Controller is not getting file submitted

i am submitting the form which is having file but when i try to get the file in controller it always return failure.

i have tried possible thing.

Save

public function storeLogo(request $request){

if($request->hasFile('logo')){

         $image=$request->file($yes);
         $fileName= time().'.'.$image->getClientOriginalExtension();
         $location=public_path('merchantGlobal/'.$fileName);
         Image::make($image)->save($location);
         return "success";

  }

        return "failure";


}

I want get success message of controller

via Chebli Mohamed