xref: /linux/drivers/bluetooth/hci_qca.c (revision 791d3ef2e11100449837dc0b6fe884e60ca3a484)
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/clk.h>
33 #include <linux/debugfs.h>
34 #include <linux/gpio/consumer.h>
35 #include <linux/mod_devicetable.h>
36 #include <linux/module.h>
37 #include <linux/serdev.h>
38 
39 #include <net/bluetooth/bluetooth.h>
40 #include <net/bluetooth/hci_core.h>
41 
42 #include "hci_uart.h"
43 #include "btqca.h"
44 
45 /* HCI_IBS protocol messages */
46 #define HCI_IBS_SLEEP_IND	0xFE
47 #define HCI_IBS_WAKE_IND	0xFD
48 #define HCI_IBS_WAKE_ACK	0xFC
49 #define HCI_MAX_IBS_SIZE	10
50 
51 /* Controller states */
52 #define STATE_IN_BAND_SLEEP_ENABLED	1
53 
54 #define IBS_WAKE_RETRANS_TIMEOUT_MS	100
55 #define IBS_TX_IDLE_TIMEOUT_MS		2000
56 #define BAUDRATE_SETTLE_TIMEOUT_MS	300
57 
58 /* susclk rate */
59 #define SUSCLK_RATE_32KHZ	32768
60 
61 /* HCI_IBS transmit side sleep protocol states */
62 enum tx_ibs_states {
63 	HCI_IBS_TX_ASLEEP,
64 	HCI_IBS_TX_WAKING,
65 	HCI_IBS_TX_AWAKE,
66 };
67 
68 /* HCI_IBS receive side sleep protocol states */
69 enum rx_states {
70 	HCI_IBS_RX_ASLEEP,
71 	HCI_IBS_RX_AWAKE,
72 };
73 
74 /* HCI_IBS transmit and receive side clock state vote */
75 enum hci_ibs_clock_state_vote {
76 	HCI_IBS_VOTE_STATS_UPDATE,
77 	HCI_IBS_TX_VOTE_CLOCK_ON,
78 	HCI_IBS_TX_VOTE_CLOCK_OFF,
79 	HCI_IBS_RX_VOTE_CLOCK_ON,
80 	HCI_IBS_RX_VOTE_CLOCK_OFF,
81 };
82 
83 struct qca_data {
84 	struct hci_uart *hu;
85 	struct sk_buff *rx_skb;
86 	struct sk_buff_head txq;
87 	struct sk_buff_head tx_wait_q;	/* HCI_IBS wait queue	*/
88 	spinlock_t hci_ibs_lock;	/* HCI_IBS state lock	*/
89 	u8 tx_ibs_state;	/* HCI_IBS transmit side power state*/
90 	u8 rx_ibs_state;	/* HCI_IBS receive side power state */
91 	bool tx_vote;		/* Clock must be on for TX */
92 	bool rx_vote;		/* Clock must be on for RX */
93 	struct timer_list tx_idle_timer;
94 	u32 tx_idle_delay;
95 	struct timer_list wake_retrans_timer;
96 	u32 wake_retrans;
97 	struct workqueue_struct *workqueue;
98 	struct work_struct ws_awake_rx;
99 	struct work_struct ws_awake_device;
100 	struct work_struct ws_rx_vote_off;
101 	struct work_struct ws_tx_vote_off;
102 	unsigned long flags;
103 
104 	/* For debugging purpose */
105 	u64 ibs_sent_wacks;
106 	u64 ibs_sent_slps;
107 	u64 ibs_sent_wakes;
108 	u64 ibs_recv_wacks;
109 	u64 ibs_recv_slps;
110 	u64 ibs_recv_wakes;
111 	u64 vote_last_jif;
112 	u32 vote_on_ms;
113 	u32 vote_off_ms;
114 	u64 tx_votes_on;
115 	u64 rx_votes_on;
116 	u64 tx_votes_off;
117 	u64 rx_votes_off;
118 	u64 votes_on;
119 	u64 votes_off;
120 };
121 
122 struct qca_serdev {
123 	struct hci_uart	 serdev_hu;
124 	struct gpio_desc *bt_en;
125 	struct clk	 *susclk;
126 };
127 
128 static void __serial_clock_on(struct tty_struct *tty)
129 {
130 	/* TODO: Some chipset requires to enable UART clock on client
131 	 * side to save power consumption or manual work is required.
132 	 * Please put your code to control UART clock here if needed
133 	 */
134 }
135 
136 static void __serial_clock_off(struct tty_struct *tty)
137 {
138 	/* TODO: Some chipset requires to disable UART clock on client
139 	 * side to save power consumption or manual work is required.
