xref: /linux/drivers/media/dvb-core/dvbdev.c (revision 32786fdc9506aeba98278c1844d4bfb766863832)
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 #define pr_fmt(fmt) "dvbdev: " fmt
25 
26 #include <linux/types.h>
27 #include <linux/errno.h>
28 #include <linux/string.h>
29 #include <linux/module.h>
30 #include <linux/kernel.h>
31 #include <linux/init.h>
32 #include <linux/slab.h>
33 #include <linux/device.h>
34 #include <linux/fs.h>
35 #include <linux/cdev.h>
36 #include <linux/mutex.h>
37 #include "dvbdev.h"
38 
39 /* Due to enum tuner_pad_index */
40 #include <media/tuner.h>
41 
42 static DEFINE_MUTEX(dvbdev_mutex);
43 static int dvbdev_debug;
44 
45 module_param(dvbdev_debug, int, 0644);
46 MODULE_PARM_DESC(dvbdev_debug, "Turn on/off device debugging (default:off).");
47 
48 #define dprintk(fmt, arg...) do {					\
49 	if (dvbdev_debug)						\
50 		printk(KERN_DEBUG pr_fmt("%s: " fmt),			\
51 		       __func__, ##arg);				\
52 } while (0)
53 
54 static LIST_HEAD(dvb_adapter_list);
55 static DEFINE_MUTEX(dvbdev_register_lock);
56 
57 static const char * const dnames[] = {
58 	"video", "audio", "sec", "frontend", "demux", "dvr", "ca",
59 	"net", "osd"
60 };
61 
62 #ifdef CONFIG_DVB_DYNAMIC_MINORS
63 #define MAX_DVB_MINORS		256
64 #define DVB_MAX_IDS		MAX_DVB_MINORS
65 #else
66 #define DVB_MAX_IDS		4
67 #define nums2minor(num, type, id)	((num << 6) | (id << 4) | type)
68 #define MAX_DVB_MINORS		(DVB_MAX_ADAPTERS*64)
69 #endif
70 
71 static struct class *dvb_class;
72 
73 static struct dvb_device *dvb_minors[MAX_DVB_MINORS];
74 static DECLARE_RWSEM(minor_rwsem);
75 
76 static int dvb_device_open(struct inode *inode, struct file *file)
77 {
78 	struct dvb_device *dvbdev;
79 
80 	mutex_lock(&dvbdev_mutex);
81 	down_read(&minor_rwsem);
82 	dvbdev = dvb_minors[iminor(inode)];
83 
84 	if (dvbdev && dvbdev->fops) {
85 		int err = 0;
86 		const struct file_operations *new_fops;
87 
88 		new_fops = fops_get(dvbdev->fops);
89 		if (!new_fops)
90 			goto fail;
91 		file->private_data = dvbdev;
92 		replace_fops(file, new_fops);
93 		if (file->f_op->open)
94 			err = file->f_op->open(inode, file);
95 		up_read(&minor_rwsem);
96 		mutex_unlock(&dvbdev_mutex);
97 		return err;
98 	}
99 fail:
100 	up_read(&minor_rwsem);
101 	mutex_unlock(&dvbdev_mutex);
102 	return -ENODEV;
103 }
104 
105 
106 static const struct file_operations dvb_device_fops =
107 {
108 	.owner =	THIS_MODULE,
109 	.open =		dvb_device_open,
110 	.llseek =	noop_llseek,
111 };
112 
113 static struct cdev dvb_device_cdev;
114 
115 int dvb_generic_open(struct inode *inode, struct file *file)
116 {
117 	struct dvb_device *dvbdev = file->private_data;
118 
119 	if (!dvbdev)
120 		return -ENODEV;
121 
122 	if (!dvbdev->users)
123 		return -EBUSY;
124 
125 	if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
126 		if (!dvbdev->readers)
127 			return -EBUSY;
128 		dvbdev->readers--;
129 	} else {
130 		if (!dvbdev->writers)
131 			return -EBUSY;
132 		dvbdev->writers--;
133 	}
134 
135 	dvbdev->users--;
136 	return 0;
137 }
138 EXPORT_SYMBOL(dvb_generic_open);
139 
140 
141 int dvb_generic_release(struct inode *inode, struct file *file)
142 {
143 	struct dvb_device *dvbdev = file->private_data;
144 
145 	if (!dvbdev)
146 		return -ENODEV;
147 
148 	if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
149 		dvbdev->readers++;
150 	} else {
151 		dvbdev->writers++;
152 	}
153 
154 	dvbdev->users++;
155 	return 0;
156 }
157 EXPORT_SYMBOL(dvb_generic_release);
158 
159 
160 long dvb_generic_ioctl(struct file *file,
161 		       unsigned int cmd, unsigned long arg)
162 {
163 	struct dvb_device *dvbdev = file->private_data;
164 
165 	if (!dvbdev)
166 		return -ENODEV;
