xref: /linux/drivers/media/dvb-core/dvbdev.c (revision 0883c2c06fb5bcf5b9e008270827e63c09a88c1e)
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 /* Due to enum tuner_pad_index */
38 #include <media/tuner.h>
39 
40 static DEFINE_MUTEX(dvbdev_mutex);
41 static int dvbdev_debug;
42 
43 module_param(dvbdev_debug, int, 0644);
44 MODULE_PARM_DESC(dvbdev_debug, "Turn on/off device debugging (default:off).");
45 
46 #define dprintk if (dvbdev_debug) printk
47 
48 static LIST_HEAD(dvb_adapter_list);
49 static DEFINE_MUTEX(dvbdev_register_lock);
50 
51 static const char * const dnames[] = {
52 	"video", "audio", "sec", "frontend", "demux", "dvr", "ca",
53 	"net", "osd"
54 };
55 
56 #ifdef CONFIG_DVB_DYNAMIC_MINORS
57 #define MAX_DVB_MINORS		256
58 #define DVB_MAX_IDS		MAX_DVB_MINORS
59 #else
60 #define DVB_MAX_IDS		4
61 #define nums2minor(num, type, id)	((num << 6) | (id << 4) | type)
62 #define MAX_DVB_MINORS		(DVB_MAX_ADAPTERS*64)
63 #endif
64 
65 static struct class *dvb_class;
66 
67 static struct dvb_device *dvb_minors[MAX_DVB_MINORS];
68 static DECLARE_RWSEM(minor_rwsem);
69 
70 static int dvb_device_open(struct inode *inode, struct file *file)
71 {
72 	struct dvb_device *dvbdev;
73 
74 	mutex_lock(&dvbdev_mutex);
75 	down_read(&minor_rwsem);
76 	dvbdev = dvb_minors[iminor(inode)];
77 
78 	if (dvbdev && dvbdev->fops) {
79 		int err = 0;
80 		const struct file_operations *new_fops;
81 
82 		new_fops = fops_get(dvbdev->fops);
83 		if (!new_fops)
84 			goto fail;
85 		file->private_data = dvbdev;
86 		replace_fops(file, new_fops);
87 		if (file->f_op->open)
88 			err = file->f_op->open(inode, file);
89 		up_read(&minor_rwsem);
90 		mutex_unlock(&dvbdev_mutex);
91 		return err;
92 	}
93 fail:
94 	up_read(&minor_rwsem);
95 	mutex_unlock(&dvbdev_mutex);
96 	return -ENODEV;
97 }
98 
99 
100 static const struct file_operations dvb_device_fops =
101 {
102 	.owner =	THIS_MODULE,
103 	.open =		dvb_device_open,
104 	.llseek =	noop_llseek,
105 };
106 
107 static struct cdev dvb_device_cdev;
108 
109 int dvb_generic_open(struct inode *inode, struct file *file)
110 {
111 	struct dvb_device *dvbdev = file->private_data;
112 
113 	if (!dvbdev)
114 		return -ENODEV;
115 
116 	if (!dvbdev->users)
117 		return -EBUSY;
118 
119 	if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
120 		if (!dvbdev->readers)
121 			return -EBUSY;
122 		dvbdev->readers--;
123 	} else {
124 		if (!dvbdev->writers)
125 			return -EBUSY;
126 		dvbdev->writers--;
127 	}
128 
129 	dvbdev->users--;
130 	return 0;
131 }
132 EXPORT_SYMBOL(dvb_generic_open);
133 
134 
135 int dvb_generic_release(struct inode *inode, struct file *file)
136 {
137 	struct dvb_device *dvbdev = file->private_data;
138 
139 	if (!dvbdev)
140 		return -ENODEV;
141 
142 	if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
143 		dvbdev->readers++;
144 	} else {
145 		dvbdev->writers++;
146 	}
147 
148 	dvbdev->users++;
149 	return 0;
150 }
151 EXPORT_SYMBOL(dvb_generic_release);
152 
153 
154 long dvb_generic_ioctl(struct file *file,
155 		       unsigned int cmd, unsigned long arg)
156 {
157 	struct dvb_device *dvbdev = file->private_data;
158 
159 	if (!dvbdev)
160 		return -ENODEV;
161 
162 	if (!dvbdev->kernel_ioctl)
163 		return -EINVAL;
164 
165 	return dvb_usercopy(file, cmd, arg, dvbdev->kernel_ioctl);
166 }
167 EXPORT_SYMBOL(dvb_generic_ioctl);
168 
169 
170 static int dvbdev_get_free_id (struct dvb_adapter *adap, int type)
