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r8152: fix tx packets accounting
[linux/fpc-iii.git] / drivers / bluetooth / hci_h5.c
blob0879d64b1caf58afb6e5d494c07d9ab7e7cdf983
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/kernel.h>
25 #include <linux/errno.h>
26 #include <linux/skbuff.h>
27
28 #include <net/bluetooth/bluetooth.h>
29 #include <net/bluetooth/hci_core.h>
30
31 #include "hci_uart.h"
32
33 #define HCI_3WIRE_ACK_PKT 0
34 #define HCI_3WIRE_LINK_PKT 15
35
36 /* Sliding window size */
37 #define H5_TX_WIN_MAX 4
38
39 #define H5_ACK_TIMEOUT msecs_to_jiffies(250)
40 #define H5_SYNC_TIMEOUT msecs_to_jiffies(100)
41
42 /*
43 * Maximum Three-wire packet:
44 * 4 byte header + max value for 12-bit length + 2 bytes for CRC
45 */
46 #define H5_MAX_LEN (4 + 0xfff + 2)
47
48 /* Convenience macros for reading Three-wire header values */
49 #define H5_HDR_SEQ(hdr) ((hdr)[0] & 0x07)
50 #define H5_HDR_ACK(hdr) (((hdr)[0] >> 3) & 0x07)
51 #define H5_HDR_CRC(hdr) (((hdr)[0] >> 6) & 0x01)
52 #define H5_HDR_RELIABLE(hdr) (((hdr)[0] >> 7) & 0x01)
53 #define H5_HDR_PKT_TYPE(hdr) ((hdr)[1] & 0x0f)
54 #define H5_HDR_LEN(hdr) ((((hdr)[1] >> 4) & 0x0f) + ((hdr)[2] << 4))
55
56 #define SLIP_DELIMITER 0xc0
57 #define SLIP_ESC 0xdb
58 #define SLIP_ESC_DELIM 0xdc
59 #define SLIP_ESC_ESC 0xdd
60
61 /* H5 state flags */
62 enum {
63 H5_RX_ESC, /* SLIP escape mode */
64 H5_TX_ACK_REQ, /* Pending ack to send */
65 };
66
67 struct h5 {
68 struct sk_buff_head unack; /* Unack'ed packets queue */
69 struct sk_buff_head rel; /* Reliable packets queue */
70 struct sk_buff_head unrel; /* Unreliable packets queue */
71
72 unsigned long flags;
73
74 struct sk_buff *rx_skb; /* Receive buffer */
75 size_t rx_pending; /* Expecting more bytes */
76 u8 rx_ack; /* Last ack number received */
77
78 int (*rx_func)(struct hci_uart *hu, u8 c);
79
80 struct timer_list timer; /* Retransmission timer */
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
99 static void h5_reset_rx(struct h5 *h5);
100
101 static void h5_link_control(struct hci_uart *hu, const void *data, size_t len)
102 {
103 struct h5 *h5 = hu->priv;
104 struct sk_buff *nskb;
105
106 nskb = alloc_skb(3, GFP_ATOMIC);
107 if (!nskb)
108 return;
109
110 hci_skb_pkt_type(nskb) = HCI_3WIRE_LINK_PKT;
111
112 memcpy(skb_put(nskb, len), data, len);
113
114 skb_queue_tail(&h5->unrel, nskb);
115 }
116
117 static u8 h5_cfg_field(struct h5 *h5)
118 {
119 /* Sliding window size (first 3 bits) */
120 return h5->tx_win & 0x07;
121 }
122
123 static void h5_timed_event(unsigned long arg)
124 {
125 const unsigned char sync_req[] = { 0x01, 0x7e };
126 unsigned char conf_req[3] = { 0x03, 0xfc };
127 struct hci_uart *hu = (struct hci_uart *)arg;
128 struct h5 *h5 = hu->priv;
129 struct sk_buff *skb;
130 unsigned long flags;
131
132 BT_DBG("%s", hu->hdev->name);
133
134 if (h5->state == H5_UNINITIALIZED)
135 h5_link_control(hu, sync_req, sizeof(sync_req));
