xref: /openbmc/linux/drivers/bluetooth/hci_qca.c (revision 5d0e4d78)
1 /*
2  *  Bluetooth Software UART Qualcomm protocol
3  *
4  *  HCI_IBS (HCI In-Band Sleep) is Qualcomm's power management
5  *  protocol extension to H4.
6  *
7  *  Copyright (C) 2007 Texas Instruments, Inc.
8  *  Copyright (c) 2010, 2012 The Linux Foundation. All rights reserved.
9  *
10  *  Acknowledgements:
11  *  This file is based on hci_ll.c, which was...
12  *  Written by Ohad Ben-Cohen <ohad@bencohen.org>
13  *  which was in turn based on hci_h4.c, which was written
14  *  by Maxim Krasnyansky and Marcel Holtmann.
15  *
16  *  This program is free software; you can redistribute it and/or modify
17  *  it under the terms of the GNU General Public License version 2
18  *  as published by the Free Software Foundation
19  *
20  *  This program is distributed in the hope that it will be useful,
21  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
22  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
23  *  GNU General Public License for more details.
24  *
25  *  You should have received a copy of the GNU General Public License
26  *  along with this program; if not, write to the Free Software
27  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
28  *
29  */
30 
31 #include <linux/kernel.h>
32 #include <linux/debugfs.h>
33 
34 #include <net/bluetooth/bluetooth.h>
35 #include <net/bluetooth/hci_core.h>
36 
37 #include "hci_uart.h"
38 #include "btqca.h"
39 
40 /* HCI_IBS protocol messages */
41 #define HCI_IBS_SLEEP_IND	0xFE
42 #define HCI_IBS_WAKE_IND	0xFD
43 #define HCI_IBS_WAKE_ACK	0xFC
44 #define HCI_MAX_IBS_SIZE	10
45 
46 /* Controller states */
47 #define STATE_IN_BAND_SLEEP_ENABLED	1
48 
49 #define IBS_WAKE_RETRANS_TIMEOUT_MS	100
50 #define IBS_TX_IDLE_TIMEOUT_MS		2000
51 #define BAUDRATE_SETTLE_TIMEOUT_MS	300
52 
53 /* HCI_IBS transmit side sleep protocol states */
54 enum tx_ibs_states {
55 	HCI_IBS_TX_ASLEEP,
56 	HCI_IBS_TX_WAKING,
57 	HCI_IBS_TX_AWAKE,
58 };
59 
60 /* HCI_IBS receive side sleep protocol states */
61 enum rx_states {
62 	HCI_IBS_RX_ASLEEP,
63 	HCI_IBS_RX_AWAKE,
64 };
65 
66 /* HCI_IBS transmit and receive side clock state vote */
67 enum hci_ibs_clock_state_vote {
68 	HCI_IBS_VOTE_STATS_UPDATE,
69 	HCI_IBS_TX_VOTE_CLOCK_ON,
70 	HCI_IBS_TX_VOTE_CLOCK_OFF,
71 	HCI_IBS_RX_VOTE_CLOCK_ON,
72 	HCI_IBS_RX_VOTE_CLOCK_OFF,
73 };
74 
75 struct qca_data {
76 	struct hci_uart *hu;
77 	struct sk_buff *rx_skb;
78 	struct sk_buff_head txq;
79 	struct sk_buff_head tx_wait_q;	/* HCI_IBS wait queue	*/
80 	spinlock_t hci_ibs_lock;	/* HCI_IBS state lock	*/
81 	u8 tx_ibs_state;	/* HCI_IBS transmit side power state*/
82 	u8 rx_ibs_state;	/* HCI_IBS receive side power state */
83 	bool tx_vote;		/* Clock must be on for TX */
84 	bool rx_vote;		/* Clock must be on for RX */
85 	struct timer_list tx_idle_timer;
86 	u32 tx_idle_delay;
87 	struct timer_list wake_retrans_timer;
88 	u32 wake_retrans;
89 	struct workqueue_struct *workqueue;
90 	struct work_struct ws_awake_rx;
91 	struct work_struct ws_awake_device;
92 	struct work_struct ws_rx_vote_off;
93 	struct work_struct ws_tx_vote_off;
94 	unsigned long flags;
95 
96 	/* For debugging purpose */
97 	u64 ibs_sent_wacks;
98 	u64 ibs_sent_slps;
99 	u64 ibs_sent_wakes;
100 	u64 ibs_recv_wacks;
101 	u64 ibs_recv_slps;
102 	u64 ibs_recv_wakes;
103 	u64 vote_last_jif;
104 	u32 vote_on_ms;
105 	u32 vote_off_ms;
106 	u64 tx_votes_on;
107 	u64 rx_votes_on;
108 	u64 tx_votes_off;
109 	u64 rx_votes_off;
110 	u64 votes_on;
111 	u64 votes_off;
112 };
113 
114 static void __serial_clock_on(struct tty_struct *tty)
115 {
116 	/* TODO: Some chipset requires to enable UART clock on client
117 	 * side to save power consumption or manual work is required.
