BWI_RF_2GHZ_CHAN
CSR_WRITE_2(sc, BWI_RF_CHAN, BWI_RF_2GHZ_CHAN(chan));
CSR_WRITE_2(sc, BWI_RF_CHAN, BWI_RF_2GHZ_CHAN(chan + 4));
CSR_WRITE_2(sc, BWI_RF_CHAN, BWI_RF_2GHZ_CHAN(1));
CSR_WRITE_2(sc, BWI_RF_CHAN, BWI_RF_2GHZ_CHAN(chan));