1 /*
2 *
3 * Bluetooth HCI Three-wire UART driver
4 *
5 * Copyright (C) 2012 Intel Corporation
6 *
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 *
22 */
23
24 #include <linux/acpi.h>
25 #include <linux/errno.h>
26 #include <linux/gpio/consumer.h>
27 #include <linux/kernel.h>
28 #include <linux/mod_devicetable.h>
29 #include <linux/serdev.h>
30 #include <linux/skbuff.h>
31
32 #include <net/bluetooth/bluetooth.h>
33 #include <net/bluetooth/hci_core.h>
34
35 #include "btrtl.h"
36 #include "hci_uart.h"
37
38 #define HCI_3WIRE_ACK_PKT 0
39 #define HCI_3WIRE_LINK_PKT 15
40
41 /* Sliding window size */
42 #define H5_TX_WIN_MAX 4
43
44 #define H5_ACK_TIMEOUT msecs_to_jiffies(250)
45 #define H5_SYNC_TIMEOUT msecs_to_jiffies(100)
46
47 /*
48 * Maximum Three-wire packet:
49 * 4 byte header + max value for 12-bit length + 2 bytes for CRC
50 */
51 #define H5_MAX_LEN (4 + 0xfff + 2)
52
53 /* Convenience macros for reading Three-wire header values */
54 #define H5_HDR_SEQ(hdr) ((hdr)[0] & 0x07)
55 #define H5_HDR_ACK(hdr) (((hdr)[0] >> 3) & 0x07)
56 #define H5_HDR_CRC(hdr) (((hdr)[0] >> 6) & 0x01)
57 #define H5_HDR_RELIABLE(hdr) (((hdr)[0] >> 7) & 0x01)
58 #define H5_HDR_PKT_TYPE(hdr) ((hdr)[1] & 0x0f)
59 #define H5_HDR_LEN(hdr) ((((hdr)[1] >> 4) & 0x0f) + ((hdr)[2] << 4))
60
61 #define SLIP_DELIMITER 0xc0
62 #define SLIP_ESC 0xdb
63 #define SLIP_ESC_DELIM 0xdc
64 #define SLIP_ESC_ESC 0xdd
65
66 /* H5 state flags */
67 enum {
68 H5_RX_ESC, /* SLIP escape mode */
69 H5_TX_ACK_REQ, /* Pending ack to send */
70 };
71
72 struct h5 {
73 /* Must be the first member, hci_serdev.c expects this. */
74 struct hci_uart serdev_hu;
75
76 struct sk_buff_head unack; /* Unack'ed packets queue */
77 struct sk_buff_head rel; /* Reliable packets queue */
78 struct sk_buff_head unrel; /* Unreliable packets queue */
79
80 unsigned long flags;
81
82 struct sk_buff *rx_skb; /* Receive buffer */
83 size_t rx_pending; /* Expecting more bytes */
84 u8 rx_ack; /* Last ack number received */
85
86 int (*rx_func)(struct hci_uart *hu, u8 c);
87
88 struct timer_list timer; /* Retransmission timer */
89 struct hci_uart *hu; /* Parent HCI UART */
90
91 u8 tx_seq; /* Next seq number to send */
92 u8 tx_ack; /* Next ack number to send */
93 u8 tx_win; /* Sliding window size */
94
95 enum {
96 H5_UNINITIALIZED,
97 H5_INITIALIZED,
98 H5_ACTIVE,
99 } state;
100
101 enum {
102 H5_AWAKE,
103 H5_SLEEPING,
104 H5_WAKING_UP,
105 } sleep;
106
107 const struct h5_vnd *vnd;
108 const char *id;
109
110 struct gpio_desc *enable_gpio;
111 struct gpio_desc *device_wake_gpio;
112 };
113
114 struct h5_vnd {
115 int (*setup)(struct h5 *h5);
116 void (*open)(struct h5 *h5);
117 void (*close)(struct h5 *h5);
118 const struct acpi_gpio_mapping *acpi_gpio_map;
119 };
120
121 static void h5_reset_rx(struct h5 *h5);
122
h5_link_control(struct hci_uart * hu,const void * data,size_t len)123 static void h5_link_control(struct hci_uart *hu, const void *data, size_t len)
124 {
125 struct h5 *h5 = hu->priv;
126 struct sk_buff *nskb;
127
128 nskb = alloc_skb(3, GFP_ATOMIC);
129 if (!nskb)
130 return;
131
132 hci_skb_pkt_type(nskb) = HCI_3WIRE_LINK_PKT;
133
134 skb_put_data(nskb, data, len);
135
136 skb_queue_tail(&h5->unrel, nskb);
137 }
138
