diff --git a/artiq/firmware/libboard/ad9154.rs b/artiq/firmware/libboard/ad9154.rs
index de1ce565a..83b6eeacf 100644
--- a/artiq/firmware/libboard/ad9154.rs
+++ b/artiq/firmware/libboard/ad9154.rs
@@ -1,5 +1,5 @@
 use csr;
-use ad9154_reg::reg;
+mod ad9154_reg;
 
 fn spi_setup() {
     unsafe {
diff --git a/artiq/firmware/libboard/ad9516.rs b/artiq/firmware/libboard/ad9516.rs
index 375a2411d..a67c86774 100644
--- a/artiq/firmware/libboard/ad9516.rs
+++ b/artiq/firmware/libboard/ad9516.rs
@@ -1,5 +1,5 @@
 use csr;
-use ad9516_reg::reg;
+mod ad9516_reg;
 
 fn spi_setup() {
     unsafe {