diff --git a/gnu/packages/libusb.scm b/gnu/packages/libusb.scm
index dd8a2ff23b..17f71eba8d 100644
--- a/gnu/packages/libusb.scm
+++ b/gnu/packages/libusb.scm
@@ -67,7 +67,8 @@ (define-public libmtp
     (build-system gnu-build-system)
     (native-inputs
      `(("pkg-config" ,pkg-config)))
-    (inputs
+    (propagated-inputs
+     ;; libmtp.pc refers to all these.
      `(("libgcrypt" ,libgcrypt)
        ("libusb" ,libusb)))
     (arguments