ia64/linux-2.6.18-xen.hg

view drivers/bluetooth/hci_bcsp.c @ 897:329ea0ccb344

balloon: try harder to balloon up under memory pressure.

Currently if the balloon driver is unable to increase the guest's
reservation it assumes the failure was due to reaching its full
allocation, gives up on the ballooning operation and records the limit
it reached as the "hard limit". The driver will not try again until
the target is set again (even to the same value).

However it is possible that ballooning has in fact failed due to
memory pressure in the host and therefore it is desirable to keep
attempting to reach the target in case memory becomes available. The
most likely scenario is that some guests are ballooning down while
others are ballooning up and therefore there is temporary memory
pressure while things stabilise. You would not expect a well behaved
toolstack to ask a domain to balloon to more than its allocation nor
would you expect it to deliberately over-commit memory by setting
balloon targets which exceed the total host memory.

This patch drops the concept of a hard limit and causes the balloon
driver to retry increasing the reservation on a timer in the same
manner as when decreasing the reservation.

Also if we partially succeed in increasing the reservation
(i.e. receive less pages than we asked for) then we may as well keep
those pages rather than returning them to Xen.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Fri Jun 05 14:01:20 2009 +0100 (2009-06-05)
parents 831230e53067
children
line source
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 */
25 #include <linux/module.h>
27 #include <linux/kernel.h>
28 #include <linux/init.h>
29 #include <linux/sched.h>
30 #include <linux/types.h>
31 #include <linux/fcntl.h>
32 #include <linux/interrupt.h>
33 #include <linux/ptrace.h>
34 #include <linux/poll.h>
36 #include <linux/slab.h>
37 #include <linux/tty.h>
38 #include <linux/errno.h>
39 #include <linux/string.h>
40 #include <linux/signal.h>
41 #include <linux/ioctl.h>
42 #include <linux/skbuff.h>
44 #include <net/bluetooth/bluetooth.h>
45 #include <net/bluetooth/hci_core.h>
47 #include "hci_uart.h"
49 #ifndef CONFIG_BT_HCIUART_DEBUG
50 #undef BT_DBG
51 #define BT_DBG( A... )
52 #endif
54 #define VERSION "0.3"
56 static int txcrc = 1;
57 static int hciextn = 1;
59 #define BCSP_TXWINSIZE 4
61 #define BCSP_ACK_PKT 0x05
62 #define BCSP_LE_PKT 0x06
64 struct bcsp_struct {
65 struct sk_buff_head unack; /* Unack'ed packets queue */
66 struct sk_buff_head rel; /* Reliable packets queue */
67 struct sk_buff_head unrel; /* Unreliable packets queue */
69 unsigned long rx_count;
70 struct sk_buff *rx_skb;
71 u8 rxseq_txack; /* rxseq == txack. */
72 u8 rxack; /* Last packet sent by us that the peer ack'ed */
73 struct timer_list tbcsp;
75 enum {
76 BCSP_W4_PKT_DELIMITER,
77 BCSP_W4_PKT_START,
78 BCSP_W4_BCSP_HDR,
79 BCSP_W4_DATA,
80 BCSP_W4_CRC
81 } rx_state;
83 enum {
84 BCSP_ESCSTATE_NOESC,
85 BCSP_ESCSTATE_ESC
86 } rx_esc_state;
88 u8 use_crc;
89 u16 message_crc;
90 u8 txack_req; /* Do we need to send ack's to the peer? */
92 /* Reliable packet sequence number - used to assign seq to each rel pkt. */
93 u8 msgq_txseq;
94 };
96 /* ---- BCSP CRC calculation ---- */
98 /* Table for calculating CRC for polynomial 0x1021, LSB processed first,
99 initial value 0xffff, bits shifted in reverse order. */
101 static const u16 crc_table[] = {
102 0x0000, 0x1081, 0x2102, 0x3183,
103 0x4204, 0x5285, 0x6306, 0x7387,
104 0x8408, 0x9489, 0xa50a, 0xb58b,
105 0xc60c, 0xd68d, 0xe70e, 0xf78f
106 };
108 /* Initialise the crc calculator */
109 #define BCSP_CRC_INIT(x) x = 0xffff
111 /*
112 Update crc with next data byte
114 Implementation note
115 The data byte is treated as two nibbles. The crc is generated
116 in reverse, i.e., bits are fed into the register from the top.
