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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *
4 * Bluetooth HCI Three-wire UART driver
5 *
6 * Copyright (C) 2012 Intel Corporation
7 */
8
9#include <linux/acpi.h>
10#include <linux/errno.h>
11#include <linux/gpio/consumer.h>
12#include <linux/kernel.h>
13#include <linux/mod_devicetable.h>
14#include <linux/of_device.h>
15#include <linux/pm_runtime.h>
16#include <linux/serdev.h>
17#include <linux/skbuff.h>
18
19#include <net/bluetooth/bluetooth.h>
20#include <net/bluetooth/hci_core.h>
21
22#include "btrtl.h"
23#include "hci_uart.h"
24
25#define SUSPEND_TIMEOUT_MS 6000
26
27#define HCI_3WIRE_ACK_PKT 0
28#define HCI_3WIRE_LINK_PKT 15
29
30/* Sliding window size */
31#define H5_TX_WIN_MAX 4
32
33#define H5_ACK_TIMEOUT msecs_to_jiffies(250)
34#define H5_SYNC_TIMEOUT msecs_to_jiffies(100)
35
36/*
37 * Maximum Three-wire packet:
38 * 4 byte header + max value for 12-bit length + 2 bytes for CRC
39 */
40#define H5_MAX_LEN (4 + 0xfff + 2)
41
42/* Convenience macros for reading Three-wire header values */
43#define H5_HDR_SEQ(hdr) ((hdr)[0] & 0x07)
44#define H5_HDR_ACK(hdr) (((hdr)[0] >> 3) & 0x07)
45#define H5_HDR_CRC(hdr) (((hdr)[0] >> 6) & 0x01)
46#define H5_HDR_RELIABLE(hdr) (((hdr)[0] >> 7) & 0x01)
47#define H5_HDR_PKT_TYPE(hdr) ((hdr)[1] & 0x0f)
48#define H5_HDR_LEN(hdr) ((((hdr)[1] >> 4) & 0x0f) + ((hdr)[2] << 4))
49
50#define SLIP_DELIMITER 0xc0
51#define SLIP_ESC 0xdb
52#define SLIP_ESC_DELIM 0xdc
53#define SLIP_ESC_ESC 0xdd
54
55/* H5 state flags */
56enum {
57 H5_RX_ESC, /* SLIP escape mode */
58 H5_TX_ACK_REQ, /* Pending ack to send */
59 H5_WAKEUP_DISABLE, /* Device cannot wake host */
60 H5_HW_FLOW_CONTROL, /* Use HW flow control */
61};
62
63struct h5 {
64 /* Must be the first member, hci_serdev.c expects this. */
65 struct hci_uart serdev_hu;
66
67 struct sk_buff_head unack; /* Unack'ed packets queue */
68 struct sk_buff_head rel; /* Reliable packets queue */
69 struct sk_buff_head unrel; /* Unreliable packets queue */
70
71 unsigned long flags;
72
73 struct sk_buff *rx_skb; /* Receive buffer */
74 size_t rx_pending; /* Expecting more bytes */
75 u8 rx_ack; /* Last ack number received */
76
77 int (*rx_func)(struct hci_uart *hu, u8 c);
78
79 struct timer_list timer; /* Retransmission timer */
80 struct hci_uart *hu; /* Parent HCI UART */
81
82 u8 tx_seq; /* Next seq number to send */
83 u8 tx_ack; /* Next ack number to send */
84 u8 tx_win; /* Sliding window size */
85
86 enum {
87 H5_UNINITIALIZED,
88 H5_INITIALIZED,
89 H5_ACTIVE,
90 } state;
91
92 enum {
93 H5_AWAKE,
94 H5_SLEEPING,
95 H5_WAKING_UP,
96 } sleep;
97
98 const struct h5_vnd *vnd;
99 const char *id;
100
101 struct gpio_desc *enable_gpio;
102 struct gpio_desc *device_wake_gpio;
103};
104
105enum h5_driver_info {
106 H5_INFO_WAKEUP_DISABLE = BIT(0),
107};
108
109struct h5_vnd {
110 int (*setup)(struct h5 *h5);
111 void (*open)(struct h5 *h5);
112 void (*close)(struct h5 *h5);
113 int (*suspend)(struct h5 *h5);
114 int (*resume)(struct h5 *h5);
115 const struct acpi_gpio_mapping *acpi_gpio_map;
116};
117
118struct h5_device_data {
119 uint32_t driver_info;
120 struct h5_vnd *vnd;
121};
122
123static void h5_reset_rx(struct h5 *h5);
124
125static void h5_link_control(struct hci_uart *hu, const void *data, size_t len)
126{
127 struct h5 *h5 = hu->priv;
128 struct sk_buff *nskb;
129
130 nskb = alloc_skb(3, GFP_ATOMIC);
131 if (!nskb)
132 return;
133
134 hci_skb_pkt_type(nskb) = HCI_3WIRE_LINK_PKT;
135
136 skb_put_data(nskb, data, len);
137
138 skb_queue_tail(&h5->unrel, nskb);
139}
140
