1. Add pseudo-ovl definition file for mt8195 display.
2. Add mediatek,pseudo-ovl.yaml to decribe pseudo-ovl module in details.

Signed-off-by: Nancy.Lin <redacted>
---
 .../display/mediatek/mediatek,disp.yaml       |   5 +
 .../display/mediatek/mediatek,pseudo-ovl.yaml | 105 ++++++++++++++++++
 2 files changed, 110 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/mediatek/mediatek,pseudo-ovl.yaml

diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,disp.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,disp.yaml
index aac1796e3f6b..bb6d28572b48 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,disp.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,disp.yaml

@@ -230,6 +230,11 @@ properties:
       - items:
           - const: mediatek,mt8173-disp-od

+      # PSEUDO-OVL: see Documentation/devicetree/bindings/display/mediatek/mediatek,pseudo-ovl.yaml
+      # for details.
+      - items:
+          - const: mediatek,mt8195-disp-pseudo-ovl
+
   reg:
     description: Physical base address and length of the function block register space.

diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,pseudo-ovl.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,pseudo-ovl.yaml
new file mode 100644
index 000000000000..9059d96ce70e
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,pseudo-ovl.yaml

@@ -0,0 +1,105 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/mediatek/mediatek,pseudo-ovl.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: mediatek pseudo ovl Device Tree Bindings
+
+maintainers:
+  - CK Hu <ck.hu@mediatek.com>
+  - Nancy.Lin <nancy.lin@mediatek.com>
+
+description: |
+  The Mediatek pseudo ovl function block is composed of eight RDMA and
+  four MERGE devices. It's encapsulated as an overlay device, which supports
+  4 layers.
+
+properties:
+  compatible:
+    oneOf:
+      # pseudo ovl controller
+      - items:
+          - const: mediatek,mt8195-disp-pseudo-ovl
+      # RDMA: read DMA
+      - items:
+          - const: mediatek,mt8195-vdo1-rdma
+      # MERGE: merge streams from two RDMA sources
+      - items:
+          - const: mediatek,mt8195-vdo1-merge
+  reg:
+    maxItems: 1
+  interrupts:
+    maxItems: 1
+  iommus:
+    description: The compatible property is DMA function blocks.
+      Should point to the respective IOMMU block with master port as argument,
+      see Documentation/devicetree/bindings/iommu/mediatek,iommu.yaml for
+      details.
+    maxItems: 1
+  clocks:
+    maxItems: 2
+  clock-names:
+    maxItems: 2
+  power-domains:
+    maxItems: 1
+  mediatek,gce-client-reg:
+    $ref: /schemas/types.yaml#/definitions/phandle-array
+    description: The register of display function block to be set by gce.
+      There are 4 arguments in this property, gce node, subsys id, offset and
+      register size. The subsys id is defined in the gce header of each chips
+      include/include/dt-bindings/gce/<chip>-gce.h, mapping to the register of
+      display function block.
+
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            const:
+              - mediatek,mt8195-vdo1-merge
+
+    then:
+      properties:
+        clocks:
+          items:
+            - description: merge clock
+            - description: merge async clock
+        clock-names:
+          items:
+            - const: merge
+            - const: merge_async
+
+required:
+  - compatible
+  - reg
+  - clocks
+
+additionalProperties: false
+
+examples:
+  - |
+
+    vdo1_rdma@1c104000 {
+            compatible = "mediatek,mt8195-vdo1-rdma",
+                         "mediatek,mt8195-disp-pseudo-ovl";