167 
168 	if (!dvbdev->kernel_ioctl)
169 		return -EINVAL;
170 
171 	return dvb_usercopy(file, cmd, arg, dvbdev->kernel_ioctl);
172 }
173 EXPORT_SYMBOL(dvb_generic_ioctl);
174 
175 
176 static int dvbdev_get_free_id (struct dvb_adapter *adap, int type)
177 {
178 	u32 id = 0;
179 
180 	while (id < DVB_MAX_IDS) {
181 		struct dvb_device *dev;
182 		list_for_each_entry(dev, &adap->device_list, list_head)
183 			if (dev->type == type && dev->id == id)
184 				goto skip;
185 		return id;
186 skip:
187 		id++;
188 	}
189 	return -ENFILE;
190 }
191 
192 static void dvb_media_device_free(struct dvb_device *dvbdev)
193 {
194 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
195 	if (dvbdev->entity) {
196 		media_device_unregister_entity(dvbdev->entity);
197 		kfree(dvbdev->entity);
198 		kfree(dvbdev->pads);
199 		dvbdev->entity = NULL;
200 		dvbdev->pads = NULL;
201 	}
202 
203 	if (dvbdev->tsout_entity) {
204 		int i;
205 
206 		for (i = 0; i < dvbdev->tsout_num_entities; i++) {
207 			media_device_unregister_entity(&dvbdev->tsout_entity[i]);
208 			kfree(dvbdev->tsout_entity[i].name);
209 		}
210 		kfree(dvbdev->tsout_entity);
211 		kfree(dvbdev->tsout_pads);
212 		dvbdev->tsout_entity = NULL;
213 		dvbdev->tsout_pads = NULL;
214 
215 		dvbdev->tsout_num_entities = 0;
216 	}
217 
218 	if (dvbdev->intf_devnode) {
219 		media_devnode_remove(dvbdev->intf_devnode);
220 		dvbdev->intf_devnode = NULL;
221 	}
222 
223 	if (dvbdev->adapter->conn) {
224 		media_device_unregister_entity(dvbdev->adapter->conn);
225 		dvbdev->adapter->conn = NULL;
226 		kfree(dvbdev->adapter->conn_pads);
227 		dvbdev->adapter->conn_pads = NULL;
228 	}
229 #endif
230 }
231 
232 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
233 static int dvb_create_tsout_entity(struct dvb_device *dvbdev,
234 				    const char *name, int npads)
235 {
236 	int i, ret = 0;
237 
238 	dvbdev->tsout_pads = kcalloc(npads, sizeof(*dvbdev->tsout_pads),
239 				     GFP_KERNEL);
240 	if (!dvbdev->tsout_pads)
241 		return -ENOMEM;
242 
243 	dvbdev->tsout_entity = kcalloc(npads, sizeof(*dvbdev->tsout_entity),
244 				       GFP_KERNEL);
245 	if (!dvbdev->tsout_entity)
246 		return -ENOMEM;
247 
248 	dvbdev->tsout_num_entities = npads;
249 
250 	for (i = 0; i < npads; i++) {
251 		struct media_pad *pads = &dvbdev->tsout_pads[i];
252 		struct media_entity *entity = &dvbdev->tsout_entity[i];
253 
254 		entity->name = kasprintf(GFP_KERNEL, "%s #%d", name, i);
255 		if (!entity->name)
256 			return -ENOMEM;
257 
258 		entity->function = MEDIA_ENT_F_IO_DTV;
259 		pads->flags = MEDIA_PAD_FL_SINK;
260 
261 		ret = media_entity_pads_init(entity, 1, pads);
262 		if (ret < 0)
263 			return ret;
264 
265 		ret = media_device_register_entity(dvbdev->adapter->mdev,
266 						   entity);
267 		if (ret < 0)
268 			return ret;
269 	}
270 	return 0;
271 }
272 
273 #define DEMUX_TSOUT	"demux-tsout"
274 #define DVR_TSOUT	"dvr-tsout"
275 
276 static int dvb_create_media_entity(struct dvb_device *dvbdev,
277 				   int type, int demux_sink_pads)
278 {
279 	int i, ret, npads;
280 
281 	switch (type) {
282 	case DVB_DEVICE_FRONTEND:
283 		npads = 2;
284 		break;
285 	case DVB_DEVICE_DVR:
286 		ret = dvb_create_tsout_entity(dvbdev, DVR_TSOUT,
287 					      demux_sink_pads);
288 		return ret;
289 	case DVB_DEVICE_DEMUX:
290 		npads = 1 + demux_sink_pads;
291 		ret = dvb_create_tsout_entity(dvbdev, DEMUX_TSOUT,
292 					      demux_sink_pads);
293 		if (ret < 0)
294 			return ret;
295 		break;
296 	case DVB_DEVICE_CA:
297 		npads = 2;
298 		break;
299 	case DVB_DEVICE_NET:
300 		/*
301 		 * We should be creating entities for the MPE/ULE
302 		 * decapsulation hardware (or software implementation).
