From a9ca6e13d66042b3ac18d1352b88b7cd0da8fc21 Mon Sep 17 00:00:00 2001 From: "Ahmed S. Darwish" Date: Mon, 2 Feb 2015 15:15:55 -0500 Subject: [PATCH] can: kvaser_usb: Ignore spurious error events after a busoff Sending data in high speed then introducing a busoff results in spurious BUS_ERROR events from the USBCan-II firmware directly _after_ the triggered BUS_OFF event. In the current CAN state handling code, this will lead to an invalid can state of ACTIVE, ERROR, or PASSIVE even though the CAN controller has been already shut down due to the busoff. Guard the state handling code from such invalid events. Signed-off-by: Ahmed S. Darwish Signed-off-by: Marc Kleine-Budde --- drivers/net/can/usb/kvaser_usb.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/drivers/net/can/usb/kvaser_usb.c b/drivers/net/can/usb/kvaser_usb.c index 17d28d7dd412..2928f7003041 100644 --- a/drivers/net/can/usb/kvaser_usb.c +++ b/drivers/net/can/usb/kvaser_usb.c @@ -11,7 +11,7 @@ * Copyright (C) 2002-2006 KVASER AB, Sweden. All rights reserved. * Copyright (C) 2010 Matthias Fuchs , esd gmbh * Copyright (C) 2012 Olivier Sobrie - * Copyright (C) 2015 Valeo A.S. + * Copyright (C) 2015 Valeo S.A. */ #include @@ -824,14 +824,15 @@ static void kvaser_usb_rx_error_update_can_state(struct kvaser_usb_net_priv *pri else if (es->status & M16C_STATE_BUS_PASSIVE) new_state = CAN_STATE_ERROR_PASSIVE; else if (es->status & M16C_STATE_BUS_ERROR) { - if ((es->txerr >= 256) || (es->rxerr >= 256)) - new_state = CAN_STATE_BUS_OFF; - else if ((es->txerr >= 128) || (es->rxerr >= 128)) - new_state = CAN_STATE_ERROR_PASSIVE; - else if ((es->txerr >= 96) || (es->rxerr >= 96)) - new_state = CAN_STATE_ERROR_WARNING; - else if (cur_state > CAN_STATE_ERROR_ACTIVE) - new_state = CAN_STATE_ERROR_ACTIVE; + /* Guard against spurious error events after a busoff */ + if (cur_state < CAN_STATE_BUS_OFF) { + if ((es->txerr >= 128) || (es->rxerr >= 128)) + new_state = CAN_STATE_ERROR_PASSIVE; + else if ((es->txerr >= 96) || (es->rxerr >= 96)) + new_state = CAN_STATE_ERROR_WARNING; + else if (cur_state > CAN_STATE_ERROR_ACTIVE) + new_state = CAN_STATE_ERROR_ACTIVE; + } } if (!es->status) -- 2.39.5