drm/bridge_connector: implement oob_hotplug_event

Implement the oob_hotplug_event() callback. Translate it to the HPD
notification sent to the HPD bridge in the chain.

Reviewed-by: Janne Grunau <j@jannau.net>
Link: https://lore.kernel.org/r/20231009174048.2695981-4-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231009174048.2695981-4-dmitry.baryshkov@linaro.org

drivers/gpu/drm/drm_bridge_connector.c

@@ -5,6 +5,8 @@
 
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/of.h>
+#include <linux/property.h>
 #include <linux/slab.h>
 
 #include <drm/drm_atomic_state_helper.h>
@@ -107,10 +109,9 @@ static void drm_bridge_connector_hpd_notify(struct drm_connector *connector,
 	}
 }
 
-static void drm_bridge_connector_hpd_cb(void *cb_data,
-					enum drm_connector_status status)
+static void drm_bridge_connector_handle_hpd(struct drm_bridge_connector *drm_bridge_connector,
+					    enum drm_connector_status status)
 {
-	struct drm_bridge_connector *drm_bridge_connector = cb_data;
 	struct drm_connector *connector = &drm_bridge_connector->base;
 	struct drm_device *dev = connector->dev;
 
@@ -123,6 +124,21 @@ static void drm_bridge_connector_hpd_cb(void *cb_data,
 	drm_kms_helper_connector_hotplug_event(connector);
 }
 
+static void drm_bridge_connector_hpd_cb(void *cb_data,
+					enum drm_connector_status status)
+{
+	drm_bridge_connector_handle_hpd(cb_data, status);
+}
+
+static void drm_bridge_connector_oob_hotplug_event(struct drm_connector *connector,
+						   enum drm_connector_status status)
+{
+	struct drm_bridge_connector *bridge_connector =
+		to_drm_bridge_connector(connector);
+
+	drm_bridge_connector_handle_hpd(bridge_connector, status);
+}
+
 static void drm_bridge_connector_enable_hpd(struct drm_connector *connector)
 {
 	struct drm_bridge_connector *bridge_connector =
@@ -191,6 +207,8 @@ static void drm_bridge_connector_destroy(struct drm_connector *connector)
 	drm_connector_unregister(connector);
 	drm_connector_cleanup(connector);
 
+	fwnode_handle_put(connector->fwnode);
+
 	kfree(bridge_connector);
 }
 
@@ -216,6 +234,7 @@ static const struct drm_connector_funcs drm_bridge_connector_funcs = {
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 	.debugfs_init = drm_bridge_connector_debugfs_init,
+	.oob_hotplug_event = drm_bridge_connector_oob_hotplug_event,
 };
 
 /* -----------------------------------------------------------------------------
@@ -352,6 +371,12 @@ struct drm_connector *drm_bridge_connector_init(struct drm_device *drm,
 		if (!drm_bridge_get_next_bridge(bridge))
 			connector_type = bridge->type;
 
+#ifdef CONFIG_OF
+		if (!drm_bridge_get_next_bridge(bridge) &&
+		    bridge->of_node)
+			connector->fwnode = fwnode_handle_get(of_fwnode_handle(bridge->of_node));
+#endif
+
 		if (bridge->ddc)
 			ddc = bridge->ddc;