303 		 *
304 		 * However, the number of for the MPE/ULE decaps may not be
305 		 * fixed. As we don't have yet dynamic support for PADs at
306 		 * the Media Controller, let's not create the decap
307 		 * entities yet.
308 		 */
309 		return 0;
310 	default:
311 		return 0;
312 	}
313 
314 	dvbdev->entity = kzalloc(sizeof(*dvbdev->entity), GFP_KERNEL);
315 	if (!dvbdev->entity)
316 		return -ENOMEM;
317 
318 	dvbdev->entity->name = dvbdev->name;
319 
320 	if (npads) {
321 		dvbdev->pads = kcalloc(npads, sizeof(*dvbdev->pads),
322 				       GFP_KERNEL);
323 		if (!dvbdev->pads)
324 			return -ENOMEM;
325 	}
326 
327 	switch (type) {
328 	case DVB_DEVICE_FRONTEND:
329 		dvbdev->entity->function = MEDIA_ENT_F_DTV_DEMOD;
330 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
331 		dvbdev->pads[1].flags = MEDIA_PAD_FL_SOURCE;
332 		break;
333 	case DVB_DEVICE_DEMUX:
334 		dvbdev->entity->function = MEDIA_ENT_F_TS_DEMUX;
335 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
336 		for (i = 1; i < npads; i++)
337 			dvbdev->pads[i].flags = MEDIA_PAD_FL_SOURCE;
338 		break;
339 	case DVB_DEVICE_CA:
340 		dvbdev->entity->function = MEDIA_ENT_F_DTV_CA;
341 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
342 		dvbdev->pads[1].flags = MEDIA_PAD_FL_SOURCE;
343 		break;
344 	default:
345 		/* Should never happen, as the first switch prevents it */
346 		kfree(dvbdev->entity);
347 		kfree(dvbdev->pads);
348 		dvbdev->entity = NULL;
349 		dvbdev->pads = NULL;
350 		return 0;
351 	}
352 
353 	if (npads) {
354 		ret = media_entity_pads_init(dvbdev->entity, npads, dvbdev->pads);
355 		if (ret)
356 			return ret;
357 	}
358 	ret = media_device_register_entity(dvbdev->adapter->mdev,
359 					   dvbdev->entity);
360 	if (ret)
361 		return ret;
362 
363 	pr_info("%s: media entity '%s' registered.\n",
364 		__func__, dvbdev->entity->name);
365 
366 	return 0;
367 }
368 #endif
369 
370 static int dvb_register_media_device(struct dvb_device *dvbdev,
371 				     int type, int minor,
372 				     unsigned demux_sink_pads)
373 {
374 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
375 	struct media_link *link;
376 	u32 intf_type;
377 	int ret;
378 
379 	if (!dvbdev->adapter->mdev)
380 		return 0;
381 
382 	ret = dvb_create_media_entity(dvbdev, type, demux_sink_pads);
383 	if (ret)
384 		return ret;
385 
386 	switch (type) {
387 	case DVB_DEVICE_FRONTEND:
388 		intf_type = MEDIA_INTF_T_DVB_FE;
389 		break;
390 	case DVB_DEVICE_DEMUX:
391 		intf_type = MEDIA_INTF_T_DVB_DEMUX;
392 		break;
393 	case DVB_DEVICE_DVR:
394 		intf_type = MEDIA_INTF_T_DVB_DVR;
395 		break;
396 	case DVB_DEVICE_CA:
397 		intf_type = MEDIA_INTF_T_DVB_CA;
398 		break;
399 	case DVB_DEVICE_NET:
400 		intf_type = MEDIA_INTF_T_DVB_NET;
401 		break;
402 	default:
403 		return 0;
404 	}
405 
406 	dvbdev->intf_devnode = media_devnode_create(dvbdev->adapter->mdev,
407 						    intf_type, 0,
408 						    DVB_MAJOR, minor);
409 
410 	if (!dvbdev->intf_devnode)
411 		return -ENOMEM;
412 
413 	/*
414 	 * Create the "obvious" link, e. g. the ones that represent
415 	 * a direct association between an interface and an entity.
