diff --git a/drivers/net/hamradio/6pack.c b/drivers/net/hamradio/6pack.c
index 86b3bb9..92420f0 100644
--- a/drivers/net/hamradio/6pack.c
+++ b/drivers/net/hamradio/6pack.c
@@ -914,7 +914,7 @@
 					printk(KERN_DEBUG "6pack: protocol violation\n");
 				else
 					sp->status = 0;
-				cmd &= !SIXP_RX_DCD_MASK;
+				cmd &= ~SIXP_RX_DCD_MASK;
 		}
 		sp->status = cmd & SIXP_PRIO_DATA_MASK;
 	} else { /* output watchdog char if idle */