Index: src/hid/platform/Linux/OFGameController.m
==================================================================
--- src/hid/platform/Linux/OFGameController.m
+++ src/hid/platform/Linux/OFGameController.m
@@ -397,10 +397,12 @@
 - (void)retrieveState
 {
 	struct input_event event;
 
 	for (;;) {
+		OFGameControllerButton button;
+
 		errno = 0;
 
 		if (read(_fd, &event, sizeof(event)) < (int)sizeof(event)) {
 			if (errno == EWOULDBLOCK)
 				return;
@@ -411,16 +413,17 @@
 					  errNo: errno];
 		}
 
 		switch (event.type) {
 		case EV_KEY:
-			if (event.value)
-				[_pressedButtons addObject: buttonToName(
-				    event.code, _vendorID, _productID)];
-			else
-				[_pressedButtons removeObject: buttonToName(
-				    event.code, _vendorID, _productID)];
+			if ((button = buttonToName(event.code, _vendorID,
+			    _productID)) != nil) {
+				if (event.value)
+					[_pressedButtons addObject: button];
+				else
+					[_pressedButtons removeObject: button];
+			}
 			break;
 		case EV_ABS:
 			switch (event.code) {
 			case ABS_X:
 				_leftAnalogStickPosition.x = scale(event.value,