ath9k_hw: Add functions to get/set antenna diversity configuration

Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/ar9002_phy.h b/drivers/net/wireless/ath/ath9k/ar9002_phy.h
index c5151a4..37663db 100644
--- a/drivers/net/wireless/ath/ath9k/ar9002_phy.h
+++ b/drivers/net/wireless/ath/ath9k/ar9002_phy.h
@@ -302,6 +302,8 @@
 #define AR_PHY_NEW_ADC_DC_OFFSET_CORR_ENABLE 0x80000000
 
 #define AR_PHY_MULTICHAIN_GAIN_CTL          0x99ac
+#define AR_PHY_9285_FAST_DIV_BIAS	    0x00007E00
+#define AR_PHY_9285_FAST_DIV_BIAS_S	    9
 #define AR_PHY_9285_ANT_DIV_CTL_ALL         0x7f000000
 #define AR_PHY_9285_ANT_DIV_CTL             0x01000000
 #define AR_PHY_9285_ANT_DIV_CTL_S           24