h5_cfg_field(struct h5 * h5)139 static u8 h5_cfg_field(struct h5 *h5)
140 {
141 /* Sliding window size (first 3 bits) */
142 return h5->tx_win & 0x07;
143 }
144
h5_timed_event(struct timer_list * t)145 static void h5_timed_event(struct timer_list *t)
146 {
147 const unsigned char sync_req[] = { 0x01, 0x7e };
148 unsigned char conf_req[3] = { 0x03, 0xfc };
149 struct h5 *h5 = from_timer(h5, t, timer);
150 struct hci_uart *hu = h5->hu;
151 struct sk_buff *skb;
152 unsigned long flags;
153
154 BT_DBG("%s", hu->hdev->name);
155
156 if (h5->state == H5_UNINITIALIZED)
157 h5_link_control(hu, sync_req, sizeof(sync_req));
158
159 if (h5->state == H5_INITIALIZED) {
160 conf_req[2] = h5_cfg_field(h5);
161 h5_link_control(hu, conf_req, sizeof(conf_req));
162 }
163
164 if (h5->state != H5_ACTIVE) {
165 mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT);
166 goto wakeup;
167 }
168
169 if (h5->sleep != H5_AWAKE) {
170 h5->sleep = H5_SLEEPING;
171 goto wakeup;
172 }
173
174 BT_DBG("hu %p retransmitting %u pkts", hu, h5->unack.qlen);
175
176 spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);
177
178 while ((skb = __skb_dequeue_tail(&h5->unack)) != NULL) {
179 h5->tx_seq = (h5->tx_seq - 1) & 0x07;
180 skb_queue_head(&h5->rel, skb);
181 }
182
183 spin_unlock_irqrestore(&h5->unack.lock, flags);
184
185 wakeup:
186 hci_uart_tx_wakeup(hu);
187 }
188
h5_peer_reset(struct hci_uart * hu)189 static void h5_peer_reset(struct hci_uart *hu)
190 {
191 struct h5 *h5 = hu->priv;
192
193 BT_ERR("Peer device has reset");
194
195 h5->state = H5_UNINITIALIZED;
196
197 del_timer(&h5->timer);
198
199 skb_queue_purge(&h5->rel);
200 skb_queue_purge(&h5->unrel);
201 skb_queue_purge(&h5->unack);
202
203 h5->tx_seq = 0;
204 h5->tx_ack = 0;
205
206 /* Send reset request to upper stack */
207 hci_reset_dev(hu->hdev);
208 }
209
h5_open(struct hci_uart * hu)210 static int h5_open(struct hci_uart *hu)
211 {
212 struct h5 *h5;
213 const unsigned char sync[] = { 0x01, 0x7e };
214
215 BT_DBG("hu %p", hu);
216
217 if (hu->serdev) {
218 h5 = serdev_device_get_drvdata(hu->serdev);
219 } else {
220 h5 = kzalloc(sizeof(*h5), GFP_KERNEL);
221 if (!h5)
222 return -ENOMEM;
223 }
224
225 hu->priv = h5;
226 h5->hu = hu;
227
228 skb_queue_head_init(&h5->unack);
229 skb_queue_head_init(&h5->rel);
230 skb_queue_head_init(&h5->unrel);
231
232 h5_reset_rx(h5);
233
234 timer_setup(&h5->timer, h5_timed_event, 0);
235
236 h5->tx_win = H5_TX_WIN_MAX;
237
238 if (h5->vnd && h5->vnd->open)
239 h5->vnd->open(h5);
240
241 set_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags);
242
243 /* Send initial sync request */
244 h5_link_control(hu, sync, sizeof(sync));
245 mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT);
246
247 return 0;
248 }
249
h5_close(struct hci_uart * hu)250 static int h5_close(struct hci_uart *hu)
251 {
252 struct h5 *h5 = hu->priv;
253
254 del_timer_sync(&h5->timer);
255
256 skb_queue_purge(&h5->unack);
257 skb_queue_purge(&h5->rel);
258 skb_queue_purge(&h5->unrel);
259
260 kfree_skb(h5->rx_skb);
261 h5->rx_skb = NULL;
262
263 if (h5->vnd && h5->vnd->close)
264 h5->vnd->close(h5);
265
266 if (!hu->serdev)
267 kfree(h5);
268
269 return 0;
270 }
271
h5_setup(struct hci_uart * hu)272 static int h5_setup(struct hci_uart *hu)
