staging: iio: ad7606: fix improper setting of oversampling pins
[linux/fpc-iii.git] / drivers / bluetooth / hci_bcsp.c
bloba2c921faaa12e537fbdd170bbd7cb1167f5ceb7a
1 /*
3 * Bluetooth HCI UART driver
5 * Copyright (C) 2002-2003 Fabrizio Gennari <fabrizio.gennari@philips.com>
6 * Copyright (C) 2004-2005 Marcel Holtmann <marcel@holtmann.org>
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.
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.
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
25 #include <linux/module.h>
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>
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>
45 #include <net/bluetooth/bluetooth.h>
46 #include <net/bluetooth/hci_core.h>
48 #include "hci_uart.h"
50 static bool txcrc = true;
51 static bool hciextn = true;
53 #define BCSP_TXWINSIZE 4
55 #define BCSP_ACK_PKT 0x05
56 #define BCSP_LE_PKT 0x06
58 struct 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 */
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;
69 enum {
70 BCSP_W4_PKT_DELIMITER,
71 BCSP_W4_PKT_START,
72 BCSP_W4_BCSP_HDR,
73 BCSP_W4_DATA,
74 BCSP_W4_CRC
75 } rx_state;
77 enum {
78 BCSP_ESCSTATE_NOESC,
79 BCSP_ESCSTATE_ESC
80 } rx_esc_state;
82 u8 use_crc;
83 u16 message_crc;
84 u8 txack_req; /* Do we need to send ack's to the peer? */
86 /* Reliable packet sequence number - used to assign seq to each rel pkt. */
87 u8 msgq_txseq;
90 /* ---- BCSP CRC calculation ---- */
92 /* Table for calculating CRC for polynomial 0x1021, LSB processed first,
93 * initial value 0xffff, bits shifted in reverse order.
96 static const u16 crc_table[] = {
97 0x0000, 0x1081, 0x2102, 0x3183,
98 0x4204, 0x5285, 0x6306, 0x7387,
99 0x8408, 0x9489, 0xa50a, 0xb58b,
100 0xc60c, 0xd68d, 0xe70e, 0xf78f
103 /* Initialise the crc calculator */
104 #define BCSP_CRC_INIT(x) x = 0xffff
106 /* Update crc with next data byte
108 * Implementation note
109 * The data byte is treated as two nibbles. The crc is generated
110 * in reverse, i.e., bits are fed into the register from the top.
112 static void bcsp_crc_update(u16 *crc, u8 d)
114 u16 reg = *crc;
116 reg = (reg >> 4) ^ crc_table[(reg ^ d) & 0x000f];
117 reg = (reg >> 4) ^ crc_table[(reg ^ (d >> 4)) & 0x000f];
119 *crc = reg;
122 /* ---- BCSP core ---- */
124 static void bcsp_slip_msgdelim(struct sk_buff *skb)
126 const char pkt_delim = 0xc0;
128 memcpy(skb_put(skb, 1), &pkt_delim, 1);
131 static void bcsp_slip_one_byte(struct sk_buff *skb, u8 c)
133 const char esc_c0[2] = { 0xdb, 0xdc };
134 const char esc_db[2] = { 0xdb, 0xdd };
136 switch (c) {
137 case 0xc0:
138 memcpy(skb_put(skb, 2), &esc_c0, 2);
139 break;
140 case 0xdb:
141 memcpy(skb_put(skb, 2), &esc_db, 2);
142 break;
143 default:
144 memcpy(skb_put(skb, 1), &c, 1);
148 static int bcsp_enqueue(struct hci_uart *hu, struct sk_buff *skb)
150 struct bcsp_struct *bcsp = hu->priv;
152 if (skb->len > 0xFFF) {
153 BT_ERR("Packet too long");
154 kfree_skb(skb);
155 return 0;
158 switch (hci_skb_pkt_type(skb)) {
159 case HCI_ACLDATA_PKT:
160 case HCI_COMMAND_PKT:
161 skb_queue_tail(&bcsp->rel, skb);
162 break;
164 case HCI_SCODATA_PKT:
165 skb_queue_tail(&bcsp->unrel, skb);
166 break;
168 default:
169 BT_ERR("Unknown packet type");
170 kfree_skb(skb);
171 break;
174 return 0;
177 static struct sk_buff *bcsp_prepare_pkt(struct bcsp_struct *bcsp, u8 *data,
178 int len, int pkt_type)
180 struct sk_buff *nskb;
181 u8 hdr[4], chan;
182 u16 BCSP_CRC_INIT(bcsp_txmsg_crc);
183 int rel, i;
185 switch (pkt_type) {
186 case HCI_ACLDATA_PKT:
187 chan = 6; /* BCSP ACL channel */
188 rel = 1; /* reliable channel */
189 break;
190 case HCI_COMMAND_PKT:
191 chan = 5; /* BCSP cmd/evt channel */
192 rel = 1; /* reliable channel */
193 break;
194 case HCI_SCODATA_PKT:
195 chan = 7; /* BCSP SCO channel */
196 rel = 0; /* unreliable channel */
197 break;
198 case BCSP_LE_PKT:
199 chan = 1; /* BCSP LE channel */
200 rel = 0; /* unreliable channel */
201 break;
202 case BCSP_ACK_PKT:
203 chan = 0; /* BCSP internal channel */
204 rel = 0; /* unreliable channel */
205 break;
206 default:
207 BT_ERR("Unknown packet type");
208 return NULL;
211 if (hciextn && chan == 5) {
212 __le16 opcode = ((struct hci_command_hdr *)data)->opcode;
214 /* Vendor specific commands */
215 if (hci_opcode_ogf(__le16_to_cpu(opcode)) == 0x3f) {
216 u8 desc = *(data + HCI_COMMAND_HDR_SIZE);
218 if ((desc & 0xf0) == 0xc0) {
219 data += HCI_COMMAND_HDR_SIZE + 1;
220 len -= HCI_COMMAND_HDR_SIZE + 1;
221 chan = desc & 0x0f;
226 /* Max len of packet: (original len +4(bcsp hdr) +2(crc))*2
227 * (because bytes 0xc0 and 0xdb are escaped, worst case is
228 * when the packet is all made of 0xc0 and 0xdb :) )
229 * + 2 (0xc0 delimiters at start and end).
232 nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);
233 if (!nskb)
234 return NULL;
236 hci_skb_pkt_type(nskb) = pkt_type;
238 bcsp_slip_msgdelim(nskb);
240 hdr[0] = bcsp->rxseq_txack << 3;
241 bcsp->txack_req = 0;
242 BT_DBG("We request packet no %u to card", bcsp->rxseq_txack);
244 if (rel) {
245 hdr[0] |= 0x80 + bcsp->msgq_txseq;
246 BT_DBG("Sending packet with seqno %u", bcsp->msgq_txseq);
247 bcsp->msgq_txseq = (bcsp->msgq_txseq + 1) & 0x07;
250 if (bcsp->use_crc)
251 hdr[0] |= 0x40;
253 hdr[1] = ((len << 4) & 0xff) | chan;
254 hdr[2] = len >> 4;
255 hdr[3] = ~(hdr[0] + hdr[1] + hdr[2]);
257 /* Put BCSP header */
258 for (i = 0; i < 4; i++) {
259 bcsp_slip_one_byte(nskb, hdr[i]);
261 if (bcsp->use_crc)
262 bcsp_crc_update(&bcsp_txmsg_crc, hdr[i]);
265 /* Put payload */
266 for (i = 0; i < len; i++) {
267 bcsp_slip_one_byte(nskb, data[i]);
269 if (bcsp->use_crc)
270 bcsp_crc_update(&bcsp_txmsg_crc, data[i]);
273 /* Put CRC */
274 if (bcsp->use_crc) {
275 bcsp_txmsg_crc = bitrev16(bcsp_txmsg_crc);
276 bcsp_slip_one_byte(nskb, (u8)((bcsp_txmsg_crc >> 8) & 0x00ff));
277 bcsp_slip_one_byte(nskb, (u8)(bcsp_txmsg_crc & 0x00ff));
280 bcsp_slip_msgdelim(nskb);
281 return nskb;
284 /* This is a rewrite of pkt_avail in ABCSP */
285 static struct sk_buff *bcsp_dequeue(struct hci_uart *hu)
287 struct bcsp_struct *bcsp = hu->priv;
288 unsigned long flags;
289 struct sk_buff *skb;
291 /* First of all, check for unreliable messages in the queue,
292 * since they have priority
295 skb = skb_dequeue(&bcsp->unrel);
