xref: /openbmc/linux/drivers/media/dvb-core/dvbdev.c (revision 4f6cce39)
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  */
19 
20 #define pr_fmt(fmt) "dvbdev: " fmt
21 
22 #include <linux/types.h>
23 #include <linux/errno.h>
24 #include <linux/string.h>
25 #include <linux/module.h>
26 #include <linux/kernel.h>
27 #include <linux/init.h>
28 #include <linux/slab.h>
29 #include <linux/device.h>
30 #include <linux/fs.h>
31 #include <linux/cdev.h>
32 #include <linux/mutex.h>
33 #include "dvbdev.h"
34 
35 /* Due to enum tuner_pad_index */
36 #include <media/tuner.h>
37 
38 static DEFINE_MUTEX(dvbdev_mutex);
39 static int dvbdev_debug;
40 
41 module_param(dvbdev_debug, int, 0644);
42 MODULE_PARM_DESC(dvbdev_debug, "Turn on/off device debugging (default:off).");
43 
44 #define dprintk(fmt, arg...) do {					\
45 	if (dvbdev_debug)						\
46 		printk(KERN_DEBUG pr_fmt("%s: " fmt),			\
47 		       __func__, ##arg);				\
48 } while (0)
49 
50 static LIST_HEAD(dvb_adapter_list);
51 static DEFINE_MUTEX(dvbdev_register_lock);
52 
53 static const char * const dnames[] = {
54 	"video", "audio", "sec", "frontend", "demux", "dvr", "ca",
55 	"net", "osd"
56 };
57 
58 #ifdef CONFIG_DVB_DYNAMIC_MINORS
59 #define MAX_DVB_MINORS		256
60 #define DVB_MAX_IDS		MAX_DVB_MINORS
61 #else
62 #define DVB_MAX_IDS		4
63 #define nums2minor(num, type, id)	((num << 6) | (id << 4) | type)
64 #define MAX_DVB_MINORS		(DVB_MAX_ADAPTERS*64)
65 #endif
66 
67 static struct class *dvb_class;
68 
69 static struct dvb_device *dvb_minors[MAX_DVB_MINORS];
70 static DECLARE_RWSEM(minor_rwsem);
71 
72 static int dvb_device_open(struct inode *inode, struct file *file)
73 {
74 	struct dvb_device *dvbdev;
75 
76 	mutex_lock(&dvbdev_mutex);
77 	down_read(&minor_rwsem);
78 	dvbdev = dvb_minors[iminor(inode)];
79 
80 	if (dvbdev && dvbdev->fops) {
81 		int err = 0;
82 		const struct file_operations *new_fops;
83 
84 		new_fops = fops_get(dvbdev->fops);
85 		if (!new_fops)
86 			goto fail;
87 		file->private_data = dvbdev;
88 		replace_fops(file, new_fops);
89 		if (file->f_op->open)
90 			err = file->f_op->open(inode, file);
91 		up_read(&minor_rwsem);
92 		mutex_unlock(&dvbdev_mutex);
93 		return err;
94 	}
95 fail:
96 	up_read(&minor_rwsem);
97 	mutex_unlock(&dvbdev_mutex);
98 	return -ENODEV;
99 }
100 
101 
102 static const struct file_operations dvb_device_fops =
103 {
104 	.owner =	THIS_MODULE,
105 	.open =		dvb_device_open,
106 	.llseek =	noop_llseek,
107 };
108 
109 static struct cdev dvb_device_cdev;
110 
111 int dvb_generic_open(struct inode *inode, struct file *file)
112 {
113 	struct dvb_device *dvbdev = file->private_data;
114 
115 	if (!dvbdev)
116 		return -ENODEV;
117 
118 	if (!dvbdev->users)
119 		return -EBUSY;
120 
121 	if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
122 		if (!dvbdev->readers)
123 			return -EBUSY;
124 		dvbdev->readers--;
125 	} else {
126 		if (!dvbdev->writers)
127 			return -EBUSY;
128 		dvbdev->writers--;
129 	}
130 
131 	dvbdev->users--;
132 	return 0;
133 }
134 EXPORT_SYMBOL(dvb_generic_open);
135 
136 
137 int dvb_generic_release(struct inode *inode, struct file *file)
138 {
139 	struct dvb_device *dvbdev = file->private_data;
140 
141 	if (!dvbdev)
142 		return -ENODEV;
143 
144 	if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
145 		dvbdev->readers++;
146 	} else {
147 		dvbdev->writers++;
148 	}
149 
150 	dvbdev->users++;
151 	return 0;
152 }
153 EXPORT_SYMBOL(dvb_generic_release);
154 
155 
156 long dvb_generic_ioctl(struct file *file,
157 		       unsigned int cmd, unsigned long arg)
158 {
159 	struct dvb_device *dvbdev = file->private_data;
160 
161 	if (!dvbdev)
162 		return -ENODEV;
163 
