[PATCH v12 1/7] dt-bindings: serial: Added secondary clock for RZ/T2H RSCI

[Prabhakar]

From: Thierry Bultel <thierry.bultel.yh at bp.renesas.com>

At boot, the default clock is the PCLKM core clock (synchronous
clock, which is enabled by the bootloader).
For different baudrates, the asynchronous clock input must be used.
Clock selection is made by an internal register of RCSI.

Add the optional "sck", external clock input.

Also remove the unneeded serial0 alias from the dts example.

Signed-off-by: Thierry Bultel <thierry.bultel.yh at bp.renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj at bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas at glider.be>
---
Hi Rob,
As mentioned in the thread [1] below there are no users of the RSCI binding
hence this change doesn not break any ABI.

[1] https://lore.kernel.org/all/CAMuHMdUThuWxxznhjvcn5cOFCWOkb5u-fRYwTOoenDRY=4H6FA@mail.gmail.com/

Cheers, Prabhakar
---
 .../bindings/serial/renesas,rsci.yaml           | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/Documentation/devicetree/bindings/serial/renesas,rsci.yaml b/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
index ea879db5f485..1bf255407df0 100644
--- a/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
+++ b/Documentation/devicetree/bindings/serial/renesas,rsci.yaml
@@ -35,10 +35,15 @@ 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
@@ -60,10 +65,6 @@ examples:
     #include <dt-bindings/interrupt-controller/arm-gic.h>
     #include <dt-bindings/clock/renesas-cpg-mssr.h>
 
-    aliases {
-        serial0 = &sci0;
-    };
-
     sci0: serial at 80005000 {
         compatible = "renesas,r9a09g077-rsci";
         reg = <0x80005000 0x400>;
@@ -72,7 +73,7 @@ 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>;
     };
-- 
2.49.0