Re: [PATCH] drivers/memory/Kconfig: Add CONFIG_OF dependency

[Arnd Bergmann]

On Sun, Jul 22, 2018 at 8:29 AM, Boris Brezillon
<boris.brezillon@xxxxxxxxxxx> wrote:
> +Arnd, Rob and the DT ML.
>
> On Sat, 21 Jul 2018 14:53:47 -0700
> Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote:
>
>> On 07/21/2018 01:00 PM, Anders Roxell wrote:
>> > JZ4780_NEMC doesn't depend on OF, and if OF isn't enabled we get this
>> > error:
>> > drivers/memory/jz4780-nemc.c: In function âjz4780_nemc_num_banksâ:
>> > drivers/memory/jz4780-nemc.c:72:10: error: implicit declaration of
>> >  function âof_read_numberâ; did you mean âdown_read_nestedâ?
>> >  [-Werror=implicit-function-declaration]
>> >    bank = of_read_number(prop, 1);
>> >           ^~~~~~~~~~~~~~
>> >           down_read_nested
>
> Looks like of.h defines stubs so that people can compile-test without
> CONFIG_OF selected. Maybe we should move of_read_number() and
> of_read_ulong() out of the #ifdef CONFIG_OF section.

That seems fine, though the added dependency seems appropriate
here as well. of_read_number() is rarely used, and for the most part in
powerpc specific code that is guaranteed to have CONFIG_OF enabled,
so it's not that likely to cause many more problems.

> Alternatively, we could patch jz4780-nemc.c to not use of_read_number
> and instead rely on of_read_property_u32_index() +
> of_property_count_elems_of_size() + of_n_{addr,size}_cells():

That seems noticeably longer for no good reason, I'd go with either
the header file change you suggested or Anders' patch.

       Arnd