[PATCH] can: j1939: fix wrong rx timeout for CTS hold messages

[Alexander Hölzl]

In J1939 segmented transport, a CTS message with data byte 2 set to zero is interpreted as a hold message.
This instructs the transmitter of the segmented message to hold the connection open but to delay sending.
According to the J1939-21 standard, section 5.10.2.4 the timeout T4 after which an held open session is invalidated is
1050 ms, not 550 as implemented currently.
The 550 ms are problematic if a device uses hold messages and assumes it can wait for more than 550 ms before it has
to resend the hold message.

This patch changes the T4 timeout used in the implementation from 550 ms to 1050.

Signed-off-by: Alexander Hölzl <alexander.hoelzl@xxxxxxx>
---
 net/can/j1939/transport.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index df93d57907da..7ad56b5f17b9 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c
@@ -1479,7 +1479,7 @@ j1939_xtp_rx_cts_one(struct j1939_session *session, struct sk_buff *skb)
 		}
 	} else {
 		/* CTS(0) */
-		j1939_tp_set_rxtimeout(session, 550);
+		j1939_tp_set_rxtimeout(session, 1050);
 	}
 	return;
 
-- 
2.43.0