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1/*
2 * Copyright (c) 2007-2011 Atheros Communications Inc.
3 *
4 * Permission to use, copy, modify, and/or distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 */
16
17#include "core.h"
18#include "debug.h"
19#include "hif-ops.h"
20
21#define HTC_PACKET_CONTAINER_ALLOCATION 32
22#define HTC_CONTROL_BUFFER_SIZE (HTC_MAX_CTRL_MSG_LEN + HTC_HDR_LENGTH)
23
24static int ath6kl_htc_pipe_tx(struct htc_target *handle,
25			      struct htc_packet *packet);
26static void ath6kl_htc_pipe_cleanup(struct htc_target *handle);
27
28/* htc pipe tx path */
29static inline void restore_tx_packet(struct htc_packet *packet)
30{
31	if (packet->info.tx.flags & HTC_FLAGS_TX_FIXUP_NETBUF) {
32		skb_pull(packet->skb, sizeof(struct htc_frame_hdr));
33		packet->info.tx.flags &= ~HTC_FLAGS_TX_FIXUP_NETBUF;
34	}
35}
36
37static void do_send_completion(struct htc_endpoint *ep,
38			       struct list_head *queue_to_indicate)
39{
40	struct htc_packet *packet;
41
42	if (list_empty(queue_to_indicate)) {
43		/* nothing to indicate */
44		return;
45	}
46
47	if (ep->ep_cb.tx_comp_multi != NULL) {
48		ath6kl_dbg(ATH6KL_DBG_HTC,
49			   "%s: calling ep %d, send complete multiple callback (%d pkts)\n",
50			   __func__, ep->eid,
51			   get_queue_depth(queue_to_indicate));
52		/*
53		 * a multiple send complete handler is being used,
54		 * pass the queue to the handler
55		 */
56		ep->ep_cb.tx_comp_multi(ep->target, queue_to_indicate);
57		/*
58		 * all packets are now owned by the callback,
59		 * reset queue to be safe
60		 */
61		INIT_LIST_HEAD(queue_to_indicate);
62	} else {
63		/* using legacy EpTxComplete */
64		do {
65			packet = list_first_entry(queue_to_indicate,
66						  struct htc_packet, list);
67
68			list_del(&packet->list);
69			ath6kl_dbg(ATH6KL_DBG_HTC,
70				   "%s: calling ep %d send complete callback on packet 0x%p\n",
71				   __func__, ep->eid, packet);
72			ep->ep_cb.tx_complete(ep->target, packet);
73		} while (!list_empty(queue_to_indicate));
74	}
75}
76
77static void send_packet_completion(struct htc_target *target,
78				   struct htc_packet *packet)
79{
80	struct htc_endpoint *ep = &target->endpoint[packet->endpoint];
81	struct list_head container;
82
83	restore_tx_packet(packet);
84	INIT_LIST_HEAD(&container);
85	list_add_tail(&packet->list, &container);
86
87	/* do completion */
88	do_send_completion(ep, &container);
89}
90
91static void get_htc_packet_credit_based(struct htc_target *target,
92					struct htc_endpoint *ep,
93					struct list_head *queue)
94{
95	int credits_required;
96	int remainder;
97	u8 send_flags;
98	struct htc_packet *packet;
99	unsigned int transfer_len;
100
101	/* NOTE : the TX lock is held when this function is called */
102
103	/* loop until we can grab as many packets out of the queue as we can */
104	while (true) {
105		send_flags = 0;
106		if (list_empty(&ep->txq))
107			break;
108
109		/* get packet at head, but don't remove it */
110		packet = list_first_entry(&ep->txq, struct htc_packet, list);
111
112		ath6kl_dbg(ATH6KL_DBG_HTC,
113			   "%s: got head packet:0x%p , queue depth: %d\n",
114			   __func__, packet, get_queue_depth(&ep->txq));
115
116		transfer_len = packet->act_len + HTC_HDR_LENGTH;
117
118		if (transfer_len <= target->tgt_cred_sz) {
119			credits_required = 1;
120		} else {
121			/* figure out how many credits this message requires */
122			credits_required = transfer_len / target->tgt_cred_sz;
123			remainder = transfer_len % target->tgt_cred_sz;
124
125			if (remainder)
126				credits_required++;
127		}
128
129		ath6kl_dbg(ATH6KL_DBG_HTC, "%s: creds required:%d got:%d\n",
130			   __func__, credits_required, ep->cred_dist.credits);
131
132		if (ep->eid == ENDPOINT_0) {
133			/*
134			 * endpoint 0 is special, it always has a credit and
135			 * does not require credit based flow control
136			 */
137			credits_required = 0;
138
139		} else {
140			if (ep->cred_dist.credits < credits_required)
141				break;
142
143			ep->cred_dist.credits -= credits_required;
144			ep->ep_st.cred_cosumd += credits_required;
145
146			/* check if we need credits back from the target */
147			if (ep->cred_dist.credits <
148					ep->cred_dist.cred_per_msg) {
149				/* tell the target we need credits ASAP! */
150				send_flags |= HTC_FLAGS_NEED_CREDIT_UPDATE;
151				ep->ep_st.cred_low_indicate += 1;
152				ath6kl_dbg(ATH6KL_DBG_HTC,
153					   "%s: host needs credits\n",
154					   __func__);
155			}
156		}
157
158		/* now we can fully dequeue */
159		packet = list_first_entry(&ep->txq, struct htc_packet, list);
160
161		list_del(&packet->list);
162		/* save the number of credits this packet consumed */
163		packet->info.tx.cred_used = credits_required;
164		/* save send flags */
165		packet->info.tx.flags = send_flags;
166		packet->info.tx.seqno = ep->seqno;
167		ep->seqno++;
168		/* queue this packet into the caller's queue */
169		list_add_tail(&packet->list, queue);
170	}
171}
172
173static void get_htc_packet(struct htc_target *target,
174			   struct htc_endpoint *ep,
175			   struct list_head *queue, int resources)
176{
177	struct htc_packet *packet;
178
179	/* NOTE : the TX lock is held when this function is called */
180
181	/* loop until we can grab as many packets out of the queue as we can */
182	while (resources) {
183		if (list_empty(&ep->txq))
184			break;
185
186		packet = list_first_entry(&ep->txq, struct htc_packet, list);
187		list_del(&packet->list);
188
189		ath6kl_dbg(ATH6KL_DBG_HTC,
190			   "%s: got packet:0x%p , new queue depth: %d\n",
191			   __func__, packet, get_queue_depth(&ep->txq));
192		packet->info.tx.seqno = ep->seqno;
193		packet->info.tx.flags = 0;
194		packet->info.tx.cred_used = 0;
195		ep->seqno++;
196
197		/* queue this packet into the caller's queue */
198		list_add_tail(&packet->list, queue);
199		resources--;
200	}
201}
202
203static int htc_issue_packets(struct htc_target *target,
204			     struct htc_endpoint *ep,
205			     struct list_head *pkt_queue)
206{
207	int status = 0;
208	u16 payload_len;
209	struct sk_buff *skb;
210	struct htc_frame_hdr *htc_hdr;
211	struct htc_packet *packet;
212
213	ath6kl_dbg(ATH6KL_DBG_HTC,
214		   "%s: queue: 0x%p, pkts %d\n", __func__,
215		   pkt_queue, get_queue_depth(pkt_queue));
216
217	while (!list_empty(pkt_queue)) {
218		packet = list_first_entry(pkt_queue, struct htc_packet, list);
219		list_del(&packet->list);
220
221		skb = packet->skb;
222		if (!skb) {
223			WARN_ON_ONCE(1);
224			status = -EINVAL;
225			break;
226		}
227
228		payload_len = packet->act_len;
229
230		/* setup HTC frame header */
231		htc_hdr = (struct htc_frame_hdr *) skb_push(skb,
232							    sizeof(*htc_hdr));
233		if (!htc_hdr) {
234			WARN_ON_ONCE(1);
235			status = -EINVAL;
236			break;
237		}
238
239		packet->info.tx.flags |= HTC_FLAGS_TX_FIXUP_NETBUF;
240
241		/* Endianess? */
242		put_unaligned((u16) payload_len, &htc_hdr->payld_len);
243		htc_hdr->flags = packet->info.tx.flags;
244		htc_hdr->eid = (u8) packet->endpoint;
245		htc_hdr->ctrl[0] = 0;
246		htc_hdr->ctrl[1] = (u8) packet->info.tx.seqno;
247
248		spin_lock_bh(&target->tx_lock);
249
250		/* store in look up queue to match completions */
251		list_add_tail(&packet->list, &ep->pipe.tx_lookup_queue);
252		ep->ep_st.tx_issued += 1;
253		spin_unlock_bh(&target->tx_lock);
254
255		status = ath6kl_hif_pipe_send(target->dev->ar,
256					      ep->pipe.pipeid_ul, NULL, skb);
257
258		if (status != 0) {
259			if (status != -ENOMEM) {
260				/* TODO: if more than 1 endpoint maps to the
261				 * same PipeID, it is possible to run out of
262				 * resources in the HIF layer.
