config文件

CONFIG_LEDS_TRIGGER_TIMER=y
CONFIG_LEDS_GPIO=y

DTS

led1 {
label = "psst:led:button1";
linux,default-trigger = "timer";
gpios = <&pio 4 7 GPIO_ACTIVE_LOW>; // PE7
retain-state-suspended;
};

我想实现自定义的闪烁，心跳闪烁时间似乎不能自定义，我找了网上的帖子，用echo timer不行

echo timer > /sys/class/leds/psst:led:button1/trigger

sh: write error: Invalid argument

cat /sys/class/leds/psst:led:button1/trigger

[none] kbd-scrolllock kbd-numlock kbd-capslock kbd-kanalock kbd-shiftlock kbd-altgrlock kbd-ctrllock kbd-altlock kbd-shiftllock kbd-shiftrlock kbd-ctrlllock kbd-ctrlrlock mmc0 mmc1 heartbeat default-on

发现没有timer这个参数，另外网上说的delay_on delay_off也没有，我要如何让灯闪起来呢？