117 */
118 static void bcsp_crc_update(u16 *crc, u8 d)
119 {
120 u16 reg = *crc;
122 reg = (reg >> 4) ^ crc_table[(reg ^ d) & 0x000f];
123 reg = (reg >> 4) ^ crc_table[(reg ^ (d >> 4)) & 0x000f];
125 *crc = reg;
126 }
128 /*
129 Get reverse of generated crc
131 Implementation note
132 The crc generator (bcsp_crc_init() and bcsp_crc_update())
133 creates a reversed crc, so it needs to be swapped back before
134 being passed on.
135 */
136 static u16 bcsp_crc_reverse(u16 crc)
137 {
138 u16 b, rev;
140 for (b = 0, rev = 0; b < 16; b++) {
141 rev = rev << 1;
142 rev |= (crc & 1);
143 crc = crc >> 1;
144 }
146 return (rev);
147 }
149 /* ---- BCSP core ---- */
151 static void bcsp_slip_msgdelim(struct sk_buff *skb)
152 {
153 const char pkt_delim = 0xc0;
155 memcpy(skb_put(skb, 1), &pkt_delim, 1);
156 }
158 static void bcsp_slip_one_byte(struct sk_buff *skb, u8 c)
159 {
160 const char esc_c0[2] = { 0xdb, 0xdc };
161 const char esc_db[2] = { 0xdb, 0xdd };
163 switch (c) {
164 case 0xc0:
165 memcpy(skb_put(skb, 2), &esc_c0, 2);
166 break;
167 case 0xdb:
168 memcpy(skb_put(skb, 2), &esc_db, 2);
169 break;
170 default:
171 memcpy(skb_put(skb, 1), &c, 1);
172 }
173 }
175 static int bcsp_enqueue(struct hci_uart *hu, struct sk_buff *skb)
176 {
177 struct bcsp_struct *bcsp = hu->priv;
179 if (skb->len > 0xFFF) {
180 BT_ERR("Packet too long");
181 kfree_skb(skb);
182 return 0;
183 }
185 switch (bt_cb(skb)->pkt_type) {
186 case HCI_ACLDATA_PKT:
187 case HCI_COMMAND_PKT:
188 skb_queue_tail(&bcsp->rel, skb);
189 break;
191 case HCI_SCODATA_PKT:
192 skb_queue_tail(&bcsp->unrel, skb);
193 break;
195 default:
196 BT_ERR("Unknown packet type");
197 kfree_skb(skb);
198 break;
199 }
201 return 0;
202 }
204 static struct sk_buff *bcsp_prepare_pkt(struct bcsp_struct *bcsp, u8 *data,
205 int len, int pkt_type)
206 {
207 struct sk_buff *nskb;
208 u8 hdr[4], chan;
209 u16 BCSP_CRC_INIT(bcsp_txmsg_crc);
210 int rel, i;
212 switch (pkt_type) {
213 case HCI_ACLDATA_PKT:
214 chan = 6; /* BCSP ACL channel */
215 rel = 1; /* reliable channel */
216 break;
217 case HCI_COMMAND_PKT:
218 chan = 5; /* BCSP cmd/evt channel */
219 rel = 1; /* reliable channel */
220 break;
221 case HCI_SCODATA_PKT:
222 chan = 7; /* BCSP SCO channel */
223 rel = 0; /* unreliable channel */
224 break;
225 case BCSP_LE_PKT:
226 chan = 1; /* BCSP LE channel */
227 rel = 0; /* unreliable channel */
228 break;
229 case BCSP_ACK_PKT:
230 chan = 0; /* BCSP internal channel */
231 rel = 0; /* unreliable channel */
232 break;
233 default:
234 BT_ERR("Unknown packet type");
235 return NULL;
236 }
238 if (hciextn && chan == 5) {
239 struct hci_command_hdr *hdr = (struct hci_command_hdr *) data;
241 if (hci_opcode_ogf(__le16_to_cpu(hdr->opcode)) == OGF_VENDOR_CMD) {
242 u8 desc = *(data + HCI_COMMAND_HDR_SIZE);
243 if ((desc & 0xf0) == 0xc0) {
244 data += HCI_COMMAND_HDR_SIZE + 1;
245 len -= HCI_COMMAND_HDR_SIZE + 1;
246 chan = desc & 0x0f;
