code: func (e *Adaptor) AnalogRead(pin string) (val int, err error) {
  	buf, err := e.readFile(
  		"/sys/bus/iio/devices/iio:device1/in_voltage" + pin + "_raw",
  	)
  	if err != nil {
  		return
  	}
  
  	val, err = strconv.Atoi(string(buf[0 : len(buf)-1]))
  
  	return val / 4, err
  }
docs: // AnalogRead returns value from analog reading of specified pin