diff --git a/xf86drmMode.c b/xf86drmMode.c
index 87e96603..6b79d768 100644
--- a/xf86drmMode.c
+++ b/xf86drmMode.c
@@ -1348,7 +1348,7 @@ drm_public drmModeAtomicReqPtr drmModeAtomicAlloc(void)
 	return req;
 }
 
-drm_public drmModeAtomicReqPtr drmModeAtomicDuplicate(drmModeAtomicReqPtr old)
+drm_public drmModeAtomicReqPtr drmModeAtomicDuplicate(const drmModeAtomicReqPtr old)
 {
 	drmModeAtomicReqPtr new;
 
@@ -1378,7 +1378,7 @@ drm_public drmModeAtomicReqPtr drmModeAtomicDuplicate(drmModeAtomicReqPtr old)
 }
 
 drm_public int drmModeAtomicMerge(drmModeAtomicReqPtr base,
-                                  drmModeAtomicReqPtr augment)
+                                  const drmModeAtomicReqPtr augment)
 {
 	uint32_t i;
 
@@ -1411,7 +1411,7 @@ drm_public int drmModeAtomicMerge(drmModeAtomicReqPtr base,
 	return 0;
 }
 
-drm_public int drmModeAtomicGetCursor(drmModeAtomicReqPtr req)
+drm_public int drmModeAtomicGetCursor(const drmModeAtomicReqPtr req)
 {
 	if (!req)
 		return -EINVAL;
@@ -1480,7 +1480,7 @@ static int sort_req_list(const void *misc, const void *other)
 		return first->cursor - second->cursor;
 }
 
-drm_public int drmModeAtomicCommit(int fd, drmModeAtomicReqPtr req,
+drm_public int drmModeAtomicCommit(int fd, const drmModeAtomicReqPtr req,
                                    uint32_t flags, void *user_data)
 {
 	drmModeAtomicReqPtr sorted;
diff --git a/xf86drmMode.h b/xf86drmMode.h
index 19bf91dd..08557642 100644
--- a/xf86drmMode.h
+++ b/xf86drmMode.h
@@ -433,18 +433,18 @@ extern int drmModeObjectSetProperty(int fd, uint32_t object_id,
 typedef struct _drmModeAtomicReq drmModeAtomicReq, *drmModeAtomicReqPtr;
 
 extern drmModeAtomicReqPtr drmModeAtomicAlloc(void);
-extern drmModeAtomicReqPtr drmModeAtomicDuplicate(drmModeAtomicReqPtr req);
+extern drmModeAtomicReqPtr drmModeAtomicDuplicate(const drmModeAtomicReqPtr req);
 extern int drmModeAtomicMerge(drmModeAtomicReqPtr base,
-			      drmModeAtomicReqPtr augment);
+			      const drmModeAtomicReqPtr augment);
 extern void drmModeAtomicFree(drmModeAtomicReqPtr req);
-extern int drmModeAtomicGetCursor(drmModeAtomicReqPtr req);
+extern int drmModeAtomicGetCursor(const drmModeAtomicReqPtr req);
 extern void drmModeAtomicSetCursor(drmModeAtomicReqPtr req, int cursor);
 extern int drmModeAtomicAddProperty(drmModeAtomicReqPtr req,
 				    uint32_t object_id,
 				    uint32_t property_id,
 				    uint64_t value);
 extern int drmModeAtomicCommit(int fd,
-			       drmModeAtomicReqPtr req,
+			       const drmModeAtomicReqPtr req,
 			       uint32_t flags,
 			       void *user_data);