Add a string property to assign ASoC platform driver name. It also
represents the rpmsg channel this sound card sits on. This property
can be omitted if there is only one sound card and it sits on
"rpmsg-audio-channel".

Signed-off-by: Chancel Liu <redacted>
---
 .../devicetree/bindings/sound/fsl,rpmsg.yaml  | 34 +++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml b/Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml
index d370c98a62c7..35e3cb9f768b 100644
--- a/Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml
+++ b/Documentation/devicetree/bindings/sound/fsl,rpmsg.yaml

@@ -11,8 +11,11 @@ maintainers:
 
 description: |
   fsl_rpmsg is a virtual audio device. Mapping to real hardware devices
-  are SAI, DMA controlled by Cortex M core. What we see from Linux
-  side is a device which provides audio service by rpmsg channel.
+  are SAI, MICFIL, DMA controlled by Cortex M core. What we see from
+  Linux side is a device which provides audio service by rpmsg channel.
+  We can create different sound cards which access different hardwares
+  such as SAI, MICFIL, .etc through building rpmsg channels between
+  Cortex-A and Cortex-M.
 
 properties:
   compatible:

@@ -85,6 +88,14 @@ properties:
       This is a boolean property. If present, the receiving function
       will be enabled.
 
+  fsl,platform:
+    $ref: /schemas/types.yaml#/definitions/string
+    description: |
+      A string property to assign ASoC platform driver name. 

It also
+      represents the rpmsg channel this sound card sits on. This property
+      can be omitted if there is only one sound card and it sits on
+      "rpmsg-audio-channel".
+
 required:
   - compatible
   - model

@@ -107,3 +118,22 @@ examples:
                  <&clk IMX8MN_AUDIO_PLL2_OUT>;
         clock-names = "ipg", "mclk", "dma", "pll8k", "pll11k";
     };
+
+  - |
+    #include <dt-bindings/clock/imx8mm-clock.h>
+
+    rpmsg_micfil: rpmsg_micfil {