4 files changed, 28 insertions, 15 deletions

diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index 7ff13bc47ca..b7adb4a967f 100644
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -714,6 +714,27 @@ EXPORT_SYMBOL(drm_mode_set_crtcinfo);
 
 
 /**
+ * drm_mode_copy - copy the mode
+ * @dst: mode to overwrite
+ * @src: mode to copy
+ *
+ * LOCKING:
+ * None.
+ *
+ * Copy an existing mode into another mode, preserving the object id
+ * of the destination mode.
+ */
+void drm_mode_copy(struct drm_display_mode *dst, const struct drm_display_mode *src)
+{
+        int id = dst->base.id;
+
+        *dst = *src;
+        dst->base.id = id;
+        INIT_LIST_HEAD(&dst->head);
+}
+EXPORT_SYMBOL(drm_mode_copy);
+
+/**
  * drm_mode_duplicate - allocate and duplicate an existing mode
  * @m: mode to duplicate
  *
@@ -727,16 +748,13 @@ struct drm_display_mode *drm_mode_duplicate(struct drm_device *dev,
                                             const struct drm_display_mode *mode)
 {
         struct drm_display_mode *nmode;
-        int new_id;
 
         nmode = drm_mode_create(dev);
         if (!nmode)
                 return NULL;
 
-        new_id = nmode->base.id;
-        *nmode = *mode;
-        nmode->base.id = new_id;
-        INIT_LIST_HEAD(&nmode->head);
+        drm_mode_copy(nmode, mode);
+
         return nmode;
 }
 EXPORT_SYMBOL(drm_mode_duplicate);
diff --git a/drivers/gpu/drm/nouveau/nv50_dac.c b/drivers/gpu/drm/nouveau/nv50_dac.c
index a0f2bebf49e..55c56330be6 100644
--- a/drivers/gpu/drm/nouveau/nv50_dac.c
+++ b/drivers/gpu/drm/nouveau/nv50_dac.c
@@ -190,11 +190,8 @@ nv50_dac_mode_fixup(struct drm_encoder *encoder, struct drm_display_mode *mode,
         }
 
         if (connector->scaling_mode != DRM_MODE_SCALE_NONE &&
-             connector->native_mode) {
-                int id = adjusted_mode->base.id;
-                *adjusted_mode = *connector->native_mode;
-                adjusted_mode->base.id = id;
-        }
+             connector->native_mode)
+                drm_mode_copy(adjusted_mode, connector->native_mode);
 
         return true;
 }
diff --git a/drivers/gpu/drm/nouveau/nv50_sor.c b/drivers/gpu/drm/nouveau/nv50_sor.c
index 9a5c2c98658..a7844ab6a50 100644
--- a/drivers/gpu/drm/nouveau/nv50_sor.c
+++ b/drivers/gpu/drm/nouveau/nv50_sor.c
@@ -342,11 +342,8 @@ nv50_sor_mode_fixup(struct drm_encoder *encoder, struct drm_display_mode *mode,
         }
 
         if (connector->scaling_mode != DRM_MODE_SCALE_NONE &&
-             connector->native_mode) {
-                int id = adjusted_mode->base.id;
-                *adjusted_mode = *connector->native_mode;
-                adjusted_mode->base.id = id;
-        }
+             connector->native_mode)
+                drm_mode_copy(adjusted_mode, connector->native_mode);
 
         return true;
 }
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 53cb49a13e1..9595c2c9adc 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -855,6 +855,7 @@ extern struct edid *drm_get_edid(struct drm_connector *connector,
 extern int drm_add_edid_modes(struct drm_connector *connector, struct edid *edid);
 extern void drm_mode_probed_add(struct drm_connector *connector, struct drm_display_mode *mode);
 extern void drm_mode_remove(struct drm_connector *connector, struct drm_display_mode *mode);
+extern void drm_mode_copy(struct drm_display_mode *dst, const struct drm_display_mode *src);
 extern struct drm_display_mode *drm_mode_duplicate(struct drm_device *dev,
                                                    const struct drm_display_mode *mode);
 extern void drm_mode_debug_printmodeline(struct drm_display_mode *mode);