xref: /openbmc/linux/drivers/media/dvb-core/dvbdev.c (revision 4f3db074)
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 
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 *new_fops;
78 
79 		new_fops = fops_get(dvbdev->fops);
80 		if (!new_fops)
81 			goto fail;
82 		file->private_data = dvbdev;
83 		replace_fops(file, new_fops);
84 		if (file->f_op->open)
85 			err = file->f_op->open(inode,file);
86 		up_read(&minor_rwsem);
87 		mutex_unlock(&dvbdev_mutex);
88 		return err;
89 	}
90 fail:
91 	up_read(&minor_rwsem);
92 	mutex_unlock(&dvbdev_mutex);
93 	return -ENODEV;
94 }
95 
96 
97 static const struct file_operations dvb_device_fops =
98 {
99 	.owner =	THIS_MODULE,
100 	.open =		dvb_device_open,
101 	.llseek =	noop_llseek,
102 };
103 
104 static struct cdev dvb_device_cdev;
105 
106 int dvb_generic_open(struct inode *inode, struct file *file)
107 {
108 	struct dvb_device *dvbdev = file->private_data;
109 
110 	if (!dvbdev)
111 		return -ENODEV;
112 
113 	if (!dvbdev->users)
114 		return -EBUSY;
115 
116 	if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
117 		if (!dvbdev->readers)
118 			return -EBUSY;
119 		dvbdev->readers--;
120 	} else {
121 		if (!dvbdev->writers)
122 			return -EBUSY;
123 		dvbdev->writers--;
124 	}
125 
126 	dvbdev->users--;
127 	return 0;
128 }
129 EXPORT_SYMBOL(dvb_generic_open);
130 
131 
132 int dvb_generic_release(struct inode *inode, struct file *file)
133 {
134 	struct dvb_device *dvbdev = file->private_data;
135 
136 	if (!dvbdev)
137 		return -ENODEV;
138 
139 	if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
140 		dvbdev->readers++;
141 	} else {
142 		dvbdev->writers++;
143 	}
144 
145 	dvbdev->users++;
146 	return 0;
147 }
148 EXPORT_SYMBOL(dvb_generic_release);
149 
150 
151 long dvb_generic_ioctl(struct file *file,
152 		       unsigned int cmd, unsigned long arg)
153 {
154 	struct dvb_device *dvbdev = file->private_data;
155 
156 	if (!dvbdev)
157 		return -ENODEV;
158 
159 	if (!dvbdev->kernel_ioctl)
160 		return -EINVAL;
161 
162 	return dvb_usercopy(file, cmd, arg, dvbdev->kernel_ioctl);
163 }
164 EXPORT_SYMBOL(dvb_generic_ioctl);
165 
166 
167 static int dvbdev_get_free_id (struct dvb_adapter *adap, int type)
168 {
169 	u32 id = 0;
170 
171 	while (id < DVB_MAX_IDS) {
172 		struct dvb_device *dev;
173 		list_for_each_entry(dev, &adap->device_list, list_head)
174 			if (dev->type == type && dev->id == id)
175 				goto skip;
176 		return id;
177 skip:
178 		id++;
179 	}
180 	return -ENFILE;
181 }
182 
183 static void dvb_register_media_device(struct dvb_device *dvbdev,
184 				      int type, int minor)
185 {
186 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
187 	int ret = 0, npads;
188 
189 	if (!dvbdev->adapter->mdev)
190 		return;
191 
192 	dvbdev->entity = kzalloc(sizeof(*dvbdev->entity), GFP_KERNEL);
193 	if (!dvbdev->entity)
194 		return;
195 
196 	dvbdev->entity->info.dev.major = DVB_MAJOR;
197 	dvbdev->entity->info.dev.minor = minor;
198 	dvbdev->entity->name = dvbdev->name;
199 
200 	switch (type) {
201 	case DVB_DEVICE_CA:
202 	case DVB_DEVICE_DEMUX:
203 	case DVB_DEVICE_FRONTEND:
204 		npads = 2;
205 		break;
206 	case DVB_DEVICE_NET:
207 		npads = 0;
208 		break;
209 	default:
210 		npads = 1;
211 	}
212 
213 	if (npads) {
214 		dvbdev->pads = kcalloc(npads, sizeof(*dvbdev->pads),
215 				       GFP_KERNEL);
216 		if (!dvbdev->pads) {
217 			kfree(dvbdev->entity);
218 			return;
219 		}
220 	}
221 
222 	switch (type) {
223 	case DVB_DEVICE_FRONTEND:
224 		dvbdev->entity->type = MEDIA_ENT_T_DEVNODE_DVB_FE;
225 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
226 		dvbdev->pads[1].flags = MEDIA_PAD_FL_SOURCE;
227 		break;
228 	case DVB_DEVICE_DEMUX:
229 		dvbdev->entity->type = MEDIA_ENT_T_DEVNODE_DVB_DEMUX;
230 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
231 		dvbdev->pads[1].flags = MEDIA_PAD_FL_SOURCE;
232 		break;
233 	case DVB_DEVICE_DVR:
234 		dvbdev->entity->type = MEDIA_ENT_T_DEVNODE_DVB_DVR;
235 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
236 		break;
237 	case DVB_DEVICE_CA:
238 		dvbdev->entity->type = MEDIA_ENT_T_DEVNODE_DVB_CA;
239 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
240 		dvbdev->pads[1].flags = MEDIA_PAD_FL_SOURCE;
241 		break;
242 	case DVB_DEVICE_NET:
243 		dvbdev->entity->type = MEDIA_ENT_T_DEVNODE_DVB_NET;
244 		break;
245 	default:
246 		kfree(dvbdev->entity);
247 		dvbdev->entity = NULL;
248 		return;
249 	}
250 
251 	if (npads)
252 		ret = media_entity_init(dvbdev->entity, npads, dvbdev->pads, 0);
253 	if (!ret)
254 		ret = media_device_register_entity(dvbdev->adapter->mdev,
255 						   dvbdev->entity);
256 	if (ret < 0) {
257 		printk(KERN_ERR
258 			"%s: media_device_register_entity failed for %s\n",
259 			__func__, dvbdev->entity->name);
260 		kfree(dvbdev->pads);
261 		kfree(dvbdev->entity);
262 		dvbdev->entity = NULL;
263 		return;
264 	}
265 
266 	printk(KERN_DEBUG "%s: media device '%s' registered.\n",
267 		__func__, dvbdev->entity->name);
268 #endif
269 }
270 
271 int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
272 			const struct dvb_device *template, void *priv, int type)
273 {
274 	struct dvb_device *dvbdev;
275 	struct file_operations *dvbdevfops;
276 	struct device *clsdev;
277 	int minor;
278 	int id;
279 
280 	mutex_lock(&dvbdev_register_lock);
281 
282 	if ((id = dvbdev_get_free_id (adap, type)) < 0){
283 		mutex_unlock(&dvbdev_register_lock);
284 		*pdvbdev = NULL;
285 		printk(KERN_ERR "%s: couldn't find free device id\n", __func__);
286 		return -ENFILE;
287 	}
288 
289 	*pdvbdev = dvbdev = kmalloc(sizeof(struct dvb_device), GFP_KERNEL);
290 
291 	if (!dvbdev){
292 		mutex_unlock(&dvbdev_register_lock);
293 		return -ENOMEM;
294 	}
295 
296 	dvbdevfops = kzalloc(sizeof(struct file_operations), GFP_KERNEL);
297 
298 	if (!dvbdevfops){
299 		kfree (dvbdev);
300 		mutex_unlock(&dvbdev_register_lock);
301 		return -ENOMEM;
302 	}
303 
304 	memcpy(dvbdev, template, sizeof(struct dvb_device));
305 	dvbdev->type = type;
306 	dvbdev->id = id;
307 	dvbdev->adapter = adap;
308 	dvbdev->priv = priv;
309 	dvbdev->fops = dvbdevfops;
310 	init_waitqueue_head (&dvbdev->wait_queue);
