thodg/cgminer

diff --git a/cgminer.c b/cgminer.c
index 76d586b..16e1b68 100644
--- a/cgminer.c
+++ b/cgminer.c
@@ -8402,6 +8402,7 @@ static void hotplug_process(void)
 			thr->device_thread = j;
 
 			if (cgpu->drv->thread_prepare && !cgpu->drv->thread_prepare(thr)) {
+				null_device_drv(cgpu->drv);
 				cgpu->deven = DEV_DISABLED;
 				continue;
 			}