diff --git a/include/linux/bcd.h b/include/linux/bcd.h
index c545308125b0..7ac518e3c152 100644
--- a/include/linux/bcd.h
+++ b/include/linux/bcd.h
@@ -10,8 +10,13 @@
 #ifndef _BCD_H
 #define _BCD_H
 
-#define BCD2BIN(val)	(((val) & 0x0f) + ((val)>>4)*10)
-#define BIN2BCD(val)	((((val)/10)<<4) + (val)%10)
+#include <linux/compiler.h>
+
+unsigned bcd2bin(unsigned char val) __attribute_const__;
+unsigned char bin2bcd(unsigned val) __attribute_const__;
+
+#define BCD2BIN(val)	bcd2bin(val)
+#define BIN2BCD(val)	bin2bcd(val)
 
 /* backwards compat */
 #define BCD_TO_BIN(val) ((val)=BCD2BIN(val))
diff --git a/lib/Makefile b/lib/Makefile
index 818c4d455518..9085ad6fa53d 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -18,7 +18,7 @@ lib-$(CONFIG_SMP) += cpumask.o
 
 lib-y	+= kobject.o kref.o klist.o
 
-obj-y += div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
+obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
 	 bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o
 
 ifeq ($(CONFIG_DEBUG_KOBJECT),y)
diff --git a/lib/bcd.c b/lib/bcd.c
new file mode 100644
index 000000000000..d74257fd0fe7
--- /dev/null
+++ b/lib/bcd.c
@@ -0,0 +1,14 @@
+#include <linux/bcd.h>
+#include <linux/module.h>
+
+unsigned bcd2bin(unsigned char val)
+{
+	return (val & 0x0f) + (val >> 4) * 10;
+}
+EXPORT_SYMBOL(bcd2bin);
+
+unsigned char bin2bcd(unsigned val)
+{
+	return ((val / 10) << 4) + val % 10;
+}
+EXPORT_SYMBOL(bin2bcd);