rtlwifi: Add encryption argument in rtl_is_special_data for checking DHCP packet.

rtl8192cu can't connect to AP after physical reconnect.
according to dmesg, that problem's cause was DHCP timeout.

rtl_is_special_data function checks packet type for adjusting rate.
when that function is called from _rtl_rc_get_highest_rix, it can not
calculate offset correctly. so i add argument is_encn in rtl_is_special_data.
is_enc variable mean that iv header is added in skb parameter.

i test only rtl8192cu chipset. because i doesn't have other rtlwifi chipsets.
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/rtlwifi/base.c

@@ -1315,7 +1315,8 @@ static void setup_arp_tx(struct rtl_priv *rtlpriv, struct rtl_ps_ctl *ppsc)
 }
 
 /*should call before software enc*/
-u8 rtl_is_special_data(struct ieee80211_hw *hw, struct sk_buff *skb, u8 is_tx)
+u8 rtl_is_special_data(struct ieee80211_hw *hw, struct sk_buff *skb, u8 is_tx,
+		       bool is_enc)
 {
 	struct rtl_priv *rtlpriv = rtl_priv(hw);
 	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));
@@ -1344,7 +1345,9 @@ u8 rtl_is_special_data(struct ieee80211_hw *hw, struct sk_buff *skb, u8 is_tx)
 		break;
 	}
 
-	offset = mac_hdr_len + SNAP_SIZE + encrypt_header_len;
+	offset = mac_hdr_len + SNAP_SIZE;
+	if (is_enc)
+		offset += encrypt_header_len;
 	ether_type = be16_to_cpup((__be16 *)(skb->data + offset));
 
 	if (ETH_P_IP == ether_type) {

drivers/net/wireless/rtlwifi/base.h

@@ -120,7 +120,8 @@ bool rtl_action_proc(struct ieee80211_hw *hw, struct sk_buff *skb, u8 is_tx);
 int rtlwifi_rate_mapping(struct ieee80211_hw *hw, bool isht,
 			 bool isvht, u8 desc_rate);
 bool rtl_tx_mgmt_proc(struct ieee80211_hw *hw, struct sk_buff *skb);
-u8 rtl_is_special_data(struct ieee80211_hw *hw, struct sk_buff *skb, u8 is_tx);
+u8 rtl_is_special_data(struct ieee80211_hw *hw, struct sk_buff *skb, u8 is_tx,
+		       bool is_enc);
 
 void rtl_beacon_statistic(struct ieee80211_hw *hw, struct sk_buff *skb);
 int rtl_tx_agg_start(struct ieee80211_hw *hw, struct ieee80211_vif *vif,

drivers/net/wireless/rtlwifi/pci.c

@@ -887,7 +887,7 @@ static void _rtl_pci_rx_interrupt(struct ieee80211_hw *hw)
 				unicast = true;
 				rtlpriv->stats.rxbytesunicast += skb->len;
 			}
-			rtl_is_special_data(hw, skb, false);
+			rtl_is_special_data(hw, skb, false, true);
 
 			if (ieee80211_is_data(fc)) {
 				rtlpriv->cfg->ops->led_control(hw, LED_CTL_RX);

drivers/net/wireless/rtlwifi/rc.c

@@ -56,7 +56,8 @@ static u8 _rtl_rc_get_highest_rix(struct rtl_priv *rtlpriv,
 		wireless_mode = sta_entry->wireless_mode;
 	}
 
-	if (rtl_is_special_data(rtlpriv->mac80211.hw, skb, true) || not_data) {
+	if (rtl_is_special_data(rtlpriv->mac80211.hw, skb, true, false) ||
+	    not_data) {
 		return 0;
 	} else {
 		if (rtlhal->current_bandtype == BAND_ON_2_4G) {
@@ -201,7 +202,7 @@ static void rtl_tx_status(void *ppriv,
 	if (!priv_sta || !ieee80211_is_data(fc))
 		return;
 
-	if (rtl_is_special_data(mac->hw, skb, true))
+	if (rtl_is_special_data(mac->hw, skb, true, true))
 		return;
 
 	if (is_multicast_ether_addr(ieee80211_get_DA(hdr)) ||