247 }
248 }
249 }
251 /* Max len of packet: (original len +4(bcsp hdr) +2(crc))*2
252 (because bytes 0xc0 and 0xdb are escaped, worst case is
253 when the packet is all made of 0xc0 and 0xdb :) )
254 + 2 (0xc0 delimiters at start and end). */
256 nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);
257 if (!nskb)
258 return NULL;
260 bt_cb(nskb)->pkt_type = pkt_type;
262 bcsp_slip_msgdelim(nskb);
264 hdr[0] = bcsp->rxseq_txack << 3;
265 bcsp->txack_req = 0;
266 BT_DBG("We request packet no %u to card", bcsp->rxseq_txack);
268 if (rel) {
269 hdr[0] |= 0x80 + bcsp->msgq_txseq;
270 BT_DBG("Sending packet with seqno %u", bcsp->msgq_txseq);
271 bcsp->msgq_txseq = ++(bcsp->msgq_txseq) & 0x07;
272 }
274 if (bcsp->use_crc)
275 hdr[0] |= 0x40;
277 hdr[1] = ((len << 4) & 0xff) | chan;
278 hdr[2] = len >> 4;
279 hdr[3] = ~(hdr[0] + hdr[1] + hdr[2]);
281 /* Put BCSP header */
282 for (i = 0; i < 4; i++) {
283 bcsp_slip_one_byte(nskb, hdr[i]);
285 if (bcsp->use_crc)
286 bcsp_crc_update(&bcsp_txmsg_crc, hdr[i]);
287 }
289 /* Put payload */
290 for (i = 0; i < len; i++) {
291 bcsp_slip_one_byte(nskb, data[i]);
293 if (bcsp->use_crc)
294 bcsp_crc_update(&bcsp_txmsg_crc, data[i]);
295 }
297 /* Put CRC */
298 if (bcsp->use_crc) {
299 bcsp_txmsg_crc = bcsp_crc_reverse(bcsp_txmsg_crc);
300 bcsp_slip_one_byte(nskb, (u8) ((bcsp_txmsg_crc >> 8) & 0x00ff));
301 bcsp_slip_one_byte(nskb, (u8) (bcsp_txmsg_crc & 0x00ff));
302 }
304 bcsp_slip_msgdelim(nskb);
305 return nskb;
306 }
308 /* This is a rewrite of pkt_avail in ABCSP */
309 static struct sk_buff *bcsp_dequeue(struct hci_uart *hu)
310 {
311 struct bcsp_struct *bcsp = hu->priv;
312 unsigned long flags;
313 struct sk_buff *skb;
315 /* First of all, check for unreliable messages in the queue,
316 since they have priority */
318 if ((skb = skb_dequeue(&bcsp->unrel)) != NULL) {
319 struct sk_buff *nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len, bt_cb(skb)->pkt_type);
320 if (nskb) {
321 kfree_skb(skb);
322 return nskb;
323 } else {
324 skb_queue_head(&bcsp->unrel, skb);
325 BT_ERR("Could not dequeue pkt because alloc_skb failed");
326 }
327 }
329 /* Now, try to send a reliable pkt. We can only send a
330 reliable packet if the number of packets sent but not yet ack'ed
331 is < than the winsize */
333 spin_lock_irqsave(&bcsp->unack.lock, flags);
335 if (bcsp->unack.qlen < BCSP_TXWINSIZE && (skb = skb_dequeue(&bcsp->rel)) != NULL) {
336 struct sk_buff *nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len, bt_cb(skb)->pkt_type);
337 if (nskb) {
338 __skb_queue_tail(&bcsp->unack, skb);
339 mod_timer(&bcsp->tbcsp, jiffies + HZ / 4);
340 spin_unlock_irqrestore(&bcsp->unack.lock, flags);
341 return nskb;
342 } else {
343 skb_queue_head(&bcsp->rel, skb);
344 BT_ERR("Could not dequeue pkt because alloc_skb failed");
345 }
346 }
348 spin_unlock_irqrestore(&bcsp->unack.lock, flags);
