1 /*
2 *
3 * Bluetooth HCI UART driver
4 *
5 * Copyright (C) 2000-2001 Qualcomm Incorporated
6 * Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com>
7 * Copyright (C) 2004-2005 Marcel Holtmann <marcel@holtmann.org>
8 *
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 *
24 */
25
26 #include <linux/module.h>
27
28 #include <linux/kernel.h>
29 #include <linux/init.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>
35
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>
43
44 #include <net/bluetooth/bluetooth.h>
45 #include <net/bluetooth/hci_core.h>
46
47 #include "hci_uart.h"
48
49 #define VERSION "1.2"
50
51 struct h4_struct {
52 unsigned long rx_state;
53 unsigned long rx_count;
54 struct sk_buff *rx_skb;
55 struct sk_buff_head txq;
56 };
57
58 /* H4 receiver States */
59 #define H4_W4_PACKET_TYPE 0
60 #define H4_W4_EVENT_HDR 1
61 #define H4_W4_ACL_HDR 2
62 #define H4_W4_SCO_HDR 3
63 #define H4_W4_DATA 4
64
65 /* Initialize protocol */
h4_open(struct hci_uart * hu)66 static int h4_open(struct hci_uart *hu)
67 {
68 struct h4_struct *h4;
69
70 BT_DBG("hu %p", hu);
71
72 h4 = kzalloc(sizeof(*h4), GFP_KERNEL);
73 if (!h4)
74 return -ENOMEM;
75
76 skb_queue_head_init(&h4->txq);
77
78 hu->priv = h4;
79 return 0;
80 }
81
82 /* Flush protocol data */
h4_flush(struct hci_uart * hu)83 static int h4_flush(struct hci_uart *hu)
84 {
85 struct h4_struct *h4 = hu->priv;
86
87 BT_DBG("hu %p", hu);
88
89 skb_queue_purge(&h4->txq);
90
91 return 0;
92 }
93
94 /* Close protocol */
h4_close(struct hci_uart * hu)95 static int h4_close(struct hci_uart *hu)
96 {
97 struct h4_struct *h4 = hu->priv;
98
99 hu->priv = NULL;
100
101 BT_DBG("hu %p", hu);
102
103 skb_queue_purge(&h4->txq);
104
105 kfree_skb(h4->rx_skb);
106
107 hu->priv = NULL;
108 kfree(h4);
109
110 return 0;
111 }
112
113 /* Enqueue frame for transmittion (padding, crc, etc) */
h4_enqueue(struct hci_uart * hu,struct sk_buff * skb)114 static int h4_enqueue(struct hci_uart *hu, struct sk_buff *skb)
115 {
116 struct h4_struct *h4 = hu->priv;
117
118 BT_DBG("hu %p skb %p", hu, skb);
119
120 /* Prepend skb with frame type */
121 memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
122 skb_queue_tail(&h4->txq, skb);
123
124 return 0;
125 }
126
h4_check_data_len(struct h4_struct * h4,int len)127 static inline int h4_check_data_len(struct h4_struct *h4, int len)
128 {
129 register int room = skb_tailroom(h4->rx_skb);
130
131 BT_DBG("len %d room %d", len, room);
132
133 if (!len) {
134 hci_recv_frame(h4->rx_skb);
135 } else if (len > room) {
136 BT_ERR("Data length is too large");
137 kfree_skb(h4->rx_skb);
138 } else {
139 h4->rx_state = H4_W4_DATA;
140 h4->rx_count = len;
141 return len;
142 }
143
144 h4->rx_state = H4_W4_PACKET_TYPE;
145 h4->rx_skb = NULL;
146 h4->rx_count = 0;
147
148 return 0;
149 }
150
151 /* Recv data */
h4_recv(struct hci_uart * hu,void * data,int count)152 static int h4_recv(struct hci_uart *hu, void *data, int count)
153 {
154 int ret;
155
156 ret = hci_recv_stream_fragment(hu->hdev, data, count);
157 if (ret < 0) {
158 BT_ERR("Frame Reassembly Failed");
159 return ret;
160 }
161
162 return count;
163 }
164
h4_dequeue(struct hci_uart * hu)165 static struct sk_buff *h4_dequeue(struct hci_uart *hu)
166 {
167 struct h4_struct *h4 = hu->priv;
168 return skb_dequeue(&h4->txq);
169 }
170
171 static struct hci_uart_proto h4p = {
172 .id = HCI_UART_H4,
173 .open = h4_open,
174 .close = h4_close,
175 .recv = h4_recv,
176 .enqueue = h4_enqueue,
177 .dequeue = h4_dequeue,
178 .flush = h4_flush,
179 };
180
h4_init(void)181 int __init h4_init(void)
182 {
183 int err = hci_uart_register_proto(&h4p);
184
185 if (!err)
186 BT_INFO("HCI H4 protocol initialized");
187 else
188 BT_ERR("HCI H4 protocol registration failed");
189
190 return err;
191 }
192
h4_deinit(void)193 int __exit h4_deinit(void)
194 {
195 return hci_uart_unregister_proto(&h4p);
196 }
197