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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
50#define VERSION "0.3"
51
52static bool txcrc = 1;
53static bool hciextn = 1;
54
55#define BCSP_TXWINSIZE	4
56
57#define BCSP_ACK_PKT	0x05
58#define BCSP_LE_PKT	0x06
59
60struct bcsp_struct {
61	struct sk_buff_head unack;	/* Unack'ed packets queue */
62	struct sk_buff_head rel;	/* Reliable packets queue */
63	struct sk_buff_head unrel;	/* Unreliable packets queue */
64
65	unsigned long rx_count;
66	struct	sk_buff *rx_skb;
67	u8	rxseq_txack;		/* rxseq == txack. */
68	u8	rxack;			/* Last packet sent by us that the peer ack'ed */
69	struct	timer_list tbcsp;
70
71	enum {
72		BCSP_W4_PKT_DELIMITER,
73		BCSP_W4_PKT_START,
74		BCSP_W4_BCSP_HDR,
75		BCSP_W4_DATA,
76		BCSP_W4_CRC
77	} rx_state;
78
79	enum {
80		BCSP_ESCSTATE_NOESC,
81		BCSP_ESCSTATE_ESC
82	} rx_esc_state;
83
84	u8	use_crc;
85	u16	message_crc;
86	u8	txack_req;		/* Do we need to send ack's to the peer? */
87
88	/* Reliable packet sequence number - used to assign seq to each rel pkt. */
89	u8	msgq_txseq;
90};
91
92/* ---- BCSP CRC calculation ---- */
93
94/* Table for calculating CRC for polynomial 0x1021, LSB processed first,
95initial value 0xffff, bits shifted in reverse order. */
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/*
108   Update crc with next data byte
109
110   Implementation note
111        The data byte is treated as two nibbles.  The crc is generated
112        in reverse, i.e., bits are fed into the register from the top.
113*/
114static void bcsp_crc_update(u16 *crc, u8 d)
115{
116	u16 reg = *crc;
117
118	reg = (reg >> 4) ^ crc_table[(reg ^ d) & 0x000f];
119	reg = (reg >> 4) ^ crc_table[(reg ^ (d >> 4)) & 0x000f];
120
121	*crc = reg;
122}
123
124/* ---- BCSP core ---- */
125
126static void bcsp_slip_msgdelim(struct sk_buff *skb)
127{
128	const char pkt_delim = 0xc0;
129
130	memcpy(skb_put(skb, 1), &pkt_delim, 1);
131}
132
133static void bcsp_slip_one_byte(struct sk_buff *skb, u8 c)
134{
135	const char esc_c0[2] = { 0xdb, 0xdc };
136	const char esc_db[2] = { 0xdb, 0xdd };
137
138	switch (c) {
139	case 0xc0:
140		memcpy(skb_put(skb, 2), &esc_c0, 2);
141		break;
142	case 0xdb:
143		memcpy(skb_put(skb, 2), &esc_db, 2);
144		break;
145	default:
146		memcpy(skb_put(skb, 1), &c, 1);
147	}
148}
149
150static int bcsp_enqueue(struct hci_uart *hu, struct sk_buff *skb)
151{
152	struct bcsp_struct *bcsp = hu->priv;
153
154	if (skb->len > 0xFFF) {
155		BT_ERR("Packet too long");
156		kfree_skb(skb);
157		return 0;
158	}
159
160	switch (bt_cb(skb)->pkt_type) {
161	case HCI_ACLDATA_PKT:
162	case HCI_COMMAND_PKT:
163		skb_queue_tail(&bcsp->rel, skb);
164		break;
165
166	case HCI_SCODATA_PKT:
167		skb_queue_tail(&bcsp->unrel, skb);
168		break;
169
170	default:
171		BT_ERR("Unknown packet type");
172		kfree_skb(skb);
173		break;
174	}
175
176	return 0;
177}
178
179static struct sk_buff *bcsp_prepare_pkt(struct bcsp_struct *bcsp, u8 *data,
180		int len, int pkt_type)
181{
182	struct sk_buff *nskb;
183	u8 hdr[4], chan;
184	u16 BCSP_CRC_INIT(bcsp_txmsg_crc);
185	int rel, i;
186
187	switch (pkt_type) {
188	case HCI_ACLDATA_PKT:
189		chan = 6;	/* BCSP ACL channel */
190		rel = 1;	/* reliable channel */
191		break;
192	case HCI_COMMAND_PKT:
193		chan = 5;	/* BCSP cmd/evt channel */
194		rel = 1;	/* reliable channel */
195		break;
196	case HCI_SCODATA_PKT:
197		chan = 7;	/* BCSP SCO channel */
198		rel = 0;	/* unreliable channel */
199		break;
200	case BCSP_LE_PKT:
201		chan = 1;	/* BCSP LE channel */
202		rel = 0;	/* unreliable channel */
203		break;
204	case BCSP_ACK_PKT:
205		chan = 0;	/* BCSP internal channel */
206		rel = 0;	/* unreliable channel */
207		break;
208	default:
209		BT_ERR("Unknown packet type");
210		return NULL;
211	}
212
213	if (hciextn && chan == 5) {
214		__le16 opcode = ((struct hci_command_hdr *)data)->opcode;
215
216		/* Vendor specific commands */
217		if (hci_opcode_ogf(__le16_to_cpu(opcode)) == 0x3f) {
218			u8 desc = *(data + HCI_COMMAND_HDR_SIZE);
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	nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);
233	if (!nskb)
234		return NULL;
235
236	bt_cb(nskb)->pkt_type = pkt_type;
237
238	bcsp_slip_msgdelim(nskb);
239
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);
243
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;
248	}
249
250	if (bcsp->use_crc)
251		hdr[0] |= 0x40;
252
253	hdr[1] = ((len << 4) & 0xff) | chan;
254	hdr[2] = len >> 4;
255	hdr[3] = ~(hdr[0] + hdr[1] + hdr[2]);
256
257	/* Put BCSP header */
258	for (i = 0; i < 4; i++) {
259		bcsp_slip_one_byte(nskb, hdr[i]);
260
261		if (bcsp->use_crc)
262			bcsp_crc_update(&bcsp_txmsg_crc, hdr[i]);
263	}
264
265	/* Put payload */
266	for (i = 0; i < len; i++) {
267		bcsp_slip_one_byte(nskb, data[i]);
268
269		if (bcsp->use_crc)
270			bcsp_crc_update(&bcsp_txmsg_crc, data[i]);
271	}
272
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));
278	}
279
280	bcsp_slip_msgdelim(nskb);
281	return nskb;
282}
283
284/* This is a rewrite of pkt_avail in ABCSP */
285static struct sk_buff *bcsp_dequeue(struct hci_uart *hu)
286{
287	struct bcsp_struct *bcsp = hu->priv;
288	unsigned long flags;
289	struct sk_buff *skb;
290
291	/* First of all, check for unreliable messages in the queue,
292	   since they have priority */
293
294	skb = skb_dequeue(&bcsp->unrel);
295	if (skb != NULL) {
296		struct sk_buff *nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len, bt_cb(skb)->pkt_type);
297		if (nskb) {
298			kfree_skb(skb);
299			return nskb;
300		} else {
301			skb_queue_head(&bcsp->unrel, skb);
302			BT_ERR("Could not dequeue pkt because alloc_skb failed");
303		}
304	}
305
306	/* Now, try to send a reliable pkt. We can only send a
307	   reliable packet if the number of packets sent but not yet ack'ed
308	   is < than the winsize */
309
310	spin_lock_irqsave_nested(&bcsp->unack.lock, flags, SINGLE_DEPTH_NESTING);
311
312	if (bcsp->unack.qlen < BCSP_TXWINSIZE) {
313		skb = skb_dequeue(&bcsp->rel);
314		if (skb != NULL) {
315			struct sk_buff *nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len,
316								bt_cb(skb)->pkt_type);
317			if (nskb) {
318				__skb_queue_tail(&bcsp->unack, skb);
319				mod_timer(&bcsp->tbcsp, jiffies + HZ / 4);
320				spin_unlock_irqrestore(&bcsp->unack.lock, flags);
321				return nskb;
