greybus: svc: connection is created only once now

We no longer create a fresh connection on receiving svc-hello message,
but rather update the initial one.

Update 'initial_svc_connection' after the connection is fully
initialized. Look for the partially initialized connection while
removing hd, as hd might be removed before getting svc-hello requests
from svc.

Also update gb_svc_connection_init() to initialize id_map on the first
(and the only) call to connection-init function.

We also can't update connection->bundle->intf->svc, as its a bundle-less
connection. Lets stop updating intf->svc as its not really used.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Perry Hung <perry@leaflabs.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/core.c

@@ -236,6 +236,12 @@ void greybus_remove_hd(struct greybus_host_device *hd)
 	gb_interfaces_remove(hd);
 	gb_endo_remove(hd->endo);
 
+	/* Is the SVC still using the partially uninitialized connection ? */
+	if (hd->initial_svc_connection) {
+		gb_connection_exit(hd->initial_svc_connection);
+		gb_connection_destroy(hd->initial_svc_connection);
+	}
+
 	/*
 	 * Make sure there are no leftovers that can potentially corrupt sysfs.
 	 */

drivers/staging/greybus/svc.c

@@ -54,6 +54,9 @@ gb_ap_interface_create(struct greybus_host_device *hd,
 	intf->device_id = GB_DEVICE_ID_AP;
 	svc_update_connection(intf, connection);
 
+	/* Its no longer a partially initialized connection */
+	hd->initial_svc_connection = NULL;
+
 	return intf;
 }
 
@@ -384,24 +387,11 @@ static int gb_svc_connection_init(struct gb_connection *connection)
 	svc->connection = connection;
 	connection->private = svc;
 
-	/*
-	 * SVC connection is created twice:
-	 * - before the interface-id of the AP and the endo type is known.
-	 * - after receiving endo type and interface-id of the AP from the SVC.
-	 *
-	 * We should do light-weight initialization for the first case.
-	 */
-	if (!connection->bundle) {
-		WARN_ON(connection->hd->initial_svc_connection);
-		connection->hd->initial_svc_connection = connection;
-		return 0;
-	}
+	WARN_ON(connection->hd->initial_svc_connection);
+	connection->hd->initial_svc_connection = connection;
 
 	ida_init(&greybus_svc_device_id_map);
 
-	/* Set interface's svc connection */
-	connection->bundle->intf->svc = svc;
-
 	return 0;
 }
 
@@ -409,14 +399,6 @@ static void gb_svc_connection_exit(struct gb_connection *connection)
 {
 	struct gb_svc *svc = connection->private;
 
-	if (connection->hd->initial_svc_connection == connection) {
-		connection->hd->initial_svc_connection = NULL;
-	} else {
-		if (WARN_ON(connection->bundle->intf->svc != svc))
-			return;
-		connection->bundle->intf->svc = NULL;
-	}
-
 	connection->private = NULL;
 	kfree(svc);
 }