The ISA_BUS_API Kconfig option enables the compilation of the ISA bus driver. The ISA bus driver does not perform any hardware interaction, and is instead just a thin layer of software abstraction to eliminate boilerplate code common to ISA-style device drivers. Since ISA_BUS_API has no dependencies and does not jeopardize the integrity of the system when enabled, drivers should select it when the ISA bus driver functionality is needed. Originally, when the ISA_BUS_API Kconfig option was introduced, it served a dual-purpose of masking drivers ISA-style devices not commonly found for desktop systems, such as the PC/104 device drivers. This secondary semantic was inappropriate for the ISA_BUS_API option, and proper masking of these device drivers is now accomplished via dedicated Kconfig options such as CONFIG_PC104. Linus, please pickup this entire patchset through your GPIO subsystem tree; a recursive dependency error is present if these patches are cherry-picked (see https://lkml.org/lkml/2017/12/26/235), so they should be merged together in the same tree. Maciej, this patchset resolves the recursive dependency issue you encountered, so now you should be able to submit your Winbond GPIO driver with the ISA_BUS_API selection as desired. William Breathitt Gray (3): iio: Change ISA_BUS_API dependency to selection watchdog: Change ISA_BUS_API dependency to selection gpio: Change ISA_BUS_API dependency to selection drivers/gpio/Kconfig | 14 +++++++++----- drivers/iio/adc/Kconfig | 3 ++- drivers/iio/counter/Kconfig | 3 ++- drivers/iio/dac/Kconfig | 3 ++- drivers/watchdog/Kconfig | 3 ++- 5 files changed, 17 insertions(+), 9 deletions(-) -- 2.15.1 -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html