// SPDX-License-Identifier: GPL-2.0-or-later
/*
*
* Bluetooth HCI UART driver
*
* Copyright (C) 2002-2003 Fabrizio Gennari <fabrizio.gennari@philips.com>
* Copyright (C) 2004-2005 Marcel Holtmann <marcel@holtmann.org>
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/interrupt.h>
#include <linux/ptrace.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/signal.h>
#include <linux/ioctl.h>
#include <linux/skbuff.h>
#include <linux/bitrev.h>
#include <asm/unaligned.h>
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include "hci_uart.h"
static bool txcrc = true;
static bool hciextn = true;
#define BCSP_TXWINSIZE 4
#define BCSP_ACK_PKT 0x05
#define BCSP_LE_PKT 0x06
struct bcsp_struct {
struct sk_buff_head unack; /* Unack'ed packets queue */
struct sk_buff_head rel; /* Reliable packets queue */
struct sk_buff_head unrel; /* Unreliable packets queue */
unsigned long rx_count;
struct sk_buff *rx_skb;
u8 rxseq_txack; /* rxseq == txack. */
u8 rxack; /* Last packet sent by us that the peer ack'ed */
struct timer_list tbcsp;
struct hci_uart *hu;
enum {
BCSP_W4_PKT_DELIMITER,
BCSP_W4_PKT_START,
BCSP_W4_BCSP_HDR,
BCSP_W4_DATA,
BCSP_W4_CRC
} rx_state;
enum {
BCSP_ESCSTATE_NOESC,
BCSP_ESCSTATE_ESC
} rx_esc_state;
u8 use_crc;
u16 message_crc;
u8 txack_req; /* Do we need to send ack's to the peer? */
/* Reliable packet sequence number - used to assign seq to each rel pkt. */
u8 msgq_txseq;
};
/* ---- BCSP CRC calculation ---- */
/* Table for calculating CRC for polynomial 0x1021, LSB processed first,
* initial value 0xffff, bits shifted in reverse order.
*/
static const u16 crc_table[] = {
0x0000, 0x1081, 0x2102, 0x3183,
0x4204, 0x5285, 0x6306, 0x7387,
0x8408, 0x9489, 0xa50a, 0xb58b,
0xc60c, 0xd68d, 0xe70e, 0xf78f
};
/* Initialise the crc calculator */
#define BCSP_CRC_INIT(x) x = 0xffff
/* Update crc with next data byte
*
* Implementation note
* The data byte is treated as two nibbles. The crc is generated
* in reverse, i.e., bits are fed into the register from the top.
*/
static void bcsp_crc_update(u16 *crc, u8 d)
{
u16 reg = *crc;
reg = (reg >> 4) ^ crc_table[(reg ^ d) & 0x000f];
reg = (reg >> 4) ^ crc_table[(reg ^ (d >> 4)) & 0x000f];
*crc = reg;
}
/* ---- BCSP core ---- */
static void bcsp_slip_msgdelim(struct sk_buff *skb)
{
const char pkt_delim = 0xc0;
skb_put_data(skb, &pkt_delim, 1);
}
static void bcsp_slip_one_byte(struct sk_buff *skb, u8 c)
{
const char esc_c0[2] = { 0xdb, 0xdc };
const char esc_db[2] = { 0xdb, 0xdd };
switch (c) {
case 0xc0:
skb_put_data(skb, &esc_c0, 2);
break;
case 0xdb:
skb_put_data(skb, &esc_db, 2);
break;
default:
skb_put_data(skb, &c, 1);
}
}
static int bcsp_enqueue(struct hci_uart *hu, struct sk_buff *skb)
{
struct bcsp_struct *bcsp = hu->priv;
if (skb->len > 0xFFF) {
BT_ERR("Packet too long");
kfree_skb(skb);
return 0;
}
switch (hci_skb_pkt_type(skb)) {
case HCI_ACLDATA_PKT:
case HCI_COMMAND_PKT:
skb_queue_tail(&bcsp->rel, skb);
break;
case HCI_SCODATA_PKT:
skb_queue_tail(&bcsp->unrel, skb);
break;
default:
BT_ERR("Unknown packet type");
kfree_skb(skb);
break;
}
return 0;
}
static struct sk_buff *bcsp_prepare_pkt(struct bcsp_struct *bcsp, u8 *data,
int len, int pkt_type)
{
struct sk_buff *nskb;
u8 hdr[4], chan;
u16 BCSP_CRC_INIT(bcsp_txmsg_crc);
int rel, i;
switch (pkt_type) {
case HCI_ACLDATA_PKT:
chan = 6; /* BCSP ACL channel */
rel = 1; /* reliable channel */
break;
case HCI_COMMAND_PKT:
chan = 5; /* BCSP cmd/evt channel */
rel = 1; /* reliable channel */
break;
case HCI_SCODATA_PKT:
chan = 7; /* BCSP SCO channel */
rel = 0; /* unreliable channel */
break;
case BCSP_LE_PKT:
chan = 1; /* BCSP LE channel */
rel = 0; /* unreliable channel */
break;
case BCSP_ACK_PKT:
chan = 0; /* BCSP internal channel */
rel = 0; /* unreliable channel */
break;
default:
BT_ERR("Unknown packet type");
return NULL;
}
if (hciextn && chan == 5) {
__le16 opcode = ((struct hci_command_hdr *)data)->opcode;
/* Vendor specific commands */
if (hci_opcode_ogf(__le16_to_cpu(opcode)) == 0x3f) {
u8 desc = *(data + HCI_COMMAND_HDR_SIZE);
if ((desc & 0xf0) == 0xc0) {
data += HCI_COMMAND_HDR_SIZE + 1;
len -= HCI_COMMAND_HDR_SIZE + 1;
chan = desc & 0x0f;
}
}
}
/* Max len of packet: (original len +4(bcsp hdr) +2(crc))*2
* (because bytes 0xc0 and 0xdb are escaped, worst case is
* when the packet is all made of 0xc0 and 0xdb :) )
* + 2 (0xc0 delimiters at start and end).
*/
nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);
if (!nskb)
return NULL;
hci_skb_pkt_type(nskb) = pkt_type;
bcsp_slip_msgdelim(nskb);
hdr[0] = bcsp->rxseq_txack << 3;
bcsp->txack_req = 0;
BT_DBG("We request packet no %u to card", bcsp->rxseq_txack);
if (rel) {
hdr[0] |= 0x80 + bcsp->msgq_txseq;
BT_DBG("Sending packet with seqno %u", bcsp->msgq_txseq);
bcsp->msgq_txseq = (bcsp->msgq_txseq + 1) & 0x07;
}
if (bcsp->use_crc)
hdr[0] |= 0x40;
hdr[1] = ((len << 4) & 0xff) | chan;
hdr[2] = len >> 4;
hdr[3] = ~(hdr[0] + hdr[1] + hdr[2]);
/* Put BCSP header */
for (i = 0; i < 4; i++) {
bcsp_slip_one_byte(nskb, hdr[i]);
if (bcsp->use_crc)
bcsp_crc_update(&bcsp_txmsg_crc, hdr[i]);
}
/* Put payload */
for (i = 0; i < len; i++) {
bcsp_slip_one_byte(nskb, data[i]);
if (bcsp->use_crc)
bcsp_crc_update(&bcsp_txmsg_crc, data[i]);
}
/* Put CRC */
if (bcsp->use_crc) {
bcsp_txmsg_crc = bitrev16(bcsp_txmsg_crc);
bcsp_slip_one_byte(nskb, (u8)((bcsp_txmsg_crc >> 8) & 0x00ff));
bcsp_slip_one_byte(nskb, (u8)(bcsp_txmsg_crc & 0x00ff));
}
bcsp_slip_msgdelim(nskb);
return nskb;
}
/* This is a rewrite of pkt_avail in ABCSP */
static struct sk_buff *bcsp_dequeue(struct hci_uart *hu)
{
struct bcsp_struct *bcsp = hu->priv;
unsigned long flags;
struct sk_buff *skb;
/* First of all, check for unreliable messages in the queue,
* since they have priority
*/
