dt-bindings: dma: Document RZ/G2L bindings

Document RZ/G2L DMAC bindings.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210806095322.2326-2-biju.das.jz@bp.renesas.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Documentation/devicetree/bindings/dma/renesas,rz-dmac.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/dma/renesas,rz-dmac.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Renesas RZ/G2L DMA Controller
+
+maintainers:
+  - Biju Das <biju.das.jz@bp.renesas.com>
+
+allOf:
+  - $ref: "dma-controller.yaml#"
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - renesas,r9a07g044-dmac # RZ/G2{L,LC}
+      - const: renesas,rz-dmac
+
+  reg:
+    items:
+      - description: Control and channel register block
+      - description: DMA extended resource selector block
+
+  interrupts:
+    maxItems: 17
+
+  interrupt-names:
+    items:
+      - const: error
+      - const: ch0
+      - const: ch1
+      - const: ch2
+      - const: ch3
+      - const: ch4
+      - const: ch5
+      - const: ch6
+      - const: ch7
+      - const: ch8
+      - const: ch9
+      - const: ch10
+      - const: ch11
+      - const: ch12
+      - const: ch13
+      - const: ch14
+      - const: ch15
+
+  clocks:
+    items:
+      - description: DMA main clock
+      - description: DMA register access clock
+
+  '#dma-cells':
+    const: 1
+    description:
+      The cell specifies the encoded MID/RID values of the DMAC port
+      connected to the DMA client and the slave channel configuration
+      parameters.
+      bits[0:9] - Specifies MID/RID value
+      bit[10] - Specifies DMA request high enable (HIEN)
+      bit[11] - Specifies DMA request detection type (LVL)
+      bits[12:14] - Specifies DMAACK output mode (AM)
+      bit[15] - Specifies Transfer Mode (TM)
+
+  dma-channels:
+    const: 16
+
+  power-domains:
+    maxItems: 1
+
+  resets:
+    items:
+      - description: Reset for DMA ARESETN reset terminal
+      - description: Reset for DMA RST_ASYNC reset terminal
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - interrupt-names
+  - clocks
+  - '#dma-cells'
+  - dma-channels
+  - power-domains
+  - resets
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/clock/r9a07g044-cpg.h>
+
+    dmac: dma-controller@11820000 {
+        compatible = "renesas,r9a07g044-dmac",
+                     "renesas,rz-dmac";
+        reg = <0x11820000 0x10000>,
+              <0x11830000 0x10000>;
+        interrupts = <GIC_SPI 141 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 125 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 126 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 127 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 128 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 129 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 130 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 131 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 132 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 133 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 134 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 135 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 136 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 137 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 138 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 139 IRQ_TYPE_EDGE_RISING>,
+                     <GIC_SPI 140 IRQ_TYPE_EDGE_RISING>;
+        interrupt-names = "error",
+                          "ch0", "ch1", "ch2", "ch3",
+                          "ch4", "ch5", "ch6", "ch7",
+                          "ch8", "ch9", "ch10", "ch11",
+                          "ch12", "ch13", "ch14", "ch15";
+        clocks = <&cpg CPG_MOD R9A07G044_DMAC_ACLK>,
+                 <&cpg CPG_MOD R9A07G044_DMAC_PCLK>;
+        power-domains = <&cpg>;
+        resets = <&cpg R9A07G044_DMAC_ARESETN>,
+                 <&cpg R9A07G044_DMAC_RST_ASYNC>;
+        #dma-cells = <1>;
+        dma-channels = <16>;
+    };