350 /* We could not send a reliable packet, either because there are
351 none or because there are too many unack'ed pkts. Did we receive
352 any packets we have not acknowledged yet ? */
354 if (bcsp->txack_req) {
355 /* if so, craft an empty ACK pkt and send it on BCSP unreliable
356 channel 0 */
357 struct sk_buff *nskb = bcsp_prepare_pkt(bcsp, NULL, 0, BCSP_ACK_PKT);
358 return nskb;
359 }
361 /* We have nothing to send */
362 return NULL;
363 }
365 static int bcsp_flush(struct hci_uart *hu)
366 {
367 BT_DBG("hu %p", hu);
368 return 0;
369 }
371 /* Remove ack'ed packets */
372 static void bcsp_pkt_cull(struct bcsp_struct *bcsp)
373 {
374 unsigned long flags;
375 struct sk_buff *skb;
376 int i, pkts_to_be_removed;
377 u8 seqno;
379 spin_lock_irqsave(&bcsp->unack.lock, flags);
381 pkts_to_be_removed = bcsp->unack.qlen;
382 seqno = bcsp->msgq_txseq;
384 while (pkts_to_be_removed) {
385 if (bcsp->rxack == seqno)
386 break;
387 pkts_to_be_removed--;
388 seqno = (seqno - 1) & 0x07;
389 }
391 if (bcsp->rxack != seqno)
392 BT_ERR("Peer acked invalid packet");
394 BT_DBG("Removing %u pkts out of %u, up to seqno %u",
395 pkts_to_be_removed, bcsp->unack.qlen, (seqno - 1) & 0x07);
397 for (i = 0, skb = ((struct sk_buff *) &bcsp->unack)->next; i < pkts_to_be_removed
398 && skb != (struct sk_buff *) &bcsp->unack; i++) {
399 struct sk_buff *nskb;
401 nskb = skb->next;
402 __skb_unlink(skb, &bcsp->unack);
403 kfree_skb(skb);
404 skb = nskb;
405 }
407 if (bcsp->unack.qlen == 0)
408 del_timer(&bcsp->tbcsp);
410 spin_unlock_irqrestore(&bcsp->unack.lock, flags);
412 if (i != pkts_to_be_removed)
413 BT_ERR("Removed only %u out of %u pkts", i, pkts_to_be_removed);
414 }
416 /* Handle BCSP link-establishment packets. When we
417 detect a "sync" packet, symptom that the BT module has reset,
418 we do nothing :) (yet) */
419 static void bcsp_handle_le_pkt(struct hci_uart *hu)
420 {
421 struct bcsp_struct *bcsp = hu->priv;
422 u8 conf_pkt[4] = { 0xad, 0xef, 0xac, 0xed };
423 u8 conf_rsp_pkt[4] = { 0xde, 0xad, 0xd0, 0xd0 };
424 u8 sync_pkt[4] = { 0xda, 0xdc, 0xed, 0xed };
426 /* spot "conf" pkts and reply with a "conf rsp" pkt */
427 if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&
428 !memcmp(&bcsp->rx_skb->data[4], conf_pkt, 4)) {
429 struct sk_buff *nskb = alloc_skb(4, GFP_ATOMIC);
431 BT_DBG("Found a LE conf pkt");
432 if (!nskb)
433 return;
434 memcpy(skb_put(nskb, 4), conf_rsp_pkt, 4);
435 bt_cb(nskb)->pkt_type = BCSP_LE_PKT;
437 skb_queue_head(&bcsp->unrel, nskb);
438 hci_uart_tx_wakeup(hu);
439 }
440 /* Spot "sync" pkts. If we find one...disaster! */
441 else if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&
442 !memcmp(&bcsp->rx_skb->data[4], sync_pkt, 4)) {
443 BT_ERR("Found a LE sync pkt, card has reset");
444 }
445 }
447 static inline void bcsp_unslip_one_byte(struct bcsp_struct *bcsp, unsigned char byte)
448 {
449 const u8 c0 = 0xc0, db = 0xdb;
451 switch (bcsp->rx_esc_state) {
