[PATCH v2] i2c: core: make it possible to match a pure device tree driver

[Linus Walleij]

On Fri, Jun 7, 2013 at 11:32 PM, Wolfram Sang <wsa at the-dreams.de> wrote:
> ...
>> I2C devices probed from device tree should subsequently be
>> fixed to handle the case where of_match_table() is
>> used (I think none of them do that today), and platforms should
>> fix their device trees to use compatible strings for I2C devices
>> instead of setting the name to Linux device driver names as is
>> done in multiple cases today.
>
> I guess your solution is the least intrusive one. Still, it could happen
> that of_match_table is scanned three times (by driver core, i2c layer,
> and i2c driver) which is IMO an indication to look for a more elegant
> solution tp find out what really matched?

I think that is a generic problem with the device tree
being completely stateless, and rather a comment on the
of_match_device() intrinsics being inelegant than on this
patch?

Do you see it as a blocker for the patch?

What happens before this patch is that instead of looping
over the of_match_table, the id_table is always iterated
to the end also in the DT case, yielding NULL as the last
argument to driver->probe() anyway.

Maybe the OF people have some comments on this...
I cannot really see how it could be any different given
the way the FDT works :-/

Yours,
Linus Walleij