ath6kl: Add HTC pipe implementation

This is needed for USB.

Based on code by Kevin Fang.
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath6kl/Makefile

@@ -26,6 +26,7 @@ obj-$(CONFIG_ATH6KL) += ath6kl_core.o
 ath6kl_core-y += debug.o
 ath6kl_core-y += hif.o
 ath6kl_core-y += htc_mbox.o
+ath6kl_core-y += htc_pipe.o
 ath6kl_core-y += bmi.o
 ath6kl_core-y += cfg80211.o
 ath6kl_core-y += init.o

drivers/net/wireless/ath/ath6kl/core.c

@@ -40,6 +40,18 @@ module_param(uart_debug, uint, 0644);
 module_param(ath6kl_p2p, uint, 0644);
 module_param(testmode, uint, 0644);
 
+void ath6kl_core_tx_complete(struct ath6kl *ar, struct sk_buff *skb)
+{
+	ath6kl_htc_tx_complete(ar, skb);
+}
+EXPORT_SYMBOL(ath6kl_core_tx_complete);
+
+void ath6kl_core_rx_complete(struct ath6kl *ar, struct sk_buff *skb, u8 pipe)
+{
+	ath6kl_htc_rx_complete(ar, skb, pipe);
+}
+EXPORT_SYMBOL(ath6kl_core_rx_complete);
+
 int ath6kl_core_init(struct ath6kl *ar, enum ath6kl_htc_type htc_type)
 {
 	struct ath6kl_bmi_target_info targ_info;
@@ -50,6 +62,9 @@ int ath6kl_core_init(struct ath6kl *ar, enum ath6kl_htc_type htc_type)
 	case ATH6KL_HTC_TYPE_MBOX:
 		ath6kl_htc_mbox_attach(ar);
 		break;
+	case ATH6KL_HTC_TYPE_PIPE:
+		ath6kl_htc_pipe_attach(ar);
+		break;
 	default:
 		WARN_ON(1);
 		return -ENOMEM;

drivers/net/wireless/ath/ath6kl/core.h

@@ -464,6 +464,7 @@ enum ath6kl_hif_type {
 
 enum ath6kl_htc_type {
 	ATH6KL_HTC_TYPE_MBOX,
+	ATH6KL_HTC_TYPE_PIPE,
 };
 
 /* Max number of filters that hw supports */
@@ -835,6 +836,9 @@ int ath6kl_init_hw_params(struct ath6kl *ar);
 
 void ath6kl_check_wow_status(struct ath6kl *ar);
 
+void ath6kl_core_tx_complete(struct ath6kl *ar, struct sk_buff *skb);
+void ath6kl_core_rx_complete(struct ath6kl *ar, struct sk_buff *skb, u8 pipe);
+
 struct ath6kl *ath6kl_core_create(struct device *dev);
 int ath6kl_core_init(struct ath6kl *ar, enum ath6kl_htc_type htc_type);
 void ath6kl_core_cleanup(struct ath6kl *ar);

drivers/net/wireless/ath/ath6kl/hif-ops.h

@@ -150,4 +150,38 @@ static inline void ath6kl_hif_stop(struct ath6kl *ar)
 	ar->hif_ops->stop(ar);
 }
 
+static inline int ath6kl_hif_pipe_send(struct ath6kl *ar,
+				       u8 pipe, struct sk_buff *hdr_buf,
+				       struct sk_buff *buf)
+{
+	ath6kl_dbg(ATH6KL_DBG_HIF, "hif pipe send\n");
+
+	return ar->hif_ops->pipe_send(ar, pipe, hdr_buf, buf);
+}
+
+static inline void ath6kl_hif_pipe_get_default(struct ath6kl *ar,
+					       u8 *ul_pipe, u8 *dl_pipe)
+{
+	ath6kl_dbg(ATH6KL_DBG_HIF, "hif pipe get default\n");
+
+	ar->hif_ops->pipe_get_default(ar, ul_pipe, dl_pipe);
+}
+
+static inline int ath6kl_hif_pipe_map_service(struct ath6kl *ar,
+					      u16 service_id, u8 *ul_pipe,
+					      u8 *dl_pipe)
+{
+	ath6kl_dbg(ATH6KL_DBG_HIF, "hif pipe get default\n");
+
+	return ar->hif_ops->pipe_map_service(ar, service_id, ul_pipe, dl_pipe);
+}
+
+static inline u16 ath6kl_hif_pipe_get_free_queue_number(struct ath6kl *ar,
+							u8 pipe)
+{
+	ath6kl_dbg(ATH6KL_DBG_HIF, "hif pipe get free queue number\n");
+
+	return ar->hif_ops->pipe_get_free_queue_number(ar, pipe);
+}
+
 #endif

drivers/net/wireless/ath/ath6kl/hif.h

@@ -256,6 +256,12 @@ struct ath6kl_hif_ops {
 	int (*power_on)(struct ath6kl *ar);
 	int (*power_off)(struct ath6kl *ar);
 	void (*stop)(struct ath6kl *ar);
+	int (*pipe_send)(struct ath6kl *ar, u8 pipe, struct sk_buff *hdr_buf,
+			 struct sk_buff *buf);
+	void (*pipe_get_default)(struct ath6kl *ar, u8 *pipe_ul, u8 *pipe_dl);
+	int (*pipe_map_service)(struct ath6kl *ar, u16 service_id, u8 *pipe_ul,
+				u8 *pipe_dl);
+	u16 (*pipe_get_free_queue_number)(struct ath6kl *ar, u8 pipe);
 };
 
 int ath6kl_hif_setup(struct ath6kl_device *dev);

drivers/net/wireless/ath/ath6kl/htc.h

@@ -25,6 +25,7 @@
 /* send direction */
 #define HTC_FLAGS_NEED_CREDIT_UPDATE (1 << 0)
 #define HTC_FLAGS_SEND_BUNDLE        (1 << 1)
+#define HTC_FLAGS_TX_FIXUP_NETBUF    (1 << 2)
 
 /* receive direction */
 #define HTC_FLG_RX_UNUSED        (1 << 0)
@@ -56,6 +57,10 @@
 #define HTC_CONN_FLGS_THRESH_LVL_THREE_QUAT	0x2
 #define HTC_CONN_FLGS_REDUCE_CRED_DRIB		0x4
 #define HTC_CONN_FLGS_THRESH_MASK		0x3
+/* disable credit flow control on a specific service */
+#define HTC_CONN_FLGS_DISABLE_CRED_FLOW_CTRL          (1 << 3)
+#define HTC_CONN_FLGS_SET_RECV_ALLOC_SHIFT    8
+#define HTC_CONN_FLGS_SET_RECV_ALLOC_MASK     0xFF00
 
 /* connect response status codes */
 #define HTC_SERVICE_SUCCESS      0
@@ -75,6 +80,7 @@
 #define HTC_RECORD_LOOKAHEAD_BUNDLE 3
 
 #define HTC_SETUP_COMP_FLG_RX_BNDL_EN     (1 << 0)
+#define HTC_SETUP_COMP_FLG_DISABLE_TX_CREDIT_FLOW (1 << 1)
 
 #define MAKE_SERVICE_ID(group, index) \
 	(int)(((int)group << 8) | (int)(index))
@@ -109,6 +115,8 @@
 
 /* HTC operational parameters */
 #define HTC_TARGET_RESPONSE_TIMEOUT        2000	/* in ms */
+#define HTC_TARGET_RESPONSE_POLL_WAIT      10
+#define HTC_TARGET_RESPONSE_POLL_COUNT     200
 #define HTC_TARGET_DEBUG_INTR_MASK         0x01
 #define HTC_TARGET_CREDIT_INTR_MASK        0xF0
 
@@ -128,6 +136,7 @@
 
 #define HTC_RECV_WAIT_BUFFERS        (1 << 0)
 #define HTC_OP_STATE_STOPPING        (1 << 0)
+#define HTC_OP_STATE_SETUP_COMPLETE  (1 << 1)
 
 /*
  * The frame header length and message formats defined herein were selected
@@ -512,6 +521,13 @@ struct htc_endpoint {
 	u32 conn_flags;
 	struct htc_endpoint_stats ep_st;
 	u16 tx_drop_packet_threshold;
+
+	struct {
+		u8 pipeid_ul;
+		u8 pipeid_dl;
+		struct list_head tx_lookup_queue;
+		bool tx_credit_flow_enabled;
+	} pipe;
 };
 
 struct htc_control_buffer {
@@ -519,6 +535,16 @@ struct htc_control_buffer {
 	u8 *buf;
 };
 
