Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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 <linux/smp_lock.h>
36#include "dvbdev.h"
37
38static int dvbdev_debug;
39
40module_param(dvbdev_debug, int, 0644);
41MODULE_PARM_DESC(dvbdev_debug, "Turn on/off device debugging (default:off).");
42
43#define dprintk if (dvbdev_debug) printk
44
45static LIST_HEAD(dvb_adapter_list);
46static DEFINE_MUTEX(dvbdev_register_lock);
47
48static 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
62static struct class *dvb_class;
63
64static struct dvb_device *dvb_minors[MAX_DVB_MINORS];
65static DECLARE_RWSEM(minor_rwsem);
66
67static int dvb_device_open(struct inode *inode, struct file *file)
68{
69 struct dvb_device *dvbdev;
70
71 lock_kernel();
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 unlock_kernel();
95 return err;
96 }
97fail:
98 up_read(&minor_rwsem);
99 unlock_kernel();
100 return -ENODEV;
101}
102
103
104static const struct file_operations dvb_device_fops =
105{
106 .owner = THIS_MODULE,
107 .open = dvb_device_open,
108};
109
110static struct cdev dvb_device_cdev;
111
112int dvb_generic_open(struct inode *inode, struct file *file)
113{
114 struct dvb_device *dvbdev = file->private_data;
115
116 if (!dvbdev)
117 return -ENODEV;
118
119 if (!dvbdev->users)
120 return -EBUSY;
121
122 if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
123 if (!dvbdev->readers)
124 return -EBUSY;
125 dvbdev->readers--;
126 } else {
127 if (!dvbdev->writers)
128 return -EBUSY;
129 dvbdev->writers--;
130 }
131
132 dvbdev->users--;
133 return 0;
134}
135EXPORT_SYMBOL(dvb_generic_open);
136
137
138int dvb_generic_release(struct inode *inode, struct file *file)
139{
140 struct dvb_device *dvbdev = file->private_data;
141
142 if (!dvbdev)
143 return -ENODEV;
144
145 if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
146 dvbdev->readers++;
147 } else {
148 dvbdev->writers++;
149 }
150
151 dvbdev->users++;
152 return 0;
153}
154EXPORT_SYMBOL(dvb_generic_release);
155
156
157long dvb_generic_ioctl(struct file *file,
158 unsigned int cmd, unsigned long arg)
159{
160 struct dvb_device *dvbdev = file->private_data;
161 int ret;
162
163 if (!dvbdev)
164 return -ENODEV;
165
166 if (!dvbdev->kernel_ioctl)
167 return -EINVAL;
168
169 lock_kernel();
170 ret = dvb_usercopy(file, cmd, arg, dvbdev->kernel_ioctl);
171 unlock_kernel();
172
173 return ret;
174}
175EXPORT_SYMBOL(dvb_generic_ioctl);
176
177
178static int dvbdev_get_free_id (struct dvb_adapter *adap, int type)
179{
180 u32 id = 0;
181
182 while (id < DVB_MAX_IDS) {
183 struct dvb_device *dev;
184 list_for_each_entry(dev, &adap->device_list, list_head)
185 if (dev->type == type && dev->id == id)
186 goto skip;
187 return id;
188skip:
189 id++;
190 }
191 return -ENFILE;
192}
193
194
195int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
196 const struct dvb_device *template, void *priv, int type)
197{
198 struct dvb_device *dvbdev;
199 struct file_operations *dvbdevfops;
200 struct device *clsdev;
201 int minor;
202 int id;
203
204 mutex_lock(&dvbdev_register_lock);
205
206 if ((id = dvbdev_get_free_id (adap, type)) < 0){
207 mutex_unlock(&dvbdev_register_lock);
208 *pdvbdev = NULL;
209 printk(KERN_ERR "%s: couldn't find free device id\n", __func__);
210 return -ENFILE;
211 }
212
213 *pdvbdev = dvbdev = kmalloc(sizeof(struct dvb_device), GFP_KERNEL);
214
215 if (!dvbdev){
216 mutex_unlock(&dvbdev_register_lock);
217 return -ENOMEM;
218 }
219
220 dvbdevfops = kzalloc(sizeof(struct file_operations), GFP_KERNEL);
221
222 if (!dvbdevfops){
223 kfree (dvbdev);
224 mutex_unlock(&dvbdev_register_lock);
225 return -ENOMEM;
226 }
227
228 memcpy(dvbdev, template, sizeof(struct dvb_device));
229 dvbdev->type = type;
230 dvbdev->id = id;
231 dvbdev->adapter = adap;
232 dvbdev->priv = priv;
233 dvbdev->fops = dvbdevfops;
234 init_waitqueue_head (&dvbdev->wait_queue);
235
236 memcpy(dvbdevfops, template->fops, sizeof(struct file_operations));
237 dvbdevfops->owner = adap->module;
238
239 list_add_tail (&dvbdev->list_head, &adap->device_list);
240
241 down_write(&minor_rwsem);
