drm: arm: hdlcd: Use drm_atomic_helper_shutdown() to disable planes on removal

The plane cleanup handler currently calls drm_plane_helper_disable(),
which is a legacy helper function. Replace it with a call to
drm_atomic_helper_shutdown() at removal time. The plane .destroy()
handler now consisting only of a call to drm_plane_cleanup(), replace it
with direct calls to that function.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>

drivers/gpu/drm/arm/hdlcd_crtc.c

@@ -280,16 +280,10 @@ static const struct drm_plane_helper_funcs hdlcd_plane_helper_funcs = {
 	.atomic_update = hdlcd_plane_atomic_update,
 };
 
-static void hdlcd_plane_destroy(struct drm_plane *plane)
-{
-	drm_plane_helper_disable(plane, NULL);
-	drm_plane_cleanup(plane);
-}
-
 static const struct drm_plane_funcs hdlcd_plane_funcs = {
 	.update_plane		= drm_atomic_helper_update_plane,
 	.disable_plane		= drm_atomic_helper_disable_plane,
-	.destroy		= hdlcd_plane_destroy,
+	.destroy		= drm_plane_cleanup,
 	.reset			= drm_atomic_helper_plane_reset,
 	.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
 	.atomic_destroy_state	= drm_atomic_helper_plane_destroy_state,

drivers/gpu/drm/arm/hdlcd_drv.c

@@ -355,6 +355,7 @@ static void hdlcd_drm_unbind(struct device *dev)
 	pm_runtime_put_sync(drm->dev);
 	pm_runtime_disable(drm->dev);
 	of_reserved_mem_device_release(drm->dev);
+	drm_atomic_helper_shutdown(drm);
 	drm_mode_config_cleanup(drm);
 	drm_dev_put(drm);
 	drm->dev_private = NULL;