141static u8 h5_cfg_field(struct h5 *h5)
142{
143 /* Sliding window size (first 3 bits) */
144 return h5->tx_win & 0x07;
145}
146
147static void h5_timed_event(struct timer_list *t)
148{
149 const unsigned char sync_req[] = { 0x01, 0x7e };
150 unsigned char conf_req[3] = { 0x03, 0xfc };
151 struct h5 *h5 = from_timer(h5, t, timer);
152 struct hci_uart *hu = h5->hu;
153 struct sk_buff *skb;
154 unsigned long flags;
155
156 BT_DBG("%s", hu->hdev->name);
157
158 if (h5->state == H5_UNINITIALIZED)
159 h5_link_control(hu, sync_req, sizeof(sync_req));
160
161 if (h5->state == H5_INITIALIZED) {
162 conf_req[2] = h5_cfg_field(h5);
163 h5_link_control(hu, conf_req, sizeof(conf_req));
164 }
165
166 if (h5->state != H5_ACTIVE) {
167 mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT);
168 goto wakeup;
169 }
170
171 if (h5->sleep != H5_AWAKE) {
172 h5->sleep = H5_SLEEPING;
173 goto wakeup;
174 }
175
176 BT_DBG("hu %p retransmitting %u pkts", hu, h5->unack.qlen);
177
178 spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);
179
180 while ((skb = __skb_dequeue_tail(&h5->unack)) != NULL) {
181 h5->tx_seq = (h5->tx_seq - 1) & 0x07;
182 skb_queue_head(&h5->rel, skb);
183 }
184
185 spin_unlock_irqrestore(&h5->unack.lock, flags);
186
187wakeup:
188 hci_uart_tx_wakeup(hu);
189}
190
191static void h5_peer_reset(struct hci_uart *hu)
192{
193 struct h5 *h5 = hu->priv;
194
195 bt_dev_err(hu->hdev, "Peer device has reset");
196
197 h5->state = H5_UNINITIALIZED;
198
199 del_timer(&h5->timer);
200
201 skb_queue_purge(&h5->rel);
202 skb_queue_purge(&h5->unrel);
203 skb_queue_purge(&h5->unack);
204
205 h5->tx_seq = 0;
206 h5->tx_ack = 0;
207
208 /* Send reset request to upper stack */
209 hci_reset_dev(hu->hdev);
210}
211
212static int h5_open(struct hci_uart *hu)
213{
214 struct h5 *h5;
215 const unsigned char sync[] = { 0x01, 0x7e };
216
217 BT_DBG("hu %p", hu);
218
219 if (hu->serdev) {
220 h5 = serdev_device_get_drvdata(hu->serdev);
221 } else {
222 h5 = kzalloc(sizeof(*h5), GFP_KERNEL);
223 if (!h5)
224 return -ENOMEM;
225 }
226
227 hu->priv = h5;
228 h5->hu = hu;
229
230 skb_queue_head_init(&h5->unack);
231 skb_queue_head_init(&h5->rel);
232 skb_queue_head_init(&h5->unrel);
233
234 h5_reset_rx(h5);
235
236 timer_setup(&h5->timer, h5_timed_event, 0);
237
238 h5->tx_win = H5_TX_WIN_MAX;
239
240 if (h5->vnd && h5->vnd->open)
241 h5->vnd->open(h5);
242
243 set_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags);
244
245 /* Send initial sync request */
246 h5_link_control(hu, sync, sizeof(sync));
247 mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT);
248
249 return 0;
250}
251
252static int h5_close(struct hci_uart *hu)
253{
254 struct h5 *h5 = hu->priv;
255
256 del_timer_sync(&h5->timer);
257
258 skb_queue_purge(&h5->unack);
259 skb_queue_purge(&h5->rel);
260 skb_queue_purge(&h5->unrel);
261
262 kfree_skb(h5->rx_skb);
263 h5->rx_skb = NULL;
264
265 if (h5->vnd && h5->vnd->close)
266 h5->vnd->close(h5);
267
268 if (!hu->serdev)
269 kfree(h5);
270
271 return 0;
272}
273
274static int h5_setup(struct hci_uart *hu)
275{
276 struct h5 *h5 = hu->priv;
277
278 if (h5->vnd && h5->vnd->setup)
279 return h5->vnd->setup(h5);
280
281 return 0;
282}
283
284static void h5_pkt_cull(struct h5 *h5)
285{
286 struct sk_buff *skb, *tmp;
287 unsigned long flags;
288 int i, to_remove;
289 u8 seq;
290
291 spin_lock_irqsave(&h5->unack.lock, flags);
292
293 to_remove = skb_queue_len(&h5->unack);
294 if (to_remove == 0)
295 goto unlock;
296
297 seq = h5->tx_seq;
298
299 while (to_remove > 0) {
300 if (h5->rx_ack == seq)
301 break;
302