322			} else {
323				skb_queue_head(&bcsp->rel, skb);
324				BT_ERR("Could not dequeue pkt because alloc_skb failed");
325			}
326		}
327	}
328
329	spin_unlock_irqrestore(&bcsp->unack.lock, flags);
330
331	/* We could not send a reliable packet, either because there are
332	   none or because there are too many unack'ed pkts. Did we receive
333	   any packets we have not acknowledged yet ? */
334
335	if (bcsp->txack_req) {
336		/* if so, craft an empty ACK pkt and send it on BCSP unreliable
337		   channel 0 */
338		struct sk_buff *nskb = bcsp_prepare_pkt(bcsp, NULL, 0, BCSP_ACK_PKT);
339		return nskb;
340	}
341
342	/* We have nothing to send */
343	return NULL;
344}
345
346static int bcsp_flush(struct hci_uart *hu)
347{
348	BT_DBG("hu %p", hu);
349	return 0;
350}
351
352/* Remove ack'ed packets */
353static void bcsp_pkt_cull(struct bcsp_struct *bcsp)
354{
355	struct sk_buff *skb, *tmp;
356	unsigned long flags;
357	int i, pkts_to_be_removed;
358	u8 seqno;
359
360	spin_lock_irqsave(&bcsp->unack.lock, flags);
361
362	pkts_to_be_removed = skb_queue_len(&bcsp->unack);
363	seqno = bcsp->msgq_txseq;
364
365	while (pkts_to_be_removed) {
366		if (bcsp->rxack == seqno)
367			break;
368		pkts_to_be_removed--;
369		seqno = (seqno - 1) & 0x07;
370	}
371
372	if (bcsp->rxack != seqno)
373		BT_ERR("Peer acked invalid packet");
374
375	BT_DBG("Removing %u pkts out of %u, up to seqno %u",
376	       pkts_to_be_removed, skb_queue_len(&bcsp->unack),
377	       (seqno - 1) & 0x07);
378
379	i = 0;
380	skb_queue_walk_safe(&bcsp->unack, skb, tmp) {
381		if (i >= pkts_to_be_removed)
382			break;
383		i++;
384
385		__skb_unlink(skb, &bcsp->unack);
386		kfree_skb(skb);
387	}
388
389	if (skb_queue_empty(&bcsp->unack))
390		del_timer(&bcsp->tbcsp);
391
392	spin_unlock_irqrestore(&bcsp->unack.lock, flags);
393
394	if (i != pkts_to_be_removed)
395		BT_ERR("Removed only %u out of %u pkts", i, pkts_to_be_removed);
396}
397
398/* Handle BCSP link-establishment packets. When we
399   detect a "sync" packet, symptom that the BT module has reset,
400   we do nothing :) (yet) */
401static void bcsp_handle_le_pkt(struct hci_uart *hu)
402{
403	struct bcsp_struct *bcsp = hu->priv;
404	u8 conf_pkt[4]     = { 0xad, 0xef, 0xac, 0xed };
405	u8 conf_rsp_pkt[4] = { 0xde, 0xad, 0xd0, 0xd0 };
406	u8 sync_pkt[4]     = { 0xda, 0xdc, 0xed, 0xed };
407
408	/* spot "conf" pkts and reply with a "conf rsp" pkt */
409	if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&
410			!memcmp(&bcsp->rx_skb->data[4], conf_pkt, 4)) {
411		struct sk_buff *nskb = alloc_skb(4, GFP_ATOMIC);
412
413		BT_DBG("Found a LE conf pkt");
414		if (!nskb)
415			return;
416		memcpy(skb_put(nskb, 4), conf_rsp_pkt, 4);
417		bt_cb(nskb)->pkt_type = BCSP_LE_PKT;
418
419		skb_queue_head(&bcsp->unrel, nskb);
420		hci_uart_tx_wakeup(hu);
421	}
422	/* Spot "sync" pkts. If we find one...disaster! */
423	else if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&
424			!memcmp(&bcsp->rx_skb->data[4], sync_pkt, 4)) {
425		BT_ERR("Found a LE sync pkt, card has reset");
426	}
427}
428
429static inline void bcsp_unslip_one_byte(struct bcsp_struct *bcsp, unsigned char byte)
430{
431	const u8 c0 = 0xc0, db = 0xdb;
