xref: /openbmc/linux/drivers/media/dvb-core/dvbdev.c (revision a531b0c2)
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/i2c.h>
28 #include <linux/init.h>
29 #include <linux/slab.h>
30 #include <linux/device.h>
31 #include <linux/fs.h>
32 #include <linux/cdev.h>
33 #include <linux/mutex.h>
34 #include <media/dvbdev.h>
35 
36 /* Due to enum tuner_pad_index */
37 #include <media/tuner.h>
38 
39 static DEFINE_MUTEX(dvbdev_mutex);
40 static int dvbdev_debug;
41 
42 module_param(dvbdev_debug, int, 0644);
43 MODULE_PARM_DESC(dvbdev_debug, "Turn on/off device debugging (default:off).");
44 
45 #define dprintk(fmt, arg...) do {					\
46 	if (dvbdev_debug)						\
47 		printk(KERN_DEBUG pr_fmt("%s: " fmt),			\
48 		       __func__, ##arg);				\
49 } while (0)
50 
51 static LIST_HEAD(dvb_adapter_list);
52 static DEFINE_MUTEX(dvbdev_register_lock);
53 
54 static const char * const dnames[] = {
55 	[DVB_DEVICE_VIDEO] =		"video",
56 	[DVB_DEVICE_AUDIO] =		"audio",
57 	[DVB_DEVICE_SEC] =		"sec",
58 	[DVB_DEVICE_FRONTEND] =		"frontend",
59 	[DVB_DEVICE_DEMUX] =		"demux",
60 	[DVB_DEVICE_DVR] =		"dvr",
61 	[DVB_DEVICE_CA] =		"ca",
62 	[DVB_DEVICE_NET] =		"net",
63 	[DVB_DEVICE_OSD] =		"osd"
64 };
65 
66 #ifdef CONFIG_DVB_DYNAMIC_MINORS
67 #define MAX_DVB_MINORS		256
68 #define DVB_MAX_IDS		MAX_DVB_MINORS
69 #else
70 #define DVB_MAX_IDS		4
71 
72 static const u8 minor_type[] = {
73        [DVB_DEVICE_VIDEO]      = 0,
74        [DVB_DEVICE_AUDIO]      = 1,
75        [DVB_DEVICE_SEC]        = 2,
76        [DVB_DEVICE_FRONTEND]   = 3,
77        [DVB_DEVICE_DEMUX]      = 4,
78        [DVB_DEVICE_DVR]        = 5,
79        [DVB_DEVICE_CA]         = 6,
80        [DVB_DEVICE_NET]        = 7,
81        [DVB_DEVICE_OSD]        = 8,
82 };
83 
84 #define nums2minor(num, type, id) \
85        (((num) << 6) | ((id) << 4) | minor_type[type])
86 
87 #define MAX_DVB_MINORS		(DVB_MAX_ADAPTERS*64)
88 #endif
89 
90 static struct class *dvb_class;
91 
92 static struct dvb_device *dvb_minors[MAX_DVB_MINORS];
93 static DECLARE_RWSEM(minor_rwsem);
94 
95 static int dvb_device_open(struct inode *inode, struct file *file)
96 {
97 	struct dvb_device *dvbdev;
98 
99 	mutex_lock(&dvbdev_mutex);
100 	down_read(&minor_rwsem);
101 	dvbdev = dvb_minors[iminor(inode)];
102 
103 	if (dvbdev && dvbdev->fops) {
104 		int err = 0;
105 		const struct file_operations *new_fops;
106 
107 		new_fops = fops_get(dvbdev->fops);
108 		if (!new_fops)
109 			goto fail;
110 		file->private_data = dvbdev;
111 		replace_fops(file, new_fops);
112 		if (file->f_op->open)
113 			err = file->f_op->open(inode, file);
114 		up_read(&minor_rwsem);
115 		mutex_unlock(&dvbdev_mutex);
116 		return err;
117 	}
118 fail:
119 	up_read(&minor_rwsem);
120 	mutex_unlock(&dvbdev_mutex);
121 	return -ENODEV;
122 }
123 
124 
125 static const struct file_operations dvb_device_fops =
126 {
127 	.owner =	THIS_MODULE,
128 	.open =		dvb_device_open,
129 	.llseek =	noop_llseek,
130 };
131 
132 static struct cdev dvb_device_cdev;
133 
134 int dvb_generic_open(struct inode *inode, struct file *file)
135 {
136 	struct dvb_device *dvbdev = file->private_data;
137 
138 	if (!dvbdev)
139 		return -ENODEV;
140 
141 	if (!dvbdev->users)
142 		return -EBUSY;
143 
144 	if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
145 		if (!dvbdev->readers)
146 			return -EBUSY;
147 		dvbdev->readers--;
148 	} else {
149 		if (!dvbdev->writers)
150 			return -EBUSY;
151 		dvbdev->writers--;
152 	}
153 
154 	dvbdev->users--;
155 	return 0;
156 }
157 EXPORT_SYMBOL(dvb_generic_open);
158 
159 
160 int dvb_generic_release(struct inode *inode, struct file *file)
161 {
162 	struct dvb_device *dvbdev = file->private_data;
163 
164 	if (!dvbdev)
165 		return -ENODEV;
166 
167 	if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
168 		dvbdev->readers++;
169 	} else {
170 		dvbdev->writers++;
171 	}
172 
173 	dvbdev->users++;
174 	return 0;
175 }
176 EXPORT_SYMBOL(dvb_generic_release);
