diff --git a/sound/soc/mediatek/mt2701/mt2701-afe-pcm.c b/sound/soc/mediatek/mt2701/mt2701-afe-pcm.c
index 15522c08a967b8b3c14334a52704b921db788f8a..34a6123480d3e708e7b934c967ea7b5f85131336 100644
--- a/sound/soc/mediatek/mt2701/mt2701-afe-pcm.c
+++ b/sound/soc/mediatek/mt2701/mt2701-afe-pcm.c
@@ -69,7 +69,7 @@ static const struct mt2701_afe_rate mt2701_afe_i2s_rates[] = {
 	{ .rate = 352800, .regvalue = 24 },
 };
 
-int mt2701_dai_num_to_i2s(struct mtk_base_afe *afe, int num)
+static int mt2701_dai_num_to_i2s(struct mtk_base_afe *afe, int num)
 {
 	int val = num - MT2701_IO_I2S;