432
433	switch (bcsp->rx_esc_state) {
434	case BCSP_ESCSTATE_NOESC:
435		switch (byte) {
436		case 0xdb:
437			bcsp->rx_esc_state = BCSP_ESCSTATE_ESC;
438			break;
439		default:
440			memcpy(skb_put(bcsp->rx_skb, 1), &byte, 1);
441			if ((bcsp->rx_skb-> data[0] & 0x40) != 0 &&
442					bcsp->rx_state != BCSP_W4_CRC)
443				bcsp_crc_update(&bcsp->message_crc, byte);
444			bcsp->rx_count--;
445		}
446		break;
447
448	case BCSP_ESCSTATE_ESC:
449		switch (byte) {
450		case 0xdc:
451			memcpy(skb_put(bcsp->rx_skb, 1), &c0, 1);
452			if ((bcsp->rx_skb-> data[0] & 0x40) != 0 &&
453					bcsp->rx_state != BCSP_W4_CRC)
454				bcsp_crc_update(&bcsp-> message_crc, 0xc0);
455			bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
456			bcsp->rx_count--;
457			break;
458
459		case 0xdd:
460			memcpy(skb_put(bcsp->rx_skb, 1), &db, 1);
461			if ((bcsp->rx_skb-> data[0] & 0x40) != 0 &&
462					bcsp->rx_state != BCSP_W4_CRC)
463				bcsp_crc_update(&bcsp-> message_crc, 0xdb);
464			bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
465			bcsp->rx_count--;
466			break;
467
468		default:
469			BT_ERR ("Invalid byte %02x after esc byte", byte);
470			kfree_skb(bcsp->rx_skb);
471			bcsp->rx_skb = NULL;
472			bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
473			bcsp->rx_count = 0;
474		}
475	}
476}
477
478static void bcsp_complete_rx_pkt(struct hci_uart *hu)
479{
480	struct bcsp_struct *bcsp = hu->priv;
481	int pass_up;
482
483	if (bcsp->rx_skb->data[0] & 0x80) {	/* reliable pkt */
484		BT_DBG("Received seqno %u from card", bcsp->rxseq_txack);
485		bcsp->rxseq_txack++;
486		bcsp->rxseq_txack %= 0x8;
487		bcsp->txack_req    = 1;
488
489		/* If needed, transmit an ack pkt */
490		hci_uart_tx_wakeup(hu);
491	}
492
493	bcsp->rxack = (bcsp->rx_skb->data[0] >> 3) & 0x07;
494	BT_DBG("Request for pkt %u from card", bcsp->rxack);
495
496	bcsp_pkt_cull(bcsp);
497	if ((bcsp->rx_skb->data[1] & 0x0f) == 6 &&
498			bcsp->rx_skb->data[0] & 0x80) {
499		bt_cb(bcsp->rx_skb)->pkt_type = HCI_ACLDATA_PKT;
500		pass_up = 1;
501	} else if ((bcsp->rx_skb->data[1] & 0x0f) == 5 &&
502			bcsp->rx_skb->data[0] & 0x80) {
503		bt_cb(bcsp->rx_skb)->pkt_type = HCI_EVENT_PKT;
504		pass_up = 1;
505	} else if ((bcsp->rx_skb->data[1] & 0x0f) == 7) {
506		bt_cb(bcsp->rx_skb)->pkt_type = HCI_SCODATA_PKT;
507		pass_up = 1;
508	} else if ((bcsp->rx_skb->data[1] & 0x0f) == 1 &&
509			!(bcsp->rx_skb->data[0] & 0x80)) {
510		bcsp_handle_le_pkt(hu);
511		pass_up = 0;
512	} else
513		pass_up = 0;
514
515	if (!pass_up) {
516		struct hci_event_hdr hdr;
517		u8 desc = (bcsp->rx_skb->data[1] & 0x0f);
518
519		if (desc != 0 && desc != 1) {
520			if (hciextn) {
521				desc |= 0xc0;
522				skb_pull(bcsp->rx_skb, 4);
523				memcpy(skb_push(bcsp->rx_skb, 1), &desc, 1);
524
525				hdr.evt = 0xff;
526				hdr.plen = bcsp->rx_skb->len;
527				memcpy(skb_push(bcsp->rx_skb, HCI_EVENT_HDR_SIZE), &hdr, HCI_EVENT_HDR_SIZE);
528				bt_cb(bcsp->rx_skb)->pkt_type = HCI_EVENT_PKT;
529
530				hci_recv_frame(hu->hdev, bcsp->rx_skb);
531			} else {
532				BT_ERR ("Packet for unknown channel (%u %s)",
533					bcsp->rx_skb->data[1] & 0x0f,
534					bcsp->rx_skb->data[0] & 0x80 ?