136
137 if (h5->state == H5_INITIALIZED) {
138 conf_req[2] = h5_cfg_field(h5);
139 h5_link_control(hu, conf_req, sizeof(conf_req));
140 }
141
142 if (h5->state != H5_ACTIVE) {
143 mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT);
144 goto wakeup;
145 }
146
147 if (h5->sleep != H5_AWAKE) {
148 h5->sleep = H5_SLEEPING;
149 goto wakeup;
150 }
151
152 BT_DBG("hu %p retransmitting %u pkts", hu, h5->unack.qlen);
153
154 spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);
155
156 while ((skb = __skb_dequeue_tail(&h5->unack)) != NULL) {
157 h5->tx_seq = (h5->tx_seq - 1) & 0x07;
158 skb_queue_head(&h5->rel, skb);
159 }
160
161 spin_unlock_irqrestore(&h5->unack.lock, flags);
162
163 wakeup:
164 hci_uart_tx_wakeup(hu);
165 }
166
167 static void h5_peer_reset(struct hci_uart *hu)
168 {
169 struct h5 *h5 = hu->priv;
170
171 BT_ERR("Peer device has reset");
172
173 h5->state = H5_UNINITIALIZED;
174
175 del_timer(&h5->timer);
176
177 skb_queue_purge(&h5->rel);
178 skb_queue_purge(&h5->unrel);
179 skb_queue_purge(&h5->unack);
180
181 h5->tx_seq = 0;
182 h5->tx_ack = 0;
183
184 /* Send reset request to upper stack */
185 hci_reset_dev(hu->hdev);
186 }
187
188 static int h5_open(struct hci_uart *hu)
189 {
190 struct h5 *h5;
191 const unsigned char sync[] = { 0x01, 0x7e };
192
193 BT_DBG("hu %p", hu);
194
195 h5 = kzalloc(sizeof(*h5), GFP_KERNEL);
196 if (!h5)
197 return -ENOMEM;
198
199 hu->priv = h5;
200
201 skb_queue_head_init(&h5->unack);
202 skb_queue_head_init(&h5->rel);
203 skb_queue_head_init(&h5->unrel);
204
205 h5_reset_rx(h5);
206
207 init_timer(&h5->timer);
208 h5->timer.function = h5_timed_event;
209 h5->timer.data = (unsigned long)hu;
210
211 h5->tx_win = H5_TX_WIN_MAX;
212
213 set_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags);
214
215 /* Send initial sync request */
216 h5_link_control(hu, sync, sizeof(sync));
217 mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT);
218
219 return 0;
220 }
221
222 static int h5_close(struct hci_uart *hu)
223 {
224 struct h5 *h5 = hu->priv;
225
226 del_timer_sync(&h5->timer);
227
228 skb_queue_purge(&h5->unack);
229 skb_queue_purge(&h5->rel);
230 skb_queue_purge(&h5->unrel);
231
232 kfree(h5);
233
234 return 0;
235 }
236
237 static void h5_pkt_cull(struct h5 *h5)
238 {
239 struct sk_buff *skb, *tmp;
240 unsigned long flags;
241 int i, to_remove;
242 u8 seq;
243
244 spin_lock_irqsave(&h5->unack.lock, flags);
245
246 to_remove = skb_queue_len(&h5->unack);
247 if (to_remove == 0)
248 goto unlock;
249
250 seq = h5->tx_seq;
251
252 while (to_remove > 0) {
253 if (h5->rx_ack == seq)
254 break;
255
256 to_remove--;
257 seq = (seq - 1) & 0x07;
258 }
259
260 if (seq != h5->rx_ack)
261 BT_ERR("Controller acked invalid packet");
262
263 i = 0;
264 skb_queue_walk_safe(&h5->unack, skb, tmp) {
265 if (i++ >= to_remove)
266 break;
267
268 __skb_unlink(skb, &h5->unack);
269 kfree_skb(skb);
270 }
271