263				 * Don't emit the error
264				 */
265				ath6kl_dbg(ATH6KL_DBG_HTC,
266					   "%s: failed status:%d\n",
267					   __func__, status);
268			}
269			spin_lock_bh(&target->tx_lock);
270			list_del(&packet->list);
271
272			/* reclaim credits */
273			ep->cred_dist.credits += packet->info.tx.cred_used;
274			spin_unlock_bh(&target->tx_lock);
275
276			/* put it back into the callers queue */
277			list_add(&packet->list, pkt_queue);
278			break;
279		}
280	}
281
282	if (status != 0) {
283		while (!list_empty(pkt_queue)) {
284			if (status != -ENOMEM) {
285				ath6kl_dbg(ATH6KL_DBG_HTC,
286					   "%s: failed pkt:0x%p status:%d\n",
287					   __func__, packet, status);
288			}
289
290			packet = list_first_entry(pkt_queue,
291						  struct htc_packet, list);
292			list_del(&packet->list);
293			packet->status = status;
294			send_packet_completion(target, packet);
295		}
296	}
297
298	return status;
299}
300
301static enum htc_send_queue_result htc_try_send(struct htc_target *target,
302					       struct htc_endpoint *ep,
303					       struct list_head *txq)
304{
305	struct list_head send_queue;	/* temp queue to hold packets */
306	struct htc_packet *packet, *tmp_pkt;
307	struct ath6kl *ar = target->dev->ar;
308	enum htc_send_full_action action;
309	int tx_resources, overflow, txqueue_depth, i, good_pkts;
310	u8 pipeid;
311
312	ath6kl_dbg(ATH6KL_DBG_HTC, "%s: (queue:0x%p depth:%d)\n",
313		   __func__, txq,
314		   (txq == NULL) ? 0 : get_queue_depth(txq));
315
316	/* init the local send queue */
317	INIT_LIST_HEAD(&send_queue);
318
319	/*
320	 * txq equals to NULL means
321	 * caller didn't provide a queue, just wants us to
322	 * check queues and send
323	 */
324	if (txq != NULL) {
325		if (list_empty(txq)) {
326			/* empty queue */
327			return HTC_SEND_QUEUE_DROP;
328		}
329
330		spin_lock_bh(&target->tx_lock);
331		txqueue_depth = get_queue_depth(&ep->txq);
332		spin_unlock_bh(&target->tx_lock);
333
334		if (txqueue_depth >= ep->max_txq_depth) {
335			/* we've already overflowed */
336			overflow = get_queue_depth(txq);
337		} else {
338			/* get how much we will overflow by */
339			overflow = txqueue_depth;
340			overflow += get_queue_depth(txq);
341			/* get how much we will overflow the TX queue by */
342			overflow -= ep->max_txq_depth;
343		}
344
345		/* if overflow is negative or zero, we are okay */
346		if (overflow > 0) {
347			ath6kl_dbg(ATH6KL_DBG_HTC,
348				   "%s: Endpoint %d, TX queue will overflow :%d, Tx Depth:%d, Max:%d\n",
349				   __func__, ep->eid, overflow, txqueue_depth,
350				   ep->max_txq_depth);
351		}
352		if ((overflow <= 0) ||
353		    (ep->ep_cb.tx_full == NULL)) {
354			/*
355			 * all packets will fit or caller did not provide send
356			 * full indication handler -- just move all of them
357			 * to the local send_queue object
358			 */
359			list_splice_tail_init(txq, &send_queue);
360		} else {
361			good_pkts = get_queue_depth(txq) - overflow;
362			if (good_pkts < 0) {
363				WARN_ON_ONCE(1);
364				return HTC_SEND_QUEUE_DROP;
365			}
366
367			/* we have overflowed, and a callback is provided */
368			/* dequeue all non-overflow packets to the sendqueue */
369			for (i = 0; i < good_pkts; i++) {
370				/* pop off caller's queue */
371				packet = list_first_entry(txq,
372							  struct htc_packet,
373							  list);
374				/* move to local queue */
375				list_move_tail(&packet->list, &send_queue);
376			}
377
378			/*
379			 * the caller's queue has all the packets that won't fit
380			 * walk through the caller's queue and indicate each to
381			 * the send full handler
382			 */
383			list_for_each_entry_safe(packet, tmp_pkt,
384						 txq, list) {
385				ath6kl_dbg(ATH6KL_DBG_HTC,
386					   "%s: Indicat overflowed TX pkts: %p\n",
387					   __func__, packet);
388				action = ep->ep_cb.tx_full(ep->target, packet);
389				if (action == HTC_SEND_FULL_DROP) {
390					/* callback wants the packet dropped */
391					ep->ep_st.tx_dropped += 1;
392
393					/* leave this one in the caller's queue
394					 * for cleanup */
395				} else {
396					/* callback wants to keep this packet,
397					 * move from caller's queue to the send
398					 * queue */
399					list_move_tail(&packet->list,
400						       &send_queue);
401				}
402			}
403
404			if (list_empty(&send_queue)) {
405				/* no packets made it in, caller will cleanup */
406				return HTC_SEND_QUEUE_DROP;
407			}
408		}
409	}
410
411	if (!ep->pipe.tx_credit_flow_enabled) {
412		tx_resources =
413		    ath6kl_hif_pipe_get_free_queue_number(ar,
414							  ep->pipe.pipeid_ul);
415	} else {
416		tx_resources = 0;
417	}
418
419	spin_lock_bh(&target->tx_lock);
420	if (!list_empty(&send_queue)) {
421		/* transfer packets to tail */
422		list_splice_tail_init(&send_queue, &ep->txq);
423		if (!list_empty(&send_queue)) {
424			WARN_ON_ONCE(1);
425			spin_unlock_bh(&target->tx_lock);
426			return HTC_SEND_QUEUE_DROP;
427		}
428		INIT_LIST_HEAD(&send_queue);
429	}
430
431	/* increment tx processing count on entry */
432	ep->tx_proc_cnt++;
433
434	if (ep->tx_proc_cnt > 1) {
435		/*
436		 * Another thread or task is draining the TX queues on this
437		 * endpoint that thread will reset the tx processing count
438		 * when the queue is drained.
439		 */
440		ep->tx_proc_cnt--;
441		spin_unlock_bh(&target->tx_lock);
442		return HTC_SEND_QUEUE_OK;
443	}
444
445	/***** beyond this point only 1 thread may enter ******/
446
447	/*
448	 * Now drain the endpoint TX queue for transmission as long as we have
449	 * enough transmit resources.