118 	 * Please put your code to control UART clock here if needed
119 	 */
120 }
121 
122 static void __serial_clock_off(struct tty_struct *tty)
123 {
124 	/* TODO: Some chipset requires to disable UART clock on client
125 	 * side to save power consumption or manual work is required.
126 	 * Please put your code to control UART clock off here if needed
127 	 */
128 }
129 
130 /* serial_clock_vote needs to be called with the ibs lock held */
131 static void serial_clock_vote(unsigned long vote, struct hci_uart *hu)
132 {
133 	struct qca_data *qca = hu->priv;
134 	unsigned int diff;
135 
136 	bool old_vote = (qca->tx_vote | qca->rx_vote);
137 	bool new_vote;
138 
139 	switch (vote) {
140 	case HCI_IBS_VOTE_STATS_UPDATE:
141 		diff = jiffies_to_msecs(jiffies - qca->vote_last_jif);
142 
143 		if (old_vote)
144 			qca->vote_off_ms += diff;
145 		else
146 			qca->vote_on_ms += diff;
147 		return;
148 
149 	case HCI_IBS_TX_VOTE_CLOCK_ON:
150 		qca->tx_vote = true;
151 		qca->tx_votes_on++;
152 		new_vote = true;
153 		break;
154 
155 	case HCI_IBS_RX_VOTE_CLOCK_ON:
156 		qca->rx_vote = true;
157 		qca->rx_votes_on++;
158 		new_vote = true;
159 		break;
160 
161 	case HCI_IBS_TX_VOTE_CLOCK_OFF:
162 		qca->tx_vote = false;
163 		qca->tx_votes_off++;
164 		new_vote = qca->rx_vote | qca->tx_vote;
165 		break;
166 
167 	case HCI_IBS_RX_VOTE_CLOCK_OFF:
168 		qca->rx_vote = false;
169 		qca->rx_votes_off++;
170 		new_vote = qca->rx_vote | qca->tx_vote;
171 		break;
172 
173 	default:
174 		BT_ERR("Voting irregularity");
175 		return;
176 	}
177 
178 	if (new_vote != old_vote) {
179 		if (new_vote)
180 			__serial_clock_on(hu->tty);
181 		else
182 			__serial_clock_off(hu->tty);
183 
184 		BT_DBG("Vote serial clock %s(%s)", new_vote ? "true" : "false",
185 		       vote ? "true" : "false");
186 
187 		diff = jiffies_to_msecs(jiffies - qca->vote_last_jif);
188 
189 		if (new_vote) {
190 			qca->votes_on++;
191 			qca->vote_off_ms += diff;
192 		} else {
193 			qca->votes_off++;
194 			qca->vote_on_ms += diff;
195 		}
196 		qca->vote_last_jif = jiffies;
197 	}
198 }
199 
200 /* Builds and sends an HCI_IBS command packet.
201  * These are very simple packets with only 1 cmd byte.
202  */
203 static int send_hci_ibs_cmd(u8 cmd, struct hci_uart *hu)
204 {
205 	int err = 0;
206 	struct sk_buff *skb = NULL;
207 	struct qca_data *qca = hu->priv;
208 
209 	BT_DBG("hu %p send hci ibs cmd 0x%x", hu, cmd);
210 
211 	skb = bt_skb_alloc(1, GFP_ATOMIC);
212 	if (!skb) {
213 		BT_ERR("Failed to allocate memory for HCI_IBS packet");
214 		return -ENOMEM;
215 	}
216 
217 	/* Assign HCI_IBS type */
218 	skb_put_u8(skb, cmd);
219 
220 	skb_queue_tail(&qca->txq, skb);
221 
222 	return err;
223 }
224 
225 static void qca_wq_awake_device(struct work_struct *work)
226 {
227 	struct qca_data *qca = container_of(work, struct qca_data,
228 					    ws_awake_device);
229 	struct hci_uart *hu = qca->hu;
230 	unsigned long retrans_delay;
231 
232 	BT_DBG("hu %p wq awake device", hu);
233 
234 	/* Vote for serial clock */
235 	serial_clock_vote(HCI_IBS_TX_VOTE_CLOCK_ON, hu);
236 
237 	spin_lock(&qca->hci_ibs_lock);
238 
239 	/* Send wake indication to device */
240 	if (send_hci_ibs_cmd(HCI_IBS_WAKE_IND, hu) < 0)
241 		BT_ERR("Failed to send WAKE to device");
242 
243 	qca->ibs_sent_wakes++;
244 
245 	/* Start retransmit timer */
246 	retrans_delay = msecs_to_jiffies(qca->wake_retrans);
247 	mod_timer(&qca->wake_retrans_timer, jiffies + retrans_delay);
248 
249 	spin_unlock(&qca->hci_ibs_lock);
250 
251 	/* Actually send the packets */
252 	hci_uart_tx_wakeup(hu);
253 }
254 
255 static void qca_wq_awake_rx(struct work_struct *work)
256 {
257 	struct qca_data *qca = container_of(work, struct qca_data,
258 					    ws_awake_rx);
259 	struct hci_uart *hu = qca->hu;
260 
261 	BT_DBG("hu %p wq awake rx", hu);
262 
263 	serial_clock_vote(HCI_IBS_RX_VOTE_CLOCK_ON, hu);
264 
265 	spin_lock(&qca->hci_ibs_lock);
266 	qca->rx_ibs_state = HCI_IBS_RX_AWAKE;
267 
268 	/* Always acknowledge device wake up,
269 	 * sending IBS message doesn't count as TX ON.