296 if (skb != NULL) {
297 struct sk_buff *nskb;
299 nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len,
300 hci_skb_pkt_type(skb));
301 if (nskb) {
302 kfree_skb(skb);
303 return nskb;
304 } else {
305 skb_queue_head(&bcsp->unrel, skb);
306 BT_ERR("Could not dequeue pkt because alloc_skb failed");
310 /* Now, try to send a reliable pkt. We can only send a
311 * reliable packet if the number of packets sent but not yet ack'ed
312 * is < than the winsize
315 spin_lock_irqsave_nested(&bcsp->unack.lock, flags, SINGLE_DEPTH_NESTING);
317 if (bcsp->unack.qlen < BCSP_TXWINSIZE) {
318 skb = skb_dequeue(&bcsp->rel);
319 if (skb != NULL) {
320 struct sk_buff *nskb;
322 nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len,
323 hci_skb_pkt_type(skb));
324 if (nskb) {
325 __skb_queue_tail(&bcsp->unack, skb);
326 mod_timer(&bcsp->tbcsp, jiffies + HZ / 4);
327 spin_unlock_irqrestore(&bcsp->unack.lock, flags);
328 return nskb;
329 } else {
330 skb_queue_head(&bcsp->rel, skb);
331 BT_ERR("Could not dequeue pkt because alloc_skb failed");
336 spin_unlock_irqrestore(&bcsp->unack.lock, flags);
338 /* We could not send a reliable packet, either because there are
339 * none or because there are too many unack'ed pkts. Did we receive
340 * any packets we have not acknowledged yet ?
343 if (bcsp->txack_req) {
344 /* if so, craft an empty ACK pkt and send it on BCSP unreliable
345 * channel 0
347 struct sk_buff *nskb = bcsp_prepare_pkt(bcsp, NULL, 0, BCSP_ACK_PKT);
348 return nskb;
351 /* We have nothing to send */
352 return NULL;
355 static int bcsp_flush(struct hci_uart *hu)
357 BT_DBG("hu %p", hu);
358 return 0;
361 /* Remove ack'ed packets */
362 static void bcsp_pkt_cull(struct bcsp_struct *bcsp)
364 struct sk_buff *skb, *tmp;
365 unsigned long flags;
366 int i, pkts_to_be_removed;
367 u8 seqno;
369 spin_lock_irqsave(&bcsp->unack.lock, flags);
371 pkts_to_be_removed = skb_queue_len(&bcsp->unack);
372 seqno = bcsp->msgq_txseq;
374 while (pkts_to_be_removed) {
375 if (bcsp->rxack == seqno)
376 break;
377 pkts_to_be_removed--;
378 seqno = (seqno - 1) & 0x07;
381 if (bcsp->rxack != seqno)
382 BT_ERR("Peer acked invalid packet");
384 BT_DBG("Removing %u pkts out of %u, up to seqno %u",
385 pkts_to_be_removed, skb_queue_len(&bcsp->unack),
386 (seqno - 1) & 0x07);
388 i = 0;
389 skb_queue_walk_safe(&bcsp->unack, skb, tmp) {
390 if (i >= pkts_to_be_removed)
391 break;
392 i++;
394 __skb_unlink(skb, &bcsp->unack);
395 kfree_skb(skb);
398 if (skb_queue_empty(&bcsp->unack))
399 del_timer(&bcsp->tbcsp);
401 spin_unlock_irqrestore(&bcsp->unack.lock, flags);
403 if (i != pkts_to_be_removed)
404 BT_ERR("Removed only %u out of %u pkts", i, pkts_to_be_removed);
407 /* Handle BCSP link-establishment packets. When we
408 * detect a "sync" packet, symptom that the BT module has reset,
409 * we do nothing :) (yet)
411 static void bcsp_handle_le_pkt(struct hci_uart *hu)
413 struct bcsp_struct *bcsp = hu->priv;
414 u8 conf_pkt[4] = { 0xad, 0xef, 0xac, 0xed };
415 u8 conf_rsp_pkt[4] = { 0xde, 0xad, 0xd0, 0xd0 };
416 u8 sync_pkt[4] = { 0xda, 0xdc, 0xed, 0xed };