272 if (skb_queue_empty(&h5->unack))
273 del_timer(&h5->timer);
274
275 unlock:
276 spin_unlock_irqrestore(&h5->unack.lock, flags);
277 }
278
279 static void h5_handle_internal_rx(struct hci_uart *hu)
280 {
281 struct h5 *h5 = hu->priv;
282 const unsigned char sync_req[] = { 0x01, 0x7e };
283 const unsigned char sync_rsp[] = { 0x02, 0x7d };
284 unsigned char conf_req[3] = { 0x03, 0xfc };
285 const unsigned char conf_rsp[] = { 0x04, 0x7b };
286 const unsigned char wakeup_req[] = { 0x05, 0xfa };
287 const unsigned char woken_req[] = { 0x06, 0xf9 };
288 const unsigned char sleep_req[] = { 0x07, 0x78 };
289 const unsigned char *hdr = h5->rx_skb->data;
290 const unsigned char *data = &h5->rx_skb->data[4];
291
292 BT_DBG("%s", hu->hdev->name);
293
294 if (H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT)
295 return;
296
297 if (H5_HDR_LEN(hdr) < 2)
298 return;
299
300 conf_req[2] = h5_cfg_field(h5);
301
302 if (memcmp(data, sync_req, 2) == 0) {
303 if (h5->state == H5_ACTIVE)
304 h5_peer_reset(hu);
305 h5_link_control(hu, sync_rsp, 2);
306 } else if (memcmp(data, sync_rsp, 2) == 0) {
307 if (h5->state == H5_ACTIVE)
308 h5_peer_reset(hu);
309 h5->state = H5_INITIALIZED;
310 h5_link_control(hu, conf_req, 3);
311 } else if (memcmp(data, conf_req, 2) == 0) {
312 h5_link_control(hu, conf_rsp, 2);
313 h5_link_control(hu, conf_req, 3);
314 } else if (memcmp(data, conf_rsp, 2) == 0) {
315 if (H5_HDR_LEN(hdr) > 2)
316 h5->tx_win = (data[2] & 0x07);
317 BT_DBG("Three-wire init complete. tx_win %u", h5->tx_win);
318 h5->state = H5_ACTIVE;
319 hci_uart_init_ready(hu);
320 return;
321 } else if (memcmp(data, sleep_req, 2) == 0) {
322 BT_DBG("Peer went to sleep");
323 h5->sleep = H5_SLEEPING;
324 return;
325 } else if (memcmp(data, woken_req, 2) == 0) {
326 BT_DBG("Peer woke up");
327 h5->sleep = H5_AWAKE;
328 } else if (memcmp(data, wakeup_req, 2) == 0) {
329 BT_DBG("Peer requested wakeup");
330 h5_link_control(hu, woken_req, 2);
331 h5->sleep = H5_AWAKE;
332 } else {
333 BT_DBG("Link Control: 0x%02hhx 0x%02hhx", data[0], data[1]);
334 return;
335 }
336
337 hci_uart_tx_wakeup(hu);
338 }
339
340 static void h5_complete_rx_pkt(struct hci_uart *hu)
341 {
342 struct h5 *h5 = hu->priv;
343 const unsigned char *hdr = h5->rx_skb->data;
344
345 if (H5_HDR_RELIABLE(hdr)) {
346 h5->tx_ack = (h5->tx_ack + 1) % 8;
347 set_bit(H5_TX_ACK_REQ, &h5->flags);
348 hci_uart_tx_wakeup(hu);
349 }
350
351 h5->rx_ack = H5_HDR_ACK(hdr);
352
353 h5_pkt_cull(h5);
354
355 switch (H5_HDR_PKT_TYPE(hdr)) {
356 case HCI_EVENT_PKT:
357 case HCI_ACLDATA_PKT:
358 case HCI_SCODATA_PKT:
359 hci_skb_pkt_type(h5->rx_skb) = H5_HDR_PKT_TYPE(hdr);
360
361 /* Remove Three-wire header */
362 skb_pull(h5->rx_skb, 4);
363
364 hci_recv_frame(hu->hdev, h5->rx_skb);
365 h5->rx_skb = NULL;
366
367 break;
368
369 default:
370 h5_handle_internal_rx(hu);
371 break;
372 }
373
374 h5_reset_rx(h5);
375 }
376
