1 /*
2 * dvbdev.c
3 *
4 * Copyright (C) 2000 Ralph Metzler <ralph@convergence.de>
5 * & Marcus Metzler <marcus@convergence.de>
6 * for convergence integrated media GmbH
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public License
10 * as published by the Free Software Foundation; either version 2.1
11 * of the License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21 *
22 */
23
24 #include <linux/types.h>
25 #include <linux/errno.h>
26 #include <linux/string.h>
27 #include <linux/module.h>
28 #include <linux/kernel.h>
29 #include <linux/init.h>
30 #include <linux/slab.h>
31 #include <linux/device.h>
32 #include <linux/fs.h>
33 #include <linux/cdev.h>
34 #include <linux/mutex.h>
35 #include "dvbdev.h"
36
37 static DEFINE_MUTEX(dvbdev_mutex);
38 static int dvbdev_debug;
39
40 module_param(dvbdev_debug, int, 0644);
41 MODULE_PARM_DESC(dvbdev_debug, "Turn on/off device debugging (default:off).");
42
43 #define dprintk if (dvbdev_debug) printk
44
45 static LIST_HEAD(dvb_adapter_list);
46 static DEFINE_MUTEX(dvbdev_register_lock);
47
48 static const char * const dnames[] = {
49 "video", "audio", "sec", "frontend", "demux", "dvr", "ca",
50 "net", "osd"
51 };
52
53 #ifdef CONFIG_DVB_DYNAMIC_MINORS
54 #define MAX_DVB_MINORS 256
55 #define DVB_MAX_IDS MAX_DVB_MINORS
56 #else
57 #define DVB_MAX_IDS 4
58 #define nums2minor(num,type,id) ((num << 6) | (id << 4) | type)
59 #define MAX_DVB_MINORS (DVB_MAX_ADAPTERS*64)
60 #endif
61
62 static struct class *dvb_class;
63
64 static struct dvb_device *dvb_minors[MAX_DVB_MINORS];
65 static DECLARE_RWSEM(minor_rwsem);
66
dvb_device_open(struct inode * inode,struct file * file)67 static int dvb_device_open(struct inode *inode, struct file *file)
68 {
69 struct dvb_device *dvbdev;
70
71 mutex_lock(&dvbdev_mutex);
72 down_read(&minor_rwsem);
73 dvbdev = dvb_minors[iminor(inode)];
74
75 if (dvbdev && dvbdev->fops) {
76 int err = 0;
77 const struct file_operations *old_fops;
78
79 file->private_data = dvbdev;
80 old_fops = file->f_op;
81 file->f_op = fops_get(dvbdev->fops);
82 if (file->f_op == NULL) {
83 file->f_op = old_fops;
84 goto fail;
85 }
86 if(file->f_op->open)
87 err = file->f_op->open(inode,file);
88 if (err) {
89 fops_put(file->f_op);
90 file->f_op = fops_get(old_fops);
91 }
92 fops_put(old_fops);
93 up_read(&minor_rwsem);
94 mutex_unlock(&dvbdev_mutex);
95 return err;
96 }
97 fail:
98 up_read(&minor_rwsem);
99 mutex_unlock(&dvbdev_mutex);
100 return -ENODEV;
101 }
102
103
104 static const struct file_operations dvb_device_fops =
105 {
106 .owner = THIS_MODULE,
107 .open = dvb_device_open,
108 .llseek = noop_llseek,
109 };
110
111 static struct cdev dvb_device_cdev;
112
dvb_generic_open(struct inode * inode,struct file * file)113 int dvb_generic_open(struct inode *inode, struct file *file)
114 {
115 struct dvb_device *dvbdev = file->private_data;
116
117 if (!dvbdev)
118 return -ENODEV;
119
120 if (!dvbdev->users)
121 return -EBUSY;
122
123 if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
124 if (!dvbdev->readers)
125 return -EBUSY;
126 dvbdev->readers--;
127 } else {
128 if (!dvbdev->writers)
129 return -EBUSY;
130 dvbdev->writers--;
131 }
132
133 dvbdev->users--;
134 return 0;
135 }
136 EXPORT_SYMBOL(dvb_generic_open);
137
138
dvb_generic_release(struct inode * inode,struct file * file)139 int dvb_generic_release(struct inode *inode, struct file *file)
140 {
141 struct dvb_device *dvbdev = file->private_data;
142
143 if (!dvbdev)
144 return -ENODEV;
145
146 if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