164 	if (!dvbdev->kernel_ioctl)
165 		return -EINVAL;
166 
167 	return dvb_usercopy(file, cmd, arg, dvbdev->kernel_ioctl);
168 }
169 EXPORT_SYMBOL(dvb_generic_ioctl);
170 
171 
172 static int dvbdev_get_free_id (struct dvb_adapter *adap, int type)
173 {
174 	u32 id = 0;
175 
176 	while (id < DVB_MAX_IDS) {
177 		struct dvb_device *dev;
178 		list_for_each_entry(dev, &adap->device_list, list_head)
179 			if (dev->type == type && dev->id == id)
180 				goto skip;
181 		return id;
182 skip:
183 		id++;
184 	}
185 	return -ENFILE;
186 }
187 
188 static void dvb_media_device_free(struct dvb_device *dvbdev)
189 {
190 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
191 	if (dvbdev->entity) {
192 		media_device_unregister_entity(dvbdev->entity);
193 		kfree(dvbdev->entity);
194 		kfree(dvbdev->pads);
195 		dvbdev->entity = NULL;
196 		dvbdev->pads = NULL;
197 	}
198 
199 	if (dvbdev->tsout_entity) {
200 		int i;
201 
202 		for (i = 0; i < dvbdev->tsout_num_entities; i++) {
203 			media_device_unregister_entity(&dvbdev->tsout_entity[i]);
204 			kfree(dvbdev->tsout_entity[i].name);
205 		}
206 		kfree(dvbdev->tsout_entity);
207 		kfree(dvbdev->tsout_pads);
208 		dvbdev->tsout_entity = NULL;
209 		dvbdev->tsout_pads = NULL;
210 
211 		dvbdev->tsout_num_entities = 0;
212 	}
213 
214 	if (dvbdev->intf_devnode) {
215 		media_devnode_remove(dvbdev->intf_devnode);
216 		dvbdev->intf_devnode = NULL;
217 	}
218 
219 	if (dvbdev->adapter->conn) {
220 		media_device_unregister_entity(dvbdev->adapter->conn);
221 		dvbdev->adapter->conn = NULL;
222 		kfree(dvbdev->adapter->conn_pads);
223 		dvbdev->adapter->conn_pads = NULL;
224 	}
225 #endif
226 }
227 
228 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
229 static int dvb_create_tsout_entity(struct dvb_device *dvbdev,
230 				    const char *name, int npads)
231 {
232 	int i, ret = 0;
233 
234 	dvbdev->tsout_pads = kcalloc(npads, sizeof(*dvbdev->tsout_pads),
235 				     GFP_KERNEL);
236 	if (!dvbdev->tsout_pads)
237 		return -ENOMEM;
238 
239 	dvbdev->tsout_entity = kcalloc(npads, sizeof(*dvbdev->tsout_entity),
240 				       GFP_KERNEL);
241 	if (!dvbdev->tsout_entity)
242 		return -ENOMEM;
243 
244 	dvbdev->tsout_num_entities = npads;
245 
246 	for (i = 0; i < npads; i++) {
247 		struct media_pad *pads = &dvbdev->tsout_pads[i];
248 		struct media_entity *entity = &dvbdev->tsout_entity[i];
249 
250 		entity->name = kasprintf(GFP_KERNEL, "%s #%d", name, i);
251 		if (!entity->name)
252 			return -ENOMEM;
253 
254 		entity->function = MEDIA_ENT_F_IO_DTV;
255 		pads->flags = MEDIA_PAD_FL_SINK;
256 
257 		ret = media_entity_pads_init(entity, 1, pads);
258 		if (ret < 0)
259 			return ret;
260 
261 		ret = media_device_register_entity(dvbdev->adapter->mdev,
262 						   entity);
263 		if (ret < 0)
264 			return ret;
265 	}
266 	return 0;
267 }
268 
269 #define DEMUX_TSOUT	"demux-tsout"
270 #define DVR_TSOUT	"dvr-tsout"
271 
272 static int dvb_create_media_entity(struct dvb_device *dvbdev,
273 				   int type, int demux_sink_pads)
274 {
275 	int i, ret, npads;
276 
277 	switch (type) {
278 	case DVB_DEVICE_FRONTEND:
279 		npads = 2;
280 		break;
281 	case DVB_DEVICE_DVR:
282 		ret = dvb_create_tsout_entity(dvbdev, DVR_TSOUT,
283 					      demux_sink_pads);
284 		return ret;
285 	case DVB_DEVICE_DEMUX:
286 		npads = 1 + demux_sink_pads;
287 		ret = dvb_create_tsout_entity(dvbdev, DEMUX_TSOUT,
288 					      demux_sink_pads);
289 		if (ret < 0)
290 			return ret;
291 		break;
292 	case DVB_DEVICE_CA:
293 		npads = 2;
294 		break;
295 	case DVB_DEVICE_NET:
296 		/*
297 		 * We should be creating entities for the MPE/ULE
298 		 * decapsulation hardware (or software implementation).