+struct htc_pipe_txcredit_alloc {
+	u16 service_id;
+	u8 credit_alloc;
+};
+
+enum htc_send_queue_result {
+	HTC_SEND_QUEUE_OK = 0,	/* packet was queued */
+	HTC_SEND_QUEUE_DROP = 1,	/* this packet should be dropped */
+};
+
 struct ath6kl_htc_ops {
 	void* (*create)(struct ath6kl *ar);
 	int (*wait_target)(struct htc_target *target);
@@ -593,6 +619,14 @@ struct htc_target {
 
 	/* counts the number of Tx without bundling continously per AC */
 	u32 ac_tx_count[WMM_NUM_AC];
+
+	struct {
+		struct htc_packet *htc_packet_pool;
+		u8 ctrl_response_buf[HTC_MAX_CTRL_MSG_LEN];
+		int ctrl_response_len;
+		bool ctrl_response_valid;
+		struct htc_pipe_txcredit_alloc txcredit_alloc[ENDPOINT_MAX];
+	} pipe;
 };
 
 int ath6kl_htc_rxmsg_pending_handler(struct htc_target *target,
@@ -637,6 +671,7 @@ static inline int get_queue_depth(struct list_head *queue)
 	return depth;
 }
 
+void ath6kl_htc_pipe_attach(struct ath6kl *ar);
 void ath6kl_htc_mbox_attach(struct ath6kl *ar);
 