303 to_remove--;
304 seq = (seq - 1) & 0x07;
305 }
306
307 if (seq != h5->rx_ack)
308 BT_ERR("Controller acked invalid packet");
309
310 i = 0;
311 skb_queue_walk_safe(&h5->unack, skb, tmp) {
312 if (i++ >= to_remove)
313 break;
314
315 __skb_unlink(skb, &h5->unack);
316 dev_kfree_skb_irq(skb);
317 }
318
319 if (skb_queue_empty(&h5->unack))
320 del_timer(&h5->timer);
321
322unlock:
323 spin_unlock_irqrestore(&h5->unack.lock, flags);
324}
325
326static void h5_handle_internal_rx(struct hci_uart *hu)
327{
328 struct h5 *h5 = hu->priv;
329 const unsigned char sync_req[] = { 0x01, 0x7e };
330 const unsigned char sync_rsp[] = { 0x02, 0x7d };
331 unsigned char conf_req[3] = { 0x03, 0xfc };
332 const unsigned char conf_rsp[] = { 0x04, 0x7b };
333 const unsigned char wakeup_req[] = { 0x05, 0xfa };
334 const unsigned char woken_req[] = { 0x06, 0xf9 };
335 const unsigned char sleep_req[] = { 0x07, 0x78 };
336 const unsigned char *hdr = h5->rx_skb->data;
337 const unsigned char *data = &h5->rx_skb->data[4];
338
339 BT_DBG("%s", hu->hdev->name);
340
341 if (H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT)
342 return;
343
344 if (H5_HDR_LEN(hdr) < 2)
345 return;
346
347 conf_req[2] = h5_cfg_field(h5);
348
349 if (memcmp(data, sync_req, 2) == 0) {
350 if (h5->state == H5_ACTIVE)
351 h5_peer_reset(hu);
352 h5_link_control(hu, sync_rsp, 2);
353 } else if (memcmp(data, sync_rsp, 2) == 0) {
354 if (h5->state == H5_ACTIVE)
355 h5_peer_reset(hu);
356 h5->state = H5_INITIALIZED;
357 h5_link_control(hu, conf_req, 3);
358 } else if (memcmp(data, conf_req, 2) == 0) {
359 h5_link_control(hu, conf_rsp, 2);
360 h5_link_control(hu, conf_req, 3);
361 } else if (memcmp(data, conf_rsp, 2) == 0) {
362 if (H5_HDR_LEN(hdr) > 2)
363 h5->tx_win = (data[2] & 0x07);
364 BT_DBG("Three-wire init complete. tx_win %u", h5->tx_win);
365 h5->state = H5_ACTIVE;
366 hci_uart_init_ready(hu);
367 return;
368 } else if (memcmp(data, sleep_req, 2) == 0) {
369 BT_DBG("Peer went to sleep");
370 h5->sleep = H5_SLEEPING;
371 return;
372 } else if (memcmp(data, woken_req, 2) == 0) {
373 BT_DBG("Peer woke up");
374 h5->sleep = H5_AWAKE;
375 } else if (memcmp(data, wakeup_req, 2) == 0) {
376 BT_DBG("Peer requested wakeup");
377 h5_link_control(hu, woken_req, 2);
378 h5->sleep = H5_AWAKE;
379 } else {
380 BT_DBG("Link Control: 0x%02hhx 0x%02hhx", data[0], data[1]);
381 return;
382 }
383
384 hci_uart_tx_wakeup(hu);
385}
386
387static void h5_complete_rx_pkt(struct hci_uart *hu)
388{
389 struct h5 *h5 = hu->priv;
390 const unsigned char *hdr = h5->rx_skb->data;
391
392 if (H5_HDR_RELIABLE(hdr)) {
393 h5->tx_ack = (h5->tx_ack + 1) % 8;
394 set_bit(H5_TX_ACK_REQ, &h5->flags);
395 hci_uart_tx_wakeup(hu);
396 }
397
398 h5->rx_ack = H5_HDR_ACK(hdr);
399
400 h5_pkt_cull(h5);
401
402 switch (H5_HDR_PKT_TYPE(hdr)) {
403 case HCI_EVENT_PKT:
404 case HCI_ACLDATA_PKT:
405 case HCI_SCODATA_PKT:
406 case HCI_ISODATA_PKT:
407 hci_skb_pkt_type(h5->rx_skb) = H5_HDR_PKT_TYPE(hdr);
408
409 /* Remove Three-wire header */
410 skb_pull(h5->rx_skb, 4);
411
412 hci_recv_frame(hu->hdev, h5->rx_skb);
413 h5->rx_skb = NULL;
414
415 break;
416
417 default:
418 h5_handle_internal_rx(hu);
419 break;
420 }
421
422 h5_reset_rx(h5);
423}
424
425static int h5_rx_crc(struct hci_uart *hu, unsigned char c)
426{
427 h5_complete_rx_pkt(hu);
428
429 return 0;
430}
431
432static int h5_rx_payload(struct hci_uart *hu, unsigned char c)
433{
434 struct h5 *h5 = hu->priv;
435 const unsigned char *hdr = h5->rx_skb->data;
436
437 if (H5_HDR_CRC(hdr)) {
438 h5->rx_func = h5_rx_crc;
439 h5->rx_pending = 2;
440 } else {