377 static int h5_rx_crc(struct hci_uart *hu, unsigned char c)
378 {
379 h5_complete_rx_pkt(hu);
380
381 return 0;
382 }
383
384 static int h5_rx_payload(struct hci_uart *hu, unsigned char c)
385 {
386 struct h5 *h5 = hu->priv;
387 const unsigned char *hdr = h5->rx_skb->data;
388
389 if (H5_HDR_CRC(hdr)) {
390 h5->rx_func = h5_rx_crc;
391 h5->rx_pending = 2;
392 } else {
393 h5_complete_rx_pkt(hu);
394 }
395
396 return 0;
397 }
398
399 static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c)
400 {
401 struct h5 *h5 = hu->priv;
402 const unsigned char *hdr = h5->rx_skb->data;
403
404 BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u",
405 hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
406 H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
407 H5_HDR_LEN(hdr));
408
409 if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) {
410 BT_ERR("Invalid header checksum");
411 h5_reset_rx(h5);
412 return 0;
413 }
414
415 if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) {
416 BT_ERR("Out-of-order packet arrived (%u != %u)",
417 H5_HDR_SEQ(hdr), h5->tx_ack);
418 h5_reset_rx(h5);
419 return 0;
420 }
421
422 if (h5->state != H5_ACTIVE &&
423 H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) {
424 BT_ERR("Non-link packet received in non-active state");
425 h5_reset_rx(h5);
426 return 0;
427 }
428
429 h5->rx_func = h5_rx_payload;
430 h5->rx_pending = H5_HDR_LEN(hdr);
431
432 return 0;
433 }
434
435 static int h5_rx_pkt_start(struct hci_uart *hu, unsigned char c)
436 {
437 struct h5 *h5 = hu->priv;
438
439 if (c == SLIP_DELIMITER)
440 return 1;
441
442 h5->rx_func = h5_rx_3wire_hdr;
443 h5->rx_pending = 4;
444
445 h5->rx_skb = bt_skb_alloc(H5_MAX_LEN, GFP_ATOMIC);
446 if (!h5->rx_skb) {
447 BT_ERR("Can't allocate mem for new packet");
448 h5_reset_rx(h5);
449 return -ENOMEM;
450 }
451
452 h5->rx_skb->dev = (void *)hu->hdev;
453
454 return 0;
455 }
456
457 static int h5_rx_delimiter(struct hci_uart *hu, unsigned char c)
458 {
459 struct h5 *h5 = hu->priv;
460
461 if (c == SLIP_DELIMITER)
462 h5->rx_func = h5_rx_pkt_start;
463
464 return 1;
465 }
466
467 static void h5_unslip_one_byte(struct h5 *h5, unsigned char c)
468 {
469 const u8 delim = SLIP_DELIMITER, esc = SLIP_ESC;
470 const u8 *byte = &c;
471
472 if (!test_bit(H5_RX_ESC, &h5->flags) && c == SLIP_ESC) {
473 set_bit(H5_RX_ESC, &h5->flags);
474 return;
475 }
476
477 if (test_and_clear_bit(H5_RX_ESC, &h5->flags)) {
478 switch (c) {
479 case SLIP_ESC_DELIM:
480 byte = &delim;
481 break;
482 case SLIP_ESC_ESC:
483 byte = &esc;
484 break;
485 default:
486 BT_ERR("Invalid esc byte 0x%02hhx", c);
487 h5_reset_rx(h5);
488 return;
489 }
490 }
491
492 memcpy(skb_put(h5->rx_skb, 1), byte, 1);
493 h5->rx_pending--;
494
495 BT_DBG("unsliped 0x%02hhx, rx_pending %zu", *byte, h5->rx_pending);
496 }
497
498 static void h5_reset_rx(struct h5 *h5)
499 {
500 if (h5->rx_skb) {
501 kfree_skb(h5->rx_skb);
502 h5->rx_skb = NULL;
