File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/net/wireless/ath/wcn36xx/txrx.c b/drivers/net/wireless/ath/wcn36xx/txrx.c
new file mode 100644
index 0000000..9bec823
--- /dev/null
+++ b/drivers/net/wireless/ath/wcn36xx/txrx.c
@@ -0,0 +1,330 @@
+/*
+ * Copyright (c) 2013 Eugene Krasnikov <k.eugene.e@gmail.com>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include "txrx.h"
+
+static inline int get_rssi0(struct wcn36xx_rx_bd *bd)
+{
+	return 100 - ((bd->phy_stat0 >> 24) & 0xff);
+}
+
+int wcn36xx_rx_skb(struct wcn36xx *wcn, struct sk_buff *skb)
+{
+	struct ieee80211_rx_status status;
+	struct ieee80211_hdr *hdr;
+	struct wcn36xx_rx_bd *bd;
+	u16 fc, sn;
+
+	/*
+	 * All fields must be 0, otherwise it can lead to
+	 * unexpected consequences.
+	 */
+	memset(&status, 0, sizeof(status));
+
+	bd = (struct wcn36xx_rx_bd *)skb->data;
+	buff_to_be((u32 *)bd, sizeof(*bd)/sizeof(u32));
+	wcn36xx_dbg_dump(WCN36XX_DBG_RX_DUMP,
+			 "BD   <<< ", (char *)bd,
+			 sizeof(struct wcn36xx_rx_bd));
+
+	skb_put(skb, bd->pdu.mpdu_header_off + bd->pdu.mpdu_len);
+	skb_pull(skb, bd->pdu.mpdu_header_off);
+
+	status.mactime = 10;
+	status.freq = WCN36XX_CENTER_FREQ(wcn);
+	status.band = WCN36XX_BAND(wcn);
+	status.signal = -get_rssi0(bd);
+	status.antenna = 1;
+	status.rate_idx = 1;
+	status.flag = 0;
+	status.rx_flags = 0;
+	status.flag |= RX_FLAG_IV_STRIPPED |
+		       RX_FLAG_MMIC_STRIPPED |
+		       RX_FLAG_DECRYPTED;
+
+	wcn36xx_dbg(WCN36XX_DBG_RX, "status.flags=%x\n", status.flag);
+
+	memcpy(IEEE80211_SKB_RXCB(skb), &status, sizeof(status));
+
+	hdr = (struct ieee80211_hdr *) skb->data;
+	fc = __le16_to_cpu(hdr->frame_control);
+	sn = IEEE80211_SEQ_TO_SN(__le16_to_cpu(hdr->seq_ctrl));
+
+	if (ieee80211_is_beacon(hdr->frame_control)) {
+		wcn36xx_dbg(WCN36XX_DBG_BEACON, "beacon skb %p len %d fc %04x sn %d\n",
+			    skb, skb->len, fc, sn);
+		wcn36xx_dbg_dump(WCN36XX_DBG_BEACON_DUMP, "SKB <<< ",
+				 (char *)skb->data, skb->len);
+	} else {
+		wcn36xx_dbg(WCN36XX_DBG_RX, "rx skb %p len %d fc %04x sn %d\n",
+			    skb, skb->len, fc, sn);
+		wcn36xx_dbg_dump(WCN36XX_DBG_RX_DUMP, "SKB <<< ",
+				 (char *)skb->data, skb->len);
+	}
+
+	ieee80211_rx_irqsafe(wcn->hw, skb);
+
+	return 0;
+}
+
+static void wcn36xx_set_tx_pdu(struct wcn36xx_tx_bd *bd,
+			       u32 mpdu_header_len,
+			       u32 len,
+			       u16 tid)
+{
+	bd->pdu.mpdu_header_len = mpdu_header_len;
+	bd->pdu.mpdu_header_off = sizeof(*bd);
+	bd->pdu.mpdu_data_off = bd->pdu.mpdu_header_len +
+		bd->pdu.mpdu_header_off;
+	bd->pdu.mpdu_len = len;
+	bd->pdu.tid = tid;
+	bd->pdu.bd_ssn = WCN36XX_TXBD_SSN_FILL_DPU_QOS;
+}
+
+static inline struct wcn36xx_vif *get_vif_by_addr(struct wcn36xx *wcn,
+						  u8 *addr)
+{
+	struct wcn36xx_vif *vif_priv = NULL;
+	struct ieee80211_vif *vif = NULL;
+	list_for_each_entry(vif_priv, &wcn->vif_list, list) {
+			vif = container_of((void *)vif_priv,
+				   struct ieee80211_vif,
+				   drv_priv);
+			if (memcmp(vif->addr, addr, ETH_ALEN) == 0)
+				return vif_priv;
+	}
+	wcn36xx_warn("vif %pM not found\n", addr);
+	return NULL;
+}
+
+static void wcn36xx_tx_start_ampdu(struct wcn36xx *wcn,
+				   struct wcn36xx_sta *sta_priv,
