drm/bridge: anx7625: Fill in empty ELD when no connector

Speaker may share I2S with DP and .get_eld callback will be called when
speaker is playing. When HDMI wans't connected, the connector will be
null. Instead of return an error, fill in empty ELD.

Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Reviewed-by: Xin Ji <xji@analogixsemi.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220414090003.1806535-1-hsinyi@chromium.org

drivers/gpu/drm/bridge/analogix/anx7625.c

@@ -1932,14 +1932,14 @@ static int anx7625_audio_get_eld(struct device *dev, void *data,
 	struct anx7625_data *ctx = dev_get_drvdata(dev);
 
 	if (!ctx->connector) {
-		dev_err(dev, "connector not initial\n");
-		return -EINVAL;
+		/* Pass en empty ELD if connector not available */
+		memset(buf, 0, len);
+	} else {
+		dev_dbg(dev, "audio copy eld\n");
+		memcpy(buf, ctx->connector->eld,
+		       min(sizeof(ctx->connector->eld), len));
 	}
 
-	dev_dbg(dev, "audio copy eld\n");
-	memcpy(buf, ctx->connector->eld,
-	       min(sizeof(ctx->connector->eld), len));
-
 	return 0;
 }