drm/omap: dss: Functions to check components in the display/output list

The functions can be used to check a component (by it's of_node) if it is
part of the omapdss display or output list. If the component is found, it
means that the driver is loaded.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/gpu/drm/omapdrm/dss/display.c

@@ -132,6 +132,24 @@ void omapdss_unregister_display(struct omap_dss_device *dssdev)
 }
 EXPORT_SYMBOL(omapdss_unregister_display);
 
+bool omapdss_component_is_display(struct device_node *node)
+{
+	struct omap_dss_device *dssdev;
+	bool found = false;
+
+	mutex_lock(&panel_list_mutex);
+	list_for_each_entry(dssdev, &panel_list, panel_list) {
+		if (dssdev->dev->of_node == node) {
+			found = true;
+			goto out;
+		}
+	}
+out:
+	mutex_unlock(&panel_list_mutex);
+	return found;
+}
+EXPORT_SYMBOL(omapdss_component_is_display);
+
 struct omap_dss_device *omap_dss_get_device(struct omap_dss_device *dssdev)
 {
 	if (!try_module_get(dssdev->owner))

drivers/gpu/drm/omapdrm/dss/omapdss.h

@@ -936,4 +936,7 @@ struct dispc_ops {
 void dispc_set_ops(const struct dispc_ops *o);
 const struct dispc_ops *dispc_get_ops(void);
 
+bool omapdss_component_is_display(struct device_node *node);
+bool omapdss_component_is_output(struct device_node *node);
+
 #endif /* __OMAP_DRM_DSS_H */

drivers/gpu/drm/omapdrm/dss/output.c

@@ -107,6 +107,19 @@ void omapdss_unregister_output(struct omap_dss_device *out)
 }
 EXPORT_SYMBOL(omapdss_unregister_output);
 
+bool omapdss_component_is_output(struct device_node *node)
+{
+	struct omap_dss_device *out;
+
+	list_for_each_entry(out, &output_list, list) {
+		if (out->dev->of_node == node)
+			return true;
+	}
+
+	return false;
+}
+EXPORT_SYMBOL(omapdss_component_is_output);
+
 struct omap_dss_device *omap_dss_get_output(enum omap_dss_output_id id)
 {
 	struct omap_dss_device *out;