[PATCH v2] dt-bindings: timer: renesas,tmu: Document input capture interrupt

Some Timer Unit (TMU) instances with 3 channels support a fourth
interrupt: an input capture interrupt for the third channel.

While at it, document the meaning of the four interrupts, and add
"interrupt-names" for clarity.

Update the example to match reality.

Inspired by a patch by Yoshinori Sato for SH.

Signed-off-by: Geert Uytterhoeven <[email protected]>
---
v2:
  - Reword interrupt descriptions.

The corresponding DTS updates can be found in series "[PATCH 0/2]
ARM/arm64: dts: renesas: Improve TMU interrupt descriptions".
https://lore.kernel.org/r/[email protected]
Once the DTS updates are upstream, "interrupt-names" can be made
required.
---
 .../devicetree/bindings/timer/renesas,tmu.yaml | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/timer/renesas,tmu.yaml b/Documentation/devicetree/bindings/timer/renesas,tmu.yaml
index a67e427a9e7e22aa..84bbe15028a1de94 100644
--- a/Documentation/devicetree/bindings/timer/renesas,tmu.yaml
+++ b/Documentation/devicetree/bindings/timer/renesas,tmu.yaml
@@ -46,7 +46,19 @@ properties:
 
   interrupts:
     minItems: 2
-    maxItems: 3
+    items:
+      - description: Underflow interrupt, channel 0
+      - description: Underflow interrupt, channel 1
+      - description: Underflow interrupt, channel 2
+      - description: Input capture interrupt, channel 2
+
+  interrupt-names:
+    minItems: 2
+    items:
+      - const: tuni0
+      - const: tuni1
+      - const: tuni2
+      - const: ticpi2
 
   clocks:
     maxItems: 1
@@ -100,7 +112,9 @@ examples:
             reg = <0xffd80000 0x30>;
             interrupts = <GIC_SPI 32 IRQ_TYPE_LEVEL_HIGH>,
                          <GIC_SPI 33 IRQ_TYPE_LEVEL_HIGH>,
-                         <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>;
+                         <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>,
+                         <GIC_SPI 35 IRQ_TYPE_LEVEL_HIGH>;
+            interrupt-names = "tuni0", "tuni1", "tuni2", "ticpi2";
             clocks = <&mstp0_clks R8A7779_CLK_TMU0>;
             clock-names = "fck";
             power-domains = <&sysc R8A7779_PD_ALWAYS_ON>;
-- 
2.34.1