 #endif

drivers/net/wireless/ath/ath6kl/htc_pipe.c

+/*
+ * Copyright (c) 2007-2011 Atheros Communications Inc.
+ *
+ * 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.
+ */
+
+#include "core.h"
+#include "debug.h"
+#include "hif-ops.h"
+
+#define HTC_PACKET_CONTAINER_ALLOCATION 32
+#define HTC_CONTROL_BUFFER_SIZE (HTC_MAX_CTRL_MSG_LEN + HTC_HDR_LENGTH)
+
+static int ath6kl_htc_pipe_tx(struct htc_target *handle,
+			      struct htc_packet *packet);
+static void ath6kl_htc_pipe_cleanup(struct htc_target *handle);
+
+/* htc pipe tx path */
+static inline void restore_tx_packet(struct htc_packet *packet)
+{
+	if (packet->info.tx.flags & HTC_FLAGS_TX_FIXUP_NETBUF) {
+		skb_pull(packet->skb, sizeof(struct htc_frame_hdr));
+		packet->info.tx.flags &= ~HTC_FLAGS_TX_FIXUP_NETBUF;
+	}
+}
+
+static void do_send_completion(struct htc_endpoint *ep,
+			       struct list_head *queue_to_indicate)
+{
+	struct htc_packet *packet;
+
+	if (list_empty(queue_to_indicate)) {
+		/* nothing to indicate */
+		return;
+	}
+
+	if (ep->ep_cb.tx_comp_multi != NULL) {
+		ath6kl_dbg(ATH6KL_DBG_HTC,
+			   "%s: calling ep %d, send complete multiple callback (%d pkts)\n",
+			   __func__, ep->eid,
+			   get_queue_depth(queue_to_indicate));
+		/*
+		 * a multiple send complete handler is being used,
+		 * pass the queue to the handler
+		 */
+		ep->ep_cb.tx_comp_multi(ep->target, queue_to_indicate);
+		/*
+		 * all packets are now owned by the callback,
+		 * reset queue to be safe
+		 */
+		INIT_LIST_HEAD(queue_to_indicate);
+	} else {
+		/* using legacy EpTxComplete */
+		do {
+			packet = list_first_entry(queue_to_indicate,
+						  struct htc_packet, list);
+
+			list_del(&packet->list);
+			ath6kl_dbg(ATH6KL_DBG_HTC,
+				   "%s: calling ep %d send complete callback on packet 0x%p\n",
+				   __func__, ep->eid, packet);
+			ep->ep_cb.tx_complete(ep->target, packet);
+		} while (!list_empty(queue_to_indicate));
+	}
+}
+
+static void send_packet_completion(struct htc_target *target,
+				   struct htc_packet *packet)
+{
+	struct htc_endpoint *ep = &target->endpoint[packet->endpoint];
+	struct list_head container;
+
+	restore_tx_packet(packet);
+	INIT_LIST_HEAD(&container);
+	list_add_tail(&packet->list, &container);
+
+	/* do completion */
+	do_send_completion(ep, &container);
+}
+
+static void get_htc_packet_credit_based(struct htc_target *target,
+					struct htc_endpoint *ep,
+					struct list_head *queue)
+{
+	int credits_required;
+	int remainder;
+	u8 send_flags;
+	struct htc_packet *packet;
+	unsigned int transfer_len;
+
+	/* NOTE : the TX lock is held when this function is called */
+
+	/* loop until we can grab as many packets out of the queue as we can */
+	while (true) {
+		send_flags = 0;
+		if (list_empty(&ep->txq))
+			break;
+
+		/* get packet at head, but don't remove it */
+		packet = list_first_entry(&ep->txq, struct htc_packet, list);
+		if (packet == NULL)
+			break;
+
+		ath6kl_dbg(ATH6KL_DBG_HTC,
+			   "%s: got head packet:0x%p , queue depth: %d\n",
+			   __func__, packet, get_queue_depth(&ep->txq));
+
+		transfer_len = packet->act_len + HTC_HDR_LENGTH;
+
+		if (transfer_len <= target->tgt_cred_sz) {
+			credits_required = 1;
+		} else {
+			/* figure out how many credits this message requires */
+			credits_required = transfer_len / target->tgt_cred_sz;
+			remainder = transfer_len % target->tgt_cred_sz;
+
+			if (remainder)
+				credits_required++;
+		}
+
+		ath6kl_dbg(ATH6KL_DBG_HTC, "%s: creds required:%d got:%d\n",
+			   __func__, credits_required, ep->cred_dist.credits);
+
+		if (ep->eid == ENDPOINT_0) {
+			/*
+			 * endpoint 0 is special, it always has a credit and
+			 * does not require credit based flow control
+			 */
+			credits_required = 0;
+
+		} else {
+
+			if (ep->cred_dist.credits < credits_required)
+				break;
+
+			ep->cred_dist.credits -= credits_required;
+			ep->ep_st.cred_cosumd += credits_required;
+
+			/* check if we need credits back from the target */
+			if (ep->cred_dist.credits <
+					ep->cred_dist.cred_per_msg) {
+				/* tell the target we need credits ASAP! */
+				send_flags |= HTC_FLAGS_NEED_CREDIT_UPDATE;
+				ep->ep_st.cred_low_indicate += 1;
+				ath6kl_dbg(ATH6KL_DBG_HTC,
+					   "%s: host needs credits\n",
+					   __func__);
+			}
+		}
+
+		/* now we can fully dequeue */
+		packet = list_first_entry(&ep->txq, struct htc_packet, list);
+
+		list_del(&packet->list);
+		/* save the number of credits this packet consumed */
+		packet->info.tx.cred_used = credits_required;
+		/* save send flags */
+		packet->info.tx.flags = send_flags;
+		packet->info.tx.seqno = ep->seqno;
+		ep->seqno++;
+		/* queue this packet into the caller's queue */
+		list_add_tail(&packet->list, queue);
+	}
+
+}
+
+static void get_htc_packet(struct htc_target *target,
+			   struct htc_endpoint *ep,
+			   struct list_head *queue, int resources)
+{
+	struct htc_packet *packet;
+
+	/* NOTE : the TX lock is held when this function is called */
+
+	/* loop until we can grab as many packets out of the queue as we can */
+	while (resources) {
+		if (list_empty(&ep->txq))
+			break;
+
+		packet = list_first_entry(&ep->txq, struct htc_packet, list);
+		list_del(&packet->list);
+
+		ath6kl_dbg(ATH6KL_DBG_HTC,
+			   "%s: got packet:0x%p , new queue depth: %d\n",
+			   __func__, packet, get_queue_depth(&ep->txq));
+		packet->info.tx.seqno = ep->seqno;
+		packet->info.tx.flags = 0;
+		packet->info.tx.cred_used = 0;
+		ep->seqno++;
+
+		/* queue this packet into the caller's queue */
+		list_add_tail(&packet->list, queue);
+		resources--;
+	}
+}
+
+static int htc_issue_packets(struct htc_target *target,
+			     struct htc_endpoint *ep,
+			     struct list_head *pkt_queue)
+{
+	int status = 0;
+	u16 payload_len;
+	struct sk_buff *skb;
+	struct htc_frame_hdr *htc_hdr;
+	struct htc_packet *packet;
+
+	ath6kl_dbg(ATH6KL_DBG_HTC,
+		   "%s: queue: 0x%p, pkts %d\n", __func__,
+		   pkt_queue, get_queue_depth(pkt_queue));
+
+	while (!list_empty(pkt_queue)) {
+		packet = list_first_entry(pkt_queue, struct htc_packet, list);
+		list_del(&packet->list);
+
+		skb = packet->skb;
+		if (!skb) {
+			WARN_ON_ONCE(1);
+			status = -EINVAL;
+			break;
+		}
+
+		payload_len = packet->act_len;
+
+		/* setup HTC frame header */
+		htc_hdr = (struct htc_frame_hdr *) skb_push(skb,
+							    sizeof(*htc_hdr));
+		if (!htc_hdr) {
+			WARN_ON_ONCE(1);
+			status = -EINVAL;
+			break;
+		}
+
+		packet->info.tx.flags |= HTC_FLAGS_TX_FIXUP_NETBUF;
+
+		/* Endianess? */
+		put_unaligned((u16) payload_len, &htc_hdr->payld_len);
+		htc_hdr->flags = packet->info.tx.flags;
+		htc_hdr->eid = (u8) packet->endpoint;
+		htc_hdr->ctrl[0] = 0;
+		htc_hdr->ctrl[1] = (u8) packet->info.tx.seqno;
+
+		spin_lock_bh(&target->tx_lock);
+
+		/* store in look up queue to match completions */
+		list_add_tail(&packet->list, &ep->pipe.tx_lookup_queue);
+		ep->ep_st.tx_issued += 1;
+		spin_unlock_bh(&target->tx_lock);
+
+		status = ath6kl_hif_pipe_send(target->dev->ar,
+					      ep->pipe.pipeid_ul, NULL, skb);
+
+		if (status != 0) {
+			if (status != -ENOMEM) {
+				/* TODO: if more than 1 endpoint maps to the
+				 * same PipeID, it is possible to run out of
+				 * resources in the HIF layer.
+				 * Don't emit the error
+				 */
+				ath6kl_dbg(ATH6KL_DBG_HTC,
+					   "%s: failed status:%d\n",
+					   __func__, status);
+			}
+			spin_lock_bh(&target->tx_lock);
+			list_del(&packet->list);
+
