1/*
2 *
3 * Bluetooth HCI UART driver
4 *
5 * Copyright (C) 2002-2003 Fabrizio Gennari <fabrizio.gennari@philips.com>
6 * Copyright (C) 2004-2005 Marcel Holtmann <marcel@holtmann.org>
7 *
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 *
23 */
24
25#include <linux/module.h>
26
27#include <linux/kernel.h>
28#include <linux/init.h>
29#include <linux/types.h>
30#include <linux/fcntl.h>
31#include <linux/interrupt.h>
32#include <linux/ptrace.h>
33#include <linux/poll.h>
34
35#include <linux/slab.h>
36#include <linux/tty.h>
37#include <linux/errno.h>
38#include <linux/string.h>
39#include <linux/signal.h>
40#include <linux/ioctl.h>
41#include <linux/skbuff.h>
42#include <linux/bitrev.h>
43#include <asm/unaligned.h>
44
45#include <net/bluetooth/bluetooth.h>
46#include <net/bluetooth/hci_core.h>
47
48#include "hci_uart.h"
49
50static bool txcrc = true;
51static bool hciextn = true;
52
53#define BCSP_TXWINSIZE 4
54
55#define BCSP_ACK_PKT 0x05
56#define BCSP_LE_PKT 0x06
57
58struct bcsp_struct {
59 struct sk_buff_head unack; /* Unack'ed packets queue */
60 struct sk_buff_head rel; /* Reliable packets queue */
61 struct sk_buff_head unrel; /* Unreliable packets queue */
62
63 unsigned long rx_count;
64 struct sk_buff *rx_skb;
65 u8 rxseq_txack; /* rxseq == txack. */
66 u8 rxack; /* Last packet sent by us that the peer ack'ed */
67 struct timer_list tbcsp;
68 struct hci_uart *hu;
69
70 enum {
71 BCSP_W4_PKT_DELIMITER,
72 BCSP_W4_PKT_START,
73 BCSP_W4_BCSP_HDR,
74 BCSP_W4_DATA,
75 BCSP_W4_CRC
76 } rx_state;
77
78 enum {
79 BCSP_ESCSTATE_NOESC,
80 BCSP_ESCSTATE_ESC
81 } rx_esc_state;
82
83 u8 use_crc;
84 u16 message_crc;
85 u8 txack_req; /* Do we need to send ack's to the peer? */
86
87 /* Reliable packet sequence number - used to assign seq to each rel pkt. */
88 u8 msgq_txseq;
89};
90
91/* ---- BCSP CRC calculation ---- */
92
93/* Table for calculating CRC for polynomial 0x1021, LSB processed first,
94 * initial value 0xffff, bits shifted in reverse order.
95 */
96
97static const u16 crc_table[] = {
98 0x0000, 0x1081, 0x2102, 0x3183,
99 0x4204, 0x5285, 0x6306, 0x7387,
100 0x8408, 0x9489, 0xa50a, 0xb58b,
101 0xc60c, 0xd68d, 0xe70e, 0xf78f
102};
103
104/* Initialise the crc calculator */
105#define BCSP_CRC_INIT(x) x = 0xffff
106
107/* Update crc with next data byte
108 *
109 * Implementation note
110 * The data byte is treated as two nibbles. The crc is generated
111 * in reverse, i.e., bits are fed into the register from the top.
