[PATCH v3] mtd: spi-nor: add dt support for Everspin MRAMs

[Rafał Miłecki]

On 17 January 2017 at 14:57, Cyrille Pitchen <cyrille.pitchen at atmel.com> wrote:
> Le 17/01/2017 à 14:16, Rafał Miłecki a écrit :
>> On 17 January 2017 at 12:03, Uwe Kleine-König
>> <u.kleine-koenig at pengutronix.de> wrote:
>>> The MR25 family doesn't support JEDEC, so they need explicit mentioning
>>> in the list of supported spi IDs. This makes it possible to add these
>>> using for example:
>>>
>>>         compatible = "everspin,mr25h40";
>>
>> (...)
>>
>>> diff --git a/Documentation/devicetree/bindings/mtd/jedec,spi-nor.txt b/Documentation/devicetree/bindings/mtd/jedec,spi-nor.txt
>>> index 2c91c03e7eb0..3e920ec5c4d3 100644
>>> --- a/Documentation/devicetree/bindings/mtd/jedec,spi-nor.txt
>>> +++ b/Documentation/devicetree/bindings/mtd/jedec,spi-nor.txt
>>> @@ -14,6 +14,8 @@ Required properties:
>>>                   at25df641
>>>                   at26df081a
>>>                   mr25h256
>>> +                 mr25h10
>>> +                 mr25h40
>>>                   mx25l4005a
>>>                   mx25l1606e
>>>                   mx25l6405d
>>
>> Uh, this is getting a never-ending-story...
>> If these chipsets don't support JEDEC, should we keep them in jedec,spi-nor.txt?
>>
>
> Maybe not but I think the new compatible strings should be documented
> somewhere. Currently jedec,spi-nor.txt already documents all the
> "m25p*-nonjedec" memories. So maybe just renaming the jedec,spi-nor.txt
> file into spi-nor.txt or mtd,spi-nor.txt could be a solution. Otherwise, we
> can let it as is. I have no idea of what would be the best solution.
>
> To be honest, I don't always fully understand the DT policy/philosophy and
> its requirements. I just thought when a new property or a new value is
> introduced it has to be documented.
> Generally speaking, when DT is involved in some series of patches, it often
> generates many discussions about the proper way to do thinks and about
> choosing the best between many technically functional solutions.
>
> If you think jedec,spi-nor.txt is not suited to document the new value for
> the compatible string, why not, I perfectly understand your point.
>
> I don't mind choosing another way. I just want to be sure that, if not all,
> most of people agree on that solution and if possible, it is compliant with
> DT policy so everybody is happy and works together.
> That's why I involve DT people, even if it's a small detail, so they can
> advise us.
>
> Anyway, at some point we have to take a decision to carry on thinks.
> So actually, I would like to avoid a never-ending story :)

Sounds OK to me, I'm not DT expert though ;)

-- 
Rafał