416 	 * Other links should be created elsewhere, like:
417 	 *		DVB FE intf    -> tuner
418 	 *		DVB demux intf -> dvr
419 	 */
420 
421 	if (!dvbdev->entity)
422 		return 0;
423 
424 	link = media_create_intf_link(dvbdev->entity, &dvbdev->intf_devnode->intf,
425 				      MEDIA_LNK_FL_ENABLED);
426 	if (!link)
427 		return -ENOMEM;
428 #endif
429 	return 0;
430 }
431 
432 int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
433 			const struct dvb_device *template, void *priv, int type,
434 			int demux_sink_pads)
435 {
436 	struct dvb_device *dvbdev;
437 	struct file_operations *dvbdevfops;
438 	struct device *clsdev;
439 	int minor;
440 	int id, ret;
441 
442 	mutex_lock(&dvbdev_register_lock);
443 
444 	if ((id = dvbdev_get_free_id (adap, type)) < 0){
445 		mutex_unlock(&dvbdev_register_lock);
446 		*pdvbdev = NULL;
447 		pr_err("%s: couldn't find free device id\n", __func__);
448 		return -ENFILE;
449 	}
450 
451 	*pdvbdev = dvbdev = kzalloc(sizeof(*dvbdev), GFP_KERNEL);
452 
453 	if (!dvbdev){
454 		mutex_unlock(&dvbdev_register_lock);
455 		return -ENOMEM;
456 	}
457 
458 	dvbdevfops = kzalloc(sizeof(struct file_operations), GFP_KERNEL);
459 
460 	if (!dvbdevfops){
461 		kfree (dvbdev);
462 		mutex_unlock(&dvbdev_register_lock);
463 		return -ENOMEM;
464 	}
465 
466 	memcpy(dvbdev, template, sizeof(struct dvb_device));
467 	dvbdev->type = type;
468 	dvbdev->id = id;
469 	dvbdev->adapter = adap;
470 	dvbdev->priv = priv;
471 	dvbdev->fops = dvbdevfops;
472 	init_waitqueue_head (&dvbdev->wait_queue);
473 
474 	memcpy(dvbdevfops, template->fops, sizeof(struct file_operations));
475 	dvbdevfops->owner = adap->module;
476 
477 	list_add_tail (&dvbdev->list_head, &adap->device_list);
478 
479 	down_write(&minor_rwsem);
480 #ifdef CONFIG_DVB_DYNAMIC_MINORS
481 	for (minor = 0; minor < MAX_DVB_MINORS; minor++)
482 		if (dvb_minors[minor] == NULL)
483 			break;
484 
485 	if (minor == MAX_DVB_MINORS) {
486 		kfree(dvbdevfops);
487 		kfree(dvbdev);
488 		up_write(&minor_rwsem);
489 		mutex_unlock(&dvbdev_register_lock);
490 		return -EINVAL;
491 	}
492 #else
493 	minor = nums2minor(adap->num, type, id);
494 #endif
495 
496 	dvbdev->minor = minor;
497 	dvb_minors[minor] = dvbdev;
498 	up_write(&minor_rwsem);
499 
500 	ret = dvb_register_media_device(dvbdev, type, minor, demux_sink_pads);
501 	if (ret) {
502 		pr_err("%s: dvb_register_media_device failed to create the mediagraph\n",
503 		      __func__);
504 
505 		dvb_media_device_free(dvbdev);
506 		kfree(dvbdevfops);
507 		kfree(dvbdev);
508 		up_write(&minor_rwsem);
509 		mutex_unlock(&dvbdev_register_lock);
510 		return ret;
511 	}
512 
513 	mutex_unlock(&dvbdev_register_lock);
514 
515 	clsdev = device_create(dvb_class, adap->device,
516 			       MKDEV(DVB_MAJOR, minor),
517 			       dvbdev, "dvb%d.%s%d", adap->num, dnames[type], id);
518 	if (IS_ERR(clsdev)) {
519 		pr_err("%s: failed to create device dvb%d.%s%d (%ld)\n",
