[PATCH 1/4] dt-bindings: usb-connector: Add support for Type-C alternate-modes

[Hans de Goede <hdegoede@redhat.com>]

This commit adds the minimum bindings required to allow describing which
altmodes a port supports. Currently this is limited to just specifying:

1. The svid, which is the id of the altmode, e.g. displayport altmode has
a svid of 0xff01.

2. The vdo, a 32 bit integer, typically used as a bitmask describing the
capabilities of the altmode, the bits in the vdo are specified in the
specification of the altmode, the dt-binding simply refers to the
specification as that is the canonical source of the meaning of the bits.

Later on we may want to extend the binding with extra properties specific
to some altmode, but for now this is sufficient to e.g. hook up
displayport alternate-mode.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Note I hope I got the yaml correct, this is my first time writing a
dt-binding in the new yaml style. I did run:
make dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/connector/usb-connector.yaml
and that was happy.
---
 .../bindings/connector/usb-connector.yaml     | 21 +++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/Documentation/devicetree/bindings/connector/usb-connector.yaml b/Documentation/devicetree/bindings/connector/usb-connector.yaml
index 9bd52e63c935..389e800c9fe8 100644
--- a/Documentation/devicetree/bindings/connector/usb-connector.yaml
+++ b/Documentation/devicetree/bindings/connector/usb-connector.yaml
@@ -119,6 +119,27 @@ properties:
       offer the power, Capability Mismatch is set. Required for power sink and
       power dual role.
 
+  altmodes:
+    description:
+      List of child nodes that specify the altmodes supported by the
+      "usb-c-connector". The child nodes must be named foo-altmode, e.g.
+      "displayport-altmode".
+
+    patternProperties:
+      "^.*-altmode$":
+        type: object
+        description: The altmodes node has 1 child-node per supported altmode.
+        properties:
+          svid:
+            description: USB Type-C / PD altmode-svid, see the USB specifications
+              for details.
+          vdo:
+            description: USB Type-C / PD altmode-vdo, see the USB specifications
+              for details.
+        required:
+          - svid
+          - vdo
+
   ports:
     description: OF graph bindings (specified in bindings/graph.txt) that model
       any data bus to the connector unless the bus is between parent node and
-- 
2.26.2