140 	 * Please put your code to control UART clock off here if needed
141 	 */
142 }
143 
144 /* serial_clock_vote needs to be called with the ibs lock held */
145 static void serial_clock_vote(unsigned long vote, struct hci_uart *hu)
146 {
147 	struct qca_data *qca = hu->priv;
148 	unsigned int diff;
149 
150 	bool old_vote = (qca->tx_vote | qca->rx_vote);
151 	bool new_vote;
152 
153 	switch (vote) {
154 	case HCI_IBS_VOTE_STATS_UPDATE:
155 		diff = jiffies_to_msecs(jiffies - qca->vote_last_jif);
156 
157 		if (old_vote)
158 			qca->vote_off_ms += diff;
159 		else
160 			qca->vote_on_ms += diff;
161 		return;
162 
163 	case HCI_IBS_TX_VOTE_CLOCK_ON:
164 		qca->tx_vote = true;
165 		qca->tx_votes_on++;
166 		new_vote = true;
167 		break;
168 
169 	case HCI_IBS_RX_VOTE_CLOCK_ON:
170 		qca->rx_vote = true;
171 		qca->rx_votes_on++;
172 		new_vote = true;
173 		break;
174 
175 	case HCI_IBS_TX_VOTE_CLOCK_OFF:
176 		qca->tx_vote = false;
177 		qca->tx_votes_off++;
178 		new_vote = qca->rx_vote | qca->tx_vote;
179 		break;
180 
181 	case HCI_IBS_RX_VOTE_CLOCK_OFF:
182 		qca->rx_vote = false;
183 		qca->rx_votes_off++;
184 		new_vote = qca->rx_vote | qca->tx_vote;
185 		break;
186 
187 	default:
188 		BT_ERR("Voting irregularity");
189 		return;
190 	}
191 
192 	if (new_vote != old_vote) {
193 		if (new_vote)
194 			__serial_clock_on(hu->tty);
195 		else
196 			__serial_clock_off(hu->tty);
197 
198 		BT_DBG("Vote serial clock %s(%s)", new_vote ? "true" : "false",
199 		       vote ? "true" : "false");
200 
201 		diff = jiffies_to_msecs(jiffies - qca->vote_last_jif);
202 
203 		if (new_vote) {
204 			qca->votes_on++;
205 			qca->vote_off_ms += diff;
206 		} else {
207 			qca->votes_off++;
208 			qca->vote_on_ms += diff;
209 		}
210 		qca->vote_last_jif = jiffies;
211 	}
212 }
213 
214 /* Builds and sends an HCI_IBS command packet.
215  * These are very simple packets with only 1 cmd byte.
216  */
217 static int send_hci_ibs_cmd(u8 cmd, struct hci_uart *hu)
218 {
219 	int err = 0;
220 	struct sk_buff *skb = NULL;
221 	struct qca_data *qca = hu->priv;
222 
223 	BT_DBG("hu %p send hci ibs cmd 0x%x", hu, cmd);
224 
225 	skb = bt_skb_alloc(1, GFP_ATOMIC);
226 	if (!skb) {
227 		BT_ERR("Failed to allocate memory for HCI_IBS packet");
228 		return -ENOMEM;
229 	}
230 
231 	/* Assign HCI_IBS type */
232 	skb_put_u8(skb, cmd);
233 
234 	skb_queue_tail(&qca->txq, skb);
235 
236 	return err;
237 }
238 
239 static void qca_wq_awake_device(struct work_struct *work)
240 {
241 	struct qca_data *qca = container_of(work, struct qca_data,
242 					    ws_awake_device);
243 	struct hci_uart *hu = qca->hu;
244 	unsigned long retrans_delay;
245 
246 	BT_DBG("hu %p wq awake device", hu);
247 
248 	/* Vote for serial clock */
249 	serial_clock_vote(HCI_IBS_TX_VOTE_CLOCK_ON, hu);
250 
251 	spin_lock(&qca->hci_ibs_lock);
252 
253 	/* Send wake indication to device */
254 	if (send_hci_ibs_cmd(HCI_IBS_WAKE_IND, hu) < 0)
255 		BT_ERR("Failed to send WAKE to device");
256 
257 	qca->ibs_sent_wakes++;
258 
259 	/* Start retransmit timer */
260 	retrans_delay = msecs_to_jiffies(qca->wake_retrans);
261 	mod_timer(&qca->wake_retrans_timer, jiffies + retrans_delay);
262 
263 	spin_unlock(&qca->hci_ibs_lock);
264 
265 	/* Actually send the packets */
266 	hci_uart_tx_wakeup(hu);
267 }
268 
269 static void qca_wq_awake_rx(struct work_struct *work)
270 {
271 	struct qca_data *qca = container_of(work, struct qca_data,
272 					    ws_awake_rx);
273 	struct hci_uart *hu = qca->hu;
274 
275 	BT_DBG("hu %p wq awake rx", hu);
276 
277 	serial_clock_vote(HCI_IBS_RX_VOTE_CLOCK_ON, hu);
278 
279 	spin_lock(&qca->hci_ibs_lock);
280 	qca->rx_ibs_state = HCI_IBS_RX_AWAKE;
281 
282 	/* Always acknowledge device wake up,
283 	 * sending IBS message doesn't count as TX ON.