177 
178 
179 long dvb_generic_ioctl(struct file *file,
180 		       unsigned int cmd, unsigned long arg)
181 {
182 	struct dvb_device *dvbdev = file->private_data;
183 
184 	if (!dvbdev)
185 		return -ENODEV;
186 
187 	if (!dvbdev->kernel_ioctl)
188 		return -EINVAL;
189 
190 	return dvb_usercopy(file, cmd, arg, dvbdev->kernel_ioctl);
191 }
192 EXPORT_SYMBOL(dvb_generic_ioctl);
193 
194 
195 static int dvbdev_get_free_id (struct dvb_adapter *adap, int type)
196 {
197 	u32 id = 0;
198 
199 	while (id < DVB_MAX_IDS) {
200 		struct dvb_device *dev;
201 		list_for_each_entry(dev, &adap->device_list, list_head)
202 			if (dev->type == type && dev->id == id)
203 				goto skip;
204 		return id;
205 skip:
206 		id++;
207 	}
208 	return -ENFILE;
209 }
210 
211 static void dvb_media_device_free(struct dvb_device *dvbdev)
212 {
213 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
214 	if (dvbdev->entity) {
215 		media_device_unregister_entity(dvbdev->entity);
216 		kfree(dvbdev->entity);
217 		kfree(dvbdev->pads);
218 		dvbdev->entity = NULL;
219 		dvbdev->pads = NULL;
220 	}
221 
222 	if (dvbdev->tsout_entity) {
223 		int i;
224 
225 		for (i = 0; i < dvbdev->tsout_num_entities; i++) {
226 			media_device_unregister_entity(&dvbdev->tsout_entity[i]);
227 			kfree(dvbdev->tsout_entity[i].name);
228 		}
229 		kfree(dvbdev->tsout_entity);
230 		kfree(dvbdev->tsout_pads);
231 		dvbdev->tsout_entity = NULL;
232 		dvbdev->tsout_pads = NULL;
233 
234 		dvbdev->tsout_num_entities = 0;
235 	}
236 
237 	if (dvbdev->intf_devnode) {
238 		media_devnode_remove(dvbdev->intf_devnode);
239 		dvbdev->intf_devnode = NULL;
240 	}
241 
242 	if (dvbdev->adapter->conn) {
243 		media_device_unregister_entity(dvbdev->adapter->conn);
244 		kfree(dvbdev->adapter->conn);
245 		dvbdev->adapter->conn = NULL;
246 		kfree(dvbdev->adapter->conn_pads);
247 		dvbdev->adapter->conn_pads = NULL;
248 	}
249 #endif
250 }
251 
252 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
253 static int dvb_create_tsout_entity(struct dvb_device *dvbdev,
254 				    const char *name, int npads)
255 {
256 	int i, ret = 0;
257 
258 	dvbdev->tsout_pads = kcalloc(npads, sizeof(*dvbdev->tsout_pads),
259 				     GFP_KERNEL);
260 	if (!dvbdev->tsout_pads)
261 		return -ENOMEM;
262 
263 	dvbdev->tsout_entity = kcalloc(npads, sizeof(*dvbdev->tsout_entity),
264 				       GFP_KERNEL);
265 	if (!dvbdev->tsout_entity)
266 		return -ENOMEM;
267 
268 	dvbdev->tsout_num_entities = npads;
269 
270 	for (i = 0; i < npads; i++) {
271 		struct media_pad *pads = &dvbdev->tsout_pads[i];
272 		struct media_entity *entity = &dvbdev->tsout_entity[i];
273 
274 		entity->name = kasprintf(GFP_KERNEL, "%s #%d", name, i);
275 		if (!entity->name)
276 			return -ENOMEM;
277 
278 		entity->function = MEDIA_ENT_F_IO_DTV;
279 		pads->flags = MEDIA_PAD_FL_SINK;
280 
281 		ret = media_entity_pads_init(entity, 1, pads);
282 		if (ret < 0)
283 			return ret;
284 
285 		ret = media_device_register_entity(dvbdev->adapter->mdev,
286 						   entity);
287 		if (ret < 0)
288 			return ret;
289 	}
290 	return 0;
291 }
292 
293 #define DEMUX_TSOUT	"demux-tsout"
294 #define DVR_TSOUT	"dvr-tsout"
295 
296 static int dvb_create_media_entity(struct dvb_device *dvbdev,
297 				   int type, int demux_sink_pads)
298 {
299 	int i, ret, npads;
300 
301 	switch (type) {
302 	case DVB_DEVICE_FRONTEND:
303 		npads = 2;
304 		break;
305 	case DVB_DEVICE_DVR:
306 		ret = dvb_create_tsout_entity(dvbdev, DVR_TSOUT,
307 					      demux_sink_pads);
308 		return ret;
309 	case DVB_DEVICE_DEMUX:
310 		npads = 1 + demux_sink_pads;
311 		ret = dvb_create_tsout_entity(dvbdev, DEMUX_TSOUT,
312 					      demux_sink_pads);
313 		if (ret < 0)
314 			return ret;
315 		break;
316 	case DVB_DEVICE_CA:
317 		npads = 2;
318 		break;
319 	case DVB_DEVICE_NET:
320 		/*
321 		 * We should be creating entities for the MPE/ULE
322 		 * decapsulation hardware (or software implementation).
