[PATCH 1/3] ASoC: dt-bindings: renesas,r9a09g047-sound: Document audio_clkout clock-frequency

r9a09g047e57-smarc.dts set clock-frequency for the audio_clkout output,
but the binding never declared it, so dtbs_check fails:

  sound@13c00000 (renesas,r9a09g047-sound): Unevaluated properties
  are not allowed ('clock-frequency' was unexpected)

clock-cells is fixed to 0, so only a single audio_clkout applies.

Fixes: a86fd3c20218 ("ASoC: dt-bindings: sound: Add DT binding for RZ/G3E sound")
Signed-off-by: Tommaso Merciai <[email protected]>
---
 .../devicetree/bindings/sound/renesas,r9a09g047-sound.yaml     | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Documentation/devicetree/bindings/sound/renesas,r9a09g047-sound.yaml b/Documentation/devicetree/bindings/sound/renesas,r9a09g047-sound.yaml
index d7fa16554698..6e2b2c93b4b7 100644
--- a/Documentation/devicetree/bindings/sound/renesas,r9a09g047-sound.yaml
+++ b/Documentation/devicetree/bindings/sound/renesas,r9a09g047-sound.yaml
@@ -42,6 +42,9 @@ properties:
   "#clock-cells":
     const: 0
 
+  clock-frequency:
+    description: for audio_clkout
+
   "#address-cells":
     const: 1
 
-- 
2.54.0