284 	 */
285 	if (send_hci_ibs_cmd(HCI_IBS_WAKE_ACK, hu) < 0)
286 		BT_ERR("Failed to acknowledge device wake up");
287 
288 	qca->ibs_sent_wacks++;
289 
290 	spin_unlock(&qca->hci_ibs_lock);
291 
292 	/* Actually send the packets */
293 	hci_uart_tx_wakeup(hu);
294 }
295 
296 static void qca_wq_serial_rx_clock_vote_off(struct work_struct *work)
297 {
298 	struct qca_data *qca = container_of(work, struct qca_data,
299 					    ws_rx_vote_off);
300 	struct hci_uart *hu = qca->hu;
301 
302 	BT_DBG("hu %p rx clock vote off", hu);
303 
304 	serial_clock_vote(HCI_IBS_RX_VOTE_CLOCK_OFF, hu);
305 }
306 
307 static void qca_wq_serial_tx_clock_vote_off(struct work_struct *work)
308 {
309 	struct qca_data *qca = container_of(work, struct qca_data,
310 					    ws_tx_vote_off);
311 	struct hci_uart *hu = qca->hu;
312 
313 	BT_DBG("hu %p tx clock vote off", hu);
314 
315 	/* Run HCI tx handling unlocked */
316 	hci_uart_tx_wakeup(hu);
317 
318 	/* Now that message queued to tty driver, vote for tty clocks off.
319 	 * It is up to the tty driver to pend the clocks off until tx done.
320 	 */
321 	serial_clock_vote(HCI_IBS_TX_VOTE_CLOCK_OFF, hu);
322 }
323 
324 static void hci_ibs_tx_idle_timeout(struct timer_list *t)
325 {
326 	struct qca_data *qca = from_timer(qca, t, tx_idle_timer);
327 	struct hci_uart *hu = qca->hu;
328 	unsigned long flags;
329 
330 	BT_DBG("hu %p idle timeout in %d state", hu, qca->tx_ibs_state);
331 
332 	spin_lock_irqsave_nested(&qca->hci_ibs_lock,
333 				 flags, SINGLE_DEPTH_NESTING);
334 
335 	switch (qca->tx_ibs_state) {
336 	case HCI_IBS_TX_AWAKE:
337 		/* TX_IDLE, go to SLEEP */
338 		if (send_hci_ibs_cmd(HCI_IBS_SLEEP_IND, hu) < 0) {
339 			BT_ERR("Failed to send SLEEP to device");
340 			break;
341 		}
342 		qca->tx_ibs_state = HCI_IBS_TX_ASLEEP;
343 		qca->ibs_sent_slps++;
344 		queue_work(qca->workqueue, &qca->ws_tx_vote_off);
345 		break;
346 
347 	case HCI_IBS_TX_ASLEEP:
348 	case HCI_IBS_TX_WAKING:
349 		/* Fall through */
350 
351 	default:
352 		BT_ERR("Spurious timeout tx state %d", qca->tx_ibs_state);
353 		break;
354 	}
355 
356 	spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
357 }
358 
359 static void hci_ibs_wake_retrans_timeout(struct timer_list *t)
360 {
361 	struct qca_data *qca = from_timer(qca, t, wake_retrans_timer);
362 	struct hci_uart *hu = qca->hu;
363 	unsigned long flags, retrans_delay;
364 	bool retransmit = false;
365 
366 	BT_DBG("hu %p wake retransmit timeout in %d state",
367 		hu, qca->tx_ibs_state);
368 
369 	spin_lock_irqsave_nested(&qca->hci_ibs_lock,
370 				 flags, SINGLE_DEPTH_NESTING);
371 
372 	switch (qca->tx_ibs_state) {
373 	case HCI_IBS_TX_WAKING:
374 		/* No WAKE_ACK, retransmit WAKE */
375 		retransmit = true;
376 		if (send_hci_ibs_cmd(HCI_IBS_WAKE_IND, hu) < 0) {
377 			BT_ERR("Failed to acknowledge device wake up");
378 			break;
379 		}
380 		qca->ibs_sent_wakes++;
381 		retrans_delay = msecs_to_jiffies(qca->wake_retrans);
382 		mod_timer(&qca->wake_retrans_timer, jiffies + retrans_delay);
383 		break;
384 
385 	case HCI_IBS_TX_ASLEEP:
386 	case HCI_IBS_TX_AWAKE:
387 		/* Fall through */
388 
389 	default:
390 		BT_ERR("Spurious timeout tx state %d", qca->tx_ibs_state);
391 		break;
392 	}
393 
394 	spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
395 
396 	if (retransmit)
397 		hci_uart_tx_wakeup(hu);
398 }
399 
400 /* Initialize protocol */
401 static int qca_open(struct hci_uart *hu)
402 {
403 	struct qca_serdev *qcadev;
404 	struct qca_data *qca;
405 
406 	BT_DBG("hu %p qca_open", hu);
407 
408 	qca = kzalloc(sizeof(struct qca_data), GFP_ATOMIC);
409 	if (!qca)
410 		return -ENOMEM;
411 
412 	skb_queue_head_init(&qca->txq);
413 	skb_queue_head_init(&qca->tx_wait_q);
414 	spin_lock_init(&qca->hci_ibs_lock);
415 	qca->workqueue = alloc_ordered_workqueue("qca_wq", 0);
416 	if (!qca->workqueue) {
417 		BT_ERR("QCA Workqueue not initialized properly");
418 		kfree(qca);
419 		return -ENOMEM;
420 	}
421 
422 	INIT_WORK(&qca->ws_awake_rx, qca_wq_awake_rx);
423 	INIT_WORK(&qca->ws_awake_device, qca_wq_awake_device);
424 	INIT_WORK(&qca->ws_rx_vote_off, qca_wq_serial_rx_clock_vote_off);
425 	INIT_WORK(&qca->ws_tx_vote_off, qca_wq_serial_tx_clock_vote_off);
426 
427 	qca->hu = hu;
428 
429 	/* Assume we start with both sides asleep -- extra wakes OK */
430 	qca->tx_ibs_state = HCI_IBS_TX_ASLEEP;