147 dvbdev->readers++;
148 } else {
149 dvbdev->writers++;
150 }
151
152 dvbdev->users++;
153 return 0;
154 }
155 EXPORT_SYMBOL(dvb_generic_release);
156
157
dvb_generic_ioctl(struct file * file,unsigned int cmd,unsigned long arg)158 long dvb_generic_ioctl(struct file *file,
159 unsigned int cmd, unsigned long arg)
160 {
161 struct dvb_device *dvbdev = file->private_data;
162
163 if (!dvbdev)
164 return -ENODEV;
165
166 if (!dvbdev->kernel_ioctl)
167 return -EINVAL;
168
169 return dvb_usercopy(file, cmd, arg, dvbdev->kernel_ioctl);
170 }
171 EXPORT_SYMBOL(dvb_generic_ioctl);
172
173
dvbdev_get_free_id(struct dvb_adapter * adap,int type)174 static int dvbdev_get_free_id (struct dvb_adapter *adap, int type)
175 {
176 u32 id = 0;
177
178 while (id < DVB_MAX_IDS) {
179 struct dvb_device *dev;
180 list_for_each_entry(dev, &adap->device_list, list_head)
181 if (dev->type == type && dev->id == id)
182 goto skip;
183 return id;
184 skip:
185 id++;
186 }
187 return -ENFILE;
188 }
189
190
dvb_register_device(struct dvb_adapter * adap,struct dvb_device ** pdvbdev,const struct dvb_device * template,void * priv,int type)191 int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
192 const struct dvb_device *template, void *priv, int type)
193 {
194 struct dvb_device *dvbdev;
195 struct file_operations *dvbdevfops;
196 struct device *clsdev;
197 int minor;
198 int id;
199
200 mutex_lock(&dvbdev_register_lock);
201
202 if ((id = dvbdev_get_free_id (adap, type)) < 0){
203 mutex_unlock(&dvbdev_register_lock);
204 *pdvbdev = NULL;
205 printk(KERN_ERR "%s: couldn't find free device id\n", __func__);
206 return -ENFILE;
207 }
208
209 *pdvbdev = dvbdev = kmalloc(sizeof(struct dvb_device), GFP_KERNEL);
210
211 if (!dvbdev){
212 mutex_unlock(&dvbdev_register_lock);
213 return -ENOMEM;
214 }
215
216 dvbdevfops = kzalloc(sizeof(struct file_operations), GFP_KERNEL);
217
218 if (!dvbdevfops){
219 kfree (dvbdev);
220 mutex_unlock(&dvbdev_register_lock);
221 return -ENOMEM;
222 }
223
224 memcpy(dvbdev, template, sizeof(struct dvb_device));
225 dvbdev->type = type;
226 dvbdev->id = id;
227 dvbdev->adapter = adap;
228 dvbdev->priv = priv;
229 dvbdev->fops = dvbdevfops;
230 init_waitqueue_head (&dvbdev->wait_queue);
231
232 memcpy(dvbdevfops, template->fops, sizeof(struct file_operations));
233 dvbdevfops->owner = adap->module;
234
235 list_add_tail (&dvbdev->list_head, &adap->device_list);
236
237 down_write(&minor_rwsem);
238 #ifdef CONFIG_DVB_DYNAMIC_MINORS
239 for (minor = 0; minor < MAX_DVB_MINORS; minor++)
240 if (dvb_minors[minor] == NULL)
241 break;
242
243 if (minor == MAX_DVB_MINORS) {
244 kfree(dvbdevfops);
245 kfree(dvbdev);
246 up_write(&minor_rwsem);
247 mutex_unlock(&dvbdev_register_lock);
248 return -EINVAL;
249 }
250 #else
251 minor = nums2minor(adap->num, type, id);
252 #endif
253
254 dvbdev->minor = minor;
255 dvb_minors[minor] = dvbdev;
256 up_write(&minor_rwsem);
257
258 mutex_unlock(&dvbdev_register_lock);
259
260 clsdev = device_create(dvb_class, adap->device,
261 MKDEV(DVB_MAJOR, minor),
262 dvbdev, "dvb%d.%s%d", adap->num, dnames[type], id);
263 if (IS_ERR(clsdev)) {
264 printk(KERN_ERR "%s: failed to create device dvb%d.%s%d (%ld)\n",
265 __func__, adap->num, dnames[type], id, PTR_ERR(clsdev));
266 return PTR_ERR(clsdev);
267 }
268
269 dprintk(KERN_DEBUG "DVB: register adapter%d/%s%d @ minor: %i (0x%02x)\n",
270 adap->num, dnames[type], id, minor, minor);
271
272 return 0;
273 }
274 EXPORT_SYMBOL(dvb_register_device);
275
276
