Re: [PATCH v5 2/5] can: kvaser_usb: Consolidate and unify state change handling

From: Andri Yngvason
Date: Wed Jan 21 2015 - 10:00:46 EST


Quoting Ahmed S. Darwish (2015-01-21 14:43:23)
> Hi!
>
> On Wed, Jan 21, 2015 at 12:53:58PM +0100, Wolfgang Grandegger wrote:
> > On Wed, 21 Jan 2015 10:33:19 +0000, Andri Yngvason
> > <andri.yngvason@xxxxxxxxx> wrote:
> > > Quoting Ahmed S. Darwish (2015-01-20 21:45:37)
> > >> From: Ahmed S. Darwish <ahmed.darwish@xxxxxxxxx>
> > >>
> > >> Replace most of the can interface's state and error counters
> > >> handling with the new can-dev can_change_state() mechanism.
> > >>
> > >> Suggested-by: Andri Yngvason <andri.yngvason@xxxxxxxxx>
> > >> Signed-off-by: Ahmed S. Darwish <ahmed.darwish@xxxxxxxxx>
> > >> ---
> > >> drivers/net/can/usb/kvaser_usb.c | 114
> > >> +++++++++++++++++++--------------------
> > >> 1 file changed, 55 insertions(+), 59 deletions(-)
> > >>
> > >> diff --git a/drivers/net/can/usb/kvaser_usb.c
> > >> b/drivers/net/can/usb/kvaser_usb.c
> > >> index 971c5f9..0386d3f 100644
> > >> --- a/drivers/net/can/usb/kvaser_usb.c
> > >> +++ b/drivers/net/can/usb/kvaser_usb.c
> >
> > ...
> > >
> > > Looks good.
> >
> > Would be nice to see some "candump" traces as well.
>
> Sure. The USBCan-II device trace below is generated after applying
> all patches in the series, especially patch #3, which fixes some
> some invalid CAN state transitions logic in the original driver.
[...]
>
> Afterwards, candump on a PC, Kvaser USB device on the sending end:
>
> ...
> (000.008784) can0 60A [1] C1
> (000.011341) can0 2A8 [8] C2 0A 00 00 00 00 00 00
> (000.009873) can0 03D [7] C3 0A 00 00 00 00 00
> (000.010394) can0 55C [8] C4 0A 00 00 00 00 00 00
> (000.009979) can0 45A [8] C5 0A 00 00 00 00 00 00
> (000.010125) can0 6E8 [8] C6 0A 00 00 00 00 00 00
> (000.010149) can0 4EE [8] C7 0A 00 00 00 00 00 00
> (000.010102) can0 5D2 [8] C8 0A 00 00 00 00 00 00
> (000.010000) can0 61F [8] C9 0A 00 00 00 00 00 00
> (000.010271) can0 5F8 [8] CA 0A 00 00 00 00 00 00
>
> <-- 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 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}}
> (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}}
> (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?
>
> (000.520485) can0 33D [4] CB 0A 00 00
> (000.002693) can0 42E [8] CC 0A 00 00 00 00 00 00
> (000.001795) can0 319 [4] CD 0A 00 00
> (000.002705) can0 3B1 [8] CE 0A 00 00 00 00 00 00
> (000.001295) can0 4CC [2] CF 0A
> (000.002205) can0 42B [6] D0 0A 00 00 00 00
> (000.001620) can0 5A2 [3] D1 0A 00
> (000.002636) can0 691 [8] D2 0A 00 00 00 00 00 00
> (000.002615) can0 36A [8] D3 0A 00 00 00 00 00 00
> (000.001729) can0 068 [4] D4 0A 00 00
> (000.001195) can0 4C8 [1] D5
> ...
>
> ##########################################################################
>
> Bus-off Testing:
>
> candump on a PC, Kvaser device on the sending end. An i.mx6 ARM
> board with flexcan is on the receiving end:
>
> (000.010319) can0 5CC [8] 90 02 00 00 00 00 00 00
> (000.008747) can0 679 [1] 91
> (000.011442) can0 011 [8] 92 02 00 00 00 00 00 00
> (000.008991) can0 631 [2] 93 02
> (000.011097) can0 532 [7] 94 02 00 00 00 00 00
> (000.009781) can0 0A9 [5] 95 02 00 00 00
> (000.010792) can0 1DD [8] 96 02 00 00 00 00 00 00
> (000.010026) can0 44E [8] 97 02 00 00 00 00 00 00
> (000.010181) can0 76A [8] 98 02 00 00 00 00 00 00
> (000.008867) can0 1A5 [1] 99
> (000.011322) can0 2B4 [8] 9A 02 00 00 00 00 00 00
>
> <-- Unplug the can low and high wires from the board -->
>
> (000.009688) can0 20000080 [8] 00 00 00 00 00 00 08 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{8}{0}}
> (000.002246) can0 20000080 [8] 00 00 00 00 00 00 10 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{16}{0}}
> (000.002124) can0 20000080 [8] 00 00 00 00 00 00 18 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{24}{0}}
> (000.002115) can0 20000080 [8] 00 00 00 00 00 00 20 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{32}{0}}
