diff --git a/src/mainboard/kontron/986lcd-m/romstage.c b/src/mainboard/kontron/986lcd-m/romstage.c
index 549facd333..ba18720b3f 100644
--- a/src/mainboard/kontron/986lcd-m/romstage.c
+++ b/src/mainboard/kontron/986lcd-m/romstage.c
@@ -32,7 +32,7 @@
 #include "option_table.h"
 #include <console/console.h>
 #include <cpu/x86/bist.h>
-#include "superio/winbond/w83627thg/early_serial.c"
+#include <superio/winbond/w83627thg/w83627thg.h>
 #include "northbridge/intel/i945/i945.h"
 #include "northbridge/intel/i945/raminit.h"
 #include "southbridge/intel/i82801gx/i82801gx.h"
diff --git a/src/mainboard/lanner/em8510/romstage.c b/src/mainboard/lanner/em8510/romstage.c
index 9a7314d600..335f9ecbfc 100644
--- a/src/mainboard/lanner/em8510/romstage.c
+++ b/src/mainboard/lanner/em8510/romstage.c
@@ -34,7 +34,7 @@
 #include "southbridge/intel/i82801dx/i82801dx.h"
 #include "northbridge/intel/i855/raminit.h"
 #include "northbridge/intel/i855/debug.c"
-#include "superio/winbond/w83627thg/early_serial.c"
+#include <superio/winbond/w83627thg/w83627thg.h>
 #include "cpu/x86/bist.h"
 
 #define SERIAL_DEV PNP_DEV(0x2e, W83627THG_SP1)
diff --git a/src/mainboard/msi/ms7135/romstage.c b/src/mainboard/msi/ms7135/romstage.c
index ebe2526f5c..ccb420a259 100644
--- a/src/mainboard/msi/ms7135/romstage.c
+++ b/src/mainboard/msi/ms7135/romstage.c
@@ -31,7 +31,7 @@
 #include <pc80/mc146818rtc.h>
 #include "cpu/x86/lapic.h"
 #include "northbridge/amd/amdk8/reset_test.c"
-#include "superio/winbond/w83627thg/early_serial.c"
+#include <superio/winbond/w83627thg/w83627thg.h>
 #include <cpu/amd/model_fxx_rev.h>
 #include <console/console.h>
 #include "northbridge/amd/amdk8/incoherent_ht.c"
diff --git a/src/mainboard/winent/mb6047/romstage.c b/src/mainboard/winent/mb6047/romstage.c
index b180ef7a35..07f235c8a1 100644
--- a/src/mainboard/winent/mb6047/romstage.c
+++ b/src/mainboard/winent/mb6047/romstage.c
@@ -16,7 +16,7 @@
 #include "cpu/x86/lapic.h"
 #include "northbridge/amd/amdk8/reset_test.c"
 #include "northbridge/amd/amdk8/debug.c"
-#include "superio/winbond/w83627thg/early_serial.c"
+#include <superio/winbond/w83627thg/w83627thg.h>
 #include "cpu/x86/bist.h"
 #include "northbridge/amd/amdk8/setup_resource_map.c"
 
diff --git a/src/superio/winbond/w83627thg/Makefile.inc b/src/superio/winbond/w83627thg/Makefile.inc
index 8a03c8fa59..20a2ad0e60 100644
--- a/src/superio/winbond/w83627thg/Makefile.inc
+++ b/src/superio/winbond/w83627thg/Makefile.inc
@@ -20,5 +20,5 @@
 ## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 ##
 
+romstage-$(CONFIG_SUPERIO_WINBOND_W83627THG) += early_serial.c
 ramstage-$(CONFIG_SUPERIO_WINBOND_W83627THG) += superio.c
-
diff --git a/src/superio/winbond/w83627thg/chip.h b/src/superio/winbond/w83627thg/chip.h
index 692715e2c2..1677b97fec 100644
--- a/src/superio/winbond/w83627thg/chip.h
+++ b/src/superio/winbond/w83627thg/chip.h
@@ -30,4 +30,4 @@ struct superio_winbond_w83627thg_config {
 	struct pc_keyboard keyboard;
 };
 
-#endif
+#endif /* SUPERIO_WINBOND_W83627THG_CHIP_H */
diff --git a/src/superio/winbond/w83627thg/early_serial.c b/src/superio/winbond/w83627thg/early_serial.c
index 8ba1a308ae..cc84738e49 100644
--- a/src/superio/winbond/w83627thg/early_serial.c
+++ b/src/superio/winbond/w83627thg/early_serial.c
@@ -21,22 +21,23 @@
  */
 
 #include <arch/io.h>
+#include <device/pnp.h>
 #include "w83627thg.h"
 
-static void pnp_enter_ext_func_mode(device_t dev)
+void pnp_enter_ext_func_mode(device_t dev)
 {
 	u16 port = dev >> 8;
 	outb(0x87, port);
 	outb(0x87, port);
 }
 
-static void pnp_exit_ext_func_mode(device_t dev)
+void pnp_exit_ext_func_mode(device_t dev)
 {
 	u16 port = dev >> 8;
 	outb(0xaa, port);
 }
 
-static void inline w83627thg_enable_serial(device_t dev, u16 iobase)
+void w83627thg_enable_serial(device_t dev, u16 iobase)
 {
 	pnp_enter_ext_func_mode(dev);
 	pnp_set_logical_device(dev);
diff --git a/src/superio/winbond/w83627thg/w83627thg.h b/src/superio/winbond/w83627thg/w83627thg.h
index 8077de463b..a5cc450052 100644
--- a/src/superio/winbond/w83627thg/w83627thg.h
+++ b/src/superio/winbond/w83627thg/w83627thg.h
@@ -34,6 +34,10 @@
 #define W83627THG_ACPI            10
 #define W83627THG_HWM             11   /* Hardware monitor */
 
-void w83627thg_set_clksel_48(device_t dev);
+void pnp_enter_ext_func_mode(device_t dev);
+void pnp_exit_ext_func_mode(device_t dev);
 
-#endif
+void w83627thg_set_clksel_48(device_t dev);
+void w83627thg_enable_serial(device_t dev, u16 iobase);
+
+#endif /* SUPERIO_WINBOND_W83627THG_W83627THG_H */