520 		       __func__, adap->num, dnames[type], id, PTR_ERR(clsdev));
521 		return PTR_ERR(clsdev);
522 	}
523 	dprintk("DVB: register adapter%d/%s%d @ minor: %i (0x%02x)\n",
524 		adap->num, dnames[type], id, minor, minor);
525 
526 	return 0;
527 }
528 EXPORT_SYMBOL(dvb_register_device);
529 
530 
531 void dvb_remove_device(struct dvb_device *dvbdev)
532 {
533 	if (!dvbdev)
534 		return;
535 
536 	down_write(&minor_rwsem);
537 	dvb_minors[dvbdev->minor] = NULL;
538 	up_write(&minor_rwsem);
539 
540 	dvb_media_device_free(dvbdev);
541 
542 	device_destroy(dvb_class, MKDEV(DVB_MAJOR, dvbdev->minor));
543 
544 	list_del (&dvbdev->list_head);
545 }
546 EXPORT_SYMBOL(dvb_remove_device);
547 
548 
549 void dvb_free_device(struct dvb_device *dvbdev)
550 {
551 	if (!dvbdev)
552 		return;
553 
554 	kfree (dvbdev->fops);
555 	kfree (dvbdev);
556 }
557 EXPORT_SYMBOL(dvb_free_device);
558 
559 
560 void dvb_unregister_device(struct dvb_device *dvbdev)
561 {
562 	dvb_remove_device(dvbdev);
563 	dvb_free_device(dvbdev);
564 }
565 EXPORT_SYMBOL(dvb_unregister_device);
566 
567 
568 #ifdef CONFIG_MEDIA_CONTROLLER_DVB
569 
570 static int dvb_create_io_intf_links(struct dvb_adapter *adap,
571 				    struct media_interface *intf,
572 				    char *name)
573 {
574 	struct media_device *mdev = adap->mdev;
575 	struct media_entity *entity;
576 	struct media_link *link;
577 
578 	media_device_for_each_entity(entity, mdev) {
579 		if (entity->function == MEDIA_ENT_F_IO_DTV) {
580 			if (strncmp(entity->name, name, strlen(name)))
581 				continue;
582 			link = media_create_intf_link(entity, intf,
583 						      MEDIA_LNK_FL_ENABLED);
584 			if (!link)
585 				return -ENOMEM;
586 		}
587 	}
588 	return 0;
589 }
590 
591 int dvb_create_media_graph(struct dvb_adapter *adap,
592 			   bool create_rf_connector)
593 {
594 	struct media_device *mdev = adap->mdev;
595 	struct media_entity *entity, *tuner = NULL, *demod = NULL, *conn;
596 	struct media_entity *demux = NULL, *ca = NULL;
597 	struct media_link *link;
598 	struct media_interface *intf;
599 	unsigned demux_pad = 0;
600 	unsigned dvr_pad = 0;
601 	unsigned ntuner = 0, ndemod = 0;
602 	int ret;
603 	static const char *connector_name = "Television";
604 
605 	if (!mdev)
606 		return 0;
607 
608 	media_device_for_each_entity(entity, mdev) {
609 		switch (entity->function) {
610 		case MEDIA_ENT_F_TUNER:
611 			tuner = entity;
612 			ntuner++;
613 			break;
614 		case MEDIA_ENT_F_DTV_DEMOD:
615 			demod = entity;
616 			ndemod++;
617 			break;
618 		case MEDIA_ENT_F_TS_DEMUX:
619 			demux = entity;
620 			break;
621 		case MEDIA_ENT_F_DTV_CA:
622 			ca = entity;
623 			break;
624 		}
625 	}
626 
627 	/*
628 	 * Prepare to signalize to media_create_pad_links() that multiple
629 	 * entities of the same type exists and a 1:n or n:1 links need to be
630 	 * created.
631 	 * NOTE: if both tuner and demod have multiple instances, it is up
632 	 * to the caller driver to create such links.