323 		 *
324 		 * However, the number of for the MPE/ULE decaps may not be
325 		 * fixed. As we don't have yet dynamic support for PADs at
326 		 * the Media Controller, let's not create the decap
327 		 * entities yet.
328 		 */
329 		return 0;
330 	default:
331 		return 0;
332 	}
333 
334 	dvbdev->entity = kzalloc(sizeof(*dvbdev->entity), GFP_KERNEL);
335 	if (!dvbdev->entity)
336 		return -ENOMEM;
337 
338 	dvbdev->entity->name = dvbdev->name;
339 
340 	if (npads) {
341 		dvbdev->pads = kcalloc(npads, sizeof(*dvbdev->pads),
342 				       GFP_KERNEL);
343 		if (!dvbdev->pads) {
344 			kfree(dvbdev->entity);
345 			return -ENOMEM;
346 		}
347 	}
348 
349 	switch (type) {
350 	case DVB_DEVICE_FRONTEND:
351 		dvbdev->entity->function = MEDIA_ENT_F_DTV_DEMOD;
352 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
353 		dvbdev->pads[1].flags = MEDIA_PAD_FL_SOURCE;
354 		break;
355 	case DVB_DEVICE_DEMUX:
356 		dvbdev->entity->function = MEDIA_ENT_F_TS_DEMUX;
357 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
358 		for (i = 1; i < npads; i++)
359 			dvbdev->pads[i].flags = MEDIA_PAD_FL_SOURCE;
360 		break;
361 	case DVB_DEVICE_CA:
362 		dvbdev->entity->function = MEDIA_ENT_F_DTV_CA;
363 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
364 		dvbdev->pads[1].flags = MEDIA_PAD_FL_SOURCE;
365 		break;
366 	default:
367 		/* Should never happen, as the first switch prevents it */
368 		kfree(dvbdev->entity);
369 		kfree(dvbdev->pads);
370 		dvbdev->entity = NULL;
371 		dvbdev->pads = NULL;
372 		return 0;
373 	}
374 
375 	if (npads) {
376 		ret = media_entity_pads_init(dvbdev->entity, npads, dvbdev->pads);
377 		if (ret)
378 			return ret;
379 	}
380 	ret = media_device_register_entity(dvbdev->adapter->mdev,
381 					   dvbdev->entity);
382 	if (ret)
383 		return ret;
384 
385 	pr_info("%s: media entity '%s' registered.\n",
386 		__func__, dvbdev->entity->name);
387 
388 	return 0;
389 }
390 #endif
391 
392 static int dvb_register_media_device(struct dvb_device *dvbdev,
393 				     int type, int minor,
394 				     unsigned demux_sink_pads)
395 {
396 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
397 	struct media_link *link;
398 	u32 intf_type;
399 	int ret;
400 
401 	if (!dvbdev->adapter->mdev)
402 		return 0;
403 
404 	ret = dvb_create_media_entity(dvbdev, type, demux_sink_pads);
405 	if (ret)
406 		return ret;
407 
408 	switch (type) {
409 	case DVB_DEVICE_FRONTEND:
410 		intf_type = MEDIA_INTF_T_DVB_FE;
411 		break;
412 	case DVB_DEVICE_DEMUX:
413 		intf_type = MEDIA_INTF_T_DVB_DEMUX;
414 		break;
415 	case DVB_DEVICE_DVR:
416 		intf_type = MEDIA_INTF_T_DVB_DVR;
417 		break;
418 	case DVB_DEVICE_CA:
419 		intf_type = MEDIA_INTF_T_DVB_CA;
420 		break;
421 	case DVB_DEVICE_NET:
422 		intf_type = MEDIA_INTF_T_DVB_NET;
423 		break;
424 	default:
425 		return 0;
426 	}
427 
428 	dvbdev->intf_devnode = media_devnode_create(dvbdev->adapter->mdev,
429 						    intf_type, 0,
430 						    DVB_MAJOR, minor);
431 
432 	if (!dvbdev->intf_devnode)
433 		return -ENOMEM;
434 
435 	/*
436 	 * Create the "obvious" link, e. g. the ones that represent
437 	 * a direct association between an interface and an entity.
