dt-bindings: timer: Convert csky,mptimer to DT schema

Convert the C-SKY Multi-processor timer binding to DT schema format.
It's a straight-forward conversion.

Signed-off-by: Rob Herring (Arm) <[e-mail]>
Acked-by: Guo Ren <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Daniel Lezcano <[e-mail]>

Documentation/devicetree/bindings/timer/csky,mptimer.txt

···
-============================
-C-SKY Multi-processors Timer
-============================
-
-C-SKY multi-processors timer is designed for C-SKY SMP system and the
-regs is accessed by cpu co-processor 4 registers with mtcr/mfcr.
-
- - PTIM_CTLR "cr<0, 14>" Control reg to start reset timer.
- - PTIM_TSR  "cr<1, 14>" Interrupt cleanup status reg.
- - PTIM_CCVR "cr<3, 14>" Current counter value reg.
- - PTIM_LVR  "cr<6, 14>" Window value reg to trigger next event.
-
-==============================
-timer node bindings definition
-==============================
-
-	Description: Describes SMP timer
-
-	PROPERTIES
-
-	- compatible
-		Usage: required
-		Value type: <string>
-		Definition: must be "csky,mptimer"
-	- clocks
-		Usage: required
-		Value type: <node>
-		Definition: must be input clk node
-	- interrupts
-		Usage: required
-		Value type: <u32>
-		Definition: must be timer irq num defined by soc
-
-Examples:
----------
-
-	timer: timer {
-		compatible = "csky,mptimer";
-		clocks = <&dummy_apb_clk>;
-		interrupts = <16>;
-		interrupt-parent = <&intc>;
-	};

Documentation/devicetree/bindings/timer/csky,mptimer.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/timer/csky,mptimer.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: C-SKY Multi-processors Timer
+
+maintainers:
+  - Flavio Suligoi <[e-mail]>
+  - Guo Ren <[e-mail]>
+
+description: |
+  C-SKY multi-processors timer is designed for C-SKY SMP system and the regs are
+  accessed by cpu co-processor 4 registers with mtcr/mfcr.
+
+   - PTIM_CTLR "cr<0, 14>" Control reg to start reset timer.
+   - PTIM_TSR  "cr<1, 14>" Interrupt cleanup status reg.
+   - PTIM_CCVR "cr<3, 14>" Current counter value reg.
+   - PTIM_LVR  "cr<6, 14>" Window value reg to trigger next event.
+
+properties:
+  compatible:
+    items:
+      - const: csky,mptimer
+
+  clocks:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+required:
+  - compatible
+  - clocks
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    timer {
+        compatible = "csky,mptimer";
+        clocks = <&dummy_apb_clk>;
+        interrupts = <16>;
+    };