[PATCH v1 1/3] dt-bindings: display: st7701: Add Anbernic RG28XX panel

[Hironori KIKUCHI <kikuchan98@gmail.com>]

The RG28XX panel is a panel specific to the Anbernic RG28XX.
It is 2.8 inches in size (diagonally) with a resolution of 480x640.

Signed-off-by: Hironori KIKUCHI <kikuchan98@gmail.com>
---
 .../display/panel/sitronix,st7701.yaml        | 36 +++++++++++++++++--
 1 file changed, 34 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/panel/sitronix,st7701.yaml b/Documentation/devicetree/bindings/display/panel/sitronix,st7701.yaml
index b348f5bf0a9..04f6751ccca 100644
--- a/Documentation/devicetree/bindings/display/panel/sitronix,st7701.yaml
+++ b/Documentation/devicetree/bindings/display/panel/sitronix,st7701.yaml
@@ -22,19 +22,21 @@ description: |
 
 allOf:
   - $ref: panel-common.yaml#
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
 
 properties:
   compatible:
     items:
       - enum:
           - anbernic,rg-arc-panel
+          - anbernic,rg28xx-panel
           - densitron,dmt028vghmcmi-1a
           - elida,kd50t048a
           - techstar,ts8550b
       - const: sitronix,st7701
 
   reg:
-    description: DSI virtual channel used by that screen
+    description: DSI / SPI channel used by that screen
     maxItems: 1
 
   VCC-supply:
@@ -43,6 +45,13 @@ properties:
   IOVCC-supply:
     description: I/O system regulator
 
+  dc-gpios:
+    maxItems: 1
+    description: |
+      Controller data/command selection (D/CX) in 4-line SPI mode.
+      If not set, the controller is in 3-line SPI mode.
+      No effect for DSI.
+
   port: true
   reset-gpios: true
   rotation: true
@@ -57,7 +66,7 @@ required:
   - port
   - reset-gpios
 
-additionalProperties: false
+unevaluatedProperties: false
 
 examples:
   - |
@@ -82,3 +91,26 @@ examples:
             };
         };
     };
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        panel@0 {
+            compatible = "anbernic,rg28xx-panel", "sitronix,st7701";
+            reg = <0>;
+            spi-max-frequency = <3125000>;
+            VCC-supply = <&reg_lcd>;
+            IOVCC-supply = <&reg_lcd>;
+            reset-gpios = <&pio 8 14 GPIO_ACTIVE_HIGH>; /* LCD-RST: PI14 */
+            backlight = <&backlight>;
+
+            port {
+                panel_in_rgb: endpoint {
+                    remote-endpoint = <&tcon_lcd0_out_lcd>;
+                };
+            };
+        };
+    };
-- 
2.45.2