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

[Marek Vasut]

On 01/17/2017 04:49 PM, Rafał Miłecki wrote:
> 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 ;)

So ok, we already have a few non-jedec bindings documented in
jedec,spi-nor,text . Let's just apply this patch and if someone wants to
split the
binding document, patch is welcome. Good ?

-- 
Best regards,
Marek Vasut