dt-bindings: dma: Convert stm32 DMAMUX bindings to json-schema

Convert the STM32 DMAMUX binding to DT schema format using json-schema
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/dma/st,stm32-dmamux.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/dma/st,stm32-dmamux.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: STMicroelectronics STM32 DMA MUX (DMA request router) bindings
+
+maintainers:
+  - Amelie Delaunay <amelie.delaunay@st.com>
+
+allOf:
+  - $ref: "dma-router.yaml#"
+
+properties:
+  "#dma-cells":
+    const: 3
+
+  compatible:
+    const: st,stm32h7-dmamux
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  resets:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - dma-masters
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/clock/stm32mp1-clks.h>
+    #include <dt-bindings/reset/stm32mp1-resets.h>
+    dma-router@40020800 {
+      compatible = "st,stm32h7-dmamux";
+      reg = <0x40020800 0x3c>;
+      #dma-cells = <3>;
+      dma-requests = <128>;
+      dma-channels = <16>;
+      dma-masters = <&dma1 &dma2>;
+      clocks = <&timer_clk>;
+    };
+
+...
+

Documentation/devicetree/bindings/dma/stm32-dmamux.txt

-STM32 DMA MUX (DMA request router)
-
-Required properties:
-- compatible:	"st,stm32h7-dmamux"
-- reg:		Memory map for accessing module
-- #dma-cells:	Should be set to <3>.
-		First parameter is request line number.
-		Second is DMA channel configuration
-		Third is Fifo threshold
-		For more details about the three cells, please see
-		stm32-dma.txt documentation binding file
-- dma-masters:	Phandle pointing to the DMA controllers.
-		Several controllers are allowed. Only "st,stm32-dma" DMA
-		compatible are supported.
-
-Optional properties:
-- dma-channels : Number of DMA requests supported.
-- dma-requests : Number of DMAMUX requests supported.
-- resets: Reference to a reset controller asserting the DMA controller
-- clocks: Input clock of the DMAMUX instance.
-
-Example:
-
-/* DMA controller 1 */
-dma1: dma-controller@40020000 {
-	compatible = "st,stm32-dma";
-	reg = <0x40020000 0x400>;
-	interrupts = <11>,
-		     <12>,
-		     <13>,
-		     <14>,
-		     <15>,
-		     <16>,
-		     <17>,
-		     <47>;
-	clocks = <&timer_clk>;
-	#dma-cells = <4>;
-	st,mem2mem;
-	resets = <&rcc 150>;
-	dma-channels = <8>;
-	dma-requests = <8>;
-};
-
-/* DMA controller 1 */
-dma2: dma@40020400 {
-	compatible = "st,stm32-dma";
-	reg = <0x40020400 0x400>;
-	interrupts = <56>,
-		     <57>,
-		     <58>,
-		     <59>,
-		     <60>,
-		     <68>,
-		     <69>,
-		     <70>;
-	clocks = <&timer_clk>;
-	#dma-cells = <4>;
-	st,mem2mem;
-	resets = <&rcc 150>;
-	dma-channels = <8>;
-	dma-requests = <8>;
-};
-
-/* DMA mux */
-dmamux1: dma-router@40020800 {
-	compatible = "st,stm32h7-dmamux";
-	reg = <0x40020800 0x3c>;
-	#dma-cells = <3>;
-	dma-requests = <128>;
-	dma-channels = <16>;
-	dma-masters = <&dma1 &dma2>;
-	clocks = <&timer_clk>;
-};
-
-/* DMA client */
-usart1: serial@40011000 {
-	compatible = "st,stm32-usart", "st,stm32-uart";
-	reg = <0x40011000 0x400>;
-	interrupts = <37>;
-	clocks = <&timer_clk>;
-	dmas = <&dmamux1 41 0x414 0>,
-	       <&dmamux1 42 0x414 0>;
-	dma-names = "rx", "tx";
-};