extern int drm_mode_page_flip_ioctl(struct drm_device *dev,
void *data, struct drm_file *file_priv);
extern struct drm_display_mode *drm_cvt_mode(struct drm_device *dev,
extern int drm_mode_page_flip_ioctl(struct drm_device *dev,
void *data, struct drm_file *file_priv);
extern struct drm_display_mode *drm_cvt_mode(struct drm_device *dev,