diff --git a/sound/soc/dwc/designware_i2s.c b/sound/soc/dwc/designware_i2s.c
index 1bd042b..1aa5130 100644
--- a/sound/soc/dwc/designware_i2s.c
+++ b/sound/soc/dwc/designware_i2s.c
@@ -107,7 +107,8 @@
 	}
 }
 
-void i2s_start(struct dw_i2s_dev *dev, struct snd_pcm_substream *substream)
+static void i2s_start(struct dw_i2s_dev *dev,
+		      struct snd_pcm_substream *substream)
 {
 
 	i2s_write_reg(dev->i2s_base, IER, 1);