438 	 * Other links should be created elsewhere, like:
439 	 *		DVB FE intf    -> tuner
440 	 *		DVB demux intf -> dvr
441 	 */
442 
443 	if (!dvbdev->entity)
444 		return 0;
445 
446 	link = media_create_intf_link(dvbdev->entity,
447 				      &dvbdev->intf_devnode->intf,
448 				      MEDIA_LNK_FL_ENABLED |
449 				      MEDIA_LNK_FL_IMMUTABLE);
450 	if (!link)
451 		return -ENOMEM;
452 #endif
453 	return 0;
454 }
455 
456 int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
457 			const struct dvb_device *template, void *priv,
458 			enum dvb_device_type type, int demux_sink_pads)
459 {
460 	struct dvb_device *dvbdev;
461 	struct file_operations *dvbdevfops;
462 	struct device *clsdev;
463 	int minor;
464 	int id, ret;
465 
466 	mutex_lock(&dvbdev_register_lock);
467 
468 	if ((id = dvbdev_get_free_id (adap, type)) < 0){
469 		mutex_unlock(&dvbdev_register_lock);
470 		*pdvbdev = NULL;
471 		pr_err("%s: couldn't find free device id\n", __func__);
472 		return -ENFILE;
473 	}
474 
475 	*pdvbdev = dvbdev = kzalloc(sizeof(*dvbdev), GFP_KERNEL);
476 
477 	if (!dvbdev){
478 		mutex_unlock(&dvbdev_register_lock);
479 		return -ENOMEM;
480 	}
481 
482 	dvbdevfops = kmemdup(template->fops, sizeof(*dvbdevfops), GFP_KERNEL);
483 
484 	if (!dvbdevfops){
485 		kfree (dvbdev);
486 		mutex_unlock(&dvbdev_register_lock);
487 		return -ENOMEM;
488 	}
489 
490 	memcpy(dvbdev, template, sizeof(struct dvb_device));
491 	dvbdev->type = type;
492 	dvbdev->id = id;
493 	dvbdev->adapter = adap;
494 	dvbdev->priv = priv;
495 	dvbdev->fops = dvbdevfops;
496 	init_waitqueue_head (&dvbdev->wait_queue);
497 
498 	dvbdevfops->owner = adap->module;
499 
500 	list_add_tail (&dvbdev->list_head, &adap->device_list);
501 
502 	down_write(&minor_rwsem);
503 #ifdef CONFIG_DVB_DYNAMIC_MINORS
504 	for (minor = 0; minor < MAX_DVB_MINORS; minor++)
505 		if (dvb_minors[minor] == NULL)
506 			break;
507 
508 	if (minor == MAX_DVB_MINORS) {
509 		list_del (&dvbdev->list_head);
510 		kfree(dvbdevfops);
511 		kfree(dvbdev);
512 		up_write(&minor_rwsem);
513 		mutex_unlock(&dvbdev_register_lock);
514 		return -EINVAL;
515 	}
516 #else
517 	minor = nums2minor(adap->num, type, id);
518 #endif
519 
520 	dvbdev->minor = minor;
521 	dvb_minors[minor] = dvbdev;
522 	up_write(&minor_rwsem);
523 
524 	ret = dvb_register_media_device(dvbdev, type, minor, demux_sink_pads);
525 	if (ret) {
526 		pr_err("%s: dvb_register_media_device failed to create the mediagraph\n",
527 		      __func__);
528 
529 		dvb_media_device_free(dvbdev);
530 		list_del (&dvbdev->list_head);
531 		kfree(dvbdevfops);
532 		kfree(dvbdev);
533 		mutex_unlock(&dvbdev_register_lock);
534 		return ret;
535 	}
536 
537 	mutex_unlock(&dvbdev_register_lock);
538 
539 	clsdev = device_create(dvb_class, adap->device,
540 			       MKDEV(DVB_MAJOR, minor),
541 			       dvbdev, "dvb%d.%s%d", adap->num, dnames[type], id);
542 	if (IS_ERR(clsdev)) {
543 		pr_err("%s: failed to create device dvb%d.%s%d (%ld)\n",
544 		       __func__, adap->num, dnames[type], id, PTR_ERR(clsdev));