535					"reliable" : "unreliable");
536				kfree_skb(bcsp->rx_skb);
537			}
538		} else
539			kfree_skb(bcsp->rx_skb);
540	} else {
541		/* Pull out BCSP hdr */
542		skb_pull(bcsp->rx_skb, 4);
543
544		hci_recv_frame(hu->hdev, bcsp->rx_skb);
545	}
546
547	bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
548	bcsp->rx_skb = NULL;
549}
550
551static u16 bscp_get_crc(struct bcsp_struct *bcsp)
552{
553	return get_unaligned_be16(&bcsp->rx_skb->data[bcsp->rx_skb->len - 2]);
554}
555
556/* Recv data */
557static int bcsp_recv(struct hci_uart *hu, void *data, int count)
558{
559	struct bcsp_struct *bcsp = hu->priv;
560	unsigned char *ptr;
561
562	BT_DBG("hu %p count %d rx_state %d rx_count %ld",
563		hu, count, bcsp->rx_state, bcsp->rx_count);
564
565	ptr = data;
566	while (count) {
567		if (bcsp->rx_count) {
568			if (*ptr == 0xc0) {
569				BT_ERR("Short BCSP packet");
570				kfree_skb(bcsp->rx_skb);
571				bcsp->rx_state = BCSP_W4_PKT_START;
572				bcsp->rx_count = 0;
573			} else
574				bcsp_unslip_one_byte(bcsp, *ptr);
575
576			ptr++; count--;
577			continue;
578		}
579
580		switch (bcsp->rx_state) {
581		case BCSP_W4_BCSP_HDR:
582			if ((0xff & (u8) ~ (bcsp->rx_skb->data[0] + bcsp->rx_skb->data[1] +
583					bcsp->rx_skb->data[2])) != bcsp->rx_skb->data[3]) {
584				BT_ERR("Error in BCSP hdr checksum");
585				kfree_skb(bcsp->rx_skb);
586				bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
587				bcsp->rx_count = 0;
588				continue;
589			}
590			if (bcsp->rx_skb->data[0] & 0x80	/* reliable pkt */
591			    		&& (bcsp->rx_skb->data[0] & 0x07) != bcsp->rxseq_txack) {
592				BT_ERR ("Out-of-order packet arrived, got %u expected %u",
593					bcsp->rx_skb->data[0] & 0x07, bcsp->rxseq_txack);
594
595				kfree_skb(bcsp->rx_skb);
596				bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
597				bcsp->rx_count = 0;
598				continue;
599			}
600			bcsp->rx_state = BCSP_W4_DATA;
601			bcsp->rx_count = (bcsp->rx_skb->data[1] >> 4) +
602					(bcsp->rx_skb->data[2] << 4);	/* May be 0 */
603			continue;
604
605		case BCSP_W4_DATA:
606			if (bcsp->rx_skb->data[0] & 0x40) {	/* pkt with crc */
607				bcsp->rx_state = BCSP_W4_CRC;
608				bcsp->rx_count = 2;
609			} else
610				bcsp_complete_rx_pkt(hu);
611			continue;
612
613		case BCSP_W4_CRC:
614			if (bitrev16(bcsp->message_crc) != bscp_get_crc(bcsp)) {
615				BT_ERR ("Checksum failed: computed %04x received %04x",
616					bitrev16(bcsp->message_crc),
617					bscp_get_crc(bcsp));
618
619				kfree_skb(bcsp->rx_skb);
620				bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
621				bcsp->rx_count = 0;
622				continue;
623			}
624			skb_trim(bcsp->rx_skb, bcsp->rx_skb->len - 2);
625			bcsp_complete_rx_pkt(hu);
626			continue;
627
628		case BCSP_W4_PKT_DELIMITER:
629			switch (*ptr) {
630			case 0xc0:
631				bcsp->rx_state = BCSP_W4_PKT_START;
632				break;
633			default:
634				/*BT_ERR("Ignoring byte %02x", *ptr);*/
635				break;
636			}
637			ptr++; count--;
638			break;
639
640		case BCSP_W4_PKT_START:
641			switch (*ptr) {
642			case 0xc0:
643				ptr++; count--;