skb = skb_dequeue(&bcsp->unrel);
if (skb != NULL) {
struct sk_buff *nskb;
nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len,
hci_skb_pkt_type(skb));
if (nskb) {
kfree_skb(skb);
return nskb;
} else {
skb_queue_head(&bcsp->unrel, skb);
BT_ERR("Could not dequeue pkt because alloc_skb failed");
}
}
/* Now, try to send a reliable pkt. We can only send a
* reliable packet if the number of packets sent but not yet ack'ed
* is < than the winsize
*/
spin_lock_irqsave_nested(&bcsp->unack.lock, flags, SINGLE_DEPTH_NESTING);
if (bcsp->unack.qlen < BCSP_TXWINSIZE) {
skb = skb_dequeue(&bcsp->rel);
if (skb != NULL) {
struct sk_buff *nskb;
nskb = bcsp_prepare_pkt(bcsp, skb->data, skb->len,
hci_skb_pkt_type(skb));
if (nskb) {
__skb_queue_tail(&bcsp->unack, skb);
mod_timer(&bcsp->tbcsp, jiffies + HZ / 4);
spin_unlock_irqrestore(&bcsp->unack.lock, flags);
return nskb;
} else {
skb_queue_head(&bcsp->rel, skb);
BT_ERR("Could not dequeue pkt because alloc_skb failed");
}
}
}
spin_unlock_irqrestore(&bcsp->unack.lock, flags);
/* We could not send a reliable packet, either because there are
* none or because there are too many unack'ed pkts. Did we receive
* any packets we have not acknowledged yet ?
*/
if (bcsp->txack_req) {
/* if so, craft an empty ACK pkt and send it on BCSP unreliable
* channel 0
*/
struct sk_buff *nskb = bcsp_prepare_pkt(bcsp, NULL, 0, BCSP_ACK_PKT);
return nskb;
}
/* We have nothing to send */
return NULL;
}
static int bcsp_flush(struct hci_uart *hu)
{
BT_DBG("hu %p", hu);
return 0;
}
/* Remove ack'ed packets */
static void bcsp_pkt_cull(struct bcsp_struct *bcsp)
{
struct sk_buff *skb, *tmp;
unsigned long flags;
int i, pkts_to_be_removed;
u8 seqno;
spin_lock_irqsave(&bcsp->unack.lock, flags);
pkts_to_be_removed = skb_queue_len(&bcsp->unack);
seqno = bcsp->msgq_txseq;
while (pkts_to_be_removed) {
if (bcsp->rxack == seqno)
break;
pkts_to_be_removed--;
seqno = (seqno - 1) & 0x07;
}
if (bcsp->rxack != seqno)
BT_ERR("Peer acked invalid packet");
BT_DBG("Removing %u pkts out of %u, up to seqno %u",
pkts_to_be_removed, skb_queue_len(&bcsp->unack),
(seqno - 1) & 0x07);
i = 0;
skb_queue_walk_safe(&bcsp->unack, skb, tmp) {
if (i >= pkts_to_be_removed)
break;
i++;
__skb_unlink(skb, &bcsp->unack);
kfree_skb(skb);
}
if (skb_queue_empty(&bcsp->unack))
del_timer(&bcsp->tbcsp);
spin_unlock_irqrestore(&bcsp->unack.lock, flags);
if (i != pkts_to_be_removed)
BT_ERR("Removed only %u out of %u pkts", i, pkts_to_be_removed);
}
/* Handle BCSP link-establishment packets. When we
* detect a "sync" packet, symptom that the BT module has reset,
* we do nothing :) (yet)
*/
static void bcsp_handle_le_pkt(struct hci_uart *hu)
{
struct bcsp_struct *bcsp = hu->priv;
u8 conf_pkt[4] = { 0xad, 0xef, 0xac, 0xed };
u8 conf_rsp_pkt[4] = { 0xde, 0xad, 0xd0, 0xd0 };
u8 sync_pkt[4] = { 0xda, 0xdc, 0xed, 0xed };
/* spot "conf" pkts and reply with a "conf rsp" pkt */