452 case BCSP_ESCSTATE_NOESC:
453 switch (byte) {
454 case 0xdb:
455 bcsp->rx_esc_state = BCSP_ESCSTATE_ESC;
456 break;
457 default:
458 memcpy(skb_put(bcsp->rx_skb, 1), &byte, 1);
459 if ((bcsp->rx_skb-> data[0] & 0x40) != 0 &&
460 bcsp->rx_state != BCSP_W4_CRC)
461 bcsp_crc_update(&bcsp->message_crc, byte);
462 bcsp->rx_count--;
463 }
464 break;
466 case BCSP_ESCSTATE_ESC:
467 switch (byte) {
468 case 0xdc:
469 memcpy(skb_put(bcsp->rx_skb, 1), &c0, 1);
470 if ((bcsp->rx_skb-> data[0] & 0x40) != 0 &&
471 bcsp->rx_state != BCSP_W4_CRC)
472 bcsp_crc_update(&bcsp-> message_crc, 0xc0);
473 bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
474 bcsp->rx_count--;
475 break;
477 case 0xdd:
478 memcpy(skb_put(bcsp->rx_skb, 1), &db, 1);
479 if ((bcsp->rx_skb-> data[0] & 0x40) != 0 &&
480 bcsp->rx_state != BCSP_W4_CRC)
481 bcsp_crc_update(&bcsp-> message_crc, 0xdb);
482 bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
483 bcsp->rx_count--;
484 break;
486 default:
487 BT_ERR ("Invalid byte %02x after esc byte", byte);
488 kfree_skb(bcsp->rx_skb);
489 bcsp->rx_skb = NULL;
490 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
491 bcsp->rx_count = 0;
492 }
493 }
494 }
496 static void bcsp_complete_rx_pkt(struct hci_uart *hu)
497 {
498 struct bcsp_struct *bcsp = hu->priv;
499 int pass_up;
501 if (bcsp->rx_skb->data[0] & 0x80) { /* reliable pkt */
502 BT_DBG("Received seqno %u from card", bcsp->rxseq_txack);
503 bcsp->rxseq_txack++;
504 bcsp->rxseq_txack %= 0x8;
505 bcsp->txack_req = 1;
507 /* If needed, transmit an ack pkt */
508 hci_uart_tx_wakeup(hu);
509 }
511 bcsp->rxack = (bcsp->rx_skb->data[0] >> 3) & 0x07;
512 BT_DBG("Request for pkt %u from card", bcsp->rxack);
514 bcsp_pkt_cull(bcsp);
515 if ((bcsp->rx_skb->data[1] & 0x0f) == 6 &&
516 bcsp->rx_skb->data[0] & 0x80) {
517 bt_cb(bcsp->rx_skb)->pkt_type = HCI_ACLDATA_PKT;
518 pass_up = 1;
519 } else if ((bcsp->rx_skb->data[1] & 0x0f) == 5 &&
520 bcsp->rx_skb->data[0] & 0x80) {
521 bt_cb(bcsp->rx_skb)->pkt_type = HCI_EVENT_PKT;
522 pass_up = 1;
523 } else if ((bcsp->rx_skb->data[1] & 0x0f) == 7) {
524 bt_cb(bcsp->rx_skb)->pkt_type = HCI_SCODATA_PKT;
525 pass_up = 1;
526 } else if ((bcsp->rx_skb->data[1] & 0x0f) == 1 &&
527 !(bcsp->rx_skb->data[0] & 0x80)) {
528 bcsp_handle_le_pkt(hu);
529 pass_up = 0;
530 } else
531 pass_up = 0;
533 if (!pass_up) {
534 struct hci_event_hdr hdr;
535 u8 desc = (bcsp->rx_skb->data[1] & 0x0f);
537 if (desc != 0 && desc != 1) {
538 if (hciextn) {
539 desc |= 0xc0;
540 skb_pull(bcsp->rx_skb, 4);
541 memcpy(skb_push(bcsp->rx_skb, 1), &desc, 1);
543 hdr.evt = 0xff;
544 hdr.plen = bcsp->rx_skb->len;
545 memcpy(skb_push(bcsp->rx_skb, HCI_EVENT_HDR_SIZE), &hdr, HCI_EVENT_HDR_SIZE);
546 bt_cb(bcsp->rx_skb)->pkt_type = HCI_EVENT_PKT;
548 hci_recv_frame(bcsp->rx_skb);
549 } else {
550 BT_ERR ("Packet for unknown channel (%u %s)",
551 bcsp->rx_skb->data[1] & 0x0f,
552 bcsp->rx_skb->data[0] & 0x80 ?
