in EF5 or less, all ok.
in EF6, you need to use mysql connector 6.8.x, and add DbConfigurationTypeAttribute to you DbContext:
[DbConfigurationType(typeof(MySql.Data.Entity.MySqlEFConfiguration))]
public class DemoContext : DbContext{}
which MySqlEFConfiguration is in MySql.Data.Entity.EF6.dll in 6.8.x. Have a try!