0bbefba6469cee659e7b114e961a677e3fa65fa0
[pandora-kernel.git] / drivers / bluetooth / hci_vhci.c
1 /*
2  *
3  *  Bluetooth virtual HCI driver
4  *
5  *  Copyright (C) 2000-2001  Qualcomm Incorporated
6  *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
7  *  Copyright (C) 2004-2006  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/slab.h>
31 #include <linux/smp_lock.h>
32 #include <linux/types.h>
33 #include <linux/errno.h>
34 #include <linux/sched.h>
35 #include <linux/poll.h>
36
37 #include <linux/skbuff.h>
38 #include <linux/miscdevice.h>
39
40 #include <net/bluetooth/bluetooth.h>
41 #include <net/bluetooth/hci_core.h>
42
43 #define VERSION "1.2"
44
45 static int minor = MISC_DYNAMIC_MINOR;
46
47 struct vhci_data {
48         struct hci_dev *hdev;
49
50         unsigned long flags;
51
52         wait_queue_head_t read_wait;
53         struct sk_buff_head readq;
54
55         struct fasync_struct *fasync;
56 };
57
58 #define VHCI_FASYNC     0x0010
59
60 static struct miscdevice vhci_miscdev;
61
62 static int vhci_open_dev(struct hci_dev *hdev)
63 {
64         set_bit(HCI_RUNNING, &hdev->flags);
65
66         return 0;
67 }
68
69 static int vhci_close_dev(struct hci_dev *hdev)
70 {
71         struct vhci_data *data = hdev->driver_data;
72
73         if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
74                 return 0;
75
76         skb_queue_purge(&data->readq);
77
78         return 0;
79 }
80
81 static int vhci_flush(struct hci_dev *hdev)
82 {
83         struct vhci_data *data = hdev->driver_data;
84
85         skb_queue_purge(&data->readq);
86
87         return 0;
88 }
89
90 static int vhci_send_frame(struct sk_buff *skb)
91 {
92         struct hci_dev* hdev = (struct hci_dev *) skb->dev;
93         struct vhci_data *data;
94
95         if (!hdev) {
96                 BT_ERR("Frame for unknown HCI device (hdev=NULL)");
97                 return -ENODEV;
98         }
99
100         if (!test_bit(HCI_RUNNING, &hdev->flags))
101                 return -EBUSY;
102
103         data = hdev->driver_data;
104
105         memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
106         skb_queue_tail(&data->readq, skb);
107
108         if (data->flags & VHCI_FASYNC)
109                 kill_fasync(&data->fasync, SIGIO, POLL_IN);
110
111         wake_up_interruptible(&data->read_wait);
112
113         return 0;
114 }
115
116 static void vhci_destruct(struct hci_dev *hdev)
117 {
118         kfree(hdev->driver_data);
119 }
120
121 static inline ssize_t vhci_get_user(struct vhci_data *data,
122                                         const char __user *buf, size_t count)
123 {
124         struct sk_buff *skb;
125
126         if (count > HCI_MAX_FRAME_SIZE)
127                 return -EINVAL;
128
129         skb = bt_skb_alloc(count, GFP_KERNEL);
130         if (!skb)
131                 return -ENOMEM;
132
133         if (copy_from_user(skb_put(skb, count), buf, count)) {
134                 kfree_skb(skb);
135                 return -EFAULT;
136         }
137
138         skb->dev = (void *) data->hdev;
139         bt_cb(skb)->pkt_type = *((__u8 *) skb->data);
140         skb_pull(skb, 1);
141
142         hci_recv_frame(skb);
143
144         return count;
145 }
146
147 static inline ssize_t vhci_put_user(struct vhci_data *data,
148                         struct sk_buff *skb, char __user *buf, int count)
149 {
150         char __user *ptr = buf;
151         int len, total = 0;
152
153         len = min_t(unsigned int, skb->len, count);
154
155         if (copy_to_user(ptr, skb->data, len))
156                 return -EFAULT;
157
158         total += len;
159
160         data->hdev->stat.byte_tx += len;
161
162         switch (bt_cb(skb)->pkt_type) {
163         case HCI_COMMAND_PKT:
164                 data->hdev->stat.cmd_tx++;
165                 break;
166
167         case HCI_ACLDATA_PKT:
168                 data->hdev->stat.acl_tx++;
169                 break;
170
171         case HCI_SCODATA_PKT:
172                 data->hdev->stat.cmd_tx++;
173                 break;
174         };
175
176         return total;
177 }
178
179 static ssize_t vhci_read(struct file *file,
180                                 char __user *buf, size_t count, loff_t *pos)
181 {
182         DECLARE_WAITQUEUE(wait, current);
183         struct vhci_data *data = file->private_data;
184         struct sk_buff *skb;
185         ssize_t ret = 0;
186
187         add_wait_queue(&data->read_wait, &wait);
188         while (count) {
189                 set_current_state(TASK_INTERRUPTIBLE);
190
191                 skb = skb_dequeue(&data->readq);
192                 if (!skb) {
193                         if (file->f_flags & O_NONBLOCK) {
194                                 ret = -EAGAIN;
195                                 break;
196                         }
197
198                         if (signal_pending(current)) {
199                                 ret = -ERESTARTSYS;
200                                 break;
201                         }
202
203                         schedule();
204                         continue;
