[PATCH] arm: ep93xx: Enable i2c support for ep9302

[Martin Guy]

On 11 June 2012 23:50, Ryan Mallon <rmallon at gmail.com> wrote:
> On 12/06/12 01:45, H Hartley Sweeten wrote:
>
>> On Sunday, June 10, 2012 4:58 PM, Ryan Mallon wrote:
>>> On 10/06/12 22:44, Todor Colov wrote:
>>>>
>>>> Enable i2c support for ep9302. i2c support is needed when external RTC is
>>>> used.
>>>>
>>>> Signed-off-by: Todor Colov <todorcolov at gmail.com>
>>>
>>> Thanks. Applied to ep93xx-fixes.
>>
>> Ryan,
>>
>> I'm not sure about this patch...
>>
>> The EDB9302 does not have a built-on external RTC connected to the I2C
>> bus. The EECLK and EEDAT pins are simply routed to two headers. They are
>> not connected to any I2C devices built onto the board.
>>
>> This patch will cause _all_ edb9302 boards to bind the ds1337 driver to the
>> I2C bus but that device will only exist if a user has connected the part
>> externally to the board.
>>
>> Just my 2 cents...
>
>
> Hmm, the binding is not really a problem, since it will just fail if the
> ds1337 device is not present at that i2c address. I guess the main problem
> is if there are users of the edb9302 who want i2c on the headers and others
> who want to use the pins as gpio. Without being able to auto-detect such
> boards at runtime (which seems very unlikely) I can't think of a good
> solution to this, other than it being time for me to do more DT reading :-).
>
> I'm inclined to leave the patch in. The ep93xx doesn't have a lot of users,
> so I think it is okay to tailor it a bit to the users we do have. I'm happy
> to revert it, and find a better solution if this breaks someone else's
> setup.

Hi folks
 Can I add that the SimpleMachines.it Sim.One board, based on the
EP9307, has a DS1337 on the I2C bus, for which the define is
machine_is_sim_one()  However, the existing Linux kernel already
read/writes this chip successfully, so I'm not sure what advantage
this change would bring for that board.  If you would like to test
your patch on that board too, we may be able to ship you an enginering
sample; if that would be useful please reply by private email.

Cheers

    M