311 
312 	memcpy(dvbdevfops, template->fops, sizeof(struct file_operations));
313 	dvbdevfops->owner = adap->module;
314 
315 	list_add_tail (&dvbdev->list_head, &adap->device_list);
316 
317 	down_write(&minor_rwsem);
318 #ifdef CONFIG_DVB_DYNAMIC_MINORS
319 	for (minor = 0; minor < MAX_DVB_MINORS; minor++)
320 		if (dvb_minors[minor] == NULL)
321 			break;
322 
323 	if (minor == MAX_DVB_MINORS) {
324 		kfree(dvbdevfops);
325 		kfree(dvbdev);
326 		up_write(&minor_rwsem);
327 		mutex_unlock(&dvbdev_register_lock);
328 		return -EINVAL;
329 	}
330 #else
331 	minor = nums2minor(adap->num, type, id);
332 #endif
333 
334 	dvbdev->minor = minor;
335 	dvb_minors[minor] = dvbdev;
336 	up_write(&minor_rwsem);
337 
338 	mutex_unlock(&dvbdev_register_lock);
339 
340 	clsdev = device_create(dvb_class, adap->device,
341 			       MKDEV(DVB_MAJOR, minor),
342 			       dvbdev, "dvb%d.%s%d", adap->num, dnames[type], id);
343 	if (IS_ERR(clsdev)) {
344 		printk(KERN_ERR "%s: failed to create device dvb%d.%s%d (%ld)\n",
345 		       __func__, adap->num, dnames[type], id, PTR_ERR(clsdev));
346 		return PTR_ERR(clsdev);
347 	}
348 	dprintk(KERN_DEBUG "DVB: register adapter%d/%s%d @ minor: %i (0x%02x)\n",
349 		adap->num, dnames[type], id, minor, minor);
350 
351 	dvb_register_media_device(dvbdev, type, minor);
352 
353 	return 0;
354 }
355 EXPORT_SYMBOL(dvb_register_device);
356 
357 
358 void dvb_unregister_device(struct dvb_device *dvbdev)
359 {
360 	if (!dvbdev)
361 		return;
362 
363 	down_write(&minor_rwsem);
364 	dvb_minors[dvbdev->minor] = NULL;
365 	up_write(&minor_rwsem);
366 
367 	device_destroy(dvb_class, MKDEV(DVB_MAJOR, dvbdev->minor));
368 
369 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
370 	if (dvbdev->entity) {
371 		media_device_unregister_entity(dvbdev->entity);
372 		kfree(dvbdev->entity);
373 		kfree(dvbdev->pads);
374 	}
375 #endif
376 
377 	list_del (&dvbdev->list_head);
378 	kfree (dvbdev->fops);
379 	kfree (dvbdev);
380 }
381 EXPORT_SYMBOL(dvb_unregister_device);
382 
383 
384 #ifdef CONFIG_MEDIA_CONTROLLER_DVB
385 void dvb_create_media_graph(struct dvb_adapter *adap)
386 {
387 	struct media_device *mdev = adap->mdev;
388 	struct media_entity *entity, *tuner = NULL, *fe = NULL;
389 	struct media_entity *demux = NULL, *dvr = NULL, *ca = NULL;
390 
391 	if (!mdev)
392 		return;
393 
394 	media_device_for_each_entity(entity, mdev) {
395 		switch (entity->type) {
396 		case MEDIA_ENT_T_V4L2_SUBDEV_TUNER:
397 			tuner = entity;
398 			break;
399 		case MEDIA_ENT_T_DEVNODE_DVB_FE:
400 			fe = entity;
401 			break;
402 		case MEDIA_ENT_T_DEVNODE_DVB_DEMUX:
403 			demux = entity;
404 			break;
405 		case MEDIA_ENT_T_DEVNODE_DVB_DVR:
406 			dvr = entity;
407 			break;
408 		case MEDIA_ENT_T_DEVNODE_DVB_CA:
409 			ca = entity;
410 			break;
411 		}
412 	}
413 
414 	if (tuner && fe)
415 		media_entity_create_link(tuner, 0, fe, 0, 0);
416 
417 	if (fe && demux)
418 		media_entity_create_link(fe, 1, demux, 0, MEDIA_LNK_FL_ENABLED);
419 
420 	if (demux && dvr)