171 {
172 	u32 id = 0;
173 
174 	while (id < DVB_MAX_IDS) {
175 		struct dvb_device *dev;
176 		list_for_each_entry(dev, &adap->device_list, list_head)
177 			if (dev->type == type && dev->id == id)
178 				goto skip;
179 		return id;
180 skip:
181 		id++;
182 	}
183 	return -ENFILE;
184 }
185 
186 static void dvb_media_device_free(struct dvb_device *dvbdev)
187 {
188 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
189 	if (dvbdev->entity) {
190 		media_device_unregister_entity(dvbdev->entity);
191 		kfree(dvbdev->entity);
192 		kfree(dvbdev->pads);
193 		dvbdev->entity = NULL;
194 		dvbdev->pads = NULL;
195 	}
196 
197 	if (dvbdev->tsout_entity) {
198 		int i;
199 
200 		for (i = 0; i < dvbdev->tsout_num_entities; i++) {
201 			media_device_unregister_entity(&dvbdev->tsout_entity[i]);
202 			kfree(dvbdev->tsout_entity[i].name);
203 		}
204 		kfree(dvbdev->tsout_entity);
205 		kfree(dvbdev->tsout_pads);
206 		dvbdev->tsout_entity = NULL;
207 		dvbdev->tsout_pads = NULL;
208 
209 		dvbdev->tsout_num_entities = 0;
210 	}
211 
212 	if (dvbdev->intf_devnode) {
213 		media_devnode_remove(dvbdev->intf_devnode);
214 		dvbdev->intf_devnode = NULL;
215 	}
216 
217 	if (dvbdev->adapter->conn) {
218 		media_device_unregister_entity(dvbdev->adapter->conn);
219 		dvbdev->adapter->conn = NULL;
220 		kfree(dvbdev->adapter->conn_pads);
221 		dvbdev->adapter->conn_pads = NULL;
222 	}
223 #endif
224 }
225 
226 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
227 static int dvb_create_tsout_entity(struct dvb_device *dvbdev,
228 				    const char *name, int npads)
229 {
230 	int i, ret = 0;
231 
232 	dvbdev->tsout_pads = kcalloc(npads, sizeof(*dvbdev->tsout_pads),
233 				     GFP_KERNEL);
234 	if (!dvbdev->tsout_pads)
235 		return -ENOMEM;
236 
237 	dvbdev->tsout_entity = kcalloc(npads, sizeof(*dvbdev->tsout_entity),
238 				       GFP_KERNEL);
239 	if (!dvbdev->tsout_entity)
240 		return -ENOMEM;
241 
242 	dvbdev->tsout_num_entities = npads;
243 
244 	for (i = 0; i < npads; i++) {
245 		struct media_pad *pads = &dvbdev->tsout_pads[i];
246 		struct media_entity *entity = &dvbdev->tsout_entity[i];
247 
248 		entity->name = kasprintf(GFP_KERNEL, "%s #%d", name, i);
249 		if (!entity->name)
250 			return -ENOMEM;
251 
252 		entity->function = MEDIA_ENT_F_IO_DTV;
253 		pads->flags = MEDIA_PAD_FL_SINK;
254 
255 		ret = media_entity_pads_init(entity, 1, pads);
256 		if (ret < 0)
257 			return ret;
258 
259 		ret = media_device_register_entity(dvbdev->adapter->mdev,
260 						   entity);
261 		if (ret < 0)
262 			return ret;
263 	}
264 	return 0;
265 }
266 
267 #define DEMUX_TSOUT	"demux-tsout"
268 #define DVR_TSOUT	"dvr-tsout"
269 
270 static int dvb_create_media_entity(struct dvb_device *dvbdev,
271 				   int type, int demux_sink_pads)
272 {
273 	int i, ret, npads;
274 
275 	switch (type) {
276 	case DVB_DEVICE_FRONTEND:
277 		npads = 2;
278 		break;
279 	case DVB_DEVICE_DVR:
280 		ret = dvb_create_tsout_entity(dvbdev, DVR_TSOUT,
281 					      demux_sink_pads);
282 		return ret;
283 	case DVB_DEVICE_DEMUX:
284 		npads = 1 + demux_sink_pads;
285 		ret = dvb_create_tsout_entity(dvbdev, DEMUX_TSOUT,
286 					      demux_sink_pads);
287 		if (ret < 0)
288 			return ret;
289 		break;
290 	case DVB_DEVICE_CA:
291 		npads = 2;
292 		break;
293 	case DVB_DEVICE_NET:
294 		/*
295 		 * We should be creating entities for the MPE/ULE
296 		 * decapsulation hardware (or software implementation).
