We　revise　the　non-Gaussianity　of　canonical　curvaton　scenario　with　a　generalized　delta　N　formalism,　in　which　it　can　handle　the　generic　potentials.　In　various　curvaton　models,　the　energy　density　is　dominant　in　different　periods　including　the　secondary　inflation　of　curvaton,　matter　domination,　and　radiation　domination.　Our　method　can　unify　to　deal　with　these　periods　since　the　nonlinearity　parameter　f(NL)　associated　with　non-Gaussianity　is　a　function　of　equation　of　state　w.　We　first　investigate　the　most　simple　curvaton　scenario,　namely,　the　chaotic　curvaton　with　quadratic　potential.　Our　study　shows　that　most　parameter　spaces　are　satisfied　with　observational　constraints.　And　our　formula　will　nicely　recover　the　well-known　value　of　the　f(NL)　parameter　in　the　absence　of　nonlinear　evolution.　From　the　micro-origin　of　curvaton,　we　also　investigate　the　pseudo-Nambu-Goldstone　curvaton.　Our　result　clearly　indicates　that　the　second　short　inflationary　process　for　pseudo-Nambu-Goldstone　curvaton　is　ruled　out　in　light　of　these　observations.　Finally,　our　method　sheds　a　new　way　of　investigating　the　non-Gaussianity　of　curvaton　mechanism,　especially　for　exploring　the　non-Gaussianity　in　minimal　supersymmetric　Standard　Model　curvaton　model.