+			/* reclaim credits */
+			ep->cred_dist.credits += packet->info.tx.cred_used;
+			spin_unlock_bh(&target->tx_lock);
+
+			/* put it back into the callers queue */
+			list_add(&packet->list, pkt_queue);
+			break;
+		}
+
+	}
+
+	if (status != 0) {
+		while (!list_empty(pkt_queue)) {
+			if (status != -ENOMEM) {
+				ath6kl_dbg(ATH6KL_DBG_HTC,
+					   "%s: failed pkt:0x%p status:%d\n",
+					   __func__, packet, status);
+			}
+
+			packet = list_first_entry(pkt_queue,
+						  struct htc_packet, list);
+			list_del(&packet->list);
+			packet->status = status;
+			send_packet_completion(target, packet);
+		}
+	}
+
+	return status;
+}
+
+static enum htc_send_queue_result htc_try_send(struct htc_target *target,
+					       struct htc_endpoint *ep,
+					       struct list_head *txq)
+{
+	struct list_head send_queue;	/* temp queue to hold packets */
+	struct htc_packet *packet, *tmp_pkt;
+	struct ath6kl *ar = target->dev->ar;
+	enum htc_send_full_action action;
+	int tx_resources, overflow, txqueue_depth, i, good_pkts;
+	u8 pipeid;
+
+	ath6kl_dbg(ATH6KL_DBG_HTC, "%s: (queue:0x%p depth:%d)\n",
+		   __func__, txq,
+		   (txq == NULL) ? 0 : get_queue_depth(txq));
+
+	/* init the local send queue */
+	INIT_LIST_HEAD(&send_queue);
+
+	/*
+	 * txq equals to NULL means
+	 * caller didn't provide a queue, just wants us to
+	 * check queues and send
+	 */
+	if (txq != NULL) {
+		if (list_empty(txq)) {
+			/* empty queue */
+			return HTC_SEND_QUEUE_DROP;
+		}
+
+		spin_lock_bh(&target->tx_lock);
+		txqueue_depth = get_queue_depth(&ep->txq);
+		spin_unlock_bh(&target->tx_lock);
+
+		if (txqueue_depth >= ep->max_txq_depth) {
+			/* we've already overflowed */
+			overflow = get_queue_depth(txq);
+		} else {
+			/* get how much we will overflow by */
+			overflow = txqueue_depth;
+			overflow += get_queue_depth(txq);
+			/* get how much we will overflow the TX queue by */
+			overflow -= ep->max_txq_depth;
+		}
+
+		/* if overflow is negative or zero, we are okay */
+		if (overflow > 0) {
+			ath6kl_dbg(ATH6KL_DBG_HTC,
+				   "%s: Endpoint %d, TX queue will overflow :%d, Tx Depth:%d, Max:%d\n",
+				   __func__, ep->eid, overflow, txqueue_depth,
+				   ep->max_txq_depth);
+		}
+		if ((overflow <= 0) ||
+		    (ep->ep_cb.tx_full == NULL)) {
+			/*
+			 * all packets will fit or caller did not provide send
+			 * full indication handler -- just move all of them
+			 * to the local send_queue object
+			 */
+			list_splice_tail_init(txq, &send_queue);
+		} else {
+			good_pkts = get_queue_depth(txq) - overflow;
+			if (good_pkts < 0) {
+				WARN_ON_ONCE(1);
+				return HTC_SEND_QUEUE_DROP;
+			}
+
+			/* we have overflowed, and a callback is provided */
+			/* dequeue all non-overflow packets to the sendqueue */
+			for (i = 0; i < good_pkts; i++) {
+				/* pop off caller's queue */
+				packet = list_first_entry(txq,
+							  struct htc_packet,
+							  list);
+				list_del(&packet->list);
+				/* insert into local queue */
+				list_add_tail(&packet->list, &send_queue);
+			}
+
+			/*
+			 * the caller's queue has all the packets that won't fit
+			 * walk through the caller's queue and indicate each to
+			 * the send full handler
+			 */
+			list_for_each_entry_safe(packet, tmp_pkt,
+						 txq, list) {
+
+				ath6kl_dbg(ATH6KL_DBG_HTC,
+					   "%s: Indicat overflowed TX pkts: %p\n",
+					   __func__, packet);
+				action = ep->ep_cb.tx_full(ep->target, packet);
+				if (action == HTC_SEND_FULL_DROP) {
+					/* callback wants the packet dropped */
+					ep->ep_st.tx_dropped += 1;
+
+					/* leave this one in the caller's queue
+					 * for cleanup */
+				} else {
+					/* callback wants to keep this packet,
+					 * remove from caller's queue */
+					list_del(&packet->list);
+					/* put it in the send queue */
+					list_add_tail(&packet->list,
+						      &send_queue);
+				}
+
+			}
+
+			if (list_empty(&send_queue)) {
+				/* no packets made it in, caller will cleanup */
+				return HTC_SEND_QUEUE_DROP;
+			}
+		}
+	}
+
+	if (!ep->pipe.tx_credit_flow_enabled) {
+		tx_resources =
+		    ath6kl_hif_pipe_get_free_queue_number(ar,
+							  ep->pipe.pipeid_ul);
+	} else {
+		tx_resources = 0;
+	}
+
+	spin_lock_bh(&target->tx_lock);
+	if (!list_empty(&send_queue)) {
+		/* transfer packets to tail */
+		list_splice_tail_init(&send_queue, &ep->txq);
+		if (!list_empty(&send_queue)) {
+			WARN_ON_ONCE(1);
+			spin_unlock_bh(&target->tx_lock);
+			return HTC_SEND_QUEUE_DROP;
+		}
+		INIT_LIST_HEAD(&send_queue);
+	}
+
+	/* increment tx processing count on entry */
+	ep->tx_proc_cnt++;
+
+	if (ep->tx_proc_cnt > 1) {
+		/*
+		 * Another thread or task is draining the TX queues on this
+		 * endpoint that thread will reset the tx processing count
+		 * when the queue is drained.
+		 */
+		ep->tx_proc_cnt--;
+		spin_unlock_bh(&target->tx_lock);
+		return HTC_SEND_QUEUE_OK;
+	}
+
+	/***** beyond this point only 1 thread may enter ******/
+
+	/*
+	 * Now drain the endpoint TX queue for transmission as long as we have
+	 * enough transmit resources.
+	 */
+	while (true) {
+
+		if (get_queue_depth(&ep->txq) == 0)
+			break;
+
+		if (ep->pipe.tx_credit_flow_enabled) {
+			/*
+			 * Credit based mechanism provides flow control
+			 * based on target transmit resource availability,
+			 * we assume that the HIF layer will always have
+			 * bus resources greater than target transmit
+			 * resources.
+			 */
+			get_htc_packet_credit_based(target, ep, &send_queue);
+		} else {
+			/*
+			 * Get all packets for this endpoint that we can
+			 * for this pass.
+			 */
+			get_htc_packet(target, ep, &send_queue, tx_resources);
+		}
+
+		if (get_queue_depth(&send_queue) == 0) {
+			/*
+			 * Didn't get packets due to out of resources or TX
+			 * queue was drained.
+			 */
+			break;
+		}
+
+		spin_unlock_bh(&target->tx_lock);
+
+		/* send what we can */
+		htc_issue_packets(target, ep, &send_queue);
+
+		if (!ep->pipe.tx_credit_flow_enabled) {
+			pipeid = ep->pipe.pipeid_ul;
+			tx_resources =
+			    ath6kl_hif_pipe_get_free_queue_number(ar, pipeid);
+		}
+
+		spin_lock_bh(&target->tx_lock);
+
+	}
+	/* done with this endpoint, we can clear the count */
+	ep->tx_proc_cnt = 0;
+	spin_unlock_bh(&target->tx_lock);
+
+	return HTC_SEND_QUEUE_OK;
+}
+
+/* htc control packet manipulation */
+static void destroy_htc_txctrl_packet(struct htc_packet *packet)
+{
+	struct sk_buff *skb;
+	skb = packet->skb;
+	if (skb != NULL)
+		dev_kfree_skb(skb);
+
+	kfree(packet);
+}
+
+static struct htc_packet *build_htc_txctrl_packet(void)
+{
+	struct htc_packet *packet = NULL;
+	struct sk_buff *skb;
+
+	packet = kzalloc(sizeof(struct htc_packet), GFP_KERNEL);
+	if (packet == NULL)
+		return NULL;
+
+	skb = __dev_alloc_skb(HTC_CONTROL_BUFFER_SIZE, GFP_KERNEL);
+
+	if (skb == NULL) {
+		kfree(packet);
+		return NULL;
+	}
+	packet->skb = skb;
+
+	return packet;
+}
+
+static void htc_free_txctrl_packet(struct htc_target *target,
+				   struct htc_packet *packet)
+{
+	destroy_htc_txctrl_packet(packet);
+}
+
+static struct htc_packet *htc_alloc_txctrl_packet(struct htc_target *target)
+{
+	return build_htc_txctrl_packet();
+}
+
+static void htc_txctrl_complete(struct htc_target *target,
+				struct htc_packet *packet)
+{
+	htc_free_txctrl_packet(target, packet);
+}
+
+#define MAX_MESSAGE_SIZE 1536
+
+static int htc_setup_target_buffer_assignments(struct htc_target *target)
+{
+	int status, credits, credit_per_maxmsg, i;