> (000.002132) can0 20000080 [8] 00 00 00 00 00 00 28 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{40}{0}}
> (000.002266) can0 20000080 [8] 00 00 00 00 00 00 30 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{48}{0}}
> (000.002187) can0 20000080 [8] 00 00 00 00 00 00 38 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{56}{0}}
> (000.002046) can0 20000080 [8] 00 00 00 00 00 00 40 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{64}{0}}
> (000.002076) can0 20000080 [8] 00 00 00 00 00 00 48 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{72}{0}}
> (000.002406) can0 20000080 [8] 00 00 00 00 00 00 50 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{80}{0}}
> (000.001969) can0 20000080 [8] 00 00 00 00 00 00 58 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{88}{0}}
> (000.002388) can0 20000084 [8] 00 08 00 00 00 00 60 00 ERRORFRAME
> controller-problem{tx-error-warning}
> bus-error
> error-counter-tx-rx{{96}{0}}
> (000.002021) can0 20000080 [8] 00 00 00 00 00 00 68 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{104}{0}}
> (000.002110) can0 20000080 [8] 00 00 00 00 00 00 70 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{112}{0}}
> (000.002155) can0 20000080 [8] 00 00 00 00 00 00 78 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{120}{0}}
> (000.002140) can0 20000084 [8] 00 20 00 00 00 00 80 00 ERRORFRAME
> controller-problem{tx-error-passive}
> bus-error
> error-counter-tx-rx{{128}{0}}
> (000.002324) can0 20000080 [8] 00 00 00 00 00 00 80 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{128}{0}}
> (000.002416) can0 20000080 [8] 00 00 00 00 00 00 80 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{128}{0}}
> (000.002237) 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 ))
>
> <-- Short-circuit the can high and low wires -->
>
> (000.002364) can0 20000080 [8] 00 00 00 00 00 00 80 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{128}{0}}
> (000.002108) can0 20000080 [8] 00 00 00 00 00 00 88 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{136}{0}}
> (000.000494) can0 20000080 [8] 00 00 00 00 00 00 90 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{144}{0}}
> (000.000523) can0 20000080 [8] 00 00 00 00 00 00 98 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{152}{0}}
> (000.000661) can0 20000080 [8] 00 00 00 00 00 00 A0 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{160}{0}}
> (000.000464) can0 20000080 [8] 00 00 00 00 00 00 A8 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{168}{0}}
> (000.000534) can0 20000080 [8] 00 00 00 00 00 00 B0 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{176}{0}}
> (000.000499) can0 20000080 [8] 00 00 00 00 00 00 B8 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{184}{0}}
> (000.000626) can0 20000080 [8] 00 00 00 00 00 00 C0 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{192}{0}}
> (000.000373) can0 20000080 [8] 00 00 00 00 00 00 C8 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{200}{0}}
> (000.000627) can0 20000080 [8] 00 00 00 00 00 00 D0 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{208}{0}}
> (000.000507) can0 20000080 [8] 00 00 00 00 00 00 D8 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{216}{0}}
> (000.000501) can0 20000080 [8] 00 00 00 00 00 00 E0 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{224}{0}}
> (000.000459) can0 20000080 [8] 00 00 00 00 00 00 E8 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{232}{0}}
> (000.000606) can0 20000080 [8] 00 00 00 00 00 00 F0 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{240}{0}}
> (000.000454) can0 20000080 [8] 00 00 00 00 00 00 F8 00 ERRORFRAME
> bus-error
> error-counter-tx-rx{{248}{0}}
> (000.000664) can0 200000C0 [8] 00 00 00 00 00 00 00 00 ERRORFRAME
> bus-off
> bus-error
>
> (( No further bus activity ))
>
Bus-off seems OK. You could have just short circuited them without
disconnecting.

Reverse state transitions are missing from the logs. See comments above.

--
Andri
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/