-extras_hid2hci_hid2hci_SOURCES = extras/hid2hci/hid2hci.c
-extras_hid2hci_hid2hci_CPPFLAGS = $(AM_CPPFLAGS) $(LIBUSB_CFLAGS)
-extras_hid2hci_hid2hci_LDADD = libudev/libudev-private.la $(LIBUSB_LIBS)
-
-extras_udev_acl_udev_acl_SOURCES = extras/udev-acl/udev-acl.c
-extras_udev_acl_udev_acl_CPPFLAGS = $(AM_CPPFLAGS) $(GLIB_CFLAGS)
-extras_udev_acl_udev_acl_LDADD = libudev/libudev-private.la -lacl $(GLIB_LIBS)
-
-extras_usb_db_usb_db_SOURCES = extras/usb-db/usb-db.c
-extras_usb_db_usb_db_CPPFLAGS = $(AM_CPPFLAGS) -DUSB_DATABASE=\"$(USB_DATABASE)\" -DBUILD_FOR_USB
-extras_usb_db_usb_db_LDADD = libudev/libudev-private.la
-
-extras_usb_db_pci_db_SOURCES = extras/usb-db/usb-db.c
-extras_usb_db_pci_db_CPPFLAGS = $(AM_CPPFLAGS) -DPCI_DATABASE=\"$(USB_DATABASE)\" -DBUILD_FOR_PCI
-extras_usb_db_pci_db_LDADD = libudev/libudev-private.la
-
-extras_modem_modeswitch_modem_modeswitch_SOURCES =\
- extras/modem-modeswitch/modem-modeswitch.c \
- extras/modem-modeswitch/utils.c \
- extras/modem-modeswitch/utils.h \
- extras/modem-modeswitch/ma8280p_us.c \
- extras/modem-modeswitch/ma8280p_us.h \
- extras/modem-modeswitch/option.c \
- extras/modem-modeswitch/option.h
-extras_modem_modeswitch_modem_modeswitch_CPPFLAGS = $(AM_CPPFLAGS) $(LIBUSB_CFLAGS)
-extras_modem_modeswitch_modem_modeswitch_LDADD = libudev/libudev-private.la $(LIBUSB_LIBS)
-
-extras_keymap_keymap_SOURCES = extras/keymap/keymap.c
-extras_keymap_keymap_CPPFLAGS = $(AM_CPPFLAGS) -I extras/keymap
-nodist_extras_keymap_keymap_SOURCES = \
- extras/keymap/keys-from-name.h \
- extras/keymap/keys-to-name.h
+if ENABLE_EXTRAS
+# ------------------------------------------------------------------------------
+# conditional extras (need glib, libusb, libacl, ...)
+# ------------------------------------------------------------------------------
+dist_udevrules_DATA += \
+ rules/rules.d/75-net-description.rules \
+ rules/rules.d/75-tty-description.rules \
+ rules/rules.d/78-sound-card.rules