From 0ae18a82686f9b9965a8ce0dd81371871b306ffe Mon Sep 17 00:00:00 2001 From: Zhang Changzhong Date: Wed, 5 Aug 2020 11:50:25 +0800 Subject: [PATCH] can: j1939: add rxtimer for multipacket broadcast session According to SAE J1939/21 (Chapter 5.12.3 and APPENDIX C), for transmit side the required time interval between packets of a multipacket broadcast message is 50 to 200 ms, the responder shall use a timeout of 250ms (provides margin allowing for the maximumm spacing of 200ms). For receive side a timeout will occur when a time of greater than 750 ms elapsed between two message packets when more packets were expected. So this patch fix and add rxtimer for multipacket broadcast session. Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol") Signed-off-by: Zhang Changzhong Link: https://lore.kernel.org/r/1596599425-5534-5-git-send-email-zhangchangzhong@huawei.com Acked-by: Oleksij Rempel Signed-off-by: Marc Kleine-Budde --- net/can/j1939/transport.c | 28 ++++++++++++++++++++-------- 1 file changed, 20 insertions(+), 8 deletions(-) diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c index 047118d5270b..a8dd956b5e8e 100644 --- a/net/can/j1939/transport.c +++ b/net/can/j1939/transport.c @@ -723,10 +723,12 @@ static int j1939_session_tx_rts(struct j1939_session *session) return ret; session->last_txcmd = dat[0]; - if (dat[0] == J1939_TP_CMD_BAM) + if (dat[0] == J1939_TP_CMD_BAM) { j1939_tp_schedule_txtimer(session, 50); - - j1939_tp_set_rxtimeout(session, 1250); + j1939_tp_set_rxtimeout(session, 250); + } else { + j1939_tp_set_rxtimeout(session, 1250); + } netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); @@ -1687,11 +1689,15 @@ static void j1939_xtp_rx_rts(struct j1939_priv *priv, struct sk_buff *skb, } session->last_cmd = cmd; - j1939_tp_set_rxtimeout(session, 1250); - - if (cmd != J1939_TP_CMD_BAM && !session->transmission) { - j1939_session_txtimer_cancel(session); - j1939_tp_schedule_txtimer(session, 0); + if (cmd == J1939_TP_CMD_BAM) { + if (!session->transmission) + j1939_tp_set_rxtimeout(session, 750); + } else { + if (!session->transmission) { + j1939_session_txtimer_cancel(session); + j1939_tp_schedule_txtimer(session, 0); + } + j1939_tp_set_rxtimeout(session, 1250); } j1939_session_put(session); @@ -1742,6 +1748,7 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session, int offset; int nbytes; bool final = false; + bool remain = false; bool do_cts_eoma = false; int packet; @@ -1817,6 +1824,8 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session, j1939_cb_is_broadcast(&session->skcb)) { if (session->pkt.rx >= session->pkt.total) final = true; + else + remain = true; } else { /* never final, an EOMA must follow */ if (session->pkt.rx >= session->pkt.last) @@ -1826,6 +1835,9 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session, if (final) { j1939_session_timers_cancel(session); j1939_session_completed(session); + } else if (remain) { + if (!session->transmission) + j1939_tp_set_rxtimeout(session, 750); } else if (do_cts_eoma) { j1939_tp_set_rxtimeout(session, 1250); if (!session->transmission) -- 2.39.5