418 /* spot "conf" pkts and reply with a "conf rsp" pkt */
419 if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&
420 !memcmp(&bcsp->rx_skb->data[4], conf_pkt, 4)) {
421 struct sk_buff *nskb = alloc_skb(4, GFP_ATOMIC);
423 BT_DBG("Found a LE conf pkt");
424 if (!nskb)
425 return;
426 memcpy(skb_put(nskb, 4), conf_rsp_pkt, 4);
427 hci_skb_pkt_type(nskb) = BCSP_LE_PKT;
429 skb_queue_head(&bcsp->unrel, nskb);
430 hci_uart_tx_wakeup(hu);
432 /* Spot "sync" pkts. If we find one...disaster! */
433 else if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&
434 !memcmp(&bcsp->rx_skb->data[4], sync_pkt, 4)) {
435 BT_ERR("Found a LE sync pkt, card has reset");
439 static inline void bcsp_unslip_one_byte(struct bcsp_struct *bcsp, unsigned char byte)
441 const u8 c0 = 0xc0, db = 0xdb;
443 switch (bcsp->rx_esc_state) {
444 case BCSP_ESCSTATE_NOESC:
445 switch (byte) {
446 case 0xdb:
447 bcsp->rx_esc_state = BCSP_ESCSTATE_ESC;
448 break;
449 default:
450 memcpy(skb_put(bcsp->rx_skb, 1), &byte, 1);
451 if ((bcsp->rx_skb->data[0] & 0x40) != 0 &&
452 bcsp->rx_state != BCSP_W4_CRC)
453 bcsp_crc_update(&bcsp->message_crc, byte);
454 bcsp->rx_count--;
456 break;
458 case BCSP_ESCSTATE_ESC:
459 switch (byte) {
460 case 0xdc:
461 memcpy(skb_put(bcsp->rx_skb, 1), &c0, 1);
462 if ((bcsp->rx_skb->data[0] & 0x40) != 0 &&
463 bcsp->rx_state != BCSP_W4_CRC)
464 bcsp_crc_update(&bcsp->message_crc, 0xc0);
465 bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
466 bcsp->rx_count--;
467 break;
469 case 0xdd:
470 memcpy(skb_put(bcsp->rx_skb, 1), &db, 1);
471 if ((bcsp->rx_skb->data[0] & 0x40) != 0 &&
472 bcsp->rx_state != BCSP_W4_CRC)
473 bcsp_crc_update(&bcsp->message_crc, 0xdb);
474 bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
475 bcsp->rx_count--;
476 break;
478 default:
479 BT_ERR("Invalid byte %02x after esc byte", byte);
480 kfree_skb(bcsp->rx_skb);
481 bcsp->rx_skb = NULL;
482 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
483 bcsp->rx_count = 0;
488 static void bcsp_complete_rx_pkt(struct hci_uart *hu)
490 struct bcsp_struct *bcsp = hu->priv;
491 int pass_up = 0;
493 if (bcsp->rx_skb->data[0] & 0x80) { /* reliable pkt */
494 BT_DBG("Received seqno %u from card", bcsp->rxseq_txack);
496 /* check the rx sequence number is as expected */
497 if ((bcsp->rx_skb->data[0] & 0x07) == bcsp->rxseq_txack) {
498 bcsp->rxseq_txack++;
499 bcsp->rxseq_txack %= 0x8;
500 } else {
501 /* handle re-transmitted packet or
502 * when packet was missed
504 BT_ERR("Out-of-order packet arrived, got %u expected %u",
505 bcsp->rx_skb->data[0] & 0x07, bcsp->rxseq_txack);
507 /* do not process out-of-order packet payload */
508 pass_up = 2;
511 /* send current txack value to all received reliable packets */
512 bcsp->txack_req = 1;
514 /* If needed, transmit an ack pkt */
515 hci_uart_tx_wakeup(hu);
518 bcsp->rxack = (bcsp->rx_skb->data[0] >> 3) & 0x07;
519 BT_DBG("Request for pkt %u from card", bcsp->rxack);
521 /* handle received ACK indications,
522 * including those from out-of-order packets
524 bcsp_pkt_cull(bcsp);
526 if (pass_up != 2) {
527 if ((bcsp->rx_skb->data[1] & 0x0f) == 6 &&
528 (bcsp->rx_skb->data[0] & 0x80)) {
