Re: [PATCH] Documentation: dt: mtd: replace "nor-jedec" binding with "jedec,spi-nor"
From: RafaÅ MiÅecki
Date: Thu May 21 2015 - 05:47:20 EST
On 21 May 2015 at 11:39, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
> On Thu, May 21, 2015 at 11:31 AM, RafaÅ MiÅecki <zajec5@xxxxxxxxx> wrote:
>> On 21 May 2015 at 10:58, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
>>> On Thu, May 21, 2015 at 10:50 AM, RafaÅ MiÅecki <zajec5@xxxxxxxxx> wrote:
>>>>>>> I think your comments suggest that I shouldn't be removing "spi-nor"
>>>>>>> from m25p_ids[] nor from this block:
>>>>>>>
>>>>>>> if (data && data->type)
>>>>>>> flash_name = data->type;
>>>>>>> else if (!strcmp(spi->modalias, "spi-nor"))
>>>>>>> flash_name = NULL; /* auto-detect */
>>>>>>> else
>>>>>>> flash_name = spi->modalias;
>>>>>>>
>>>>>>> So it stays in both m25p_ids[] and .of_match_table.
>>>>>>>
>>>>>>> I suppose that can work. It then allows people to do weird stuff like:
>>>>>>>
>>>>>>> compatible = "idontknowwhatimdoing,spi-nor";
>>>>>>>
>>>>>>> in their device tree. But other than that, there's not much downside I don't
>>>>>>> think.
>>>>>>
>>>>>> It sounds like a reasonable solution. I guess there isn't a perfect
>>>>>> one. Even if we decide to go for sth like "jedec-spi-nor", there
>>>>>> always will be a chance of someone using
>>>>>> compatible = "idontknowwhatimdoing,jedec-spi-nor";
>>>>>> So if you rework your patch to leave "spi-nor" support in m25p_ids and
>>>>>> conditions block, it should be OK.
>>>>>
>>>>> Typically platform devices just use the driver's name. Hence IMHO there's
>>>>> no need to add a shiny new spi-nor device name.
>>>>>
>>>>> So what's wrong with using "m25p80", and treating that as auto-detect iff
>>>>> !spi->dev.of_node?
>>>>
>>>> Treating "m25p80" as auto-detect triggering string won't allow
>>>> platform to *force* "m25p80" flash type if there ever appears to be
>>>> needed. Maybe it's unlikely, but it still sounds like a bit bad design
>>>> for me.
>>>
>>> To force m25p80 flash, you set flash_platform_data.type to "m25p80"?
>>
>> Oh, I think I got lost in the way m25p80 is probed. Is it handled by
>> spi_board_info and its "modalias"?
>
> Indeed.
>
>> Could I leave flash_platform_data.type set to NULL and still have m25p80 probed?
>
> Yes, that case is the final "else" branch above.
Oh, I feel silly now. So I guess Brian's original patch was correct :|
--
RafaÅ
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