205                 }
206
207                 if (access_ok(VERIFY_WRITE, buf, count))
208                         ret = vhci_put_user(data, skb, buf, count);
209                 else
210                         ret = -EFAULT;
211
212                 kfree_skb(skb);
213                 break;
214         }
215         set_current_state(TASK_RUNNING);
216         remove_wait_queue(&data->read_wait, &wait);
217
218         return ret;
219 }
220
221 static ssize_t vhci_write(struct file *file,
222                         const char __user *buf, size_t count, loff_t *pos)
223 {
224         struct vhci_data *data = file->private_data;
225
226         if (!access_ok(VERIFY_READ, buf, count))
227                 return -EFAULT;
228
229         return vhci_get_user(data, buf, count);
230 }
231
232 static unsigned int vhci_poll(struct file *file, poll_table *wait)
233 {
234         struct vhci_data *data = file->private_data;
235
236         poll_wait(file, &data->read_wait, wait);
237
238         if (!skb_queue_empty(&data->readq))
239                 return POLLIN | POLLRDNORM;
240
241         return POLLOUT | POLLWRNORM;
242 }
243
244 static int vhci_ioctl(struct inode *inode, struct file *file,
245                                         unsigned int cmd, unsigned long arg)
246 {
247         return -EINVAL;
248 }
249
250 static int vhci_open(struct inode *inode, struct file *file)
251 {
252         struct vhci_data *data;
253         struct hci_dev *hdev;
254
255         data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL);
256         if (!data)
257                 return -ENOMEM;
258
259         skb_queue_head_init(&data->readq);
260         init_waitqueue_head(&data->read_wait);
261
262         lock_kernel();
263         hdev = hci_alloc_dev();
264         if (!hdev) {
265                 kfree(data);
266                 unlock_kernel();
267                 return -ENOMEM;
268         }
269
270         data->hdev = hdev;
271
272         hdev->type = HCI_VIRTUAL;
273         hdev->driver_data = data;
274
275         hdev->open     = vhci_open_dev;
276         hdev->close    = vhci_close_dev;
277         hdev->flush    = vhci_flush;
278         hdev->send     = vhci_send_frame;
279         hdev->destruct = vhci_destruct;
280
281         hdev->owner = THIS_MODULE;
282
283         if (hci_register_dev(hdev) < 0) {
284                 BT_ERR("Can't register HCI device");
285                 kfree(data);
286                 hci_free_dev(hdev);
287                 unlock_kernel();
288                 return -EBUSY;
289         }
290
291         file->private_data = data;
292         unlock_kernel();
293
294         return nonseekable_open(inode, file);
295 }
296
297 static int vhci_release(struct inode *inode, struct file *file)
298 {
299         struct vhci_data *data = file->private_data;
300         struct hci_dev *hdev = data->hdev;
301
302         if (hci_unregister_dev(hdev) < 0) {
303                 BT_ERR("Can't unregister HCI device %s", hdev->name);
304         }
305
306         hci_free_dev(hdev);
307
308         file->private_data = NULL;
309
310         return 0;
311 }
312
313 static int vhci_fasync(int fd, struct file *file, int on)
314 {
315         struct vhci_data *data = file->private_data;
316         int err = 0;
317
318         lock_kernel();
319         err = fasync_helper(fd, file, on, &data->fasync);
320         if (err < 0)
321                 goto out;
322
323         if (on)
324                 data->flags |= VHCI_FASYNC;
325         else
326                 data->flags &= ~VHCI_FASYNC;
327
328 out:
329         unlock_kernel();
330         return err;
331 }
332
333 static const struct file_operations vhci_fops = {
334         .owner          = THIS_MODULE,
335         .read           = vhci_read,
336         .write          = vhci_write,
337         .poll           = vhci_poll,
338         .ioctl          = vhci_ioctl,
339         .open           = vhci_open,
340         .release        = vhci_release,
341         .fasync         = vhci_fasync,
342 };
343
344 static struct miscdevice vhci_miscdev= {
345         .name           = "vhci",
346         .fops           = &vhci_fops,
347 };
348
349 static int __init vhci_init(void)
350 {
351         BT_INFO("Virtual HCI driver ver %s", VERSION);
352
353         vhci_miscdev.minor = minor;
354
355         if (misc_register(&vhci_miscdev) < 0) {
356                 BT_ERR("Can't register misc device with minor %d", minor);
357                 return -EIO;
358         }
359
360         return 0;
361 }
362
363 static void __exit vhci_exit(void)
364 {
365         if (misc_deregister(&vhci_miscdev) < 0)
366                 BT_ERR("Can't unregister misc device with minor %d", minor);
367 }
368
369 module_init(vhci_init);
370 module_exit(vhci_exit);
371
372 module_param(minor, int, 0444);
373 MODULE_PARM_DESC(minor, "Miscellaneous minor device number");
374
375 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
376 MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION);
377 MODULE_VERSION(VERSION);
378 MODULE_LICENSE("GPL");