stack-chan

import AXP2101 from "embedded:peripheral/Power/axp2101";
import baseSetup from "m5stack-cores3/setup-target";

// Mirrors the CoreS3 power-rail setup used by M5Stack/StackChan firmware
// (`firmware/main/hal/board/stackchan.cc` near the AXP2101 init path) and the
// X-Powers AXP2101 register map for DCDC/ALDO/BLDO/LDO and charge-control fields.
function patchStackChanPower() {
	const axp2101 = new AXP2101({
		address: 0x34,
		sensor: { ...device.I2C.internal, io: device.io.SMBus },
	});

	const data = axp2101.readByte(0x90);
	// Enable the LDO rails needed by the CoreS3 StackChan base.
	axp2101.writeByte(0x90, data | 0b10110100);
	// Set DCDC/LDO voltage selector used by the reference firmware.
	axp2101.writeByte(0x97, 0b11110 - 2);
	// Configure VBUS input current limit and power-path behavior.
	axp2101.writeByte(0x69, 0b00110101);
	// Enable required DCDC outputs.
	axp2101.writeByte(0x30, 0b111111);
	// Force the final LDO enable mask after the voltage selectors are set.
	axp2101.writeByte(0x90, 0xbf);
	// Set ALDO/BLDO voltage setpoints.
	axp2101.writeByte(0x94, 33 - 5);
	axp2101.writeByte(0x95, 33 - 5);
	// Disable one unused LDO path to match the reference board profile.
	axp2101.writeByte(0x27, 0x00);

	const charge = axp2101.readByte(0x62);
	// Preserve charge-control upper bits and set the target charge-current field.
	axp2101.writeByte(0x62, (charge & 0xe0) | 13);
	trace("[m5stackchan] patched CoreS3 AXP2101 power rails\n");
}

export default function (done) {
	baseSetup(() => {
		try {
			patchStackChanPower();
		} catch (error) {
			trace(`[m5stackchan] AXP2101 power patch failed: ${error}\n`);
		}
		done?.();
	});
}