From: Matti Vaittinen <matti.vaittinen@xxxxxxxxxxxxxxxxx> [ Upstream commit 41a8e19f47dfe9154c56b35842700ad38a7c33e0 ] With CONFIG_BD70528_WATCHDOG=m, a built-in rtc driver cannot call into the low-level functions that are part of the watchdog module: drivers/rtc/rtc-bd70528.o: In function `bd70528_set_time': rtc-bd70528.c:(.text+0x22c): undefined reference to `bd70528_wdt_lock' rtc-bd70528.c:(.text+0x2a8): undefined reference to `bd70528_wdt_unlock' drivers/rtc/rtc-bd70528.o: In function `bd70528_set_rtc_based_timers': rtc-bd70528.c:(.text+0x50c): undefined reference to `bd70528_wdt_set' Add a Kconfig dependency which forces RTC to be a module if watchdog is a module. If watchdog is not compiled at all the stub functions for watchdog control are used. compiling the RTC without watchdog is fine. Fixes: 32a4a4ebf768 ("rtc: bd70528: Initial support for ROHM bd70528 RTC") Suggested-by: Arnd Bergmann <arnd@xxxxxxxx> Reported-by: kbuild test robot <lkp@xxxxxxxxx> Signed-off-by: Matti Vaittinen <matti.vaittinen@xxxxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/84462e01e43d39024948a3bdd24087ff87dc2255.1565591387.git.matti.vaittinen@xxxxxxxxxxxxxxxxx Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/rtc/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index e72f65b61176d..add43c3374895 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -500,6 +500,7 @@ config RTC_DRV_M41T80_WDT watchdog timer in the ST M41T60 and M41T80 RTC chips series. config RTC_DRV_BD70528 tristate "ROHM BD70528 PMIC RTC" + depends on MFD_ROHM_BD70528 && (BD70528_WATCHDOG || !BD70528_WATCHDOG) help If you say Y here you will get support for the RTC on ROHM BD70528 Power Management IC. -- 2.20.1