dvb_unregister_device(struct dvb_device * dvbdev)277 void dvb_unregister_device(struct dvb_device *dvbdev)
278 {
279 if (!dvbdev)
280 return;
281
282 down_write(&minor_rwsem);
283 dvb_minors[dvbdev->minor] = NULL;
284 up_write(&minor_rwsem);
285
286 device_destroy(dvb_class, MKDEV(DVB_MAJOR, dvbdev->minor));
287
288 list_del (&dvbdev->list_head);
289 kfree (dvbdev->fops);
290 kfree (dvbdev);
291 }
292 EXPORT_SYMBOL(dvb_unregister_device);
293
dvbdev_check_free_adapter_num(int num)294 static int dvbdev_check_free_adapter_num(int num)
295 {
296 struct list_head *entry;
297 list_for_each(entry, &dvb_adapter_list) {
298 struct dvb_adapter *adap;
299 adap = list_entry(entry, struct dvb_adapter, list_head);
300 if (adap->num == num)
301 return 0;
302 }
303 return 1;
304 }
305
dvbdev_get_free_adapter_num(void)306 static int dvbdev_get_free_adapter_num (void)
307 {
308 int num = 0;
309
310 while (num < DVB_MAX_ADAPTERS) {
311 if (dvbdev_check_free_adapter_num(num))
312 return num;
313 num++;
314 }
315
316 return -ENFILE;
317 }
318
319
dvb_register_adapter(struct dvb_adapter * adap,const char * name,struct module * module,struct device * device,short * adapter_nums)320 int dvb_register_adapter(struct dvb_adapter *adap, const char *name,
321 struct module *module, struct device *device,
322 short *adapter_nums)
323 {
324 int i, num;
325
326 mutex_lock(&dvbdev_register_lock);
327
328 for (i = 0; i < DVB_MAX_ADAPTERS; ++i) {
329 num = adapter_nums[i];
330 if (num >= 0 && num < DVB_MAX_ADAPTERS) {
331 /* use the one the driver asked for */
332 if (dvbdev_check_free_adapter_num(num))
333 break;
334 } else {
335 num = dvbdev_get_free_adapter_num();
336 break;
337 }
338 num = -1;
339 }
340
341 if (num < 0) {
342 mutex_unlock(&dvbdev_register_lock);
343 return -ENFILE;
344 }
345
346 memset (adap, 0, sizeof(struct dvb_adapter));
347 INIT_LIST_HEAD (&adap->device_list);
348
349 printk(KERN_INFO "DVB: registering new adapter (%s)\n", name);
350
351 adap->num = num;
352 adap->name = name;
353 adap->module = module;
354 adap->device = device;
355 adap->mfe_shared = 0;
356 adap->mfe_dvbdev = NULL;
357 mutex_init (&adap->mfe_lock);
358
359 list_add_tail (&adap->list_head, &dvb_adapter_list);
360
361 mutex_unlock(&dvbdev_register_lock);
362
363 return num;
364 }
365 EXPORT_SYMBOL(dvb_register_adapter);
366
367
dvb_unregister_adapter(struct dvb_adapter * adap)368 int dvb_unregister_adapter(struct dvb_adapter *adap)
369 {
370 mutex_lock(&dvbdev_register_lock);
371 list_del (&adap->list_head);
372 mutex_unlock(&dvbdev_register_lock);
373 return 0;
374 }
375 EXPORT_SYMBOL(dvb_unregister_adapter);
376
377 /* if the miracle happens and "generic_usercopy()" is included into
378 the kernel, then this can vanish. please don't make the mistake and
379 define this as video_usercopy(). this will introduce a dependecy
380 to the v4l "videodev.o" module, which is unnecessary for some
381 cards (ie. the budget dvb-cards don't need the v4l module...) */
dvb_usercopy(struct file * file,unsigned int cmd,unsigned long arg,int (* func)(struct file * file,unsigned int cmd,void * arg))382 int dvb_usercopy(struct file *file,
383 unsigned int cmd, unsigned long arg,
384 int (*func)(struct file *file,
385 unsigned int cmd, void *arg))
386 {
387 char sbuf[128];
388 void *mbuf = NULL;
389 void *parg = NULL;
390 int err = -EINVAL;
391
392 /* Copy arguments into temp kernel buffer */
393 switch (_IOC_DIR(cmd)) {
394 case _IOC_NONE:
395 /*
396 * For this command, the pointer is actually an integer
397 * argument.
