diff --git a/sys/modules/dpt/Makefile b/sys/modules/dpt/Makefile
index 3f681b0c0dfb..6f66d4488810 100644
--- a/sys/modules/dpt/Makefile
+++ b/sys/modules/dpt/Makefile
@@ -5,10 +5,30 @@
 KMOD=	dpt
 SRCS=	dpt_scsi.c dpt.h \
 	dpt_pci.c pci_if.h \
-	opt_dpt.h \
+	opt_dpt.h opt_eisa.h \
 	opt_cam.h opt_scsi.h \
 	device_if.h bus_if.h
-#SRCS+=	dpt_eisa.c eisa_if.h \
-#SRCS+=	dpt_isa.c isa_if.h \
+
+.if ${MACHINE} != "i386"
+# Create an empty opt_eisa.h in order to keep kmod.mk from linking in an
+# existing one from KERNBUILDDIR which possibly has DEV_EISA defined so
+# dpt.ko is always built without EISA support.
+opt_eisa.h:
+	:> ${.TARGET}
+.else
+.if !defined(KERNBUILDDIR)
+SRCS+=	dpt_eisa.c eisa_if.h
+#SRCS+=	dpt_isa.c isa_if.h
+
+opt_eisa.h:
+	echo "#define DEV_EISA 1" > ${.TARGET}
+.else
+DEV_EISA!= sed -n '/DEV_EISA/p' ${KERNBUILDDIR}/opt_eisa.h
+.if !empty(DEV_EISA)
+SRCS+=	dpt_eisa.c eisa_if.h
+.endif
+#SRCS+=	dpt_isa.c isa_if.h
+.endif
+.endif
 
 .include <bsd.kmod.mk>