431 	qca->rx_ibs_state = HCI_IBS_RX_ASLEEP;
432 
433 	/* clocks actually on, but we start votes off */
434 	qca->tx_vote = false;
435 	qca->rx_vote = false;
436 	qca->flags = 0;
437 
438 	qca->ibs_sent_wacks = 0;
439 	qca->ibs_sent_slps = 0;
440 	qca->ibs_sent_wakes = 0;
441 	qca->ibs_recv_wacks = 0;
442 	qca->ibs_recv_slps = 0;
443 	qca->ibs_recv_wakes = 0;
444 	qca->vote_last_jif = jiffies;
445 	qca->vote_on_ms = 0;
446 	qca->vote_off_ms = 0;
447 	qca->votes_on = 0;
448 	qca->votes_off = 0;
449 	qca->tx_votes_on = 0;
450 	qca->tx_votes_off = 0;
451 	qca->rx_votes_on = 0;
452 	qca->rx_votes_off = 0;
453 
454 	hu->priv = qca;
455 
456 	timer_setup(&qca->wake_retrans_timer, hci_ibs_wake_retrans_timeout, 0);
457 	qca->wake_retrans = IBS_WAKE_RETRANS_TIMEOUT_MS;
458 
459 	timer_setup(&qca->tx_idle_timer, hci_ibs_tx_idle_timeout, 0);
460 	qca->tx_idle_delay = IBS_TX_IDLE_TIMEOUT_MS;
461 
462 	if (hu->serdev) {
463 		serdev_device_open(hu->serdev);
464 
465 		qcadev = serdev_device_get_drvdata(hu->serdev);
466 		gpiod_set_value_cansleep(qcadev->bt_en, 1);
467 	}
468 
469 	BT_DBG("HCI_UART_QCA open, tx_idle_delay=%u, wake_retrans=%u",
470 	       qca->tx_idle_delay, qca->wake_retrans);
471 
472 	return 0;
473 }
474 
475 static void qca_debugfs_init(struct hci_dev *hdev)
476 {
477 	struct hci_uart *hu = hci_get_drvdata(hdev);
478 	struct qca_data *qca = hu->priv;
479 	struct dentry *ibs_dir;
480 	umode_t mode;
481 
482 	if (!hdev->debugfs)
483 		return;
484 
485 	ibs_dir = debugfs_create_dir("ibs", hdev->debugfs);
486 
487 	/* read only */
488 	mode = S_IRUGO;
489 	debugfs_create_u8("tx_ibs_state", mode, ibs_dir, &qca->tx_ibs_state);
490 	debugfs_create_u8("rx_ibs_state", mode, ibs_dir, &qca->rx_ibs_state);
491 	debugfs_create_u64("ibs_sent_sleeps", mode, ibs_dir,
492 			   &qca->ibs_sent_slps);
493 	debugfs_create_u64("ibs_sent_wakes", mode, ibs_dir,
494 			   &qca->ibs_sent_wakes);
495 	debugfs_create_u64("ibs_sent_wake_acks", mode, ibs_dir,
496 			   &qca->ibs_sent_wacks);
497 	debugfs_create_u64("ibs_recv_sleeps", mode, ibs_dir,
498 			   &qca->ibs_recv_slps);
499 	debugfs_create_u64("ibs_recv_wakes", mode, ibs_dir,
500 			   &qca->ibs_recv_wakes);
501 	debugfs_create_u64("ibs_recv_wake_acks", mode, ibs_dir,
502 			   &qca->ibs_recv_wacks);
503 	debugfs_create_bool("tx_vote", mode, ibs_dir, &qca->tx_vote);
504 	debugfs_create_u64("tx_votes_on", mode, ibs_dir, &qca->tx_votes_on);
505 	debugfs_create_u64("tx_votes_off", mode, ibs_dir, &qca->tx_votes_off);
506 	debugfs_create_bool("rx_vote", mode, ibs_dir, &qca->rx_vote);
507 	debugfs_create_u64("rx_votes_on", mode, ibs_dir, &qca->rx_votes_on);
508 	debugfs_create_u64("rx_votes_off", mode, ibs_dir, &qca->rx_votes_off);
509 	debugfs_create_u64("votes_on", mode, ibs_dir, &qca->votes_on);
510 	debugfs_create_u64("votes_off", mode, ibs_dir, &qca->votes_off);
511 	debugfs_create_u32("vote_on_ms", mode, ibs_dir, &qca->vote_on_ms);
512 	debugfs_create_u32("vote_off_ms", mode, ibs_dir, &qca->vote_off_ms);
513 
514 	/* read/write */
515 	mode = S_IRUGO | S_IWUSR;
516 	debugfs_create_u32("wake_retrans", mode, ibs_dir, &qca->wake_retrans);
517 	debugfs_create_u32("tx_idle_delay", mode, ibs_dir,
518 			   &qca->tx_idle_delay);
519 }
520 
521 /* Flush protocol data */
522 static int qca_flush(struct hci_uart *hu)
523 {
524 	struct qca_data *qca = hu->priv;
525 
526 	BT_DBG("hu %p qca flush", hu);
527 
528 	skb_queue_purge(&qca->tx_wait_q);
529 	skb_queue_purge(&qca->txq);
530 
531 	return 0;
532 }
533 
534 /* Close protocol */
535 static int qca_close(struct hci_uart *hu)
536 {
537 	struct qca_serdev *qcadev;
538 	struct qca_data *qca = hu->priv;
539 
540 	BT_DBG("hu %p qca close", hu);
541 
542 	serial_clock_vote(HCI_IBS_VOTE_STATS_UPDATE, hu);
543 
544 	skb_queue_purge(&qca->tx_wait_q);
545 	skb_queue_purge(&qca->txq);
546 	del_timer(&qca->tx_idle_timer);
547 	del_timer(&qca->wake_retrans_timer);
548 	destroy_workqueue(qca->workqueue);
549 	qca->hu = NULL;
550 
551 	if (hu->serdev) {
552 		serdev_device_close(hu->serdev);
553 
554 		qcadev = serdev_device_get_drvdata(hu->serdev);
555 		gpiod_set_value_cansleep(qcadev->bt_en, 0);
556 	}
557 
558 	kfree_skb(qca->rx_skb);
559 
560 	hu->priv = NULL;
561 
562 	kfree(qca);
563 
564 	return 0;
565 }
566 
567 /* Called upon a wake-up-indication from the device.