441 h5_complete_rx_pkt(hu);
442 }
443
444 return 0;
445}
446
447static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c)
448{
449 struct h5 *h5 = hu->priv;
450 const unsigned char *hdr = h5->rx_skb->data;
451
452 BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u",
453 hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
454 H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
455 H5_HDR_LEN(hdr));
456
457 if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) {
458 bt_dev_err(hu->hdev, "Invalid header checksum");
459 h5_reset_rx(h5);
460 return 0;
461 }
462
463 if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) {
464 bt_dev_err(hu->hdev, "Out-of-order packet arrived (%u != %u)",
465 H5_HDR_SEQ(hdr), h5->tx_ack);
466 h5_reset_rx(h5);
467 return 0;
468 }
469
470 if (h5->state != H5_ACTIVE &&
471 H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) {
472 bt_dev_err(hu->hdev, "Non-link packet received in non-active state");
473 h5_reset_rx(h5);
474 return 0;
475 }
476
477 h5->rx_func = h5_rx_payload;
478 h5->rx_pending = H5_HDR_LEN(hdr);
479
480 return 0;
481}
482
483static int h5_rx_pkt_start(struct hci_uart *hu, unsigned char c)
484{
485 struct h5 *h5 = hu->priv;
486
487 if (c == SLIP_DELIMITER)
488 return 1;
489
490 h5->rx_func = h5_rx_3wire_hdr;
491 h5->rx_pending = 4;
492
493 h5->rx_skb = bt_skb_alloc(H5_MAX_LEN, GFP_ATOMIC);
494 if (!h5->rx_skb) {
495 bt_dev_err(hu->hdev, "Can't allocate mem for new packet");
496 h5_reset_rx(h5);
497 return -ENOMEM;
498 }
499
500 h5->rx_skb->dev = (void *)hu->hdev;
501
502 return 0;
503}
504
505static int h5_rx_delimiter(struct hci_uart *hu, unsigned char c)
506{
507 struct h5 *h5 = hu->priv;
508
509 if (c == SLIP_DELIMITER)
510 h5->rx_func = h5_rx_pkt_start;
511
512 return 1;
513}
514
515static void h5_unslip_one_byte(struct h5 *h5, unsigned char c)
516{
517 const u8 delim = SLIP_DELIMITER, esc = SLIP_ESC;
518 const u8 *byte = &c;
519
520 if (!test_bit(H5_RX_ESC, &h5->flags) && c == SLIP_ESC) {
521 set_bit(H5_RX_ESC, &h5->flags);
522 return;
523 }
524
525 if (test_and_clear_bit(H5_RX_ESC, &h5->flags)) {
526 switch (c) {
527 case SLIP_ESC_DELIM:
528 byte = &delim;
529 break;
530 case SLIP_ESC_ESC:
531 byte = &esc;
532 break;
533 default:
534 BT_ERR("Invalid esc byte 0x%02hhx", c);
535 h5_reset_rx(h5);
536 return;
537 }
538 }
539
540 skb_put_data(h5->rx_skb, byte, 1);
541 h5->rx_pending--;
542
543 BT_DBG("unslipped 0x%02hhx, rx_pending %zu", *byte, h5->rx_pending);
544}
545
546static void h5_reset_rx(struct h5 *h5)
547{
548 if (h5->rx_skb) {
549 kfree_skb(h5->rx_skb);
550 h5->rx_skb = NULL;
551 }
552
553 h5->rx_func = h5_rx_delimiter;
554 h5->rx_pending = 0;
555 clear_bit(H5_RX_ESC, &h5->flags);
556}
557
558static int h5_recv(struct hci_uart *hu, const void *data, int count)
559{
560 struct h5 *h5 = hu->priv;
561 const unsigned char *ptr = data;
562
563 BT_DBG("%s pending %zu count %d", hu->hdev->name, h5->rx_pending,
564 count);
565
566 while (count > 0) {
567 int processed;
568
569 if (h5->rx_pending > 0) {
570 if (*ptr == SLIP_DELIMITER) {
571 bt_dev_err(hu->hdev, "Too short H5 packet");
572 h5_reset_rx(h5);
573 continue;
574 }
575
576 h5_unslip_one_byte(h5, *ptr);
577
578 ptr++; count--;
579 continue;
580 }
581
582 processed = h5->rx_func(hu, *ptr);
583 if (processed < 0)
584 return processed;
585
586 ptr += processed;
587 count -= processed;
588 }
589
590 if (hu->serdev) {
591 pm_runtime_get(&hu->serdev->dev);
592 pm_runtime_mark_last_busy(&hu->serdev->dev);
593 pm_runtime_put_autosuspend(&hu->serdev->dev);
594 }
595
596 return 0;
597}
598
