ASoC: rsnd: add rsnd_set_slot() / rsnd_get_slot_num()

TDM will use 6 or 8 slots on 1 SSI, and Multi channel will use
6 or 8 slots on few SSI (each SSI uses 2 slots).
Thus, this adds new slot control functions which can be prepare
for Multi channel support.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/sh/rcar/rsnd.h b/sound/soc/sh/rcar/rsnd.h
index 804f2f5..c9aef23 100644
--- a/sound/soc/sh/rcar/rsnd.h
+++ b/sound/soc/sh/rcar/rsnd.h
@@ -293,8 +293,11 @@
 			void (*callback)(struct rsnd_mod *mod,
 					 struct rsnd_dai_stream *io));
 
+void rsnd_set_slot(struct rsnd_dai *rdai,
+		   int slots, int slots_total);
 int rsnd_get_slot(struct rsnd_dai_stream *io);
 int rsnd_get_slot_width(struct rsnd_dai_stream *io);
+int rsnd_get_slot_num(struct rsnd_dai_stream *io);
 
 /*
  *	R-Car sound DAI
@@ -334,6 +337,7 @@
 	struct rsnd_priv *priv;
 
 	int slots;
+	int slots_num;
 
 	unsigned int clk_master:1;
 	unsigned int bit_clk_inv:1;