Rajinikanth starrer ‘Petta’ film’s promotions have started in full swing. The makers are releasing the characters posters from the film and they have just released the poster of Nawazuddin Siddqui’s character, who will be seen as Singaar Singh in Petta. Director Karthik Subbaraj, in ‘Petta’ Rajinikanth is rumoured to be playing a professor with a violent past.