599static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb)
600{
601 struct h5 *h5 = hu->priv;
602
603 if (skb->len > 0xfff) {
604 bt_dev_err(hu->hdev, "Packet too long (%u bytes)", skb->len);
605 kfree_skb(skb);
606 return 0;
607 }
608
609 if (h5->state != H5_ACTIVE) {
610 bt_dev_err(hu->hdev, "Ignoring HCI data in non-active state");
611 kfree_skb(skb);
612 return 0;
613 }
614
615 switch (hci_skb_pkt_type(skb)) {
616 case HCI_ACLDATA_PKT:
617 case HCI_COMMAND_PKT:
618 skb_queue_tail(&h5->rel, skb);
619 break;
620
621 case HCI_SCODATA_PKT:
622 case HCI_ISODATA_PKT:
623 skb_queue_tail(&h5->unrel, skb);
624 break;
625
626 default:
627 bt_dev_err(hu->hdev, "Unknown packet type %u", hci_skb_pkt_type(skb));
628 kfree_skb(skb);
629 break;
630 }
631
632 if (hu->serdev) {
633 pm_runtime_get_sync(&hu->serdev->dev);
634 pm_runtime_mark_last_busy(&hu->serdev->dev);
635 pm_runtime_put_autosuspend(&hu->serdev->dev);
636 }
637
638 return 0;
639}
640
641static void h5_slip_delim(struct sk_buff *skb)
642{
643 const char delim = SLIP_DELIMITER;
644
645 skb_put_data(skb, &delim, 1);
646}
647
648static void h5_slip_one_byte(struct sk_buff *skb, u8 c)
649{
650 const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM };
651 const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC };
652
653 switch (c) {
654 case SLIP_DELIMITER:
655 skb_put_data(skb, &esc_delim, 2);
656 break;
657 case SLIP_ESC:
658 skb_put_data(skb, &esc_esc, 2);
659 break;
660 default:
661 skb_put_data(skb, &c, 1);
662 }
663}
664
665static bool valid_packet_type(u8 type)
666{
667 switch (type) {
668 case HCI_ACLDATA_PKT:
669 case HCI_COMMAND_PKT:
670 case HCI_SCODATA_PKT:
671 case HCI_ISODATA_PKT:
672 case HCI_3WIRE_LINK_PKT:
673 case HCI_3WIRE_ACK_PKT:
674 return true;
675 default:
676 return false;
677 }
678}
679
680static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type,
681 const u8 *data, size_t len)
682{
683 struct h5 *h5 = hu->priv;
684 struct sk_buff *nskb;
685 u8 hdr[4];
686 int i;
687
688 if (!valid_packet_type(pkt_type)) {
689 bt_dev_err(hu->hdev, "Unknown packet type %u", pkt_type);
690 return NULL;
691 }
692
693 /*
694 * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2
695 * (because bytes 0xc0 and 0xdb are escaped, worst case is when
696 * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0
697 * delimiters at start and end).
698 */
699 nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);
700 if (!nskb)
701 return NULL;
702
703 hci_skb_pkt_type(nskb) = pkt_type;
704
705 h5_slip_delim(nskb);
706
707 hdr[0] = h5->tx_ack << 3;
708 clear_bit(H5_TX_ACK_REQ, &h5->flags);
709
710 /* Reliable packet? */
711 if (pkt_type == HCI_ACLDATA_PKT || pkt_type == HCI_COMMAND_PKT) {
712 hdr[0] |= 1 << 7;
713 hdr[0] |= h5->tx_seq;
714 h5->tx_seq = (h5->tx_seq + 1) % 8;
715 }
716
717 hdr[1] = pkt_type | ((len & 0x0f) << 4);
718 hdr[2] = len >> 4;
719 hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff);
720
721 BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u",
722 hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
723 H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
724 H5_HDR_LEN(hdr));
725
726 for (i = 0; i < 4; i++)
727 h5_slip_one_byte(nskb, hdr[i]);
728
729 for (i = 0; i < len; i++)
730 h5_slip_one_byte(nskb, data[i]);
731
732 h5_slip_delim(nskb);
733
734 return nskb;
735}
736
737static struct sk_buff *h5_dequeue(struct hci_uart *hu)
738{
739 struct h5 *h5 = hu->priv;
740 unsigned long flags;
741 struct sk_buff *skb, *nskb;
742
743 if (h5->sleep != H5_AWAKE) {
744 const unsigned char wakeup_req[] = { 0x05, 0xfa };