297 		 *
298 		 * However, the number of for the MPE/ULE decaps may not be
299 		 * fixed. As we don't have yet dynamic support for PADs at
300 		 * the Media Controller, let's not create the decap
301 		 * entities yet.
302 		 */
303 		return 0;
304 	default:
305 		return 0;
306 	}
307 
308 	dvbdev->entity = kzalloc(sizeof(*dvbdev->entity), GFP_KERNEL);
309 	if (!dvbdev->entity)
310 		return -ENOMEM;
311 
312 	dvbdev->entity->name = dvbdev->name;
313 
314 	if (npads) {
315 		dvbdev->pads = kcalloc(npads, sizeof(*dvbdev->pads),
316 				       GFP_KERNEL);
317 		if (!dvbdev->pads)
318 			return -ENOMEM;
319 	}
320 
321 	switch (type) {
322 	case DVB_DEVICE_FRONTEND:
323 		dvbdev->entity->function = MEDIA_ENT_F_DTV_DEMOD;
324 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
325 		dvbdev->pads[1].flags = MEDIA_PAD_FL_SOURCE;
326 		break;
327 	case DVB_DEVICE_DEMUX:
328 		dvbdev->entity->function = MEDIA_ENT_F_TS_DEMUX;
329 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
330 		for (i = 1; i < npads; i++)
331 			dvbdev->pads[i].flags = MEDIA_PAD_FL_SOURCE;
332 		break;
333 	case DVB_DEVICE_CA:
334 		dvbdev->entity->function = MEDIA_ENT_F_DTV_CA;
335 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
336 		dvbdev->pads[1].flags = MEDIA_PAD_FL_SOURCE;
337 		break;
338 	default:
339 		/* Should never happen, as the first switch prevents it */
340 		kfree(dvbdev->entity);
341 		kfree(dvbdev->pads);
342 		dvbdev->entity = NULL;
343 		dvbdev->pads = NULL;
344 		return 0;
345 	}
346 
347 	if (npads) {
348 		ret = media_entity_pads_init(dvbdev->entity, npads, dvbdev->pads);
349 		if (ret)
350 			return ret;
351 	}
352 	ret = media_device_register_entity(dvbdev->adapter->mdev,
353 					   dvbdev->entity);
354 	if (ret)
355 		return ret;
356 
357 	printk(KERN_DEBUG "%s: media entity '%s' registered.\n",
358 		__func__, dvbdev->entity->name);
359 
360 	return 0;
361 }
362 #endif
363 
364 static int dvb_register_media_device(struct dvb_device *dvbdev,
365 				     int type, int minor,
366 				     unsigned demux_sink_pads)
367 {
368 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
369 	struct media_link *link;
370 	u32 intf_type;
371 	int ret;
372 
373 	if (!dvbdev->adapter->mdev)
374 		return 0;
375 
376 	ret = dvb_create_media_entity(dvbdev, type, demux_sink_pads);
377 	if (ret)
378 		return ret;
379 
380 	switch (type) {
381 	case DVB_DEVICE_FRONTEND:
382 		intf_type = MEDIA_INTF_T_DVB_FE;
383 		break;
384 	case DVB_DEVICE_DEMUX:
385 		intf_type = MEDIA_INTF_T_DVB_DEMUX;
386 		break;
387 	case DVB_DEVICE_DVR:
388 		intf_type = MEDIA_INTF_T_DVB_DVR;
389 		break;
390 	case DVB_DEVICE_CA:
391 		intf_type = MEDIA_INTF_T_DVB_CA;
392 		break;
393 	case DVB_DEVICE_NET:
394 		intf_type = MEDIA_INTF_T_DVB_NET;
395 		break;
396 	default:
397 		return 0;
398 	}
399 
400 	dvbdev->intf_devnode = media_devnode_create(dvbdev->adapter->mdev,
401 						    intf_type, 0,
402 						    DVB_MAJOR, minor);
403 
404 	if (!dvbdev->intf_devnode)
405 		return -ENOMEM;
406 
407 	/*
408 	 * Create the "obvious" link, e. g. the ones that represent
409 	 * a direct association between an interface and an entity.