450	 */
451	while (true) {
452		if (get_queue_depth(&ep->txq) == 0)
453			break;
454
455		if (ep->pipe.tx_credit_flow_enabled) {
456			/*
457			 * Credit based mechanism provides flow control
458			 * based on target transmit resource availability,
459			 * we assume that the HIF layer will always have
460			 * bus resources greater than target transmit
461			 * resources.
462			 */
463			get_htc_packet_credit_based(target, ep, &send_queue);
464		} else {
465			/*
466			 * Get all packets for this endpoint that we can
467			 * for this pass.
468			 */
469			get_htc_packet(target, ep, &send_queue, tx_resources);
470		}
471
472		if (get_queue_depth(&send_queue) == 0) {
473			/*
474			 * Didn't get packets due to out of resources or TX
475			 * queue was drained.
476			 */
477			break;
478		}
479
480		spin_unlock_bh(&target->tx_lock);
481
482		/* send what we can */
483		htc_issue_packets(target, ep, &send_queue);
484
485		if (!ep->pipe.tx_credit_flow_enabled) {
486			pipeid = ep->pipe.pipeid_ul;
487			tx_resources =
488			    ath6kl_hif_pipe_get_free_queue_number(ar, pipeid);
489		}
490
491		spin_lock_bh(&target->tx_lock);
492	}
493
494	/* done with this endpoint, we can clear the count */
495	ep->tx_proc_cnt = 0;
496	spin_unlock_bh(&target->tx_lock);
497
498	return HTC_SEND_QUEUE_OK;
499}
500
501/* htc control packet manipulation */
502static void destroy_htc_txctrl_packet(struct htc_packet *packet)
503{
504	struct sk_buff *skb;
505	skb = packet->skb;
506	dev_kfree_skb(skb);
507	kfree(packet);
508}
509
510static struct htc_packet *build_htc_txctrl_packet(void)
511{
512	struct htc_packet *packet = NULL;
513	struct sk_buff *skb;
514
515	packet = kzalloc(sizeof(struct htc_packet), GFP_KERNEL);
516	if (packet == NULL)
517		return NULL;
518
519	skb = __dev_alloc_skb(HTC_CONTROL_BUFFER_SIZE, GFP_KERNEL);
520
521	if (skb == NULL) {
522		kfree(packet);
523		return NULL;
524	}
525	packet->skb = skb;
526
527	return packet;
528}
529
530static void htc_free_txctrl_packet(struct htc_target *target,
531				   struct htc_packet *packet)
532{
533	destroy_htc_txctrl_packet(packet);
534}
535
536static struct htc_packet *htc_alloc_txctrl_packet(struct htc_target *target)
537{
538	return build_htc_txctrl_packet();
539}
540
541static void htc_txctrl_complete(struct htc_target *target,
542				struct htc_packet *packet)
543{
544	htc_free_txctrl_packet(target, packet);
545}
546
547#define MAX_MESSAGE_SIZE 1536
548
549static int htc_setup_target_buffer_assignments(struct htc_target *target)
550{
551	int status, credits, credit_per_maxmsg, i;
552	struct htc_pipe_txcredit_alloc *entry;
553	unsigned int hif_usbaudioclass = 0;
554
555	credit_per_maxmsg = MAX_MESSAGE_SIZE / target->tgt_cred_sz;
556	if (MAX_MESSAGE_SIZE % target->tgt_cred_sz)
557		credit_per_maxmsg++;
558
559	/* TODO, this should be configured by the caller! */
560
561	credits = target->tgt_creds;
562	entry = &target->pipe.txcredit_alloc[0];
563
564	status = -ENOMEM;
565
566	/* FIXME: hif_usbaudioclass is always zero */
567	if (hif_usbaudioclass) {
568		ath6kl_dbg(ATH6KL_DBG_HTC,
569			   "%s: For USB Audio Class- Total:%d\n",
570			   __func__, credits);
571		entry++;
572		entry++;
573		/* Setup VO Service To have Max Credits */
574		entry->service_id = WMI_DATA_VO_SVC;
575		entry->credit_alloc = (credits - 6);
576		if (entry->credit_alloc == 0)
577			entry->credit_alloc++;
578
579		credits -= (int) entry->credit_alloc;
580		if (credits <= 0)
581			return status;
582
583		entry++;
584		entry->service_id = WMI_CONTROL_SVC;
585		entry->credit_alloc = credit_per_maxmsg;
586		credits -= (int) entry->credit_alloc;
587		if (credits <= 0)
588			return status;
589
590		/* leftovers go to best effort */
591		entry++;
592		entry++;
593		entry->service_id = WMI_DATA_BE_SVC;
594		entry->credit_alloc = (u8) credits;
595		status = 0;
596	} else {
597		entry++;
598		entry->service_id = WMI_DATA_VI_SVC;
599		entry->credit_alloc = credits / 4;
600		if (entry->credit_alloc == 0)
601			entry->credit_alloc++;
602
603		credits -= (int) entry->credit_alloc;
604		if (credits <= 0)
605			return status;
606
607		entry++;
608		entry->service_id = WMI_DATA_VO_SVC;
609		entry->credit_alloc = credits / 4;
610		if (entry->credit_alloc == 0)
611			entry->credit_alloc++;
612
613		credits -= (int) entry->credit_alloc;
614		if (credits <= 0)
615			return status;
616
617		entry++;
618		entry->service_id = WMI_CONTROL_SVC;
619		entry->credit_alloc = credit_per_maxmsg;
620		credits -= (int) entry->credit_alloc;
621		if (credits <= 0)
622			return status;
623
624		entry++;
625		entry->service_id = WMI_DATA_BK_SVC;
626		entry->credit_alloc = credit_per_maxmsg;
627		credits -= (int) entry->credit_alloc;
628		if (credits <= 0)
629			return status;
630
631		/* leftovers go to best effort */
632		entry++;
633		entry->service_id = WMI_DATA_BE_SVC;
634		entry->credit_alloc = (u8) credits;
635		status = 0;
636	}
637
638	if (status == 0) {
639		for (i = 0; i < ENDPOINT_MAX; i++) {
640			if (target->pipe.txcredit_alloc[i].service_id != 0) {
641				ath6kl_dbg(ATH6KL_DBG_HTC,
642					   "HTC Service Index : %d TX : 0x%2.2X : alloc:%d\n",
643					   i,
644					   target->pipe.txcredit_alloc[i].
645					   service_id,
646					   target->pipe.txcredit_alloc[i].
647					   credit_alloc);
648			}
649		}
650	}
651	return status;
652}
653
654/* process credit reports and call distribution function */
655static void htc_process_credit_report(struct htc_target *target,
656				      struct htc_credit_report *rpt,
657				      int num_entries,
658				      enum htc_endpoint_id from_ep)
659{
660	int total_credits = 0, i;
661	struct htc_endpoint *ep;
662
663	/* lock out TX while we update credits */
664	spin_lock_bh(&target->tx_lock);
665
666	for (i = 0; i < num_entries; i++, rpt++) {
667		if (rpt->eid >= ENDPOINT_MAX) {
668			WARN_ON_ONCE(1);
669			spin_unlock_bh(&target->tx_lock);
670			return;
671		}
672
673		ep = &target->endpoint[rpt->eid];
674		ep->cred_dist.credits += rpt->credits;
675
676		if (ep->cred_dist.credits && get_queue_depth(&ep->txq)) {
677			spin_unlock_bh(&target->tx_lock);
678			htc_try_send(target, ep, NULL);
679			spin_lock_bh(&target->tx_lock);
680		}
681
682		total_credits += rpt->credits;
683	}
684	ath6kl_dbg(ATH6KL_DBG_HTC,
685		   "Report indicated %d credits to distribute\n",
686		   total_credits);
687
688	spin_unlock_bh(&target->tx_lock);
689}
690
691/* flush endpoint TX queue */
692static void htc_flush_tx_endpoint(struct htc_target *target,
693				  struct htc_endpoint *ep, u16 tag)
694{
695	struct htc_packet *packet;
696
697	spin_lock_bh(&target->tx_lock);
698	while (get_queue_depth(&ep->txq)) {
699		packet = list_first_entry(&ep->txq, struct htc_packet, list);
700		list_del(&packet->list);
701		packet->status = 0;
702		send_packet_completion(target, packet);
703	}
704	spin_unlock_bh(&target->tx_lock);
705}
706
707/*
708 * In the adapted HIF layer, struct sk_buff * are passed between HIF and HTC,
709 * since upper layers expects struct htc_packet containers we use the completed
710 * skb and lookup it's corresponding HTC packet buffer from a lookup list.
