On Wed, Dec 27, 2017 at 1:24 AM, William Breathitt Gray <vilhelm.g...@gmail.com> wrote:
> Here are the error messages printed on my system when I add a select > ISA_BUS_API line to the GPIO_WINBOND Kconfig option in the version 2 of > your patch: > > drivers/gpio/Kconfig:13:error: recursive dependency detected! > For a resolution refer to Documentation/kbuild/kconfig-language.txt > subsection "Kconfig recursive dependency limitations" > drivers/gpio/Kconfig:13: symbol GPIOLIB is selected by STX104 > For a resolution refer to Documentation/kbuild/kconfig-language.txt > subsection "Kconfig recursive dependency limitations" > drivers/iio/adc/Kconfig:659: symbol STX104 depends on ISA_BUS_API > For a resolution refer to Documentation/kbuild/kconfig-language.txt > subsection "Kconfig recursive dependency limitations" > arch/Kconfig:818: symbol ISA_BUS_API is selected by GPIO_WINBOND > For a resolution refer to Documentation/kbuild/kconfig-language.txt > subsection "Kconfig recursive dependency limitations" > drivers/gpio/Kconfig:701: symbol GPIO_WINBOND depends on GPIOLIB So STX104 depends on ISA_BUS_API which in turn is selected by GPIO_WINBOND which also depends on GPIOLIB. > The issue seems to relate to the select GPIOLIB line for the STX104 > Kconfig option (which has a ISA_BUS_API dependency). Switching GPIOLIB > to be a dependency, or alternatively selecting ISA_BUS_API, alleviates > the recursion. > > Linus, is my use of select GPIOLIB for the STX104 Kconfig option > appropriate in this context -- or should it instead be part of the > depends on line? The STX104 driver includes linux/gpio/driver.h and > makes use of the devm_gpiochip_add_data function to add support for some > minor auxililary GPIO lines on the STX104 device. In the STX104 case, it seems to be appropriate to select GPIOLIB, as it is a GPIO provider, not consumer. Usually I prefer that drivers just select what they need so I don't have to run around in the whole kernel tree and turn things on to the left and right before I can finally select my driver, but maybe that is just me. The other ISA GPIO drivers depends on ISA_BUS_API, I guess in difference from the symbol GPIOLIB it cannot be universally selected, so shouldn't this driver also just depends on ISA_BUS_API and select it from the machine or wherever? Yours, Linus Walleij
