From: Arnd Bergmann <arnd@xxxxxxxx> The acpi_processor_ffh_lpi_* functions are defined whenever CONFIG_ACPI is enabled, but only called and declared when CONFIG_ACPI_PROCESSOR_IDLE is also enabled. Without that, a W=1 build triggers missing-prototope warnings, so the #ifdef needs to be adapted: arch/arm64/kernel/cpuidle.c:60:5: error: no previous prototype for 'acpi_processor_ffh_lpi_probe' [-Werror=missing-prototypes] arch/arm64/kernel/cpuidle.c:65:15: error: no previous prototype for 'acpi_processor_ffh_lpi_enter' [-Werror=missing-prototypes] Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> --- arch/arm64/kernel/cpuidle.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kernel/cpuidle.c b/arch/arm64/kernel/cpuidle.c index 42e19fff40ee..d1f68599c29f 100644 --- a/arch/arm64/kernel/cpuidle.c +++ b/arch/arm64/kernel/cpuidle.c @@ -13,7 +13,7 @@ #include <linux/of_device.h> #include <linux/psci.h> -#ifdef CONFIG_ACPI +#ifdef CONFIG_ACPI_PROCESSOR_IDLE #include <acpi/processor.h> -- 2.39.2