270 	 */
271 	if (send_hci_ibs_cmd(HCI_IBS_WAKE_ACK, hu) < 0)
272 		BT_ERR("Failed to acknowledge device wake up");
273 
274 	qca->ibs_sent_wacks++;
275 
276 	spin_unlock(&qca->hci_ibs_lock);
277 
278 	/* Actually send the packets */
279 	hci_uart_tx_wakeup(hu);
280 }
281 
282 static void qca_wq_serial_rx_clock_vote_off(struct work_struct *work)
283 {
284 	struct qca_data *qca = container_of(work, struct qca_data,
285 					    ws_rx_vote_off);
286 	struct hci_uart *hu = qca->hu;
287 
288 	BT_DBG("hu %p rx clock vote off", hu);
289 
290 	serial_clock_vote(HCI_IBS_RX_VOTE_CLOCK_OFF, hu);
291 }
292 
293 static void qca_wq_serial_tx_clock_vote_off(struct work_struct *work)
294 {
295 	struct qca_data *qca = container_of(work, struct qca_data,
296 					    ws_tx_vote_off);
297 	struct hci_uart *hu = qca->hu;
298 
299 	BT_DBG("hu %p tx clock vote off", hu);
300 
301 	/* Run HCI tx handling unlocked */
302 	hci_uart_tx_wakeup(hu);
303 
304 	/* Now that message queued to tty driver, vote for tty clocks off.
305 	 * It is up to the tty driver to pend the clocks off until tx done.
306 	 */
307 	serial_clock_vote(HCI_IBS_TX_VOTE_CLOCK_OFF, hu);
308 }
309 
310 static void hci_ibs_tx_idle_timeout(unsigned long arg)
311 {
312 	struct hci_uart *hu = (struct hci_uart *)arg;
313 	struct qca_data *qca = hu->priv;
314 	unsigned long flags;
315 
316 	BT_DBG("hu %p idle timeout in %d state", hu, qca->tx_ibs_state);
317 
318 	spin_lock_irqsave_nested(&qca->hci_ibs_lock,
319 				 flags, SINGLE_DEPTH_NESTING);
320 
321 	switch (qca->tx_ibs_state) {
322 	case HCI_IBS_TX_AWAKE:
323 		/* TX_IDLE, go to SLEEP */
324 		if (send_hci_ibs_cmd(HCI_IBS_SLEEP_IND, hu) < 0) {
325 			BT_ERR("Failed to send SLEEP to device");
326 			break;
327 		}
328 		qca->tx_ibs_state = HCI_IBS_TX_ASLEEP;
329 		qca->ibs_sent_slps++;
330 		queue_work(qca->workqueue, &qca->ws_tx_vote_off);
331 		break;
332 
333 	case HCI_IBS_TX_ASLEEP:
334 	case HCI_IBS_TX_WAKING:
335 		/* Fall through */
336 
337 	default:
338 		BT_ERR("Spurious timeout tx state %d", qca->tx_ibs_state);
339 		break;
340 	}
341 
342 	spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
343 }
344 
345 static void hci_ibs_wake_retrans_timeout(unsigned long arg)
346 {
347 	struct hci_uart *hu = (struct hci_uart *)arg;
348 	struct qca_data *qca = hu->priv;
349 	unsigned long flags, retrans_delay;
350 	bool retransmit = false;
351 
352 	BT_DBG("hu %p wake retransmit timeout in %d state",
353 		hu, qca->tx_ibs_state);
354 
355 	spin_lock_irqsave_nested(&qca->hci_ibs_lock,
356 				 flags, SINGLE_DEPTH_NESTING);
357 
358 	switch (qca->tx_ibs_state) {
359 	case HCI_IBS_TX_WAKING:
360 		/* No WAKE_ACK, retransmit WAKE */
361 		retransmit = true;
362 		if (send_hci_ibs_cmd(HCI_IBS_WAKE_IND, hu) < 0) {
363 			BT_ERR("Failed to acknowledge device wake up");
364 			break;
365 		}
366 		qca->ibs_sent_wakes++;
367 		retrans_delay = msecs_to_jiffies(qca->wake_retrans);
368 		mod_timer(&qca->wake_retrans_timer, jiffies + retrans_delay);
369 		break;
370 
371 	case HCI_IBS_TX_ASLEEP:
372 	case HCI_IBS_TX_AWAKE:
373 		/* Fall through */
374 
375 	default:
376 		BT_ERR("Spurious timeout tx state %d", qca->tx_ibs_state);