+	struct htc_pipe_txcredit_alloc *entry;
+	unsigned int hif_usbaudioclass = 0;
+
+	credit_per_maxmsg = MAX_MESSAGE_SIZE / target->tgt_cred_sz;
+	if (MAX_MESSAGE_SIZE % target->tgt_cred_sz)
+		credit_per_maxmsg++;
+
+	/* TODO, this should be configured by the caller! */
+
+	credits = target->tgt_creds;
+	entry = &target->pipe.txcredit_alloc[0];
+
+	status = -ENOMEM;
+
+	/* FIXME: hif_usbaudioclass is always zero */
+	if (hif_usbaudioclass) {
+		ath6kl_dbg(ATH6KL_DBG_HTC,
+			   "%s: For USB Audio Class- Total:%d\n",
+			   __func__, credits);
+		entry++;
+		entry++;
+		/* Setup VO Service To have Max Credits */
+		entry->service_id = WMI_DATA_VO_SVC;
+		entry->credit_alloc = (credits - 6);
+		if (entry->credit_alloc == 0)
+			entry->credit_alloc++;
+
+		credits -= (int) entry->credit_alloc;
+		if (credits <= 0)
+			return status;
+
+		entry++;
+		entry->service_id = WMI_CONTROL_SVC;
+		entry->credit_alloc = credit_per_maxmsg;
+		credits -= (int) entry->credit_alloc;
+		if (credits <= 0)
+			return status;
+
+		/* leftovers go to best effort */
+		entry++;
+		entry++;
+		entry->service_id = WMI_DATA_BE_SVC;
+		entry->credit_alloc = (u8) credits;
+		status = 0;
+	} else {
+		entry++;
+		entry->service_id = WMI_DATA_VI_SVC;
+		entry->credit_alloc = credits / 4;
+		if (entry->credit_alloc == 0)
+			entry->credit_alloc++;
+
+		credits -= (int) entry->credit_alloc;
+		if (credits <= 0)
+			return status;
+
+		entry++;
+		entry->service_id = WMI_DATA_VO_SVC;
+		entry->credit_alloc = credits / 4;
+		if (entry->credit_alloc == 0)
+			entry->credit_alloc++;
+
+		credits -= (int) entry->credit_alloc;
+		if (credits <= 0)
+			return status;
+
+		entry++;
+		entry->service_id = WMI_CONTROL_SVC;
+		entry->credit_alloc = credit_per_maxmsg;
+		credits -= (int) entry->credit_alloc;
+		if (credits <= 0)
+			return status;
+
+		entry++;
+		entry->service_id = WMI_DATA_BK_SVC;
+		entry->credit_alloc = credit_per_maxmsg;
+		credits -= (int) entry->credit_alloc;
+		if (credits <= 0)
+			return status;
+
+		/* leftovers go to best effort */
+		entry++;
+		entry->service_id = WMI_DATA_BE_SVC;
+		entry->credit_alloc = (u8) credits;
+		status = 0;
+	}
+
+	if (status == 0) {
+		for (i = 0; i < ENDPOINT_MAX; i++) {
+			if (target->pipe.txcredit_alloc[i].service_id != 0) {
+				ath6kl_dbg(ATH6KL_DBG_HTC,
+					   "HTC Service Index : %d TX : 0x%2.2X : alloc:%d\n",
+					   i,
+					   target->pipe.txcredit_alloc[i].
+					   service_id,
+					   target->pipe.txcredit_alloc[i].
+					   credit_alloc);
+			}
+		}
+	}
+	return status;
+}
+
+/* process credit reports and call distribution function */
+static void htc_process_credit_report(struct htc_target *target,
+				      struct htc_credit_report *rpt,
+				      int num_entries,
+				      enum htc_endpoint_id from_ep)
+{
+	int total_credits = 0, i;
+	struct htc_endpoint *ep;
+
+	/* lock out TX while we update credits */
+	spin_lock_bh(&target->tx_lock);
+
+	for (i = 0; i < num_entries; i++, rpt++) {
+		if (rpt->eid >= ENDPOINT_MAX) {
+			WARN_ON_ONCE(1);
+			spin_unlock_bh(&target->tx_lock);
+			return;
+		}
+
+		ep = &target->endpoint[rpt->eid];
+		ep->cred_dist.credits += rpt->credits;
+
+		if (ep->cred_dist.credits && get_queue_depth(&ep->txq)) {
+			spin_unlock_bh(&target->tx_lock);
+			htc_try_send(target, ep, NULL);
+			spin_lock_bh(&target->tx_lock);
+		}
+
+		total_credits += rpt->credits;
+	}
+	ath6kl_dbg(ATH6KL_DBG_HTC,
+		   "Report indicated %d credits to distribute\n",
+		   total_credits);
+
+	spin_unlock_bh(&target->tx_lock);
+}
+
+/* flush endpoint TX queue */
+static void htc_flush_tx_endpoint(struct htc_target *target,
+				  struct htc_endpoint *ep, u16 tag)
+{
+	struct htc_packet *packet;
+
+	spin_lock_bh(&target->tx_lock);
+	while (get_queue_depth(&ep->txq)) {
+		packet = list_first_entry(&ep->txq, struct htc_packet, list);
+		list_del(&packet->list);
+		packet->status = 0;
+		send_packet_completion(target, packet);
+	}
+	spin_unlock_bh(&target->tx_lock);
+}
+
+/*
+ * In the adapted HIF layer, struct sk_buff * are passed between HIF and HTC,
+ * since upper layers expects struct htc_packet containers we use the completed
+ * skb and lookup it's corresponding HTC packet buffer from a lookup list.
+ * This is extra overhead that can be fixed by re-aligning HIF interfaces with
+ * HTC.
+ */
+static struct htc_packet *htc_lookup_tx_packet(struct htc_target *target,
+					       struct htc_endpoint *ep,
+					       struct sk_buff *skb)
+{
+	struct htc_packet *packet, *tmp_pkt, *found_packet = NULL;
+
+	spin_lock_bh(&target->tx_lock);
+
+	/*
+	 * interate from the front of tx lookup queue
+	 * this lookup should be fast since lower layers completes in-order and
+	 * so the completed packet should be at the head of the list generally
+	 */
+	list_for_each_entry_safe(packet, tmp_pkt, &ep->pipe.tx_lookup_queue,
+				 list) {
+		/* check for removal */
+		if (skb == packet->skb) {
+			/* found it */
+			list_del(&packet->list);
+			found_packet = packet;
+			break;
+		}
+	}
+
+	spin_unlock_bh(&target->tx_lock);
+
+	return found_packet;
+}
+
+static int ath6kl_htc_pipe_tx_complete(struct ath6kl *ar, struct sk_buff *skb)
+{
+	struct htc_target *target = ar->htc_target;
+	struct htc_frame_hdr *htc_hdr;
+	struct htc_endpoint *ep;
+	struct htc_packet *packet;
+	u8 ep_id, *netdata;
+	u32 netlen;
+
+	netdata = skb->data;
+	netlen = skb->len;
+
+	htc_hdr = (struct htc_frame_hdr *) netdata;
+
+	ep_id = htc_hdr->eid;
+	ep = &target->endpoint[ep_id];
+
+	packet = htc_lookup_tx_packet(target, ep, skb);
+	if (packet == NULL) {
+		/* may have already been flushed and freed */
+		ath6kl_err("HTC TX lookup failed!\n");
+	} else {
+		/* will be giving this buffer back to upper layers */
+		packet->status = 0;
+		send_packet_completion(target, packet);
+	}
+	skb = NULL;
+
+	if (!ep->pipe.tx_credit_flow_enabled) {
+		/*
+		 * note: when using TX credit flow, the re-checking of queues
+		 * happens when credits flow back from the target. in the
+		 * non-TX credit case, we recheck after the packet completes
+		 */
+		htc_try_send(target, ep, NULL);
+	}
+
+	return 0;
+}
+
+static int htc_send_packets_multiple(struct htc_target *target,
+				     struct list_head *pkt_queue)
+{
+	struct htc_endpoint *ep;
+	struct htc_packet *packet, *tmp_pkt;
+
+	if (list_empty(pkt_queue))
+		return -EINVAL;
+
+	/* get first packet to find out which ep the packets will go into */
+	packet = list_first_entry(pkt_queue, struct htc_packet, list);
+	if (packet == NULL)
+		return -EINVAL;
+
+	if (packet->endpoint >= ENDPOINT_MAX) {
+		WARN_ON_ONCE(1);
+		return -EINVAL;
+	}
+	ep = &target->endpoint[packet->endpoint];
+
+	htc_try_send(target, ep, pkt_queue);
+
+	/* do completion on any packets that couldn't get in */
+	if (!list_empty(pkt_queue)) {
+		list_for_each_entry_safe(packet, tmp_pkt, pkt_queue, list) {
+			packet->status = -ENOMEM;
+		}
+
+		do_send_completion(ep, pkt_queue);
+	}
+
+	return 0;
+}
+
+/* htc pipe rx path */
+static struct htc_packet *alloc_htc_packet_container(struct htc_target *target)
+{
+	struct htc_packet *packet;
+	spin_lock_bh(&target->rx_lock);
+
+	if (target->pipe.htc_packet_pool == NULL) {
+		spin_unlock_bh(&target->rx_lock);
+		return NULL;
+	}
+
+	packet = target->pipe.htc_packet_pool;
+	target->pipe.htc_packet_pool = (struct htc_packet *) packet->list.next;
+
+	spin_unlock_bh(&target->rx_lock);
+
+	packet->list.next = NULL;
+	return packet;