545 		dvb_media_device_free(dvbdev);
546 		list_del (&dvbdev->list_head);
547 		kfree(dvbdevfops);
548 		kfree(dvbdev);
549 		return PTR_ERR(clsdev);
550 	}
551 	dprintk("DVB: register adapter%d/%s%d @ minor: %i (0x%02x)\n",
552 		adap->num, dnames[type], id, minor, minor);
553 
554 	return 0;
555 }
556 EXPORT_SYMBOL(dvb_register_device);
557 
558 
559 void dvb_remove_device(struct dvb_device *dvbdev)
560 {
561 	if (!dvbdev)
562 		return;
563 
564 	down_write(&minor_rwsem);
565 	dvb_minors[dvbdev->minor] = NULL;
566 	up_write(&minor_rwsem);
567 
568 	dvb_media_device_free(dvbdev);
569 
570 	device_destroy(dvb_class, MKDEV(DVB_MAJOR, dvbdev->minor));
571 
572 	list_del (&dvbdev->list_head);
573 }
574 EXPORT_SYMBOL(dvb_remove_device);
575 
576 
577 void dvb_free_device(struct dvb_device *dvbdev)
578 {
579 	if (!dvbdev)
580 		return;
581 
582 	kfree (dvbdev->fops);
583 	kfree (dvbdev);
584 }
585 EXPORT_SYMBOL(dvb_free_device);
586 
587 
588 void dvb_unregister_device(struct dvb_device *dvbdev)
589 {
590 	dvb_remove_device(dvbdev);
591 	dvb_free_device(dvbdev);
592 }
593 EXPORT_SYMBOL(dvb_unregister_device);
594 
595 
596 #ifdef CONFIG_MEDIA_CONTROLLER_DVB
597 
598 static int dvb_create_io_intf_links(struct dvb_adapter *adap,
599 				    struct media_interface *intf,
600 				    char *name)
601 {
602 	struct media_device *mdev = adap->mdev;
603 	struct media_entity *entity;
604 	struct media_link *link;
605 
606 	media_device_for_each_entity(entity, mdev) {
607 		if (entity->function == MEDIA_ENT_F_IO_DTV) {
608 			if (strncmp(entity->name, name, strlen(name)))
609 				continue;
610 			link = media_create_intf_link(entity, intf,
611 						      MEDIA_LNK_FL_ENABLED |
612 						      MEDIA_LNK_FL_IMMUTABLE);
613 			if (!link)
614 				return -ENOMEM;
615 		}
616 	}
617 	return 0;
618 }
619 
620 int dvb_create_media_graph(struct dvb_adapter *adap,
621 			   bool create_rf_connector)
622 {
623 	struct media_device *mdev = adap->mdev;
624 	struct media_entity *entity, *tuner = NULL, *demod = NULL, *conn;
625 	struct media_entity *demux = NULL, *ca = NULL;
626 	struct media_link *link;
627 	struct media_interface *intf;
628 	unsigned demux_pad = 0;
629 	unsigned dvr_pad = 0;
630 	unsigned ntuner = 0, ndemod = 0;
631 	int ret, pad_source, pad_sink;
632 	static const char *connector_name = "Television";
633 
634 	if (!mdev)
635 		return 0;
636 
637 	media_device_for_each_entity(entity, mdev) {
638 		switch (entity->function) {
639 		case MEDIA_ENT_F_TUNER:
640 			tuner = entity;
641 			ntuner++;
642 			break;
643 		case MEDIA_ENT_F_DTV_DEMOD:
644 			demod = entity;
645 			ndemod++;
646 			break;
647 		case MEDIA_ENT_F_TS_DEMUX:
648 			demux = entity;
649 			break;
650 		case MEDIA_ENT_F_DTV_CA:
651 			ca = entity;
652 			break;
653 		}
654 	}
655 
656 	/*
657 	 * Prepare to signalize to media_create_pad_links() that multiple
658 	 * entities of the same type exists and a 1:n or n:1 links need to be
659 	 * created.
660 	 * NOTE: if both tuner and demod have multiple instances, it is up
661 	 * to the caller driver to create such links.
