dt-bindings: net: can: add support for Allwinner R40 CAN controller

Allwinner R40 (also known as A40i, T3, V40) has a CAN controller. The
controller is the same as in earlier A10 and A20 SoCs, but needs reset
line to be deasserted before use.

This patch Introduces new compatible for R40 CAN controller with
required resets property.

Link: https://lore.kernel.org/all/20211122104616.537156-2-boger@wirenboard.com
Signed-off-by: Evgeny Boger <boger@wirenboard.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Documentation/devicetree/bindings/net/can/allwinner,sun4i-a10-can.yaml

@@ -17,6 +17,7 @@ properties:
           - const: allwinner,sun7i-a20-can
           - const: allwinner,sun4i-a10-can
       - const: allwinner,sun4i-a10-can
+      - const: allwinner,sun8i-r40-can
 
   reg:
     maxItems: 1
@@ -27,6 +28,19 @@ properties:
   clocks:
     maxItems: 1
 
+  resets:
+    maxItems: 1
+
+if:
+  properties:
+    compatible:
+      contains:
+        const: allwinner,sun8i-r40-can
+
+then:
+  required:
+    - resets
+
 required:
   - compatible
   - reg
@@ -47,5 +61,15 @@ examples:
         interrupts = <GIC_SPI 26 IRQ_TYPE_LEVEL_HIGH>;
         clocks = <&ccu CLK_APB1_CAN>;
     };
+  - |
+    #define RST_BUS_CAN		68
+    #define CLK_BUS_CAN		91
+    can1: can@1c2bc00 {
+        compatible = "allwinner,sun8i-r40-can";
+        reg = <0x01c2bc00 0x400>;
+        interrupts = <GIC_SPI 26 IRQ_TYPE_LEVEL_HIGH>;
+        clocks = <&ccu CLK_BUS_CAN>;
+        resets = <&ccu RST_BUS_CAN>;
+    };
 
 ...