diff options
| author | Ahmed S. Darwish <ahmed.darwish@valeo.com> | 2015-01-26 07:25:43 +0200 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2015-02-08 20:01:54 +0100 |
| commit | a38a9696988b01a496af60ca7494068865bb2217 (patch) | |
| tree | d9c6457516d9b21b830a8eb96dda0dc8511ced45 | |
| parent | 3d6365501fe636c82771ee41727f96d0e281a70f (diff) | |
| download | lwn-a38a9696988b01a496af60ca7494068865bb2217.tar.gz lwn-a38a9696988b01a496af60ca7494068865bb2217.zip | |
can: kvaser_usb: Fix state handling upon BUS_ERROR events
commit e638642b08c170d2021b706f0b1c4f4ae93d8cbd upstream.
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 <ahmed.darwish@valeo.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
| -rw-r--r-- | 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 5ea0de87514b..a3fb8b51038a 100644 --- a/drivers/net/can/usb/kvaser_usb.c +++ b/drivers/net/can/usb/kvaser_usb.c @@ -690,9 +690,7 @@ 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; @@ -702,7 +700,8 @@ 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; |