112 */
113static void bcsp_crc_update(u16 *crc, u8 d)
114{
115 u16 reg = *crc;
116
117 reg = (reg >> 4) ^ crc_table[(reg ^ d) & 0x000f];
118 reg = (reg >> 4) ^ crc_table[(reg ^ (d >> 4)) & 0x000f];
119
120 *crc = reg;
121}
122
123/* ---- BCSP core ---- */
124
125static void bcsp_slip_msgdelim(struct sk_buff *skb)
126{
127 const char pkt_delim = 0xc0;
128
129 skb_put_data(skb, &pkt_delim, 1);
130}
131
132static void bcsp_slip_one_byte(struct sk_buff *skb, u8 c)
133{
134 const char esc_c0[2] = { 0xdb, 0xdc };
135 const char esc_db[2] = { 0xdb, 0xdd };
136
137 switch (c) {
138 case 0xc0:
139 skb_put_data(skb, &esc_c0, 2);
140 break;
141 case 0xdb:
142 skb_put_data(skb, &esc_db, 2);
143 break;
144 default:
145 skb_put_data(skb, &c, 1);
146 }
147}
148
149static int bcsp_enqueue(struct hci_uart *hu, struct sk_buff *skb)
150{
151 struct bcsp_struct *bcsp = hu->priv;
152
153 if (skb->len > 0xFFF) {
154 BT_ERR("Packet too long");
155 kfree_skb(skb);
156 return 0;
157 }
158
159 switch (hci_skb_pkt_type(skb)) {
160 case HCI_ACLDATA_PKT:
161 case HCI_COMMAND_PKT:
162 skb_queue_tail(&bcsp->rel, skb);
163 break;
164
165 case HCI_SCODATA_PKT:
166 skb_queue_tail(&bcsp->unrel, skb);
167 break;
168
169 default:
170 BT_ERR("Unknown packet type");
171 kfree_skb(skb);
172 break;
173 }
174
175 return 0;
176}
177
178static struct sk_buff *bcsp_prepare_pkt(struct bcsp_struct *bcsp, u8 *data,
179 int len, int pkt_type)
180{
181 struct sk_buff *nskb;
182 u8 hdr[4], chan;
183 u16 BCSP_CRC_INIT(bcsp_txmsg_crc);
184 int rel, i;
185
186 switch (pkt_type) {
187 case HCI_ACLDATA_PKT:
188 chan = 6; /* BCSP ACL channel */
189 rel = 1; /* reliable channel */
190 break;
191 case HCI_COMMAND_PKT:
192 chan = 5; /* BCSP cmd/evt channel */
193 rel = 1; /* reliable channel */
194 break;
195 case HCI_SCODATA_PKT:
196 chan = 7; /* BCSP SCO channel */
197 rel = 0; /* unreliable channel */
198 break;
199 case BCSP_LE_PKT:
200 chan = 1; /* BCSP LE channel */
201 rel = 0; /* unreliable channel */
202 break;
203 case BCSP_ACK_PKT:
204 chan = 0; /* BCSP internal channel */
205 rel = 0; /* unreliable channel */
206 break;
207 default:
208 BT_ERR("Unknown packet type");
209 return NULL;
210 }
211
212 if (hciextn && chan == 5) {
213 __le16 opcode = ((struct hci_command_hdr *)data)->opcode;
214
215 /* Vendor specific commands */
216 if (hci_opcode_ogf(__le16_to_cpu(opcode)) == 0x3f) {
217 u8 desc = *(data + HCI_COMMAND_HDR_SIZE);
218
219 if ((desc & 0xf0) == 0xc0) {
220 data += HCI_COMMAND_HDR_SIZE + 1;
221 len -= HCI_COMMAND_HDR_SIZE + 1;
222 chan = desc & 0x0f;
223 }
224 }
225 }
226
227 /* Max len of packet: (original len +4(bcsp hdr) +2(crc))*2
228 * (because bytes 0xc0 and 0xdb are escaped, worst case is
229 * when the packet is all made of 0xc0 and 0xdb :) )
230 * + 2 (0xc0 delimiters at start and end).