553 "reliable" : "unreliable");
554 kfree_skb(bcsp->rx_skb);
555 }
556 } else
557 kfree_skb(bcsp->rx_skb);
558 } else {
559 /* Pull out BCSP hdr */
560 skb_pull(bcsp->rx_skb, 4);
562 hci_recv_frame(bcsp->rx_skb);
563 }
565 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
566 bcsp->rx_skb = NULL;
567 }
569 /* Recv data */
570 static int bcsp_recv(struct hci_uart *hu, void *data, int count)
571 {
572 struct bcsp_struct *bcsp = hu->priv;
573 register unsigned char *ptr;
575 BT_DBG("hu %p count %d rx_state %d rx_count %ld",
576 hu, count, bcsp->rx_state, bcsp->rx_count);
578 ptr = data;
579 while (count) {
580 if (bcsp->rx_count) {
581 if (*ptr == 0xc0) {
582 BT_ERR("Short BCSP packet");
583 kfree_skb(bcsp->rx_skb);
584 bcsp->rx_state = BCSP_W4_PKT_START;
585 bcsp->rx_count = 0;
586 } else
587 bcsp_unslip_one_byte(bcsp, *ptr);
589 ptr++; count--;
590 continue;
591 }
593 switch (bcsp->rx_state) {
594 case BCSP_W4_BCSP_HDR:
595 if ((0xff & (u8) ~ (bcsp->rx_skb->data[0] + bcsp->rx_skb->data[1] +
596 bcsp->rx_skb->data[2])) != bcsp->rx_skb->data[3]) {
597 BT_ERR("Error in BCSP hdr checksum");
598 kfree_skb(bcsp->rx_skb);
599 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
600 bcsp->rx_count = 0;
601 continue;
602 }
603 if (bcsp->rx_skb->data[0] & 0x80 /* reliable pkt */
604 && (bcsp->rx_skb->data[0] & 0x07) != bcsp->rxseq_txack) {
605 BT_ERR ("Out-of-order packet arrived, got %u expected %u",
606 bcsp->rx_skb->data[0] & 0x07, bcsp->rxseq_txack);
608 kfree_skb(bcsp->rx_skb);
609 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
610 bcsp->rx_count = 0;
611 continue;
612 }
613 bcsp->rx_state = BCSP_W4_DATA;
614 bcsp->rx_count = (bcsp->rx_skb->data[1] >> 4) +
615 (bcsp->rx_skb->data[2] << 4); /* May be 0 */
616 continue;
618 case BCSP_W4_DATA:
619 if (bcsp->rx_skb->data[0] & 0x40) { /* pkt with crc */
620 bcsp->rx_state = BCSP_W4_CRC;
621 bcsp->rx_count = 2;
622 } else
623 bcsp_complete_rx_pkt(hu);
624 continue;
626 case BCSP_W4_CRC:
627 if (bcsp_crc_reverse(bcsp->message_crc) !=
628 (bcsp->rx_skb->data[bcsp->rx_skb->len - 2] << 8) +
629 bcsp->rx_skb->data[bcsp->rx_skb->len - 1]) {
631 BT_ERR ("Checksum failed: computed %04x received %04x",
632 bcsp_crc_reverse(bcsp->message_crc),
633 (bcsp->rx_skb-> data[bcsp->rx_skb->len - 2] << 8) +
634 bcsp->rx_skb->data[bcsp->rx_skb->len - 1]);
636 kfree_skb(bcsp->rx_skb);
637 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
638 bcsp->rx_count = 0;
639 continue;
640 }
641 skb_trim(bcsp->rx_skb, bcsp->rx_skb->len - 2);
642 bcsp_complete_rx_pkt(hu);
643 continue;
645 case BCSP_W4_PKT_DELIMITER:
646 switch (*ptr) {
647 case 0xc0:
648 bcsp->rx_state = BCSP_W4_PKT_START;
649 break;
650 default:
651 /*BT_ERR("Ignoring byte %02x", *ptr);*/
652 break;
653 }
654 ptr++; count--;
655 break;
657 case BCSP_W4_PKT_START:
658 switch (*ptr) {
659 case 0xc0:
660 ptr++; count--;
661 break;