410 	 * Other links should be created elsewhere, like:
411 	 *		DVB FE intf    -> tuner
412 	 *		DVB demux intf -> dvr
413 	 */
414 
415 	if (!dvbdev->entity)
416 		return 0;
417 
418 	link = media_create_intf_link(dvbdev->entity, &dvbdev->intf_devnode->intf,
419 				      MEDIA_LNK_FL_ENABLED);
420 	if (!link)
421 		return -ENOMEM;
422 #endif
423 	return 0;
424 }
425 
426 int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
427 			const struct dvb_device *template, void *priv, int type,
428 			int demux_sink_pads)
429 {
430 	struct dvb_device *dvbdev;
431 	struct file_operations *dvbdevfops;
432 	struct device *clsdev;
433 	int minor;
434 	int id, ret;
435 
436 	mutex_lock(&dvbdev_register_lock);
437 
438 	if ((id = dvbdev_get_free_id (adap, type)) < 0){
439 		mutex_unlock(&dvbdev_register_lock);
440 		*pdvbdev = NULL;
441 		printk(KERN_ERR "%s: couldn't find free device id\n", __func__);
442 		return -ENFILE;
443 	}
444 
445 	*pdvbdev = dvbdev = kzalloc(sizeof(*dvbdev), GFP_KERNEL);
446 
447 	if (!dvbdev){
448 		mutex_unlock(&dvbdev_register_lock);
449 		return -ENOMEM;
450 	}
451 
452 	dvbdevfops = kzalloc(sizeof(struct file_operations), GFP_KERNEL);
453 
454 	if (!dvbdevfops){
455 		kfree (dvbdev);
456 		mutex_unlock(&dvbdev_register_lock);
457 		return -ENOMEM;
458 	}
459 
460 	memcpy(dvbdev, template, sizeof(struct dvb_device));
461 	dvbdev->type = type;
462 	dvbdev->id = id;
463 	dvbdev->adapter = adap;
464 	dvbdev->priv = priv;
465 	dvbdev->fops = dvbdevfops;
466 	init_waitqueue_head (&dvbdev->wait_queue);
467 
468 	memcpy(dvbdevfops, template->fops, sizeof(struct file_operations));
469 	dvbdevfops->owner = adap->module;
470 
471 	list_add_tail (&dvbdev->list_head, &adap->device_list);
472 
473 	down_write(&minor_rwsem);
474 #ifdef CONFIG_DVB_DYNAMIC_MINORS
475 	for (minor = 0; minor < MAX_DVB_MINORS; minor++)
476 		if (dvb_minors[minor] == NULL)
477 			break;
478 
479 	if (minor == MAX_DVB_MINORS) {
480 		kfree(dvbdevfops);
481 		kfree(dvbdev);
482 		up_write(&minor_rwsem);
483 		mutex_unlock(&dvbdev_register_lock);
484 		return -EINVAL;
485 	}
486 #else
487 	minor = nums2minor(adap->num, type, id);
488 #endif
489 
490 	dvbdev->minor = minor;
491 	dvb_minors[minor] = dvbdev;
492 	up_write(&minor_rwsem);
493 
494 	ret = dvb_register_media_device(dvbdev, type, minor, demux_sink_pads);
495 	if (ret) {
496 		printk(KERN_ERR
497 		      "%s: dvb_register_media_device failed to create the mediagraph\n",
498 		      __func__);
499 
500 		dvb_media_device_free(dvbdev);
501 		kfree(dvbdevfops);
502 		kfree(dvbdev);
503 		up_write(&minor_rwsem);
504 		mutex_unlock(&dvbdev_register_lock);
505 		return ret;
506 	}
507 
508 	mutex_unlock(&dvbdev_register_lock);
509 
510 	clsdev = device_create(dvb_class, adap->device,
511 			       MKDEV(DVB_MAJOR, minor),