377 		break;
378 	}
379 
380 	spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
381 
382 	if (retransmit)
383 		hci_uart_tx_wakeup(hu);
384 }
385 
386 /* Initialize protocol */
387 static int qca_open(struct hci_uart *hu)
388 {
389 	struct qca_data *qca;
390 
391 	BT_DBG("hu %p qca_open", hu);
392 
393 	qca = kzalloc(sizeof(struct qca_data), GFP_ATOMIC);
394 	if (!qca)
395 		return -ENOMEM;
396 
397 	skb_queue_head_init(&qca->txq);
398 	skb_queue_head_init(&qca->tx_wait_q);
399 	spin_lock_init(&qca->hci_ibs_lock);
400 	qca->workqueue = alloc_ordered_workqueue("qca_wq", 0);
401 	if (!qca->workqueue) {
402 		BT_ERR("QCA Workqueue not initialized properly");
403 		kfree(qca);
404 		return -ENOMEM;
405 	}
406 
407 	INIT_WORK(&qca->ws_awake_rx, qca_wq_awake_rx);
408 	INIT_WORK(&qca->ws_awake_device, qca_wq_awake_device);
409 	INIT_WORK(&qca->ws_rx_vote_off, qca_wq_serial_rx_clock_vote_off);
410 	INIT_WORK(&qca->ws_tx_vote_off, qca_wq_serial_tx_clock_vote_off);
411 
412 	qca->hu = hu;
413 
414 	/* Assume we start with both sides asleep -- extra wakes OK */
415 	qca->tx_ibs_state = HCI_IBS_TX_ASLEEP;
416 	qca->rx_ibs_state = HCI_IBS_RX_ASLEEP;
417 
418 	/* clocks actually on, but we start votes off */
419 	qca->tx_vote = false;
420 	qca->rx_vote = false;
421 	qca->flags = 0;
422 
423 	qca->ibs_sent_wacks = 0;
424 	qca->ibs_sent_slps = 0;
425 	qca->ibs_sent_wakes = 0;
426 	qca->ibs_recv_wacks = 0;
427 	qca->ibs_recv_slps = 0;
428 	qca->ibs_recv_wakes = 0;
429 	qca->vote_last_jif = jiffies;
430 	qca->vote_on_ms = 0;
431 	qca->vote_off_ms = 0;
432 	qca->votes_on = 0;
433 	qca->votes_off = 0;
434 	qca->tx_votes_on = 0;
435 	qca->tx_votes_off = 0;
436 	qca->rx_votes_on = 0;
437 	qca->rx_votes_off = 0;
438 
439 	hu->priv = qca;
440 
441 	setup_timer(&qca->wake_retrans_timer, hci_ibs_wake_retrans_timeout,
442 		    (u_long)hu);
443 	qca->wake_retrans = IBS_WAKE_RETRANS_TIMEOUT_MS;
444 
445 	setup_timer(&qca->tx_idle_timer, hci_ibs_tx_idle_timeout, (u_long)hu);
446 	qca->tx_idle_delay = IBS_TX_IDLE_TIMEOUT_MS;
447 
448 	BT_DBG("HCI_UART_QCA open, tx_idle_delay=%u, wake_retrans=%u",
449 	       qca->tx_idle_delay, qca->wake_retrans);
450 
451 	return 0;
452 }
453 
454 static void qca_debugfs_init(struct hci_dev *hdev)
455 {
456 	struct hci_uart *hu = hci_get_drvdata(hdev);
457 	struct qca_data *qca = hu->priv;
458 	struct dentry *ibs_dir;
459 	umode_t mode;
460 
461 	if (!hdev->debugfs)
462 		return;
463 
464 	ibs_dir = debugfs_create_dir("ibs", hdev->debugfs);
465 
466 	/* read only */
467 	mode = S_IRUGO;
468 	debugfs_create_u8("tx_ibs_state", mode, ibs_dir, &qca->tx_ibs_state);
469 	debugfs_create_u8("rx_ibs_state", mode, ibs_dir, &qca->rx_ibs_state);
470 	debugfs_create_u64("ibs_sent_sleeps", mode, ibs_dir,
471 			   &qca->ibs_sent_slps);
472 	debugfs_create_u64("ibs_sent_wakes", mode, ibs_dir,
473 			   &qca->ibs_sent_wakes);
474 	debugfs_create_u64("ibs_sent_wake_acks", mode, ibs_dir,
475 			   &qca->ibs_sent_wacks);
476 	debugfs_create_u64("ibs_recv_sleeps", mode, ibs_dir,
477 			   &qca->ibs_recv_slps);
478 	debugfs_create_u64("ibs_recv_wakes", mode, ibs_dir,
479 			   &qca->ibs_recv_wakes);
480 	debugfs_create_u64("ibs_recv_wake_acks", mode, ibs_dir,
