diff --git a/dix/input_priv.h b/dix/input_priv.h
index 69802e077..a03db8dc4 100644
--- a/dix/input_priv.h
+++ b/dix/input_priv.h
@@ -361,4 +361,13 @@ int InputThreadRegisterDev(int fd,
 
 int InputThreadUnregisterDev(int fd);
 
+/*
+ * @brief count the bits set in the given bitmask
+ *
+ * @param mask pointer to bitmask
+ * @param len size of bitmask in bits (may span multiple bytes)
+ * @return number of bits set in the given bitmask
+ */
+int CountBits(const uint8_t * mask, int len);
+
 #endif /* _XSERVER_INPUT_PRIV_H */
diff --git a/include/inputstr.h b/include/inputstr.h
index 3652b0d32..4508ffb96 100644
--- a/include/inputstr.h
+++ b/include/inputstr.h
@@ -63,7 +63,6 @@ extern _X_EXPORT void AssignTypeAndName(DeviceIntPtr dev,
 #define BitIsOn(ptr, bit) (!!(((const BYTE *) (ptr))[(bit)>>3] & (1 << ((bit) & 7))))
 #define SetBit(ptr, bit)  (((BYTE *) (ptr))[(bit)>>3] |= (1 << ((bit) & 7)))
 #define ClearBit(ptr, bit) (((BYTE *)(ptr))[(bit)>>3] &= ~(1 << ((bit) & 7)))
-extern _X_EXPORT int CountBits(const uint8_t * mask, int len);
 
 #define EMASKSIZE	(MAXDEVICES + 2)