242#ifdef CONFIG_DVB_DYNAMIC_MINORS
243 for (minor = 0; minor < MAX_DVB_MINORS; minor++)
244 if (dvb_minors[minor] == NULL)
245 break;
246
247 if (minor == MAX_DVB_MINORS) {
248 kfree(dvbdevfops);
249 kfree(dvbdev);
250 mutex_unlock(&dvbdev_register_lock);
251 return -EINVAL;
252 }
253#else
254 minor = nums2minor(adap->num, type, id);
255#endif
256
257 dvbdev->minor = minor;
258 dvb_minors[minor] = dvbdev;
259 up_write(&minor_rwsem);
260
261 mutex_unlock(&dvbdev_register_lock);
262
263 clsdev = device_create(dvb_class, adap->device,
264 MKDEV(DVB_MAJOR, minor),
265 dvbdev, "dvb%d.%s%d", adap->num, dnames[type], id);
266 if (IS_ERR(clsdev)) {
267 printk(KERN_ERR "%s: failed to create device dvb%d.%s%d (%ld)\n",
268 __func__, adap->num, dnames[type], id, PTR_ERR(clsdev));
269 return PTR_ERR(clsdev);
270 }
271
272 dprintk(KERN_DEBUG "DVB: register adapter%d/%s%d @ minor: %i (0x%02x)\n",
273 adap->num, dnames[type], id, minor, minor);
274
275 return 0;
276}
277EXPORT_SYMBOL(dvb_register_device);
278
279
280void dvb_unregister_device(struct dvb_device *dvbdev)
281{
282 if (!dvbdev)
283 return;
284
285 down_write(&minor_rwsem);
286 dvb_minors[dvbdev->minor] = NULL;
287 up_write(&minor_rwsem);
288
289 device_destroy(dvb_class, MKDEV(DVB_MAJOR, dvbdev->minor));
290
291 list_del (&dvbdev->list_head);
292 kfree (dvbdev->fops);
293 kfree (dvbdev);
294}
295EXPORT_SYMBOL(dvb_unregister_device);
296
297static int dvbdev_check_free_adapter_num(int num)
298{
299 struct list_head *entry;
300 list_for_each(entry, &dvb_adapter_list) {
301 struct dvb_adapter *adap;
302 adap = list_entry(entry, struct dvb_adapter, list_head);
303 if (adap->num == num)
304 return 0;
305 }
306 return 1;
307}
308
309static int dvbdev_get_free_adapter_num (void)
310{
311 int num = 0;
312
313 while (num < DVB_MAX_ADAPTERS) {
314 if (dvbdev_check_free_adapter_num(num))
315 return num;
316 num++;
317 }
318
319 return -ENFILE;
320}
321
322
323int dvb_register_adapter(struct dvb_adapter *adap, const char *name,
324 struct module *module, struct device *device,
325 short *adapter_nums)
326{
327 int i, num;
328
329 mutex_lock(&dvbdev_register_lock);
330
331 for (i = 0; i < DVB_MAX_ADAPTERS; ++i) {
332 num = adapter_nums[i];
333 if (num >= 0 && num < DVB_MAX_ADAPTERS) {
334 /* use the one the driver asked for */
335 if (dvbdev_check_free_adapter_num(num))
336 break;
337 } else {
338 num = dvbdev_get_free_adapter_num();
339 break;
340 }
341 num = -1;
342 }
343
344 if (num < 0) {
345 mutex_unlock(&dvbdev_register_lock);
346 return -ENFILE;
347 }
348
349 memset (adap, 0, sizeof(struct dvb_adapter));
350 INIT_LIST_HEAD (&adap->device_list);
351
352 printk(KERN_INFO "DVB: registering new adapter (%s)\n", name);
353
354 adap->num = num;
355 adap->name = name;
356 adap->module = module;
357 adap->device = device;
358 adap->mfe_shared = 0;
359 adap->mfe_dvbdev = NULL;
360 mutex_init (&adap->mfe_lock);
361
362 list_add_tail (&adap->list_head, &dvb_adapter_list);
363
364 mutex_unlock(&dvbdev_register_lock);
365
366 return num;
367}
368EXPORT_SYMBOL(dvb_register_adapter);
369
370
371int dvb_unregister_adapter(struct dvb_adapter *adap)
372{
373 mutex_lock(&dvbdev_register_lock);
374 list_del (&adap->list_head);
375 mutex_unlock(&dvbdev_register_lock);
376 return 0;
377}
378EXPORT_SYMBOL(dvb_unregister_adapter);
379
380/* if the miracle happens and "generic_usercopy()" is included into
381 the kernel, then this can vanish. please don't make the mistake and
382 define this as video_usercopy(). this will introduce a dependecy
383 to the v4l "videodev.o" module, which is unnecessary for some
384 cards (ie. the budget dvb-cards don't need the v4l module...) */
385int dvb_usercopy(struct file *file,
386 unsigned int cmd, unsigned long arg,
387 int (*func)(struct file *file,
388 unsigned int cmd, void *arg))
389{
390 char sbuf[128];
391 void *mbuf = NULL;
392 void *parg = NULL;
393 int err = -EINVAL;
394
395 /* Copy arguments into temp kernel buffer */
396 switch (_IOC_DIR(cmd)) {
397 case _IOC_NONE:
398 /*
399 * For this command, the pointer is actually an integer
400 * argument.
