[PATCH v3 01/10] ASoC: dt-bindings: renesas,fsi: add support multiple clocks

[phucduc.bui@gmail.com]

From: bui duc phuc <phucduc.bui@gmail.com>

The FSI on r8a7740 requires the SPU bus/bridge clock to be enabled before
accessing its registers. Without this clock, any register access leads to
a system hang as the FSI block sits behind the SPU bus.
Update the binding to support multiple clocks to properly describe the
hardware clock tree, including:
  - SPU bus/bridge clock (spu) for register access.
  - CPG DIV6 clocks (icka/b) as functional clock parents.
  - FSI internal dividers (diva/b) for audio clock generation.
  - External clock inputs (xcka/b) provided by the board.

Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
---
 .../bindings/sound/renesas,fsi.yaml           | 27 ++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/sound/renesas,fsi.yaml b/Documentation/devicetree/bindings/sound/renesas,fsi.yaml
index df91991699a7..c50e7115b21a 100644
--- a/Documentation/devicetree/bindings/sound/renesas,fsi.yaml
+++ b/Documentation/devicetree/bindings/sound/renesas,fsi.yaml
@@ -38,7 +38,32 @@ properties:
     maxItems: 1
 
   clocks:
-    maxItems: 1
+    minItems: 1
+    items:
+      - description: Main FSI module clock
+      - description: |
+          SPU bus/bridge clock. On R8A7740, this clock must be enabled to allow
+          register access as the FSI block is connected behind the SPU bus.
+      - description: CPG DIV6 functional clocks for FSI port A
+      - description: CPG DIV6 functional clocks for FSI port B
+      - description: Internal FSI dividers for port A used for audio clock generation
+      - description: Internal FSI dividers for port B used for audio clock generation
+      - description: External clock inputs for FSI port A provided by the board
+      - description: External clock inputs for FSI port B provided by the board
+
+  clock-names:
+    minItems: 1
+    maxItems: 8
+    items:
+      enum:
+        - fck  # Main FSI module clock
+        - spu  # optional SPU bus/bridge clock
+        - icka # optional CPG DIV6 functional clocks for FSI port A
+        - ickb # optional CPG DIV6 functional clocks for FSI port B
+        - diva # optional Internal FSI dividers for port A used for audio clock generation
+        - divb # optional Internal FSI dividers for port B used for audio clock generation
+        - xcka # optional External clock inputs for FSI port A provided by the board
+        - xckb # optional External clock inputs for FSI port B provided by the board
 
   power-domains:
     maxItems: 1
-- 
2.43.0