512 			       dvbdev, "dvb%d.%s%d", adap->num, dnames[type], id);
513 	if (IS_ERR(clsdev)) {
514 		printk(KERN_ERR "%s: failed to create device dvb%d.%s%d (%ld)\n",
515 		       __func__, adap->num, dnames[type], id, PTR_ERR(clsdev));
516 		return PTR_ERR(clsdev);
517 	}
518 	dprintk(KERN_DEBUG "DVB: register adapter%d/%s%d @ minor: %i (0x%02x)\n",
519 		adap->num, dnames[type], id, minor, minor);
520 
521 	return 0;
522 }
523 EXPORT_SYMBOL(dvb_register_device);
524 
525 
526 void dvb_unregister_device(struct dvb_device *dvbdev)
527 {
528 	if (!dvbdev)
529 		return;
530 
531 	down_write(&minor_rwsem);
532 	dvb_minors[dvbdev->minor] = NULL;
533 	up_write(&minor_rwsem);
534 
535 	dvb_media_device_free(dvbdev);
536 
537 	device_destroy(dvb_class, MKDEV(DVB_MAJOR, dvbdev->minor));
538 
539 	list_del (&dvbdev->list_head);
540 	kfree (dvbdev->fops);
541 	kfree (dvbdev);
542 }
543 EXPORT_SYMBOL(dvb_unregister_device);
544 
545 
546 #ifdef CONFIG_MEDIA_CONTROLLER_DVB
547 
548 static int dvb_create_io_intf_links(struct dvb_adapter *adap,
549 				    struct media_interface *intf,
550 				    char *name)
551 {
552 	struct media_device *mdev = adap->mdev;
553 	struct media_entity *entity;
554 	struct media_link *link;
555 
556 	media_device_for_each_entity(entity, mdev) {
557 		if (entity->function == MEDIA_ENT_F_IO_DTV) {
558 			if (strncmp(entity->name, name, strlen(name)))
559 				continue;
560 			link = media_create_intf_link(entity, intf,
561 						      MEDIA_LNK_FL_ENABLED);
562 			if (!link)
563 				return -ENOMEM;
564 		}
565 	}
566 	return 0;
567 }
568 
569 int dvb_create_media_graph(struct dvb_adapter *adap,
570 			   bool create_rf_connector)
571 {
572 	struct media_device *mdev = adap->mdev;
573 	struct media_entity *entity, *tuner = NULL, *demod = NULL, *conn;
574 	struct media_entity *demux = NULL, *ca = NULL;
575 	struct media_link *link;
576 	struct media_interface *intf;
577 	unsigned demux_pad = 0;
578 	unsigned dvr_pad = 0;
579 	unsigned ntuner = 0, ndemod = 0;
580 	int ret;
581 	static const char *connector_name = "Television";
582 
583 	if (!mdev)
584 		return 0;
585 
586 	media_device_for_each_entity(entity, mdev) {
587 		switch (entity->function) {
588 		case MEDIA_ENT_F_TUNER:
589 			tuner = entity;
590 			ntuner++;
591 			break;
592 		case MEDIA_ENT_F_DTV_DEMOD:
593 			demod = entity;
594 			ndemod++;
595 			break;
596 		case MEDIA_ENT_F_TS_DEMUX:
597 			demux = entity;
598 			break;
599 		case MEDIA_ENT_F_DTV_CA:
600 			ca = entity;
601 			break;
602 		}
603 	}
604 
605 	/*
606 	 * Prepare to signalize to media_create_pad_links() that multiple
607 	 * entities of the same type exists and a 1:n or n:1 links need to be
608 	 * created.
609 	 * NOTE: if both tuner and demod have multiple instances, it is up
610 	 * to the caller driver to create such links.