481 			   &qca->ibs_recv_wacks);
482 	debugfs_create_bool("tx_vote", mode, ibs_dir, &qca->tx_vote);
483 	debugfs_create_u64("tx_votes_on", mode, ibs_dir, &qca->tx_votes_on);
484 	debugfs_create_u64("tx_votes_off", mode, ibs_dir, &qca->tx_votes_off);
485 	debugfs_create_bool("rx_vote", mode, ibs_dir, &qca->rx_vote);
486 	debugfs_create_u64("rx_votes_on", mode, ibs_dir, &qca->rx_votes_on);
487 	debugfs_create_u64("rx_votes_off", mode, ibs_dir, &qca->rx_votes_off);
488 	debugfs_create_u64("votes_on", mode, ibs_dir, &qca->votes_on);
489 	debugfs_create_u64("votes_off", mode, ibs_dir, &qca->votes_off);
490 	debugfs_create_u32("vote_on_ms", mode, ibs_dir, &qca->vote_on_ms);
491 	debugfs_create_u32("vote_off_ms", mode, ibs_dir, &qca->vote_off_ms);
492 
493 	/* read/write */
494 	mode = S_IRUGO | S_IWUSR;
495 	debugfs_create_u32("wake_retrans", mode, ibs_dir, &qca->wake_retrans);
496 	debugfs_create_u32("tx_idle_delay", mode, ibs_dir,
497 			   &qca->tx_idle_delay);
498 }
499 
500 /* Flush protocol data */
501 static int qca_flush(struct hci_uart *hu)
502 {
503 	struct qca_data *qca = hu->priv;
504 
505 	BT_DBG("hu %p qca flush", hu);
506 
507 	skb_queue_purge(&qca->tx_wait_q);
508 	skb_queue_purge(&qca->txq);
509 
510 	return 0;
511 }
512 
513 /* Close protocol */
514 static int qca_close(struct hci_uart *hu)
515 {
516 	struct qca_data *qca = hu->priv;
517 
518 	BT_DBG("hu %p qca close", hu);
519 
520 	serial_clock_vote(HCI_IBS_VOTE_STATS_UPDATE, hu);
521 
522 	skb_queue_purge(&qca->tx_wait_q);
523 	skb_queue_purge(&qca->txq);
524 	del_timer(&qca->tx_idle_timer);
525 	del_timer(&qca->wake_retrans_timer);
526 	destroy_workqueue(qca->workqueue);
527 	qca->hu = NULL;
528 
529 	kfree_skb(qca->rx_skb);
530 
531 	hu->priv = NULL;
532 
533 	kfree(qca);
534 
535 	return 0;
536 }
537 
538 /* Called upon a wake-up-indication from the device.
539  */
540 static void device_want_to_wakeup(struct hci_uart *hu)
541 {
542 	unsigned long flags;
543 	struct qca_data *qca = hu->priv;
544 
545 	BT_DBG("hu %p want to wake up", hu);
546 
547 	spin_lock_irqsave(&qca->hci_ibs_lock, flags);
548 
549 	qca->ibs_recv_wakes++;
550 
551 	switch (qca->rx_ibs_state) {
552 	case HCI_IBS_RX_ASLEEP:
553 		/* Make sure clock is on - we may have turned clock off since
554 		 * receiving the wake up indicator awake rx clock.
555 		 */
556 		queue_work(qca->workqueue, &qca->ws_awake_rx);
557 		spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
558 		return;
559 
560 	case HCI_IBS_RX_AWAKE:
561 		/* Always acknowledge device wake up,
562 		 * sending IBS message doesn't count as TX ON.
563 		 */
564 		if (send_hci_ibs_cmd(HCI_IBS_WAKE_ACK, hu) < 0) {
565 			BT_ERR("Failed to acknowledge device wake up");
566 			break;
567 		}
568 		qca->ibs_sent_wacks++;
569 		break;
570 
571 	default:
572 		/* Any other state is illegal */
573 		BT_ERR("Received HCI_IBS_WAKE_IND in rx state %d",
574 		       qca->rx_ibs_state);
575 		break;
576 	}
577 
578 	spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
579 
580 	/* Actually send the packets */
581 	hci_uart_tx_wakeup(hu);
582 }
583 
584 /* Called upon a sleep-indication from the device.
