carl9170: set beacon xmit power to the max

Harshal Chhaya discovered during network tests, that
several of his clients dropped-off the network. The
captured packets shows that the beacons sent by the
AP are at a much lower power than the other data
packets.

The reason for this mishap: The driver never updated
the beacon phy register, so all beacons were always
sent at the lowest power.

Reference: http://marc.info/?l=linux-wireless&m=131067225105801
Reported-by: Harshal Chhaya <harshal@gmail.com>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 108 insertions, 83 deletions

diff --git a/drivers/net/wireless/ath/carl9170/tx.c b/drivers/net/wireless/ath/carl9170/tx.c
index 0f8cdeffd64..d20946939cd 100644
--- a/drivers/net/wireless/ath/carl9170/tx.c
+++ b/drivers/net/wireless/ath/carl9170/tx.c
@@ -661,11 +661,67 @@ void carl9170_tx_process_status(struct ar9170 *ar,
 	}
 }
 
+static void carl9170_tx_rate_tpc_chains(struct ar9170 *ar,
+	struct ieee80211_tx_info *info,	struct ieee80211_tx_rate *txrate,
+	unsigned int *phyrate, unsigned int *tpc, unsigned int *chains)
+{
+	struct ieee80211_rate *rate = NULL;
+	u8 *txpower;
+	unsigned int idx;
+
+	idx = txrate->idx;
+	*tpc = 0;
+	*phyrate = 0;
+
+	if (txrate->flags & IEEE80211_TX_RC_MCS) {
+		if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
+			/* +1 dBm for HT40 */
+			*tpc += 2;
+
+			if (info->band == IEEE80211_BAND_2GHZ)
+				txpower = ar->power_2G_ht40;
+			else
+				txpower = ar->power_5G_ht40;
+		} else {
+			if (info->band == IEEE80211_BAND_2GHZ)
+				txpower = ar->power_2G_ht20;
+			else
+				txpower = ar->power_5G_ht20;
+		}
+
+		*phyrate = txrate->idx;
+		*tpc += txpower[idx & 7];
+	} else {
+		if (info->band == IEEE80211_BAND_2GHZ) {
+			if (idx < 4)
+				txpower = ar->power_2G_cck;
+			else
+				txpower = ar->power_2G_ofdm;
+		} else {
+			txpower = ar->power_5G_leg;
+			idx += 4;
+		}
+
+		rate = &__carl9170_ratetable[idx];
+		*tpc += txpower[(rate->hw_value & 0x30) >> 4];
+		*phyrate = rate->hw_value & 0xf;
+	}
+
+	if (ar->eeprom.tx_mask == 1) {
+		*chains = AR9170_TX_PHY_TXCHAIN_1;
+	} else {
+		if (!(txrate->flags & IEEE80211_TX_RC_MCS) &&
+		    rate && rate->bitrate >= 360)
+			*chains = AR9170_TX_PHY_TXCHAIN_1;
+		else
+			*chains = AR9170_TX_PHY_TXCHAIN_2;
+	}
+}
+
 static __le32 carl9170_tx_physet(struct ar9170 *ar,
 	struct ieee80211_tx_info *info, struct ieee80211_tx_rate *txrate)
 {
-	struct ieee80211_rate *rate = NULL;
-	u32 power, chains;
+	unsigned int power = 0, chains = 0, phyrate = 0;
 	__le32 tmp;
 
 	tmp = cpu_to_le32(0);
@@ -682,35 +738,12 @@ static __le32 carl9170_tx_physet(struct ar9170 *ar,
 		tmp |= cpu_to_le32(AR9170_TX_PHY_SHORT_GI);
 
 	if (txrate->flags & IEEE80211_TX_RC_MCS) {
-		u32 r = txrate->idx;
-		u8 *txpower;
+		SET_VAL(AR9170_TX_PHY_MCS, phyrate, txrate->idx);
 