611 	 */
612 	if (ntuner > 1)
613 		tuner = NULL;
614 	if (ndemod > 1)
615 		demod = NULL;
616 
617 	if (create_rf_connector) {
618 		conn = kzalloc(sizeof(*conn), GFP_KERNEL);
619 		if (!conn)
620 			return -ENOMEM;
621 		adap->conn = conn;
622 
623 		adap->conn_pads = kzalloc(sizeof(*adap->conn_pads), GFP_KERNEL);
624 		if (!adap->conn_pads)
625 			return -ENOMEM;
626 
627 		conn->flags = MEDIA_ENT_FL_CONNECTOR;
628 		conn->function = MEDIA_ENT_F_CONN_RF;
629 		conn->name = connector_name;
630 		adap->conn_pads->flags = MEDIA_PAD_FL_SOURCE;
631 
632 		ret = media_entity_pads_init(conn, 1, adap->conn_pads);
633 		if (ret)
634 			return ret;
635 
636 		ret = media_device_register_entity(mdev, conn);
637 		if (ret)
638 			return ret;
639 
640 		if (!ntuner)
641 			ret = media_create_pad_links(mdev,
642 						     MEDIA_ENT_F_CONN_RF,
643 						     conn, 0,
644 						     MEDIA_ENT_F_DTV_DEMOD,
645 						     demod, 0,
646 						     MEDIA_LNK_FL_ENABLED,
647 						     false);
648 		else
649 			ret = media_create_pad_links(mdev,
650 						     MEDIA_ENT_F_CONN_RF,
651 						     conn, 0,
652 						     MEDIA_ENT_F_TUNER,
653 						     tuner, TUNER_PAD_RF_INPUT,
654 						     MEDIA_LNK_FL_ENABLED,
655 						     false);
656 		if (ret)
657 			return ret;
658 	}
659 
660 	if (ntuner && ndemod) {
661 		ret = media_create_pad_links(mdev,
662 					     MEDIA_ENT_F_TUNER,
663 					     tuner, TUNER_PAD_OUTPUT,
664 					     MEDIA_ENT_F_DTV_DEMOD,
665 					     demod, 0, MEDIA_LNK_FL_ENABLED,
666 					     false);
667 		if (ret)
668 			return ret;
669 	}
670 
671 	if (ndemod && demux) {
672 		ret = media_create_pad_links(mdev,
673 					     MEDIA_ENT_F_DTV_DEMOD,
674 					     demod, 1,
675 					     MEDIA_ENT_F_TS_DEMUX,
676 					     demux, 0, MEDIA_LNK_FL_ENABLED,
677 					     false);
678 		if (ret)
679 			return ret;
680 	}
681 	if (demux && ca) {
682 		ret = media_create_pad_link(demux, 1, ca,
683 					    0, MEDIA_LNK_FL_ENABLED);
684 		if (ret)
685 			return ret;
686 	}
687 
688 	/* Create demux links for each ringbuffer/pad */
689 	if (demux) {
690 		media_device_for_each_entity(entity, mdev) {
691 			if (entity->function == MEDIA_ENT_F_IO_DTV) {
692 				if (!strncmp(entity->name, DVR_TSOUT,
693 				    strlen(DVR_TSOUT))) {
694 					ret = media_create_pad_link(demux,
695 								++dvr_pad,
696 							    entity, 0, 0);
697 					if (ret)
698 						return ret;
699 				}
700 				if (!strncmp(entity->name, DEMUX_TSOUT,
701 				    strlen(DEMUX_TSOUT))) {
702 					ret = media_create_pad_link(demux,
703 							      ++demux_pad,
704 							    entity, 0, 0);
705 					if (ret)
706 						return ret;
707 				}
708 			}
709 		}
710 	}
711 
712 	/* Create interface links for FE->tuner, DVR->demux and CA->ca */
713 	media_device_for_each_intf(intf, mdev) {
714 		if (intf->type == MEDIA_INTF_T_DVB_CA && ca) {
715 			link = media_create_intf_link(ca, intf,
716 						      MEDIA_LNK_FL_ENABLED);
717 			if (!link)
718 				return -ENOMEM;
719 		}
720 
721 		if (intf->type == MEDIA_INTF_T_DVB_FE && tuner) {
722 			link = media_create_intf_link(tuner, intf,
723 						      MEDIA_LNK_FL_ENABLED);
724 			if (!link)
725 				return -ENOMEM;
726 		}
727 #if 0
728 		/*
729 		 * Indirect link - let's not create yet, as we don't know how
730 		 *		   to handle indirect links, nor if this will
731 		 *		   actually be needed.