299 		 *
300 		 * However, the number of for the MPE/ULE decaps may not be
301 		 * fixed. As we don't have yet dynamic support for PADs at
302 		 * the Media Controller, let's not create the decap
303 		 * entities yet.
304 		 */
305 		return 0;
306 	default:
307 		return 0;
308 	}
309 
310 	dvbdev->entity = kzalloc(sizeof(*dvbdev->entity), GFP_KERNEL);
311 	if (!dvbdev->entity)
312 		return -ENOMEM;
313 
314 	dvbdev->entity->name = dvbdev->name;
315 
316 	if (npads) {
317 		dvbdev->pads = kcalloc(npads, sizeof(*dvbdev->pads),
318 				       GFP_KERNEL);
319 		if (!dvbdev->pads)
320 			return -ENOMEM;
321 	}
322 
323 	switch (type) {
324 	case DVB_DEVICE_FRONTEND:
325 		dvbdev->entity->function = MEDIA_ENT_F_DTV_DEMOD;
326 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
327 		dvbdev->pads[1].flags = MEDIA_PAD_FL_SOURCE;
328 		break;
329 	case DVB_DEVICE_DEMUX:
330 		dvbdev->entity->function = MEDIA_ENT_F_TS_DEMUX;
331 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
332 		for (i = 1; i < npads; i++)
333 			dvbdev->pads[i].flags = MEDIA_PAD_FL_SOURCE;
334 		break;
335 	case DVB_DEVICE_CA:
336 		dvbdev->entity->function = MEDIA_ENT_F_DTV_CA;
337 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
338 		dvbdev->pads[1].flags = MEDIA_PAD_FL_SOURCE;
339 		break;
340 	default:
341 		/* Should never happen, as the first switch prevents it */
342 		kfree(dvbdev->entity);
343 		kfree(dvbdev->pads);
344 		dvbdev->entity = NULL;
345 		dvbdev->pads = NULL;
346 		return 0;
347 	}
348 
349 	if (npads) {
350 		ret = media_entity_pads_init(dvbdev->entity, npads, dvbdev->pads);
351 		if (ret)
352 			return ret;
353 	}
354 	ret = media_device_register_entity(dvbdev->adapter->mdev,
355 					   dvbdev->entity);
356 	if (ret)
357 		return ret;
358 
359 	pr_info("%s: media entity '%s' registered.\n",
360 		__func__, dvbdev->entity->name);
361 
362 	return 0;
363 }
364 #endif
365 
366 static int dvb_register_media_device(struct dvb_device *dvbdev,
367 				     int type, int minor,
368 				     unsigned demux_sink_pads)
369 {
370 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
371 	struct media_link *link;
372 	u32 intf_type;
373 	int ret;
374 
375 	if (!dvbdev->adapter->mdev)
376 		return 0;
377 
378 	ret = dvb_create_media_entity(dvbdev, type, demux_sink_pads);
379 	if (ret)
380 		return ret;
381 
382 	switch (type) {
383 	case DVB_DEVICE_FRONTEND:
384 		intf_type = MEDIA_INTF_T_DVB_FE;
385 		break;
386 	case DVB_DEVICE_DEMUX:
387 		intf_type = MEDIA_INTF_T_DVB_DEMUX;
388 		break;
389 	case DVB_DEVICE_DVR:
390 		intf_type = MEDIA_INTF_T_DVB_DVR;
391 		break;
392 	case DVB_DEVICE_CA:
393 		intf_type = MEDIA_INTF_T_DVB_CA;
394 		break;
395 	case DVB_DEVICE_NET:
396 		intf_type = MEDIA_INTF_T_DVB_NET;
397 		break;
398 	default:
399 		return 0;
400 	}
401 
402 	dvbdev->intf_devnode = media_devnode_create(dvbdev->adapter->mdev,
403 						    intf_type, 0,
404 						    DVB_MAJOR, minor);
405 
406 	if (!dvbdev->intf_devnode)
407 		return -ENOMEM;
408 
409 	/*
410 	 * Create the "obvious" link, e. g. the ones that represent
411 	 * a direct association between an interface and an entity.
