[PATCH v6 4/7] can: kvaser_usb: Fix state handling upon BUS_ERROR events
From: Ahmed S. Darwish <hidden>
Date: 2015-01-26 05:25:51
Also in:
lkml, netdev
Subsystem:
can network drivers, the rest · Maintainers:
Marc Kleine-Budde, Vincent Mailhol, Linus Torvalds
From: Ahmed S. Darwish <redacted> While being in an ERROR_WARNING state, and receiving further bus error events with error counters still in the ERROR_WARNING range of 97-127 inclusive, the state handling code erroneously reverts back to ERROR_ACTIVE. Per the CAN standard, only revert to ERROR_ACTIVE when the error counters are less than 96. Moreover, in certain Kvaser models, the BUS_ERROR flag is always set along with undefined bits in the M16C status register. Thus use bitwise operators instead of full equality for checking that register against bus errors. Signed-off-by: Ahmed S. Darwish <redacted> --- drivers/net/can/usb/kvaser_usb.c | 7 +++---- 1 files changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/net/can/usb/kvaser_usb.c b/drivers/net/can/usb/kvaser_usb.c
index 55407b9..7af379c 100644
--- a/drivers/net/can/usb/kvaser_usb.c
+++ b/drivers/net/can/usb/kvaser_usb.c@@ -698,9 +698,7 @@ static void kvaser_usb_rx_error(const struct kvaser_usb *dev, } new_state = CAN_STATE_ERROR_PASSIVE; - } - - if (status == M16C_STATE_BUS_ERROR) { + } else if (status & M16C_STATE_BUS_ERROR) { if ((priv->can.state < CAN_STATE_ERROR_WARNING) && ((txerr >= 96) || (rxerr >= 96))) { cf->can_id |= CAN_ERR_CRTL;
@@ -710,7 +708,8 @@ static void kvaser_usb_rx_error(const struct kvaser_usb *dev, priv->can.can_stats.error_warning++; new_state = CAN_STATE_ERROR_WARNING; - } else if (priv->can.state > CAN_STATE_ERROR_ACTIVE) { + } else if ((priv->can.state > CAN_STATE_ERROR_ACTIVE) && + ((txerr < 96) && (rxerr < 96))) { cf->can_id |= CAN_ERR_PROT; cf->data[2] = CAN_ERR_PROT_ACTIVE;
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1.7.7.6