231 */
232
233 nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);
234 if (!nskb)
235 return NULL;
236
237 hci_skb_pkt_type(nskb) = pkt_type;
238
239 bcsp_slip_msgdelim(nskb);
240
241 hdr[0] = bcsp->rxseq_txack << 3;
242 bcsp->txack_req = 0;
243 BT_DBG("We request packet no %u to card", bcsp->rxseq_txack);
244
245 if (rel) {
246 hdr[0] |= 0x80 + bcsp->msgq_txseq;
247 BT_DBG("Sending packet with seqno %u", bcsp->msgq_txseq);
248 bcsp->msgq_txseq = (bcsp->msgq_txseq + 1) & 0x07;
249 }
250
251 if (bcsp->use_crc)
252 hdr[0] |= 0x40;
253
254 hdr[1] = ((len << 4) & 0xff) | chan;
255 hdr[2] = len >> 4;
256 hdr[3] = ~(hdr[0] + hdr[1] + hdr[2]);
257
258 /* Put BCSP header */
259 for (i = 0; i < 4; i++) {
260 bcsp_slip_one_byte(nskb, hdr[i]);
261
262 if (bcsp->use_crc)
263 bcsp_crc_update(&bcsp_txmsg_crc, hdr[i]);
264 }
265
266 /* Put payload */
267 for (i = 0; i < len; i++) {
268 bcsp_slip_one_byte(nskb, data[i]);
269
270 if (bcsp->use_crc)
271 bcsp_crc_update(&bcsp_txmsg_crc, data[i]);
272 }
273
274 /* Put CRC */
275 if (bcsp->use_crc) {
276 bcsp_txmsg_crc = bitrev16(bcsp_txmsg_crc);
277 bcsp_slip_one_byte(nskb, (u8)((bcsp_txmsg_crc >> 8) & 0x00ff));
278 bcsp_slip_one_byte(nskb, (u8)(bcsp_txmsg_crc & 0x00ff));
279 }
280
281 bcsp_slip_msgdelim(nskb);
282 return nskb;
283}
284
285/* This is a rewrite of pkt_avail in ABCSP */
286static struct sk_buff *bcsp_dequeue(struct hci_uart *hu)
287{
288 struct bcsp_struct *bcsp = hu->priv;
289 unsigned long flags;
290 struct sk_buff *skb;
291
292 /* First of all, check for unreliable messages in the queue,
293 * since they have priority
294 */
295
296 skb = skb_dequeue(&bcsp->unrel);
297 if (skb != NULL) {
298 struct sk_buff *nskb;
299
300 nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len,
301 hci_skb_pkt_type(skb));
302 if (nskb) {
303 kfree_skb(skb);
304 return nskb;
305 } else {
306 skb_queue_head(&bcsp->unrel, skb);
307 BT_ERR("Could not dequeue pkt because alloc_skb failed");
308 }
309 }
310
311 /* Now, try to send a reliable pkt. We can only send a
312 * reliable packet if the number of packets sent but not yet ack'ed
313 * is < than the winsize
314 */
315
316 spin_lock_irqsave_nested(&bcsp->unack.lock, flags, SINGLE_DEPTH_NESTING);
317
318 if (bcsp->unack.qlen < BCSP_TXWINSIZE) {
319 skb = skb_dequeue(&bcsp->rel);
320 if (skb != NULL) {
321 struct sk_buff *nskb;
322
323 nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len,
324 hci_skb_pkt_type(skb));
325 if (nskb) {
326 __skb_queue_tail(&bcsp->unack, skb);
327 mod_timer(&bcsp->tbcsp, jiffies + HZ / 4);
328 spin_unlock_irqrestore(&bcsp->unack.lock, flags);
329 return nskb;
330 } else {
331 skb_queue_head(&bcsp->rel, skb);
332 BT_ERR("Could not dequeue pkt because alloc_skb failed");
333 }
334 }
335 }
336
337 spin_unlock_irqrestore(&bcsp->unack.lock, flags);
338
339 /* We could not send a reliable packet, either because there are
340 * none or because there are too many unack'ed pkts. Did we receive
341 * any packets we have not acknowledged yet ?