401 */
402 parg = (void *) arg;
403 break;
404 case _IOC_READ: /* some v4l ioctls are marked wrong ... */
405 case _IOC_WRITE:
406 case (_IOC_WRITE | _IOC_READ):
407 if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
408 parg = sbuf;
409 } else {
410 /* too big to allocate from stack */
411 mbuf = kmalloc(_IOC_SIZE(cmd),GFP_KERNEL);
412 if (NULL == mbuf)
413 return -ENOMEM;
414 parg = mbuf;
415 }
416
417 err = -EFAULT;
418 if (copy_from_user(parg, (void __user *)arg, _IOC_SIZE(cmd)))
419 goto out;
420 break;
421 }
422
423 /* call driver */
424 if ((err = func(file, cmd, parg)) == -ENOIOCTLCMD)
425 err = -EINVAL;
426
427 if (err < 0)
428 goto out;
429
430 /* Copy results into user buffer */
431 switch (_IOC_DIR(cmd))
432 {
433 case _IOC_READ:
434 case (_IOC_WRITE | _IOC_READ):
435 if (copy_to_user((void __user *)arg, parg, _IOC_SIZE(cmd)))
436 err = -EFAULT;
437 break;
438 }
439
440out:
441 kfree(mbuf);
442 return err;
443}
444
445static int dvb_uevent(struct device *dev, struct kobj_uevent_env *env)
446{
447 struct dvb_device *dvbdev = dev_get_drvdata(dev);
448
449 add_uevent_var(env, "DVB_ADAPTER_NUM=%d", dvbdev->adapter->num);
450 add_uevent_var(env, "DVB_DEVICE_TYPE=%s", dnames[dvbdev->type]);
451 add_uevent_var(env, "DVB_DEVICE_NUM=%d", dvbdev->id);
452 return 0;
453}
454
455static char *dvb_devnode(struct device *dev, mode_t *mode)
456{
457 struct dvb_device *dvbdev = dev_get_drvdata(dev);
458
459 return kasprintf(GFP_KERNEL, "dvb/adapter%d/%s%d",
460 dvbdev->adapter->num, dnames[dvbdev->type], dvbdev->id);
461}
462
463
464static int __init init_dvbdev(void)
465{
466 int retval;
467 dev_t dev = MKDEV(DVB_MAJOR, 0);
468
469 if ((retval = register_chrdev_region(dev, MAX_DVB_MINORS, "DVB")) != 0) {
470 printk(KERN_ERR "dvb-core: unable to get major %d\n", DVB_MAJOR);
471 return retval;
472 }
473
474 cdev_init(&dvb_device_cdev, &dvb_device_fops);
475 if ((retval = cdev_add(&dvb_device_cdev, dev, MAX_DVB_MINORS)) != 0) {
476 printk(KERN_ERR "dvb-core: unable register character device\n");
477 goto error;
478 }
479
480 dvb_class = class_create(THIS_MODULE, "dvb");
481 if (IS_ERR(dvb_class)) {
482 retval = PTR_ERR(dvb_class);
483 goto error;
484 }
485 dvb_class->dev_uevent = dvb_uevent;
486 dvb_class->devnode = dvb_devnode;
487 return 0;
488
489error:
490 cdev_del(&dvb_device_cdev);
491 unregister_chrdev_region(dev, MAX_DVB_MINORS);
492 return retval;
493}
494
495
496static void __exit exit_dvbdev(void)
497{
498 class_destroy(dvb_class);
499 cdev_del(&dvb_device_cdev);
500 unregister_chrdev_region(MKDEV(DVB_MAJOR, 0), MAX_DVB_MINORS);
501}
502
503subsys_initcall(init_dvbdev);
504module_exit(exit_dvbdev);
505
506MODULE_DESCRIPTION("DVB Core Driver");
507MODULE_AUTHOR("Marcus Metzler, Ralph Metzler, Holger Waechtler");
508MODULE_LICENSE("GPL");