745
746 if (h5->sleep == H5_WAKING_UP)
747 return NULL;
748
749 h5->sleep = H5_WAKING_UP;
750 BT_DBG("Sending wakeup request");
751
752 mod_timer(&h5->timer, jiffies + HZ / 100);
753 return h5_prepare_pkt(hu, HCI_3WIRE_LINK_PKT, wakeup_req, 2);
754 }
755
756 skb = skb_dequeue(&h5->unrel);
757 if (skb) {
758 nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
759 skb->data, skb->len);
760 if (nskb) {
761 kfree_skb(skb);
762 return nskb;
763 }
764
765 skb_queue_head(&h5->unrel, skb);
766 bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed");
767 }
768
769 spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);
770
771 if (h5->unack.qlen >= h5->tx_win)
772 goto unlock;
773
774 skb = skb_dequeue(&h5->rel);
775 if (skb) {
776 nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
777 skb->data, skb->len);
778 if (nskb) {
779 __skb_queue_tail(&h5->unack, skb);
780 mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT);
781 spin_unlock_irqrestore(&h5->unack.lock, flags);
782 return nskb;
783 }
784
785 skb_queue_head(&h5->rel, skb);
786 bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed");
787 }
788
789unlock:
790 spin_unlock_irqrestore(&h5->unack.lock, flags);
791
792 if (test_bit(H5_TX_ACK_REQ, &h5->flags))
793 return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0);
794
795 return NULL;
796}
797
798static int h5_flush(struct hci_uart *hu)
799{
800 BT_DBG("hu %p", hu);
801 return 0;
802}
803
804static const struct hci_uart_proto h5p = {
805 .id = HCI_UART_3WIRE,
806 .name = "Three-wire (H5)",
807 .open = h5_open,
808 .close = h5_close,
809 .setup = h5_setup,
810 .recv = h5_recv,
811 .enqueue = h5_enqueue,
812 .dequeue = h5_dequeue,
813 .flush = h5_flush,
814};
815
816static int h5_serdev_probe(struct serdev_device *serdev)
817{
818 struct device *dev = &serdev->dev;
819 struct h5 *h5;
820 const struct h5_device_data *data;
821
822 h5 = devm_kzalloc(dev, sizeof(*h5), GFP_KERNEL);
823 if (!h5)
824 return -ENOMEM;
825
826 h5->hu = &h5->serdev_hu;
827 h5->serdev_hu.serdev = serdev;
828 serdev_device_set_drvdata(serdev, h5);
829
830 if (has_acpi_companion(dev)) {
831 const struct acpi_device_id *match;
832
833 match = acpi_match_device(dev->driver->acpi_match_table, dev);
834 if (!match)
835 return -ENODEV;
836
837 data = (const struct h5_device_data *)match->driver_data;
838 h5->vnd = data->vnd;
839 h5->id = (char *)match->id;
840
841 if (h5->vnd->acpi_gpio_map)
842 devm_acpi_dev_add_driver_gpios(dev,
843 h5->vnd->acpi_gpio_map);
844 } else {
845 data = of_device_get_match_data(dev);
846 if (!data)
847 return -ENODEV;
848
849 h5->vnd = data->vnd;
850 }
851
852 if (data->driver_info & H5_INFO_WAKEUP_DISABLE)
853 set_bit(H5_WAKEUP_DISABLE, &h5->flags);
854
855 h5->enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);
856 if (IS_ERR(h5->enable_gpio))
857 return PTR_ERR(h5->enable_gpio);
858
859 h5->device_wake_gpio = devm_gpiod_get_optional(dev, "device-wake",
860 GPIOD_OUT_LOW);
861 if (IS_ERR(h5->device_wake_gpio))
862 return PTR_ERR(h5->device_wake_gpio);
863
864 return hci_uart_register_device(&h5->serdev_hu, &h5p);
865}
866
867static void h5_serdev_remove(struct serdev_device *serdev)
868{
869 struct h5 *h5 = serdev_device_get_drvdata(serdev);
870
871 hci_uart_unregister_device(&h5->serdev_hu);
872}
873
874static int __maybe_unused h5_serdev_suspend(struct device *dev)
875{
876 struct h5 *h5 = dev_get_drvdata(dev);
877 int ret = 0;
878
879 if (h5->vnd && h5->vnd->suspend)
880 ret = h5->vnd->suspend(h5);
881
882 return ret;
883}
884
885static int __maybe_unused h5_serdev_resume(struct device *dev)
