SQL & PL/SQL :: Field From Two Tables?

I have two master tables , one is supplier master and the other customer, the requirement is , i will pass a code as IN parameter and the result it should bring the appropriate name of that code , for example if i pass a code which exists in supplier master , it should get me the supplier name for that code , if i pass code which exists in customer ,it should bring customer name.

CREATE TABLE OM_CUST (CUST_CODE VARCHAR2(30),CUST_NAME VARCHAR2(240));
INSERT INTO OM_CUST VALUES ('1001','CUST1');
INSERT INTO OM_CUST VALUES ('1002','CUST2');
CREATE TABLE OM_SUPP (SUPP_CODE VARCHAR2(30),SUPP_NAME VARCHAR2(240));
INSERT INTO OM_SUPP VALUES ('2001','SUPP1');
INSERT INTO OM_SUPP VALUES ('2002','SUPP2');