if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&
!memcmp(&bcsp->rx_skb->data[4], conf_pkt, 4)) {
struct sk_buff *nskb = alloc_skb(4, GFP_ATOMIC);
BT_DBG("Found a LE conf pkt");
if (!nskb)
return;
skb_put_data(nskb, conf_rsp_pkt, 4);
hci_skb_pkt_type(nskb) = BCSP_LE_PKT;
skb_queue_head(&bcsp->unrel, nskb);
hci_uart_tx_wakeup(hu);
}
/* Spot "sync" pkts. If we find one...disaster! */
else if (bcsp->rx_skb->data[1] >> 4 == 4 && bcsp->rx_skb->data[2] == 0 &&
!memcmp(&bcsp->rx_skb->data[4], sync_pkt, 4)) {
BT_ERR("Found a LE sync pkt, card has reset");
}
}
static inline void bcsp_unslip_one_byte(struct bcsp_struct *bcsp, unsigned char byte)
{
const u8 c0 = 0xc0, db = 0xdb;
switch (bcsp->rx_esc_state) {
case BCSP_ESCSTATE_NOESC:
switch (byte) {
case 0xdb:
bcsp->rx_esc_state = BCSP_ESCSTATE_ESC;
break;
default:
skb_put_data(bcsp->rx_skb, &byte, 1);
if ((bcsp->rx_skb->data[0] & 0x40) != 0 &&
bcsp->rx_state != BCSP_W4_CRC)
bcsp_crc_update(&bcsp->message_crc, byte);
bcsp->rx_count--;
}
break;
case BCSP_ESCSTATE_ESC:
switch (byte) {
case 0xdc:
skb_put_data(bcsp->rx_skb, &c0, 1);
if ((bcsp->rx_skb->data[0] & 0x40) != 0 &&
bcsp->rx_state != BCSP_W4_CRC)
bcsp_crc_update(&bcsp->message_crc, 0xc0);
bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
bcsp->rx_count--;
break;
case 0xdd:
skb_put_data(bcsp->rx_skb, &db, 1);
if ((bcsp->rx_skb->data[0] & 0x40) != 0 &&
bcsp->rx_state != BCSP_W4_CRC)
bcsp_crc_update(&bcsp->message_crc, 0xdb);
bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
bcsp->rx_count--;
break;
default:
BT_ERR("Invalid byte %02x after esc byte", byte);
kfree_skb(bcsp->rx_skb);
bcsp->rx_skb = NULL;
bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
bcsp->rx_count = 0;
}
}
}
static void bcsp_complete_rx_pkt(struct hci_uart *hu)
{
struct bcsp_struct *bcsp = hu->priv;
int pass_up = 0;
if (bcsp->rx_skb->data[0] & 0x80) { /* reliable pkt */
BT_DBG("Received seqno %u from card", bcsp->rxseq_txack);
/* check the rx sequence number is as expected */
if ((bcsp->rx_skb->data[0] & 0x07) == bcsp->rxseq_txack) {
bcsp->rxseq_txack++;
bcsp->rxseq_txack %= 0x8;
} else {
/* handle re-transmitted packet or
* when packet was missed
*/
BT_ERR("Out-of-order packet arrived, got %u expected %u",
bcsp->rx_skb->data[0] & 0x07, bcsp->rxseq_txack);
/* do not process out-of-order packet payload */
pass_up = 2;
}
/* send current txack value to all received reliable packets */
bcsp->txack_req = 1;
/* If needed, transmit an ack pkt */
hci_uart_tx_wakeup(hu);
}
bcsp->rxack = (bcsp->rx_skb->data[0] >> 3) & 0x07;
BT_DBG("Request for pkt %u from card", bcsp->rxack);
/* handle received ACK indications,
* including those from out-of-order packets
*/
bcsp_pkt_cull(bcsp);
if (pass_up != 2) {
if ((bcsp->rx_skb->data[1] & 0x0f) == 6 &&
(bcsp->rx_skb->data[0] & 0x80)) {
hci_skb_pkt_type(bcsp->rx_skb) = HCI_ACLDATA_PKT;
