case within select mysql

Following the migration of SYBASE to MySQL I have found the following case, a case within the select. I leave the example in case you could guide me how to do it. Thank you!!

select mvfg_cantidad * case mvfg_tipo_origen when 'P' then 1 else -1 end  w_mov   
          from mvfg_mvto_fungibles
         where mvfg_marca = p_marca and mvfg_modelo = p_modelo and mvfg_fecha >= p_fecha and
               ( ( mvfg_tipo_origen = 'P' and mvfg_origen = p_destino) or
                 ( mvfg_tipo_destino = 'P' and mvfg_destino = p_destino)) 
         order by mvfg_fecha desc;