ath9k: Add concurrent WLAN and BT tx support for MCI based chips

This feature enables both WLAN and BT can transmit simultaneously
by setting WLAN and BT to equal priorities. Whenever both are
transmitting, it might violate regulatory power limits. To avoid
regulatory violation, WLAN tx power will be adjusted according to BT
power index based on avaliability of BT scheduling message. If the
combined power exceeds threshold, BT transmission will be held off.

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 44 insertions, 16 deletions

diff --git a/drivers/net/wireless/ath/ath9k/btcoex.c b/drivers/net/wireless/ath/ath9k/btcoex.c
index 419e9a3f2fed..05d9be5be52e 100644
--- a/drivers/net/wireless/ath/ath9k/btcoex.c
+++ b/drivers/net/wireless/ath/ath9k/btcoex.c
@@ -218,27 +218,45 @@ void ath9k_hw_btcoex_set_weight(struct ath_hw *ah,
 				enum ath_stomp_type stomp_type)
 {
 	struct ath_btcoex_hw *btcoex_hw = &ah->btcoex_hw;
+	struct ath9k_hw_mci *mci_hw = &ah->btcoex_hw.mci;
+	u8 txprio_shift[] = { 24, 16, 16, 0 }; /* tx priority weight */
+	bool concur_tx = (mci_hw->concur_tx && btcoex_hw->tx_prio[stomp_type]);
+	const u32 *weight = ar9003_wlan_weights[stomp_type];
+	int i;
 
-	if (AR_SREV_9300_20_OR_LATER(ah)) {
-		const u32 *weight = ar9003_wlan_weights[stomp_type];
-		int i;
-
-		if (AR_SREV_9462(ah) || AR_SREV_9565(ah)) {
-			if ((stomp_type == ATH_BTCOEX_STOMP_LOW) &&
-			    btcoex_hw->mci.stomp_ftp)
-				stomp_type = ATH_BTCOEX_STOMP_LOW_FTP;
-			weight = mci_wlan_weights[stomp_type];
-		}
-
-		for (i = 0; i < AR9300_NUM_WLAN_WEIGHTS; i++) {
-			btcoex_hw->bt_weight[i] = AR9300_BT_WGHT;
-			btcoex_hw->wlan_weight[i] = weight[i];
-		}
-	} else {
+	if (!AR_SREV_9300_20_OR_LATER(ah)) {
 		btcoex_hw->bt_coex_weights =
 			SM(bt_weight, AR_BTCOEX_BT_WGHT) |
 			SM(wlan_weight, AR_BTCOEX_WL_WGHT);
+		return;
+	}
+
+	if (AR_SREV_9462(ah) || AR_SREV_9565(ah)) {
+		enum ath_stomp_type stype =
+			((stomp_type == ATH_BTCOEX_STOMP_LOW) &&
+			 btcoex_hw->mci.stomp_ftp) ?
+			ATH_BTCOEX_STOMP_LOW_FTP : stomp_type;
+		weight = mci_wlan_weights[stype];
 	}
+
+	for (i = 0; i < AR9300_NUM_WLAN_WEIGHTS; i++) {
+		btcoex_hw->bt_weight[i] = AR9300_BT_WGHT;
+		btcoex_hw->wlan_weight[i] = weight[i];
+		if (concur_tx && i) {
+			btcoex_hw->wlan_weight[i] &=
+				~(0xff << txprio_shift[i-1]);
+			btcoex_hw->wlan_weight[i] |=
+				(btcoex_hw->tx_prio[stomp_type] <<
+				 txprio_shift[i-1]);
+		}
+	}
+	/* Last WLAN weight has to be adjusted wrt tx priority */
+	if (concur_tx) {
+		btcoex_hw->wlan_weight[i-1] &= ~(0xff << txprio_shift[i-1]);
+		btcoex_hw->wlan_weight[i-1] |= (btcoex_hw->tx_prio[stomp_type]
+						      << txprio_shift[i-1]);
+	}
+
 }
 EXPORT_SYMBOL(ath9k_hw_btcoex_set_weight);
 
@@ -385,3 +403,13 @@ void ath9k_hw_btcoex_bt_stomp(struct ath_hw *ah,
 	}
 }
 EXPORT_SYMBOL(ath9k_hw_btcoex_bt_stomp);
+
+void ath9k_hw_btcoex_set_concur_txprio(struct ath_hw *ah, u8 *stomp_txprio)
+{
+	struct ath_btcoex_hw *btcoex = &ah->btcoex_hw;
+	int i;
+
+	for (i = 0; i < ATH_BTCOEX_STOMP_MAX; i++)
+		btcoex->tx_prio[i] = stomp_txprio[i];
+}
+EXPORT_SYMBOL(ath9k_hw_btcoex_set_concur_txprio);