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 0f8cdeffd645..d20946939cd8 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++) {
                 /*