drm/ast: Add detect function support

The existence of the connector cannot be detected,
so add the detect function to support.
Signed-off-by: Ainux <ainux.wang@gmail.com>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210526111515.40015-1-ainux.wang@gmail.com

drivers/gpu/drm/ast/ast_mode.c

@@ -1293,6 +1293,18 @@ static enum drm_mode_status ast_mode_valid(struct drm_connector *connector,
 	return flags;
 }
 
+static enum drm_connector_status ast_connector_detect(struct drm_connector
+						   *connector, bool force)
+{
+	int r;
+
+	r = ast_get_modes(connector);
+	if (r < 0)
+		return connector_status_disconnected;
+
+	return connector_status_connected;
+}
+
 static void ast_connector_destroy(struct drm_connector *connector)
 {
 	struct ast_connector *ast_connector = to_ast_connector(connector);
@@ -1307,6 +1319,7 @@ static const struct drm_connector_helper_funcs ast_connector_helper_funcs = {
 
 static const struct drm_connector_funcs ast_connector_funcs = {
 	.reset = drm_atomic_helper_connector_reset,
+	.detect = ast_connector_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = ast_connector_destroy,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
@@ -1334,7 +1347,8 @@ static int ast_connector_init(struct drm_device *dev)
 	connector->interlace_allowed = 0;
 	connector->doublescan_allowed = 0;
 
-	connector->polled = DRM_CONNECTOR_POLL_CONNECT;
+	connector->polled = DRM_CONNECTOR_POLL_CONNECT |
+						DRM_CONNECTOR_POLL_DISCONNECT;
 
 	drm_connector_attach_encoder(connector, encoder);
 
@@ -1403,6 +1417,8 @@ int ast_mode_config_init(struct ast_private *ast)
 
 	drm_mode_config_reset(dev);
 
+	drm_kms_helper_poll_init(dev);
+
 	return 0;
 }