leds-st1202 requires the LED Pattern Trigger (LEDS_TRIGGER_PATTERN), which is not selected when LED Trigger support is (LEDS_TRIGGERS). To reproduce this: - make menuconfig KCONFIG_CONFIG= - select LEDS_ST1202 dependencies OF, I2C and LEDS_CLASS. - select LEDS_ST1202 - LEDS_TRIGGERS is selected but LEDS_TRIGGER_PATTERN isn't. The absence of LEDS_TRIGGER_PATTERN explicitly required can lead to builds in which LEDS_ST1202 is selected while LEDS_TRIGGER_PATTERN isn't. The direct result of that would be that /sys/class/leds/<led>/hw_pattern wouldn't be available and there would be no way of interacting with the driver and hardware from user space. Add select LEDS_TRIGGER_PATTERN to Kconfig to meet the requirement and indirectly document it as well. Signed-off-by: Manuel Fombuena <fombuena@xxxxxxxxxxx> --- drivers/leds/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 2b27d043921c..8859e8fe292a 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -971,6 +971,7 @@ config LEDS_ST1202 depends on I2C depends on OF select LEDS_TRIGGERS + select LEDS_TRIGGER_PATTERN help Say Y to enable support for LEDs connected to LED1202 LED driver chips accessed via the I2C bus. -- 2.48.1