273 {
274 struct h5 *h5 = hu->priv;
275
276 if (h5->vnd && h5->vnd->setup)
277 return h5->vnd->setup(h5);
278
279 return 0;
280 }
281
h5_pkt_cull(struct h5 * h5)282 static void h5_pkt_cull(struct h5 *h5)
283 {
284 struct sk_buff *skb, *tmp;
285 unsigned long flags;
286 int i, to_remove;
287 u8 seq;
288
289 spin_lock_irqsave(&h5->unack.lock, flags);
290
291 to_remove = skb_queue_len(&h5->unack);
292 if (to_remove == 0)
293 goto unlock;
294
295 seq = h5->tx_seq;
296
297 while (to_remove > 0) {
298 if (h5->rx_ack == seq)
299 break;
300
301 to_remove--;
302 seq = (seq - 1) & 0x07;
303 }
304
305 if (seq != h5->rx_ack)
306 BT_ERR("Controller acked invalid packet");
307
308 i = 0;
309 skb_queue_walk_safe(&h5->unack, skb, tmp) {
310 if (i++ >= to_remove)
311 break;
312
313 __skb_unlink(skb, &h5->unack);
314 dev_kfree_skb_irq(skb);
315 }
316
317 if (skb_queue_empty(&h5->unack))
318 del_timer(&h5->timer);
319
320 unlock:
321 spin_unlock_irqrestore(&h5->unack.lock, flags);
322 }
323
h5_handle_internal_rx(struct hci_uart * hu)324 static void h5_handle_internal_rx(struct hci_uart *hu)
325 {
326 struct h5 *h5 = hu->priv;
327 const unsigned char sync_req[] = { 0x01, 0x7e };
328 const unsigned char sync_rsp[] = { 0x02, 0x7d };
329 unsigned char conf_req[3] = { 0x03, 0xfc };
330 const unsigned char conf_rsp[] = { 0x04, 0x7b };
331 const unsigned char wakeup_req[] = { 0x05, 0xfa };
332 const unsigned char woken_req[] = { 0x06, 0xf9 };
333 const unsigned char sleep_req[] = { 0x07, 0x78 };
334 const unsigned char *hdr = h5->rx_skb->data;
335 const unsigned char *data = &h5->rx_skb->data[4];
336
337 BT_DBG("%s", hu->hdev->name);
338
339 if (H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT)
340 return;
341
342 if (H5_HDR_LEN(hdr) < 2)
343 return;
344
345 conf_req[2] = h5_cfg_field(h5);
346
347 if (memcmp(data, sync_req, 2) == 0) {
348 if (h5->state == H5_ACTIVE)
349 h5_peer_reset(hu);
350 h5_link_control(hu, sync_rsp, 2);
351 } else if (memcmp(data, sync_rsp, 2) == 0) {
352 if (h5->state == H5_ACTIVE)
353 h5_peer_reset(hu);
354 h5->state = H5_INITIALIZED;
355 h5_link_control(hu, conf_req, 3);
356 } else if (memcmp(data, conf_req, 2) == 0) {
357 h5_link_control(hu, conf_rsp, 2);
358 h5_link_control(hu, conf_req, 3);
359 } else if (memcmp(data, conf_rsp, 2) == 0) {
360 if (H5_HDR_LEN(hdr) > 2)
361 h5->tx_win = (data[2] & 0x07);
362 BT_DBG("Three-wire init complete. tx_win %u", h5->tx_win);
363 h5->state = H5_ACTIVE;
364 hci_uart_init_ready(hu);
365 return;
366 } else if (memcmp(data, sleep_req, 2) == 0) {
367 BT_DBG("Peer went to sleep");
368 h5->sleep = H5_SLEEPING;
369 return;
370 } else if (memcmp(data, woken_req, 2) == 0) {
371 BT_DBG("Peer woke up");
372 h5->sleep = H5_AWAKE;
373 } else if (memcmp(data, wakeup_req, 2) == 0) {
374 BT_DBG("Peer requested wakeup");
375 h5_link_control(hu, woken_req, 2);
376 h5->sleep = H5_AWAKE;
377 } else {
378 BT_DBG("Link Control: 0x%02hhx 0x%02hhx", data[0], data[1]);
379 return;
380 }
381
382 hci_uart_tx_wakeup(hu);
383 }
384
h5_complete_rx_pkt(struct hci_uart * hu)385 static void h5_complete_rx_pkt(struct hci_uart *hu)
386 {
387 struct h5 *h5 = hu->priv;
388 const unsigned char *hdr = h5->rx_skb->data;
389
