[PATCH] Documentation: dt: mtd: replace "nor-jedec" binding with "jedec, spi-nor"

Rafał Miłecki zajec5 at gmail.com
Thu May 21 01:01:05 PDT 2015

On 21 May 2015 at 09:25, Brian Norris <computersforpeace at gmail.com> wrote:
> (trim CC a bit, as this is no longer a DT binding question)
> On Thu, May 21, 2015 at 09:12:25AM +0200, Rafał Miłecki wrote:
>> On 20 May 2015 at 23:35, Brian Norris <computersforpeace at gmail.com> wrote:
>> > On Tue, May 19, 2015 at 09:27:50AM +0200, Rafał Miłecki wrote:
>> >> On 19 May 2015 at 03:34, Brian Norris <computersforpeace at gmail.com> wrote:
>> >> > So how about the following patch? It seems like we'll need to be able to
>> >> > ignore useless 'modalias' values in cases like this:
>> >> >
>> >> >         // modalias = "shinynewdevice"
>> >> >         compatible = "myvendor,shinynewdevice", "jedec,spi-nor";
>> >> >
>> >> > and also if somebody leaves off the entire shinynewdevice string:
>> >> >
>> >> >         // modalias = "spi-nor"
>> >> >         compatible = "jedec,spi-nor";
>> >> >
>> >> > So we rework the spi-nor library to not reject "bad" names, and just
>> >> > fall back to autodetection, and we add the .of_match_table to properly
>> >> > catch all "jedec,spi-nor".
>> >>
>> >> That's nice but what about platforms using platform data instead of
>> >> DT? I would like to use some kind of "spi-nor" (with some prefix
>> >> *maybe*) for them too.
>> >
>> > For platform devices, you might as well just use the name of the driver,
>> > which is 'm25p80'. Isn't that how most platform devices are matched with
>> > drivers?
>> Yes and I think it's ugly because it keeps causing the warning about
>> read flash model not matching specified one (m25p80).
> Sure, I agree.
>> Are you
>> seriously not going to allow platform stuff *clearly* request flash
>> model detection (JEDEC RDID OP)? Just because they don't use DT?
> No, this isn't about "allowing" anything. It's just that my primary
> concern was to get the DT binding straightened out properly. Linus'
> current tree now has the proper binding, but the m25p80.c code doesn't
> quite bind properly. It will work if "jedec,spi-nor" is the first
> entry in the compatible property (and so it becomes the 'modalias', but
> not second, third, etc. So my patch fixes that properly.
> Now, the secondary concern is that you want platform devices to specify
> something generic, and that doesn't yield a "found X, expected Y"
> message. I'm perfectly fine with fixing that too, if you have a patch
> for it. What do you propose?

Maybe I wasn't clear enough. I was going to start using struct
flash_platform_data with
.type = "spi-nor",
but your proposed patch removes support for such name.

While I like matching DT *clearly* against the whole "jedec,spi-nor"
string (really, I'm all for it), I'm confused what I should use for
platform stuff now. I don't have any proposal as my initial plan was
exactly to use this "spi-nor".
I guess I don't want to re-add support for "spi-nor" (as you just
proposed to remove it), so I think I have to bounce the question: what
alternative do you propose?


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