Redirect 2 pages back or redirect from where the user came

Question

I have a website, got it developed from someone, Need help in redirecting back after login in php.

After Login it redirects to Home Page. But i want user to go back where he came from.

logincontroller.php

    public function checklogin(Request $request){
        $phone = DB::table('users')->where('contact','=',$request->input('code').$request->input('contact'))->get();
        if(count($phone)>0){
            $user_data = array(
                'email' => $phone[0]->email,
                'password' => $request->get('password')
            );

            if(Auth::attempt($user_data)){
                return redirect('/');
            }else{
                return back()->with('error','wrong_details');
            }
        }else{
            return back()->with('error','wrong_details');
        }
    }