ASoC: imx-card: support playback or capture only

Merge series from Shengjiu Wang <shengjiu.wang@nxp.com>:

Be similar to audio graph card, support playback or capture only for
imx-audio-card.

imx-card can't directly refer to audio-graph-port.yaml, because it is
not based on 'ports'. Add playback-only and capture-only property
directly

Documentation/devicetree/bindings/sound/imx-audio-card.yaml

@@ -46,6 +46,14 @@ patternProperties:
         description: see tdm-slot.txt.
         $ref: /schemas/types.yaml#/definitions/uint32
 
+      playback-only:
+        description: link is used only for playback
+        $ref: /schemas/types.yaml#/definitions/flag
+
+      capture-only:
+        description: link is used only for capture
+        $ref: /schemas/types.yaml#/definitions/flag
+
       cpu:
         description: Holds subnode which indicates cpu dai.
         type: object
@@ -71,6 +79,12 @@ patternProperties:
       - link-name
       - cpu
 
+    allOf:
+      - not:
+          required:
+            - playback-only
+            - capture-only
+
     additionalProperties: false
 
 required:

sound/soc/fsl/imx-card.c

@@ -518,6 +518,7 @@ static int imx_card_parse_of(struct imx_card_data *data)
 	struct snd_soc_dai_link *link;
 	struct dai_link_data *link_data;
 	struct of_phandle_args args;
+	bool playback_only, capture_only;
 	int ret, num_links;
 	u32 asrc_fmt = 0;
 	u32 width;
@@ -679,6 +680,10 @@ static int imx_card_parse_of(struct imx_card_data *data)
 			link->ops = &imx_aif_ops;
 		}
 
+		graph_util_parse_link_direction(np, &playback_only, &capture_only);
+		link->playback_only = playback_only;
+		link->capture_only = capture_only;
+
 		/* Get dai fmt */
 		ret = simple_util_parse_daifmt(dev, np, codec,
 					       NULL, &link->dai_fmt);