421 		media_entity_create_link(demux, 1, dvr, 0, MEDIA_LNK_FL_ENABLED);
422 
423 	if (demux && ca)
424 		media_entity_create_link(demux, 1, ca, 0, MEDIA_LNK_FL_ENABLED);
425 }
426 EXPORT_SYMBOL_GPL(dvb_create_media_graph);
427 #endif
428 
429 static int dvbdev_check_free_adapter_num(int num)
430 {
431 	struct list_head *entry;
432 	list_for_each(entry, &dvb_adapter_list) {
433 		struct dvb_adapter *adap;
434 		adap = list_entry(entry, struct dvb_adapter, list_head);
435 		if (adap->num == num)
436 			return 0;
437 	}
438 	return 1;
439 }
440 
441 static int dvbdev_get_free_adapter_num (void)
442 {
443 	int num = 0;
444 
445 	while (num < DVB_MAX_ADAPTERS) {
446 		if (dvbdev_check_free_adapter_num(num))
447 			return num;
448 		num++;
449 	}
450 
451 	return -ENFILE;
452 }
453 
454 
455 int dvb_register_adapter(struct dvb_adapter *adap, const char *name,
456 			 struct module *module, struct device *device,
457 			 short *adapter_nums)
458 {
459 	int i, num;
460 
461 	mutex_lock(&dvbdev_register_lock);
462 
463 	for (i = 0; i < DVB_MAX_ADAPTERS; ++i) {
464 		num = adapter_nums[i];
465 		if (num >= 0  &&  num < DVB_MAX_ADAPTERS) {
466 		/* use the one the driver asked for */
467 			if (dvbdev_check_free_adapter_num(num))
468 				break;
469 		} else {
470 			num = dvbdev_get_free_adapter_num();
471 			break;
472 		}
473 		num = -1;
474 	}
475 
476 	if (num < 0) {
477 		mutex_unlock(&dvbdev_register_lock);
478 		return -ENFILE;
479 	}
480 
481 	memset (adap, 0, sizeof(struct dvb_adapter));
482 	INIT_LIST_HEAD (&adap->device_list);
483 
484 	printk(KERN_INFO "DVB: registering new adapter (%s)\n", name);
485 
486 	adap->num = num;
487 	adap->name = name;
488 	adap->module = module;
489 	adap->device = device;
490 	adap->mfe_shared = 0;
491 	adap->mfe_dvbdev = NULL;
492 	mutex_init (&adap->mfe_lock);
493 
494 	list_add_tail (&adap->list_head, &dvb_adapter_list);
495 
496 	mutex_unlock(&dvbdev_register_lock);
497 
498 	return num;
499 }
500 EXPORT_SYMBOL(dvb_register_adapter);
501 
502 
503 int dvb_unregister_adapter(struct dvb_adapter *adap)
504 {
505 	mutex_lock(&dvbdev_register_lock);
506 	list_del (&adap->list_head);
507 	mutex_unlock(&dvbdev_register_lock);
508 	return 0;
509 }
510 EXPORT_SYMBOL(dvb_unregister_adapter);
511 
512 /* if the miracle happens and "generic_usercopy()" is included into
513    the kernel, then this can vanish. please don't make the mistake and
514    define this as video_usercopy(). this will introduce a dependecy
515    to the v4l "videodev.o" module, which is unnecessary for some
516    cards (ie. the budget dvb-cards don't need the v4l module...) */
517 int dvb_usercopy(struct file *file,
518 		     unsigned int cmd, unsigned long arg,
519 		     int (*func)(struct file *file,
520 		     unsigned int cmd, void *arg))
521 {
522 	char    sbuf[128];
523 	void    *mbuf = NULL;
524 	void    *parg = NULL;
525 	int     err  = -EINVAL;
526 
527 	/*  Copy arguments into temp kernel buffer  */
528 	switch (_IOC_DIR(cmd)) {
529 	case _IOC_NONE:
530 		/*
531 		 * For this command, the pointer is actually an integer
532 		 * argument.
