dt-bindings: dipslay/panel: describe panels using Focaltech OTA7290B

Add schema for the panels using Focaltech OTA7290B controller. For now
there is only one such panel, from the Waveshare 8.8 DSI TOUCH-A kit.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Link: https://patch.msgid.link/20260413-waveshare-dsi-touch-v3-5-3aeb53022c32@oss.qualcomm.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>

Documentation/devicetree/bindings/display/panel/focaltech,ota7290b.yaml

@@ -0,0 +1,70 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/panel/focaltech,ota7290b.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Focaltech OTA7290B DSI panels
+
+maintainers:
+  - Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
+
+allOf:
+  - $ref: panel-common.yaml#
+
+properties:
+  compatible:
+    const: waveshare,8.8-dsi-touch-a
+
+  reg:
+    maxItems: 1
+
+  vdd-supply:
+    description: supply regulator for VDD, usually 3.3V
+
+  vdda-supply:
+    description: supply regulator for VDDA, 7-10V
+
+  vcc-supply:
+    description: supply regulator for VCCIO, usually 1.5V
+
+  reset-gpios: true
+  backlight: true
+  rotation: true
+  port: true
+
+required:
+  - compatible
+  - reg
+  - vdd-supply
+  - vcc-supply
+  - reset-gpios
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    dsi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        panel@0 {
+            compatible = "waveshare,8.8-dsi-touch-a";
+            reg = <0>;
+            vdd-supply = <&vdd>;
+            vcc-supply = <&vccio>;
+            reset-gpios = <&gpio 1 GPIO_ACTIVE_HIGH>;
+            backlight = <&backlight>;
+
+            port {
+                endpoint {
+                    remote-endpoint = <&mipi_out_panel>;
+                };
+            };
+        };
+    };
+
+...
+