diff --git a/drivers/mfd/ucb1x00-core.c b/drivers/mfd/ucb1x00-core.c
index 252b74188ec2..b281217334eb 100644
--- a/drivers/mfd/ucb1x00-core.c
+++ b/drivers/mfd/ucb1x00-core.c
@@ -27,6 +27,7 @@
 #include <linux/mutex.h>
 #include <linux/mfd/ucb1x00.h>
 #include <linux/gpio.h>
+#include <linux/semaphore.h>
 
 #include <mach/dma.h>
 #include <mach/hardware.h>
diff --git a/include/linux/mfd/ucb1x00.h b/include/linux/mfd/ucb1x00.h
index aa9c3789bed4..4321f044d1e4 100644
--- a/include/linux/mfd/ucb1x00.h
+++ b/include/linux/mfd/ucb1x00.h
@@ -12,6 +12,7 @@
 
 #include <linux/mfd/mcp.h>
 #include <linux/gpio.h>
+#include <linux/semaphore.h>
 
 #define UCB_IO_DATA	0x00
 #define UCB_IO_DIR	0x01