diff --git a/libc/kernel/uapi/linux/can/isotp.h b/libc/kernel/uapi/linux/can/isotp.h
index dd5e4f5..57d3001 100644
--- a/libc/kernel/uapi/linux/can/isotp.h
+++ b/libc/kernel/uapi/linux/can/isotp.h
@@ -59,11 +59,12 @@
 #define CAN_ISOTP_DEFAULT_FLAGS 0
 #define CAN_ISOTP_DEFAULT_EXT_ADDRESS 0x00
 #define CAN_ISOTP_DEFAULT_PAD_CONTENT 0xCC
-#define CAN_ISOTP_DEFAULT_FRAME_TXTIME 0
+#define CAN_ISOTP_DEFAULT_FRAME_TXTIME 50000
 #define CAN_ISOTP_DEFAULT_RECV_BS 0
 #define CAN_ISOTP_DEFAULT_RECV_STMIN 0x00
 #define CAN_ISOTP_DEFAULT_RECV_WFTMAX 0
 #define CAN_ISOTP_DEFAULT_LL_MTU CAN_MTU
 #define CAN_ISOTP_DEFAULT_LL_TX_DL CAN_MAX_DLEN
 #define CAN_ISOTP_DEFAULT_LL_TX_FLAGS 0
+#define CAN_ISOTP_FRAME_TXTIME_ZERO 0xFFFFFFFF
 #endif