drm: kirin: Add register connect helper functions in drm init

As part of refactoring the kirin driver to better support
different hardware revisions, this patch adds a flag to the
device specific driver data so that we can conditionally
register the connectors at init.

Cc: Rongrong Zou <zourongrong@gmail.com>
Cc: Xinliang Liu <z.liuxinliang@hisilicon.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel <dri-devel@lists.freedesktop.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Xinliang Liu <z.liuxinliang@hisilicon.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Xu YiPing <xuyiping@hisilicon.com>
[jstultz: reworded commit message]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190820230626.23253-20-john.stultz@linaro.org

drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c

@@ -1073,6 +1073,7 @@ static struct drm_driver ade_driver = {
 };
 
 struct kirin_drm_data ade_driver_data = {
+	.register_connects = false,
 	.num_planes = ADE_CH_NUM,
 	.prim_plane = ADE_CH1,
 	.channel_formats = channel_formats,

drivers/gpu/drm/hisilicon/kirin/kirin_drm_drv.c

@@ -98,6 +98,40 @@ static int compare_of(struct device *dev, void *data)
 	return dev->of_node == data;
 }
 
+static int kirin_drm_connectors_register(struct drm_device *dev)
+{
+	struct drm_connector *connector;
+	struct drm_connector *failed_connector;
+	struct drm_connector_list_iter conn_iter;
+	int ret;
+
+	mutex_lock(&dev->mode_config.mutex);
+	drm_connector_list_iter_begin(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter) {
+		ret = drm_connector_register(connector);
+		if (ret) {
+			failed_connector = connector;
+			goto err;
+		}
+	}
+	drm_connector_list_iter_end(&conn_iter);
+	mutex_unlock(&dev->mode_config.mutex);
+
+	return 0;
+
+err:
+	drm_connector_list_iter_begin(dev, &conn_iter);
+	drm_for_each_connector_iter(connector, &conn_iter) {
+		if (failed_connector == connector)
+			break;
+		drm_connector_unregister(connector);
+	}
+	drm_connector_list_iter_end(&conn_iter);
+	mutex_unlock(&dev->mode_config.mutex);
+
+	return ret;
+}
+
 static int kirin_drm_bind(struct device *dev)
 {
 	struct drm_device *drm_dev;
@@ -117,8 +151,17 @@ static int kirin_drm_bind(struct device *dev)
 
 	drm_fbdev_generic_setup(drm_dev, 32);
 
+	/* connectors should be registered after drm device register */
+	if (driver_data->register_connects) {
+		ret = kirin_drm_connectors_register(drm_dev);
+		if (ret)
+			goto err_drm_dev_unregister;
+	}
+
 	return 0;
 
+err_drm_dev_unregister:
+	drm_dev_unregister(drm_dev);
 err_kms_cleanup:
 	kirin_drm_kms_cleanup(drm_dev);
 err_drm_dev_put:

drivers/gpu/drm/hisilicon/kirin/kirin_drm_drv.h

@@ -39,6 +39,7 @@ struct kirin_drm_data {
 	u32 channel_formats_cnt;
 	int config_max_width;
 	int config_max_height;
+	bool register_connects;
 	u32 num_planes;
 	u32 prim_plane;