[PATCH v3 2/4] ASoC: dt-bindings: fsl,sai: Add AUDMIX mode support on i.MX952

[Shengjiu Wang <shengjiu.wang@nxp.com>]

The SAI can connect to AUDMIX, but AUDMIX can be bypassed or not on
i.MX952. There are three use cases:

1) SAI -> Codec (No AUDMIX between SAI and Codec)
2) SAI -> Codec (Has AUDMIX, but AUDMIX is bypassed)
3) SAI -> AUDMIX -> Codec (Has AUDMIX and used)

So add 'fsl,sai-amix-mode' property for this feature

fsl,sai-amix-mode = "none": is for case 1)
fsl,sai-amix-mode = "bypass": is for case 2)
fsl,sai-amix-mode = "audmix": is for case 3)

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
---
 .../devicetree/bindings/sound/fsl,sai.yaml       | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/Documentation/devicetree/bindings/sound/fsl,sai.yaml b/Documentation/devicetree/bindings/sound/fsl,sai.yaml
index d838ee0b61cb..83b5ea5f3d70 100644
--- a/Documentation/devicetree/bindings/sound/fsl,sai.yaml
+++ b/Documentation/devicetree/bindings/sound/fsl,sai.yaml
@@ -133,6 +133,13 @@ properties:
         - description: dataline mask for 'rx'
         - description: dataline mask for 'tx'
 
+  fsl,sai-amix-mode:
+    $ref: /schemas/types.yaml#/definitions/string
+    description:
+      The audmix module is bypassed from hardware or not.
+    enum: [none, bypass, audmix]
+    default: none
+
   fsl,sai-mclk-direction-output:
     description: SAI will output the SAI MCLK clock.
     type: boolean
@@ -180,6 +187,15 @@ allOf:
       properties:
         fsl,sai-synchronous-rx: false
 
+  - if:
+      required:
+        - fsl,sai-amix-mode
+    then:
+      properties:
+        compatible:
+          contains:
+            const: fsl,imx952-sai
+
 required:
   - compatible
   - reg
-- 
2.34.1