711 * This is extra overhead that can be fixed by re-aligning HIF interfaces with
712 * HTC.
713 */
714static struct htc_packet *htc_lookup_tx_packet(struct htc_target *target,
715					       struct htc_endpoint *ep,
716					       struct sk_buff *skb)
717{
718	struct htc_packet *packet, *tmp_pkt, *found_packet = NULL;
719
720	spin_lock_bh(&target->tx_lock);
721
722	/*
723	 * interate from the front of tx lookup queue
724	 * this lookup should be fast since lower layers completes in-order and
725	 * so the completed packet should be at the head of the list generally
726	 */
727	list_for_each_entry_safe(packet, tmp_pkt, &ep->pipe.tx_lookup_queue,
728				 list) {
729		/* check for removal */
730		if (skb == packet->skb) {
731			/* found it */
732			list_del(&packet->list);
733			found_packet = packet;
734			break;
735		}
736	}
737
738	spin_unlock_bh(&target->tx_lock);
739
740	return found_packet;
741}
742
743static int ath6kl_htc_pipe_tx_complete(struct ath6kl *ar, struct sk_buff *skb)
744{
745	struct htc_target *target = ar->htc_target;
746	struct htc_frame_hdr *htc_hdr;
747	struct htc_endpoint *ep;
748	struct htc_packet *packet;
749	u8 ep_id, *netdata;
750	u32 netlen;
751
752	netdata = skb->data;
753	netlen = skb->len;
754
755	htc_hdr = (struct htc_frame_hdr *) netdata;
756
757	ep_id = htc_hdr->eid;
758	ep = &target->endpoint[ep_id];
759
760	packet = htc_lookup_tx_packet(target, ep, skb);
761	if (packet == NULL) {
762		/* may have already been flushed and freed */
763		ath6kl_err("HTC TX lookup failed!\n");
764	} else {
765		/* will be giving this buffer back to upper layers */
766		packet->status = 0;
767		send_packet_completion(target, packet);
768	}
769	skb = NULL;
770
771	if (!ep->pipe.tx_credit_flow_enabled) {
772		/*
773		 * note: when using TX credit flow, the re-checking of queues
774		 * happens when credits flow back from the target. in the
775		 * non-TX credit case, we recheck after the packet completes
776		 */
777		htc_try_send(target, ep, NULL);
778	}
779
780	return 0;
781}
782
783static int htc_send_packets_multiple(struct htc_target *target,
784				     struct list_head *pkt_queue)
785{
786	struct htc_endpoint *ep;
787	struct htc_packet *packet, *tmp_pkt;
788
789	if (list_empty(pkt_queue))
790		return -EINVAL;
791
792	/* get first packet to find out which ep the packets will go into */
793	packet = list_first_entry(pkt_queue, struct htc_packet, list);
794
795	if (packet->endpoint >= ENDPOINT_MAX) {
796		WARN_ON_ONCE(1);
797		return -EINVAL;
798	}
799	ep = &target->endpoint[packet->endpoint];
800
801	htc_try_send(target, ep, pkt_queue);
802
803	/* do completion on any packets that couldn't get in */
804	if (!list_empty(pkt_queue)) {
805		list_for_each_entry_safe(packet, tmp_pkt, pkt_queue, list) {
806			packet->status = -ENOMEM;
807		}
808
809		do_send_completion(ep, pkt_queue);
810	}
811
812	return 0;
813}
814
815/* htc pipe rx path */
816static struct htc_packet *alloc_htc_packet_container(struct htc_target *target)
817{
818	struct htc_packet *packet;
819	spin_lock_bh(&target->rx_lock);
820
821	if (target->pipe.htc_packet_pool == NULL) {
822		spin_unlock_bh(&target->rx_lock);
823		return NULL;
824	}
825
826	packet = target->pipe.htc_packet_pool;
827	target->pipe.htc_packet_pool = (struct htc_packet *) packet->list.next;
828
829	spin_unlock_bh(&target->rx_lock);
830
831	packet->list.next = NULL;
832	return packet;
833}
834
835static void free_htc_packet_container(struct htc_target *target,
836				      struct htc_packet *packet)
837{
838	struct list_head *lh;
839
840	spin_lock_bh(&target->rx_lock);
841
842	if (target->pipe.htc_packet_pool == NULL) {
843		target->pipe.htc_packet_pool = packet;
844		packet->list.next = NULL;
845	} else {
846		lh = (struct list_head *) target->pipe.htc_packet_pool;
847		packet->list.next = lh;
848		target->pipe.htc_packet_pool = packet;
849	}
850
851	spin_unlock_bh(&target->rx_lock);
852}
853
854static int htc_process_trailer(struct htc_target *target, u8 *buffer,
855			       int len, enum htc_endpoint_id from_ep)
856{
857	struct htc_credit_report *report;
858	struct htc_record_hdr *record;
859	u8 *record_buf, *orig_buf;
860	int orig_len, status;
861
862	orig_buf = buffer;
863	orig_len = len;
864	status = 0;
865
866	while (len > 0) {
867		if (len < sizeof(struct htc_record_hdr)) {
868			status = -EINVAL;
869			break;
870		}
871
872		/* these are byte aligned structs */
873		record = (struct htc_record_hdr *) buffer;
874		len -= sizeof(struct htc_record_hdr);
875		buffer += sizeof(struct htc_record_hdr);
876
877		if (record->len > len) {
878			/* no room left in buffer for record */
879			ath6kl_dbg(ATH6KL_DBG_HTC,
880				   "invalid length: %d (id:%d) buffer has: %d bytes left\n",
881				   record->len, record->rec_id, len);
882			status = -EINVAL;
883			break;
884		}
885
886		/* start of record follows the header */
887		record_buf = buffer;
888
889		switch (record->rec_id) {
890		case HTC_RECORD_CREDITS:
891			if (record->len < sizeof(struct htc_credit_report)) {
892				WARN_ON_ONCE(1);
893				return -EINVAL;
894			}
895
896			report = (struct htc_credit_report *) record_buf;
897			htc_process_credit_report(target, report,
898						  record->len / sizeof(*report),
899						  from_ep);
900			break;
901		default:
902			ath6kl_dbg(ATH6KL_DBG_HTC,
903				   "unhandled record: id:%d length:%d\n",
904				   record->rec_id, record->len);
905			break;
906		}
907
908		if (status != 0)
909			break;
910
911		/* advance buffer past this record for next time around */
912		buffer += record->len;
913		len -= record->len;
914	}
915
916	return status;
917}
918
919static void do_recv_completion(struct htc_endpoint *ep,
920			       struct list_head *queue_to_indicate)
921{
922	struct htc_packet *packet;
923
924	if (list_empty(queue_to_indicate)) {
925		/* nothing to indicate */
926		return;
927	}
928
929	/* using legacy EpRecv */
930	while (!list_empty(queue_to_indicate)) {
931		packet = list_first_entry(queue_to_indicate,
932					  struct htc_packet, list);
933		list_del(&packet->list);
934		ep->ep_cb.rx(ep->target, packet);
935	}
936
937	return;
938}
939
940static void recv_packet_completion(struct htc_target *target,
941				   struct htc_endpoint *ep,
942				   struct htc_packet *packet)
943{
944	struct list_head container;
945	INIT_LIST_HEAD(&container);
946	list_add_tail(&packet->list, &container);
947
948	/* do completion */
949	do_recv_completion(ep, &container);
950}
951
952static int ath6kl_htc_pipe_rx_complete(struct ath6kl *ar, struct sk_buff *skb,
953				       u8 pipeid)
954{
955	struct htc_target *target = ar->htc_target;
956	u8 *netdata, *trailer, hdr_info;
957	struct htc_frame_hdr *htc_hdr;
958	u32 netlen, trailerlen = 0;
959	struct htc_packet *packet;
960	struct htc_endpoint *ep;
961	u16 payload_len;
962	int status = 0;
963
964	/*
965	 * ar->htc_target can be NULL due to a race condition that can occur
966	 * during driver initialization(we do 'ath6kl_hif_power_on' before
967	 * initializing 'ar->htc_target' via 'ath6kl_htc_create').