633 	 */
634 	if (ntuner > 1)
635 		tuner = NULL;
636 	if (ndemod > 1)
637 		demod = NULL;
638 
639 	if (create_rf_connector) {
640 		conn = kzalloc(sizeof(*conn), GFP_KERNEL);
641 		if (!conn)
642 			return -ENOMEM;
643 		adap->conn = conn;
644 
645 		adap->conn_pads = kzalloc(sizeof(*adap->conn_pads), GFP_KERNEL);
646 		if (!adap->conn_pads)
647 			return -ENOMEM;
648 
649 		conn->flags = MEDIA_ENT_FL_CONNECTOR;
650 		conn->function = MEDIA_ENT_F_CONN_RF;
651 		conn->name = connector_name;
652 		adap->conn_pads->flags = MEDIA_PAD_FL_SOURCE;
653 
654 		ret = media_entity_pads_init(conn, 1, adap->conn_pads);
655 		if (ret)
656 			return ret;
657 
658 		ret = media_device_register_entity(mdev, conn);
659 		if (ret)
660 			return ret;
661 
662 		if (!ntuner)
663 			ret = media_create_pad_links(mdev,
664 						     MEDIA_ENT_F_CONN_RF,
665 						     conn, 0,
666 						     MEDIA_ENT_F_DTV_DEMOD,
667 						     demod, 0,
668 						     MEDIA_LNK_FL_ENABLED,
669 						     false);
670 		else
671 			ret = media_create_pad_links(mdev,
672 						     MEDIA_ENT_F_CONN_RF,
673 						     conn, 0,
674 						     MEDIA_ENT_F_TUNER,
675 						     tuner, TUNER_PAD_RF_INPUT,
676 						     MEDIA_LNK_FL_ENABLED,
677 						     false);
678 		if (ret)
679 			return ret;
680 	}
681 
682 	if (ntuner && ndemod) {
683 		ret = media_create_pad_links(mdev,
684 					     MEDIA_ENT_F_TUNER,
685 					     tuner, TUNER_PAD_OUTPUT,
686 					     MEDIA_ENT_F_DTV_DEMOD,
687 					     demod, 0, MEDIA_LNK_FL_ENABLED,
688 					     false);
689 		if (ret)
690 			return ret;
691 	}
692 
693 	if (ndemod && demux) {
694 		ret = media_create_pad_links(mdev,
695 					     MEDIA_ENT_F_DTV_DEMOD,
696 					     demod, 1,
697 					     MEDIA_ENT_F_TS_DEMUX,
698 					     demux, 0, MEDIA_LNK_FL_ENABLED,
699 					     false);
700 		if (ret)
701 			return ret;
702 	}
703 	if (demux && ca) {
704 		ret = media_create_pad_link(demux, 1, ca,
705 					    0, MEDIA_LNK_FL_ENABLED);
706 		if (ret)
707 			return ret;
708 	}
709 
710 	/* Create demux links for each ringbuffer/pad */
711 	if (demux) {
712 		media_device_for_each_entity(entity, mdev) {
713 			if (entity->function == MEDIA_ENT_F_IO_DTV) {
714 				if (!strncmp(entity->name, DVR_TSOUT,
715 				    strlen(DVR_TSOUT))) {
716 					ret = media_create_pad_link(demux,
717 								++dvr_pad,
718 							    entity, 0, 0);
719 					if (ret)
720 						return ret;
721 				}
722 				if (!strncmp(entity->name, DEMUX_TSOUT,
723 				    strlen(DEMUX_TSOUT))) {
724 					ret = media_create_pad_link(demux,
725 							      ++demux_pad,
726 							    entity, 0, 0);
727 					if (ret)
728 						return ret;
729 				}
730 			}
731 		}
732 	}
733 
734 	/* Create interface links for FE->tuner, DVR->demux and CA->ca */
735 	media_device_for_each_intf(intf, mdev) {
736 		if (intf->type == MEDIA_INTF_T_DVB_CA && ca) {
737 			link = media_create_intf_link(ca, intf,
738 						      MEDIA_LNK_FL_ENABLED);
739 			if (!link)
740 				return -ENOMEM;
741 		}
742 
743 		if (intf->type == MEDIA_INTF_T_DVB_FE && tuner) {
744 			link = media_create_intf_link(tuner, intf,
745 						      MEDIA_LNK_FL_ENABLED);
746 			if (!link)
747 				return -ENOMEM;
748 		}
749 #if 0
750 		/*
751 		 * Indirect link - let's not create yet, as we don't know how
752 		 *		   to handle indirect links, nor if this will
753 		 *		   actually be needed.
