diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index eb792cb..bcb793e 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -183,6 +183,7 @@
 	struct work_struct	clk_gate_work; /* delayed clock gate */
 	unsigned int		clk_old;	/* old clock value cache */
 	spinlock_t		clk_lock;	/* lock for clk fields */
+	struct mutex		clk_gate_mutex;	/* mutex for clock gating */
 #endif
 
 	/* host specific block data */