drm/atomic: Return commit in drm_crtc_commit_get for better annotation

This will allow code to do x->commit = drm_crtc_commit_get(commit),
making it clearer where references are used.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170904104838.23822-5-maarten.lankhorst@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/drm_atomic_helper.c

@@ -1633,8 +1633,7 @@ static int stall_checks(struct drm_crtc *crtc, bool nonblock)
 				return -EBUSY;
 			}
 		} else if (i == 1) {
-			stall_commit = commit;
-			drm_crtc_commit_get(stall_commit);
+			stall_commit = drm_crtc_commit_get(commit);
 			break;
 		}
 

include/drm/drm_atomic.h

@@ -252,10 +252,14 @@ void __drm_crtc_commit_free(struct kref *kref);
  * @commit: CRTC commit
  *
  * Increases the reference of @commit.
+ *
+ * Returns:
+ * The pointer to @commit, with reference increased.
  */
-static inline void drm_crtc_commit_get(struct drm_crtc_commit *commit)
+static inline struct drm_crtc_commit *drm_crtc_commit_get(struct drm_crtc_commit *commit)
 {
 	kref_get(&commit->ref);
+	return commit;
 }
 
 /**