Hi there,

I've been having the same problem as yourself today, I've written the below code to solve the problem, its pretty inefficiency but until there is a better way ...

So if you want to tell which joystick is being used you could manipulate this code to detect the other joystick input and add more states ...

using UnityEngine;
using System.Collections;

public class InputControl : MonoBehaviour 
{
    //*********************//
    // Public member data  //
    //*********************//


    //*********************//
    // Private member data //
    //*********************//

    public enum eInputState
    {
        MouseKeyboard,
        Controler
    };
    private eInputState m_State = eInputState.MouseKeyboard;

    //*************************//
    // Unity member methods    //
    //*************************//

    void OnGUI()
    {
        switch( m_State )
        {
            case eInputState.MouseKeyboard:
                if(isControlerInput())
                {
                    m_State = eInputState.Controler;
                    Debug.Log("DREAM - JoyStick being used");
                }
                break;
            case eInputState.Controler:
                if (isMouseKeyboard())
                {
                    m_State = eInputState.MouseKeyboard;
                    Debug.Log("DREAM - Mouse & Keyboard being used");
                }
                break;
        }
    }

    //***************************//
    // Public member methods     //
    //***************************//

    public eInputState GetInputState()
    {
        return m_State;
    }

    //****************************//
    // Private member methods     //
    //****************************//

    private bool isMouseKeyboard()
    {
        // mouse & keyboard buttons
        if (Event.current.isKey ||
            Event.current.isMouse)
        {
            return true;
        }
        // mouse movement
        if( Input.GetAxis("Mouse X") != 0.0f ||
            Input.GetAxis("Mouse Y") != 0.0f )
        {
            return true;
        }
        return false;
    }

    private bool isControlerInput()
    {
        // joystick buttons
        if(Input.GetKey(KeyCode.Joystick1Button0)  ||
           Input.GetKey(KeyCode.Joystick1Button1)  ||
           Input.GetKey(KeyCode.Joystick1Button2)  ||
           Input.GetKey(KeyCode.Joystick1Button3)  ||
           Input.GetKey(KeyCode.Joystick1Button4)  ||
           Input.GetKey(KeyCode.Joystick1Button5)  ||
           Input.GetKey(KeyCode.Joystick1Button6)  ||
           Input.GetKey(KeyCode.Joystick1Button7)  ||
           Input.GetKey(KeyCode.Joystick1Button8)  ||
           Input.GetKey(KeyCode.Joystick1Button9)  ||
           Input.GetKey(KeyCode.Joystick1Button10) ||
           Input.GetKey(KeyCode.Joystick1Button11) ||
           Input.GetKey(KeyCode.Joystick1Button12) ||
           Input.GetKey(KeyCode.Joystick1Button13) ||
           Input.GetKey(KeyCode.Joystick1Button14) ||
           Input.GetKey(KeyCode.Joystick1Button15) ||
           Input.GetKey(KeyCode.Joystick1Button16) ||
           Input.GetKey(KeyCode.Joystick1Button17) ||
           Input.GetKey(KeyCode.Joystick1Button18) ||
           Input.GetKey(KeyCode.Joystick1Button19) )
        {
            return true;
        }

        // joystick axis
        if(Input.GetAxis("XC Left Stick X") != 0.0f ||
           Input.GetAxis("XC Left Stick Y") != 0.0f ||
           Input.GetAxis("XC Triggers") != 0.0f ||
           Input.GetAxis("XC Right Stick X") != 0.0f ||
           Input.GetAxis("XC Right Stick Y") != 0.0f )
        {
            return true;
        }

        return false;
    }
}