390 if (H5_HDR_RELIABLE(hdr)) {
391 h5->tx_ack = (h5->tx_ack + 1) % 8;
392 set_bit(H5_TX_ACK_REQ, &h5->flags);
393 hci_uart_tx_wakeup(hu);
394 }
395
396 h5->rx_ack = H5_HDR_ACK(hdr);
397
398 h5_pkt_cull(h5);
399
400 switch (H5_HDR_PKT_TYPE(hdr)) {
401 case HCI_EVENT_PKT:
402 case HCI_ACLDATA_PKT:
403 case HCI_SCODATA_PKT:
404 hci_skb_pkt_type(h5->rx_skb) = H5_HDR_PKT_TYPE(hdr);
405
406 /* Remove Three-wire header */
407 skb_pull(h5->rx_skb, 4);
408
409 hci_recv_frame(hu->hdev, h5->rx_skb);
410 h5->rx_skb = NULL;
411
412 break;
413
414 default:
415 h5_handle_internal_rx(hu);
416 break;
417 }
418
419 h5_reset_rx(h5);
420 }
421
h5_rx_crc(struct hci_uart * hu,unsigned char c)422 static int h5_rx_crc(struct hci_uart *hu, unsigned char c)
423 {
424 h5_complete_rx_pkt(hu);
425
426 return 0;
427 }
428
h5_rx_payload(struct hci_uart * hu,unsigned char c)429 static int h5_rx_payload(struct hci_uart *hu, unsigned char c)
430 {
431 struct h5 *h5 = hu->priv;
432 const unsigned char *hdr = h5->rx_skb->data;
433
434 if (H5_HDR_CRC(hdr)) {
435 h5->rx_func = h5_rx_crc;
436 h5->rx_pending = 2;
437 } else {
438 h5_complete_rx_pkt(hu);
439 }
440
441 return 0;
442 }
443
h5_rx_3wire_hdr(struct hci_uart * hu,unsigned char c)444 static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c)
445 {
446 struct h5 *h5 = hu->priv;
447 const unsigned char *hdr = h5->rx_skb->data;
448
449 BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u",
450 hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
451 H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
452 H5_HDR_LEN(hdr));
453
454 if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) {
455 BT_ERR("Invalid header checksum");
456 h5_reset_rx(h5);
457 return 0;
458 }
459
460 if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) {
461 BT_ERR("Out-of-order packet arrived (%u != %u)",
462 H5_HDR_SEQ(hdr), h5->tx_ack);
463 h5_reset_rx(h5);
464 return 0;
465 }
466
467 if (h5->state != H5_ACTIVE &&
468 H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) {
469 BT_ERR("Non-link packet received in non-active state");
470 h5_reset_rx(h5);
471 return 0;
472 }
473
474 h5->rx_func = h5_rx_payload;
475 h5->rx_pending = H5_HDR_LEN(hdr);
476
477 return 0;
478 }
479
h5_rx_pkt_start(struct hci_uart * hu,unsigned char c)480 static int h5_rx_pkt_start(struct hci_uart *hu, unsigned char c)
481 {
482 struct h5 *h5 = hu->priv;
483
484 if (c == SLIP_DELIMITER)
485 return 1;
486
487 h5->rx_func = h5_rx_3wire_hdr;
488 h5->rx_pending = 4;
489
490 h5->rx_skb = bt_skb_alloc(H5_MAX_LEN, GFP_ATOMIC);
491 if (!h5->rx_skb) {
492 BT_ERR("Can't allocate mem for new packet");
493 h5_reset_rx(h5);
494 return -ENOMEM;
495 }
496
497 h5->rx_skb->dev = (void *)hu->hdev;
498
499 return 0;
500 }
501
h5_rx_delimiter(struct hci_uart * hu,unsigned char c)502 static int h5_rx_delimiter(struct hci_uart *hu, unsigned char c)
503 {
504 struct h5 *h5 = hu->priv;
505
506 if (c == SLIP_DELIMITER)
507 h5->rx_func = h5_rx_pkt_start;
508
509 return 1;
510 }
511
h5_unslip_one_byte(struct h5 * h5,unsigned char c)512 static void h5_unslip_one_byte(struct h5 *h5, unsigned char c)
513 {
514 const u8 delim = SLIP_DELIMITER, esc = SLIP_ESC;
515 const u8 *byte = &c;
516
517 if (!test_bit(H5_RX_ESC, &h5->flags) && c == SLIP_ESC) {
