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Diffstat (limited to 'include/uapi/linux/can/isotp.h')
-rw-r--r--include/uapi/linux/can/isotp.h28
1 files changed, 22 insertions, 6 deletions
diff --git a/include/uapi/linux/can/isotp.h b/include/uapi/linux/can/isotp.h
index c55935b64ccc..590f8aea2b6d 100644
--- a/include/uapi/linux/can/isotp.h
+++ b/include/uapi/linux/can/isotp.h
@@ -137,20 +137,16 @@ struct can_isotp_ll_options {
#define CAN_ISOTP_WAIT_TX_DONE 0x400 /* wait for tx completion */
#define CAN_ISOTP_SF_BROADCAST 0x800 /* 1-to-N functional addressing */
-/* default values */
+/* protocol machine default values */
#define CAN_ISOTP_DEFAULT_FLAGS 0
#define CAN_ISOTP_DEFAULT_EXT_ADDRESS 0x00
#define CAN_ISOTP_DEFAULT_PAD_CONTENT 0xCC /* prevent bit-stuffing */
-#define CAN_ISOTP_DEFAULT_FRAME_TXTIME 0
+#define CAN_ISOTP_DEFAULT_FRAME_TXTIME 50000 /* 50 micro seconds */
#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
-
/*
* Remark on CAN_ISOTP_DEFAULT_RECV_* values:
*
@@ -162,4 +158,24 @@ struct can_isotp_ll_options {
* consistency and copied directly into the flow control (FC) frame.
*/
+/* link layer default values => make use of Classical CAN frames */
+
+#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
+
+/*
+ * The CAN_ISOTP_DEFAULT_FRAME_TXTIME has become a non-zero value as
+ * it only makes sense for isotp implementation tests to run without
+ * a N_As value. As user space applications usually do not set the
+ * frame_txtime element of struct can_isotp_options the new in-kernel
+ * default is very likely overwritten with zero when the sockopt()
+ * CAN_ISOTP_OPTS is invoked.
+ * To make sure that a N_As value of zero is only set intentional the
+ * value '0' is now interpreted as 'do not change the current value'.
+ * When a frame_txtime of zero is required for testing purposes this
+ * CAN_ISOTP_FRAME_TXTIME_ZERO u32 value has to be set in frame_txtime.
+ */
+#define CAN_ISOTP_FRAME_TXTIME_ZERO 0xFFFFFFFF
+
#endif /* !_UAPI_CAN_ISOTP_H */