342 */
343
344 if (bcsp->txack_req) {
345 /* if so, craft an empty ACK pkt and send it on BCSP unreliable
346 * channel 0
347 */
348 struct sk_buff *nskb = bcsp_prepare_pkt(bcsp, NULL, 0, BCSP_ACK_PKT);
349 return nskb;
350 }
351
352 /* We have nothing to send */
353 return NULL;
354}
355
356static int bcsp_flush(struct hci_uart *hu)
357{
358 BT_DBG("hu %p", hu);
359 return 0;
360}
361
362/* Remove ack'ed packets */
363static void bcsp_pkt_cull(struct bcsp_struct *bcsp)
364{
365 struct sk_buff *skb, *tmp;
366 unsigned long flags;
367 int i, pkts_to_be_removed;
368 u8 seqno;
369
370 spin_lock_irqsave(&bcsp->unack.lock, flags);
371
372 pkts_to_be_removed = skb_queue_len(&bcsp->unack);
373 seqno = bcsp->msgq_txseq;
374
375 while (pkts_to_be_removed) {
376 if (bcsp->rxack == seqno)
377 break;
378 pkts_to_be_removed--;
379 seqno = (seqno - 1) & 0x07;
380 }
381
382 if (bcsp->rxack != seqno)
383 BT_ERR("Peer acked invalid packet");
384
385 BT_DBG("Removing %u pkts out of %u, up to seqno %u",
386 pkts_to_be_removed, skb_queue_len(&bcsp->unack),
387 (seqno - 1) & 0x07);
388
389 i = 0;
390 skb_queue_walk_safe(&bcsp->unack, skb, tmp) {
391 if (i >= pkts_to_be_removed)
392 break;
393 i++;
394
395 __skb_unlink(skb, &bcsp->unack);
396 kfree_skb(skb);
397 }
398
399 if (skb_queue_empty(&bcsp->unack))
400 del_timer(&bcsp->tbcsp);
401
402 spin_unlock_irqrestore(&bcsp->unack.lock, flags);
403
404 if (i != pkts_to_be_removed)
405 BT_ERR("Removed only %u out of %u pkts", i, pkts_to_be_removed);
406}
407
408/* Handle BCSP link-establishment packets. When we
409 * detect a "sync" packet, symptom that the BT module has reset,
410 * we do nothing :) (yet)
411 */
412static void bcsp_handle_le_pkt(struct hci_uart *hu)
413{
414 struct bcsp_struct *bcsp = hu->priv;
415 u8 conf_pkt[4] = { 0xad, 0xef, 0xac, 0xed };
416 u8 conf_rsp_pkt[4] = { 0xde, 0xad, 0xd0, 0xd0 };
417 u8 sync_pkt[4] = { 0xda, 0xdc, 0xed, 0xed };
418
419 /* spot "conf" pkts and reply with a "conf rsp" pkt */
420 if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&
421 !memcmp(&bcsp->rx_skb->data[4], conf_pkt, 4)) {
422 struct sk_buff *nskb = alloc_skb(4, GFP_ATOMIC);
423
424 BT_DBG("Found a LE conf pkt");
425 if (!nskb)
426 return;
427 skb_put_data(nskb, conf_rsp_pkt, 4);
428 hci_skb_pkt_type(nskb) = BCSP_LE_PKT;
429
430 skb_queue_head(&bcsp->unrel, nskb);
431 hci_uart_tx_wakeup(hu);
432 }
433 /* Spot "sync" pkts. If we find one...disaster! */
434 else if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&
435 !memcmp(&bcsp->rx_skb->data[4], sync_pkt, 4)) {
436 BT_ERR("Found a LE sync pkt, card has reset");
437 }
438}
439
440static inline void bcsp_unslip_one_byte(struct bcsp_struct *bcsp, unsigned char byte)
441{
442 const u8 c0 = 0xc0, db = 0xdb;
443
444 switch (bcsp->rx_esc_state) {
445 case BCSP_ESCSTATE_NOESC:
446 switch (byte) {
447 case 0xdb:
448 bcsp->rx_esc_state = BCSP_ESCSTATE_ESC;
449 break;
450 default:
451 skb_put_data(bcsp->rx_skb, &byte, 1);
452 if ((bcsp->rx_skb->data[0] & 0x40) != 0 &&
453 bcsp->rx_state != BCSP_W4_CRC)
454 bcsp_crc_update(&bcsp->message_crc, byte);
455 bcsp->rx_count--;
456 }
457 break;
458
459 case BCSP_ESCSTATE_ESC:
460 switch (byte) {