+				   struct sk_buff *skb)
+{
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+	struct ieee80211_sta *sta;
+	u8 *qc, tid;
+
+	if (!conf_is_ht(&wcn->hw->conf))
+		return;
+
+	sta = wcn36xx_priv_to_sta(sta_priv);
+
+	if (WARN_ON(!ieee80211_is_data_qos(hdr->frame_control)))
+		return;
+
+	if (skb_get_queue_mapping(skb) == IEEE80211_AC_VO)
+		return;
+
+	qc = ieee80211_get_qos_ctl(hdr);
+	tid = qc[0] & IEEE80211_QOS_CTL_TID_MASK;
+
+	spin_lock(&sta_priv->ampdu_lock);
+	if (sta_priv->ampdu_state[tid] != WCN36XX_AMPDU_NONE)
+		goto out_unlock;
+
+	if (sta_priv->non_agg_frame_ct++ >= WCN36XX_AMPDU_START_THRESH) {
+		sta_priv->ampdu_state[tid] = WCN36XX_AMPDU_START;
+		sta_priv->non_agg_frame_ct = 0;
+		ieee80211_start_tx_ba_session(sta, tid, 0);
+	}
+out_unlock:
+	spin_unlock(&sta_priv->ampdu_lock);
+}
+
+static void wcn36xx_set_tx_data(struct wcn36xx_tx_bd *bd,
+				struct wcn36xx *wcn,
+				struct wcn36xx_vif **vif_priv,
+				struct wcn36xx_sta *sta_priv,
+				struct sk_buff *skb,
+				bool bcast)
+{
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+	struct ieee80211_vif *vif = NULL;
+	struct wcn36xx_vif *__vif_priv = NULL;
+	bool is_data_qos;
+
+	bd->bd_rate = WCN36XX_BD_RATE_DATA;
+
+	/*
+	 * For not unicast frames mac80211 will not set sta pointer so use
+	 * self_sta_index instead.
+	 */
+	if (sta_priv) {
+		__vif_priv = sta_priv->vif;
+		vif = container_of((void *)__vif_priv,
+				   struct ieee80211_vif,
+				   drv_priv);
+
+		bd->dpu_sign = sta_priv->ucast_dpu_sign;
+		if (vif->type == NL80211_IFTYPE_STATION) {
+			bd->sta_index = sta_priv->bss_sta_index;
+			bd->dpu_desc_idx = sta_priv->bss_dpu_desc_index;
+		} else if (vif->type == NL80211_IFTYPE_AP ||
+			   vif->type == NL80211_IFTYPE_ADHOC ||
+			   vif->type == NL80211_IFTYPE_MESH_POINT) {
+			bd->sta_index = sta_priv->sta_index;
+			bd->dpu_desc_idx = sta_priv->dpu_desc_index;
+		}
+	} else {
+		__vif_priv = get_vif_by_addr(wcn, hdr->addr2);
+		bd->sta_index = __vif_priv->self_sta_index;
+		bd->dpu_desc_idx = __vif_priv->self_dpu_desc_index;
+		bd->dpu_sign = __vif_priv->self_ucast_dpu_sign;
+	}
+
+	if (ieee80211_is_nullfunc(hdr->frame_control) ||
+	   (sta_priv && !sta_priv->is_data_encrypted))
+		bd->dpu_ne = 1;
+
+	if (bcast) {
+		bd->ub = 1;
+		bd->ack_policy = 1;
+	}
+	*vif_priv = __vif_priv;
+
+	is_data_qos = ieee80211_is_data_qos(hdr->frame_control);
+
+	wcn36xx_set_tx_pdu(bd,
+			   is_data_qos ?
+			   sizeof(struct ieee80211_qos_hdr) :
+			   sizeof(struct ieee80211_hdr_3addr),
+			   skb->len, sta_priv ? sta_priv->tid : 0);
+
+	if (sta_priv && is_data_qos)
+		wcn36xx_tx_start_ampdu(wcn, sta_priv, skb);
+}
+
+static void wcn36xx_set_tx_mgmt(struct wcn36xx_tx_bd *bd,
+				struct wcn36xx *wcn,
+				struct wcn36xx_vif **vif_priv,
+				struct sk_buff *skb,
+				bool bcast)
+{
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+	struct wcn36xx_vif *__vif_priv =
+		get_vif_by_addr(wcn, hdr->addr2);
+	bd->sta_index = __vif_priv->self_sta_index;
+	bd->dpu_desc_idx = __vif_priv->self_dpu_desc_index;
+	bd->dpu_ne = 1;
+
+	/* default rate for unicast */
+	if (ieee80211_is_mgmt(hdr->frame_control))
+		bd->bd_rate = (WCN36XX_BAND(wcn) == IEEE80211_BAND_5GHZ) ?
