diff --git a/dtool/Config.Linux.pp b/dtool/Config.Linux.pp
index c90e8cc9c8..0765c16ee1 100644
--- a/dtool/Config.Linux.pp
+++ b/dtool/Config.Linux.pp
@@ -319,6 +319,9 @@
 // Do we have <ucontext.h> (and therefore makecontext() / swapcontext())?
 #define HAVE_UCONTEXT_H 1
 
+// Do we have <linux/input.h> ? This enables us to use raw mouse input.
+#define HAVE_LINUX_INPUT_H 1
+
 // Do we have RTTI (and <typeinfo>)?
 #define HAVE_RTTI 1
 
diff --git a/dtool/LocalSetup.pp b/dtool/LocalSetup.pp
index 8841b57016..ccfdb661a8 100644
--- a/dtool/LocalSetup.pp
+++ b/dtool/LocalSetup.pp
@@ -602,6 +602,9 @@ $[cdefine HAVE_SYS_SOUNDCARD_H]
    swapcontext())? */
 $[cdefine HAVE_UCONTEXT_H]
 
+/* Do we have <linux/input.h> ? This enables us to use raw mouse input. */
+$[cdefine HAVE_LINUX_INPUT_H]
+
 /* Do we have RTTI (and <typeinfo>)? */
 $[cdefine HAVE_RTTI]