412 	 * Other links should be created elsewhere, like:
413 	 *		DVB FE intf    -> tuner
414 	 *		DVB demux intf -> dvr
415 	 */
416 
417 	if (!dvbdev->entity)
418 		return 0;
419 
420 	link = media_create_intf_link(dvbdev->entity, &dvbdev->intf_devnode->intf,
421 				      MEDIA_LNK_FL_ENABLED);
422 	if (!link)
423 		return -ENOMEM;
424 #endif
425 	return 0;
426 }
427 
428 int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
429 			const struct dvb_device *template, void *priv, int type,
430 			int demux_sink_pads)
431 {
432 	struct dvb_device *dvbdev;
433 	struct file_operations *dvbdevfops;
434 	struct device *clsdev;
435 	int minor;
436 	int id, ret;
437 
438 	mutex_lock(&dvbdev_register_lock);
439 
440 	if ((id = dvbdev_get_free_id (adap, type)) < 0){
441 		mutex_unlock(&dvbdev_register_lock);
442 		*pdvbdev = NULL;
443 		pr_err("%s: couldn't find free device id\n", __func__);
444 		return -ENFILE;
445 	}
446 
447 	*pdvbdev = dvbdev = kzalloc(sizeof(*dvbdev), GFP_KERNEL);
448 
449 	if (!dvbdev){
450 		mutex_unlock(&dvbdev_register_lock);
451 		return -ENOMEM;
452 	}
453 
454 	dvbdevfops = kzalloc(sizeof(struct file_operations), GFP_KERNEL);
455 
456 	if (!dvbdevfops){
457 		kfree (dvbdev);
458 		mutex_unlock(&dvbdev_register_lock);
459 		return -ENOMEM;
460 	}
461 
462 	memcpy(dvbdev, template, sizeof(struct dvb_device));
463 	dvbdev->type = type;
464 	dvbdev->id = id;
465 	dvbdev->adapter = adap;
466 	dvbdev->priv = priv;
467 	dvbdev->fops = dvbdevfops;
468 	init_waitqueue_head (&dvbdev->wait_queue);
469 
470 	memcpy(dvbdevfops, template->fops, sizeof(struct file_operations));
471 	dvbdevfops->owner = adap->module;
472 
473 	list_add_tail (&dvbdev->list_head, &adap->device_list);
474 
475 	down_write(&minor_rwsem);
476 #ifdef CONFIG_DVB_DYNAMIC_MINORS
477 	for (minor = 0; minor < MAX_DVB_MINORS; minor++)
478 		if (dvb_minors[minor] == NULL)
479 			break;
480 
481 	if (minor == MAX_DVB_MINORS) {
482 		kfree(dvbdevfops);
483 		kfree(dvbdev);
484 		up_write(&minor_rwsem);
485 		mutex_unlock(&dvbdev_register_lock);
486 		return -EINVAL;
487 	}
488 #else
489 	minor = nums2minor(adap->num, type, id);
490 #endif
491 
492 	dvbdev->minor = minor;
493 	dvb_minors[minor] = dvbdev;
494 	up_write(&minor_rwsem);
495 
496 	ret = dvb_register_media_device(dvbdev, type, minor, demux_sink_pads);
497 	if (ret) {
498 		pr_err("%s: dvb_register_media_device failed to create the mediagraph\n",
499 		      __func__);
500 
501 		dvb_media_device_free(dvbdev);
502 		kfree(dvbdevfops);
503 		kfree(dvbdev);
504 		up_write(&minor_rwsem);
505 		mutex_unlock(&dvbdev_register_lock);
506 		return ret;
507 	}
508 
509 	mutex_unlock(&dvbdev_register_lock);
510 
511 	clsdev = device_create(dvb_class, adap->device,
512 			       MKDEV(DVB_MAJOR, minor),
513 			       dvbdev, "dvb%d.%s%d", adap->num, dnames[type], id);
514 	if (IS_ERR(clsdev)) {
515 		pr_err("%s: failed to create device dvb%d.%s%d (%ld)\n",