518 set_bit(H5_RX_ESC, &h5->flags);
519 return;
520 }
521
522 if (test_and_clear_bit(H5_RX_ESC, &h5->flags)) {
523 switch (c) {
524 case SLIP_ESC_DELIM:
525 byte = &delim;
526 break;
527 case SLIP_ESC_ESC:
528 byte = &esc;
529 break;
530 default:
531 BT_ERR("Invalid esc byte 0x%02hhx", c);
532 h5_reset_rx(h5);
533 return;
534 }
535 }
536
537 skb_put_data(h5->rx_skb, byte, 1);
538 h5->rx_pending--;
539
540 BT_DBG("unsliped 0x%02hhx, rx_pending %zu", *byte, h5->rx_pending);
541 }
542
h5_reset_rx(struct h5 * h5)543 static void h5_reset_rx(struct h5 *h5)
544 {
545 if (h5->rx_skb) {
546 kfree_skb(h5->rx_skb);
547 h5->rx_skb = NULL;
548 }
549
550 h5->rx_func = h5_rx_delimiter;
551 h5->rx_pending = 0;
552 clear_bit(H5_RX_ESC, &h5->flags);
553 }
554
h5_recv(struct hci_uart * hu,const void * data,int count)555 static int h5_recv(struct hci_uart *hu, const void *data, int count)
556 {
557 struct h5 *h5 = hu->priv;
558 const unsigned char *ptr = data;
559
560 BT_DBG("%s pending %zu count %d", hu->hdev->name, h5->rx_pending,
561 count);
562
563 while (count > 0) {
564 int processed;
565
566 if (h5->rx_pending > 0) {
567 if (*ptr == SLIP_DELIMITER) {
568 BT_ERR("Too short H5 packet");
569 h5_reset_rx(h5);
570 continue;
571 }
572
573 h5_unslip_one_byte(h5, *ptr);
574
575 ptr++; count--;
576 continue;
577 }
578
579 processed = h5->rx_func(hu, *ptr);
580 if (processed < 0)
581 return processed;
582
583 ptr += processed;
584 count -= processed;
585 }
586
587 return 0;
588 }
589
h5_enqueue(struct hci_uart * hu,struct sk_buff * skb)590 static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb)
591 {
592 struct h5 *h5 = hu->priv;
593
594 if (skb->len > 0xfff) {
595 BT_ERR("Packet too long (%u bytes)", skb->len);
596 kfree_skb(skb);
597 return 0;
598 }
599
600 if (h5->state != H5_ACTIVE) {
601 BT_ERR("Ignoring HCI data in non-active state");
602 kfree_skb(skb);
603 return 0;
604 }
605
606 switch (hci_skb_pkt_type(skb)) {
607 case HCI_ACLDATA_PKT:
608 case HCI_COMMAND_PKT:
609 skb_queue_tail(&h5->rel, skb);
610 break;
611
612 case HCI_SCODATA_PKT:
613 skb_queue_tail(&h5->unrel, skb);
614 break;
615
616 default:
617 BT_ERR("Unknown packet type %u", hci_skb_pkt_type(skb));
618 kfree_skb(skb);
619 break;
620 }
621
622 return 0;
623 }
624
h5_slip_delim(struct sk_buff * skb)625 static void h5_slip_delim(struct sk_buff *skb)
626 {
627 const char delim = SLIP_DELIMITER;
628
629 skb_put_data(skb, &delim, 1);
630 }
631
h5_slip_one_byte(struct sk_buff * skb,u8 c)632 static void h5_slip_one_byte(struct sk_buff *skb, u8 c)
633 {
634 const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM };
635 const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC };
636
637 switch (c) {
638 case SLIP_DELIMITER:
639 skb_put_data(skb, &esc_delim, 2);
640 break;
641 case SLIP_ESC:
642 skb_put_data(skb, &esc_esc, 2);
643 break;
644 default:
645 skb_put_data(skb, &c, 1);
646 }
647 }
648
valid_packet_type(u8 type)649 static bool valid_packet_type(u8 type)
650 {
651 switch (type) {
652 case HCI_ACLDATA_PKT:
653 case HCI_COMMAND_PKT:
654 case HCI_SCODATA_PKT:
655 case HCI_3WIRE_LINK_PKT:
656 case HCI_3WIRE_ACK_PKT:
657 return true;
658 default:
659 return false;
660 }
661 }
662
