Auto scrolling form on keyboard popup

Hi all,
I have created a login page. In a portrait view in screen like tab it works fine but in small screen or landscape mode, there is an issue. If i tap on input field keyboard will pop up but form field is getting scrolled to upper position automatically after some times. the behavior i need is, it should get scrolled up at instance i tap on the input filed.
Is there any to way to get that solve this problem?