516 		       __func__, adap->num, dnames[type], id, PTR_ERR(clsdev));
517 		return PTR_ERR(clsdev);
518 	}
519 	dprintk("DVB: register adapter%d/%s%d @ minor: %i (0x%02x)\n",
520 		adap->num, dnames[type], id, minor, minor);
521 
522 	return 0;
523 }
524 EXPORT_SYMBOL(dvb_register_device);
525 
526 
527 void dvb_remove_device(struct dvb_device *dvbdev)
528 {
529 	if (!dvbdev)
530 		return;
531 
532 	down_write(&minor_rwsem);
533 	dvb_minors[dvbdev->minor] = NULL;
534 	up_write(&minor_rwsem);
535 
536 	dvb_media_device_free(dvbdev);
537 
538 	device_destroy(dvb_class, MKDEV(DVB_MAJOR, dvbdev->minor));
539 
540 	list_del (&dvbdev->list_head);
541 }
542 EXPORT_SYMBOL(dvb_remove_device);
543 
544 
545 void dvb_free_device(struct dvb_device *dvbdev)
546 {
547 	if (!dvbdev)
548 		return;
549 
550 	kfree (dvbdev->fops);
551 	kfree (dvbdev);
552 }
553 EXPORT_SYMBOL(dvb_free_device);
554 
555 
556 void dvb_unregister_device(struct dvb_device *dvbdev)
557 {
558 	dvb_remove_device(dvbdev);
559 	dvb_free_device(dvbdev);
560 }
561 EXPORT_SYMBOL(dvb_unregister_device);
562 
563 
564 #ifdef CONFIG_MEDIA_CONTROLLER_DVB
565 
566 static int dvb_create_io_intf_links(struct dvb_adapter *adap,
567 				    struct media_interface *intf,
568 				    char *name)
569 {
570 	struct media_device *mdev = adap->mdev;
571 	struct media_entity *entity;
572 	struct media_link *link;
573 
574 	media_device_for_each_entity(entity, mdev) {
575 		if (entity->function == MEDIA_ENT_F_IO_DTV) {
576 			if (strncmp(entity->name, name, strlen(name)))
577 				continue;
578 			link = media_create_intf_link(entity, intf,
579 						      MEDIA_LNK_FL_ENABLED);
580 			if (!link)
581 				return -ENOMEM;
582 		}
583 	}
584 	return 0;
585 }
586 
587 int dvb_create_media_graph(struct dvb_adapter *adap,
588 			   bool create_rf_connector)
589 {
590 	struct media_device *mdev = adap->mdev;
591 	struct media_entity *entity, *tuner = NULL, *demod = NULL, *conn;
592 	struct media_entity *demux = NULL, *ca = NULL;
593 	struct media_link *link;
594 	struct media_interface *intf;
595 	unsigned demux_pad = 0;
596 	unsigned dvr_pad = 0;
597 	unsigned ntuner = 0, ndemod = 0;
598 	int ret;
599 	static const char *connector_name = "Television";
600 
601 	if (!mdev)
602 		return 0;
603 
604 	media_device_for_each_entity(entity, mdev) {
605 		switch (entity->function) {
606 		case MEDIA_ENT_F_TUNER:
607 			tuner = entity;
608 			ntuner++;
609 			break;
610 		case MEDIA_ENT_F_DTV_DEMOD:
611 			demod = entity;
612 			ndemod++;
613 			break;
614 		case MEDIA_ENT_F_TS_DEMUX:
615 			demux = entity;
616 			break;
617 		case MEDIA_ENT_F_DTV_CA:
618 			ca = entity;
619 			break;
620 		}
621 	}
622 
623 	/*
624 	 * Prepare to signalize to media_create_pad_links() that multiple
625 	 * entities of the same type exists and a 1:n or n:1 links need to be
626 	 * created.
627 	 * NOTE: if both tuner and demod have multiple instances, it is up
628 	 * to the caller driver to create such links.