732 		 */
733 		if (intf->type == MEDIA_INTF_T_DVB_DVR && demux) {
734 			link = media_create_intf_link(demux, intf,
735 						      MEDIA_LNK_FL_ENABLED);
736 			if (!link)
737 				return -ENOMEM;
738 		}
739 #endif
740 		if (intf->type == MEDIA_INTF_T_DVB_DVR) {
741 			ret = dvb_create_io_intf_links(adap, intf, DVR_TSOUT);
742 			if (ret)
743 				return ret;
744 		}
745 		if (intf->type == MEDIA_INTF_T_DVB_DEMUX) {
746 			ret = dvb_create_io_intf_links(adap, intf, DEMUX_TSOUT);
747 			if (ret)
748 				return ret;
749 		}
750 	}
751 	return 0;
752 }
753 EXPORT_SYMBOL_GPL(dvb_create_media_graph);
754 #endif
755 
756 static int dvbdev_check_free_adapter_num(int num)
757 {
758 	struct list_head *entry;
759 	list_for_each(entry, &dvb_adapter_list) {
760 		struct dvb_adapter *adap;
761 		adap = list_entry(entry, struct dvb_adapter, list_head);
762 		if (adap->num == num)
763 			return 0;
764 	}
765 	return 1;
766 }
767 
768 static int dvbdev_get_free_adapter_num (void)
769 {
770 	int num = 0;
771 
772 	while (num < DVB_MAX_ADAPTERS) {
773 		if (dvbdev_check_free_adapter_num(num))
774 			return num;
775 		num++;
776 	}
777 
778 	return -ENFILE;
779 }
780 
781 
782 int dvb_register_adapter(struct dvb_adapter *adap, const char *name,
783 			 struct module *module, struct device *device,
784 			 short *adapter_nums)
785 {
786 	int i, num;
787 
788 	mutex_lock(&dvbdev_register_lock);
789 
790 	for (i = 0; i < DVB_MAX_ADAPTERS; ++i) {
791 		num = adapter_nums[i];
792 		if (num >= 0  &&  num < DVB_MAX_ADAPTERS) {
793 		/* use the one the driver asked for */
794 			if (dvbdev_check_free_adapter_num(num))
795 				break;
796 		} else {
797 			num = dvbdev_get_free_adapter_num();
798 			break;
799 		}
800 		num = -1;
801 	}
802 
803 	if (num < 0) {
804 		mutex_unlock(&dvbdev_register_lock);
805 		return -ENFILE;
806 	}
807 
808 	memset (adap, 0, sizeof(struct dvb_adapter));
809 	INIT_LIST_HEAD (&adap->device_list);
810 
811 	printk(KERN_INFO "DVB: registering new adapter (%s)\n", name);
812 
813 	adap->num = num;
814 	adap->name = name;
815 	adap->module = module;
816 	adap->device = device;
817 	adap->mfe_shared = 0;
818 	adap->mfe_dvbdev = NULL;
819 	mutex_init (&adap->mfe_lock);
820 
821 	list_add_tail (&adap->list_head, &dvb_adapter_list);
822 
823 	mutex_unlock(&dvbdev_register_lock);
824 
825 	return num;
826 }
827 EXPORT_SYMBOL(dvb_register_adapter);
828 
829 
830 int dvb_unregister_adapter(struct dvb_adapter *adap)
831 {
832 	mutex_lock(&dvbdev_register_lock);
833 	list_del (&adap->list_head);
834 	mutex_unlock(&dvbdev_register_lock);
835 	return 0;
836 }
837 EXPORT_SYMBOL(dvb_unregister_adapter);
838 
839 /* if the miracle happens and "generic_usercopy()" is included into
840    the kernel, then this can vanish. please don't make the mistake and
841    define this as video_usercopy(). this will introduce a dependecy
842    to the v4l "videodev.o" module, which is unnecessary for some
843    cards (ie. the budget dvb-cards don't need the v4l module...) */
844 int dvb_usercopy(struct file *file,
845 		     unsigned int cmd, unsigned long arg,
846 		     int (*func)(struct file *file,
847 		     unsigned int cmd, void *arg))
848 {
849 	char    sbuf[128];
850 	void    *mbuf = NULL;
851 	void    *parg = NULL;
852 	int     err  = -EINVAL;
853 
854 	/*  Copy arguments into temp kernel buffer  */
855 	switch (_IOC_DIR(cmd)) {
856 	case _IOC_NONE:
857 		/*
858 		 * For this command, the pointer is actually an integer
859 		 * argument.