662 	 */
663 	if (ntuner > 1)
664 		tuner = NULL;
665 	if (ndemod > 1)
666 		demod = NULL;
667 
668 	if (create_rf_connector) {
669 		conn = kzalloc(sizeof(*conn), GFP_KERNEL);
670 		if (!conn)
671 			return -ENOMEM;
672 		adap->conn = conn;
673 
674 		adap->conn_pads = kzalloc(sizeof(*adap->conn_pads), GFP_KERNEL);
675 		if (!adap->conn_pads)
676 			return -ENOMEM;
677 
678 		conn->flags = MEDIA_ENT_FL_CONNECTOR;
679 		conn->function = MEDIA_ENT_F_CONN_RF;
680 		conn->name = connector_name;
681 		adap->conn_pads->flags = MEDIA_PAD_FL_SOURCE;
682 
683 		ret = media_entity_pads_init(conn, 1, adap->conn_pads);
684 		if (ret)
685 			return ret;
686 
687 		ret = media_device_register_entity(mdev, conn);
688 		if (ret)
689 			return ret;
690 
691 		if (!ntuner) {
692 			ret = media_create_pad_links(mdev,
693 						     MEDIA_ENT_F_CONN_RF,
694 						     conn, 0,
695 						     MEDIA_ENT_F_DTV_DEMOD,
696 						     demod, 0,
697 						     MEDIA_LNK_FL_ENABLED,
698 						     false);
699 		} else {
700 			pad_sink = media_get_pad_index(tuner, true,
701 						       PAD_SIGNAL_ANALOG);
702 			if (pad_sink < 0)
703 				return -EINVAL;
704 			ret = media_create_pad_links(mdev,
705 						     MEDIA_ENT_F_CONN_RF,
706 						     conn, 0,
707 						     MEDIA_ENT_F_TUNER,
708 						     tuner, pad_sink,
709 						     MEDIA_LNK_FL_ENABLED,
710 						     false);
711 		}
712 		if (ret)
713 			return ret;
714 	}
715 
716 	if (ntuner && ndemod) {
717 		/* NOTE: first found tuner source pad presumed correct */
718 		pad_source = media_get_pad_index(tuner, false,
719 						 PAD_SIGNAL_ANALOG);
720 		if (pad_source < 0)
721 			return -EINVAL;
722 		ret = media_create_pad_links(mdev,
723 					     MEDIA_ENT_F_TUNER,
724 					     tuner, pad_source,
725 					     MEDIA_ENT_F_DTV_DEMOD,
726 					     demod, 0, MEDIA_LNK_FL_ENABLED,
727 					     false);
728 		if (ret)
729 			return ret;
730 	}
731 
732 	if (ndemod && demux) {
733 		ret = media_create_pad_links(mdev,
734 					     MEDIA_ENT_F_DTV_DEMOD,
735 					     demod, 1,
736 					     MEDIA_ENT_F_TS_DEMUX,
737 					     demux, 0, MEDIA_LNK_FL_ENABLED,
738 					     false);
739 		if (ret)
740 			return ret;
741 	}
742 	if (demux && ca) {
743 		ret = media_create_pad_link(demux, 1, ca,
744 					    0, MEDIA_LNK_FL_ENABLED);
745 		if (ret)
746 			return ret;
747 	}
748 
749 	/* Create demux links for each ringbuffer/pad */
750 	if (demux) {
751 		media_device_for_each_entity(entity, mdev) {
752 			if (entity->function == MEDIA_ENT_F_IO_DTV) {
753 				if (!strncmp(entity->name, DVR_TSOUT,
754 				    strlen(DVR_TSOUT))) {
755 					ret = media_create_pad_link(demux,
756 								++dvr_pad,
757 							    entity, 0, 0);
758 					if (ret)
759 						return ret;
760 				}
761 				if (!strncmp(entity->name, DEMUX_TSOUT,
762 				    strlen(DEMUX_TSOUT))) {
763 					ret = media_create_pad_link(demux,
764 							      ++demux_pad,
765 							    entity, 0, 0);
766 					if (ret)
767 						return ret;
768 				}
769 			}
770 		}
771 	}
772 
773 	/* Create interface links for FE->tuner, DVR->demux and CA->ca */
774 	media_device_for_each_intf(intf, mdev) {
775 		if (intf->type == MEDIA_INTF_T_DVB_CA && ca) {
776 			link = media_create_intf_link(ca, intf,
777 						      MEDIA_LNK_FL_ENABLED |
778 						      MEDIA_LNK_FL_IMMUTABLE);
779 			if (!link)
780 				return -ENOMEM;
781 		}
782 
783 		if (intf->type == MEDIA_INTF_T_DVB_FE && tuner) {
784 			link = media_create_intf_link(tuner, intf,
785 						      MEDIA_LNK_FL_ENABLED |
786 						      MEDIA_LNK_FL_IMMUTABLE);
787 			if (!link)
788 				return -ENOMEM;
789 		}
790 #if 0
791 		/*
792 		 * Indirect link - let's not create yet, as we don't know how
793 		 *		   to handle indirect links, nor if this will
794 		 *		   actually be needed.
