drm/exynos: Remove custom FB helper deferred setup

The FB helper core now supports deferred setup, so the driver's custom
implementation can be removed.

v2: Drop NULL check, drm_fb_helper_hotplug_event handles that already.

Cc: Inki Dae <inki.dae@samsung.com>
Cc: Joonyoung Shim <jy0922.shim@samsung.com>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Thierry Reding <treding@nvidia.com> (v1)
Reviewed-by: Inki Dae <inki.dae@samsung.com>
Tested-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20170706130023.28417-4-daniel.vetter@ffwll.ch
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/exynos/exynos_drm_drv.c

@@ -395,8 +395,9 @@ static int exynos_drm_bind(struct device *dev)
 	/* init kms poll for handling hpd */
 	drm_kms_helper_poll_init(drm);
 
-	/* force connectors detection */
-	drm_helper_hpd_irq_event(drm);
+	ret = exynos_drm_fbdev_init(drm);
+	if (ret)
+		goto err_cleanup_poll;
 
 	/* register the DRM device */
 	ret = drm_dev_register(drm, 0);
@@ -407,6 +408,7 @@ static int exynos_drm_bind(struct device *dev)
 
 err_cleanup_fbdev:
 	exynos_drm_fbdev_fini(drm);
+err_cleanup_poll:
 	drm_kms_helper_poll_fini(drm);
 	exynos_drm_device_subdrv_remove(drm);
 err_unbind_all:

drivers/gpu/drm/exynos/exynos_drm_fbdev.c

@@ -183,24 +183,6 @@ static const struct drm_fb_helper_funcs exynos_drm_fb_helper_funcs = {
 	.fb_probe =	exynos_drm_fbdev_create,
 };
 
-static bool exynos_drm_fbdev_is_anything_connected(struct drm_device *dev)
-{
-	struct drm_connector *connector;
-	bool ret = false;
-
-	mutex_lock(&dev->mode_config.mutex);
-	list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
-		if (connector->status != connector_status_connected)
-			continue;
-
-		ret = true;
-		break;
-	}
-	mutex_unlock(&dev->mode_config.mutex);
-
-	return ret;
-}
-
 int exynos_drm_fbdev_init(struct drm_device *dev)
 {
 	struct exynos_drm_fbdev *fbdev;
@@ -211,9 +193,6 @@ int exynos_drm_fbdev_init(struct drm_device *dev)
 	if (!dev->mode_config.num_crtc || !dev->mode_config.num_connector)
 		return 0;
 
-	if (!exynos_drm_fbdev_is_anything_connected(dev))
-		return 0;
-
 	fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
 	if (!fbdev)
 		return -ENOMEM;
@@ -304,8 +283,5 @@ void exynos_drm_output_poll_changed(struct drm_device *dev)
 	struct exynos_drm_private *private = dev->dev_private;
 	struct drm_fb_helper *fb_helper = private->fb_helper;
 
-	if (fb_helper)
-		drm_fb_helper_hotplug_event(fb_helper);
-	else
-		exynos_drm_fbdev_init(dev);
+	drm_fb_helper_hotplug_event(fb_helper);
 }