diff --git a/test/dm/Makefile b/test/dm/Makefile
index fd781e8..9eaf04b 100644
--- a/test/dm/Makefile
+++ b/test/dm/Makefile
@@ -21,6 +21,7 @@
 obj-$(CONFIG_DM_GPIO) += gpio.o
 obj-$(CONFIG_DM_I2C) += i2c.o
 obj-$(CONFIG_LED) += led.o
+obj-$(CONFIG_DM_MAILBOX) += mailbox.o
 obj-$(CONFIG_DM_MMC) += mmc.o
 obj-$(CONFIG_DM_PCI) += pci.o
 obj-$(CONFIG_RAM) += ram.o