461 case 0xdc:
462 skb_put_data(bcsp->rx_skb, &c0, 1);
463 if ((bcsp->rx_skb->data[0] & 0x40) != 0 &&
464 bcsp->rx_state != BCSP_W4_CRC)
465 bcsp_crc_update(&bcsp->message_crc, 0xc0);
466 bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
467 bcsp->rx_count--;
468 break;
469
470 case 0xdd:
471 skb_put_data(bcsp->rx_skb, &db, 1);
472 if ((bcsp->rx_skb->data[0] & 0x40) != 0 &&
473 bcsp->rx_state != BCSP_W4_CRC)
474 bcsp_crc_update(&bcsp->message_crc, 0xdb);
475 bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
476 bcsp->rx_count--;
477 break;
478
479 default:
480 BT_ERR("Invalid byte %02x after esc byte", byte);
481 kfree_skb(bcsp->rx_skb);
482 bcsp->rx_skb = NULL;
483 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
484 bcsp->rx_count = 0;
485 }
486 }
487}
488
489static void bcsp_complete_rx_pkt(struct hci_uart *hu)
490{
491 struct bcsp_struct *bcsp = hu->priv;
492 int pass_up = 0;
493
494 if (bcsp->rx_skb->data[0] & 0x80) { /* reliable pkt */
495 BT_DBG("Received seqno %u from card", bcsp->rxseq_txack);
496
497 /* check the rx sequence number is as expected */
498 if ((bcsp->rx_skb->data[0] & 0x07) == bcsp->rxseq_txack) {
499 bcsp->rxseq_txack++;
500 bcsp->rxseq_txack %= 0x8;
501 } else {
502 /* handle re-transmitted packet or
503 * when packet was missed
504 */
505 BT_ERR("Out-of-order packet arrived, got %u expected %u",
506 bcsp->rx_skb->data[0] & 0x07, bcsp->rxseq_txack);
507
508 /* do not process out-of-order packet payload */
509 pass_up = 2;
510 }
511
512 /* send current txack value to all received reliable packets */
513 bcsp->txack_req = 1;
514
515 /* If needed, transmit an ack pkt */
516 hci_uart_tx_wakeup(hu);
517 }
518
519 bcsp->rxack = (bcsp->rx_skb->data[0] >> 3) & 0x07;
520 BT_DBG("Request for pkt %u from card", bcsp->rxack);
521
522 /* handle received ACK indications,
523 * including those from out-of-order packets
524 */
525 bcsp_pkt_cull(bcsp);
526
527 if (pass_up != 2) {
528 if ((bcsp->rx_skb->data[1] & 0x0f) == 6 &&
529 (bcsp->rx_skb->data[0] & 0x80)) {
530 hci_skb_pkt_type(bcsp->rx_skb) = HCI_ACLDATA_PKT;
531 pass_up = 1;
532 } else if ((bcsp->rx_skb->data[1] & 0x0f) == 5 &&
533 (bcsp->rx_skb->data[0] & 0x80)) {
534 hci_skb_pkt_type(bcsp->rx_skb) = HCI_EVENT_PKT;
535 pass_up = 1;
536 } else if ((bcsp->rx_skb->data[1] & 0x0f) == 7) {
537 hci_skb_pkt_type(bcsp->rx_skb) = HCI_SCODATA_PKT;
538 pass_up = 1;
539 } else if ((bcsp->rx_skb->data[1] & 0x0f) == 1 &&
540 !(bcsp->rx_skb->data[0] & 0x80)) {
541 bcsp_handle_le_pkt(hu);
542 pass_up = 0;
543 } else {
544 pass_up = 0;
545 }
546 }
547
548 if (pass_up == 0) {
549 struct hci_event_hdr hdr;
550 u8 desc = (bcsp->rx_skb->data[1] & 0x0f);
551
552 if (desc != 0 && desc != 1) {
553 if (hciextn) {
554 desc |= 0xc0;
555 skb_pull(bcsp->rx_skb, 4);
556 memcpy(skb_push(bcsp->rx_skb, 1), &desc, 1);
557
558 hdr.evt = 0xff;
559 hdr.plen = bcsp->rx_skb->len;
560 memcpy(skb_push(bcsp->rx_skb, HCI_EVENT_HDR_SIZE), &hdr, HCI_EVENT_HDR_SIZE);
561 hci_skb_pkt_type(bcsp->rx_skb) = HCI_EVENT_PKT;
562
563 hci_recv_frame(hu->hdev, bcsp->rx_skb);
564 } else {
565 BT_ERR("Packet for unknown channel (%u %s)",
566 bcsp->rx_skb->data[1] & 0x0f,
567 bcsp->rx_skb->data[0] & 0x80 ?