h5_prepare_pkt(struct hci_uart * hu,u8 pkt_type,const u8 * data,size_t len)663 static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type,
664 const u8 *data, size_t len)
665 {
666 struct h5 *h5 = hu->priv;
667 struct sk_buff *nskb;
668 u8 hdr[4];
669 int i;
670
671 if (!valid_packet_type(pkt_type)) {
672 BT_ERR("Unknown packet type %u", pkt_type);
673 return NULL;
674 }
675
676 /*
677 * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2
678 * (because bytes 0xc0 and 0xdb are escaped, worst case is when
679 * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0
680 * delimiters at start and end).
681 */
682 nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);
683 if (!nskb)
684 return NULL;
685
686 hci_skb_pkt_type(nskb) = pkt_type;
687
688 h5_slip_delim(nskb);
689
690 hdr[0] = h5->tx_ack << 3;
691 clear_bit(H5_TX_ACK_REQ, &h5->flags);
692
693 /* Reliable packet? */
694 if (pkt_type == HCI_ACLDATA_PKT || pkt_type == HCI_COMMAND_PKT) {
695 hdr[0] |= 1 << 7;
696 hdr[0] |= h5->tx_seq;
697 h5->tx_seq = (h5->tx_seq + 1) % 8;
698 }
699
700 hdr[1] = pkt_type | ((len & 0x0f) << 4);
701 hdr[2] = len >> 4;
702 hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff);
703
704 BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u",
705 hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
706 H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
707 H5_HDR_LEN(hdr));
708
709 for (i = 0; i < 4; i++)
710 h5_slip_one_byte(nskb, hdr[i]);
711
712 for (i = 0; i < len; i++)
713 h5_slip_one_byte(nskb, data[i]);
714
715 h5_slip_delim(nskb);
716
717 return nskb;
718 }
719
h5_dequeue(struct hci_uart * hu)720 static struct sk_buff *h5_dequeue(struct hci_uart *hu)
721 {
722 struct h5 *h5 = hu->priv;
723 unsigned long flags;
724 struct sk_buff *skb, *nskb;
725
726 if (h5->sleep != H5_AWAKE) {
727 const unsigned char wakeup_req[] = { 0x05, 0xfa };
728
729 if (h5->sleep == H5_WAKING_UP)
730 return NULL;
731
732 h5->sleep = H5_WAKING_UP;
733 BT_DBG("Sending wakeup request");
734
735 mod_timer(&h5->timer, jiffies + HZ / 100);
736 return h5_prepare_pkt(hu, HCI_3WIRE_LINK_PKT, wakeup_req, 2);
737 }
738
739 skb = skb_dequeue(&h5->unrel);
740 if (skb) {
741 nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
742 skb->data, skb->len);
743 if (nskb) {
744 kfree_skb(skb);
745 return nskb;
746 }
747
748 skb_queue_head(&h5->unrel, skb);
749 BT_ERR("Could not dequeue pkt because alloc_skb failed");
750 }
751
752 spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);
753
754 if (h5->unack.qlen >= h5->tx_win)
755 goto unlock;
756
757 skb = skb_dequeue(&h5->rel);
758 if (skb) {
759 nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
760 skb->data, skb->len);
761 if (nskb) {
762 __skb_queue_tail(&h5->unack, skb);
763 mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT);
764 spin_unlock_irqrestore(&h5->unack.lock, flags);
765 return nskb;
766 }
767
768 skb_queue_head(&h5->rel, skb);
769 BT_ERR("Could not dequeue pkt because alloc_skb failed");
770 }
771
772 unlock:
773 spin_unlock_irqrestore(&h5->unack.lock, flags);
774
775 if (test_bit(H5_TX_ACK_REQ, &h5->flags))
776 return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0);
777
778 return NULL;
779 }
780