968	 * 'ath6kl_hif_power_on' assigns 'ath6kl_recv_complete' as
969	 * usb_complete_t/callback function for 'usb_fill_bulk_urb'.
970	 * Thus the possibility of ar->htc_target being NULL
971	 * via ath6kl_recv_complete -> ath6kl_usb_io_comp_work.
972	 */
973	if (WARN_ON_ONCE(!target)) {
974		ath6kl_err("Target not yet initialized\n");
975		status = -EINVAL;
976		goto free_skb;
977	}
978
979
980	netdata = skb->data;
981	netlen = skb->len;
982
983	htc_hdr = (struct htc_frame_hdr *) netdata;
984
985	if (htc_hdr->eid >= ENDPOINT_MAX) {
986		ath6kl_dbg(ATH6KL_DBG_HTC,
987			   "HTC Rx: invalid EndpointID=%d\n",
988			   htc_hdr->eid);
989		status = -EINVAL;
990		goto free_skb;
991	}
992	ep = &target->endpoint[htc_hdr->eid];
993
994	payload_len = le16_to_cpu(get_unaligned(&htc_hdr->payld_len));
995
996	if (netlen < (payload_len + HTC_HDR_LENGTH)) {
997		ath6kl_dbg(ATH6KL_DBG_HTC,
998			   "HTC Rx: insufficient length, got:%d expected =%u\n",
999			   netlen, payload_len + HTC_HDR_LENGTH);
1000		status = -EINVAL;
1001		goto free_skb;
1002	}
1003
1004	/* get flags to check for trailer */
1005	hdr_info = htc_hdr->flags;
1006	if (hdr_info & HTC_FLG_RX_TRAILER) {
1007		/* extract the trailer length */
1008		hdr_info = htc_hdr->ctrl[0];
1009		if ((hdr_info < sizeof(struct htc_record_hdr)) ||
1010		    (hdr_info > payload_len)) {
1011			ath6kl_dbg(ATH6KL_DBG_HTC,
1012				   "invalid header: payloadlen should be %d, CB[0]: %d\n",
1013				   payload_len, hdr_info);
1014			status = -EINVAL;
1015			goto free_skb;
1016		}
1017
1018		trailerlen = hdr_info;
1019		/* process trailer after hdr/apps payload */
1020		trailer = (u8 *) htc_hdr + HTC_HDR_LENGTH +
1021			payload_len - hdr_info;
1022		status = htc_process_trailer(target, trailer, hdr_info,
1023					     htc_hdr->eid);
1024		if (status != 0)
1025			goto free_skb;
1026	}
1027
1028	if (((int) payload_len - (int) trailerlen) <= 0) {
1029		/* zero length packet with trailer, just drop these */
1030		goto free_skb;
1031	}
1032
1033	if (htc_hdr->eid == ENDPOINT_0) {
1034		/* handle HTC control message */
1035		if (target->htc_flags & HTC_OP_STATE_SETUP_COMPLETE) {
1036			/*
1037			 * fatal: target should not send unsolicited
1038			 * messageson the endpoint 0
1039			 */
1040			ath6kl_dbg(ATH6KL_DBG_HTC,
1041				   "HTC ignores Rx Ctrl after setup complete\n");
1042			status = -EINVAL;
1043			goto free_skb;
1044		}
1045
1046		/* remove HTC header */
1047		skb_pull(skb, HTC_HDR_LENGTH);
1048
1049		netdata = skb->data;
1050		netlen = skb->len;
1051
1052		spin_lock_bh(&target->rx_lock);
1053
1054		target->pipe.ctrl_response_valid = true;
1055		target->pipe.ctrl_response_len = min_t(int, netlen,
1056						       HTC_MAX_CTRL_MSG_LEN);
1057		memcpy(target->pipe.ctrl_response_buf, netdata,
1058		       target->pipe.ctrl_response_len);
1059
1060		spin_unlock_bh(&target->rx_lock);
1061
1062		dev_kfree_skb(skb);
1063		skb = NULL;
1064
1065		goto free_skb;
1066	}
1067
1068	/*
1069	 * TODO: the message based HIF architecture allocates net bufs
1070	 * for recv packets since it bridges that HIF to upper layers,
1071	 * which expects HTC packets, we form the packets here
1072	 */
1073	packet = alloc_htc_packet_container(target);
1074	if (packet == NULL) {
1075		status = -ENOMEM;
1076		goto free_skb;
1077	}
1078
1079	packet->status = 0;
1080	packet->endpoint = htc_hdr->eid;
1081	packet->pkt_cntxt = skb;
1082
1083	/* TODO: for backwards compatibility */
1084	packet->buf = skb_push(skb, 0) + HTC_HDR_LENGTH;
1085	packet->act_len = netlen - HTC_HDR_LENGTH - trailerlen;
1086
1087	/*
1088	 * TODO: this is a hack because the driver layer will set the
1089	 * actual len of the skb again which will just double the len
1090	 */
1091	skb_trim(skb, 0);
1092
1093	recv_packet_completion(target, ep, packet);
1094
1095	/* recover the packet container */
1096	free_htc_packet_container(target, packet);
1097	skb = NULL;
1098
1099free_skb:
1100	dev_kfree_skb(skb);
1101
1102	return status;
1103}
1104
1105static void htc_flush_rx_queue(struct htc_target *target,
1106			       struct htc_endpoint *ep)
1107{
1108	struct list_head container;
1109	struct htc_packet *packet;
1110
1111	spin_lock_bh(&target->rx_lock);
1112
1113	while (1) {
1114		if (list_empty(&ep->rx_bufq))
1115			break;
1116
1117		packet = list_first_entry(&ep->rx_bufq,
1118					  struct htc_packet, list);
1119		list_del(&packet->list);
1120
1121		spin_unlock_bh(&target->rx_lock);
1122		packet->status = -ECANCELED;
1123		packet->act_len = 0;
1124
1125		ath6kl_dbg(ATH6KL_DBG_HTC,
1126			   "Flushing RX packet:0x%p, length:%d, ep:%d\n",
1127			   packet, packet->buf_len,
1128			   packet->endpoint);
1129
1130		INIT_LIST_HEAD(&container);
1131		list_add_tail(&packet->list, &container);
1132
1133		/* give the packet back */
1134		do_recv_completion(ep, &container);
1135		spin_lock_bh(&target->rx_lock);
1136	}
1137
1138	spin_unlock_bh(&target->rx_lock);
1139}
1140
1141/* polling routine to wait for a control packet to be received */
1142static int htc_wait_recv_ctrl_message(struct htc_target *target)
1143{
1144	int count = HTC_TARGET_RESPONSE_POLL_COUNT;
1145
1146	while (count > 0) {
1147		spin_lock_bh(&target->rx_lock);
1148
1149		if (target->pipe.ctrl_response_valid) {
1150			target->pipe.ctrl_response_valid = false;
1151			spin_unlock_bh(&target->rx_lock);
1152			break;
1153		}
1154
1155		spin_unlock_bh(&target->rx_lock);
1156
1157		count--;
1158
1159		msleep_interruptible(HTC_TARGET_RESPONSE_POLL_WAIT);
1160	}
1161
1162	if (count <= 0) {
1163		ath6kl_warn("htc pipe control receive timeout!\n");
1164		return -ETIMEDOUT;
1165	}
