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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 *4 *  Bluetooth HCI UART driver5 *6 *  Copyright (C) 2002-2003  Fabrizio Gennari <fabrizio.gennari@philips.com>7 *  Copyright (C) 2004-2005  Marcel Holtmann <marcel@holtmann.org>8 */9 10#include <linux/module.h>11 12#include <linux/kernel.h>13#include <linux/init.h>14#include <linux/types.h>15#include <linux/fcntl.h>16#include <linux/interrupt.h>17#include <linux/ptrace.h>18#include <linux/poll.h>19 20#include <linux/slab.h>21#include <linux/tty.h>22#include <linux/errno.h>23#include <linux/string.h>24#include <linux/signal.h>25#include <linux/ioctl.h>26#include <linux/skbuff.h>27#include <linux/bitrev.h>28#include <linux/unaligned.h>29 30#include <net/bluetooth/bluetooth.h>31#include <net/bluetooth/hci_core.h>32 33#include "hci_uart.h"34 35static bool txcrc = true;36static bool hciextn = true;37 38#define BCSP_TXWINSIZE	439 40#define BCSP_ACK_PKT	0x0541#define BCSP_LE_PKT	0x0642 43struct bcsp_struct {44	struct sk_buff_head unack;	/* Unack'ed packets queue */45	struct sk_buff_head rel;	/* Reliable packets queue */46	struct sk_buff_head unrel;	/* Unreliable packets queue */47 48	unsigned long rx_count;49	struct	sk_buff *rx_skb;50	u8	rxseq_txack;		/* rxseq == txack. */51	u8	rxack;			/* Last packet sent by us that the peer ack'ed */52	struct	timer_list tbcsp;53	struct	hci_uart *hu;54 55	enum {56		BCSP_W4_PKT_DELIMITER,57		BCSP_W4_PKT_START,58		BCSP_W4_BCSP_HDR,59		BCSP_W4_DATA,60		BCSP_W4_CRC61	} rx_state;62 63	enum {64		BCSP_ESCSTATE_NOESC,65		BCSP_ESCSTATE_ESC66	} rx_esc_state;67 68	u8	use_crc;69	u16	message_crc;70	u8	txack_req;		/* Do we need to send ack's to the peer? */71 72	/* Reliable packet sequence number - used to assign seq to each rel pkt. */73	u8	msgq_txseq;74};75 76/* ---- BCSP CRC calculation ---- */77 78/* Table for calculating CRC for polynomial 0x1021, LSB processed first,79 * initial value 0xffff, bits shifted in reverse order.80 */81 82static const u16 crc_table[] = {83	0x0000, 0x1081, 0x2102, 0x3183,84	0x4204, 0x5285, 0x6306, 0x7387,85	0x8408, 0x9489, 0xa50a, 0xb58b,86	0xc60c, 0xd68d, 0xe70e, 0xf78f87};88 89/* Initialise the crc calculator */90#define BCSP_CRC_INIT(x) x = 0xffff91 92/* Update crc with next data byte93 *94 * Implementation note95 *     The data byte is treated as two nibbles.  The crc is generated96 *     in reverse, i.e., bits are fed into the register from the top.97 */98static void bcsp_crc_update(u16 *crc, u8 d)99{100	u16 reg = *crc;101 102	reg = (reg >> 4) ^ crc_table[(reg ^ d) & 0x000f];103	reg = (reg >> 4) ^ crc_table[(reg ^ (d >> 4)) & 0x000f];104 105	*crc = reg;106}107 108/* ---- BCSP core ---- */109 110static void bcsp_slip_msgdelim(struct sk_buff *skb)111{112	const char pkt_delim = 0xc0;113 114	skb_put_data(skb, &pkt_delim, 1);115}116 117static void bcsp_slip_one_byte(struct sk_buff *skb, u8 c)118{119	const char esc_c0[2] = { 0xdb, 0xdc };120	const char esc_db[2] = { 0xdb, 0xdd };121 122	switch (c) {123	case 0xc0:124		skb_put_data(skb, &esc_c0, 2);125		break;126	case 0xdb:127		skb_put_data(skb, &esc_db, 2);128		break;129	default:130		skb_put_data(skb, &c, 1);131	}132}133 134static int bcsp_enqueue(struct hci_uart *hu, struct sk_buff *skb)135{136	struct bcsp_struct *bcsp = hu->priv;137 138	if (skb->len > 0xFFF) {139		BT_ERR("Packet too long");140		kfree_skb(skb);141		return 0;142	}143 144	switch (hci_skb_pkt_type(skb)) {145	case HCI_ACLDATA_PKT:146	case HCI_COMMAND_PKT:147		skb_queue_tail(&bcsp->rel, skb);148		break;149 150	case HCI_SCODATA_PKT:151		skb_queue_tail(&bcsp->unrel, skb);152		break;153 154	default:155		BT_ERR("Unknown packet type");156		kfree_skb(skb);157		break;158	}159 160	return 0;161}162 163static struct sk_buff *bcsp_prepare_pkt(struct bcsp_struct *bcsp, u8 *data,164					int len, int pkt_type)165{166	struct sk_buff *nskb;167	u8 hdr[4], chan;168	u16 BCSP_CRC_INIT(bcsp_txmsg_crc);169	int rel, i;170 171	switch (pkt_type) {172	case HCI_ACLDATA_PKT:173		chan = 6;	/* BCSP ACL channel */174		rel = 1;	/* reliable channel */175		break;176	case HCI_COMMAND_PKT:177		chan = 5;	/* BCSP cmd/evt channel */178		rel = 1;	/* reliable channel */179		break;180	case HCI_SCODATA_PKT:181		chan = 7;	/* BCSP SCO channel */182		rel = 0;	/* unreliable channel */183		break;184	case BCSP_LE_PKT:185		chan = 1;	/* BCSP LE channel */186		rel = 0;	/* unreliable channel */187		break;188	case BCSP_ACK_PKT:189		chan = 0;	/* BCSP internal channel */190		rel = 0;	/* unreliable channel */191		break;192	default:193		BT_ERR("Unknown packet type");194		return NULL;195	}196 197	if (hciextn && chan == 5) {198		__le16 opcode = ((struct hci_command_hdr *)data)->opcode;199 200		/* Vendor specific commands */201		if (hci_opcode_ogf(__le16_to_cpu(opcode)) == 0x3f) {202			u8 desc = *(data + HCI_COMMAND_HDR_SIZE);203 204			if ((desc & 0xf0) == 0xc0) {205				data += HCI_COMMAND_HDR_SIZE + 1;206				len  -= HCI_COMMAND_HDR_SIZE + 1;207				chan = desc & 0x0f;208			}209		}210	}211 212	/* Max len of packet: (original len +4(bcsp hdr) +2(crc))*2213	 * (because bytes 0xc0 and 0xdb are escaped, worst case is214	 * when the packet is all made of 0xc0 and 0xdb :) )215	 * + 2 (0xc0 delimiters at start and end).216	 */217 218	nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);219	if (!nskb)220		return NULL;221 222	hci_skb_pkt_type(nskb) = pkt_type;223 224	bcsp_slip_msgdelim(nskb);225 226	hdr[0] = bcsp->rxseq_txack << 3;227	bcsp->txack_req = 0;228	BT_DBG("We request packet no %u to card", bcsp->rxseq_txack);229 230	if (rel) {231		hdr[0] |= 0x80 + bcsp->msgq_txseq;232		BT_DBG("Sending packet with seqno %u", bcsp->msgq_txseq);233		bcsp->msgq_txseq = (bcsp->msgq_txseq + 1) & 0x07;234	}235 236	if (bcsp->use_crc)237		hdr[0] |= 0x40;238 239	hdr[1] = ((len << 4) & 0xff) | chan;240	hdr[2] = len >> 4;241	hdr[3] = ~(hdr[0] + hdr[1] + hdr[2]);242 243	/* Put BCSP header */244	for (i = 0; i < 4; i++) {245		bcsp_slip_one_byte(nskb, hdr[i]);246 247		if (bcsp->use_crc)248			bcsp_crc_update(&bcsp_txmsg_crc, hdr[i]);249	}250 251	/* Put payload */252	for (i = 0; i < len; i++) {253		bcsp_slip_one_byte(nskb, data[i]);254 255		if (bcsp->use_crc)256			bcsp_crc_update(&bcsp_txmsg_crc, data[i]);257	}258 259	/* Put CRC */260	if (bcsp->use_crc) {261		bcsp_txmsg_crc = bitrev16(bcsp_txmsg_crc);262		bcsp_slip_one_byte(nskb, (u8)((bcsp_txmsg_crc >> 8) & 0x00ff));263		bcsp_slip_one_byte(nskb, (u8)(bcsp_txmsg_crc & 0x00ff));264	}265 266	bcsp_slip_msgdelim(nskb);267	return nskb;268}269 270/* This is a rewrite of pkt_avail in ABCSP */271static struct sk_buff *bcsp_dequeue(struct hci_uart *hu)272{273	struct