860 		 */
861 		parg = (void *) arg;
862 		break;
863 	case _IOC_READ: /* some v4l ioctls are marked wrong ... */
864 	case _IOC_WRITE:
865 	case (_IOC_WRITE | _IOC_READ):
866 		if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
867 			parg = sbuf;
868 		} else {
869 			/* too big to allocate from stack */
870 			mbuf = kmalloc(_IOC_SIZE(cmd), GFP_KERNEL);
871 			if (NULL == mbuf)
872 				return -ENOMEM;
873 			parg = mbuf;
874 		}
875 
876 		err = -EFAULT;
877 		if (copy_from_user(parg, (void __user *)arg, _IOC_SIZE(cmd)))
878 			goto out;
879 		break;
880 	}
881 
882 	/* call driver */
883 	if ((err = func(file, cmd, parg)) == -ENOIOCTLCMD)
884 		err = -ENOTTY;
885 
886 	if (err < 0)
887 		goto out;
888 
889 	/*  Copy results into user buffer  */
890 	switch (_IOC_DIR(cmd))
891 	{
892 	case _IOC_READ:
893 	case (_IOC_WRITE | _IOC_READ):
894 		if (copy_to_user((void __user *)arg, parg, _IOC_SIZE(cmd)))
895 			err = -EFAULT;
896 		break;
897 	}
898 
899 out:
900 	kfree(mbuf);
901 	return err;
902 }
903 
904 static int dvb_uevent(struct device *dev, struct kobj_uevent_env *env)
905 {
906 	struct dvb_device *dvbdev = dev_get_drvdata(dev);
907 
908 	add_uevent_var(env, "DVB_ADAPTER_NUM=%d", dvbdev->adapter->num);
909 	add_uevent_var(env, "DVB_DEVICE_TYPE=%s", dnames[dvbdev->type]);
910 	add_uevent_var(env, "DVB_DEVICE_NUM=%d", dvbdev->id);
911 	return 0;
912 }
913 
914 static char *dvb_devnode(struct device *dev, umode_t *mode)
915 {
916 	struct dvb_device *dvbdev = dev_get_drvdata(dev);
917 
918 	return kasprintf(GFP_KERNEL, "dvb/adapter%d/%s%d",
919 		dvbdev->adapter->num, dnames[dvbdev->type], dvbdev->id);
920 }
921 
922 
923 static int __init init_dvbdev(void)
924 {
925 	int retval;
926 	dev_t dev = MKDEV(DVB_MAJOR, 0);
927 
928 	if ((retval = register_chrdev_region(dev, MAX_DVB_MINORS, "DVB")) != 0) {
929 		printk(KERN_ERR "dvb-core: unable to get major %d\n", DVB_MAJOR);
930 		return retval;
931 	}
932 
933 	cdev_init(&dvb_device_cdev, &dvb_device_fops);
934 	if ((retval = cdev_add(&dvb_device_cdev, dev, MAX_DVB_MINORS)) != 0) {
935 		printk(KERN_ERR "dvb-core: unable register character device\n");
936 		goto error;
937 	}
938 
939 	dvb_class = class_create(THIS_MODULE, "dvb");
940 	if (IS_ERR(dvb_class)) {
941 		retval = PTR_ERR(dvb_class);
942 		goto error;
943 	}
944 	dvb_class->dev_uevent = dvb_uevent;
945 	dvb_class->devnode = dvb_devnode;
946 	return 0;
947 
948 error:
949 	cdev_del(&dvb_device_cdev);
950 	unregister_chrdev_region(dev, MAX_DVB_MINORS);
951 	return retval;
952 }
953 
954 
955 static void __exit exit_dvbdev(void)
956 {
957 	class_destroy(dvb_class);
958 	cdev_del(&dvb_device_cdev);
959 	unregister_chrdev_region(MKDEV(DVB_MAJOR, 0), MAX_DVB_MINORS);
960 }
961 
962 subsys_initcall(init_dvbdev);
963 module_exit(exit_dvbdev);
964 
965 MODULE_DESCRIPTION("DVB Core Driver");
966 MODULE_AUTHOR("Marcus Metzler, Ralph Metzler, Holger Waechtler");
967 MODULE_LICENSE("GPL");
968