Re: [PATCH] drivers: Let several drivers depends on HAS_IOMEM for 'devm_ioremap_resource'

Richard Weinberger
2014-07-18T10:51:10Z

Am 18.07.2014 12:44, schrieb Chen Gang:
> On 07/18/2014 03:35 PM, Richard Weinberger wrote:
>> Am 18.07.2014 02:36, schrieb Chen Gang:
>>>
>>> On 07/18/2014 02:09 AM, Richard Weinberger wrote:
>>>> Am 17.07.2014 12:48, schrieb Arnd Bergmann:
>>>>> AFAICT, NO_IOMEM only has a real purpose on UML these days. Could we take
>>>>> a shortcut here and make COMPILE_TEST depend on !UML? Getting random stuff
>>>>> to build on UML seems pointless to me and we special-case it in a number of
>>>>> places already.
>>>>
>>>> If UML is the only arch without io memory the dependency on !UML seems
>>>> reasonable to me. :-)
>>>>
>>>
>>> For me, if only uml left, I suggest to implement dummy functions within
>>> uml instead of let CONFIG_UML appear in generic include directory. And
>>> then remove all HAS_IOMEM and NO_IOMEM from kernel.
>>
>> Erm, this is something completely different.
>> I thought we're focusing on COMPILE_TEST?
>>
>
> COMPILE_TEST is none-architecture specific, but UML is. So in generic
> include folder, if we're focusing on choosing whether COMPILE_TEST or
> UML, for me, I will choose COMPILE_TEST.
>
> If we're not only focusing on COMPILE_TEST, for me, if something only
> depend on one architecture, I'd like to put them under "arch/*/" folder.
>
> Especially, after that, we can remove all HAS_IOMEM and NO_IOMEM, nobody
> has to think of them again. :-)

And then we end up with a solution that on UML a lot of completely useless
drivers are build which fail in various interesting manners because you'll
add stubs for all kinds of io memory related functions to arch/um/?
We had this kind of discussion already. You'll need more than ioremap...

I like Arnd's idea *much* more to make COMPILE_TEST depend on !UML.

Thanks,
//richard