886{
887 struct h5 *h5 = dev_get_drvdata(dev);
888 int ret = 0;
889
890 if (h5->vnd && h5->vnd->resume)
891 ret = h5->vnd->resume(h5);
892
893 return ret;
894}
895
896#ifdef CONFIG_BT_HCIUART_RTL
897static int h5_btrtl_setup(struct h5 *h5)
898{
899 struct btrtl_device_info *btrtl_dev;
900 struct sk_buff *skb;
901 __le32 baudrate_data;
902 u32 device_baudrate;
903 unsigned int controller_baudrate;
904 bool flow_control;
905 int err;
906
907 btrtl_dev = btrtl_initialize(h5->hu->hdev, h5->id);
908 if (IS_ERR(btrtl_dev))
909 return PTR_ERR(btrtl_dev);
910
911 err = btrtl_get_uart_settings(h5->hu->hdev, btrtl_dev,
912 &controller_baudrate, &device_baudrate,
913 &flow_control);
914 if (err)
915 goto out_free;
916
917 baudrate_data = cpu_to_le32(device_baudrate);
918 skb = __hci_cmd_sync(h5->hu->hdev, 0xfc17, sizeof(baudrate_data),
919 &baudrate_data, HCI_INIT_TIMEOUT);
920 if (IS_ERR(skb)) {
921 rtl_dev_err(h5->hu->hdev, "set baud rate command failed\n");
922 err = PTR_ERR(skb);
923 goto out_free;
924 } else {
925 kfree_skb(skb);
926 }
927 /* Give the device some time to set up the new baudrate. */
928 usleep_range(10000, 20000);
929
930 serdev_device_set_baudrate(h5->hu->serdev, controller_baudrate);
931 serdev_device_set_flow_control(h5->hu->serdev, flow_control);
932
933 if (flow_control)
934 set_bit(H5_HW_FLOW_CONTROL, &h5->flags);
935
936 err = btrtl_download_firmware(h5->hu->hdev, btrtl_dev);
937 /* Give the device some time before the hci-core sends it a reset */
938 usleep_range(10000, 20000);
939
940 btrtl_set_quirks(h5->hu->hdev, btrtl_dev);
941
942out_free:
943 btrtl_free(btrtl_dev);
944
945 return err;
946}
947
948static void h5_btrtl_open(struct h5 *h5)
949{
950 /*
951 * Since h5_btrtl_resume() does a device_reprobe() the suspend handling
952 * done by the hci_suspend_notifier is not necessary; it actually causes
953 * delays and a bunch of errors to get logged, so disable it.
954 */
955 if (test_bit(H5_WAKEUP_DISABLE, &h5->flags))
956 set_bit(HCI_UART_NO_SUSPEND_NOTIFIER, &h5->hu->flags);
957
958 /* Devices always start with these fixed parameters */
959 serdev_device_set_flow_control(h5->hu->serdev, false);
960 serdev_device_set_parity(h5->hu->serdev, SERDEV_PARITY_EVEN);
961 serdev_device_set_baudrate(h5->hu->serdev, 115200);
962
963 if (!test_bit(H5_WAKEUP_DISABLE, &h5->flags)) {
964 pm_runtime_set_active(&h5->hu->serdev->dev);
965 pm_runtime_use_autosuspend(&h5->hu->serdev->dev);
966 pm_runtime_set_autosuspend_delay(&h5->hu->serdev->dev,
967 SUSPEND_TIMEOUT_MS);
968 pm_runtime_enable(&h5->hu->serdev->dev);
969 }
970
971 /* The controller needs reset to startup */
972 gpiod_set_value_cansleep(h5->enable_gpio, 0);
973 gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
974 msleep(100);
975
976 /* The controller needs up to 500ms to wakeup */
977 gpiod_set_value_cansleep(h5->enable_gpio, 1);
978 gpiod_set_value_cansleep(h5->device_wake_gpio, 1);
979 msleep(500);
980}
981
982static void h5_btrtl_close(struct h5 *h5)
983{
984 if (!test_bit(H5_WAKEUP_DISABLE, &h5->flags))
985 pm_runtime_disable(&h5->hu->serdev->dev);
986
987 gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
988 gpiod_set_value_cansleep(h5->enable_gpio, 0);
989}
990
991/* Suspend/resume support. On many devices the RTL BT device loses power during
992 * suspend/resume, causing it to lose its firmware and all state. So we simply
993 * turn it off on suspend and reprobe on resume. This mirrors how RTL devices
994 * are handled in the USB driver, where the BTUSB_WAKEUP_DISABLE is used which
995 * also causes a reprobe on resume.
