Setting CAN FD data bitrate with libsocketcan

Setting CAN FD data bitrate with libsocketcan

[André Hartmann]

Hi all,

libsocketcan [1] allows to set the CAN bus bitrate from an application 
with can_set_bitrate().

However, I did not find a possibility to set the CAN FD data bitrate.
Is there a way or does no such function exist yet? If it does not exist, 
are there plans to support it?

Thanks in advance,
André

[1] https://git.pengutronix.de/cgit/tools/libsocketcan/

Re: Setting CAN FD data bitrate with libsocketcan

[Lars Susaas]

> However, I did not find a possibility to set the CAN FD data bitrate.
> Is there a way or does no such function exist yet? If it does not exist, are
> there plans to support it?

Hi,

Was looking for the same thing a little while back.
Did not find it, so i made some changes to libsocketcan as part of my
work on canFestival (canOpen stack)

You can check out work here:
https://bitbucket.org/nimrof/canfestival-3-asc/src/53f18ae80f39901b61ddf6d04b9358893ac518db/drivers/can_socket?at=canfd

Just copy the following files into libsocketcan:
can_netlink.h
libsocketcan.c
libsocketcan.h

Its yet testet that well, so may contain bugs.

To set the databaudrate you have to set baudrate first with
'can_set_bitrate' then you can use 'can_set_data_bitrate'.

Feedback welcome

best regards
Lars

Re: Setting CAN FD data bitrate with libsocketcan

[André Hartmann]

Hi Lars,

thanks for your answer.

Am 10.09.2017 um 13:25 schrieb Lars Susaas:
>> However, I did not find a possibility to set the CAN FD data bitrate.
>> Is there a way or does no such function exist yet? If it does not exist, are
>> there plans to support it?
> 
> Hi,
> 
> Was looking for the same thing a little while back.
> Did not find it, so i made some changes to libsocketcan as part of my
> work on canFestival (canOpen stack)

Ah Ok, I like to use it for QtSerialBus [1]. Therefore I'm a bit limited 
with including 3rd party libraries (licenses and so) and we decided to 
use the system-wide libsocketcan. Which now turns out to miss (at least) 
one feature.

> You can check out work here:
> https://bitbucket.org/nimrof/canfestival-3-asc/src/53f18ae80f39901b61ddf6d04b9358893ac518db/drivers/can_socket?at=canfd
> 
> Just copy the following files into libsocketcan:
> can_netlink.h
> libsocketcan.c
> libsocketcan.h
> 
> Its yet testet that well, so may contain bugs.
> 
> To set the databaudrate you have to set baudrate first with
> 'can_set_bitrate' then you can use 'can_set_data_bitrate'.

I will definitely have a look this weekend. Have you considered 
upstreaming your changes back to libsocketcan?

Best regards,
André

[1] http://code.qt.io/cgit/qt/qtserialbus.git/

Re: Setting CAN FD data bitrate with libsocketcan

[Lars Susaas]

Hi André,


On Tue, Sep 12, 2017 at 9:26 PM, André Hartmann <aha_1980@gmx.de> wrote:
> I will definitely have a look this weekend. Have you considered upstreaming
> your changes back to libsocketcan?

Very nice if you have the time to check it out.
I definitely want to upstream, but i think it needs more testing and
maybe a cleanup of comments and code before that time.

My plan was first to get my changes to canFestival done and then turn
my focus to libsocketcan, but if other people have the need for
libsocketcan with can FD support i that will change :)

Best regards
Lars