 		/* heavy clip control */
-		tmp |= cpu_to_le32((r & 0x7) <<
+		tmp |= cpu_to_le32((txrate->idx & 0x7) <<
 			AR9170_TX_PHY_TX_HEAVY_CLIP_S);
 
-		if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
-			if (info->band == IEEE80211_BAND_5GHZ)
-				txpower = ar->power_5G_ht40;
-			else
-				txpower = ar->power_2G_ht40;
-		} else {
-			if (info->band == IEEE80211_BAND_5GHZ)
-				txpower = ar->power_5G_ht20;
-			else
-				txpower = ar->power_2G_ht20;
-		}
-
-		power = txpower[r & 7];
-
-		/* +1 dBm for HT40 */
-		if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
-			power += 2;
-
-		r <<= AR9170_TX_PHY_MCS_S;
-		BUG_ON(r & ~AR9170_TX_PHY_MCS);
-
-		tmp |= cpu_to_le32(r & AR9170_TX_PHY_MCS);
 		tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_HT);
 
 		/*
@@ -720,34 +753,15 @@ static __le32 carl9170_tx_physet(struct ar9170 *ar,
 		 * tmp |= cpu_to_le32(AR9170_TX_PHY_GREENFIELD);
 		 */
 	} else {
-		u8 *txpower;
-		u32 mod;
-		u32 phyrate;
-		u8 idx = txrate->idx;
-
-		if (info->band != IEEE80211_BAND_2GHZ) {
-			idx += 4;
-			txpower = ar->power_5G_leg;
-			mod = AR9170_TX_PHY_MOD_OFDM;
+		if (info->band == IEEE80211_BAND_2GHZ) {
+			if (txrate->idx <= AR9170_TX_PHY_RATE_CCK_11M)
+				tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_CCK);
+			else
+				tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_OFDM);
 		} else {
-			if (idx < 4) {
-				txpower = ar->power_2G_cck;
-				mod = AR9170_TX_PHY_MOD_CCK;
-			} else {
-				mod = AR9170_TX_PHY_MOD_OFDM;
-				txpower = ar->power_2G_ofdm;
-			}
+			tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_OFDM);
 		}
 
-		rate = &__carl9170_ratetable[idx];
-
-		phyrate = rate->hw_value & 0xF;
-		power = txpower[(rate->hw_value & 0x30) >> 4];
-		phyrate <<= AR9170_TX_PHY_MCS_S;
-
-		tmp |= cpu_to_le32(mod);
-		tmp |= cpu_to_le32(phyrate);
-
 		/*
 		 * short preamble seems to be broken too.
 		 *
@@ -755,23 +769,12 @@ static __le32 carl9170_tx_physet(struct ar9170 *ar,
 		 *	tmp |= cpu_to_le32(AR9170_TX_PHY_SHORT_PREAMBLE);
 		 */
 	}
-	power <<= AR9170_TX_PHY_TX_PWR_S;
-	power &= AR9170_TX_PHY_TX_PWR;
-	tmp |= cpu_to_le32(power);
-
-	/* set TX chains */
-	if (ar->eeprom.tx_mask == 1) {
-		chains = AR9170_TX_PHY_TXCHAIN_1;
-	} else {
-		chains = AR9170_TX_PHY_TXCHAIN_2;
-
-		/* >= 36M legacy OFDM - use only one chain */
-		if (rate && rate->bitrate >= 360 &&
-		    !(txrate->flags & IEEE80211_TX_RC_MCS))
-			chains = AR9170_TX_PHY_TXCHAIN_1;
-	}
-	tmp |= cpu_to_le32(chains << AR9170_TX_PHY_TXCHAIN_S);
+	carl9170_tx_rate_tpc_chains(ar, info, txrate,
+				    &phyrate, &power, &chains);
 
+	tmp |= cpu_to_le32(SET_CONSTVAL(AR9170_TX_PHY_MCS, phyrate));
+	tmp |= cpu_to_le32(SET_CONSTVAL(AR9170_TX_PHY_TX_PWR, power));
+	tmp |= cpu_to_le32(SET_CONSTVAL(AR9170_TX_PHY_TXCHAIN, chains));
 	return tmp;
 }
 