585  */
586 static void device_want_to_sleep(struct hci_uart *hu)
587 {
588 	unsigned long flags;
589 	struct qca_data *qca = hu->priv;
590 
591 	BT_DBG("hu %p want to sleep", hu);
592 
593 	spin_lock_irqsave(&qca->hci_ibs_lock, flags);
594 
595 	qca->ibs_recv_slps++;
596 
597 	switch (qca->rx_ibs_state) {
598 	case HCI_IBS_RX_AWAKE:
599 		/* Update state */
600 		qca->rx_ibs_state = HCI_IBS_RX_ASLEEP;
601 		/* Vote off rx clock under workqueue */
602 		queue_work(qca->workqueue, &qca->ws_rx_vote_off);
603 		break;
604 
605 	case HCI_IBS_RX_ASLEEP:
606 		/* Fall through */
607 
608 	default:
609 		/* Any other state is illegal */
610 		BT_ERR("Received HCI_IBS_SLEEP_IND in rx state %d",
611 		       qca->rx_ibs_state);
612 		break;
613 	}
614 
615 	spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
616 }
617 
618 /* Called upon wake-up-acknowledgement from the device
619  */
620 static void device_woke_up(struct hci_uart *hu)
621 {
622 	unsigned long flags, idle_delay;
623 	struct qca_data *qca = hu->priv;
624 	struct sk_buff *skb = NULL;
625 
626 	BT_DBG("hu %p woke up", hu);
627 
628 	spin_lock_irqsave(&qca->hci_ibs_lock, flags);
629 
630 	qca->ibs_recv_wacks++;
631 
632 	switch (qca->tx_ibs_state) {
633 	case HCI_IBS_TX_AWAKE:
634 		/* Expect one if we send 2 WAKEs */
635 		BT_DBG("Received HCI_IBS_WAKE_ACK in tx state %d",
636 		       qca->tx_ibs_state);
637 		break;
638 
639 	case HCI_IBS_TX_WAKING:
640 		/* Send pending packets */
641 		while ((skb = skb_dequeue(&qca->tx_wait_q)))
642 			skb_queue_tail(&qca->txq, skb);
643 
644 		/* Switch timers and change state to HCI_IBS_TX_AWAKE */
645 		del_timer(&qca->wake_retrans_timer);
646 		idle_delay = msecs_to_jiffies(qca->tx_idle_delay);
647 		mod_timer(&qca->tx_idle_timer, jiffies + idle_delay);
648 		qca->tx_ibs_state = HCI_IBS_TX_AWAKE;
649 		break;
650 
651 	case HCI_IBS_TX_ASLEEP:
652 		/* Fall through */
653 
654 	default:
655 		BT_ERR("Received HCI_IBS_WAKE_ACK in tx state %d",
656 		       qca->tx_ibs_state);
657 		break;
658 	}
659 
660 	spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
661 
662 	/* Actually send the packets */
663 	hci_uart_tx_wakeup(hu);
664 }
665 
666 /* Enqueue frame for transmittion (padding, crc, etc) may be called from
667  * two simultaneous tasklets.
668  */
669 static int qca_enqueue(struct hci_uart *hu, struct sk_buff *skb)
670 {
671 	unsigned long flags = 0, idle_delay;
672 	struct qca_data *qca = hu->priv;
673 
674 	BT_DBG("hu %p qca enq skb %p tx_ibs_state %d", hu, skb,
675 	       qca->tx_ibs_state);
676 
677 	/* Prepend skb with frame type */
678 	memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
679 
680 	/* Don't go to sleep in middle of patch download or
681 	 * Out-Of-Band(GPIOs control) sleep is selected.