629 	 */
630 	if (ntuner > 1)
631 		tuner = NULL;
632 	if (ndemod > 1)
633 		demod = NULL;
634 
635 	if (create_rf_connector) {
636 		conn = kzalloc(sizeof(*conn), GFP_KERNEL);
637 		if (!conn)
638 			return -ENOMEM;
639 		adap->conn = conn;
640 
641 		adap->conn_pads = kzalloc(sizeof(*adap->conn_pads), GFP_KERNEL);
642 		if (!adap->conn_pads)
643 			return -ENOMEM;
644 
645 		conn->flags = MEDIA_ENT_FL_CONNECTOR;
646 		conn->function = MEDIA_ENT_F_CONN_RF;
647 		conn->name = connector_name;
648 		adap->conn_pads->flags = MEDIA_PAD_FL_SOURCE;
649 
650 		ret = media_entity_pads_init(conn, 1, adap->conn_pads);
651 		if (ret)
652 			return ret;
653 
654 		ret = media_device_register_entity(mdev, conn);
655 		if (ret)
656 			return ret;
657 
658 		if (!ntuner)
659 			ret = media_create_pad_links(mdev,
660 						     MEDIA_ENT_F_CONN_RF,
661 						     conn, 0,
662 						     MEDIA_ENT_F_DTV_DEMOD,
663 						     demod, 0,
664 						     MEDIA_LNK_FL_ENABLED,
665 						     false);
666 		else
667 			ret = media_create_pad_links(mdev,
668 						     MEDIA_ENT_F_CONN_RF,
669 						     conn, 0,
670 						     MEDIA_ENT_F_TUNER,
671 						     tuner, TUNER_PAD_RF_INPUT,
672 						     MEDIA_LNK_FL_ENABLED,
673 						     false);
674 		if (ret)
675 			return ret;
676 	}
677 
678 	if (ntuner && ndemod) {
679 		ret = media_create_pad_links(mdev,
680 					     MEDIA_ENT_F_TUNER,
681 					     tuner, TUNER_PAD_OUTPUT,
682 					     MEDIA_ENT_F_DTV_DEMOD,
683 					     demod, 0, MEDIA_LNK_FL_ENABLED,
684 					     false);
685 		if (ret)
686 			return ret;
687 	}
688 
689 	if (ndemod && demux) {
690 		ret = media_create_pad_links(mdev,
691 					     MEDIA_ENT_F_DTV_DEMOD,
692 					     demod, 1,
693 					     MEDIA_ENT_F_TS_DEMUX,
694 					     demux, 0, MEDIA_LNK_FL_ENABLED,
695 					     false);
696 		if (ret)
697 			return ret;
698 	}
699 	if (demux && ca) {
700 		ret = media_create_pad_link(demux, 1, ca,
701 					    0, MEDIA_LNK_FL_ENABLED);
702 		if (ret)
703 			return ret;
704 	}
705 
706 	/* Create demux links for each ringbuffer/pad */
707 	if (demux) {
708 		media_device_for_each_entity(entity, mdev) {
709 			if (entity->function == MEDIA_ENT_F_IO_DTV) {
710 				if (!strncmp(entity->name, DVR_TSOUT,
711 				    strlen(DVR_TSOUT))) {
712 					ret = media_create_pad_link(demux,
713 								++dvr_pad,
714 							    entity, 0, 0);
715 					if (ret)
716 						return ret;
717 				}
718 				if (!strncmp(entity->name, DEMUX_TSOUT,
719 				    strlen(DEMUX_TSOUT))) {
720 					ret = media_create_pad_link(demux,
721 							      ++demux_pad,
722 							    entity, 0, 0);
723 					if (ret)
724 						return ret;
725 				}
726 			}
727 		}
728 	}
729 
730 	/* Create interface links for FE->tuner, DVR->demux and CA->ca */
731 	media_device_for_each_intf(intf, mdev) {
732 		if (intf->type == MEDIA_INTF_T_DVB_CA && ca) {
733 			link = media_create_intf_link(ca, intf,
734 						      MEDIA_LNK_FL_ENABLED);
735 			if (!link)
736 				return -ENOMEM;
737 		}
738 
739 		if (intf->type == MEDIA_INTF_T_DVB_FE && tuner) {
740 			link = media_create_intf_link(tuner, intf,
741 						      MEDIA_LNK_FL_ENABLED);
742 			if (!link)
743 				return -ENOMEM;
744 		}
745 #if 0
746 		/*
747 		 * Indirect link - let's not create yet, as we don't know how
748 		 *		   to handle indirect links, nor if this will
749 		 *		   actually be needed.