+}
+
+static void free_htc_packet_container(struct htc_target *target,
+				      struct htc_packet *packet)
+{
+	struct list_head *lh;
+
+	spin_lock_bh(&target->rx_lock);
+
+	if (target->pipe.htc_packet_pool == NULL) {
+		target->pipe.htc_packet_pool = packet;
+		packet->list.next = NULL;
+	} else {
+		lh = (struct list_head *) target->pipe.htc_packet_pool;
+		packet->list.next = lh;
+		target->pipe.htc_packet_pool = packet;
+	}
+
+	spin_unlock_bh(&target->rx_lock);
+}
+
+static int htc_process_trailer(struct htc_target *target, u8 *buffer,
+			       int len, enum htc_endpoint_id from_ep)
+{
+	struct htc_credit_report *report;
+	struct htc_record_hdr *record;
+	u8 *record_buf, *orig_buf;
+	int orig_len, status;
+
+	orig_buf = buffer;
+	orig_len = len;
+	status = 0;
+
+	while (len > 0) {
+		if (len < sizeof(struct htc_record_hdr)) {
+			status = -EINVAL;
+			break;
+		}
+
+		/* these are byte aligned structs */
+		record = (struct htc_record_hdr *) buffer;
+		len -= sizeof(struct htc_record_hdr);
+		buffer += sizeof(struct htc_record_hdr);
+
+		if (record->len > len) {
+			/* no room left in buffer for record */
+			ath6kl_dbg(ATH6KL_DBG_HTC,
+				   "invalid length: %d (id:%d) buffer has: %d bytes left\n",
+				   record->len, record->rec_id, len);
+			status = -EINVAL;
+			break;
+		}
+
+		/* start of record follows the header */
+		record_buf = buffer;
+
+		switch (record->rec_id) {
+		case HTC_RECORD_CREDITS:
+			if (record->len < sizeof(struct htc_credit_report)) {
+				WARN_ON_ONCE(1);
+				return -EINVAL;
+			}
+
+			report = (struct htc_credit_report *) record_buf;
+			htc_process_credit_report(target, report,
+						  record->len / sizeof(*report),
+						  from_ep);
+			break;
+		default:
+			ath6kl_dbg(ATH6KL_DBG_HTC,
+				   "unhandled record: id:%d length:%d\n",
+				   record->rec_id, record->len);
+			break;
+		}
+
+		if (status != 0)
+			break;
+
+		/* advance buffer past this record for next time around */
+		buffer += record->len;
+		len -= record->len;
+	}
+
+	return status;
+}
+
+static void do_recv_completion(struct htc_endpoint *ep,
+			       struct list_head *queue_to_indicate)
+{
+	struct htc_packet *packet;
+
+	if (list_empty(queue_to_indicate)) {
+		/* nothing to indicate */
+		return;
+	}
+
+	/* using legacy EpRecv */
+	while (!list_empty(queue_to_indicate)) {
+		packet = list_first_entry(queue_to_indicate,
+					  struct htc_packet, list);
+		list_del(&packet->list);
+		ep->ep_cb.rx(ep->target, packet);
+	}
+
+	return;
+}
+
+static void recv_packet_completion(struct htc_target *target,
+				   struct htc_endpoint *ep,
+				   struct htc_packet *packet)
+{
+	struct list_head container;
+	INIT_LIST_HEAD(&container);
+	list_add_tail(&packet->list, &container);
+
+	/* do completion */
+	do_recv_completion(ep, &container);
+}
+
+static int ath6kl_htc_pipe_rx_complete(struct ath6kl *ar, struct sk_buff *skb,
+				       u8 pipeid)
+{
+	struct htc_target *target = ar->htc_target;
+	u8 *netdata, *trailer, hdr_info;
+	struct htc_frame_hdr *htc_hdr;
+	u32 netlen, trailerlen = 0;
+	struct htc_packet *packet;
+	struct htc_endpoint *ep;
+	u16 payload_len;
+	int status = 0;
+
+	netdata = skb->data;
+	netlen = skb->len;
+
+	htc_hdr = (struct htc_frame_hdr *) netdata;
+
+	ep = &target->endpoint[htc_hdr->eid];
+
+	if (htc_hdr->eid >= ENDPOINT_MAX) {
+		ath6kl_dbg(ATH6KL_DBG_HTC,
+			   "HTC Rx: invalid EndpointID=%d\n",
+			   htc_hdr->eid);
+		status = -EINVAL;
+		goto free_skb;
+	}
+
+	payload_len = le16_to_cpu(get_unaligned(&htc_hdr->payld_len));
+
+	if (netlen < (payload_len + HTC_HDR_LENGTH)) {
+		ath6kl_dbg(ATH6KL_DBG_HTC,
+			   "HTC Rx: insufficient length, got:%d expected =%u\n",
+			   netlen, payload_len + HTC_HDR_LENGTH);
+		status = -EINVAL;
+		goto free_skb;
+	}
+
+	/* get flags to check for trailer */
+	hdr_info = htc_hdr->flags;
+	if (hdr_info & HTC_FLG_RX_TRAILER) {
+		/* extract the trailer length */
+		hdr_info = htc_hdr->ctrl[0];
+		if ((hdr_info < sizeof(struct htc_record_hdr)) ||
+		    (hdr_info > payload_len)) {
+			ath6kl_dbg(ATH6KL_DBG_HTC,
+				   "invalid header: payloadlen should be %d, CB[0]: %d\n",
+				   payload_len, hdr_info);
+			status = -EINVAL;
+			goto free_skb;
+		}
+
+		trailerlen = hdr_info;
+		/* process trailer after hdr/apps payload */
+		trailer = (u8 *) htc_hdr + HTC_HDR_LENGTH +
+			payload_len - hdr_info;
+		status = htc_process_trailer(target, trailer, hdr_info,
+					     htc_hdr->eid);
+		if (status != 0)
+			goto free_skb;
+	}
+
+	if (((int) payload_len - (int) trailerlen) <= 0) {
+		/* zero length packet with trailer, just drop these */
+		goto free_skb;
+	}
+
+	if (htc_hdr->eid == ENDPOINT_0) {
+		/* handle HTC control message */
+		if (target->htc_flags & HTC_OP_STATE_SETUP_COMPLETE) {
+			/*
+			 * fatal: target should not send unsolicited
+			 * messageson the endpoint 0
+			 */
+			ath6kl_dbg(ATH6KL_DBG_HTC,
+				   "HTC ignores Rx Ctrl after setup complete\n");
+			status = -EINVAL;
+			goto free_skb;
+		}
+
+		/* remove HTC header */
+		skb_pull(skb, HTC_HDR_LENGTH);
+
+		netdata = skb->data;
+		netlen = skb->len;
+
+		spin_lock_bh(&target->rx_lock);
+
+		target->pipe.ctrl_response_valid = true;
+		target->pipe.ctrl_response_len = min_t(int, netlen,
+						       HTC_MAX_CTRL_MSG_LEN);
+		memcpy(target->pipe.ctrl_response_buf, netdata,
+		       target->pipe.ctrl_response_len);
+
+		spin_unlock_bh(&target->rx_lock);
+
+		dev_kfree_skb(skb);
+		skb = NULL;
+		goto free_skb;
+	}
+
+	/*
+	 * TODO: the message based HIF architecture allocates net bufs
+	 * for recv packets since it bridges that HIF to upper layers,
+	 * which expects HTC packets, we form the packets here
+	 */
+	packet = alloc_htc_packet_container(target);
+	if (packet == NULL) {
+		status = -ENOMEM;
+		goto free_skb;
+	}
+
+	packet->status = 0;
+	packet->endpoint = htc_hdr->eid;
+	packet->pkt_cntxt = skb;
+
+	/* TODO: for backwards compatibility */
+	packet->buf = skb_push(skb, 0) + HTC_HDR_LENGTH;
+	packet->act_len = netlen - HTC_HDR_LENGTH - trailerlen;
+
+	/*
+	 * TODO: this is a hack because the driver layer will set the
+	 * actual len of the skb again which will just double the len
+	 */
+	skb_trim(skb, 0);
+
+	recv_packet_completion(target, ep, packet);
+
+	/* recover the packet container */
+	free_htc_packet_container(target, packet);
+	skb = NULL;
+
+free_skb:
+	if (skb != NULL)
+		dev_kfree_skb(skb);
+
+	return status;
+
+}
+
+static void htc_flush_rx_queue(struct htc_target *target,
+			       struct htc_endpoint *ep)
+{
+	struct list_head container;
+	struct htc_packet *packet;
+
+	spin_lock_bh(&target->rx_lock);
+
+	while (1) {
+		if (list_empty(&ep->rx_bufq))
+			break;
+
+		packet = list_first_entry(&ep->rx_bufq,
+					  struct htc_packet, list);
+		list_del(&packet->list);
+
+		spin_unlock_bh(&target->rx_lock);
+		packet->status = -ECANCELED;
+		packet->act_len = 0;
+
+		ath6kl_dbg(ATH6KL_DBG_HTC,
+			   "Flushing RX packet:0x%p, length:%d, ep:%d\n",
+			   packet, packet->buf_len,
+			   packet->endpoint);
+
+		INIT_LIST_HEAD(&container);
+		list_add_tail(&packet->list, &container);
+
+		/* give the packet back */
+		do_recv_completion(ep, &container);
+		spin_lock_bh(&target->rx_lock);
+	}
+
+	spin_unlock_bh(&target->rx_lock);
+}
+
+/* polling routine to wait for a control packet to be received */
+static int htc_wait_recv_ctrl_message(struct htc_target *target)
+{
+	int count = HTC_TARGET_RESPONSE_POLL_COUNT;
+
