dt-bindings: gpu: Convert aspeed,ast2400-gfx to DT schema

Convert the ASpeed GFX Display Controller binding to DT schema format.
There was a duplicate, incomplete binding in mfd which can be dropped.

Add the missing 'aspeed,ast2600-gfx' compatible and 'syscon' property.

Reviewed-by: Andrew Jeffery <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Rob Herring (Arm) <[e-mail]>

Documentation/devicetree/bindings/gpu/aspeed,ast2400-gfx.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/gpu/aspeed,ast2400-gfx.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ASPEED GFX Display Controller
+
+maintainers:
+  - Joel Stanley <[e-mail]>
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - aspeed,ast2400-gfx
+          - aspeed,ast2500-gfx
+          - aspeed,ast2600-gfx
+      - const: syscon
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  resets:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  memory-region:
+    maxItems: 1
+    description:
+      a reserved-memory region to use for the framebuffer.
+
+  syscon:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description: Phandle to SCU
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - resets
+  - memory-region
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/aspeed-clock.h>
+
+    display@1e6e6000 {
+        compatible = "aspeed,ast2500-gfx", "syscon";
+        reg = <0x1e6e6000 0x1000>;
+        clocks = <&syscon ASPEED_CLK_GATE_D1CLK>;
+        resets = <&syscon ASPEED_RESET_CRT1>;
+        interrupts = <0x19>;
+        memory-region = <&gfx_memory>;
+    };

Documentation/devicetree/bindings/gpu/aspeed-gfx.txt

···
-Device tree configuration for the GFX display device on the ASPEED SoCs
-
-Required properties:
-  - compatible
-    * Must be one of the following:
-      + aspeed,ast2500-gfx
-      + aspeed,ast2400-gfx
-    * In addition, the ASPEED pinctrl bindings require the 'syscon' property to
-      be present
-
-  - reg: Physical base address and length of the GFX registers
-
-  - interrupts: interrupt number for the GFX device
-
-  - clocks: clock number used to generate the pixel clock
-
-  - resets: reset line that must be released to use the GFX device
-
-  - memory-region:
-    Phandle to a memory region to allocate from, as defined in
-    Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
-
-
-Example:
-
-gfx: display@1e6e6000 {
-	compatible = "aspeed,ast2500-gfx", "syscon";
-	reg = <0x1e6e6000 0x1000>;
-	reg-io-width = <4>;
-	clocks = <&syscon ASPEED_CLK_GATE_D1CLK>;
-	resets = <&syscon ASPEED_RESET_CRT1>;
-	interrupts = <0x19>;
-	memory-region = <&gfx_memory>;
-};
-
-gfx_memory: framebuffer {
-	size = <0x01000000>;
-	alignment = <0x01000000>;
-	compatible = "shared-dma-pool";
-	reusable;
-};

Documentation/devicetree/bindings/mfd/aspeed-gfx.txt

···
-* Device tree bindings for Aspeed SoC Display Controller (GFX)
-
-The Aspeed SoC Display Controller primarily does as its name suggests, but also
-participates in pinmux requests on the g5 SoCs. It is therefore considered a
-syscon device.
-
-Required properties:
-- compatible:		"aspeed,ast2500-gfx", "syscon"
-- reg:			contains offset/length value of the GFX memory
-			region.
-
-Example:
-
-gfx: display@1e6e6000 {
-	compatible = "aspeed,ast2500-gfx", "syscon";
-	reg = <0x1e6e6000 0x1000>;
-};

MAINTAINERS

···
 L:	[e-mail] (moderated for non-subscribers)
 S:	Supported
 T:	git https://gitlab.freedesktop.org/drm/misc/kernel.git
-F:	Documentation/devicetree/bindings/gpu/aspeed-gfx.txt
+F:	Documentation/devicetree/bindings/gpu/aspeed,ast2400-gfx.yaml
 F:	drivers/gpu/drm/aspeed/
 
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