750 		 */
751 		if (intf->type == MEDIA_INTF_T_DVB_DVR && demux) {
752 			link = media_create_intf_link(demux, intf,
753 						      MEDIA_LNK_FL_ENABLED);
754 			if (!link)
755 				return -ENOMEM;
756 		}
757 #endif
758 		if (intf->type == MEDIA_INTF_T_DVB_DVR) {
759 			ret = dvb_create_io_intf_links(adap, intf, DVR_TSOUT);
760 			if (ret)
761 				return ret;
762 		}
763 		if (intf->type == MEDIA_INTF_T_DVB_DEMUX) {
764 			ret = dvb_create_io_intf_links(adap, intf, DEMUX_TSOUT);
765 			if (ret)
766 				return ret;
767 		}
768 	}
769 	return 0;
770 }
771 EXPORT_SYMBOL_GPL(dvb_create_media_graph);
772 #endif
773 
774 static int dvbdev_check_free_adapter_num(int num)
775 {
776 	struct list_head *entry;
777 	list_for_each(entry, &dvb_adapter_list) {
778 		struct dvb_adapter *adap;
779 		adap = list_entry(entry, struct dvb_adapter, list_head);
780 		if (adap->num == num)
781 			return 0;
782 	}
783 	return 1;
784 }
785 
786 static int dvbdev_get_free_adapter_num (void)
787 {
788 	int num = 0;
789 
790 	while (num < DVB_MAX_ADAPTERS) {
791 		if (dvbdev_check_free_adapter_num(num))
792 			return num;
793 		num++;
794 	}
795 
796 	return -ENFILE;
797 }
798 
799 
800 int dvb_register_adapter(struct dvb_adapter *adap, const char *name,
801 			 struct module *module, struct device *device,
802 			 short *adapter_nums)
803 {
804 	int i, num;
805 
806 	mutex_lock(&dvbdev_register_lock);
807 
808 	for (i = 0; i < DVB_MAX_ADAPTERS; ++i) {
809 		num = adapter_nums[i];
810 		if (num >= 0  &&  num < DVB_MAX_ADAPTERS) {
811 		/* use the one the driver asked for */
812 			if (dvbdev_check_free_adapter_num(num))
813 				break;
814 		} else {
815 			num = dvbdev_get_free_adapter_num();
816 			break;
817 		}
818 		num = -1;
819 	}
820 
821 	if (num < 0) {
822 		mutex_unlock(&dvbdev_register_lock);
823 		return -ENFILE;
824 	}
825 
826 	memset (adap, 0, sizeof(struct dvb_adapter));
827 	INIT_LIST_HEAD (&adap->device_list);
828 
829 	pr_info("DVB: registering new adapter (%s)\n", name);
830 
831 	adap->num = num;
832 	adap->name = name;
833 	adap->module = module;
834 	adap->device = device;
835 	adap->mfe_shared = 0;
836 	adap->mfe_dvbdev = NULL;
837 	mutex_init (&adap->mfe_lock);
838 
839 	list_add_tail (&adap->list_head, &dvb_adapter_list);
840 
841 	mutex_unlock(&dvbdev_register_lock);
842 
843 	return num;
844 }
845 EXPORT_SYMBOL(dvb_register_adapter);
846 
847 
848 int dvb_unregister_adapter(struct dvb_adapter *adap)
849 {
850 	mutex_lock(&dvbdev_register_lock);
851 	list_del (&adap->list_head);
852 	mutex_unlock(&dvbdev_register_lock);
853 	return 0;
854 }
855 EXPORT_SYMBOL(dvb_unregister_adapter);
856 
857 /* if the miracle happens and "generic_usercopy()" is included into
858    the kernel, then this can vanish. please don't make the mistake and
859    define this as video_usercopy(). this will introduce a dependecy
860    to the v4l "videodev.o" module, which is unnecessary for some
861    cards (ie. the budget dvb-cards don't need the v4l module...) */
862 int dvb_usercopy(struct file *file,
863 		     unsigned int cmd, unsigned long arg,
864 		     int (*func)(struct file *file,
865 		     unsigned int cmd, void *arg))
866 {
867 	char    sbuf[128];
868 	void    *mbuf = NULL;
869 	void    *parg = NULL;
870 	int     err  = -EINVAL;
871 
872 	/*  Copy arguments into temp kernel buffer  */
873 	switch (_IOC_DIR(cmd)) {
874 	case _IOC_NONE:
875 		/*
876 		 * For this command, the pointer is actually an integer
877 		 * argument.
