On Wed, 21 Jan 2015 10:36:47 -0500, "Ahmed S. Darwish" <darwish...@gmail.com> wrote: > On Wed, Jan 21, 2015 at 03:00:15PM +0000, Andri Yngvason wrote: >> Quoting Ahmed S. Darwish (2015-01-21 14:43:23) >> > Hi! > > ... > >> > <-- Unplug the cable --> >> > >> > (000.009106) can0 20000080 [8] 00 00 00 00 00 00 08 00 >> > ERRORFRAME >> > bus-error >> > error-counter-tx-rx{{8}{0}} >> > (000.001872) can0 20000080 [8] 00 00 00 00 00 00 10 00
For a bus-errors I would also expcect some more information in the data[2..3] fields. But these are always zero. >> > ERRORFRAME >> > bus-error >> > error-counter-tx-rx{{16}{0}} >> [...] >> > error-counter-tx-rx{{80}{0}} >> > (000.001910) can0 20000080 [8] 00 00 00 00 00 00 58 00 >> > ERRORFRAME >> > bus-error >> > error-counter-tx-rx{{88}{0}} >> > (000.001753) can0 20000084 [8] 00 08 00 00 00 00 60 00 >> > ERRORFRAME >> > controller-problem{tx-error-warning} >> Good. >> > bus-error >> > error-counter-tx-rx{{96}{0}} > > Nice. > >> > (000.001720) can0 20000080 [8] 00 00 00 00 00 00 68 00 >> > ERRORFRAME >> > bus-error >> > error-counter-tx-rx{{104}{0}} >> > (000.001876) can0 20000080 [8] 00 00 00 00 00 00 70 00 >> > ERRORFRAME >> > bus-error >> > error-counter-tx-rx{{112}{0}} >> > (000.001749) can0 20000080 [8] 00 00 00 00 00 00 78 00 >> > ERRORFRAME >> > bus-error >> > error-counter-tx-rx{{120}{0}} >> > (000.001771) can0 20000084 [8] 00 20 00 00 00 00 80 00 >> > ERRORFRAME >> > controller-problem{tx-error-passive} >> Also good. >> > bus-error >> > error-counter-tx-rx{{128}{0}} > > Also nice :-) > >> > (000.001868) can0 20000080 [8] 00 00 00 00 00 00 80 00 >> > ERRORFRAME >> > bus-error >> > error-counter-tx-rx{{128}{0}} >> > (000.001982) can0 20000080 [8] 00 00 00 00 00 00 80 00 >> > ERRORFRAME >> > bus-error >> > error-counter-tx-rx{{128}{0}} >> > >> > (( Then a continous flood, exactly similar to the above packet, >> > appears. >> > Unfortunately this flooding is a firmware problem. )) >> > >> > <-- Replug the cable, after a good amount of time --> >> > >> Where are the reverse state transitions? >> > > > Hmmm... > > [ ... ] >> >> Reverse state transitions are missing from the logs. See comments above. >> > > When the device is on the _receiving_ end, and I unplug the CAN cable after > introducing some noise to the level of reaching WARNING or PASSIVE, I > receive a BUS_ERROR event with the rxerr count reset back to 0 or 1. In > that case, the driver correctly transitions back the state to ERROR_ACTIVE > and candump produces something similar to: > > (000.000362) can0 2000008C [8] 00 40 40 00 00 00 00 01 > ERRORFRAME > controller-problem{} > protocol-violation{{back-to-error-active}{}} > bus-error > error-counter-tx-rx{{0}{1}} > > which is, AFAIK, the correct behaviour from the driver side. > > Meanwhile, when the device is on the _sending_ end and I re-plug the CAN > cable again. Sometimes I receive events with txerr reset to 0 or 1, and > the driver correctly reverts back to ERROR_ACTIVE in that case. But on > another times like the quoted case above, I don't receive any events > resetting txerr back -- only data packets on the bus. Well, the firmware seems to report *only* bus-errors via CMD_CAN_ERROR_EVENT messages, also carrying the new state, but no CMD_CHIP_STATE_EVENT just for the state changes. > So, What can the driver do given the above? Little if the notification does not come. Wolfgang. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/