[PATCH RFC v2 15/24] drm/bridge: notify about detached bridges

[Luca Ceresoli]

In preparation to support DRM bridge hotplug, let the drm_bridge code emit
an event when a bridge is detached, so that this event can trigger the
actions needed to deconfigure the pipeline and unregister the connector as
appropriate.

Signed-off-by: Luca Ceresoli <luca.ceresoli at bootlin.com>
---
 drivers/gpu/drm/Kconfig      | 1 +
 drivers/gpu/drm/drm_bridge.c | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index e661241ed1df..17c86244c75a 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -17,6 +17,7 @@ menuconfig DRM
 # device and dmabuf fd. Let's make sure that is available for our userspace.
 	select KCMP
 	select VIDEO
+	select DRM_EVENT_NOTIFIER
 	help
 	  Kernel-level support for the Direct Rendering Infrastructure (DRI)
 	  introduced in XFree86 4.0. If you say Y here, you need to select
diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index c0a2f7f1ce62..c825e80b9a7f 100644
--- a/drivers/gpu/drm/drm_bridge.c
+++ b/drivers/gpu/drm/drm_bridge.c
@@ -34,6 +34,7 @@
 #include <drm/drm_debugfs.h>
 #include <drm/drm_edid.h>
 #include <drm/drm_encoder.h>
+#include <drm/drm_event_notifier.h>
 #include <drm/drm_file.h>
 #include <drm/drm_of.h>
 #include <drm/drm_print.h>
@@ -702,6 +703,9 @@ void drm_bridge_detach(struct drm_bridge *bridge)
 		bridge->funcs->detach(bridge);
 
 	list_del_init(&bridge->chain_node);
+
+	drm_event_notifier_notify(DRM_BRIDGE_DETACHED, bridge);
+
 	bridge->dev = NULL;
 	drm_bridge_put(bridge);
 }

-- 
2.55.0