drm/omap: Use drm_fb_helper_lastclose() and _poll_changed()

This driver can use drm_fb_helper_lastclose() as its .lastclose callback.
It can also use drm_fb_helper_output_poll_changed() as its
.output_poll_changed callback.

Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171205182504.41923-9-noralf@tronnes.org

drivers/gpu/drm/omapdrm/omap_drv.c

@@ -46,14 +46,6 @@
  *                 devices
  */
 
-static void omap_fb_output_poll_changed(struct drm_device *dev)
-{
-	struct omap_drm_private *priv = dev->dev_private;
-	DBG("dev=%p", dev);
-	if (priv->fbdev)
-		drm_fb_helper_hotplug_event(priv->fbdev);
-}
-
 static void omap_atomic_wait_for_completion(struct drm_device *dev,
 					    struct drm_atomic_state *old_state)
 {
@@ -132,7 +124,7 @@ static const struct drm_mode_config_helper_funcs omap_mode_config_helper_funcs =
 
 static const struct drm_mode_config_funcs omap_mode_config_funcs = {
 	.fb_create = omap_framebuffer_create,
-	.output_poll_changed = omap_fb_output_poll_changed,
+	.output_poll_changed = drm_fb_helper_output_poll_changed,
 	.atomic_check = drm_atomic_helper_check,
 	.atomic_commit = drm_atomic_helper_commit,
 };
@@ -467,28 +459,6 @@ static int dev_open(struct drm_device *dev, struct drm_file *file)
 	return 0;
 }
 
-/**
- * lastclose - clean up after all DRM clients have exited
- * @dev: DRM device
- *
- * Take care of cleaning up after all DRM clients have exited.  In the
- * mode setting case, we want to restore the kernel's initial mode (just
- * in case the last client left us in a bad state).
- */
-static void dev_lastclose(struct drm_device *dev)
-{
-	struct omap_drm_private *priv = dev->dev_private;
-	int ret;
-
-	DBG("lastclose: dev=%p", dev);
-
-	if (priv->fbdev) {
-		ret = drm_fb_helper_restore_fbdev_mode_unlocked(priv->fbdev);
-		if (ret)
-			DBG("failed to restore crtc mode");
-	}
-}
-
 static const struct vm_operations_struct omap_gem_vm_ops = {
 	.fault = omap_gem_fault,
 	.open = drm_gem_vm_open,
@@ -511,7 +481,7 @@ static struct drm_driver omap_drm_driver = {
 	.driver_features = DRIVER_MODESET | DRIVER_GEM  | DRIVER_PRIME |
 		DRIVER_ATOMIC | DRIVER_RENDER,
 	.open = dev_open,
-	.lastclose = dev_lastclose,
+	.lastclose = drm_fb_helper_lastclose,
 #ifdef CONFIG_DEBUG_FS
 	.debugfs_init = omap_debugfs_init,
 #endif