drm/msm: 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: Rob Clark <robdclark@gmail.com>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171205182504.41923-7-noralf@tronnes.org

drivers/gpu/drm/msm/msm_drv.c

@@ -37,16 +37,9 @@
 #define MSM_VERSION_MINOR	3
 #define MSM_VERSION_PATCHLEVEL	0
 
-static void msm_fb_output_poll_changed(struct drm_device *dev)
-{
-	struct msm_drm_private *priv = dev->dev_private;
-	if (priv->fbdev)
-		drm_fb_helper_hotplug_event(priv->fbdev);
-}
-
 static const struct drm_mode_config_funcs mode_config_funcs = {
 	.fb_create = msm_framebuffer_create,
-	.output_poll_changed = msm_fb_output_poll_changed,
+	.output_poll_changed = drm_fb_helper_output_poll_changed,
 	.atomic_check = drm_atomic_helper_check,
 	.atomic_commit = msm_atomic_commit,
 	.atomic_state_alloc = msm_atomic_state_alloc,
@@ -551,13 +544,6 @@ static void msm_postclose(struct drm_device *dev, struct drm_file *file)
 	context_close(ctx);
 }
 
-static void msm_lastclose(struct drm_device *dev)
-{
-	struct msm_drm_private *priv = dev->dev_private;
-	if (priv->fbdev)
-		drm_fb_helper_restore_fbdev_mode_unlocked(priv->fbdev);
-}
-
 static irqreturn_t msm_irq(int irq, void *arg)
 {
 	struct drm_device *dev = arg;
@@ -866,7 +852,7 @@ static struct drm_driver msm_driver = {
 				DRIVER_MODESET,
 	.open               = msm_open,
 	.postclose           = msm_postclose,
-	.lastclose          = msm_lastclose,
+	.lastclose          = drm_fb_helper_lastclose,
 	.irq_handler        = msm_irq,
 	.irq_preinstall     = msm_irq_preinstall,
 	.irq_postinstall    = msm_irq_postinstall,