663 default:
664 bcsp->rx_state = BCSP_W4_BCSP_HDR;
665 bcsp->rx_count = 4;
666 bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
667 BCSP_CRC_INIT(bcsp->message_crc);
669 /* Do not increment ptr or decrement count
670 * Allocate packet. Max len of a BCSP pkt=
671 * 0xFFF (payload) +4 (header) +2 (crc) */
673 bcsp->rx_skb = bt_skb_alloc(0x1005, GFP_ATOMIC);
674 if (!bcsp->rx_skb) {
675 BT_ERR("Can't allocate mem for new packet");
676 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
677 bcsp->rx_count = 0;
678 return 0;
679 }
680 bcsp->rx_skb->dev = (void *) hu->hdev;
681 break;
682 }
683 break;
684 }
685 }
686 return count;
687 }
689 /* Arrange to retransmit all messages in the relq. */
690 static void bcsp_timed_event(unsigned long arg)
691 {
692 struct hci_uart *hu = (struct hci_uart *) arg;
693 struct bcsp_struct *bcsp = hu->priv;
694 struct sk_buff *skb;
695 unsigned long flags;
697 BT_DBG("hu %p retransmitting %u pkts", hu, bcsp->unack.qlen);
699 spin_lock_irqsave(&bcsp->unack.lock, flags);
701 while ((skb = __skb_dequeue_tail(&bcsp->unack)) != NULL) {
702 bcsp->msgq_txseq = (bcsp->msgq_txseq - 1) & 0x07;
703 skb_queue_head(&bcsp->rel, skb);
704 }
706 spin_unlock_irqrestore(&bcsp->unack.lock, flags);
708 hci_uart_tx_wakeup(hu);
709 }
711 static int bcsp_open(struct hci_uart *hu)
712 {
713 struct bcsp_struct *bcsp;
715 BT_DBG("hu %p", hu);
717 bcsp = kzalloc(sizeof(*bcsp), GFP_ATOMIC);
718 if (!bcsp)
719 return -ENOMEM;
721 hu->priv = bcsp;
722 skb_queue_head_init(&bcsp->unack);
723 skb_queue_head_init(&bcsp->rel);
724 skb_queue_head_init(&bcsp->unrel);
726 init_timer(&bcsp->tbcsp);
727 bcsp->tbcsp.function = bcsp_timed_event;
728 bcsp->tbcsp.data = (u_long) hu;
730 bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
732 if (txcrc)
733 bcsp->use_crc = 1;
735 return 0;
736 }
738 static int bcsp_close(struct hci_uart *hu)
739 {
740 struct bcsp_struct *bcsp = hu->priv;
741 hu->priv = NULL;
743 BT_DBG("hu %p", hu);
745 skb_queue_purge(&bcsp->unack);
746 skb_queue_purge(&bcsp->rel);
747 skb_queue_purge(&bcsp->unrel);
748 del_timer(&bcsp->tbcsp);
750 kfree(bcsp);
751 return 0;
752 }
754 static struct hci_uart_proto bcsp = {
755 .id = HCI_UART_BCSP,
756 .open = bcsp_open,
757 .close = bcsp_close,
758 .enqueue = bcsp_enqueue,
759 .dequeue = bcsp_dequeue,
760 .recv = bcsp_recv,
761 .flush = bcsp_flush
762 };
764 int bcsp_init(void)
765 {
766 int err = hci_uart_register_proto(&bcsp);
768 if (!err)
769 BT_INFO("HCI BCSP protocol initialized");
770 else
771 BT_ERR("HCI BCSP protocol registration failed");
773 return err;
774 }
776 int bcsp_deinit(void)
777 {
778 return hci_uart_unregister_proto(&bcsp);
779 }
781 module_param(txcrc, bool, 0644);
782 MODULE_PARM_DESC(txcrc, "Transmit CRC with every BCSP packet");
784 module_param(hciextn, bool, 0644);
785 MODULE_PARM_DESC(hciextn, "Convert HCI Extensions into BCSP packets");