795 		 */
796 		if (intf->type == MEDIA_INTF_T_DVB_DVR && demux) {
797 			link = media_create_intf_link(demux, intf,
798 						      MEDIA_LNK_FL_ENABLED |
799 						      MEDIA_LNK_FL_IMMUTABLE);
800 			if (!link)
801 				return -ENOMEM;
802 		}
803 #endif
804 		if (intf->type == MEDIA_INTF_T_DVB_DVR) {
805 			ret = dvb_create_io_intf_links(adap, intf, DVR_TSOUT);
806 			if (ret)
807 				return ret;
808 		}
809 		if (intf->type == MEDIA_INTF_T_DVB_DEMUX) {
810 			ret = dvb_create_io_intf_links(adap, intf, DEMUX_TSOUT);
811 			if (ret)
812 				return ret;
813 		}
814 	}
815 	return 0;
816 }
817 EXPORT_SYMBOL_GPL(dvb_create_media_graph);
818 #endif
819 
820 static int dvbdev_check_free_adapter_num(int num)
821 {
822 	struct list_head *entry;
823 	list_for_each(entry, &dvb_adapter_list) {
824 		struct dvb_adapter *adap;
825 		adap = list_entry(entry, struct dvb_adapter, list_head);
826 		if (adap->num == num)
827 			return 0;
828 	}
829 	return 1;
830 }
831 
832 static int dvbdev_get_free_adapter_num (void)
833 {
834 	int num = 0;
835 
836 	while (num < DVB_MAX_ADAPTERS) {
837 		if (dvbdev_check_free_adapter_num(num))
838 			return num;
839 		num++;
840 	}
841 
842 	return -ENFILE;
843 }
844 
845 
846 int dvb_register_adapter(struct dvb_adapter *adap, const char *name,
847 			 struct module *module, struct device *device,
848 			 short *adapter_nums)
849 {
850 	int i, num;
851 
852 	mutex_lock(&dvbdev_register_lock);
853 
854 	for (i = 0; i < DVB_MAX_ADAPTERS; ++i) {
855 		num = adapter_nums[i];
856 		if (num >= 0  &&  num < DVB_MAX_ADAPTERS) {
857 		/* use the one the driver asked for */
858 			if (dvbdev_check_free_adapter_num(num))
859 				break;
860 		} else {
861 			num = dvbdev_get_free_adapter_num();
862 			break;
863 		}
864 		num = -1;
865 	}
866 
867 	if (num < 0) {
868 		mutex_unlock(&dvbdev_register_lock);
869 		return -ENFILE;
870 	}
871 
872 	memset (adap, 0, sizeof(struct dvb_adapter));
873 	INIT_LIST_HEAD (&adap->device_list);
874 
875 	pr_info("DVB: registering new adapter (%s)\n", name);
876 
877 	adap->num = num;
878 	adap->name = name;
879 	adap->module = module;
880 	adap->device = device;
881 	adap->mfe_shared = 0;
882 	adap->mfe_dvbdev = NULL;
883 	mutex_init (&adap->mfe_lock);
884 
885 #ifdef CONFIG_MEDIA_CONTROLLER_DVB
886 	mutex_init(&adap->mdev_lock);
887 #endif
888 
889 	list_add_tail (&adap->list_head, &dvb_adapter_list);
890 
891 	mutex_unlock(&dvbdev_register_lock);
892 
893 	return num;
894 }
895 EXPORT_SYMBOL(dvb_register_adapter);
896 
897 
898 int dvb_unregister_adapter(struct dvb_adapter *adap)
899 {
900 	mutex_lock(&dvbdev_register_lock);
901 	list_del (&adap->list_head);
902 	mutex_unlock(&dvbdev_register_lock);
903 	return 0;
904 }
905 EXPORT_SYMBOL(dvb_unregister_adapter);
906 
907 /* if the miracle happens and "generic_usercopy()" is included into
908    the kernel, then this can vanish. please don't make the mistake and
909    define this as video_usercopy(). this will introduce a dependency
910    to the v4l "videodev.o" module, which is unnecessary for some
911    cards (ie. the budget dvb-cards don't need the v4l module...) */
912 int dvb_usercopy(struct file *file,
913 		     unsigned int cmd, unsigned long arg,
914 		     int (*func)(struct file *file,
915 		     unsigned int cmd, void *arg))
916 {
917 	char    sbuf[128];
918 	void    *mbuf = NULL;
919 	void    *parg = NULL;
920 	int     err  = -EINVAL;
921 
922 	/*  Copy arguments into temp kernel buffer  */
923 	switch (_IOC_DIR(cmd)) {
924 	case _IOC_NONE:
925 		/*
926 		 * For this command, the pointer is actually an integer
927 		 * argument.