754 		 */
755 		if (intf->type == MEDIA_INTF_T_DVB_DVR && demux) {
756 			link = media_create_intf_link(demux, intf,
757 						      MEDIA_LNK_FL_ENABLED);
758 			if (!link)
759 				return -ENOMEM;
760 		}
761 #endif
762 		if (intf->type == MEDIA_INTF_T_DVB_DVR) {
763 			ret = dvb_create_io_intf_links(adap, intf, DVR_TSOUT);
764 			if (ret)
765 				return ret;
766 		}
767 		if (intf->type == MEDIA_INTF_T_DVB_DEMUX) {
768 			ret = dvb_create_io_intf_links(adap, intf, DEMUX_TSOUT);
769 			if (ret)
770 				return ret;
771 		}
772 	}
773 	return 0;
774 }
775 EXPORT_SYMBOL_GPL(dvb_create_media_graph);
776 #endif
777 
778 static int dvbdev_check_free_adapter_num(int num)
779 {
780 	struct list_head *entry;
781 	list_for_each(entry, &dvb_adapter_list) {
782 		struct dvb_adapter *adap;
783 		adap = list_entry(entry, struct dvb_adapter, list_head);
784 		if (adap->num == num)
785 			return 0;
786 	}
787 	return 1;
788 }
789 
790 static int dvbdev_get_free_adapter_num (void)
791 {
792 	int num = 0;
793 
794 	while (num < DVB_MAX_ADAPTERS) {
795 		if (dvbdev_check_free_adapter_num(num))
796 			return num;
797 		num++;
798 	}
799 
800 	return -ENFILE;
801 }
802 
803 
804 int dvb_register_adapter(struct dvb_adapter *adap, const char *name,
805 			 struct module *module, struct device *device,
806 			 short *adapter_nums)
807 {
808 	int i, num;
809 
810 	mutex_lock(&dvbdev_register_lock);
811 
812 	for (i = 0; i < DVB_MAX_ADAPTERS; ++i) {
813 		num = adapter_nums[i];
814 		if (num >= 0  &&  num < DVB_MAX_ADAPTERS) {
815 		/* use the one the driver asked for */
816 			if (dvbdev_check_free_adapter_num(num))
817 				break;
818 		} else {
819 			num = dvbdev_get_free_adapter_num();
820 			break;
821 		}
822 		num = -1;
823 	}
824 
825 	if (num < 0) {
826 		mutex_unlock(&dvbdev_register_lock);
827 		return -ENFILE;
828 	}
829 
830 	memset (adap, 0, sizeof(struct dvb_adapter));
831 	INIT_LIST_HEAD (&adap->device_list);
832 
833 	pr_info("DVB: registering new adapter (%s)\n", name);
834 
835 	adap->num = num;
836 	adap->name = name;
837 	adap->module = module;
838 	adap->device = device;
839 	adap->mfe_shared = 0;
840 	adap->mfe_dvbdev = NULL;
841 	mutex_init (&adap->mfe_lock);
842 
843 	list_add_tail (&adap->list_head, &dvb_adapter_list);
844 
845 	mutex_unlock(&dvbdev_register_lock);
846 
847 	return num;
848 }
849 EXPORT_SYMBOL(dvb_register_adapter);
850 
851 
852 int dvb_unregister_adapter(struct dvb_adapter *adap)
853 {
854 	mutex_lock(&dvbdev_register_lock);
855 	list_del (&adap->list_head);
856 	mutex_unlock(&dvbdev_register_lock);
857 	return 0;
858 }
859 EXPORT_SYMBOL(dvb_unregister_adapter);
860 
861 /* if the miracle happens and "generic_usercopy()" is included into
862    the kernel, then this can vanish. please don't make the mistake and
863    define this as video_usercopy(). this will introduce a dependecy
864    to the v4l "videodev.o" module, which is unnecessary for some
865    cards (ie. the budget dvb-cards don't need the v4l module...) */
866 int dvb_usercopy(struct file *file,
867 		     unsigned int cmd, unsigned long arg,
868 		     int (*func)(struct file *file,
869 		     unsigned int cmd, void *arg))
870 {
871 	char    sbuf[128];
872 	void    *mbuf = NULL;
873 	void    *parg = NULL;
874 	int     err  = -EINVAL;
875 
876 	/*  Copy arguments into temp kernel buffer  */
877 	switch (_IOC_DIR(cmd)) {
878 	case _IOC_NONE:
879 		/*
880 		 * For this command, the pointer is actually an integer
881 		 * argument.
