diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c
index a731fa66e504..60ae6f029499 100644
--- a/drivers/base/power/opp/core.c
+++ b/drivers/base/power/opp/core.c
@@ -11,6 +11,8 @@
  * published by the Free Software Foundation.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/errno.h>
 #include <linux/err.h>
 #include <linux/slab.h>
diff --git a/drivers/base/power/opp/cpu.c b/drivers/base/power/opp/cpu.c
index 7654c5606307..c27a1cdffec9 100644
--- a/drivers/base/power/opp/cpu.c
+++ b/drivers/base/power/opp/cpu.c
@@ -10,6 +10,9 @@
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/cpu.h>
 #include <linux/cpufreq.h>
 #include <linux/err.h>