From mboxrd@z Thu Jan  1 00:00:00 1970
From: Oliver Hartkopp <socketcan@hartkopp.net>
Subject: Re: GS_USB
Date: Mon, 11 Nov 2013 16:41:38 +0100
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To: "Max S." <max@schneidersoft.net>
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>> Manual recovery is not supported. The node can leave bus off state if
> 
>> it detects 128 occurrences of 11 consecutive recessive bits on the bus.
> 
>> Maybe I can trick the controller out of bus off by doing a software
> 
>> reset. That's probably not going to be a clean solution though.
> 
> 
> 
> Would be nice if manual recovery is supported but it's not a requirement.
> 
> Maybe you could make the delay before restarting bus-off configurable
> 
> using the "restart-ms" argument.
> 
> 
> 
> For further information have a look to:
> 
> 
> 
> http://lxr.free-electrons.com/source/Documentation/networking/can.txt#L891
> 
> 

Yes.

Usually the CAN controller sits in BUS_OFF until it detects correct CAN frames
_or_ until the controller is re-initialized.

The CAN controller should not recover itself as this might be wrong depending
on the use-case.

Therefore the manual "restart" can be initiated by some user application or it
can be handled inside the driver e.g. 200ms after a BUS_OFF detection by the
"restart-ms" option.

Regards,
Oliver