568  */
569 static void device_want_to_wakeup(struct hci_uart *hu)
570 {
571 	unsigned long flags;
572 	struct qca_data *qca = hu->priv;
573 
574 	BT_DBG("hu %p want to wake up", hu);
575 
576 	spin_lock_irqsave(&qca->hci_ibs_lock, flags);
577 
578 	qca->ibs_recv_wakes++;
579 
580 	switch (qca->rx_ibs_state) {
581 	case HCI_IBS_RX_ASLEEP:
582 		/* Make sure clock is on - we may have turned clock off since
583 		 * receiving the wake up indicator awake rx clock.
584 		 */
585 		queue_work(qca->workqueue, &qca->ws_awake_rx);
586 		spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
587 		return;
588 
589 	case HCI_IBS_RX_AWAKE:
590 		/* Always acknowledge device wake up,
591 		 * sending IBS message doesn't count as TX ON.
592 		 */
593 		if (send_hci_ibs_cmd(HCI_IBS_WAKE_ACK, hu) < 0) {
594 			BT_ERR("Failed to acknowledge device wake up");
595 			break;
596 		}
597 		qca->ibs_sent_wacks++;
598 		break;
599 
600 	default:
601 		/* Any other state is illegal */
602 		BT_ERR("Received HCI_IBS_WAKE_IND in rx state %d",
603 		       qca->rx_ibs_state);
604 		break;
605 	}
606 
607 	spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
608 
609 	/* Actually send the packets */
610 	hci_uart_tx_wakeup(hu);
611 }
612 
613 /* Called upon a sleep-indication from the device.
614  */
615 static void device_want_to_sleep(struct hci_uart *hu)
616 {
617 	unsigned long flags;
618 	struct qca_data *qca = hu->priv;
619 
620 	BT_DBG("hu %p want to sleep", hu);
621 
622 	spin_lock_irqsave(&qca->hci_ibs_lock, flags);
623 
624 	qca->ibs_recv_slps++;
625 
626 	switch (qca->rx_ibs_state) {
627 	case HCI_IBS_RX_AWAKE:
628 		/* Update state */
629 		qca->rx_ibs_state = HCI_IBS_RX_ASLEEP;
630 		/* Vote off rx clock under workqueue */
631 		queue_work(qca->workqueue, &qca->ws_rx_vote_off);
632 		break;
633 
634 	case HCI_IBS_RX_ASLEEP:
635 		/* Fall through */
636 
637 	default:
638 		/* Any other state is illegal */
639 		BT_ERR("Received HCI_IBS_SLEEP_IND in rx state %d",
640 		       qca->rx_ibs_state);
641 		break;
642 	}
643 
644 	spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
645 }
646 
647 /* Called upon wake-up-acknowledgement from the device
648  */
649 static void device_woke_up(struct hci_uart *hu)
650 {
651 	unsigned long flags, idle_delay;
652 	struct qca_data *qca = hu->priv;
653 	struct sk_buff *skb = NULL;
654 
655 	BT_DBG("hu %p woke up", hu);
656 
657 	spin_lock_irqsave(&qca->hci_ibs_lock, flags);
658 
659 	qca->ibs_recv_wacks++;
660 
661 	switch (qca->tx_ibs_state) {
662 	case HCI_IBS_TX_AWAKE:
663 		/* Expect one if we send 2 WAKEs */
664 		BT_DBG("Received HCI_IBS_WAKE_ACK in tx state %d",
665 		       qca->tx_ibs_state);
666 		break;
667 
668 	case HCI_IBS_TX_WAKING:
669 		/* Send pending packets */
670 		while ((skb = skb_dequeue(&qca->tx_wait_q)))
671 			skb_queue_tail(&qca->txq, skb);
672 
673 		/* Switch timers and change state to HCI_IBS_TX_AWAKE */
674 		del_timer(&qca->wake_retrans_timer);
675 		idle_delay = msecs_to_jiffies(qca->tx_idle_delay);
676 		mod_timer(&qca->tx_idle_timer, jiffies + idle_delay);
677 		qca->tx_ibs_state = HCI_IBS_TX_AWAKE;
678 		break;
679 
680 	case HCI_IBS_TX_ASLEEP:
681 		/* Fall through */
682 
683 	default:
684 		BT_ERR("Received HCI_IBS_WAKE_ACK in tx state %d",
685 		       qca->tx_ibs_state);
686 		break;
687 	}
688 
689 	spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
690 
691 	/* Actually send the packets */
692 	hci_uart_tx_wakeup(hu);
693 }
694 
695 /* Enqueue frame for transmittion (padding, crc, etc) may be called from
696  * two simultaneous tasklets.
