diff --git a/Documentation/devicetree/bindings/serial/renesas,rsci.yaml b/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
index 4aacc44bb509..f20de85d5304 100644
--- a/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
+++ b/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
@@ -41,10 +41,15 @@ properties:
       - const: tei
 
   clocks:
-    maxItems: 1
+    minItems: 2
+    maxItems: 3
 
   clock-names:
-    const: fck # UART functional clock
+    minItems: 2
+    items:
+      - const: operation
+      - const: bus
+      - const: sck # optional external clock input
 
   power-domains:
     maxItems: 1
@@ -66,10 +71,6 @@ examples:
     #include <dt-bindings/interrupt-controller/arm-gic.h>
     #include <dt-bindings/clock/renesas-cpg-mssr.h>
 
-    aliases {
-        serial0 = &sci0;
-    };
-
     sci0: serial@80005000 {
         compatible = "renesas,r9a09g077-rsci";
         reg = <0x80005000 0x400>;
@@ -78,7 +79,7 @@ examples:
                      <GIC_SPI 592 IRQ_TYPE_EDGE_RISING>,
                      <GIC_SPI 593 IRQ_TYPE_LEVEL_HIGH>;
         interrupt-names = "eri", "rxi", "txi", "tei";
-        clocks = <&cpg CPG_MOD 108>;
-        clock-names = "fck";
+        clocks = <&cpg CPG_MOD 8>, <&cpg CPG_CORE 13>;
+        clock-names = "operation", "bus";
         power-domains = <&cpg>;
     };