644				break;
645
646			default:
647				bcsp->rx_state = BCSP_W4_BCSP_HDR;
648				bcsp->rx_count = 4;
649				bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
650				BCSP_CRC_INIT(bcsp->message_crc);
651
652				/* Do not increment ptr or decrement count
653				 * Allocate packet. Max len of a BCSP pkt=
654				 * 0xFFF (payload) +4 (header) +2 (crc) */
655
656				bcsp->rx_skb = bt_skb_alloc(0x1005, GFP_ATOMIC);
657				if (!bcsp->rx_skb) {
658					BT_ERR("Can't allocate mem for new packet");
659					bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
660					bcsp->rx_count = 0;
661					return 0;
662				}
663				break;
664			}
665			break;
666		}
667	}
668	return count;
669}
670
671	/* Arrange to retransmit all messages in the relq. */
672static void bcsp_timed_event(unsigned long arg)
673{
674	struct hci_uart *hu = (struct hci_uart *) arg;
675	struct bcsp_struct *bcsp = hu->priv;
676	struct sk_buff *skb;
677	unsigned long flags;
678
679	BT_DBG("hu %p retransmitting %u pkts", hu, bcsp->unack.qlen);
680
681	spin_lock_irqsave_nested(&bcsp->unack.lock, flags, SINGLE_DEPTH_NESTING);
682
683	while ((skb = __skb_dequeue_tail(&bcsp->unack)) != NULL) {
684		bcsp->msgq_txseq = (bcsp->msgq_txseq - 1) & 0x07;
685		skb_queue_head(&bcsp->rel, skb);
686	}
687
688	spin_unlock_irqrestore(&bcsp->unack.lock, flags);
689
690	hci_uart_tx_wakeup(hu);
691}
692
693static int bcsp_open(struct hci_uart *hu)
694{
695	struct bcsp_struct *bcsp;
696
697	BT_DBG("hu %p", hu);
698
699	bcsp = kzalloc(sizeof(*bcsp), GFP_KERNEL);
700	if (!bcsp)
701		return -ENOMEM;
702
703	hu->priv = bcsp;
704	skb_queue_head_init(&bcsp->unack);
705	skb_queue_head_init(&bcsp->rel);
706	skb_queue_head_init(&bcsp->unrel);
707
708	init_timer(&bcsp->tbcsp);
709	bcsp->tbcsp.function = bcsp_timed_event;
710	bcsp->tbcsp.data     = (u_long) hu;
711
712	bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
713
714	if (txcrc)
715		bcsp->use_crc = 1;
716
717	return 0;
718}
719
720static int bcsp_close(struct hci_uart *hu)
721{
722	struct bcsp_struct *bcsp = hu->priv;
723
724	del_timer_sync(&bcsp->tbcsp);
725
726	hu->priv = NULL;
727
728	BT_DBG("hu %p", hu);
729
730	skb_queue_purge(&bcsp->unack);
731	skb_queue_purge(&bcsp->rel);
732	skb_queue_purge(&bcsp->unrel);
733
734	kfree(bcsp);
735	return 0;
736}
737
738static struct hci_uart_proto bcsp = {
739	.id		= HCI_UART_BCSP,
740	.open		= bcsp_open,
741	.close		= bcsp_close,
742	.enqueue	= bcsp_enqueue,
743	.dequeue	= bcsp_dequeue,
744	.recv		= bcsp_recv,
745	.flush		= bcsp_flush
746};
747
748int __init bcsp_init(void)
749{
750	int err = hci_uart_register_proto(&bcsp);
751
752	if (!err)
753		BT_INFO("HCI BCSP protocol initialized");
754	else
755		BT_ERR("HCI BCSP protocol registration failed");
756
757	return err;
758}
759
760int __exit bcsp_deinit(void)
761{
762	return hci_uart_unregister_proto(&bcsp);
763}
764
765module_param(txcrc, bool, 0644);
766MODULE_PARM_DESC(txcrc, "Transmit CRC with every BCSP packet");
767
768module_param(hciextn, bool, 0644);
769MODULE_PARM_DESC(hciextn, "Convert HCI Extensions into BCSP packets");
770