drm/sun4i: Don't check for panel or bridge on TV TCONs

TV TCONs are always connected to TV or HDMI encoder, so it doesn't make
sense to check if panel or bridge is connected to them.

Check if TCON has channel 0 and only then check for connected panel or
bridges.

Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180625120304.7543-13-jernej.skrabec@siol.net

drivers/gpu/drm/sun4i/sun4i_tcon.c

@@ -1178,13 +1178,19 @@ static const struct component_ops sun4i_tcon_ops = {
 static int sun4i_tcon_probe(struct platform_device *pdev)
 {
 	struct device_node *node = pdev->dev.of_node;
+	const struct sun4i_tcon_quirks *quirks;
 	struct drm_bridge *bridge;
 	struct drm_panel *panel;
 	int ret;
 
-	ret = drm_of_find_panel_or_bridge(node, 1, 0, &panel, &bridge);
-	if (ret == -EPROBE_DEFER)
-		return ret;
+	quirks = of_device_get_match_data(&pdev->dev);
+
+	/* panels and bridges are present only on TCONs with channel 0 */
+	if (quirks->has_channel_0) {
+		ret = drm_of_find_panel_or_bridge(node, 1, 0, &panel, &bridge);
+		if (ret == -EPROBE_DEFER)
+			return ret;
+	}
 
 	return component_add(&pdev->dev, &sun4i_tcon_ops);
 }