h5_flush(struct hci_uart * hu)781 static int h5_flush(struct hci_uart *hu)
782 {
783 BT_DBG("hu %p", hu);
784 return 0;
785 }
786
787 static const struct hci_uart_proto h5p = {
788 .id = HCI_UART_3WIRE,
789 .name = "Three-wire (H5)",
790 .open = h5_open,
791 .close = h5_close,
792 .setup = h5_setup,
793 .recv = h5_recv,
794 .enqueue = h5_enqueue,
795 .dequeue = h5_dequeue,
796 .flush = h5_flush,
797 };
798
h5_serdev_probe(struct serdev_device * serdev)799 static int h5_serdev_probe(struct serdev_device *serdev)
800 {
801 const struct acpi_device_id *match;
802 struct device *dev = &serdev->dev;
803 struct h5 *h5;
804
805 h5 = devm_kzalloc(dev, sizeof(*h5), GFP_KERNEL);
806 if (!h5)
807 return -ENOMEM;
808
809 set_bit(HCI_UART_RESET_ON_INIT, &h5->serdev_hu.hdev_flags);
810
811 h5->hu = &h5->serdev_hu;
812 h5->serdev_hu.serdev = serdev;
813 serdev_device_set_drvdata(serdev, h5);
814
815 if (has_acpi_companion(dev)) {
816 match = acpi_match_device(dev->driver->acpi_match_table, dev);
817 if (!match)
818 return -ENODEV;
819
820 h5->vnd = (const struct h5_vnd *)match->driver_data;
821 h5->id = (char *)match->id;
822
823 if (h5->vnd->acpi_gpio_map)
824 devm_acpi_dev_add_driver_gpios(dev,
825 h5->vnd->acpi_gpio_map);
826 }
827
828 h5->enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);
829 if (IS_ERR(h5->enable_gpio))
830 return PTR_ERR(h5->enable_gpio);
831
832 h5->device_wake_gpio = devm_gpiod_get_optional(dev, "device-wake",
833 GPIOD_OUT_LOW);
834 if (IS_ERR(h5->device_wake_gpio))
835 return PTR_ERR(h5->device_wake_gpio);
836
837 return hci_uart_register_device(&h5->serdev_hu, &h5p);
838 }
839
h5_serdev_remove(struct serdev_device * serdev)840 static void h5_serdev_remove(struct serdev_device *serdev)
841 {
842 struct h5 *h5 = serdev_device_get_drvdata(serdev);
843
844 hci_uart_unregister_device(&h5->serdev_hu);
845 }
846
847 #ifdef CONFIG_BT_HCIUART_RTL
h5_btrtl_setup(struct h5 * h5)848 static int h5_btrtl_setup(struct h5 *h5)
849 {
850 struct btrtl_device_info *btrtl_dev;
851 struct sk_buff *skb;
852 __le32 baudrate_data;
853 u32 device_baudrate;
854 unsigned int controller_baudrate;
855 bool flow_control;
856 int err;
857
858 btrtl_dev = btrtl_initialize(h5->hu->hdev, h5->id);
859 if (IS_ERR(btrtl_dev))
860 return PTR_ERR(btrtl_dev);
861
862 err = btrtl_get_uart_settings(h5->hu->hdev, btrtl_dev,
863 &controller_baudrate, &device_baudrate,
864 &flow_control);
865 if (err)
866 goto out_free;
867
868 baudrate_data = cpu_to_le32(device_baudrate);
869 skb = __hci_cmd_sync(h5->hu->hdev, 0xfc17, sizeof(baudrate_data),
870 &baudrate_data, HCI_INIT_TIMEOUT);
871 if (IS_ERR(skb)) {
872 rtl_dev_err(h5->hu->hdev, "set baud rate command failed\n");
873 err = PTR_ERR(skb);
874 goto out_free;
875 } else {
876 kfree_skb(skb);
877 }
878 /* Give the device some time to set up the new baudrate. */
879 usleep_range(10000, 20000);
880
881 serdev_device_set_baudrate(h5->hu->serdev, controller_baudrate);
882 serdev_device_set_flow_control(h5->hu->serdev, flow_control);
883
884 err = btrtl_download_firmware(h5->hu->hdev, btrtl_dev);
885 /* Give the device some time before the hci-core sends it a reset */
886 usleep_range(10000, 20000);
887
888 /* Enable controller to do both LE scan and BR/EDR inquiry
889 * simultaneously.