pass_up = 1;
} else if ((bcsp->rx_skb->data[1] & 0x0f) == 5 &&
(bcsp->rx_skb->data[0] & 0x80)) {
hci_skb_pkt_type(bcsp->rx_skb) = HCI_EVENT_PKT;
pass_up = 1;
} else if ((bcsp->rx_skb->data[1] & 0x0f) == 7) {
hci_skb_pkt_type(bcsp->rx_skb) = HCI_SCODATA_PKT;
pass_up = 1;
} else if ((bcsp->rx_skb->data[1] & 0x0f) == 1 &&
!(bcsp->rx_skb->data[0] & 0x80)) {
bcsp_handle_le_pkt(hu);
pass_up = 0;
} else {
pass_up = 0;
}
}
if (pass_up == 0) {
struct hci_event_hdr hdr;
u8 desc = (bcsp->rx_skb->data[1] & 0x0f);
if (desc != 0 && desc != 1) {
if (hciextn) {
desc |= 0xc0;
skb_pull(bcsp->rx_skb, 4);
memcpy(skb_push(bcsp->rx_skb, 1), &desc, 1);
hdr.evt = 0xff;
hdr.plen = bcsp->rx_skb->len;
memcpy(skb_push(bcsp->rx_skb, HCI_EVENT_HDR_SIZE), &hdr, HCI_EVENT_HDR_SIZE);
hci_skb_pkt_type(bcsp->rx_skb) = HCI_EVENT_PKT;
hci_recv_frame(hu->hdev, bcsp->rx_skb);
} else {
BT_ERR("Packet for unknown channel (%u %s)",
bcsp->rx_skb->data[1] & 0x0f,
bcsp->rx_skb->data[0] & 0x80 ?
"reliable" : "unreliable");
kfree_skb(bcsp->rx_skb);
}
} else
kfree_skb(bcsp->rx_skb);
} else if (pass_up == 1) {
/* Pull out BCSP hdr */
skb_pull(bcsp->rx_skb, 4);
hci_recv_frame(hu->hdev, bcsp->rx_skb);
} else {
/* ignore packet payload of already ACKed re-transmitted
* packets or when a packet was missed in the BCSP window
*/
kfree_skb(bcsp->rx_skb);
}
bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
bcsp->rx_skb = NULL;
}
static u16 bscp_get_crc(struct bcsp_struct *bcsp)
{
return get_unaligned_be16(&bcsp->rx_skb->data[bcsp->rx_skb->len - 2]);
}
/* Recv data */
static int bcsp_recv(struct hci_uart *hu, const void *data, int count)
{
struct bcsp_struct *bcsp = hu->priv;
const unsigned char *ptr;
BT_DBG("hu %p count %d rx_state %d rx_count %ld",
hu, count, bcsp->rx_state, bcsp->rx_count);
ptr = data;
while (count) {
if (bcsp->rx_count) {
if (*ptr == 0xc0) {
BT_ERR("Short BCSP packet");
kfree_skb(bcsp->rx_skb);
bcsp->rx_state = BCSP_W4_PKT_START;
bcsp->rx_count = 0;
} else
bcsp_unslip_one_byte(bcsp, *ptr);
ptr++; count--;
continue;
}
switch (bcsp->rx_state) {
case BCSP_W4_BCSP_HDR:
if ((0xff & (u8)~(bcsp->rx_skb->data[0] + bcsp->rx_skb->data[1] +
bcsp->rx_skb->data[2])) != bcsp->rx_skb->data[3]) {
BT_ERR("Error in BCSP hdr checksum");
kfree_skb(bcsp->rx_skb);
bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
bcsp->rx_count = 0;
continue;
}
bcsp->rx_state = BCSP_W4_DATA;
bcsp->rx_count = (bcsp->rx_skb->data[1] >> 4) +
(bcsp->rx_skb->data[2] << 4); /* May be 0 */
continue;
case BCSP_W4_DATA:
if (bcsp->rx_skb->data[0] & 0x40) { /* pkt with crc */
bcsp->rx_state = BCSP_W4_CRC;
bcsp->rx_count = 2;
} else
bcsp_complete_rx_pkt(hu);
continue;
case BCSP_W4_CRC:
if (bitrev16(bcsp->message_crc) != bscp_get_crc(bcsp)) {
BT_ERR("Checksum failed: computed %04x received %04x",
bitrev16(bcsp->message_crc),
bscp_get_crc(bcsp));
kfree_skb(bcsp->rx_skb);
bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
bcsp->rx_count = 0;
continue;
}
skb_trim(bcsp->rx_skb, bcsp->rx_skb->len - 2);
bcsp_complete_rx_pkt(hu);
continue;
case BCSP_W4_PKT_DELIMITER:
switch (*ptr) {
case 0xc0:
bcsp->rx_state = BCSP_W4_PKT_START;
break;
default:
/*BT_ERR("Ignoring byte %02x", *ptr);*/
break;
}
ptr++; count--;
break;
case BCSP_W4_PKT_START:
switch (*ptr) {
case 0xc0:
ptr++; count--;
break;
default:
bcsp->rx_state = BCSP_W4_BCSP_HDR;
bcsp->rx_count = 4;
bcsp->rx_esc_state = BCSP_ESCSTATE_NOESC;
BCSP_CRC_INIT(bcsp->message_crc);
/* Do not increment ptr or decrement count
* Allocate packet. Max len of a BCSP pkt=
* 0xFFF (payload) +4 (header) +2 (crc)
*/
bcsp->rx_skb = bt_skb_alloc(0x1005, GFP_ATOMIC);
if (!bcsp->rx_skb) {
BT_ERR("Can't allocate mem for new packet");
bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
bcsp->rx_count = 0;
return 0;
}
break;
}
break;
}
}
return count;
}
/* Arrange to retransmit all messages in the relq. */
static void bcsp_timed_event(struct timer_list *t)
{
struct bcsp_struct *bcsp = from_timer(bcsp, t, tbcsp);
struct hci_uart *hu = bcsp->hu;
struct sk_buff *skb;
unsigned long flags;
BT_DBG("hu %p retransmitting %u pkts", hu, bcsp->unack.qlen);
spin_lock_irqsave_nested(&bcsp->unack.lock, flags, SINGLE_DEPTH_NESTING);
while ((skb = __skb_dequeue_tail(&bcsp->unack)) != NULL) {
bcsp->msgq_txseq = (bcsp->msgq_txseq - 1) & 0x07;
skb_queue_head(&bcsp->rel, skb);
}
spin_unlock_irqrestore(&bcsp->unack.lock, flags);
hci_uart_tx_wakeup(hu);
}
static int bcsp_open(struct hci_uart *hu)
{
struct bcsp_struct *bcsp;
BT_DBG("hu %p", hu);
bcsp = kzalloc(sizeof(*bcsp), GFP_KERNEL);
if (!bcsp)
return -ENOMEM;
hu->priv = bcsp;
bcsp->hu = hu;
skb_queue_head_init(&bcsp->unack);
skb_queue_head_init(&bcsp->rel);
skb_queue_head_init(&bcsp->unrel);
timer_setup(&bcsp->tbcsp, bcsp_timed_event, 0);
bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
if (txcrc)
bcsp->use_crc = 1;
return 0;
}
static int bcsp_close(struct hci_uart *hu)
{
struct bcsp_struct *bcsp = hu->priv;
del_timer_sync(&bcsp->tbcsp);
hu->priv = NULL;
BT_DBG("hu %p", hu);
skb_queue_purge(&bcsp->unack);
skb_queue_purge(&bcsp->rel);
skb_queue_purge(&bcsp->unrel);
if (bcsp->rx_skb) {
kfree_skb(bcsp->rx_skb);
bcsp->rx_skb = NULL;
}
kfree(bcsp);
return 0;
}
static const struct hci_uart_proto bcsp = {
.id = HCI_UART_BCSP,
.name = "BCSP",
.open = bcsp_open,
.close = bcsp_close,
.enqueue = bcsp_enqueue,
.dequeue = bcsp_dequeue,
.recv = bcsp_recv,
.flush = bcsp_flush
};
int __init bcsp_init(void)
{
return hci_uart_register_proto(&bcsp);
}
int __exit bcsp_deinit(void)
{
return hci_uart_unregister_proto(&bcsp);
}
module_param(txcrc, bool, 0644);
MODULE_PARM_DESC(txcrc, "Transmit CRC with every BCSP packet");
module_param(hciextn, bool, 0644);
MODULE_PARM_DESC(hciextn, "Convert HCI Extensions into BCSP packets");