ASoC: mxs-saif: Store saif state

Trigger commands may be passed multiple times. To avoid errors with
clk_enable/disable, store the saif state and return if saif is already
running/stopped.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/sound/soc/mxs/mxs-saif.h b/sound/soc/mxs/mxs-saif.h
index 53eaa4b..fbaf7ba 100644
--- a/sound/soc/mxs/mxs-saif.h
+++ b/sound/soc/mxs/mxs-saif.h
@@ -124,6 +124,11 @@
 
 	u32 fifo_underrun;
 	u32 fifo_overrun;
+
+	enum {
+		MXS_SAIF_STATE_STOPPED,
+		MXS_SAIF_STATE_RUNNING,
+	} state;
 };
 
 extern int mxs_saif_put_mclk(unsigned int saif_id);