ret = speedtch_read_status(instance);
        if (ret < 0) {
                atm_warn(usbatm, "error %d fetching device status\n", ret);
-               if (instance->poll_delay < MAX_POLL_DELAY)
-                       instance->poll_delay *= 2;
+               instance->poll_delay = min(2 * instance->poll_delay, MAX_POLL_DELAY);
                return;
        }
 
-       if (instance->poll_delay > MIN_POLL_DELAY)
-               instance->poll_delay /= 2;
+       instance->poll_delay = max(instance->poll_delay / 2, MIN_POLL_DELAY);
 
        atm_dbg(usbatm, "%s: line state %02x\n", __func__, buf[OFFSET_7]);