Re: arbitration lost error reporting

[Richard Andrysek <richard.andrysek@rg-mechatronics.com>]

Wolfgang Grandegger <wg <at> grandegger.com> writes:

...
> >> big change of going mainline. The implementation is similar to
> >> CAN_CTRLMODE_BERR_REPORTING, just look for it in the kernel source tree
> >> and add a new define for arbitration lost error reporting.
> >>
> >> Do you have a preferred name for the define?
> >> - CAN_CTRLMODE_AERR_REPORTING
> >> - CAN_CTRLMODE_ARBITRATIONERR_REPORTING to
> > 
> > Loosing the arbitration is not an error. It just can happen from time to
time.
> 
> Well, if it does not happen often, why do we want to suppress reporting
> this error? I still do not see what it's good for.
> 
> Wolfgang.
> 
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> 

How do you define not often? Is it not often one time per ~130us? For X
channels you should divide it through X. Please assume this case stochastic
=> not always. 
Next if the information is for an application irrelevant, why I need to
generate an IRQ and use CPU resources?

How to fight with such case:

1) Use time triggered protocol - not always possible 
2) Slow done communication - not always possible
3) Buy faster machine - not always possible
4) Combination of 1..4 - ...

or

5) Let a freedom to a programmer, for the price that he shall to know it.