568 "reliable" : "unreliable");
569 kfree_skb(bcsp->rx_skb);
570 }
571 } else
572 kfree_skb(bcsp->rx_skb);
573 } else if (pass_up == 1) {
574 /* Pull out BCSP hdr */
575 skb_pull(bcsp->rx_skb, 4);
576
577 hci_recv_frame(hu->hdev, bcsp->rx_skb);
578 } else {
579 /* ignore packet payload of already ACKed re-transmitted
580 * packets or when a packet was missed in the BCSP window
581 */
582 kfree_skb(bcsp->rx_skb);
583 }
584
585 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
586 bcsp->rx_skb = NULL;
587}
588
589static u16 bscp_get_crc(struct bcsp_struct *bcsp)
590{
591 return get_unaligned_be16(&bcsp->rx_skb->data[bcsp->rx_skb->len - 2]);
592}
593
594/* Recv data */
595static int bcsp_recv(struct hci_uart *hu, const void *data, int count)
596{
597 struct bcsp_struct *bcsp = hu->priv;
598 const unsigned char *ptr;
599
600 BT_DBG("hu %p count %d rx_state %d rx_count %ld",
601 hu, count, bcsp->rx_state, bcsp->rx_count);
602
603 ptr = data;
604 while (count) {
605 if (bcsp->rx_count) {
606 if (*ptr == 0xc0) {
607 BT_ERR("Short BCSP packet");
608 kfree_skb(bcsp->rx_skb);
609 bcsp->rx_state = BCSP_W4_PKT_START;
610 bcsp->rx_count = 0;
611 } else
612 bcsp_unslip_one_byte(bcsp, *ptr);
613
614 ptr++; count--;
615 continue;
616 }
617
618 switch (bcsp->rx_state) {
619 case BCSP_W4_BCSP_HDR:
620 if ((0xff & (u8)~(bcsp->rx_skb->data[0] + bcsp->rx_skb->data[1] +
621 bcsp->rx_skb->data[2])) != bcsp->rx_skb->data[3]) {
622 BT_ERR("Error in BCSP hdr checksum");
623 kfree_skb(bcsp->rx_skb);
624 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
625 bcsp->rx_count = 0;
626 continue;
627 }
628 bcsp->rx_state = BCSP_W4_DATA;
629 bcsp->rx_count = (bcsp->rx_skb->data[1] >> 4) +
630 (bcsp->rx_skb->data[2] << 4); /* May be 0 */
631 continue;
632
633 case BCSP_W4_DATA:
634 if (bcsp->rx_skb->data[0] & 0x40) { /* pkt with crc */
635 bcsp->rx_state = BCSP_W4_CRC;
636 bcsp->rx_count = 2;
637 } else
638 bcsp_complete_rx_pkt(hu);
639 continue;
640
641 case BCSP_W4_CRC:
642 if (bitrev16(bcsp->message_crc) != bscp_get_crc(bcsp)) {
643 BT_ERR("Checksum failed: computed %04x received %04x",
644 bitrev16(bcsp->message_crc),
645 bscp_get_crc(bcsp));
646
647 kfree_skb(bcsp->rx_skb);
648 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
649 bcsp->rx_count = 0;
650 continue;
651 }
652 skb_trim(bcsp->rx_skb, bcsp->rx_skb->len - 2);
653 bcsp_complete_rx_pkt(hu);
654 continue;
655
656 case BCSP_W4_PKT_DELIMITER:
657 switch (*ptr) {
658 case 0xc0:
659 bcsp->rx_state = BCSP_W4_PKT_START;
660 break;
661 default:
662 /*BT_ERR("Ignoring byte %02x", *ptr);*/
663 break;
664 }
665 ptr++; count--;
666 break;
667
668 case BCSP_W4_PKT_START:
669 switch (*ptr) {
670 case 0xc0:
671 ptr++; count--;
672 break;
673
674 default:
675 bcsp->rx_state = BCSP_W4_BCSP_HDR;