bcsp_struct *bcsp = hu->priv;274	unsigned long flags;275	struct sk_buff *skb;276 277	/* First of all, check for unreliable messages in the queue,278	 * since they have priority279	 */280 281	skb = skb_dequeue(&bcsp->unrel);282	if (skb != NULL) {283		struct sk_buff *nskb;284 285		nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len,286					hci_skb_pkt_type(skb));287		if (nskb) {288			kfree_skb(skb);289			return nskb;290		} else {291			skb_queue_head(&bcsp->unrel, skb);292			BT_ERR("Could not dequeue pkt because alloc_skb failed");293		}294	}295 296	/* Now, try to send a reliable pkt. We can only send a297	 * reliable packet if the number of packets sent but not yet ack'ed298	 * is < than the winsize299	 */300 301	spin_lock_irqsave_nested(&bcsp->unack.lock, flags, SINGLE_DEPTH_NESTING);302 303	if (bcsp->unack.qlen < BCSP_TXWINSIZE) {304		skb = skb_dequeue(&bcsp->rel);305		if (skb != NULL) {306			struct sk_buff *nskb;307 308			nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len,309						hci_skb_pkt_type(skb));310			if (nskb) {311				__skb_queue_tail(&bcsp->unack, skb);312				mod_timer(&bcsp->tbcsp, jiffies + HZ / 4);313				spin_unlock_irqrestore(&bcsp->unack.lock, flags);314				return nskb;315			} else {316				skb_queue_head(&bcsp->rel, skb);317				BT_ERR("Could not dequeue pkt because alloc_skb failed");318			}319		}320	}321 322	spin_unlock_irqrestore(&bcsp->unack.lock, flags);323 324	/* We could not send a reliable packet, either because there are325	 * none or because there are too many unack'ed pkts. Did we receive326	 * any packets we have not acknowledged yet ?327	 */328 329	if (bcsp->txack_req) {330		/* if so, craft an empty ACK pkt and send it on BCSP unreliable331		 * channel 0332		 */333		struct sk_buff *nskb = bcsp_prepare_pkt(bcsp, NULL, 0, BCSP_ACK_PKT);334		return nskb;335	}336 337	/* We have nothing to send */338	return NULL;339}340 341static int bcsp_flush(struct hci_uart *hu)342{343	BT_DBG("hu %p", hu);344	return 0;345}346 347/* Remove ack'ed packets */348static void bcsp_pkt_cull(struct bcsp_struct *bcsp)349{350	struct sk_buff *skb, *tmp;351	unsigned long flags;352	int i, pkts_to_be_removed;353	u8 seqno;354 355	spin_lock_irqsave(&bcsp->unack.lock, flags);356 357	pkts_to_be_removed = skb_queue_len(&bcsp->unack);358	seqno = bcsp->msgq_txseq;359 360	while (pkts_to_be_removed) {361		if (bcsp->rxack == seqno)362			break;363		pkts_to_be_removed--;364		seqno = (seqno - 1) & 0x07;365	}366 367	if (bcsp->rxack != seqno)368		BT_ERR("Peer acked invalid packet");369 370	BT_DBG("Removing %u pkts out of %u, up to seqno %u",371	       pkts_to_be_removed, skb_queue_len(&bcsp->unack),372	       (seqno - 1) & 0x07);373 374	i = 0;375	skb_queue_walk_safe(&bcsp->unack, skb, tmp) {376		if (i >= pkts_to_be_removed)377			break;378		i++;379 380		__skb_unlink(skb, &bcsp->unack);381		dev_kfree_skb_irq(skb);382	}383 384	if (skb_queue_empty(&bcsp->unack))385		del_timer(&bcsp->tbcsp);386 387	spin_unlock_irqrestore(&bcsp->unack.lock, flags);388 389	if (i != pkts_to_be_removed)390		BT_ERR("Removed only %u out of %u pkts", i, pkts_to_be_removed);391}392 393/* Handle BCSP link-establishment packets. When we394 * detect a "sync" packet, symptom that the BT module has reset,395 * we do nothing :) (yet)396 */397static void bcsp_handle_le_pkt(struct hci_uart *hu)398{399	struct bcsp_struct *bcsp = hu->priv;400	u8 conf_pkt[4]     = { 0xad, 0xef, 0xac, 0xed };401	u8 conf_rsp_pkt[4] = { 0xde, 0xad, 0xd0, 0xd0 };402	u8 sync_pkt[4]     = { 0xda, 0xdc, 0xed, 0xed };403 404	/* spot "conf" pkts and reply with a "conf rsp" pkt */405	if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&406	    !memcmp(&bcsp->rx_skb->data[4], conf_pkt, 4)) {407		struct sk_buff *nskb = alloc_skb(4, GFP_ATOMIC);408 409		BT_DBG("Found a LE conf pkt");410		if (!nskb)411			return;412		skb_put_data(nskb, conf_rsp_pkt, 4);413		hci_skb_pkt_type(nskb) = BCSP_LE_PKT;414 415		skb_queue_head(&bcsp->unrel, nskb);416		hci_uart_tx_wakeup(hu);417	}418	/* Spot "sync" pkts. If we find one...disaster! */419	else if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&420		 !memcmp(&bcsp->rx_skb->data[4], sync_pkt, 4)) {421		BT_ERR("Found a LE sync pkt, card has reset");422	}423}424 425static inline void bcsp_unslip_one_byte(struct bcsp_struct *bcsp, unsigned char byte)426{427	const u8 c0 = 0xc0, db = 0xdb;428 429	switch (bcsp->rx_esc_state) {430	case BCSP_ESCSTATE_NOESC:431		switch (byte) {432		case 0xdb:433			bcsp->rx_esc_state = BCSP_ESCSTATE_ESC;434			break;435		default:436			skb_put_data(bcsp->rx_skb, &byte, 1);437			if ((bcsp->rx_skb->data[0] & 0x40) != 0 &&438			    bcsp->rx_state != BCSP_W4_CRC)439				bcsp_crc_update(&bcsp->message_crc, byte);440			bcsp->rx_count--;441		}442		break;443 444	case BCSP_ESCSTATE_ESC:445		switch (byte) {446		case 0xdc:447			skb_put_data(bcsp->rx_skb, &c0, 1);448			if ((bcsp->rx_skb->data[0] & 0x40) != 0 &&449			    bcsp->rx_state != BCSP_W4_CRC)450				bcsp_crc_update(&bcsp->message_crc, 0xc0);451			bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;452			bcsp->rx_count--;453			break;454 455		case 0xdd:456			skb_put_data(bcsp->rx_skb, &db, 1);457			if ((bcsp->rx_skb->data[0] & 0x40) != 0 &&458			    bcsp->rx_state != BCSP_W4_CRC)459				bcsp_crc_update(&bcsp->message_crc, 0xdb);460			bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;461			bcsp->rx_count--;462			break;463 464		default:465			BT_ERR("Invalid byte %02x after esc byte", byte);466			kfree_skb(bcsp->rx_skb);467			bcsp->rx_skb = NULL;468			bcsp->rx_state = BCSP_W4_PKT_DELIMITER;469			bcsp->rx_count = 0;470		}471	}472}473 474static void bcsp_complete_rx_pkt(struct hci_uart *hu)475{476	struct bcsp_struct *bcsp = hu->priv;477	int pass_up = 0;478 479	if (bcsp->rx_skb->data[0] & 0x80) {	/* reliable pkt */480		BT_DBG("Received seqno %u from card", bcsp->rxseq_txack);481 482		/* check the rx sequence number is as expected */483		if ((bcsp->rx_skb->data[0] & 0x07) == bcsp->rxseq_txack) {484			bcsp->rxseq_txack++;485			bcsp->rxseq_txack %= 0x8;486		} else {487			/* handle re-transmitted packet or488			 * when packet was missed489			 */490			BT_ERR("Out-of-order packet arrived, got %u expected %u",491			       bcsp->rx_skb->data[0] & 0x07, bcsp->rxseq_txack);492 493			/* do not process out-of-order packet payload */494			pass_up = 2;495		}496 497		/* send current txack value to all received reliable packets */498		bcsp->txack_req = 1;499 500		/* If needed, transmit an ack pkt */501		hci_uart_tx_wakeup(hu);502	}503 504	bcsp->rxack = (bcsp->rx_skb->data[0] >> 3) & 0x07;505	BT_DBG("Request for pkt %u from card", bcsp->rxack);506 507	/* handle received