Initial commit: get everything rolling

sysfs-functions.js

@@ -0,0 +1,80 @@
+// sysfs functions
+const fs = require('node:fs');
+
+const LED_PATH = fs.existsSync('/sys/class/leds/ACT') 
+    ? '/sys/class/leds/ACT' 
+    : '/sys/class/leds/led0';
+
+// detach kernel trigger once at startup
+try {
+    fs.writeFileSync(`${LED_PATH}/trigger`, 'none');
+} catch (err) {
+    console.error(`[LED] failed to claim sysfs led:`, err.message);
+}
+
+let blinkTimer = null;
+
+function setBrightness(val) {
+    try {
+        fs.writeFileSync(`${LED_PATH}/brightness`, val.toString());
+    } catch (err) {
+        console.error(`[LED] error writing brightness:`, err.message);
+    }
+}
+
+function turnOff() {
+    stopBlink();
+    setBrightness(0);
+}
+
+function turnOn() {
+    stopBlink();
+    setBrightness(1);
+}
+
+function getState() {
+    try {
+        return parseInt(fs.readFileSync(`${LED_PATH}/brightness`, 'utf8').trim(), 10);
+    } catch {
+        return null;
+    }
+}
+
+function toggle() {
+    setBrightness(getState() === 1 ? 0 : 1);
+}
+
+function startBlink(interval = 500) {
+    stopBlink();
+    let state = 1;
+    setBrightness(state);
+
+    blinkTimer = setInterval(() => {
+        state = state === 1 ? 0 : 1;
+        setBrightness(state);
+    }, interval);
+}
+
+function stopBlink() {
+    if (blinkTimer) {
+        clearInterval(blinkTimer);
+        blinkTimer = null;
+    }
+}
+
+function restoreDefault() {
+    stopBlink();
+    try {
+        fs.writeFileSync(`${LED_PATH}/trigger`, 'mmc0');
+    } catch {}
+}
+
+module.exports = {
+    turnOff,
+    turnOn,
+    toggle,
+    getState,
+    startBlink,
+    stopBlink,
+    restoreDefault
+};