529 hci_skb_pkt_type(bcsp->rx_skb) = HCI_ACLDATA_PKT;
530 pass_up = 1;
531 } else if ((bcsp->rx_skb->data[1] & 0x0f) == 5 &&
532 (bcsp->rx_skb->data[0] & 0x80)) {
533 hci_skb_pkt_type(bcsp->rx_skb) = HCI_EVENT_PKT;
534 pass_up = 1;
535 } else if ((bcsp->rx_skb->data[1] & 0x0f) == 7) {
536 hci_skb_pkt_type(bcsp->rx_skb) = HCI_SCODATA_PKT;
537 pass_up = 1;
538 } else if ((bcsp->rx_skb->data[1] & 0x0f) == 1 &&
539 !(bcsp->rx_skb->data[0] & 0x80)) {
540 bcsp_handle_le_pkt(hu);
541 pass_up = 0;
542 } else {
543 pass_up = 0;
547 if (pass_up == 0) {
548 struct hci_event_hdr hdr;
549 u8 desc = (bcsp->rx_skb->data[1] & 0x0f);
551 if (desc != 0 && desc != 1) {
552 if (hciextn) {
553 desc |= 0xc0;
554 skb_pull(bcsp->rx_skb, 4);
555 memcpy(skb_push(bcsp->rx_skb, 1), &desc, 1);
557 hdr.evt = 0xff;
558 hdr.plen = bcsp->rx_skb->len;
559 memcpy(skb_push(bcsp->rx_skb, HCI_EVENT_HDR_SIZE), &hdr, HCI_EVENT_HDR_SIZE);
560 hci_skb_pkt_type(bcsp->rx_skb) = HCI_EVENT_PKT;
562 hci_recv_frame(hu->hdev, bcsp->rx_skb);
563 } else {
564 BT_ERR("Packet for unknown channel (%u %s)",
565 bcsp->rx_skb->data[1] & 0x0f,
566 bcsp->rx_skb->data[0] & 0x80 ?
567 "reliable" : "unreliable");
568 kfree_skb(bcsp->rx_skb);
570 } else
571 kfree_skb(bcsp->rx_skb);
572 } else if (pass_up == 1) {
573 /* Pull out BCSP hdr */
574 skb_pull(bcsp->rx_skb, 4);
576 hci_recv_frame(hu->hdev, bcsp->rx_skb);
577 } else {
578 /* ignore packet payload of already ACKed re-transmitted
579 * packets or when a packet was missed in the BCSP window
581 kfree_skb(bcsp->rx_skb);
584 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
585 bcsp->rx_skb = NULL;
588 static u16 bscp_get_crc(struct bcsp_struct *bcsp)
590 return get_unaligned_be16(&bcsp->rx_skb->data[bcsp->rx_skb->len - 2]);
593 /* Recv data */
594 static int bcsp_recv(struct hci_uart *hu, const void *data, int count)
596 struct bcsp_struct *bcsp = hu->priv;
597 const unsigned char *ptr;
599 BT_DBG("hu %p count %d rx_state %d rx_count %ld",
600 hu, count, bcsp->rx_state, bcsp->rx_count);
602 ptr = data;
603 while (count) {
604 if (bcsp->rx_count) {
605 if (*ptr == 0xc0) {
606 BT_ERR("Short BCSP packet");
607 kfree_skb(bcsp->rx_skb);
608 bcsp->rx_state = BCSP_W4_PKT_START;
609 bcsp->rx_count = 0;
610 } else
611 bcsp_unslip_one_byte(bcsp, *ptr);
613 ptr++; count--;
614 continue;
617 switch (bcsp->rx_state) {
618 case BCSP_W4_BCSP_HDR:
619 if ((0xff & (u8)~(bcsp->rx_skb->data[0] + bcsp->rx_skb->data[1] +
620 bcsp->rx_skb->data[2])) != bcsp->rx_skb->data[3]) {
621 BT_ERR("Error in BCSP hdr checksum");
622 kfree_skb(bcsp->rx_skb);
623 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
624 bcsp->rx_count = 0;
625 continue;
627 bcsp->rx_state = BCSP_W4_DATA;
628 bcsp->rx_count = (bcsp->rx_skb->data[1] >> 4) +
629 (bcsp->rx_skb->data[2] << 4); /* May be 0 */
630 continue;
632 case BCSP_W4_DATA:
633 if (bcsp->rx_skb->data[0] & 0x40) { /* pkt with crc */
634 bcsp->rx_state = BCSP_W4_CRC;
635 bcsp->rx_count = 2;
636 } else
637 bcsp_complete_rx_pkt(hu);
638 continue;
640 case BCSP_W4_CRC:
641 if (bitrev16(bcsp->message_crc) != bscp_get_crc(bcsp)) {