697  */
698 static int qca_enqueue(struct hci_uart *hu, struct sk_buff *skb)
699 {
700 	unsigned long flags = 0, idle_delay;
701 	struct qca_data *qca = hu->priv;
702 
703 	BT_DBG("hu %p qca enq skb %p tx_ibs_state %d", hu, skb,
704 	       qca->tx_ibs_state);
705 
706 	/* Prepend skb with frame type */
707 	memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
708 
709 	/* Don't go to sleep in middle of patch download or
710 	 * Out-Of-Band(GPIOs control) sleep is selected.
711 	 */
712 	if (!test_bit(STATE_IN_BAND_SLEEP_ENABLED, &qca->flags)) {
713 		skb_queue_tail(&qca->txq, skb);
714 		return 0;
715 	}
716 
717 	spin_lock_irqsave(&qca->hci_ibs_lock, flags);
718 
719 	/* Act according to current state */
720 	switch (qca->tx_ibs_state) {
721 	case HCI_IBS_TX_AWAKE:
722 		BT_DBG("Device awake, sending normally");
723 		skb_queue_tail(&qca->txq, skb);
724 		idle_delay = msecs_to_jiffies(qca->tx_idle_delay);
725 		mod_timer(&qca->tx_idle_timer, jiffies + idle_delay);
726 		break;
727 
728 	case HCI_IBS_TX_ASLEEP:
729 		BT_DBG("Device asleep, waking up and queueing packet");
730 		/* Save packet for later */
731 		skb_queue_tail(&qca->tx_wait_q, skb);
732 
733 		qca->tx_ibs_state = HCI_IBS_TX_WAKING;
734 		/* Schedule a work queue to wake up device */
735 		queue_work(qca->workqueue, &qca->ws_awake_device);
736 		break;
737 
738 	case HCI_IBS_TX_WAKING:
739 		BT_DBG("Device waking up, queueing packet");
740 		/* Transient state; just keep packet for later */
741 		skb_queue_tail(&qca->tx_wait_q, skb);
742 		break;
743 
744 	default:
745 		BT_ERR("Illegal tx state: %d (losing packet)",
746 		       qca->tx_ibs_state);
747 		kfree_skb(skb);
748 		break;
749 	}
750 
751 	spin_unlock_irqrestore(&qca->hci_ibs_lock, flags);
752 
753 	return 0;
754 }
755 
756 static int qca_ibs_sleep_ind(struct hci_dev *hdev, struct sk_buff *skb)
757 {
758 	struct hci_uart *hu = hci_get_drvdata(hdev);
759 
760 	BT_DBG("hu %p recv hci ibs cmd 0x%x", hu, HCI_IBS_SLEEP_IND);
761 
762 	device_want_to_sleep(hu);
763 
764 	kfree_skb(skb);
765 	return 0;
766 }
767 
768 static int qca_ibs_wake_ind(struct hci_dev *hdev, struct sk_buff *skb)
769 {
770 	struct hci_uart *hu = hci_get_drvdata(hdev);
771 
772 	BT_DBG("hu %p recv hci ibs cmd 0x%x", hu, HCI_IBS_WAKE_IND);
773 
774 	device_want_to_wakeup(hu);
775 
776 	kfree_skb(skb);
777 	return 0;
778 }
779 
780 static int qca_ibs_wake_ack(struct hci_dev *hdev, struct sk_buff *skb)
781 {
782 	struct hci_uart *hu = hci_get_drvdata(hdev);
783 
784 	BT_DBG("hu %p recv hci ibs cmd 0x%x", hu, HCI_IBS_WAKE_ACK);
785 
786 	device_woke_up(hu);
787 
788 	kfree_skb(skb);
789 	return 0;
790 }
791 
792 #define QCA_IBS_SLEEP_IND_EVENT \
793 	.type = HCI_IBS_SLEEP_IND, \
794 	.hlen = 0, \
795 	.loff = 0, \
796 	.lsize = 0, \
797 	.maxlen = HCI_MAX_IBS_SIZE
798 
799 #define QCA_IBS_WAKE_IND_EVENT \
800 	.type = HCI_IBS_WAKE_IND, \
801 	.hlen = 0, \
802 	.loff = 0, \
803 	.lsize = 0, \
804 	.maxlen = HCI_MAX_IBS_SIZE
805 
806 #define QCA_IBS_WAKE_ACK_EVENT \
807 	.type = HCI_IBS_WAKE_ACK, \
808 	.hlen = 0, \
809 	.loff = 0, \
810 	.lsize = 0, \
811 	.maxlen = HCI_MAX_IBS_SIZE
812 
813 static const struct h4_recv_pkt qca_recv_pkts[] = {
814 	{ H4_RECV_ACL,             .recv = hci_recv_frame    },
815 	{ H4_RECV_SCO,             .recv = hci_recv_frame    },
816 	{ H4_RECV_EVENT,           .recv = hci_recv_frame    },
817 	{ QCA_IBS_WAKE_IND_EVENT,  .recv = qca_ibs_wake_ind  },
818 	{ QCA_IBS_WAKE_ACK_EVENT,  .recv = qca_ibs_wake_ack  },
819 	{ QCA_IBS_SLEEP_IND_EVENT, .recv = qca_ibs_sleep_ind },
820 };
821 
822 static int qca_recv(struct hci_uart *hu, const void *data, int count)
823 {
824 	struct qca_data *qca = hu->priv;
825 
826 	if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
827 		return -EUNATCH;
828 
829 	qca->rx_skb = h4_recv_buf(hu->hdev, qca->rx_skb, data, count,
830 				  qca_recv_pkts, ARRAY_SIZE(qca_recv_pkts));
831 	if (IS_ERR(qca->rx_skb)) {
832 		int err = PTR_ERR(qca->rx_skb);
833 		bt_dev_err(hu->hdev, "Frame reassembly failed (%d)", err);
