Re: [PATCH] mtd: onenand: omap2: add dependency on GPMC

[Roger Quadros <rogerq@kernel.org>]

On 07/11/2022 10:55, Krzysztof Kozlowski wrote:
> On 07/11/2022 09:44, Roger Quadros wrote:
>> Hello Krzysztof,
>>
>> On 04/11/2022 21:49, Krzysztof Kozlowski wrote:
>>> OMAP2 OneNAND driver uses gpmc_omap_onenand_set_timings() provided by
>>> OMAP GPMC driver, so the latter cannot be module if OneNAND driver is
>>> built-in:
>>>
>>>   /usr/bin/arm-linux-gnueabi-ld: drivers/mtd/nand/onenand/onenand_omap2.o: in function `omap2_onenand_probe':
>>>   onenand_omap2.c:(.text+0x520): undefined reference to `gpmc_omap_onenand_set_timings'
>>>
>>> Reported-by: kernel test robot <lkp@intel.com>
>>> Fixes: 854fd9209b20 ("memory: omap-gpmc: Allow building as a module")
>>> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>>> ---
>>>  drivers/mtd/nand/onenand/Kconfig | 1 +
>>>  1 file changed, 1 insertion(+)
>>>
>>> diff --git a/drivers/mtd/nand/onenand/Kconfig b/drivers/mtd/nand/onenand/Kconfig
>>> index 34d9a7a82ad4..fa94c514626d 100644
>>> --- a/drivers/mtd/nand/onenand/Kconfig
>>> +++ b/drivers/mtd/nand/onenand/Kconfig
>>> @@ -26,6 +26,7 @@ config MTD_ONENAND_OMAP2
>>>  	tristate "OneNAND on OMAP2/OMAP3 support"
>>>  	depends on ARCH_OMAP2 || ARCH_OMAP3 || (COMPILE_TEST && ARM)
>>>  	depends on OF || COMPILE_TEST
>>> +	depends on OMAP_GPMC || !OMAP_GPMC
>>
>> Why did you add !OMAP_GPMC?
>>
>> If OMAP_GPMC is not set we don't want to be able to build this driver correct?
> 
> It will build fine because of stubs, so building is not a problem. We
> just want to forbid having this built-in if OMAP_GPMC is a module. The
> question is whether this is a runtime dependency as well?

Yes, there is a runtime dependency. Without the OMAP_GPMC driver
this MTD_ONENAND_OMAP2 will not work.

cheers,
-roger