Hi,
On 11/27/20 11:30 AM, Marc Kleine-Budde wrote:
On 11/27/20 10:59 AM, Jeroen Hofstee wrote:
Losing arbitration is normal in a CAN-bus network, it means that a
higher priority frame is being send and the pending message will be
retried later. Hence most driver only increment arbitration_lost, but
the sja1000 and sun4i driver also incremeant tx_error, causing errors
to be reported on a normal functioning CAN-bus. So stop counting them
as errors.
Sounds plausible.
For completeness, the Kvaser USB hybra also increments the tx_error
on arbitration lose, but it does so in single shot. Since in that
case the message is not retried, that behaviour is kept.
You mean only in one shot mode?
Yes, well at least the function is called kvaser_usb_hydra_one_shot_fail.
What about one shot mode on the sja1000 cores?
That is a good question. I guess it will be counted as error by:
if (isrc & IRQ_TI) {
/* transmission buffer released */
if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT &&
!(status & SR_TCS)) {
stats->tx_errors++;
can_free_echo_skb(dev, 0);
} else {
/* transmission complete */
stats->tx_bytes +=
priv->read_reg(priv, SJA1000_FI) & 0xf;
stats->tx_packets++;
can_get_echo_skb(dev, 0);
}
netif_wake_queue(dev);
can_led_event(dev, CAN_LED_EVENT_TX);
}
From the datasheet, Transmit Interrupt:
"set; this bit is set whenever the transmit bufferstatus
changes from ‘0-to-1’ (released) and the TIE bit is set
within the interrupt enable register".
I cannot test it though, since I don't have a sja1000.
Signed-off-by: Jeroen Hofstee <jhofstee@xxxxxxxxxxxxxxxxx>
I've split this into two patches, and added Fixes: lines, and pushed this for
now to linux-can/sja1000.
Thanks, regards,
Jeroen
