/*
*
* Bluetooth HCI UART driver
*
* Copyright (C) 2000-2001 Qualcomm Incorporated
* Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com>
* Copyright (C) 2004-2005 Marcel Holtmann <marcel@holtmann.org>
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/sched.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 <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include "hci_uart.h"
#ifndef CONFIG_BT_HCIUART_DEBUG
#undef BT_DBG
#define BT_DBG( A... )
#endif
#define VERSION "1.2"
struct h4_struct {
unsigned long rx_state;
unsigned long rx_count;
struct sk_buff *rx_skb;
struct sk_buff_head txq;
};
/* H4 receiver States */
#define H4_W4_PACKET_TYPE 0
#define H4_W4_EVENT_HDR 1
#define H4_W4_ACL_HDR 2
#define H4_W4_SCO_HDR 3
#define H4_W4_DATA 4
/* Initialize protocol */
static int h4_open(struct hci_uart *hu)
{
struct h4_struct *h4;
BT_DBG("hu %p", hu);
h4 = kmalloc(sizeof(*h4), GFP_ATOMIC);
if (!h4)
return -ENOMEM;
memset(h4, 0, sizeof(*h4));
skb_queue_head_init(&h4->txq);
hu->priv = h4;
return 0;
}
/* Flush protocol data */
static int h4_flush(struct hci_uart *hu)
{
struct h4_struct *h4 = hu->priv;
BT_DBG("hu %p", hu);
skb_queue_purge(&h4->txq);
return 0;
}
/* Close protocol */
static int h4_close(struct hci_uart *hu)
{
struct h4_struct *h4 = hu->priv;
hu->priv = NULL;
BT_DBG("hu %p", hu);
skb_queue_purge(&h4->txq);
if (h4->rx_skb)
kfree_skb(h4->rx_skb);
hu->priv = NULL;
kfree(h4);
return 0;
}
/* Enqueue frame for transmittion (padding, crc, etc) */
static int h4_enqueue(struct hci_uart *hu, struct sk_buff *skb)
{
struct h4_struct *h4 = hu->priv;
BT_DBG("hu %p skb %p", hu, skb);
/* Prepend skb with frame type */
memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
skb_queue_tail(&h4->txq, skb);
return 0;
}
static inline int h4_check_data_len(struct h4_struct *h4, int len)
{
register int room = skb_tailroom(h4->rx_skb);
BT_DBG("len %d room %d", len, room);
if (!len) {
hci_recv_frame(h4->rx_skb);
} else if (len > room) {
BT_ERR("Data length is too large");
kfree_skb(h4->rx_skb);
} else {
h4->rx_state = H4_W4_DATA;
h4->rx_count = len;
return len;
}
h4->rx_state = H4_W4_PACKET_TYPE;
h4->rx_skb = NULL;
h4->rx_count = 0;
return 0;
}
/* Recv data */
static int h4_recv(struct hci_uart *hu, void *data, int count)
{
struct h4_struct *h4 = hu->priv;
register char *ptr;
struct hci_event_hdr *eh;
struct hci_acl_hdr *ah;
struct hci_sco_hdr *sh;
register int len, type, dlen;
BT_DBG("hu %p count %d rx_state %ld rx_count %ld",
hu, count, h4->rx_state, h4->rx_count);
ptr = data;
while (count) {
if (h4->rx_count) {
len = min_t(unsigned int, h4->rx_count, count);
memcpy(skb_put(h4->rx_skb, len), ptr, len);
h4->rx_count -= len; count -= len; ptr += len;
if (h4->rx_count)
continue;
switch (h4->rx_state) {
case H4_W4_DATA:
BT_DBG("Complete data");
hci_recv_frame(h4->rx_skb);
h4->rx_state = H4_W4_PACKET_TYPE;
h4->rx_skb = NULL;
continue;
case H4_W4_EVENT_HDR:
eh = (struct hci_event_hdr *) h4->rx_skb->data;
BT_DBG("Event header: evt 0x%2.2x plen %d", eh->evt, eh->plen);
h4_check_data_len(h4, eh->plen);
continue;
case H4_W4_ACL_HDR:
ah = (struct hci_acl_hdr *) h4->rx_skb->data;
dlen = __le16_to_cpu(ah->dlen);
BT_DBG("ACL header: dlen %d", dlen);
h4_check_data_len(h4, dlen);
continue;
case H4_W4_SCO_HDR:
sh = (struct hci_sco_hdr *) h4->rx_skb->data;
BT_DBG("SCO header: dlen %d", sh->dlen);
h4_check_data_len(h4, sh->dlen);
continue;
}
}
/* H4_W4_PACKET_TYPE */
switch (*ptr) {
case HCI_EVENT_PKT:
BT_DBG("Event packet");
h4->rx_state = H4_W4_EVENT_HDR;
h4->rx_count = HCI_EVENT_HDR_SIZE;
type = HCI_EVENT_PKT;
break;
case HCI_ACLDATA_PKT:
BT_DBG("ACL packet");
h4->rx_state = H4_W4_ACL_HDR;
h4->rx_count = HCI_ACL_HDR_SIZE;
type = HCI_ACLDATA_PKT;
break;
case HCI_SCODATA_PKT:
BT_DBG("SCO packet");
h4->rx_state = H4_W4_SCO_HDR;
h4->rx_count = HCI_SCO_HDR_SIZE;
type = HCI_SCODATA_PKT;
break;
default:
BT_ERR("Unknown HCI packet type %2.2x", (__u8)*ptr);
hu->hdev->stat.err_rx++;
ptr++; count--;
continue;
};
ptr++; count--;
/* Allocate packet */
h4->rx_skb = bt_skb_alloc(HCI_MAX_FRAME_SIZE, GFP_ATOMIC);
if (!h4->rx_skb) {
BT_ERR("Can't allocate mem for new packet");
h4->rx_state = H4_W4_PACKET_TYPE;
h4->rx_count = 0;
return 0;
}
h4->rx_skb->dev = (void *) hu->hdev;
bt_cb(h4->rx_skb)->pkt_type = type;
}
return count;
}
static struct sk_buff *h4_dequeue(struct hci_uart *hu)
{
struct h4_struct *h4 = hu->priv;
return skb_dequeue(&h4->txq);
}
static struct hci_uart_proto h4p = {
.id = HCI_UART_H4,
.open = h4_open,
.close = h4_close,
.recv = h4_recv,
.enqueue = h4_enqueue,
.dequeue = h4_dequeue,
.flush = h4_flush,
};
int h4_init(void)
{
int err = hci_uart_register_proto(&h4p);
if (!err)
BT_INFO("HCI H4 protocol initialized");
else
BT_ERR("HCI H4 protocol registration failed");
return err;
}
int h4_deinit(void)
{
return hci_uart_unregister_proto(&h4p);
}
