Add the properties 'skew-delay-input' and 'skew-delay-output' to
specify independent skew delay value for the two pin's directions.
Make the new properties unavailable when the existing property
'skew-delay' is selected.

Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
---
 .../bindings/pinctrl/pincfg-node.yaml         | 22 +++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml b/Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml
index cbfcf215e571d..c3deb103d816b 100644
--- a/Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml
+++ b/Documentation/devicetree/bindings/pinctrl/pincfg-node.yaml
@@ -153,4 +153,26 @@ properties:
       pin. Typically indicates how many double-inverters are
       used to delay the signal.
 
+  skew-delay-input:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      this affects the expected clock skew on input pins.
+      Typically indicates how many double-inverters are used to
+      delay the signal.
+
+  skew-delay-output:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      this affects the expected delay before latching a value to an
+      output pins. Typically indicates how many double-inverters are
+      used to delay the signal.
+
+if:
+  required:
+    - skew-delay
+then:
+  properties:
+    skew-delay-input: false
+    skew-delay-output: false
+
 additionalProperties: true
-- 
2.34.1