drm/mediatek: mtk_hdmi_common: Defer probe when ddc i2c bus isn't available yet

The i2c adapter for ddc might not be available yet due to e.g. its
module not yet being loaded. To handle that defer probing rather then
returning a fatal error when probing.

Signed-off-by: Sjoerd Simons <sjoerd@collabora.com>
Signed-off-by: Louis-Alexis Eyraud <louisalexis.eyraud@collabora.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

Author: sjoerdsimons

drivers/gpu/drm/mediatek/mtk_hdmi_common.c

@@ -331,7 +331,7 @@ static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi, struct platform_device
 	hdmi->ddc_adpt = of_find_i2c_adapter_by_node(i2c_np);
 	of_node_put(i2c_np);
 	if (!hdmi->ddc_adpt)
-		return dev_err_probe(dev, -EINVAL, "Failed to get ddc i2c adapter by node\n");
+		return dev_err_probe(dev, -EPROBE_DEFER, "Failed to get ddc i2c adapter by node\n");
 
 	ret = devm_add_action_or_reset(dev, mtk_hdmi_put_device, &hdmi->ddc_adpt->dev);
 	if (ret)