mfd: Add missing mutex.h inclusion to WM8994 core.h
struct wm8994 includes a mutex so we need to include mutex.h before we
declare it. All current users rely on this being done implicitly.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/include/linux/mfd/wm8994/core.h b/include/linux/mfd/wm8994/core.h
index f44bdb7..8eb1b75 100644
--- a/include/linux/mfd/wm8994/core.h
+++ b/include/linux/mfd/wm8994/core.h
@@ -15,6 +15,7 @@
#ifndef __MFD_WM8994_CORE_H__
#define __MFD_WM8994_CORE_H__
+#include <linux/mutex.h>
#include <linux/interrupt.h>
enum wm8994_type {
