ASoC: rsnd: add warning message to rsnd_kctrl_accept_runtime()

Add warning message to rsnd_kctrl_accept_runtime(), when kctrl
update is rejected due to corresponding dai-link is idle.
So that user can notice the reason of kctrl update failure.

Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
Signed-off-by: Timo Wischer <twischer@de.adit-jv.com>
[kuninori: adjust to upstream]
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/sh/rcar/core.c b/sound/soc/sh/rcar/core.c
index f8425d8..ab7e317 100644
--- a/sound/soc/sh/rcar/core.c
+++ b/sound/soc/sh/rcar/core.c
@@ -1263,8 +1263,15 @@
 int rsnd_kctrl_accept_runtime(struct rsnd_dai_stream *io)
 {
 	struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
+	struct rsnd_priv *priv = rsnd_io_to_priv(io);
+	struct device *dev = rsnd_priv_to_dev(priv);
 
-	return !!runtime;
+	if (!runtime) {
+		dev_warn(dev, "Can't update kctrl when idle\n");
+		return 0;
+	}
+
+	return 1;
 }
 
 struct rsnd_kctrl_cfg *rsnd_kctrl_init_m(struct rsnd_kctrl_cfg_m *cfg)