[PATCH RESEND v3 2/9] dt-bindings: display: add verisilicon,dc

[Icenowy Zheng]

From: Icenowy Zheng <uwu at icenowy.me>

Verisilicon has a series of display controllers prefixed with DC and
with self-identification facility like their GC series GPUs.

Add a device tree binding for it.

Depends on the specific DC model, it can have either one or two display
outputs, and each display output could be set to DPI signal or "DP"
signal (which seems to be some plain parallel bus to HDMI controllers).

Signed-off-by: Icenowy Zheng <uwu at icenowy.me>
Signed-off-by: Icenowy Zheng <zhengxingda at iscas.ac.cn>
---
Changes in v3:
- Added SoC-specific compatible string, and arm the binding with clock /
  port checking for the specific SoC (with a 2-output DC).

Changes in v2:
- Fixed misspelt "versilicon" in title.
- Moved minItems in clock properties to be earlier than items.
- Re-aligned multi-line clocks and resets in example.

 .../bindings/display/verisilicon,dc.yaml      | 146 ++++++++++++++++++
 1 file changed, 146 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/verisilicon,dc.yaml

diff --git a/Documentation/devicetree/bindings/display/verisilicon,dc.yaml b/Documentation/devicetree/bindings/display/verisilicon,dc.yaml
new file mode 100644
index 0000000000000..522a544498bea
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/verisilicon,dc.yaml
@@ -0,0 +1,146 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/verisilicon,dc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Verisilicon DC-series display controllers
+
+maintainers:
+  - Icenowy Zheng <uwu at icenowy.me>
+
+properties:
+  $nodename:
+    pattern: "^display@[0-9a-f]+$"
+
+  compatible:
+    items:
+      - enum:
+          - thead,th1520-dc8200
+      - const: verisilicon,dc
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    minItems: 4
+    items:
+      - description: DC Core clock
+      - description: DMA AXI bus clock
+      - description: Configuration AHB bus clock
+      - description: Pixel clock of output 0
+      - description: Pixel clock of output 1
+
+  clock-names:
+    minItems: 4
+    items:
+      - const: core
+      - const: axi
+      - const: ahb
+      - const: pix0
+      - const: pix1
+
+  resets:
+    items:
+      - description: DC Core reset
+      - description: DMA AXI bus reset
+      - description: Configuration AHB bus reset
+
+  reset-names:
+    items:
+      - const: core
+      - const: axi
+      - const: ahb
+
+  ports:
+    $ref: /schemas/graph.yaml#/properties/ports
+
+    properties:
+      port at 0:
+        $ref: /schemas/graph.yaml#/properties/port
+        description: The first output channel , endpoint 0 should be
+          used for DPI format output and endpoint 1 should be used
+          for DP format output.
+
+      port at 1:
+        $ref: /schemas/graph.yaml#/properties/port
+        description: The second output channel if the DC variant
+          supports. Follow the same endpoint addressing rule with
+          the first port.
+
+    required:
+      - port at 0
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - clock-names
+  - ports
+
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: thead,th1520-dc8200
+    then:
+      properties:
+        clocks:
+          minItems: 5
+        ports:
+          required:
+            - port at 0
+            - port at 1
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    #include <dt-bindings/clock/thead,th1520-clk-ap.h>
+    #include <dt-bindings/reset/thead,th1520-reset.h>
+    soc {
+      #address-cells = <2>;
+      #size-cells = <2>;
+
+      display at ffef600000 {
+        compatible = "thead,th1520-dc8200", "verisilicon,dc";
+        reg = <0xff 0xef600000 0x0 0x100000>;
+        interrupts = <93 IRQ_TYPE_LEVEL_HIGH>;
+        clocks = <&clk_vo CLK_DPU_CCLK>,
+                 <&clk_vo CLK_DPU_ACLK>,
+                 <&clk_vo CLK_DPU_HCLK>,
+                 <&clk_vo CLK_DPU_PIXELCLK0>,
+                 <&clk_vo CLK_DPU_PIXELCLK1>;
+        clock-names = "core", "axi", "ahb", "pix0", "pix1";
+        resets = <&rst TH1520_RESET_ID_DPU_CORE>,
+                 <&rst TH1520_RESET_ID_DPU_AXI>,
+                 <&rst TH1520_RESET_ID_DPU_AHB>;
+        reset-names = "core", "axi", "ahb";
+
+        ports {
+          #address-cells = <1>;
+          #size-cells = <0>;
+
+          port at 0 {
+            reg = <0>;
+          };
+
+          port at 1 {
+            reg = <1>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            dpu_out_dp1: endpoint at 1 {
+              reg = <1>;
+              remote-endpoint = <&hdmi_in>;
+            };
+          };
+        };
+      };
+    };
-- 
2.52.0