dt-bindings: display: bridge: lt9211: Add Lontium LT9211 bridge driver

Add bindings for Lontium LT9211 Single/Dual-Link DSI/LVDS or Single DPI to
Single-link/Dual-Link DSI/LVDS or Single DPI bridge. This chip is highly
capable at converting formats, but sadly it is also highly undocumented.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: devicetree@vger.kernel.org
To: dri-devel@lists.freedesktop.org
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220419143958.94873-1-marex@denx.de

Documentation/devicetree/bindings/display/bridge/lontium,lt9211.yaml

@@ -0,0 +1,117 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/bridge/lontium,lt9211.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Lontium LT9211 DSI/LVDS/DPI to DSI/LVDS/DPI bridge.
+
+maintainers:
+  - Marek Vasut <marex@denx.de>
+
+description: |
+  The LT9211 are bridge devices which convert Single/Dual-Link DSI/LVDS
+  or Single DPI to Single/Dual-Link DSI/LVDS or Single DPI.
+
+properties:
+  compatible:
+    enum:
+      - lontium,lt9211
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  reset-gpios:
+    maxItems: 1
+    description: GPIO connected to active high RESET pin.
+
+  vccio-supply:
+    description: Regulator for 1.8V IO power.
+
+  ports:
+    $ref: /schemas/graph.yaml#/properties/ports
+
+    properties:
+      port@0:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Primary MIPI DSI port-1 for MIPI input or
+          LVDS port-1 for LVDS input or DPI input.
+
+      port@1:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Additional MIPI port-2 for MIPI input or LVDS port-2
+          for LVDS input. Used in combination with primary
+          port-1 to drive higher resolution displays
+
+      port@2:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Primary MIPI DSI port-1 for MIPI output or
+          LVDS port-1 for LVDS output or DPI output.
+
+      port@3:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Additional MIPI port-2 for MIPI output or LVDS port-2
+          for LVDS output. Used in combination with primary
+          port-1 to drive higher resolution displays.
+
+    required:
+      - port@0
+      - port@2
+
+required:
+  - compatible
+  - reg
+  - vccio-supply
+  - ports
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      hdmi-bridge@3b {
+        compatible = "lontium,lt9211";
+        reg = <0x3b>;
+
+        reset-gpios = <&tlmm 128 GPIO_ACTIVE_HIGH>;
+        interrupts-extended = <&tlmm 84 IRQ_TYPE_EDGE_FALLING>;
+
+        vccio-supply = <&lt9211_1v8>;
+
+        ports {
+          #address-cells = <1>;
+          #size-cells = <0>;
+
+          port@0 {
+            reg = <0>;
+
+            endpoint {
+              remote-endpoint = <&dsi0_out>;
+            };
+          };
+
+          port@2 {
+            reg = <2>;
+
+            endpoint {
+              remote-endpoint = <&panel_in_lvds>;
+            };
+          };
+        };
+      };
+    };
+
+...