503 }
504
505 h5->rx_func = h5_rx_delimiter;
506 h5->rx_pending = 0;
507 clear_bit(H5_RX_ESC, &h5->flags);
508 }
509
510 static int h5_recv(struct hci_uart *hu, const void *data, int count)
511 {
512 struct h5 *h5 = hu->priv;
513 const unsigned char *ptr = data;
514
515 BT_DBG("%s pending %zu count %d", hu->hdev->name, h5->rx_pending,
516 count);
517
518 while (count > 0) {
519 int processed;
520
521 if (h5->rx_pending > 0) {
522 if (*ptr == SLIP_DELIMITER) {
523 BT_ERR("Too short H5 packet");
524 h5_reset_rx(h5);
525 continue;
526 }
527
528 h5_unslip_one_byte(h5, *ptr);
529
530 ptr++; count--;
531 continue;
532 }
533
534 processed = h5->rx_func(hu, *ptr);
535 if (processed < 0)
536 return processed;
537
538 ptr += processed;
539 count -= processed;
540 }
541
542 return 0;
543 }
544
545 static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb)
546 {
547 struct h5 *h5 = hu->priv;
548
549 if (skb->len > 0xfff) {
550 BT_ERR("Packet too long (%u bytes)", skb->len);
551 kfree_skb(skb);
552 return 0;
553 }
554
555 if (h5->state != H5_ACTIVE) {
556 BT_ERR("Ignoring HCI data in non-active state");
557 kfree_skb(skb);
558 return 0;
559 }
560
561 switch (hci_skb_pkt_type(skb)) {
562 case HCI_ACLDATA_PKT:
563 case HCI_COMMAND_PKT:
564 skb_queue_tail(&h5->rel, skb);
565 break;
566
567 case HCI_SCODATA_PKT:
568 skb_queue_tail(&h5->unrel, skb);
569 break;
570
571 default:
572 BT_ERR("Unknown packet type %u", hci_skb_pkt_type(skb));
573 kfree_skb(skb);
574 break;
575 }
576
577 return 0;
578 }
579
580 static void h5_slip_delim(struct sk_buff *skb)
581 {
582 const char delim = SLIP_DELIMITER;
583
584 memcpy(skb_put(skb, 1), &delim, 1);
585 }
586
587 static void h5_slip_one_byte(struct sk_buff *skb, u8 c)
588 {
589 const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM };
590 const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC };
591
592 switch (c) {
593 case SLIP_DELIMITER:
594 memcpy(skb_put(skb, 2), &esc_delim, 2);
595 break;
596 case SLIP_ESC:
597 memcpy(skb_put(skb, 2), &esc_esc, 2);
598 break;
599 default:
600 memcpy(skb_put(skb, 1), &c, 1);
601 }
602 }
603
604 static bool valid_packet_type(u8 type)
605 {
606 switch (type) {
607 case HCI_ACLDATA_PKT:
608 case HCI_COMMAND_PKT:
609 case HCI_SCODATA_PKT:
610 case HCI_3WIRE_LINK_PKT:
611 case HCI_3WIRE_ACK_PKT:
612 return true;
613 default:
614 return false;
615 }
616 }
617
618 static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type,
619 const u8 *data, size_t len)
620 {
621 struct h5 *h5 = hu->priv;
622 struct sk_buff *nskb;
623 u8 hdr[4];
624 int i;
625
626 if (!valid_packet_type(pkt_type)) {
627 BT_ERR("Unknown packet type %u", pkt_type);
628 return NULL;
629 }
630
631 /*
632 * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2
633 * (because bytes 0xc0 and 0xdb are escaped, worst case is when
634 * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0
635 * delimiters at start and end).