1166
1167	return 0;
1168}
1169
1170static void htc_rxctrl_complete(struct htc_target *context,
1171				struct htc_packet *packet)
1172{
1173	struct sk_buff *skb = packet->skb;
1174
1175	if (packet->endpoint == ENDPOINT_0 &&
1176	    packet->status == -ECANCELED &&
1177	    skb != NULL)
1178		dev_kfree_skb(skb);
1179}
1180
1181/* htc pipe initialization */
1182static void reset_endpoint_states(struct htc_target *target)
1183{
1184	struct htc_endpoint *ep;
1185	int i;
1186
1187	for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
1188		ep = &target->endpoint[i];
1189		ep->svc_id = 0;
1190		ep->len_max = 0;
1191		ep->max_txq_depth = 0;
1192		ep->eid = i;
1193		INIT_LIST_HEAD(&ep->txq);
1194		INIT_LIST_HEAD(&ep->pipe.tx_lookup_queue);
1195		INIT_LIST_HEAD(&ep->rx_bufq);
1196		ep->target = target;
1197		ep->pipe.tx_credit_flow_enabled = true;
1198	}
1199}
1200
1201/* start HTC, this is called after all services are connected */
1202static int htc_config_target_hif_pipe(struct htc_target *target)
1203{
1204	return 0;
1205}
1206
1207/* htc service functions */
1208static u8 htc_get_credit_alloc(struct htc_target *target, u16 service_id)
1209{
1210	u8 allocation = 0;
1211	int i;
1212
1213	for (i = 0; i < ENDPOINT_MAX; i++) {
1214		if (target->pipe.txcredit_alloc[i].service_id == service_id)
1215			allocation =
1216				target->pipe.txcredit_alloc[i].credit_alloc;
1217	}
1218
1219	if (allocation == 0) {
1220		ath6kl_dbg(ATH6KL_DBG_HTC,
1221			   "HTC Service TX : 0x%2.2X : allocation is zero!\n",
1222			   service_id);
1223	}
1224
1225	return allocation;
1226}
1227
1228static int ath6kl_htc_pipe_conn_service(struct htc_target *target,
1229		     struct htc_service_connect_req *conn_req,
1230		     struct htc_service_connect_resp *conn_resp)
1231{
1232	struct ath6kl *ar = target->dev->ar;
1233	struct htc_packet *packet = NULL;
1234	struct htc_conn_service_resp *resp_msg;
1235	struct htc_conn_service_msg *conn_msg;
1236	enum htc_endpoint_id assigned_epid = ENDPOINT_MAX;
1237	bool disable_credit_flowctrl = false;
1238	unsigned int max_msg_size = 0;
1239	struct htc_endpoint *ep;
1240	int length, status = 0;
1241	struct sk_buff *skb;
1242	u8 tx_alloc;
1243	u16 flags;
1244
1245	if (conn_req->svc_id == 0) {
1246		WARN_ON_ONCE(1);
1247		status = -EINVAL;
1248		goto free_packet;
1249	}
1250
1251	if (conn_req->svc_id == HTC_CTRL_RSVD_SVC) {
1252		/* special case for pseudo control service */
1253		assigned_epid = ENDPOINT_0;
1254		max_msg_size = HTC_MAX_CTRL_MSG_LEN;
1255		tx_alloc = 0;
1256
1257	} else {
1258		tx_alloc = htc_get_credit_alloc(target, conn_req->svc_id);
1259		if (tx_alloc == 0) {
1260			status = -ENOMEM;
1261			goto free_packet;
1262		}
1263
1264		/* allocate a packet to send to the target */
1265		packet = htc_alloc_txctrl_packet(target);
1266
1267		if (packet == NULL) {
1268			WARN_ON_ONCE(1);
1269			status = -ENOMEM;
1270			goto free_packet;
1271		}
1272
1273		skb = packet->skb;
1274		length = sizeof(struct htc_conn_service_msg);
1275
1276		/* assemble connect service message */
1277		conn_msg = (struct htc_conn_service_msg *) skb_put(skb,
1278								   length);
1279		if (conn_msg == NULL) {
1280			WARN_ON_ONCE(1);
1281			status = -EINVAL;
1282			goto free_packet;
1283		}
1284
1285		memset(conn_msg, 0,
1286		       sizeof(struct htc_conn_service_msg));
1287		conn_msg->msg_id = cpu_to_le16(HTC_MSG_CONN_SVC_ID);
1288		conn_msg->svc_id = cpu_to_le16(conn_req->svc_id);
1289		conn_msg->conn_flags = cpu_to_le16(conn_req->conn_flags &
1290					~HTC_CONN_FLGS_SET_RECV_ALLOC_MASK);
1291
1292		/* tell target desired recv alloc for this ep */
1293		flags = tx_alloc << HTC_CONN_FLGS_SET_RECV_ALLOC_SHIFT;
1294		conn_msg->conn_flags |= cpu_to_le16(flags);
1295
1296		if (conn_req->conn_flags &
1297		    HTC_CONN_FLGS_DISABLE_CRED_FLOW_CTRL) {
1298			disable_credit_flowctrl = true;
1299		}
1300
1301		set_htc_pkt_info(packet, NULL, (u8 *) conn_msg,
1302				 length,
1303				 ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
1304
1305		status = ath6kl_htc_pipe_tx(target, packet);
1306
1307		/* we don't own it anymore */
1308		packet = NULL;
1309		if (status != 0)
1310			goto free_packet;
1311
1312		/* wait for response */
1313		status = htc_wait_recv_ctrl_message(target);
1314		if (status != 0)
1315			goto free_packet;
1316
1317		/* we controlled the buffer creation so it has to be
1318		 * properly aligned
1319		 */
1320		resp_msg = (struct htc_conn_service_resp *)
1321		    target->pipe.ctrl_response_buf;
1322
1323		if (resp_msg->msg_id != cpu_to_le16(HTC_MSG_CONN_SVC_RESP_ID) ||
1324		    (target->pipe.ctrl_response_len < sizeof(*resp_msg))) {
1325			/* this message is not valid */
1326			WARN_ON_ONCE(1);
1327			status = -EINVAL;
1328			goto free_packet;
1329		}
1330
1331		ath6kl_dbg(ATH6KL_DBG_TRC,
1332			   "%s: service 0x%X conn resp: status: %d ep: %d\n",
1333			   __func__, resp_msg->svc_id, resp_msg->status,
1334			   resp_msg->eid);
1335
1336		conn_resp->resp_code = resp_msg->status;
1337		/* check response status */
1338		if (resp_msg->status != HTC_SERVICE_SUCCESS) {
1339			ath6kl_dbg(ATH6KL_DBG_HTC,
1340				   "Target failed service 0x%X connect request (status:%d)\n",
1341				   resp_msg->svc_id, resp_msg->status);
1342			status = -EINVAL;
1343			goto free_packet;
1344		}
1345
1346		assigned_epid = (enum htc_endpoint_id) resp_msg->eid;
1347		max_msg_size = le16_to_cpu(resp_msg->max_msg_sz);
1348	}
1349
1350	/* the rest are parameter checks so set the error status */
1351	status = -EINVAL;
1352
1353	if (assigned_epid >= ENDPOINT_MAX) {
1354		WARN_ON_ONCE(1);
1355		goto free_packet;