@@ -1444,8 +1447,10 @@ int carl9170_update_beacon(struct ar9170 *ar, const bool submit)
 	struct sk_buff *skb = NULL;
 	struct carl9170_vif_info *cvif;
 	struct ieee80211_tx_info *txinfo;
+	struct ieee80211_tx_rate *rate;
 	__le32 *data, *old = NULL;
-	u32 word, off, addr, len;
+	unsigned int plcp, power, chains;
+	u32 word, ht1, off, addr, len;
 	int i = 0, err = 0;
 
 	rcu_read_lock();
@@ -1476,11 +1481,6 @@ found:
 	}
 
 	txinfo = IEEE80211_SKB_CB(skb);
-	if (txinfo->control.rates[0].flags & IEEE80211_TX_RC_MCS) {
-		err = -EINVAL;
-		goto err_free;
-	}
-
 	spin_lock_bh(&ar->beacon_lock);
 	data = (__le32 *)skb->data;
 	if (cvif->beacon)
@@ -1510,18 +1510,43 @@ found:
 		goto err_unlock;
 	}
 
-	i = txinfo->control.rates[0].idx;
-	if (txinfo->band != IEEE80211_BAND_2GHZ)
-		i += 4;
+	ht1 = AR9170_MAC_BCN_HT1_TX_ANT0;
+	rate = &txinfo->control.rates[0];
+	carl9170_tx_rate_tpc_chains(ar, txinfo, rate, &plcp, &power, &chains);
+	if (!(txinfo->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
+		if (plcp <= AR9170_TX_PHY_RATE_CCK_11M)
+			plcp |= ((skb->len + FCS_LEN) << (3 + 16)) + 0x0400;
+		else
+			plcp |= ((skb->len + FCS_LEN) << 16) + 0x0010;
+	} else {
+		ht1 |= AR9170_MAC_BCN_HT1_HT_EN;
+		if (rate->flags & IEEE80211_TX_RC_SHORT_GI)
+			plcp |= AR9170_MAC_BCN_HT2_SGI;
 
-	word = __carl9170_ratetable[i].hw_value & 0xf;
-	if (i < 4)
-		word |= ((skb->len + FCS_LEN) << (3 + 16)) + 0x0400;
-	else
-		word |= ((skb->len + FCS_LEN) << 16) + 0x0010;
+		if (rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
+			ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_SHARED;
+			plcp |= AR9170_MAC_BCN_HT2_BW40;
+		}
+		if (rate->flags & IEEE80211_TX_RC_DUP_DATA) {
+			ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_DUP;
+			plcp |= AR9170_MAC_BCN_HT2_BW40;
+		}
+
+		SET_VAL(AR9170_MAC_BCN_HT2_LEN, plcp, skb->len + FCS_LEN);
+	}
+
+	SET_VAL(AR9170_MAC_BCN_HT1_PWR_CTRL, ht1, 7);
+	SET_VAL(AR9170_MAC_BCN_HT1_TPC, ht1, power);
+	SET_VAL(AR9170_MAC_BCN_HT1_CHAIN_MASK, ht1, chains);
+	if (chains == AR9170_TX_PHY_TXCHAIN_2)
+		ht1 |= AR9170_MAC_BCN_HT1_TX_ANT1;
 
 	carl9170_async_regwrite_begin(ar);
-	carl9170_async_regwrite(AR9170_MAC_REG_BCN_PLCP, word);
+	carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT1, ht1);
+	if (!(txinfo->control.rates[0].flags & IEEE80211_TX_RC_MCS))
+		carl9170_async_regwrite(AR9170_MAC_REG_BCN_PLCP, plcp);
+	else
+		carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT2, plcp);
 
 	for (i = 0; i < DIV_ROUND_UP(skb->len, 4); i++) {
 		/*