398 */
399 parg = (void *) arg;
400 break;
401 case _IOC_READ: /* some v4l ioctls are marked wrong ... */
402 case _IOC_WRITE:
403 case (_IOC_WRITE | _IOC_READ):
404 if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
405 parg = sbuf;
406 } else {
407 /* too big to allocate from stack */
408 mbuf = kmalloc(_IOC_SIZE(cmd),GFP_KERNEL);
409 if (NULL == mbuf)
410 return -ENOMEM;
411 parg = mbuf;
412 }
413
414 err = -EFAULT;
415 if (copy_from_user(parg, (void __user *)arg, _IOC_SIZE(cmd)))
416 goto out;
417 break;
418 }
419
420 /* call driver */
421 mutex_lock(&dvbdev_mutex);
422 if ((err = func(file, cmd, parg)) == -ENOIOCTLCMD)
423 err = -EINVAL;
424 mutex_unlock(&dvbdev_mutex);
425
426 if (err < 0)
427 goto out;
428
429 /* Copy results into user buffer */
430 switch (_IOC_DIR(cmd))
431 {
432 case _IOC_READ:
433 case (_IOC_WRITE | _IOC_READ):
434 if (copy_to_user((void __user *)arg, parg, _IOC_SIZE(cmd)))
435 err = -EFAULT;
436 break;
437 }
438
439 out:
440 kfree(mbuf);
441 return err;
442 }
443
dvb_uevent(struct device * dev,struct kobj_uevent_env * env)444 static int dvb_uevent(struct device *dev, struct kobj_uevent_env *env)
445 {
446 struct dvb_device *dvbdev = dev_get_drvdata(dev);
447
448 add_uevent_var(env, "DVB_ADAPTER_NUM=%d", dvbdev->adapter->num);
449 add_uevent_var(env, "DVB_DEVICE_TYPE=%s", dnames[dvbdev->type]);
450 add_uevent_var(env, "DVB_DEVICE_NUM=%d", dvbdev->id);
451 return 0;
452 }
453
dvb_devnode(struct device * dev,umode_t * mode)454 static char *dvb_devnode(struct device *dev, umode_t *mode)
455 {
456 struct dvb_device *dvbdev = dev_get_drvdata(dev);
457
458 return kasprintf(GFP_KERNEL, "dvb/adapter%d/%s%d",
459 dvbdev->adapter->num, dnames[dvbdev->type], dvbdev->id);
460 }
461
462
init_dvbdev(void)463 static int __init init_dvbdev(void)
464 {
465 int retval;
466 dev_t dev = MKDEV(DVB_MAJOR, 0);
467
468 if ((retval = register_chrdev_region(dev, MAX_DVB_MINORS, "DVB")) != 0) {
469 printk(KERN_ERR "dvb-core: unable to get major %d\n", DVB_MAJOR);
470 return retval;
471 }
472
473 cdev_init(&dvb_device_cdev, &dvb_device_fops);
474 if ((retval = cdev_add(&dvb_device_cdev, dev, MAX_DVB_MINORS)) != 0) {
475 printk(KERN_ERR "dvb-core: unable register character device\n");
476 goto error;
477 }
478
479 dvb_class = class_create(THIS_MODULE, "dvb");
480 if (IS_ERR(dvb_class)) {
481 retval = PTR_ERR(dvb_class);
482 goto error;
483 }
484 dvb_class->dev_uevent = dvb_uevent;
485 dvb_class->devnode = dvb_devnode;
486 return 0;
487
488 error:
489 cdev_del(&dvb_device_cdev);
490 unregister_chrdev_region(dev, MAX_DVB_MINORS);
491 return retval;
492 }
493
494
exit_dvbdev(void)495 static void __exit exit_dvbdev(void)
496 {
497 class_destroy(dvb_class);
498 cdev_del(&dvb_device_cdev);
499 unregister_chrdev_region(MKDEV(DVB_MAJOR, 0), MAX_DVB_MINORS);
500 }
501
502 subsys_initcall(init_dvbdev);
503 module_exit(exit_dvbdev);
504
505 MODULE_DESCRIPTION("DVB Core Driver");
506 MODULE_AUTHOR("Marcus Metzler, Ralph Metzler, Holger Waechtler");
507 MODULE_LICENSE("GPL");
508