1356	}
1357
1358	if (max_msg_size == 0) {
1359		WARN_ON_ONCE(1);
1360		goto free_packet;
1361	}
1362
1363	ep = &target->endpoint[assigned_epid];
1364	ep->eid = assigned_epid;
1365	if (ep->svc_id != 0) {
1366		/* endpoint already in use! */
1367		WARN_ON_ONCE(1);
1368		goto free_packet;
1369	}
1370
1371	/* return assigned endpoint to caller */
1372	conn_resp->endpoint = assigned_epid;
1373	conn_resp->len_max = max_msg_size;
1374
1375	/* setup the endpoint */
1376	ep->svc_id = conn_req->svc_id; /* this marks ep in use */
1377	ep->max_txq_depth = conn_req->max_txq_depth;
1378	ep->len_max = max_msg_size;
1379	ep->cred_dist.credits = tx_alloc;
1380	ep->cred_dist.cred_sz = target->tgt_cred_sz;
1381	ep->cred_dist.cred_per_msg = max_msg_size / target->tgt_cred_sz;
1382	if (max_msg_size % target->tgt_cred_sz)
1383		ep->cred_dist.cred_per_msg++;
1384
1385	/* copy all the callbacks */
1386	ep->ep_cb = conn_req->ep_cb;
1387
1388	/* initialize tx_drop_packet_threshold */
1389	ep->tx_drop_packet_threshold = MAX_HI_COOKIE_NUM;
1390
1391	status = ath6kl_hif_pipe_map_service(ar, ep->svc_id,
1392					     &ep->pipe.pipeid_ul,
1393					     &ep->pipe.pipeid_dl);
1394	if (status != 0)
1395		goto free_packet;
1396
1397	ath6kl_dbg(ATH6KL_DBG_HTC,
1398		   "SVC Ready: 0x%4.4X: ULpipe:%d DLpipe:%d id:%d\n",
1399		   ep->svc_id, ep->pipe.pipeid_ul,
1400		   ep->pipe.pipeid_dl, ep->eid);
1401
1402	if (disable_credit_flowctrl && ep->pipe.tx_credit_flow_enabled) {
1403		ep->pipe.tx_credit_flow_enabled = false;
1404		ath6kl_dbg(ATH6KL_DBG_HTC,
1405			   "SVC: 0x%4.4X ep:%d TX flow control off\n",
1406			   ep->svc_id, assigned_epid);
1407	}
1408
1409free_packet:
1410	if (packet != NULL)
1411		htc_free_txctrl_packet(target, packet);
1412	return status;
1413}
1414
1415/* htc export functions */
1416static void *ath6kl_htc_pipe_create(struct ath6kl *ar)
1417{
1418	int status = 0;
1419	struct htc_endpoint *ep = NULL;
1420	struct htc_target *target = NULL;
1421	struct htc_packet *packet;
1422	int i;
1423
1424	target = kzalloc(sizeof(struct htc_target), GFP_KERNEL);
1425	if (target == NULL) {
1426		ath6kl_err("htc create unable to allocate memory\n");
1427		status = -ENOMEM;
1428		goto fail_htc_create;
1429	}
1430
1431	spin_lock_init(&target->htc_lock);
1432	spin_lock_init(&target->rx_lock);
1433	spin_lock_init(&target->tx_lock);
1434
1435	reset_endpoint_states(target);
1436
1437	for (i = 0; i < HTC_PACKET_CONTAINER_ALLOCATION; i++) {
1438		packet = kzalloc(sizeof(struct htc_packet), GFP_KERNEL);
1439
1440		if (packet != NULL)
1441			free_htc_packet_container(target, packet);
1442	}
1443
1444	target->dev = kzalloc(sizeof(*target->dev), GFP_KERNEL);
1445	if (!target->dev) {
1446		ath6kl_err("unable to allocate memory\n");
1447		status = -ENOMEM;
1448		goto fail_htc_create;
1449	}
1450	target->dev->ar = ar;
1451	target->dev->htc_cnxt = target;
1452
1453	/* Get HIF default pipe for HTC message exchange */
1454	ep = &target->endpoint[ENDPOINT_0];
1455
1456	ath6kl_hif_pipe_get_default(ar, &ep->pipe.pipeid_ul,
1457				    &ep->pipe.pipeid_dl);
1458
1459	return target;
1460
1461fail_htc_create:
1462	if (status != 0) {
1463		if (target != NULL)
1464			ath6kl_htc_pipe_cleanup(target);
1465
1466		target = NULL;
1467	}
1468	return target;
1469}
1470
1471/* cleanup the HTC instance */
1472static void ath6kl_htc_pipe_cleanup(struct htc_target *target)
1473{
1474	struct htc_packet *packet;
1475
1476	while (true) {
1477		packet = alloc_htc_packet_container(target);
1478		if (packet == NULL)
1479			break;
1480		kfree(packet);
1481	}
1482
1483	kfree(target->dev);
1484
1485	/* kfree our instance */
1486	kfree(target);
1487}
1488
1489static int ath6kl_htc_pipe_start(struct htc_target *target)
1490{
1491	struct sk_buff *skb;
1492	struct htc_setup_comp_ext_msg *setup;
1493	struct htc_packet *packet;
1494
1495	htc_config_target_hif_pipe(target);
1496
1497	/* allocate a buffer to send */
1498	packet = htc_alloc_txctrl_packet(target);
1499	if (packet == NULL) {
1500		WARN_ON_ONCE(1);
1501		return -ENOMEM;
1502	}
1503
1504	skb = packet->skb;
1505
1506	/* assemble setup complete message */
1507	setup = (struct htc_setup_comp_ext_msg *) skb_put(skb,
1508							  sizeof(*setup));
1509	memset(setup, 0, sizeof(struct htc_setup_comp_ext_msg));
1510	setup->msg_id = cpu_to_le16(HTC_MSG_SETUP_COMPLETE_EX_ID);
1511
1512	ath6kl_dbg(ATH6KL_DBG_HTC, "HTC using TX credit flow control\n");
1513
1514	set_htc_pkt_info(packet, NULL, (u8 *) setup,
1515			 sizeof(struct htc_setup_comp_ext_msg),
1516			 ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
1517
1518	target->htc_flags |= HTC_OP_STATE_SETUP_COMPLETE;
1519
1520	return ath6kl_htc_pipe_tx(target, packet);
1521}
1522
1523static void ath6kl_htc_pipe_stop(struct htc_target *target)
1524{
1525	int i;
1526	struct htc_endpoint *ep;
1527
1528	/* cleanup endpoints */
1529	for (i = 0; i < ENDPOINT_MAX; i++) {
1530		ep = &target->endpoint[i];
1531		htc_flush_rx_queue(target, ep);
1532		htc_flush_tx_endpoint(target, ep, HTC_TX_PACKET_TAG_ALL);
1533	}
1534
1535	reset_endpoint_states(target);
1536	target->htc_flags &= ~HTC_OP_STATE_SETUP_COMPLETE;
1537}
1538
1539static int ath6kl_htc_pipe_get_rxbuf_num(struct htc_target *target,
1540					 enum htc_endpoint_id endpoint)
1541{
1542	int num;
1543
1544	spin_lock_bh(&target->rx_lock);
1545	num = get_queue_depth(&(target->endpoint[endpoint].rx_bufq));
1546	spin_unlock_bh(&target->rx_lock);
1547
1548	return num;
1549}
1550
1551static int ath6kl_htc_pipe_tx(struct htc_target *target,
1552			      struct htc_packet *packet)
1553{
1554	struct list_head queue;