996 */
997static int h5_btrtl_suspend(struct h5 *h5)
998{
999 serdev_device_set_flow_control(h5->hu->serdev, false);
1000 gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
1001
1002 if (test_bit(H5_WAKEUP_DISABLE, &h5->flags))
1003 gpiod_set_value_cansleep(h5->enable_gpio, 0);
1004
1005 return 0;
1006}
1007
1008struct h5_btrtl_reprobe {
1009 struct device *dev;
1010 struct work_struct work;
1011};
1012
1013static void h5_btrtl_reprobe_worker(struct work_struct *work)
1014{
1015 struct h5_btrtl_reprobe *reprobe =
1016 container_of(work, struct h5_btrtl_reprobe, work);
1017 int ret;
1018
1019 ret = device_reprobe(reprobe->dev);
1020 if (ret && ret != -EPROBE_DEFER)
1021 dev_err(reprobe->dev, "Reprobe error %d\n", ret);
1022
1023 put_device(reprobe->dev);
1024 kfree(reprobe);
1025 module_put(THIS_MODULE);
1026}
1027
1028static int h5_btrtl_resume(struct h5 *h5)
1029{
1030 if (test_bit(H5_WAKEUP_DISABLE, &h5->flags)) {
1031 struct h5_btrtl_reprobe *reprobe;
1032
1033 reprobe = kzalloc(sizeof(*reprobe), GFP_KERNEL);
1034 if (!reprobe)
1035 return -ENOMEM;
1036
1037 __module_get(THIS_MODULE);
1038
1039 INIT_WORK(&reprobe->work, h5_btrtl_reprobe_worker);
1040 reprobe->dev = get_device(&h5->hu->serdev->dev);
1041 queue_work(system_long_wq, &reprobe->work);
1042 } else {
1043 gpiod_set_value_cansleep(h5->device_wake_gpio, 1);
1044
1045 if (test_bit(H5_HW_FLOW_CONTROL, &h5->flags))
1046 serdev_device_set_flow_control(h5->hu->serdev, true);
1047 }
1048
1049 return 0;
1050}
1051
1052static const struct acpi_gpio_params btrtl_device_wake_gpios = { 0, 0, false };
1053static const struct acpi_gpio_params btrtl_enable_gpios = { 1, 0, false };
1054static const struct acpi_gpio_params btrtl_host_wake_gpios = { 2, 0, false };
1055static const struct acpi_gpio_mapping acpi_btrtl_gpios[] = {
1056 { "device-wake-gpios", &btrtl_device_wake_gpios, 1 },
1057 { "enable-gpios", &btrtl_enable_gpios, 1 },
1058 { "host-wake-gpios", &btrtl_host_wake_gpios, 1 },
1059 {},
1060};
1061
1062static struct h5_vnd rtl_vnd = {
1063 .setup = h5_btrtl_setup,
1064 .open = h5_btrtl_open,
1065 .close = h5_btrtl_close,
1066 .suspend = h5_btrtl_suspend,
1067 .resume = h5_btrtl_resume,
1068 .acpi_gpio_map = acpi_btrtl_gpios,
1069};
1070
1071static const struct h5_device_data h5_data_rtl8822cs = {
1072 .vnd = &rtl_vnd,
1073};
1074
1075static const struct h5_device_data h5_data_rtl8723bs = {
1076 .driver_info = H5_INFO_WAKEUP_DISABLE,
1077 .vnd = &rtl_vnd,
1078};
1079#endif
1080
1081#ifdef CONFIG_ACPI
1082static const struct acpi_device_id h5_acpi_match[] = {
1083#ifdef CONFIG_BT_HCIUART_RTL
1084 { "OBDA0623", (kernel_ulong_t)&h5_data_rtl8723bs },
1085 { "OBDA8723", (kernel_ulong_t)&h5_data_rtl8723bs },
1086#endif
1087 { },
1088};
1089MODULE_DEVICE_TABLE(acpi, h5_acpi_match);
1090#endif
1091
1092static const struct dev_pm_ops h5_serdev_pm_ops = {
1093 SET_SYSTEM_SLEEP_PM_OPS(h5_serdev_suspend, h5_serdev_resume)
1094 SET_RUNTIME_PM_OPS(h5_serdev_suspend, h5_serdev_resume, NULL)
1095};
1096
1097static const struct of_device_id rtl_bluetooth_of_match[] = {
1098#ifdef CONFIG_BT_HCIUART_RTL
1099 { .compatible = "realtek,rtl8822cs-bt",
1100 .data = (const void *)&h5_data_rtl8822cs },
1101 { .compatible = "realtek,rtl8723bs-bt",
1102 .data = (const void *)&h5_data_rtl8723bs },
1103 { .compatible = "realtek,rtl8723ds-bt",
1104 .data = (const void *)&h5_data_rtl8723bs },
1105#endif
1106 { },
1107};
1108MODULE_DEVICE_TABLE(of, rtl_bluetooth_of_match);
1109
1110static struct serdev_device_driver h5_serdev_driver = {
1111 .probe = h5_serdev_probe,
1112 .remove = h5_serdev_remove,
1113 .driver = {
1114 .name = "hci_uart_h5",
1115 .acpi_match_table = ACPI_PTR(h5_acpi_match),
1116 .pm = &h5_serdev_pm_ops,
1117 .of_match_table = rtl_bluetooth_of_match,
1118 },
1119};
1120
1121int __init h5_init(void)
1122{
1123 serdev_device_driver_register(&h5_serdev_driver);
1124 return hci_uart_register_proto(&h5p);
1125}
1126
1127int __exit h5_deinit(void)
1128{
1129 serdev_device_driver_unregister(&h5_serdev_driver);
1130 return hci_uart_unregister_proto(&h5p);
1131}