+	while (count > 0) {
+		spin_lock_bh(&target->rx_lock);
+
+		if (target->pipe.ctrl_response_valid) {
+			target->pipe.ctrl_response_valid = false;
+			spin_unlock_bh(&target->rx_lock);
+			break;
+		}
+
+		spin_unlock_bh(&target->rx_lock);
+
+		count--;
+
+		msleep_interruptible(HTC_TARGET_RESPONSE_POLL_WAIT);
+	}
+
+	if (count <= 0) {
+		ath6kl_dbg(ATH6KL_DBG_HTC, "%s: Timeout!\n", __func__);
+		return -ECOMM;
+	}
+
+	return 0;
+}
+
+static void htc_rxctrl_complete(struct htc_target *context,
+				struct htc_packet *packet)
+{
+	/* TODO, can't really receive HTC control messages yet.... */
+	ath6kl_dbg(ATH6KL_DBG_HTC, "%s: invalid call function\n", __func__);
+}
+
+/* htc pipe initialization */
+static void reset_endpoint_states(struct htc_target *target)
+{
+	struct htc_endpoint *ep;
+	int i;
+
+	for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
+		ep = &target->endpoint[i];
+		ep->svc_id = 0;
+		ep->len_max = 0;
+		ep->max_txq_depth = 0;
+		ep->eid = i;
+		INIT_LIST_HEAD(&ep->txq);
+		INIT_LIST_HEAD(&ep->pipe.tx_lookup_queue);
+		INIT_LIST_HEAD(&ep->rx_bufq);
+		ep->target = target;
+		ep->pipe.tx_credit_flow_enabled = (bool) 1; /* FIXME */
+	}
+}
+
+/* start HTC, this is called after all services are connected */
+static int htc_config_target_hif_pipe(struct htc_target *target)
+{
+	return 0;
+}
+
+/* htc service functions */
+static u8 htc_get_credit_alloc(struct htc_target *target, u16 service_id)
+{
+	u8 allocation = 0;
+	int i;
+
+	for (i = 0; i < ENDPOINT_MAX; i++) {
+		if (target->pipe.txcredit_alloc[i].service_id == service_id)
+			allocation =
+				target->pipe.txcredit_alloc[i].credit_alloc;
+	}
+
+	if (allocation == 0) {
+		ath6kl_dbg(ATH6KL_DBG_HTC,
+			   "HTC Service TX : 0x%2.2X : allocation is zero!\n",
+			   service_id);
+	}
+
+	return allocation;
+}
+
+static int ath6kl_htc_pipe_conn_service(struct htc_target *target,
+		     struct htc_service_connect_req *conn_req,
+		     struct htc_service_connect_resp *conn_resp)
+{
+	struct ath6kl *ar = target->dev->ar;
+	struct htc_packet *packet = NULL;
+	struct htc_conn_service_resp *resp_msg;
+	struct htc_conn_service_msg *conn_msg;
+	enum htc_endpoint_id assigned_epid = ENDPOINT_MAX;
+	bool disable_credit_flowctrl = false;
+	unsigned int max_msg_size = 0;
+	struct htc_endpoint *ep;
+	int length, status = 0;
+	struct sk_buff *skb;
+	u8 tx_alloc;
+	u16 flags;
+
+	if (conn_req->svc_id == 0) {
+		WARN_ON_ONCE(1);
+		status = -EINVAL;
+		goto free_packet;
+	}
+
+	if (conn_req->svc_id == HTC_CTRL_RSVD_SVC) {
+		/* special case for pseudo control service */
+		assigned_epid = ENDPOINT_0;
+		max_msg_size = HTC_MAX_CTRL_MSG_LEN;
+		tx_alloc = 0;
+
+	} else {
+
+		tx_alloc = htc_get_credit_alloc(target, conn_req->svc_id);
+		if (tx_alloc == 0) {
+			status = -ENOMEM;
+			goto free_packet;
+		}
+
+		/* allocate a packet to send to the target */
+		packet = htc_alloc_txctrl_packet(target);
+
+		if (packet == NULL) {
+			WARN_ON_ONCE(1);
+			status = -ENOMEM;
+			goto free_packet;
+		}
+
+		skb = packet->skb;
+		length = sizeof(struct htc_conn_service_msg);
+
+		/* assemble connect service message */
+		conn_msg = (struct htc_conn_service_msg *) skb_put(skb,
+								   length);
+		if (conn_msg == NULL) {
+			WARN_ON_ONCE(1);
+			status = -EINVAL;
+			goto free_packet;
+		}
+
+		memset(conn_msg, 0,
+		       sizeof(struct htc_conn_service_msg));
+		conn_msg->msg_id = cpu_to_le16(HTC_MSG_CONN_SVC_ID);
+		conn_msg->svc_id = cpu_to_le16(conn_req->svc_id);
+		conn_msg->conn_flags = cpu_to_le16(conn_req->conn_flags &
+					~HTC_CONN_FLGS_SET_RECV_ALLOC_MASK);
+
+		/* tell target desired recv alloc for this ep */
+		flags = tx_alloc << HTC_CONN_FLGS_SET_RECV_ALLOC_SHIFT;
+		conn_msg->conn_flags |= cpu_to_le16(flags);
+
+		if (conn_req->conn_flags &
+		    HTC_CONN_FLGS_DISABLE_CRED_FLOW_CTRL) {
+			disable_credit_flowctrl = true;
+		}
+
+		set_htc_pkt_info(packet, NULL, (u8 *) conn_msg,
+				 length,
+				 ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
+
+		status = ath6kl_htc_pipe_tx(target, packet);
+
+		/* we don't own it anymore */
+		packet = NULL;
+		if (status != 0)
+			goto free_packet;
+
+		/* wait for response */
+		status = htc_wait_recv_ctrl_message(target);
+		if (status != 0)
+			goto free_packet;
+
+		/* we controlled the buffer creation so it has to be
+		 * properly aligned
+		 */
+		resp_msg = (struct htc_conn_service_resp *)
+		    target->pipe.ctrl_response_buf;
+
+		if (resp_msg->msg_id != cpu_to_le16(HTC_MSG_CONN_SVC_RESP_ID) ||
+		    (target->pipe.ctrl_response_len < sizeof(*resp_msg))) {
+			/* this message is not valid */
+			WARN_ON_ONCE(1);
+			status = -EINVAL;
+			goto free_packet;
+		}
+
+		ath6kl_dbg(ATH6KL_DBG_TRC,
+			   "%s: service 0x%X conn resp: status: %d ep: %d\n",
+			   __func__, resp_msg->svc_id, resp_msg->status,
+			   resp_msg->eid);
+
+		conn_resp->resp_code = resp_msg->status;
+		/* check response status */
+		if (resp_msg->status != HTC_SERVICE_SUCCESS) {
+			ath6kl_dbg(ATH6KL_DBG_HTC,
+				   "Target failed service 0x%X connect request (status:%d)\n",
+				   resp_msg->svc_id, resp_msg->status);
+			status = -EINVAL;
+			goto free_packet;
+		}
+
+		assigned_epid = (enum htc_endpoint_id) resp_msg->eid;
+		max_msg_size = le16_to_cpu(resp_msg->max_msg_sz);
+	}
+
+	/* the rest are parameter checks so set the error status */
+	status = -EINVAL;
+
+	if (assigned_epid >= ENDPOINT_MAX) {
+		WARN_ON_ONCE(1);
+		goto free_packet;
+	}
+
+	if (max_msg_size == 0) {
+		WARN_ON_ONCE(1);
+		goto free_packet;
+	}
+
+	ep = &target->endpoint[assigned_epid];
+	ep->eid = assigned_epid;
+	if (ep->svc_id != 0) {
+		/* endpoint already in use! */
+		WARN_ON_ONCE(1);
+		goto free_packet;
+	}
+
+	/* return assigned endpoint to caller */
+	conn_resp->endpoint = assigned_epid;
+	conn_resp->len_max = max_msg_size;
+
+	/* setup the endpoint */
+	ep->svc_id = conn_req->svc_id; /* this marks ep in use */
+	ep->max_txq_depth = conn_req->max_txq_depth;
+	ep->len_max = max_msg_size;
+	ep->cred_dist.credits = tx_alloc;
+	ep->cred_dist.cred_sz = target->tgt_cred_sz;
+	ep->cred_dist.cred_per_msg = max_msg_size / target->tgt_cred_sz;
+	if (max_msg_size % target->tgt_cred_sz)
+		ep->cred_dist.cred_per_msg++;
+
+	/* copy all the callbacks */
+	ep->ep_cb = conn_req->ep_cb;
+
+	status = ath6kl_hif_pipe_map_service(ar, ep->svc_id,
+					     &ep->pipe.pipeid_ul,
+					     &ep->pipe.pipeid_dl);
+	if (status != 0)
+		goto free_packet;
+
+	ath6kl_dbg(ATH6KL_DBG_HTC,
+		   "SVC Ready: 0x%4.4X: ULpipe:%d DLpipe:%d id:%d\n",
+		   ep->svc_id, ep->pipe.pipeid_ul,
+		   ep->pipe.pipeid_dl, ep->eid);
+
+	if (disable_credit_flowctrl && ep->pipe.tx_credit_flow_enabled) {
+		ep->pipe.tx_credit_flow_enabled = false;
+		ath6kl_dbg(ATH6KL_DBG_HTC,
+			   "SVC: 0x%4.4X ep:%d TX flow control off\n",
+			   ep->svc_id, assigned_epid);
+	}
+
+free_packet:
+	if (packet != NULL)
+		htc_free_txctrl_packet(target, packet);
+	return status;
+}
+
+/* htc export functions */
+static void *ath6kl_htc_pipe_create(struct ath6kl *ar)
+{
+	int status = 0;
+	struct htc_endpoint *ep = NULL;
+	struct htc_target *target = NULL;
+	struct htc_packet *packet;
+	int i;
+
+	target = kzalloc(sizeof(struct htc_target), GFP_KERNEL);
+	if (target == NULL) {
+		ath6kl_err("htc create unable to allocate memory\n");
+		status = -ENOMEM;
+		goto fail_htc_create;
+	}
+
+	spin_lock_init(&target->htc_lock);
+	spin_lock_init(&target->rx_lock);
