Re: [PATCH v2 1/1] can: ucan: add driver for Theobroma Systems UCAN devices

[Wolfgang Grandegger]

Am 14.03.2018 um 10:17 schrieb Wolfgang Grandegger:
> Am 14.03.2018 um 10:14 schrieb Jakob Unterwurzacher:
> > On 14.03.18 10:11, Wolfgang Grandegger wrote:
> > > > +ÂÂÂ /* handle error frames */
> > > > +ÂÂÂ canid = le32_to_cpu(m->msg.can_msg.id);
> > > > +ÂÂÂ if (canid & CAN_ERR_FLAG) {
> > > > +ÂÂÂÂÂÂÂ ucan_handle_error_frame(up, m, canid);
> > > > +ÂÂÂÂÂÂÂ /* drop frame if berr-reporting is off */
> > > > +ÂÂÂÂÂÂÂ if (!(up->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
> > > > +ÂÂÂÂÂÂÂÂÂÂÂ return;
> > > > +ÂÂÂ }
> > >
> > > You still do not generate error messages for state changes, IIUC.
> >
> > The hardware generates error frames on state changes - is that what 
> > you mean?
> >
> > In our testing, the state shows up (and updates) correctly in
> >
> > ÂÂÂÂÂip -details -statistics link show can0
>
> Counting the state changes is one thing but you should also generate 
> error messages for them.

The usual test here is:

$ candump -td -e any,0:0,#FFFFFFFF

should report proper state changes, if you send messages with

1. no cable connected
2. CAN high and low short-circuited

Also downwards if the hardware error is gone and you continue to send 
messages.

Wolfgang.