ath9k_htc: Add support for bluetooth coexistence.

Signed-off-by: Vivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/btcoex.c b/drivers/net/wireless/ath/ath9k/btcoex.c
index fb4ac15..6a92e57 100644
--- a/drivers/net/wireless/ath/ath9k/btcoex.c
+++ b/drivers/net/wireless/ath/ath9k/btcoex.c
@@ -168,6 +168,7 @@
 static void ath9k_hw_btcoex_enable_3wire(struct ath_hw *ah)
 {
 	struct ath_btcoex_hw *btcoex_hw = &ah->btcoex_hw;
+	u32  val;
 
 	/*
 	 * Program coex mode and weight registers to
@@ -177,6 +178,12 @@
 	REG_WRITE(ah, AR_BT_COEX_WEIGHT, btcoex_hw->bt_coex_weights);
 	REG_WRITE(ah, AR_BT_COEX_MODE2, btcoex_hw->bt_coex_mode2);
 
+	if (AR_SREV_9271(ah)) {
+		val = REG_READ(ah, 0x50040);
+		val &= 0xFFFFFEFF;
+		REG_WRITE(ah, 0x50040, val);
+	}
+
 	REG_RMW_FIELD(ah, AR_QUIET1, AR_QUIET1_QUIET_ACK_CTS_ENABLE, 1);
 	REG_RMW_FIELD(ah, AR_PCU_MISC, AR_PCU_BT_ANT_PREVENT_RX, 0);