890 */
891 set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &h5->hu->hdev->quirks);
892
893 out_free:
894 btrtl_free(btrtl_dev);
895
896 return err;
897 }
898
h5_btrtl_open(struct h5 * h5)899 static void h5_btrtl_open(struct h5 *h5)
900 {
901 /* Devices always start with these fixed parameters */
902 serdev_device_set_flow_control(h5->hu->serdev, false);
903 serdev_device_set_parity(h5->hu->serdev, SERDEV_PARITY_EVEN);
904 serdev_device_set_baudrate(h5->hu->serdev, 115200);
905
906 /* The controller needs up to 500ms to wakeup */
907 gpiod_set_value_cansleep(h5->enable_gpio, 1);
908 gpiod_set_value_cansleep(h5->device_wake_gpio, 1);
909 msleep(500);
910 }
911
h5_btrtl_close(struct h5 * h5)912 static void h5_btrtl_close(struct h5 *h5)
913 {
914 gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
915 gpiod_set_value_cansleep(h5->enable_gpio, 0);
916 }
917
918 static const struct acpi_gpio_params btrtl_device_wake_gpios = { 0, 0, false };
919 static const struct acpi_gpio_params btrtl_enable_gpios = { 1, 0, false };
920 static const struct acpi_gpio_params btrtl_host_wake_gpios = { 2, 0, false };
921 static const struct acpi_gpio_mapping acpi_btrtl_gpios[] = {
922 { "device-wake-gpios", &btrtl_device_wake_gpios, 1 },
923 { "enable-gpios", &btrtl_enable_gpios, 1 },
924 { "host-wake-gpios", &btrtl_host_wake_gpios, 1 },
925 {},
926 };
927
928 static struct h5_vnd rtl_vnd = {
929 .setup = h5_btrtl_setup,
930 .open = h5_btrtl_open,
931 .close = h5_btrtl_close,
932 .acpi_gpio_map = acpi_btrtl_gpios,
933 };
934 #endif
935
936 #ifdef CONFIG_ACPI
937 static const struct acpi_device_id h5_acpi_match[] = {
938 #ifdef CONFIG_BT_HCIUART_RTL
939 { "OBDA8723", (kernel_ulong_t)&rtl_vnd },
940 #endif
941 { },
942 };
943 MODULE_DEVICE_TABLE(acpi, h5_acpi_match);
944 #endif
945
946 static struct serdev_device_driver h5_serdev_driver = {
947 .probe = h5_serdev_probe,
948 .remove = h5_serdev_remove,
949 .driver = {
950 .name = "hci_uart_h5",
951 .acpi_match_table = ACPI_PTR(h5_acpi_match),
952 },
953 };
954
h5_init(void)955 int __init h5_init(void)
956 {
957 serdev_device_driver_register(&h5_serdev_driver);
958 return hci_uart_register_proto(&h5p);
959 }
960
h5_deinit(void)961 int __exit h5_deinit(void)
962 {
963 serdev_device_driver_unregister(&h5_serdev_driver);
964 return hci_uart_unregister_proto(&h5p);
965 }
966