As default setup,
LED current sunk: 0x01, ~10cm stable detection
LED current sunk: 0x0F, ~30cm+ stable detection
...
write_reg(HW_KEY, 0x17);
//0x0F:30cm detection, 0x01:10cm dectection
write_reg(PS_LED21,0xFF);
write_reg(PS_LED3, 0x0F);
//Enable AUX as well
param_set(CHLIST,0b01010111);
...