ACK indications,508	 * including those from out-of-order packets509	 */510	bcsp_pkt_cull(bcsp);511 512	if (pass_up != 2) {513		if ((bcsp->rx_skb->data[1] & 0x0f) == 6 &&514		    (bcsp->rx_skb->data[0] & 0x80)) {515			hci_skb_pkt_type(bcsp->rx_skb) = HCI_ACLDATA_PKT;516			pass_up = 1;517		} else if ((bcsp->rx_skb->data[1] & 0x0f) == 5 &&518			   (bcsp->rx_skb->data[0] & 0x80)) {519			hci_skb_pkt_type(bcsp->rx_skb) = HCI_EVENT_PKT;520			pass_up = 1;521		} else if ((bcsp->rx_skb->data[1] & 0x0f) == 7) {522			hci_skb_pkt_type(bcsp->rx_skb) = HCI_SCODATA_PKT;523			pass_up = 1;524		} else if ((bcsp->rx_skb->data[1] & 0x0f) == 1 &&525			   !(bcsp->rx_skb->data[0] & 0x80)) {526			bcsp_handle_le_pkt(hu);527			pass_up = 0;528		} else {529			pass_up = 0;530		}531	}532 533	if (pass_up == 0) {534		struct hci_event_hdr hdr;535		u8 desc = (bcsp->rx_skb->data[1] & 0x0f);536 537		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);542 543				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				hci_skb_pkt_type(bcsp->rx_skb) = HCI_EVENT_PKT;547 548				hci_recv_frame(hu->hdev, 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		} else557			kfree_skb(bcsp->rx_skb);558	} else if (pass_up == 1) {559		/* Pull out BCSP hdr */560		skb_pull(bcsp->rx_skb, 4);561 562		hci_recv_frame(hu->hdev, bcsp->rx_skb);563	} else {564		/* ignore packet payload of already ACKed re-transmitted565		 * packets or when a packet was missed in the BCSP window566		 */567		kfree_skb(bcsp->rx_skb);568	}569 570	bcsp->rx_state = BCSP_W4_PKT_DELIMITER;571	bcsp->rx_skb = NULL;572}573 574static u16 bscp_get_crc(struct bcsp_struct *bcsp)575{576	return get_unaligned_be16(&bcsp->rx_skb->data[bcsp->rx_skb->len - 2]);577}578 579/* Recv data */580static int bcsp_recv(struct hci_uart *hu, const void *data, int count)581{582	struct bcsp_struct *bcsp = hu->priv;583	const unsigned char *ptr;584 585	BT_DBG("hu %p count %d rx_state %d rx_count %ld",586	       hu, count, bcsp->rx_state, bcsp->rx_count);587 588	ptr = data;589	while (count) {590		if (bcsp->rx_count) {591			if (*ptr == 0xc0) {592				BT_ERR("Short BCSP packet");593				kfree_skb(bcsp->rx_skb);594				bcsp->rx_skb = NULL;595				bcsp->rx_state = BCSP_W4_PKT_START;596				bcsp->rx_count = 0;597			} else598				bcsp_unslip_one_byte(bcsp, *ptr);599 600			ptr++; count--;601			continue;602		}603 604		switch (bcsp->rx_state) {605		case BCSP_W4_BCSP_HDR:606			if ((0xff & (u8)~(bcsp->rx_skb->data[0] + bcsp->rx_skb->data[1] +607			    bcsp->rx_skb->data[2])) != bcsp->rx_skb->data[3]) {608				BT_ERR("Error in BCSP hdr checksum");609				kfree_skb(bcsp->rx_skb);610				bcsp->rx_skb = NULL;611				bcsp->rx_state = BCSP_W4_PKT_DELIMITER;612				bcsp->rx_count = 0;613				continue;614			}615			bcsp->rx_state = BCSP_W4_DATA;616			bcsp->rx_count = (bcsp->rx_skb->data[1] >> 4) +617					(bcsp->rx_skb->data[2] << 4);	/* May be 0 */618			continue;619 620		case BCSP_W4_DATA:621			if (bcsp->rx_skb->data[0] & 0x40) {	/* pkt with crc */622				bcsp->rx_state = BCSP_W4_CRC;623				bcsp->rx_count = 2;624			} else625				bcsp_complete_rx_pkt(hu);626			continue;627 628		case BCSP_W4_CRC:629			if (bitrev16(bcsp->message_crc) != bscp_get_crc(bcsp)) {630				BT_ERR("Checksum failed: computed %04x received %04x",631				       bitrev16(bcsp->message_crc),632				       bscp_get_crc(bcsp));633 