1555
1556	ath6kl_dbg(ATH6KL_DBG_HTC,
1557		   "%s: endPointId: %d, buffer: 0x%p, length: %d\n",
1558		   __func__, packet->endpoint, packet->buf,
1559		   packet->act_len);
1560
1561	INIT_LIST_HEAD(&queue);
1562	list_add_tail(&packet->list, &queue);
1563
1564	return htc_send_packets_multiple(target, &queue);
1565}
1566
1567static int ath6kl_htc_pipe_wait_target(struct htc_target *target)
1568{
1569	struct htc_ready_ext_msg *ready_msg;
1570	struct htc_service_connect_req connect;
1571	struct htc_service_connect_resp resp;
1572	int status = 0;
1573
1574	status = htc_wait_recv_ctrl_message(target);
1575
1576	if (status != 0)
1577		return status;
1578
1579	if (target->pipe.ctrl_response_len < sizeof(*ready_msg)) {
1580		ath6kl_warn("invalid htc pipe ready msg len: %d\n",
1581			    target->pipe.ctrl_response_len);
1582		return -ECOMM;
1583	}
1584
1585	ready_msg = (struct htc_ready_ext_msg *) target->pipe.ctrl_response_buf;
1586
1587	if (ready_msg->ver2_0_info.msg_id != cpu_to_le16(HTC_MSG_READY_ID)) {
1588		ath6kl_warn("invalid htc pipe ready msg: 0x%x\n",
1589			    ready_msg->ver2_0_info.msg_id);
1590		return -ECOMM;
1591	}
1592
1593	ath6kl_dbg(ATH6KL_DBG_HTC,
1594		   "Target Ready! : transmit resources : %d size:%d\n",
1595		   ready_msg->ver2_0_info.cred_cnt,
1596		   ready_msg->ver2_0_info.cred_sz);
1597
1598	target->tgt_creds = le16_to_cpu(ready_msg->ver2_0_info.cred_cnt);
1599	target->tgt_cred_sz = le16_to_cpu(ready_msg->ver2_0_info.cred_sz);
1600
1601	if ((target->tgt_creds == 0) || (target->tgt_cred_sz == 0))
1602		return -ECOMM;
1603
1604	htc_setup_target_buffer_assignments(target);
1605
1606	/* setup our pseudo HTC control endpoint connection */
1607	memset(&connect, 0, sizeof(connect));
1608	memset(&resp, 0, sizeof(resp));
1609	connect.ep_cb.tx_complete = htc_txctrl_complete;
1610	connect.ep_cb.rx = htc_rxctrl_complete;
1611	connect.max_txq_depth = NUM_CONTROL_TX_BUFFERS;
1612	connect.svc_id = HTC_CTRL_RSVD_SVC;
1613
1614	/* connect fake service */
1615	status = ath6kl_htc_pipe_conn_service(target, &connect, &resp);
1616
1617	return status;
1618}
1619
1620static void ath6kl_htc_pipe_flush_txep(struct htc_target *target,
1621				       enum htc_endpoint_id endpoint, u16 tag)
1622{
1623	struct htc_endpoint *ep = &target->endpoint[endpoint];
1624
1625	if (ep->svc_id == 0) {
1626		WARN_ON_ONCE(1);
1627		/* not in use.. */
1628		return;
1629	}
1630
1631	htc_flush_tx_endpoint(target, ep, tag);
1632}
1633
1634static int ath6kl_htc_pipe_add_rxbuf_multiple(struct htc_target *target,
1635					      struct list_head *pkt_queue)
1636{
1637	struct htc_packet *packet, *tmp_pkt, *first;
1638	struct htc_endpoint *ep;
1639	int status = 0;
1640
1641	if (list_empty(pkt_queue))
1642		return -EINVAL;
1643
1644	first = list_first_entry(pkt_queue, struct htc_packet, list);
1645
1646	if (first->endpoint >= ENDPOINT_MAX) {
1647		WARN_ON_ONCE(1);
1648		return -EINVAL;
1649	}
1650
1651	ath6kl_dbg(ATH6KL_DBG_HTC, "%s: epid: %d, cnt:%d, len: %d\n",
1652		   __func__, first->endpoint, get_queue_depth(pkt_queue),
1653		   first->buf_len);
1654
1655	ep = &target->endpoint[first->endpoint];
1656
1657	spin_lock_bh(&target->rx_lock);
1658
1659	/* store receive packets */
1660	list_splice_tail_init(pkt_queue, &ep->rx_bufq);
1661
1662	spin_unlock_bh(&target->rx_lock);
1663
1664	if (status != 0) {
1665		/* walk through queue and mark each one canceled */
1666		list_for_each_entry_safe(packet, tmp_pkt, pkt_queue, list) {
1667			packet->status = -ECANCELED;
1668		}
1669
1670		do_recv_completion(ep, pkt_queue);
1671	}
1672
1673	return status;
1674}
1675
1676static void ath6kl_htc_pipe_activity_changed(struct htc_target *target,
1677					     enum htc_endpoint_id ep,
1678					     bool active)
1679{
1680	/* TODO */
1681}
1682
1683static void ath6kl_htc_pipe_flush_rx_buf(struct htc_target *target)
1684{
1685	struct htc_endpoint *endpoint;
1686	struct htc_packet *packet, *tmp_pkt;
1687	int i;
1688
1689	for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
1690		endpoint = &target->endpoint[i];
1691
1692		spin_lock_bh(&target->rx_lock);
1693
1694		list_for_each_entry_safe(packet, tmp_pkt,
1695					 &endpoint->rx_bufq, list) {
1696			list_del(&packet->list);
1697			spin_unlock_bh(&target->rx_lock);
1698			ath6kl_dbg(ATH6KL_DBG_HTC,
1699				   "htc rx flush pkt 0x%p len %d ep %d\n",
1700				   packet, packet->buf_len,
1701				   packet->endpoint);
1702			dev_kfree_skb(packet->pkt_cntxt);
1703			spin_lock_bh(&target->rx_lock);
1704		}
1705
1706		spin_unlock_bh(&target->rx_lock);
1707	}
1708}
1709
1710static int ath6kl_htc_pipe_credit_setup(struct htc_target *target,
1711					struct ath6kl_htc_credit_info *info)
1712{
1713	return 0;
1714}
1715
1716static const struct ath6kl_htc_ops ath6kl_htc_pipe_ops = {
1717	.create = ath6kl_htc_pipe_create,
1718	.wait_target = ath6kl_htc_pipe_wait_target,
1719	.start = ath6kl_htc_pipe_start,
1720	.conn_service = ath6kl_htc_pipe_conn_service,
1721	.tx = ath6kl_htc_pipe_tx,
1722	.stop = ath6kl_htc_pipe_stop,
1723	.cleanup = ath6kl_htc_pipe_cleanup,
1724	.flush_txep = ath6kl_htc_pipe_flush_txep,
1725	.flush_rx_buf = ath6kl_htc_pipe_flush_rx_buf,
1726	.activity_changed = ath6kl_htc_pipe_activity_changed,
1727	.get_rxbuf_num = ath6kl_htc_pipe_get_rxbuf_num,
1728	.add_rxbuf_multiple = ath6kl_htc_pipe_add_rxbuf_multiple,
1729	.credit_setup = ath6kl_htc_pipe_credit_setup,
1730	.tx_complete = ath6kl_htc_pipe_tx_complete,
1731	.rx_complete = ath6kl_htc_pipe_rx_complete,
1732};
1733
1734void ath6kl_htc_pipe_attach(struct ath6kl *ar)
1735{
1736	ar->htc_ops = &ath6kl_htc_pipe_ops;
1737}
1738