636 */
637 nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);
638 if (!nskb)
639 return NULL;
640
641 hci_skb_pkt_type(nskb) = pkt_type;
642
643 h5_slip_delim(nskb);
644
645 hdr[0] = h5->tx_ack << 3;
646 clear_bit(H5_TX_ACK_REQ, &h5->flags);
647
648 /* Reliable packet? */
649 if (pkt_type == HCI_ACLDATA_PKT || pkt_type == HCI_COMMAND_PKT) {
650 hdr[0] |= 1 << 7;
651 hdr[0] |= h5->tx_seq;
652 h5->tx_seq = (h5->tx_seq + 1) % 8;
653 }
654
655 hdr[1] = pkt_type | ((len & 0x0f) << 4);
656 hdr[2] = len >> 4;
657 hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff);
658
659 BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u",
660 hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
661 H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
662 H5_HDR_LEN(hdr));
663
664 for (i = 0; i < 4; i++)
665 h5_slip_one_byte(nskb, hdr[i]);
666
667 for (i = 0; i < len; i++)
668 h5_slip_one_byte(nskb, data[i]);
669
670 h5_slip_delim(nskb);
671
672 return nskb;
673 }
674
675 static struct sk_buff *h5_dequeue(struct hci_uart *hu)
676 {
677 struct h5 *h5 = hu->priv;
678 unsigned long flags;
679 struct sk_buff *skb, *nskb;
680
681 if (h5->sleep != H5_AWAKE) {
682 const unsigned char wakeup_req[] = { 0x05, 0xfa };
683
684 if (h5->sleep == H5_WAKING_UP)
685 return NULL;
686
687 h5->sleep = H5_WAKING_UP;
688 BT_DBG("Sending wakeup request");
689
690 mod_timer(&h5->timer, jiffies + HZ / 100);
691 return h5_prepare_pkt(hu, HCI_3WIRE_LINK_PKT, wakeup_req, 2);
692 }
693
694 skb = skb_dequeue(&h5->unrel);
695 if (skb) {
696 nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
697 skb->data, skb->len);
698 if (nskb) {
699 kfree_skb(skb);
700 return nskb;
701 }
702
703 skb_queue_head(&h5->unrel, skb);
704 BT_ERR("Could not dequeue pkt because alloc_skb failed");
705 }
706
707 spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);
708
709 if (h5->unack.qlen >= h5->tx_win)
710 goto unlock;
711
712 skb = skb_dequeue(&h5->rel);
713 if (skb) {
714 nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
715 skb->data, skb->len);
716 if (nskb) {
717 __skb_queue_tail(&h5->unack, skb);
718 mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT);
719 spin_unlock_irqrestore(&h5->unack.lock, flags);
720 return nskb;
721 }
722
723 skb_queue_head(&h5->rel, skb);
724 BT_ERR("Could not dequeue pkt because alloc_skb failed");
725 }
726
727 unlock:
728 spin_unlock_irqrestore(&h5->unack.lock, flags);
729
730 if (test_bit(H5_TX_ACK_REQ, &h5->flags))
731 return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0);
732
733 return NULL;
734 }
735
736 static int h5_flush(struct hci_uart *hu)
737 {
738 BT_DBG("hu %p", hu);
739 return 0;
740 }
741
742 static const struct hci_uart_proto h5p = {
743 .id = HCI_UART_3WIRE,
744 .name = "Three-wire (H5)",
745 .open = h5_open,
746 .close = h5_close,
747 .recv = h5_recv,
748 .enqueue = h5_enqueue,
749 .dequeue = h5_dequeue,
750 .flush = h5_flush,
751 };
752
753 int __init h5_init(void)
754 {
755 return hci_uart_register_proto(&h5p);
756 }
757
758 int __exit h5_deinit(void)
759 {
760 return hci_uart_unregister_proto(&h5p);
761 }
Linux with added FPC-III support