533 		 */
534 		parg = (void *) arg;
535 		break;
536 	case _IOC_READ: /* some v4l ioctls are marked wrong ... */
537 	case _IOC_WRITE:
538 	case (_IOC_WRITE | _IOC_READ):
539 		if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
540 			parg = sbuf;
541 		} else {
542 			/* too big to allocate from stack */
543 			mbuf = kmalloc(_IOC_SIZE(cmd),GFP_KERNEL);
544 			if (NULL == mbuf)
545 				return -ENOMEM;
546 			parg = mbuf;
547 		}
548 
549 		err = -EFAULT;
550 		if (copy_from_user(parg, (void __user *)arg, _IOC_SIZE(cmd)))
551 			goto out;
552 		break;
553 	}
554 
555 	/* call driver */
556 	if ((err = func(file, cmd, parg)) == -ENOIOCTLCMD)
557 		err = -ENOTTY;
558 
559 	if (err < 0)
560 		goto out;
561 
562 	/*  Copy results into user buffer  */
563 	switch (_IOC_DIR(cmd))
564 	{
565 	case _IOC_READ:
566 	case (_IOC_WRITE | _IOC_READ):
567 		if (copy_to_user((void __user *)arg, parg, _IOC_SIZE(cmd)))
568 			err = -EFAULT;
569 		break;
570 	}
571 
572 out:
573 	kfree(mbuf);
574 	return err;
575 }
576 
577 static int dvb_uevent(struct device *dev, struct kobj_uevent_env *env)
578 {
579 	struct dvb_device *dvbdev = dev_get_drvdata(dev);
580 
581 	add_uevent_var(env, "DVB_ADAPTER_NUM=%d", dvbdev->adapter->num);
582 	add_uevent_var(env, "DVB_DEVICE_TYPE=%s", dnames[dvbdev->type]);
583 	add_uevent_var(env, "DVB_DEVICE_NUM=%d", dvbdev->id);
584 	return 0;
585 }
586 
587 static char *dvb_devnode(struct device *dev, umode_t *mode)
588 {
589 	struct dvb_device *dvbdev = dev_get_drvdata(dev);
590 
591 	return kasprintf(GFP_KERNEL, "dvb/adapter%d/%s%d",
592 		dvbdev->adapter->num, dnames[dvbdev->type], dvbdev->id);
593 }
594 
595 
596 static int __init init_dvbdev(void)
597 {
598 	int retval;
599 	dev_t dev = MKDEV(DVB_MAJOR, 0);
600 
601 	if ((retval = register_chrdev_region(dev, MAX_DVB_MINORS, "DVB")) != 0) {
602 		printk(KERN_ERR "dvb-core: unable to get major %d\n", DVB_MAJOR);
603 		return retval;
604 	}
605 
606 	cdev_init(&dvb_device_cdev, &dvb_device_fops);
607 	if ((retval = cdev_add(&dvb_device_cdev, dev, MAX_DVB_MINORS)) != 0) {
608 		printk(KERN_ERR "dvb-core: unable register character device\n");
609 		goto error;
610 	}
611 
612 	dvb_class = class_create(THIS_MODULE, "dvb");
613 	if (IS_ERR(dvb_class)) {
614 		retval = PTR_ERR(dvb_class);
615 		goto error;
616 	}
617 	dvb_class->dev_uevent = dvb_uevent;
618 	dvb_class->devnode = dvb_devnode;
619 	return 0;
620 
621 error:
622 	cdev_del(&dvb_device_cdev);
623 	unregister_chrdev_region(dev, MAX_DVB_MINORS);
624 	return retval;
625 }
626 
627 
628 static void __exit exit_dvbdev(void)
629 {
630 	class_destroy(dvb_class);
631 	cdev_del(&dvb_device_cdev);
632 	unregister_chrdev_region(MKDEV(DVB_MAJOR, 0), MAX_DVB_MINORS);
633 }
634 
635 subsys_initcall(init_dvbdev);
636 module_exit(exit_dvbdev);
637 
638 MODULE_DESCRIPTION("DVB Core Driver");
639 MODULE_AUTHOR("Marcus Metzler, Ralph Metzler, Holger Waechtler");
640 MODULE_LICENSE("GPL");
641