code: func (p *PWMPin) Period() (period uint32, err error) {
  	buf, err := p.read(p.pwmPeriodPath())
  	if err != nil {
  		return
  	}
  	if len(buf) == 0 {
  		return 0, nil
  	}
  
  	v := bytes.TrimRight(buf, "\n")
  	val, e := strconv.Atoi(string(v))
  	return uint32(val), e
  }
docs: // Period reads from pwm period path and returns value in nanoseconds