Golang：中断有时间的无限轮询。睡眠

I am using the following simple polling mechanism:

    func poll() {

        for {
            if a {
                device1()
                time.Sleep(time.Second * 10)
            } else {
                sensor1()
                time.Sleep(time.Second * 10)
            }
        }
    }

I need to poll the device1 only if "a" is true otherwise poll the sensor1. Now here "a" will be set to true by clicking the button on UI which will be a random act.

But because of time.Sleep, delay get introduced while checking the condition.

Is there any way to immediately stop time.Sleep when I get the value for "a"? what are the possible ways to implement such interrupts while polling in golang?