diff --git a/sound/pci/ctxfi/cthw20k1.c b/sound/pci/ctxfi/cthw20k1.c
index 53572d92ef5d8..44283bd7b2df3 100644
--- a/sound/pci/ctxfi/cthw20k1.c
+++ b/sound/pci/ctxfi/cthw20k1.c
@@ -25,6 +25,7 @@
 #include <linux/spinlock.h>
 #include <linux/kernel.h>
 #include <linux/interrupt.h>
+#include <linux/delay.h>
 
 #define CT_XFI_DMA_MASK		DMA_BIT_MASK(32) /* 32 bits */
 
diff --git a/sound/pci/ctxfi/cthw20k2.c b/sound/pci/ctxfi/cthw20k2.c
index cdcb75cc33b68..9c2d38b4faa12 100644
--- a/sound/pci/ctxfi/cthw20k2.c
+++ b/sound/pci/ctxfi/cthw20k2.c
@@ -24,6 +24,7 @@
 #include <linux/string.h>
 #include <linux/kernel.h>
 #include <linux/interrupt.h>
+#include <linux/delay.h>
 
 #define CT_XFI_DMA_MASK		DMA_BIT_MASK(32) /* 32 bits */