Merge tag 'v6.5-rc2' into sched/core, to pick up fixes

Sync with upstream fixes before applying EEVDF.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 21 insertions, 0 deletions

diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c
index f6292ba0e6fc..037e36f2049c 100644
--- a/drivers/gpu/drm/drm_client.c
+++ b/drivers/gpu/drm/drm_client.c
@@ -122,13 +122,34 @@ EXPORT_SYMBOL(drm_client_init);
  * drm_client_register() it is no longer permissible to call drm_client_release()
  * directly (outside the unregister callback), instead cleanup will happen
  * automatically on driver unload.
+ *
+ * Registering a client generates a hotplug event that allows the client
+ * to set up its display from pre-existing outputs. The client must have
+ * initialized its state to able to handle the hotplug event successfully.
  */
 void drm_client_register(struct drm_client_dev *client)
 {
 	struct drm_device *dev = client->dev;
+	int ret;
 
 	mutex_lock(&dev->clientlist_mutex);
 	list_add(&client->list, &dev->clientlist);
+
+	if (client->funcs && client->funcs->hotplug) {
+		/*
+		 * Perform an initial hotplug event to pick up the
+		 * display configuration for the client. This step
+		 * has to be performed *after* registering the client
+		 * in the list of clients, or a concurrent hotplug
+		 * event might be lost; leaving the display off.
+		 *
+		 * Hold the clientlist_mutex as for a regular hotplug
+		 * event.
+		 */
+		ret = client->funcs->hotplug(client);
+		if (ret)
+			drm_dbg_kms(dev, "client hotplug ret=%d\n", ret);
+	}
 	mutex_unlock(&dev->clientlist_mutex);
 }
 EXPORT_SYMBOL(drm_client_register);