avr32: at32ap700x: setup DMA for ABDAC in the machine code
[linux-2.6] / drivers / bluetooth / hci_h4.c
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 */
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_ATOMIC);
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 */
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 */
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) */
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
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 */
152 static int h4_recv(struct hci_uart *hu, void *data, int count)
153 {
154         struct h4_struct *h4 = hu->priv;
155         register char *ptr;
156         struct hci_event_hdr *eh;
157         struct hci_acl_hdr   *ah;
158         struct hci_sco_hdr   *sh;
159         register int len, type, dlen;
160
161         BT_DBG("hu %p count %d rx_state %ld rx_count %ld", 
162                         hu, count, h4->rx_state, h4->rx_count);
163
164         ptr = data;
165         while (count) {
166                 if (h4->rx_count) {
167                         len = min_t(unsigned int, h4->rx_count, count);
168                         memcpy(skb_put(h4->rx_skb, len), ptr, len);
169                         h4->rx_count -= len; count -= len; ptr += len;
170
171                         if (h4->rx_count)
172                                 continue;
173
174                         switch (h4->rx_state) {
175                         case H4_W4_DATA:
176                                 BT_DBG("Complete data");
177
178                                 hci_recv_frame(h4->rx_skb);
179
180                                 h4->rx_state = H4_W4_PACKET_TYPE;
181                                 h4->rx_skb = NULL;
182                                 continue;
183
184                         case H4_W4_EVENT_HDR:
185                                 eh = hci_event_hdr(h4->rx_skb);
186
187                                 BT_DBG("Event header: evt 0x%2.2x plen %d", eh->evt, eh->plen);
188
189                                 h4_check_data_len(h4, eh->plen);
190                                 continue;
191
192                         case H4_W4_ACL_HDR:
193                                 ah = hci_acl_hdr(h4->rx_skb);
194                                 dlen = __le16_to_cpu(ah->dlen);
195
196                                 BT_DBG("ACL header: dlen %d", dlen);
197
198                                 h4_check_data_len(h4, dlen);
199                                 continue;
200
201                         case H4_W4_SCO_HDR:
202                                 sh = hci_sco_hdr(h4->rx_skb);
203
204                                 BT_DBG("SCO header: dlen %d", sh->dlen);
205
206                                 h4_check_data_len(h4, sh->dlen);
207                                 continue;
208                         }
209                 }
210
211                 /* H4_W4_PACKET_TYPE */
212                 switch (*ptr) {
213                 case HCI_EVENT_PKT:
214                         BT_DBG("Event packet");
215                         h4->rx_state = H4_W4_EVENT_HDR;
216                         h4->rx_count = HCI_EVENT_HDR_SIZE;
217                         type = HCI_EVENT_PKT;
218                         break;
219
220                 case HCI_ACLDATA_PKT:
221                         BT_DBG("ACL packet");
222                         h4->rx_state = H4_W4_ACL_HDR;
223                         h4->rx_count = HCI_ACL_HDR_SIZE;
224                         type = HCI_ACLDATA_PKT;
225                         break;
226
227                 case HCI_SCODATA_PKT:
228                         BT_DBG("SCO packet");
229                         h4->rx_state = H4_W4_SCO_HDR;
230                         h4->rx_count = HCI_SCO_HDR_SIZE;
231                         type = HCI_SCODATA_PKT;
232                         break;
233
234                 default:
235                         BT_ERR("Unknown HCI packet type %2.2x", (__u8)*ptr);
236                         hu->hdev->stat.err_rx++;
237                         ptr++; count--;
238                         continue;
239                 };
240
241                 ptr++; count--;
242
243                 /* Allocate packet */
244                 h4->rx_skb = bt_skb_alloc(HCI_MAX_FRAME_SIZE, GFP_ATOMIC);
245                 if (!h4->rx_skb) {
246                         BT_ERR("Can't allocate mem for new packet");
247                         h4->rx_state = H4_W4_PACKET_TYPE;
248                         h4->rx_count = 0;
249                         return 0;
250                 }
251
252                 h4->rx_skb->dev = (void *) hu->hdev;
253                 bt_cb(h4->rx_skb)->pkt_type = type;
254         }
255
256         return count;
257 }
258
259 static struct sk_buff *h4_dequeue(struct hci_uart *hu)
260 {
261         struct h4_struct *h4 = hu->priv;
262         return skb_dequeue(&h4->txq);
263 }
264
265 static struct hci_uart_proto h4p = {
266         .id             = HCI_UART_H4,
267         .open           = h4_open,
268         .close          = h4_close,
269         .recv           = h4_recv,
270         .enqueue        = h4_enqueue,
271         .dequeue        = h4_dequeue,
272         .flush          = h4_flush,
273 };
274
275 int h4_init(void)
276 {
277         int err = hci_uart_register_proto(&h4p);
278
279         if (!err)
280                 BT_INFO("HCI H4 protocol initialized");
281         else
282                 BT_ERR("HCI H4 protocol registration failed");
283
284         return err;
285 }
286
287 int h4_deinit(void)
288 {
289         return hci_uart_unregister_proto(&h4p);
290 }