882 		 */
883 		parg = (void *) arg;
884 		break;
885 	case _IOC_READ: /* some v4l ioctls are marked wrong ... */
886 	case _IOC_WRITE:
887 	case (_IOC_WRITE | _IOC_READ):
888 		if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
889 			parg = sbuf;
890 		} else {
891 			/* too big to allocate from stack */
892 			mbuf = kmalloc(_IOC_SIZE(cmd), GFP_KERNEL);
893 			if (NULL == mbuf)
894 				return -ENOMEM;
895 			parg = mbuf;
896 		}
897 
898 		err = -EFAULT;
899 		if (copy_from_user(parg, (void __user *)arg, _IOC_SIZE(cmd)))
900 			goto out;
901 		break;
902 	}
903 
904 	/* call driver */
905 	if ((err = func(file, cmd, parg)) == -ENOIOCTLCMD)
906 		err = -ENOTTY;
907 
908 	if (err < 0)
909 		goto out;
910 
911 	/*  Copy results into user buffer  */
912 	switch (_IOC_DIR(cmd))
913 	{
914 	case _IOC_READ:
915 	case (_IOC_WRITE | _IOC_READ):
916 		if (copy_to_user((void __user *)arg, parg, _IOC_SIZE(cmd)))
917 			err = -EFAULT;
918 		break;
919 	}
920 
921 out:
922 	kfree(mbuf);
923 	return err;
924 }
925 
926 static int dvb_uevent(struct device *dev, struct kobj_uevent_env *env)
927 {
928 	struct dvb_device *dvbdev = dev_get_drvdata(dev);
929 
930 	add_uevent_var(env, "DVB_ADAPTER_NUM=%d", dvbdev->adapter->num);
931 	add_uevent_var(env, "DVB_DEVICE_TYPE=%s", dnames[dvbdev->type]);
932 	add_uevent_var(env, "DVB_DEVICE_NUM=%d", dvbdev->id);
933 	return 0;
934 }
935 
936 static char *dvb_devnode(struct device *dev, umode_t *mode)
937 {
938 	struct dvb_device *dvbdev = dev_get_drvdata(dev);
939 
940 	return kasprintf(GFP_KERNEL, "dvb/adapter%d/%s%d",
941 		dvbdev->adapter->num, dnames[dvbdev->type], dvbdev->id);
942 }
943 
944 
945 static int __init init_dvbdev(void)
946 {
947 	int retval;
948 	dev_t dev = MKDEV(DVB_MAJOR, 0);
949 
950 	if ((retval = register_chrdev_region(dev, MAX_DVB_MINORS, "DVB")) != 0) {
951 		pr_err("dvb-core: unable to get major %d\n", DVB_MAJOR);
952 		return retval;
953 	}
954 
955 	cdev_init(&dvb_device_cdev, &dvb_device_fops);
956 	if ((retval = cdev_add(&dvb_device_cdev, dev, MAX_DVB_MINORS)) != 0) {
957 		pr_err("dvb-core: unable register character device\n");
958 		goto error;
959 	}
960 
961 	dvb_class = class_create(THIS_MODULE, "dvb");
962 	if (IS_ERR(dvb_class)) {
963 		retval = PTR_ERR(dvb_class);
964 		goto error;
965 	}
966 	dvb_class->dev_uevent = dvb_uevent;
967 	dvb_class->devnode = dvb_devnode;
968 	return 0;
969 
970 error:
971 	cdev_del(&dvb_device_cdev);
972 	unregister_chrdev_region(dev, MAX_DVB_MINORS);
973 	return retval;
974 }
975 
976 
977 static void __exit exit_dvbdev(void)
978 {
979 	class_destroy(dvb_class);
980 	cdev_del(&dvb_device_cdev);
981 	unregister_chrdev_region(MKDEV(DVB_MAJOR, 0), MAX_DVB_MINORS);
982 }
983 
984 subsys_initcall(init_dvbdev);
985 module_exit(exit_dvbdev);
986 
987 MODULE_DESCRIPTION("DVB Core Driver");
988 MODULE_AUTHOR("Marcus Metzler, Ralph Metzler, Holger Waechtler");
989 MODULE_LICENSE("GPL");
990