928 		 */
929 		parg = (void *) arg;
930 		break;
931 	case _IOC_READ: /* some v4l ioctls are marked wrong ... */
932 	case _IOC_WRITE:
933 	case (_IOC_WRITE | _IOC_READ):
934 		if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
935 			parg = sbuf;
936 		} else {
937 			/* too big to allocate from stack */
938 			mbuf = kmalloc(_IOC_SIZE(cmd), GFP_KERNEL);
939 			if (NULL == mbuf)
940 				return -ENOMEM;
941 			parg = mbuf;
942 		}
943 
944 		err = -EFAULT;
945 		if (copy_from_user(parg, (void __user *)arg, _IOC_SIZE(cmd)))
946 			goto out;
947 		break;
948 	}
949 
950 	/* call driver */
951 	if ((err = func(file, cmd, parg)) == -ENOIOCTLCMD)
952 		err = -ENOTTY;
953 
954 	if (err < 0)
955 		goto out;
956 
957 	/*  Copy results into user buffer  */
958 	switch (_IOC_DIR(cmd))
959 	{
960 	case _IOC_READ:
961 	case (_IOC_WRITE | _IOC_READ):
962 		if (copy_to_user((void __user *)arg, parg, _IOC_SIZE(cmd)))
963 			err = -EFAULT;
964 		break;
965 	}
966 
967 out:
968 	kfree(mbuf);
969 	return err;
970 }
971 
972 #if IS_ENABLED(CONFIG_I2C)
973 struct i2c_client *dvb_module_probe(const char *module_name,
974 				    const char *name,
975 				    struct i2c_adapter *adap,
976 				    unsigned char addr,
977 				    void *platform_data)
978 {
979 	struct i2c_client *client;
980 	struct i2c_board_info *board_info;
981 
982 	board_info = kzalloc(sizeof(*board_info), GFP_KERNEL);
983 	if (!board_info)
984 		return NULL;
985 
986 	if (name)
987 		strscpy(board_info->type, name, I2C_NAME_SIZE);
988 	else
989 		strscpy(board_info->type, module_name, I2C_NAME_SIZE);
990 
991 	board_info->addr = addr;
992 	board_info->platform_data = platform_data;
993 	request_module(module_name);
994 	client = i2c_new_client_device(adap, board_info);
995 	if (!i2c_client_has_driver(client)) {
996 		kfree(board_info);
997 		return NULL;
998 	}
999 
1000 	if (!try_module_get(client->dev.driver->owner)) {
1001 		i2c_unregister_device(client);
1002 		client = NULL;
1003 	}
1004 
1005 	kfree(board_info);
1006 	return client;
1007 }
1008 EXPORT_SYMBOL_GPL(dvb_module_probe);
1009 
1010 void dvb_module_release(struct i2c_client *client)
1011 {
1012 	if (!client)
1013 		return;
1014 
1015 	module_put(client->dev.driver->owner);
1016 	i2c_unregister_device(client);
1017 }
1018 EXPORT_SYMBOL_GPL(dvb_module_release);
1019 #endif
1020 
1021 static int dvb_uevent(struct device *dev, struct kobj_uevent_env *env)
1022 {
1023 	struct dvb_device *dvbdev = dev_get_drvdata(dev);
1024 
1025 	add_uevent_var(env, "DVB_ADAPTER_NUM=%d", dvbdev->adapter->num);
1026 	add_uevent_var(env, "DVB_DEVICE_TYPE=%s", dnames[dvbdev->type]);
1027 	add_uevent_var(env, "DVB_DEVICE_NUM=%d", dvbdev->id);
1028 	return 0;
1029 }
1030 
1031 static char *dvb_devnode(struct device *dev, umode_t *mode)
1032 {
1033 	struct dvb_device *dvbdev = dev_get_drvdata(dev);
1034 
1035 	return kasprintf(GFP_KERNEL, "dvb/adapter%d/%s%d",
1036 		dvbdev->adapter->num, dnames[dvbdev->type], dvbdev->id);
1037 }
1038 
1039 
1040 static int __init init_dvbdev(void)
1041 {
1042 	int retval;
1043 	dev_t dev = MKDEV(DVB_MAJOR, 0);
1044 
1045 	if ((retval = register_chrdev_region(dev, MAX_DVB_MINORS, "DVB")) != 0) {
1046 		pr_err("dvb-core: unable to get major %d\n", DVB_MAJOR);
1047 		return retval;
1048 	}
1049 
1050 	cdev_init(&dvb_device_cdev, &dvb_device_fops);
1051 	if ((retval = cdev_add(&dvb_device_cdev, dev, MAX_DVB_MINORS)) != 0) {
1052 		pr_err("dvb-core: unable register character device\n");
1053 		goto error;
1054 	}
1055 
1056 	dvb_class = class_create(THIS_MODULE, "dvb");
1057 	if (IS_ERR(dvb_class)) {
1058 		retval = PTR_ERR(dvb_class);
1059 		goto error;
1060 	}
1061 	dvb_class->dev_uevent = dvb_uevent;
1062 	dvb_class->devnode = dvb_devnode;
1063 	return 0;
1064 
1065 error:
1066 	cdev_del(&dvb_device_cdev);
1067 	unregister_chrdev_region(dev, MAX_DVB_MINORS);
1068 	return retval;
1069 }
1070 
1071 
1072 static void __exit exit_dvbdev(void)
1073 {
1074 	class_destroy(dvb_class);
1075 	cdev_del(&dvb_device_cdev);
1076 	unregister_chrdev_region(MKDEV(DVB_MAJOR, 0), MAX_DVB_MINORS);
1077 }
1078 
1079 subsys_initcall(init_dvbdev);
1080 module_exit(exit_dvbdev);
1081 
1082 MODULE_DESCRIPTION("DVB Core Driver");
1083 MODULE_AUTHOR("Marcus Metzler, Ralph Metzler, Holger Waechtler");
1084 MODULE_LICENSE("GPL");
1085