Re: [RFC v5] CAN FD support

[Oliver Hartkopp <socketcan@hartkopp.net>]

On 11.06.2012 16:26, Wolfgang Grandegger wrote:

> On 05/28/2012 10:02 PM, Oliver Hartkopp wrote:
>> Hi all,
>>
>> since RFC v4 - see http://marc.info/?l=linux-can&m=133708871921901&w=2 from
>> 2012-05-15 - i cleaned up some details and added the support of simultaneous
>> CAN and CANFD frame handling inside the networking code after some discussion
>> with Kurt. Sometimes code needs to be implemented to see that there is a more
>> elegant solution out there when removing that code again ;-)
>>
>> If you also feel fine with this patch i would finally create a patchset of
>> four patches, like 
>>
>> - adding new structures and constants
>> - adding CAN FD support in af_can.c
>> - adding CAN FD support in raw.c
>> - adding CAN FD support in vcan.c
>>
>> for the upcoming net-next bound for Linux 3.6 .
> 
> Do you have already CAN FD hardware for testing? If not, do we really
> want to have this patchset mainline.


Yes. There's a good reason for this patchset.

As you might remember from the old days ...

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=history;f=drivers/net/can/Kconfig

2009-05-18 	Wolfgang Grandegger	can: CAN Network device driver and Netlink interface 	blob | commitdiff | diff to current

2008-01-28 	Oliver Hartkopp	[CAN]: Add virtual CAN netdevice driver 	blob | commitdiff | diff to current

it was nearly 16 month the PF_CAN infrastructure was part of the mainline
kernel until the first 'real' CAN drivers have been added to the tree.
Meanwhile the driver development inside and outside the tree had a stable
environment for APIs and testing.

Same situation here. The CAN FD patches just provide a CAN FD capable
infrastructure with new data structures and extended userspace API which
allows to develop both drivers and CAN FD applications.

So when the patches go the usual way, they are released in Linux 3.6
somewhere in November/December this year - together with the first announced
real CAN FD hardware silicon. Btw. i assume that the first FPGA based CAN
controllers will be available for tests earlier.

So hitting this net-next window to provide CAN FD support in the netlayer
infrastructure is not too fast but right in time :-)

> More later...


Reviews are welcome.
Please check the different postings and discussions up to v5 before.

Regards,
Oliver