+	spin_lock_init(&target->tx_lock);
+
+	reset_endpoint_states(target);
+
+	for (i = 0; i < HTC_PACKET_CONTAINER_ALLOCATION; i++) {
+		packet = kzalloc(sizeof(struct htc_packet), GFP_KERNEL);
+
+		if (packet != NULL)
+			free_htc_packet_container(target, packet);
+	}
+
+	target->dev = kzalloc(sizeof(*target->dev), GFP_KERNEL);
+	if (!target->dev) {
+		ath6kl_err("unable to allocate memory\n");
+		status = -ENOMEM;
+		goto fail_htc_create;
+	}
+	target->dev->ar = ar;
+	target->dev->htc_cnxt = target;
+
+	/* Get HIF default pipe for HTC message exchange */
+	ep = &target->endpoint[ENDPOINT_0];
+
+	ath6kl_hif_pipe_get_default(ar, &ep->pipe.pipeid_ul,
+				    &ep->pipe.pipeid_dl);
+
+	return target;
+
+fail_htc_create:
+	if (status != 0) {
+		if (target != NULL)
+			ath6kl_htc_pipe_cleanup(target);
+
+		target = NULL;
+	}
+	return target;
+}
+
+/* cleanup the HTC instance */
+static void ath6kl_htc_pipe_cleanup(struct htc_target *target)
+{
+	struct htc_packet *packet;
+
+	while (true) {
+		packet = alloc_htc_packet_container(target);
+		if (packet == NULL)
+			break;
+		kfree(packet);
+	}
+
+	kfree(target->dev);
+
+	/* kfree our instance */
+	kfree(target);
+}
+
+static int ath6kl_htc_pipe_start(struct htc_target *target)
+{
+	struct sk_buff *skb;
+	struct htc_setup_comp_ext_msg *setup;
+	struct htc_packet *packet;
+
+	htc_config_target_hif_pipe(target);
+
+	/* allocate a buffer to send */
+	packet = htc_alloc_txctrl_packet(target);
+	if (packet == NULL) {
+		WARN_ON_ONCE(1);
+		return -ENOMEM;
+	}
+
+	skb = packet->skb;
+
+	/* assemble setup complete message */
+	setup = (struct htc_setup_comp_ext_msg *) skb_put(skb,
+							  sizeof(*setup));
+	memset(setup, 0, sizeof(struct htc_setup_comp_ext_msg));
+	setup->msg_id = cpu_to_le16(HTC_MSG_SETUP_COMPLETE_EX_ID);
+
+	ath6kl_dbg(ATH6KL_DBG_HTC, "HTC using TX credit flow control\n");
+
+	set_htc_pkt_info(packet, NULL, (u8 *) setup,
+			 sizeof(struct htc_setup_comp_ext_msg),
+			 ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
+
+	target->htc_flags |= HTC_OP_STATE_SETUP_COMPLETE;
+
+	return ath6kl_htc_pipe_tx(target, packet);
+}
+
+static void ath6kl_htc_pipe_stop(struct htc_target *target)
+{
+	int i;
+	struct htc_endpoint *ep;
+
+	/* cleanup endpoints */
+	for (i = 0; i < ENDPOINT_MAX; i++) {
+		ep = &target->endpoint[i];
+		htc_flush_rx_queue(target, ep);
+		htc_flush_tx_endpoint(target, ep, HTC_TX_PACKET_TAG_ALL);
+	}
+
+	reset_endpoint_states(target);
+	target->htc_flags &= ~HTC_OP_STATE_SETUP_COMPLETE;
+}
+
+static int ath6kl_htc_pipe_get_rxbuf_num(struct htc_target *target,
+					 enum htc_endpoint_id endpoint)
+{
+	int num;
+
+	spin_lock_bh(&target->rx_lock);
+	num = get_queue_depth(&(target->endpoint[endpoint].rx_bufq));
+	spin_unlock_bh(&target->rx_lock);
+
+	return num;
+}
+
+static int ath6kl_htc_pipe_tx(struct htc_target *target,
+			      struct htc_packet *packet)
+{
+	struct list_head queue;
+
+	ath6kl_dbg(ATH6KL_DBG_HTC,
+		   "%s: endPointId: %d, buffer: 0x%p, length: %d\n",
+		   __func__, packet->endpoint, packet->buf,
+		   packet->act_len);
+
+	INIT_LIST_HEAD(&queue);
+	list_add_tail(&packet->list, &queue);
+
+	return htc_send_packets_multiple(target, &queue);
+}
+
+static int ath6kl_htc_pipe_wait_target(struct htc_target *target)
+{
+	struct htc_ready_ext_msg *ready_msg;
+	struct htc_service_connect_req connect;
+	struct htc_service_connect_resp resp;
+	int status = 0;
+
+	status = htc_wait_recv_ctrl_message(target);
+
+	if (status != 0)
+		return status;
+
+	if (target->pipe.ctrl_response_len < sizeof(*ready_msg)) {
+		ath6kl_dbg(ATH6KL_DBG_HTC, "invalid htc ready msg len:%d!\n",
+			   target->pipe.ctrl_response_len);
+		return -ECOMM;
+	}
+
+	ready_msg = (struct htc_ready_ext_msg *) target->pipe.ctrl_response_buf;
+
+	if (ready_msg->ver2_0_info.msg_id != cpu_to_le16(HTC_MSG_READY_ID)) {
+		ath6kl_dbg(ATH6KL_DBG_HTC, "invalid htc ready msg : 0x%X !\n",
+			   ready_msg->ver2_0_info.msg_id);
+		return -ECOMM;
+	}
+
+	ath6kl_dbg(ATH6KL_DBG_HTC,
+		   "Target Ready! : transmit resources : %d size:%d\n",
+		   ready_msg->ver2_0_info.cred_cnt,
+		   ready_msg->ver2_0_info.cred_sz);
+
+	target->tgt_creds = le16_to_cpu(ready_msg->ver2_0_info.cred_cnt);
+	target->tgt_cred_sz = le16_to_cpu(ready_msg->ver2_0_info.cred_sz);
+
+	if ((target->tgt_creds == 0) || (target->tgt_cred_sz == 0))
+		return -ECOMM;
+
+	htc_setup_target_buffer_assignments(target);
+
+	/* setup our pseudo HTC control endpoint connection */
+	memset(&connect, 0, sizeof(connect));
+	memset(&resp, 0, sizeof(resp));
+	connect.ep_cb.tx_complete = htc_txctrl_complete;
+	connect.ep_cb.rx = htc_rxctrl_complete;
+	connect.max_txq_depth = NUM_CONTROL_TX_BUFFERS;
+	connect.svc_id = HTC_CTRL_RSVD_SVC;
+
+	/* connect fake service */
+	status = ath6kl_htc_pipe_conn_service(target, &connect, &resp);
+
+	return status;
+}
+
+static void ath6kl_htc_pipe_flush_txep(struct htc_target *target,
+				       enum htc_endpoint_id endpoint, u16 tag)
+{
+	struct htc_endpoint *ep = &target->endpoint[endpoint];
+
+	if (ep->svc_id == 0) {
+		WARN_ON_ONCE(1);
+		/* not in use.. */
+		return;
+	}
+
+	htc_flush_tx_endpoint(target, ep, tag);
+}
+
+static int ath6kl_htc_pipe_add_rxbuf_multiple(struct htc_target *target,
+					      struct list_head *pkt_queue)
+{
+	struct htc_packet *packet, *tmp_pkt, *first;
+	struct htc_endpoint *ep;
+	int status = 0;
+
+	if (list_empty(pkt_queue))
+		return -EINVAL;
+
+	first = list_first_entry(pkt_queue, struct htc_packet, list);
+	if (first == NULL) {
+		WARN_ON_ONCE(1);
+		return -EINVAL;
+	}
+
+	if (first->endpoint >= ENDPOINT_MAX) {
+		WARN_ON_ONCE(1);
+		return -EINVAL;
+	}
+
+	ath6kl_dbg(ATH6KL_DBG_HTC, "%s: epid: %d, cnt:%d, len: %d\n",
+		   __func__, first->endpoint, get_queue_depth(pkt_queue),
+		   first->buf_len);
+
+	ep = &target->endpoint[first->endpoint];
+
+	spin_lock_bh(&target->rx_lock);
+
+	/* store receive packets */
+	list_splice_tail_init(pkt_queue, &ep->rx_bufq);
+
+	spin_unlock_bh(&target->rx_lock);
+
+	if (status != 0) {
+		/* walk through queue and mark each one canceled */
+		list_for_each_entry_safe(packet, tmp_pkt, pkt_queue, list) {
+			packet->status = -ECANCELED;
+		}
+
+		do_recv_completion(ep, pkt_queue);
+	}
+
+	return status;
+}
+
+static void ath6kl_htc_pipe_activity_changed(struct htc_target *target,
+					     enum htc_endpoint_id ep,
+					     bool active)
+{
+	/* TODO */
+}
+
+static void ath6kl_htc_pipe_flush_rx_buf(struct htc_target *target)
+{
+	/* TODO */
+}
+
+static int ath6kl_htc_pipe_credit_setup(struct htc_target *target,
+					struct ath6kl_htc_credit_info *info)
+{
+	return 0;
+}
+
+static const struct ath6kl_htc_ops ath6kl_htc_pipe_ops = {
+	.create = ath6kl_htc_pipe_create,
+	.wait_target = ath6kl_htc_pipe_wait_target,
+	.start = ath6kl_htc_pipe_start,
+	.conn_service = ath6kl_htc_pipe_conn_service,
+	.tx = ath6kl_htc_pipe_tx,
+	.stop = ath6kl_htc_pipe_stop,
+	.cleanup = ath6kl_htc_pipe_cleanup,
+	.flush_txep = ath6kl_htc_pipe_flush_txep,
+	.flush_rx_buf = ath6kl_htc_pipe_flush_rx_buf,
+	.activity_changed = ath6kl_htc_pipe_activity_changed,
+	.get_rxbuf_num = ath6kl_htc_pipe_get_rxbuf_num,
+	.add_rxbuf_multiple = ath6kl_htc_pipe_add_rxbuf_multiple,
+	.credit_setup = ath6kl_htc_pipe_credit_setup,
+	.tx_complete = ath6kl_htc_pipe_tx_complete,
+	.rx_complete = ath6kl_htc_pipe_rx_complete,
+};
+
+void ath6kl_htc_pipe_attach(struct ath6kl *ar)
+{
+	ar->htc_ops = &ath6kl_htc_pipe_ops;
+}