endpoint {
+            remote-endpoint = <&usb_c_connector>;
+            data-lanes = <0 1 2 3>;
+          };
+        };
+
+        port at 1 {
+          reg = <1>;
+          #address-cells = <1>;
+          #size-cells = <0>;
+
+          endpoint {
+            remote-endpoint = <&usb_ss_phy>;
+          };
+        };
+
+        port at 2 {
+          reg = <2>;
+          #address-cells = <1>;
+          #size-cells = <0>;
+
+          endpoint {
+            remote-endpoint = <&dp_phy>;
+            data-lanes = <0 1 2 3>;
+          };
+        };
+      };
+    };
+
   # A USB orientation switch which flips the pin orientation
   # for a usb-c-connector node.
   - |
-- 
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