834 		qca->rx_skb = NULL;
835 		return err;
836 	}
837 
838 	return count;
839 }
840 
841 static struct sk_buff *qca_dequeue(struct hci_uart *hu)
842 {
843 	struct qca_data *qca = hu->priv;
844 
845 	return skb_dequeue(&qca->txq);
846 }
847 
848 static uint8_t qca_get_baudrate_value(int speed)
849 {
850 	switch (speed) {
851 	case 9600:
852 		return QCA_BAUDRATE_9600;
853 	case 19200:
854 		return QCA_BAUDRATE_19200;
855 	case 38400:
856 		return QCA_BAUDRATE_38400;
857 	case 57600:
858 		return QCA_BAUDRATE_57600;
859 	case 115200:
860 		return QCA_BAUDRATE_115200;
861 	case 230400:
862 		return QCA_BAUDRATE_230400;
863 	case 460800:
864 		return QCA_BAUDRATE_460800;
865 	case 500000:
866 		return QCA_BAUDRATE_500000;
867 	case 921600:
868 		return QCA_BAUDRATE_921600;
869 	case 1000000:
870 		return QCA_BAUDRATE_1000000;
871 	case 2000000:
872 		return QCA_BAUDRATE_2000000;
873 	case 3000000:
874 		return QCA_BAUDRATE_3000000;
875 	case 3500000:
876 		return QCA_BAUDRATE_3500000;
877 	default:
878 		return QCA_BAUDRATE_115200;
879 	}
880 }
881 
882 static int qca_set_baudrate(struct hci_dev *hdev, uint8_t baudrate)
883 {
884 	struct hci_uart *hu = hci_get_drvdata(hdev);
885 	struct qca_data *qca = hu->priv;
886 	struct sk_buff *skb;
887 	u8 cmd[] = { 0x01, 0x48, 0xFC, 0x01, 0x00 };
888 
889 	if (baudrate > QCA_BAUDRATE_3000000)
890 		return -EINVAL;
891 
892 	cmd[4] = baudrate;
893 
894 	skb = bt_skb_alloc(sizeof(cmd), GFP_ATOMIC);
895 	if (!skb) {
896 		bt_dev_err(hdev, "Failed to allocate baudrate packet");
897 		return -ENOMEM;
898 	}
899 
900 	/* Assign commands to change baudrate and packet type. */
901 	skb_put_data(skb, cmd, sizeof(cmd));
902 	hci_skb_pkt_type(skb) = HCI_COMMAND_PKT;
903 
904 	skb_queue_tail(&qca->txq, skb);
905 	hci_uart_tx_wakeup(hu);
906 
907 	/* wait 300ms to change new baudrate on controller side
908 	 * controller will come back after they receive this HCI command
909 	 * then host can communicate with new baudrate to controller
910 	 */
911 	set_current_state(TASK_UNINTERRUPTIBLE);
912 	schedule_timeout(msecs_to_jiffies(BAUDRATE_SETTLE_TIMEOUT_MS));
913 	set_current_state(TASK_RUNNING);
914 
915 	return 0;
916 }
917 
918 static inline void host_set_baudrate(struct hci_uart *hu, unsigned int speed)
919 {
920 	if (hu->serdev)
921 		serdev_device_set_baudrate(hu->serdev, speed);
922 	else
923 		hci_uart_set_baudrate(hu, speed);
924 }
925 
926 static int qca_setup(struct hci_uart *hu)
927 {
928 	struct hci_dev *hdev = hu->hdev;
929 	struct qca_data *qca = hu->priv;
930 	unsigned int speed, qca_baudrate = QCA_BAUDRATE_115200;
931 	int ret;
932 
933 	bt_dev_info(hdev, "ROME setup");
934 
935 	/* Patch downloading has to be done without IBS mode */
936 	clear_bit(STATE_IN_BAND_SLEEP_ENABLED, &qca->flags);
937 
938 	/* Setup initial baudrate */
939 	speed = 0;
940 	if (hu->init_speed)
941 		speed = hu->init_speed;
942 	else if (hu->proto->init_speed)
943 		speed = hu->proto->init_speed;
944 
945 	if (speed)
946 		host_set_baudrate(hu, speed);
947 
948 	/* Setup user speed if needed */
949 	speed = 0;
950 	if (hu->oper_speed)
951 		speed = hu->oper_speed;
952 	else if (hu->proto->oper_speed)
953 		speed = hu->proto->oper_speed;
954 
955 	if (speed) {
956 		qca_baudrate = qca_get_baudrate_value(speed);
957 
958 		bt_dev_info(hdev, "Set UART speed to %d", speed);
959 		ret = qca_set_baudrate(hdev, qca_baudrate);
960 		if (ret) {
961 			bt_dev_err(hdev, "Failed to change the baud rate (%d)",
962 				   ret);
963 			return ret;
964 		}
965 		host_set_baudrate(hu, speed);
966 	}
967 
968 	/* Setup patch / NVM configurations */
969 	ret = qca_uart_setup_rome(hdev, qca_baudrate);
970 	if (!ret) {
971 		set_bit(STATE_IN_BAND_SLEEP_ENABLED, &qca->flags);
972 		qca_debugfs_init(hdev);
973 	} else if (ret == -ENOENT) {
974 		/* No patch/nvm-config found, run with original fw/config */
975 		ret = 0;
976 	} else if (ret == -EAGAIN) {
977 		/*
978 		 * Userspace firmware loader will return -EAGAIN in case no
979 		 * patch/nvm-config is found, so run with original fw/config.