682 	 */
683 	if (!test_bit(STATE_IN_BAND_SLEEP_ENABLED, &qca->flags)) {
684 		skb_queue_tail(&qca->txq, skb);
685 		return 0;
686 	}
687 
688 	spin_lock_irqsave(&qca->hci_ibs_lock, flags);
689 
690 	/* Act according to current state */
691 	switch (qca->tx_ibs_state) {
692 	case HCI_IBS_TX_AWAKE:
693 		BT_DBG("Device awake, sending normally");
694 		skb_queue_tail(&qca->txq, skb);
695 		idle_delay = msecs_to_jiffies(qca->tx_idle_delay);
696 		mod_timer(&qca->tx_idle_timer, jiffies + idle_delay);
697 		break;
698 
699 	case HCI_IBS_TX_ASLEEP:
700 		BT_DBG("Device asleep, waking up and queueing packet");
701 		/* Save packet for later */
702 		skb_queue_tail(&qca->tx_wait_q, skb);
703 
704 		qca->tx_ibs_state = HCI_IBS_TX_WAKING;
705 		/* Schedule a work queue to wake up device */
706 		queue_work(qca->workqueue, &qca->ws_awake_device);
707 		break;
708 
709 	case HCI_IBS_TX_WAKING:
710 		BT_DBG("Device waking up, queueing packet");
711 		/* Transient state; just keep packet for later */
712 		skb_queue_tail(&qca->tx_wait_q, skb);
713 		break;
714 
715 	default:
716 		BT_ERR("Illegal tx state: %d (losing packet)",
717 		       qca->tx_ibs_state);
718 		kfree_skb(skb);
719 		break;
720 	}
721 
722 	spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
723 
724 	return 0;
725 }
726 
727 static int qca_ibs_sleep_ind(struct hci_dev *hdev, struct sk_buff *skb)
728 {
729 	struct hci_uart *hu = hci_get_drvdata(hdev);
730 
731 	BT_DBG("hu %p recv hci ibs cmd 0x%x", hu, HCI_IBS_SLEEP_IND);
732 
733 	device_want_to_sleep(hu);
734 
735 	kfree_skb(skb);
736 	return 0;
737 }
738 
739 static int qca_ibs_wake_ind(struct hci_dev *hdev, struct sk_buff *skb)
740 {
741 	struct hci_uart *hu = hci_get_drvdata(hdev);
742 
743 	BT_DBG("hu %p recv hci ibs cmd 0x%x", hu, HCI_IBS_WAKE_IND);
744 
745 	device_want_to_wakeup(hu);
746 
747 	kfree_skb(skb);
748 	return 0;
749 }
750 
751 static int qca_ibs_wake_ack(struct hci_dev *hdev, struct sk_buff *skb)
752 {
753 	struct hci_uart *hu = hci_get_drvdata(hdev);
754 
755 	BT_DBG("hu %p recv hci ibs cmd 0x%x", hu, HCI_IBS_WAKE_ACK);
756 
757 	device_woke_up(hu);
758 
759 	kfree_skb(skb);
760 	return 0;
761 }
762 
763 #define QCA_IBS_SLEEP_IND_EVENT \
764 	.type = HCI_IBS_SLEEP_IND, \
765 	.hlen = 0, \
766 	.loff = 0, \
767 	.lsize = 0, \
768 	.maxlen = HCI_MAX_IBS_SIZE
769 
770 #define QCA_IBS_WAKE_IND_EVENT \
771 	.type = HCI_IBS_WAKE_IND, \
772 	.hlen = 0, \
773 	.loff = 0, \
774 	.lsize = 0, \
775 	.maxlen = HCI_MAX_IBS_SIZE
776 
777 #define QCA_IBS_WAKE_ACK_EVENT \
778 	.type = HCI_IBS_WAKE_ACK, \
779 	.hlen = 0, \
780 	.loff = 0, \
781 	.lsize = 0, \
782 	.maxlen = HCI_MAX_IBS_SIZE
783 
784 static const struct h4_recv_pkt qca_recv_pkts[] = {
785 	{ H4_RECV_ACL,             .recv = hci_recv_frame    },
786 	{ H4_RECV_SCO,             .recv = hci_recv_frame    },
787 	{ H4_RECV_EVENT,           .recv = hci_recv_frame    },
788 	{ QCA_IBS_WAKE_IND_EVENT,  .recv = qca_ibs_wake_ind  },
789 	{ QCA_IBS_WAKE_ACK_EVENT,  .recv = qca_ibs_wake_ack  },
790 	{ QCA_IBS_SLEEP_IND_EVENT, .recv = qca_ibs_sleep_ind },
791 };
792 
793 static int qca_recv(struct hci_uart *hu, const void *data, int count)
794 {
795 	struct qca_data *qca = hu->priv;
796 
797 	if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
798 		return -EUNATCH;
799 
800 	qca->rx_skb = h4_recv_buf(hu->hdev, qca->rx_skb, data, count,
801 				  qca_recv_pkts, ARRAY_SIZE(qca_recv_pkts));
802 	if (IS_ERR(qca->rx_skb)) {
803 		int err = PTR_ERR(qca->rx_skb);
804 		BT_ERR("%s: Frame reassembly failed (%d)", hu->hdev->name, err);
805 		qca->rx_skb = NULL;
806 		return err;
807 	}
808 
809 	return count;
810 }
811 
812 static struct sk_buff *qca_dequeue(struct hci_uart *hu)
813 {
814 	struct qca_data *qca = hu->priv;
815 
816 	return skb_dequeue(&qca->txq);
817 }
818 
819 static uint8_t qca_get_baudrate_value(int speed)
820 {
821 	switch (speed) {
822 	case 9600:
823 		return QCA_BAUDRATE_9600;
824 	case 19200:
825 		return QCA_BAUDRATE_19200;
826 	case 38400:
827 		return QCA_BAUDRATE_38400;
828 	case 57600:
829 		return QCA_BAUDRATE_57600;
830 	case 115200:
831 		return QCA_BAUDRATE_115200;
832 	case 230400:
833 		return QCA_BAUDRATE_230400;
834 	case 460800:
835 		return QCA_BAUDRATE_460800;
836 	case 500000:
837 		return QCA_BAUDRATE_500000;
838 	case 921600:
839 		return QCA_BAUDRATE_921600;
840 	case 1000000:
841 		return QCA_BAUDRATE_1000000;
842 	case 2000000:
843 		return QCA_BAUDRATE_2000000;
844 	case 3000000:
845 		return QCA_BAUDRATE_3000000;
846 	case 3500000:
847 		return QCA_BAUDRATE_3500000;
848 	default:
849 		return QCA_BAUDRATE_115200;
850 	}
851 }
852 
853 static int qca_set_baudrate(struct hci_dev *hdev, uint8_t baudrate)
854 {
855 	struct hci_uart *hu = hci_get_drvdata(hdev);
856 	struct qca_data *qca = hu->priv;
857 	struct sk_buff *skb;
858 	u8 cmd[] = { 0x01, 0x48, 0xFC, 0x01, 0x00 };
859 
860 	if (baudrate > QCA_BAUDRATE_3000000)
861 		return -EINVAL;
862 
863 	cmd[4] = baudrate;
864 
865 	skb = bt_skb_alloc(sizeof(cmd), GFP_ATOMIC);
866 	if (!skb) {
867 		BT_ERR("Failed to allocate memory for baudrate packet");
868 		return -ENOMEM;
869 	}
870 
871 	/* Assign commands to change baudrate and packet type. */
872 	skb_put_data(skb, cmd, sizeof(cmd));
873 	hci_skb_pkt_type(skb) = HCI_COMMAND_PKT;
874 
875 	skb_queue_tail(&qca->txq, skb);
876 	hci_uart_tx_wakeup(hu);
877 
878 	/* wait 300ms to change new baudrate on controller side
879 	 * controller will come back after they receive this HCI command
880 	 * then host can communicate with new baudrate to controller
881 	 */
882 	set_current_state(TASK_UNINTERRUPTIBLE);
883 	schedule_timeout(msecs_to_jiffies(BAUDRATE_SETTLE_TIMEOUT_MS));
884 	set_current_state(TASK_INTERRUPTIBLE);
885 
886 	return 0;
887 }
888 
889 static int qca_setup(struct hci_uart *hu)
890 {
891 	struct hci_dev *hdev = hu->hdev;
892 	struct qca_data *qca = hu->priv;
893 	unsigned int speed, qca_baudrate = QCA_BAUDRATE_115200;
894 	int ret;
895 
896 	BT_INFO("%s: ROME setup", hdev->name);
897 
898 	/* Patch downloading has to be done without IBS mode */
899 	clear_bit(STATE_IN_BAND_SLEEP_ENABLED, &qca->flags);
900 
901 	/* Setup initial baudrate */
902 	speed = 0;
903 	if (hu->init_speed)
904 		speed = hu->init_speed;
905 	else if (hu->proto->init_speed)
906 		speed = hu->proto->init_speed;
907 
908 	if (speed)
909 		hci_uart_set_baudrate(hu, speed);
910 
911 	/* Setup user speed if needed */
912 	speed = 0;
913 	if (hu->oper_speed)
914 		speed = hu->oper_speed;
915 	else if (hu->proto->oper_speed)
916 		speed = hu->proto->oper_speed;
917 
918 	if (speed) {
919 		qca_baudrate = qca_get_baudrate_value(speed);
920 
921 		BT_INFO("%s: Set UART speed to %d", hdev->name, speed);
922 		ret = qca_set_baudrate(hdev, qca_baudrate);
923 		if (ret) {
924 			BT_ERR("%s: Failed to change the baud rate (%d)",
925 			       hdev->name, ret);
926 			return ret;
927 		}
928 		hci_uart_set_baudrate(hu, speed);
929 	}
930 
931 	/* Setup patch / NVM configurations */
932 	ret = qca_uart_setup_rome(hdev, qca_baudrate);
933 	if (!ret) {
934 		set_bit(STATE_IN_BAND_SLEEP_ENABLED, &qca->flags);
935 		qca_debugfs_init(hdev);
936 	}
937 
938 	/* Setup bdaddr */
939 	hu->hdev->set_bdaddr = qca_set_bdaddr_rome;
940 
941 	return ret;
942 }
943 
944 static struct hci_uart_proto qca_proto = {
945 	.id		= HCI_UART_QCA,
946 	.name		= "QCA",
947 	.manufacturer	= 29,
948 	.init_speed	= 115200,
949 	.oper_speed	= 3000000,
950 	.open		= qca_open,
951 	.close		= qca_close,
952 	.flush		= qca_flush,
953 	.setup		= qca_setup,
954 	.recv		= qca_recv,
955 	.enqueue	= qca_enqueue,
956 	.dequeue	= qca_dequeue,
957 };
958 
959 int __init qca_init(void)
960 {
961 	return hci_uart_register_proto(&qca_proto);
962 }
963 
964 int __exit qca_deinit(void)
965 {
966 	return hci_uart_unregister_proto(&qca_proto);
967 }
968