umc-bus.c: fix usage of device_trylock

Fix usage of device_trylock. It has the same semantics of mutex_trylock, so it
returns 1 if the lock has been acquired successfully.

Signed-off-by: Claudio Scordino <claudio@evidence.eu.com>
Signed-off-by: Bruno Morelli <bruno@evidence.eu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/uwb/umc-bus.c b/drivers/uwb/umc-bus.c
index 82a84d5..5c5b3fc 100644
--- a/drivers/uwb/umc-bus.c
+++ b/drivers/uwb/umc-bus.c
@@ -63,7 +63,7 @@
 	struct device *parent = umc->dev.parent;
 	int ret = 0;
 
-	if (device_trylock(parent))
+	if (!device_trylock(parent))
 		return -EAGAIN;
 	ret = device_for_each_child(parent, parent, umc_bus_pre_reset_helper);
 	if (ret >= 0)