980 		 */
981 		ret = 0;
982 	}
983 
984 	/* Setup bdaddr */
985 	hu->hdev->set_bdaddr = qca_set_bdaddr_rome;
986 
987 	return ret;
988 }
989 
990 static struct hci_uart_proto qca_proto = {
991 	.id		= HCI_UART_QCA,
992 	.name		= "QCA",
993 	.manufacturer	= 29,
994 	.init_speed	= 115200,
995 	.oper_speed	= 3000000,
996 	.open		= qca_open,
997 	.close		= qca_close,
998 	.flush		= qca_flush,
999 	.setup		= qca_setup,
1000 	.recv		= qca_recv,
1001 	.enqueue	= qca_enqueue,
1002 	.dequeue	= qca_dequeue,
1003 };
1004 
1005 static int qca_serdev_probe(struct serdev_device *serdev)
1006 {
1007 	struct qca_serdev *qcadev;
1008 	int err;
1009 
1010 	qcadev = devm_kzalloc(&serdev->dev, sizeof(*qcadev), GFP_KERNEL);
1011 	if (!qcadev)
1012 		return -ENOMEM;
1013 
1014 	qcadev->serdev_hu.serdev = serdev;
1015 	serdev_device_set_drvdata(serdev, qcadev);
1016 
1017 	qcadev->bt_en = devm_gpiod_get(&serdev->dev, "enable",
1018 				       GPIOD_OUT_LOW);
1019 	if (IS_ERR(qcadev->bt_en)) {
1020 		dev_err(&serdev->dev, "failed to acquire enable gpio\n");
1021 		return PTR_ERR(qcadev->bt_en);
1022 	}
1023 
1024 	qcadev->susclk = devm_clk_get(&serdev->dev, NULL);
1025 	if (IS_ERR(qcadev->susclk)) {
1026 		dev_err(&serdev->dev, "failed to acquire clk\n");
1027 		return PTR_ERR(qcadev->susclk);
1028 	}
1029 
1030 	err = clk_set_rate(qcadev->susclk, SUSCLK_RATE_32KHZ);
1031 	if (err)
1032 		return err;
1033 
1034 	err = clk_prepare_enable(qcadev->susclk);
1035 	if (err)
1036 		return err;
1037 
1038 	err = hci_uart_register_device(&qcadev->serdev_hu, &qca_proto);
1039 	if (err)
1040 		clk_disable_unprepare(qcadev->susclk);
1041 
1042 	return err;
1043 }
1044 
1045 static void qca_serdev_remove(struct serdev_device *serdev)
1046 {
1047 	struct qca_serdev *qcadev = serdev_device_get_drvdata(serdev);
1048 
1049 	hci_uart_unregister_device(&qcadev->serdev_hu);
1050 
1051 	clk_disable_unprepare(qcadev->susclk);
1052 }
1053 
1054 static const struct of_device_id qca_bluetooth_of_match[] = {
1055 	{ .compatible = "qcom,qca6174-bt" },
1056 	{ /* sentinel */ }
1057 };
1058 MODULE_DEVICE_TABLE(of, qca_bluetooth_of_match);
1059 
1060 static struct serdev_device_driver qca_serdev_driver = {
1061 	.probe = qca_serdev_probe,
1062 	.remove = qca_serdev_remove,
1063 	.driver = {
1064 		.name = "hci_uart_qca",
1065 		.of_match_table = qca_bluetooth_of_match,
1066 	},
1067 };
1068 
1069 int __init qca_init(void)
1070 {
1071 	serdev_device_driver_register(&qca_serdev_driver);
1072 
1073 	return hci_uart_register_proto(&qca_proto);
1074 }
1075 
1076 int __exit qca_deinit(void)
1077 {
1078 	serdev_device_driver_unregister(&qca_serdev_driver);
1079 
1080 	return hci_uart_unregister_proto(&qca_proto);
1081 }
1082