634				kfree_skb(bcsp->rx_skb);635				bcsp->rx_skb = NULL;636				bcsp->rx_state = BCSP_W4_PKT_DELIMITER;637				bcsp->rx_count = 0;638				continue;639			}640			skb_trim(bcsp->rx_skb, bcsp->rx_skb->len - 2);641			bcsp_complete_rx_pkt(hu);642			continue;643 644		case BCSP_W4_PKT_DELIMITER:645			switch (*ptr) {646			case 0xc0:647				bcsp->rx_state = BCSP_W4_PKT_START;648				break;649			default:650				/*BT_ERR("Ignoring byte %02x", *ptr);*/651				break;652			}653			ptr++; count--;654			break;655 656		case BCSP_W4_PKT_START:657			switch (*ptr) {658			case 0xc0:659				ptr++; count--;660				break;661 662			default:663				bcsp->rx_state = BCSP_W4_BCSP_HDR;664				bcsp->rx_count = 4;665				bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;666				BCSP_CRC_INIT(bcsp->message_crc);667 668				/* Do not increment ptr or decrement count669				 * Allocate packet. Max len of a BCSP pkt=670				 * 0xFFF (payload) +4 (header) +2 (crc)671				 */672 673				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				break;681			}682			break;683		}684	}685	return count;686}687 688	/* Arrange to retransmit all messages in the relq. */689static void bcsp_timed_event(struct timer_list *t)690{691	struct bcsp_struct *bcsp = from_timer(bcsp, t, tbcsp);692	struct hci_uart *hu = bcsp->hu;693	struct sk_buff *skb;694	unsigned long flags;695 696	BT_DBG("hu %p retransmitting %u pkts", hu, bcsp->unack.qlen);697 698	spin_lock_irqsave_nested(&bcsp->unack.lock, flags, SINGLE_DEPTH_NESTING);699 700	while ((skb = __skb_dequeue_tail(&bcsp->unack)) != NULL) {701		bcsp->msgq_txseq = (bcsp->msgq_txseq - 1) & 0x07;702		skb_queue_head(&bcsp->rel, skb);703	}704 705	spin_unlock_irqrestore(&bcsp->unack.lock, flags);706 707	hci_uart_tx_wakeup(hu);708}709 710static int bcsp_open(struct hci_uart *hu)711{712	struct bcsp_struct *bcsp;713 714	BT_DBG("hu %p", hu);715 716	bcsp = kzalloc(sizeof(*bcsp), GFP_KERNEL);717	if (!bcsp)718		return -ENOMEM;719 720	hu->priv = bcsp;721	bcsp->hu = hu;722	skb_queue_head_init(&bcsp->unack);723	skb_queue_head_init(&bcsp->rel);724	skb_queue_head_init(&bcsp->unrel);725 726	timer_setup(&bcsp->tbcsp, bcsp_timed_event, 0);727 728	bcsp->rx_state = BCSP_W4_PKT_DELIMITER;729 730	if (txcrc)731		bcsp->use_crc = 1;732 733	return 0;734}735 736static int bcsp_close(struct hci_uart *hu)737{738	struct bcsp_struct *bcsp = hu->priv;739 740	timer_shutdown_sync(&bcsp->tbcsp);741 742	hu->priv = NULL;743 744	BT_DBG("hu %p", hu);745 746	skb_queue_purge(&bcsp->unack);747	skb_queue_purge(&bcsp->rel);748	skb_queue_purge(&bcsp->unrel);749 750	if (bcsp->rx_skb) {751		kfree_skb(bcsp->rx_skb);752		bcsp->rx_skb = NULL;753	}754 755	kfree(bcsp);756	return 0;757}758 759static const struct hci_uart_proto bcsp = {760	.id		= HCI_UART_BCSP,761	.name		= "BCSP",762	.open		= bcsp_open,763	.close		= bcsp_close,764	.enqueue	= bcsp_enqueue,765	.dequeue	= bcsp_dequeue,766	.recv		= bcsp_recv,767	.flush		= bcsp_flush768};769 770int __init bcsp_init(void)771{772	return hci_uart_register_proto(&bcsp);773}774 775int __exit bcsp_deinit(void)776{777	return hci_uart_unregister_proto(&bcsp);778}779 780module_param(txcrc, bool, 0644);781MODULE_PARM_DESC(txcrc, "Transmit CRC with every BCSP packet");782 783module_param(hciextn, bool, 0644);784MODULE_PARM_DESC(hciextn, "Convert HCI Extensions into BCSP packets");785