+			WCN36XX_BD_RATE_CTRL :
+			WCN36XX_BD_RATE_MGMT;
+	else if (ieee80211_is_ctl(hdr->frame_control))
+		bd->bd_rate = WCN36XX_BD_RATE_CTRL;
+	else
+		wcn36xx_warn("frame control type unknown\n");
+
+	/*
+	 * In joining state trick hardware that probe is sent as
+	 * unicast even if address is broadcast.
+	 */
+	if (__vif_priv->is_joining &&
+	    ieee80211_is_probe_req(hdr->frame_control))
+		bcast = false;
+
+	if (bcast) {
+		/* broadcast */
+		bd->ub = 1;
+		/* No ack needed not unicast */
+		bd->ack_policy = 1;
+		bd->queue_id = WCN36XX_TX_B_WQ_ID;
+	} else
+		bd->queue_id = WCN36XX_TX_U_WQ_ID;
+	*vif_priv = __vif_priv;
+
+	wcn36xx_set_tx_pdu(bd,
+			   ieee80211_is_data_qos(hdr->frame_control) ?
+			   sizeof(struct ieee80211_qos_hdr) :
+			   sizeof(struct ieee80211_hdr_3addr),
+			   skb->len, WCN36XX_TID);
+}
+
+int wcn36xx_start_tx(struct wcn36xx *wcn,
+		     struct wcn36xx_sta *sta_priv,
+		     struct sk_buff *skb)
+{
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+	struct wcn36xx_vif *vif_priv = NULL;
+	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+	unsigned long flags;
+	bool is_low = ieee80211_is_data(hdr->frame_control);
+	bool bcast = is_broadcast_ether_addr(hdr->addr1) ||
+		is_multicast_ether_addr(hdr->addr1);
+	struct wcn36xx_tx_bd *bd = wcn36xx_dxe_get_next_bd(wcn, is_low);
+
+	if (!bd) {
+		/*
+		 * TX DXE are used in pairs. One for the BD and one for the
+		 * actual frame. The BD DXE's has a preallocated buffer while
+		 * the skb ones does not. If this isn't true something is really
+		 * wierd. TODO: Recover from this situation
+		 */
+
+		wcn36xx_err("bd address may not be NULL for BD DXE\n");
+		return -EINVAL;
+	}
+
+	memset(bd, 0, sizeof(*bd));
+
+	wcn36xx_dbg(WCN36XX_DBG_TX,
+		    "tx skb %p len %d fc %04x sn %d %s %s\n",
+		    skb, skb->len, __le16_to_cpu(hdr->frame_control),
+		    IEEE80211_SEQ_TO_SN(__le16_to_cpu(hdr->seq_ctrl)),
+		    is_low ? "low" : "high", bcast ? "bcast" : "ucast");
+
+	wcn36xx_dbg_dump(WCN36XX_DBG_TX_DUMP, "", skb->data, skb->len);
+
+	bd->dpu_rf = WCN36XX_BMU_WQ_TX;
+
+	bd->tx_comp = !!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS);
+	if (bd->tx_comp) {
+		wcn36xx_dbg(WCN36XX_DBG_DXE, "TX_ACK status requested\n");
+		spin_lock_irqsave(&wcn->dxe_lock, flags);
+		if (wcn->tx_ack_skb) {
+			spin_unlock_irqrestore(&wcn->dxe_lock, flags);
+			wcn36xx_warn("tx_ack_skb already set\n");
+			return -EINVAL;
+		}
+
+		wcn->tx_ack_skb = skb;
+		spin_unlock_irqrestore(&wcn->dxe_lock, flags);
+
+		/* Only one at a time is supported by fw. Stop the TX queues
+		 * until the ack status gets back.
+		 *
+		 * TODO: Add watchdog in case FW does not answer
+		 */
+		ieee80211_stop_queues(wcn->hw);
+	}
+
+	/* Data frames served first*/
+	if (is_low)
+		wcn36xx_set_tx_data(bd, wcn, &vif_priv, sta_priv, skb, bcast);
+	else
+		/* MGMT and CTRL frames are handeld here*/
+		wcn36xx_set_tx_mgmt(bd, wcn, &vif_priv, skb, bcast);
+
+	buff_to_be((u32 *)bd, sizeof(*bd)/sizeof(u32));
+	bd->tx_bd_sign = 0xbdbdbdbd;
+
+	return wcn36xx_dxe_tx_frame(wcn, vif_priv, skb, is_low);
+}