878 		 */
879 		parg = (void *) arg;
880 		break;
881 	case _IOC_READ: /* some v4l ioctls are marked wrong ... */
882 	case _IOC_WRITE:
883 	case (_IOC_WRITE | _IOC_READ):
884 		if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
885 			parg = sbuf;
886 		} else {
887 			/* too big to allocate from stack */
888 			mbuf = kmalloc(_IOC_SIZE(cmd), GFP_KERNEL);
889 			if (NULL == mbuf)
890 				return -ENOMEM;
891 			parg = mbuf;
892 		}
893 
894 		err = -EFAULT;
895 		if (copy_from_user(parg, (void __user *)arg, _IOC_SIZE(cmd)))
896 			goto out;
897 		break;
898 	}
899 
900 	/* call driver */
901 	if ((err = func(file, cmd, parg)) == -ENOIOCTLCMD)
902 		err = -ENOTTY;
903 
904 	if (err < 0)
905 		goto out;
906 
907 	/*  Copy results into user buffer  */
908 	switch (_IOC_DIR(cmd))
909 	{
910 	case _IOC_READ:
911 	case (_IOC_WRITE | _IOC_READ):
912 		if (copy_to_user((void __user *)arg, parg, _IOC_SIZE(cmd)))
913 			err = -EFAULT;
914 		break;
915 	}
916 
917 out:
918 	kfree(mbuf);
919 	return err;
920 }
921 
922 static int dvb_uevent(struct device *dev, struct kobj_uevent_env *env)
923 {
924 	struct dvb_device *dvbdev = dev_get_drvdata(dev);
925 
926 	add_uevent_var(env, "DVB_ADAPTER_NUM=%d", dvbdev->adapter->num);
927 	add_uevent_var(env, "DVB_DEVICE_TYPE=%s", dnames[dvbdev->type]);
928 	add_uevent_var(env, "DVB_DEVICE_NUM=%d", dvbdev->id);
929 	return 0;
930 }
931 
932 static char *dvb_devnode(struct device *dev, umode_t *mode)
933 {
934 	struct dvb_device *dvbdev = dev_get_drvdata(dev);
935 
936 	return kasprintf(GFP_KERNEL, "dvb/adapter%d/%s%d",
937 		dvbdev->adapter->num, dnames[dvbdev->type], dvbdev->id);
938 }
939 
940 
941 static int __init init_dvbdev(void)
942 {
943 	int retval;
944 	dev_t dev = MKDEV(DVB_MAJOR, 0);
945 
946 	if ((retval = register_chrdev_region(dev, MAX_DVB_MINORS, "DVB")) != 0) {
947 		pr_err("dvb-core: unable to get major %d\n", DVB_MAJOR);
948 		return retval;
949 	}
950 
951 	cdev_init(&dvb_device_cdev, &dvb_device_fops);
952 	if ((retval = cdev_add(&dvb_device_cdev, dev, MAX_DVB_MINORS)) != 0) {
953 		pr_err("dvb-core: unable register character device\n");
954 		goto error;
955 	}
956 
957 	dvb_class = class_create(THIS_MODULE, "dvb");
958 	if (IS_ERR(dvb_class)) {
959 		retval = PTR_ERR(dvb_class);
960 		goto error;
961 	}
962 	dvb_class->dev_uevent = dvb_uevent;
963 	dvb_class->devnode = dvb_devnode;
964 	return 0;
965 
966 error:
967 	cdev_del(&dvb_device_cdev);
968 	unregister_chrdev_region(dev, MAX_DVB_MINORS);
969 	return retval;
970 }
971 
972 
973 static void __exit exit_dvbdev(void)
974 {
975 	class_destroy(dvb_class);
976 	cdev_del(&dvb_device_cdev);
977 	unregister_chrdev_region(MKDEV(DVB_MAJOR, 0), MAX_DVB_MINORS);
978 }
979 
980 subsys_initcall(init_dvbdev);
981 module_exit(exit_dvbdev);
982 
983 MODULE_DESCRIPTION("DVB Core Driver");
984 MODULE_AUTHOR("Marcus Metzler, Ralph Metzler, Holger Waechtler");
985 MODULE_LICENSE("GPL");
986