642 BT_ERR("Checksum failed: computed %04x received %04x",
643 bitrev16(bcsp->message_crc),
644 bscp_get_crc(bcsp));
646 kfree_skb(bcsp->rx_skb);
647 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
648 bcsp->rx_count = 0;
649 continue;
651 skb_trim(bcsp->rx_skb, bcsp->rx_skb->len - 2);
652 bcsp_complete_rx_pkt(hu);
653 continue;
655 case BCSP_W4_PKT_DELIMITER:
656 switch (*ptr) {
657 case 0xc0:
658 bcsp->rx_state = BCSP_W4_PKT_START;
659 break;
660 default:
661 /*BT_ERR("Ignoring byte %02x", *ptr);*/
662 break;
664 ptr++; count--;
665 break;
667 case BCSP_W4_PKT_START:
668 switch (*ptr) {
669 case 0xc0:
670 ptr++; count--;
671 break;
673 default:
674 bcsp->rx_state = BCSP_W4_BCSP_HDR;
675 bcsp->rx_count = 4;
676 bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
677 BCSP_CRC_INIT(bcsp->message_crc);
679 /* Do not increment ptr or decrement count
680 * Allocate packet. Max len of a BCSP pkt=
681 * 0xFFF (payload) +4 (header) +2 (crc)
684 bcsp->rx_skb = bt_skb_alloc(0x1005, GFP_ATOMIC);
685 if (!bcsp->rx_skb) {
686 BT_ERR("Can't allocate mem for new packet");
687 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
688 bcsp->rx_count = 0;
689 return 0;
691 break;
693 break;
696 return count;
699 /* Arrange to retransmit all messages in the relq. */
700 static void bcsp_timed_event(unsigned long arg)
702 struct hci_uart *hu = (struct hci_uart *)arg;
703 struct bcsp_struct *bcsp = hu->priv;
704 struct sk_buff *skb;
705 unsigned long flags;
707 BT_DBG("hu %p retransmitting %u pkts", hu, bcsp->unack.qlen);
709 spin_lock_irqsave_nested(&bcsp->unack.lock, flags, SINGLE_DEPTH_NESTING);
711 while ((skb = __skb_dequeue_tail(&bcsp->unack)) != NULL) {
712 bcsp->msgq_txseq = (bcsp->msgq_txseq - 1) & 0x07;
713 skb_queue_head(&bcsp->rel, skb);
716 spin_unlock_irqrestore(&bcsp->unack.lock, flags);
718 hci_uart_tx_wakeup(hu);
721 static int bcsp_open(struct hci_uart *hu)
723 struct bcsp_struct *bcsp;
725 BT_DBG("hu %p", hu);
727 bcsp = kzalloc(sizeof(*bcsp), GFP_KERNEL);
728 if (!bcsp)
729 return -ENOMEM;
731 hu->priv = bcsp;
732 skb_queue_head_init(&bcsp->unack);
733 skb_queue_head_init(&bcsp->rel);
734 skb_queue_head_init(&bcsp->unrel);
736 init_timer(&bcsp->tbcsp);
737 bcsp->tbcsp.function = bcsp_timed_event;
738 bcsp->tbcsp.data = (u_long)hu;
740 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
742 if (txcrc)
743 bcsp->use_crc = 1;
745 return 0;
748 static int bcsp_close(struct hci_uart *hu)
750 struct bcsp_struct *bcsp = hu->priv;
752 del_timer_sync(&bcsp->tbcsp);
754 hu->priv = NULL;
756 BT_DBG("hu %p", hu);
758 skb_queue_purge(&bcsp->unack);
759 skb_queue_purge(&bcsp->rel);
760 skb_queue_purge(&bcsp->unrel);
762 kfree(bcsp);
763 return 0;
766 static 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
777 int __init bcsp_init(void)
779 return hci_uart_register_proto(&bcsp);
782 int __exit bcsp_deinit(void)
784 return hci_uart_unregister_proto(&bcsp);
787 module_param(txcrc, bool, 0644);
788 MODULE_PARM_DESC(txcrc, "Transmit CRC with every BCSP packet");
790 module_param(hciextn, bool, 0644);
791 MODULE_PARM_DESC(hciextn, "Convert HCI Extensions into BCSP packets");