Hi Wolfgang,

> what is your plan now? Provide patches for mainline inclusion
> (net-next-2.6) or for the Socket-CAN SVN trunk? Please don't send
> patches for both. We can do the backport to the SVN trunk later.

Okay, I didn't know that this was acceptable. I thought we get the driver
straight first in socketcan-trunk and then put it to net-next. From the
development process, I'd like it a _lot_ more if I just could create my
git-branch and then post to the according mailing-lists, like ppc and netdev. I
didn't really dare to do this for this first round, as I didn't know who is
working on what and if there are already other plans for mscan and I didn't
want to interfere.

> > Note 1: It depends on changes to the clock-implementation of the MPC512x.
> > Those patches need to be discussed and approved on the ppc list and can be 
> > found here:
> > http://patchwork.ozlabs.org/patch/37417/
> > http://patchwork.ozlabs.org/patch/37427/
> > (If they work for you, I'd be happy about Acked-by-tags.)
> 
> My impression is that they will not be accepted as already a new clock
> interface is available (via patches).

As those patches you mentioned are in an early state, I think my additions
could be accepted for now. Also, for the mpc5xxx_can-part, there shouldn't be
much change, as it is still clk_get() and clk_enable() there.

> 
> > Note 2: If this approach is accepted, I will next do the remaining cleanup
> > work (giving the functions the proper 5xxx names, ...) as follow up patches 
> > to
> > hopefully get this driver into mainline soonish.
> 
> Would be nice to have that fixed a.s.a.p.

Yeah, in case I can use git and a the top-of-tree kernel version, this should
go more smoothly.

> >  Kconfig             |    8 +++---
> >  mscan/mpc52xx_can.c |   64 
> > +++++++++++++++++++++++++++++++++++++++++-----------
> >  mscan/mscan.h       |    3 +-
> >  3 files changed, 57 insertions(+), 18 deletions(-)
> 
> I assume this patch is for the SVN trunk. Please provide patches against
> top of tree, and not a subdirectory to ease testing.

Uh, ouch! I'm very sorry, seems like my svn-fu has dramatically dropped since 
git.

> > Index: mscan/mpc52xx_can.c
> 
> As said above, please do s/mpc52xx/mpc5xxx/ immediately. It does not
> harm if we have both, the old mpc52xx_can.c and the new mpc5xxx_can.c
> in the SVN trunk including the related CONFIG_CAN_* parameters. The
> mpc5xxx_can.c should not include the legacy driver stuff (pre-OF), of
> course.

OK.

> > +   cellp = of_get_property(ofdev->node, "cell-index", NULL);
> > +   if (!cellp)
> > +           return 0;
> 
> Hm, the mscan node does not have a cell-index any more because it's
> deprecated (removed by the device tree police), IIRC.

Using Grant's suggestion, this becomes obsolete.

> > +   if (port_clk)
> > +           return clk_get_rate(port_clk);
> > +   else
> > +           return clk_get_rate(mscan_clk);
> > +}
> 
> I have not looked into your clock patches, but how can the user select
> the clock source and the clock frequency (via clock divider)? This
> should be selectable via DTS file, I think.

This is not possible yet. For that, I wanted to wait until the
clock-representation in the device-tree (the patches you mentioned, I suppose)
stabilizes. If this matures, we can add the proper way to do it. For now,
"clock-ipb" is supported, the rest has to be done by the bootloader or
additional patches. I wouldn't like to introduce "intermediate" properties to
the device tree.

> 
> What's also missing is the proper bus-off recovery method for the
> MCP512x. Unfortunately, it's also not yet OK for the MPC5200. It should
> be implemented as listed below:
> 
> - if possible, automatic bus-off recovery should be turned off, which
>   is possible on the MPC512x (but not the default for compatibility with
>   the MPC5200.
> 
> - if bus-off recovery cannot be switched of, the driver should handle it
>   as follows:
> 
>   - if restart_ms == 0, the device should be stopped on bus-off to
>     suppress automatic recovery.
> 
>   - if restart_ms > 0, the hardware should do the automatic recovery and
>     a RESTARTED error message should be sent when it re-enters the
>     error-active state (or leaves the bus-off state).

Uh, I didn't find this in the TODO. That might beat my timeframe for this
project, as it surely needs lots of testing :( Maybe Fu can help me here, but
not sure...

Thanks for the feedback!

   Wolfram

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

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