676 bcsp->rx_count = 4;
677 bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
678 BCSP_CRC_INIT(bcsp->message_crc);
679
680 /* Do not increment ptr or decrement count
681 * Allocate packet. Max len of a BCSP pkt=
682 * 0xFFF (payload) +4 (header) +2 (crc)
683 */
684
685 bcsp->rx_skb = bt_skb_alloc(0x1005, GFP_ATOMIC);
686 if (!bcsp->rx_skb) {
687 BT_ERR("Can't allocate mem for new packet");
688 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
689 bcsp->rx_count = 0;
690 return 0;
691 }
692 break;
693 }
694 break;
695 }
696 }
697 return count;
698}
699
700 /* Arrange to retransmit all messages in the relq. */
701static void bcsp_timed_event(struct timer_list *t)
702{
703 struct bcsp_struct *bcsp = from_timer(bcsp, t, tbcsp);
704 struct hci_uart *hu = bcsp->hu;
705 struct sk_buff *skb;
706 unsigned long flags;
707
708 BT_DBG("hu %p retransmitting %u pkts", hu, bcsp->unack.qlen);
709
710 spin_lock_irqsave_nested(&bcsp->unack.lock, flags, SINGLE_DEPTH_NESTING);
711
712 while ((skb = __skb_dequeue_tail(&bcsp->unack)) != NULL) {
713 bcsp->msgq_txseq = (bcsp->msgq_txseq - 1) & 0x07;
714 skb_queue_head(&bcsp->rel, skb);
715 }
716
717 spin_unlock_irqrestore(&bcsp->unack.lock, flags);
718
719 hci_uart_tx_wakeup(hu);
720}
721
722static int bcsp_open(struct hci_uart *hu)
723{
724 struct bcsp_struct *bcsp;
725
726 BT_DBG("hu %p", hu);
727
728 bcsp = kzalloc(sizeof(*bcsp), GFP_KERNEL);
729 if (!bcsp)
730 return -ENOMEM;
731
732 hu->priv = bcsp;
733 bcsp->hu = hu;
734 skb_queue_head_init(&bcsp->unack);
735 skb_queue_head_init(&bcsp->rel);
736 skb_queue_head_init(&bcsp->unrel);
737
738 timer_setup(&bcsp->tbcsp, bcsp_timed_event, 0);
739
740 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
741
742 if (txcrc)
743 bcsp->use_crc = 1;
744
745 return 0;
746}
747
748static int bcsp_close(struct hci_uart *hu)
749{
750 struct bcsp_struct *bcsp = hu->priv;
751
752 del_timer_sync(&bcsp->tbcsp);
753
754 hu->priv = NULL;
755
756 BT_DBG("hu %p", hu);
757
758 skb_queue_purge(&bcsp->unack);
759 skb_queue_purge(&bcsp->rel);
760 skb_queue_purge(&bcsp->unrel);
761
762 kfree(bcsp);
763 return 0;
764}
765
766static const struct hci_uart_proto bcsp = {
767 .id = HCI_UART_BCSP,
768 .name = "BCSP",
769 .open = bcsp_open,
770 .close = bcsp_close,
771 .enqueue = bcsp_enqueue,
772 .dequeue = bcsp_dequeue,
773 .recv = bcsp_recv,
774 .flush = bcsp_flush
775};
776
777int __init bcsp_init(void)
778{
779 return hci_uart_register_proto(&bcsp);
780}
781
782int __exit bcsp_deinit(void)
783{
784 return hci_uart_unregister_proto(&bcsp);
785}
786
787module_param(txcrc, bool, 0644);
788MODULE_PARM_DESC(txcrc, "Transmit CRC with every BCSP packet");
789
790module_param(hciextn, bool, 0644);
791MODULE_PARM_DESC(hciextn, "Convert HCI Extensions into BCSP packets");
792