Read Only Access Except Stored Procedures in Specific Schema
If you are looking to create embedded sql-inline Linq queries within Entity Framework, you can assign dbreader or dbwriter permissions appropriately to the application login.

Unfortunately currently in SQL Server, you cannot create specific access to Stored Procedures which only conduct read operations as a category. You will have to grant individual reader or write access to the specific stored procedures by 
Grant execute on Stored procedure to user, etc.