xref: /linux/drivers/media/dvb-core/dvbdev.c (revision f1409116835a8ae7cd924e2829772c470eb6cba4)
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 		dvbdev->adapter->conn = NULL;
245 		kfree(dvbdev->adapter->conn_pads);
246 		dvbdev->adapter->conn_pads = NULL;
247 	}
248 #endif
249 }
250 
251 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
252 static int dvb_create_tsout_entity(struct dvb_device *dvbdev,
253 				    const char *name, int npads)
254 {
255 	int i, ret = 0;
256 
257 	dvbdev->tsout_pads = kcalloc(npads, sizeof(*dvbdev->tsout_pads),
258 				     GFP_KERNEL);
259 	if (!dvbdev->tsout_pads)
260 		return -ENOMEM;
261 
262 	dvbdev->tsout_entity = kcalloc(npads, sizeof(*dvbdev->tsout_entity),
263 				       GFP_KERNEL);
264 	if (!dvbdev->tsout_entity)
265 		return -ENOMEM;
266 
267 	dvbdev->tsout_num_entities = npads;
268 
269 	for (i = 0; i < npads; i++) {
270 		struct media_pad *pads = &dvbdev->tsout_pads[i];
271 		struct media_entity *entity = &dvbdev->tsout_entity[i];
272 
273 		entity->name = kasprintf(GFP_KERNEL, "%s #%d", name, i);
274 		if (!entity->name)
275 			return -ENOMEM;
276 
277 		entity->function = MEDIA_ENT_F_IO_DTV;
278 		pads->flags = MEDIA_PAD_FL_SINK;
279 
280 		ret = media_entity_pads_init(entity, 1, pads);
281 		if (ret < 0)
282 			return ret;
283 
284 		ret = media_device_register_entity(dvbdev->adapter->mdev,
285 						   entity);
286 		if (ret < 0)
287 			return ret;
288 	}
289 	return 0;
290 }
291 
292 #define DEMUX_TSOUT	"demux-tsout"
293 #define DVR_TSOUT	"dvr-tsout"
294 
295 static int dvb_create_media_entity(struct dvb_device *dvbdev,
296 				   int type, int demux_sink_pads)
297 {
298 	int i, ret, npads;
299 
300 	switch (type) {
301 	case DVB_DEVICE_FRONTEND:
302 		npads = 2;
303 		break;
304 	case DVB_DEVICE_DVR:
305 		ret = dvb_create_tsout_entity(dvbdev, DVR_TSOUT,
306 					      demux_sink_pads);
307 		return ret;
308 	case DVB_DEVICE_DEMUX:
309 		npads = 1 + demux_sink_pads;
310 		ret = dvb_create_tsout_entity(dvbdev, DEMUX_TSOUT,
311 					      demux_sink_pads);
312 		if (ret < 0)
313 			return ret;
314 		break;
315 	case DVB_DEVICE_CA:
316 		npads = 2;
317 		break;
318 	case DVB_DEVICE_NET:
319 		/*
320 		 * We should be creating entities for the MPE/ULE
321 		 * decapsulation hardware (or software implementation).
322 		 *
323 		 * However, the number of for the MPE/ULE decaps may not be
324 		 * fixed. As we don't have yet dynamic support for PADs at
325 		 * the Media Controller, let's not create the decap
326 		 * entities yet.
327 		 */
328 		return 0;
329 	default:
330 		return 0;
331 	}
332 
333 	dvbdev->entity = kzalloc(sizeof(*dvbdev->entity), GFP_KERNEL);
334 	if (!dvbdev->entity)
335 		return -ENOMEM;
336 
337 	dvbdev->entity->name = dvbdev->name;
338 
339 	if (npads) {
340 		dvbdev->pads = kcalloc(npads, sizeof(*dvbdev->pads),
341 				       GFP_KERNEL);
342 		if (!dvbdev->pads)
343 			return -ENOMEM;
344 	}
345 
346 	switch (type) {
347 	case DVB_DEVICE_FRONTEND:
348 		dvbdev->entity->function = MEDIA_ENT_F_DTV_DEMOD;
349 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
350 		dvbdev->pads[1].flags = MEDIA_PAD_FL_SOURCE;
351 		break;
352 	case DVB_DEVICE_DEMUX:
353 		dvbdev->entity->function = MEDIA_ENT_F_TS_DEMUX;
354 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
355 		for (i = 1; i < npads; i++)
356 			dvbdev->pads[i].flags = MEDIA_PAD_FL_SOURCE;
357 		break;
358 	case DVB_DEVICE_CA:
359 		dvbdev->entity->function = MEDIA_ENT_F_DTV_CA;
360 		dvbdev->pads[0].flags = MEDIA_PAD_FL_SINK;
361 		dvbdev->pads[1].flags = MEDIA_PAD_FL_SOURCE;
362 		break;
363 	default:
364 		/* Should never happen, as the first switch prevents it */
365 		kfree(dvbdev->entity);
366 		kfree(dvbdev->pads);
367 		dvbdev->entity = NULL;
368 		dvbdev->pads = NULL;
369 		return 0;
370 	}
371 
372 	if (npads) {
373 		ret = media_entity_pads_init(dvbdev->entity, npads, dvbdev->pads);
374 		if (ret)
375 			return ret;
376 	}
377 	ret = media_device_register_entity(dvbdev->adapter->mdev,
378 					   dvbdev->entity);
379 	if (ret)
380 		return ret;
381 
382 	pr_info("%s: media entity '%s' registered.\n",
383 		__func__, dvbdev->entity->name);
384 
385 	return 0;
386 }
387 #endif
388 
389 static int dvb_register_media_device(struct dvb_device *dvbdev,
390 				     int type, int minor,
391 				     unsigned demux_sink_pads)
392 {
393 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
394 	struct media_link *link;
395 	u32 intf_type;
396 	int ret;
397 
398 	if (!dvbdev->adapter->mdev)
399 		return 0;
400 
401 	ret = dvb_create_media_entity(dvbdev, type, demux_sink_pads);
402 	if (ret)
403 		return ret;
404 
405 	switch (type) {
406 	case DVB_DEVICE_FRONTEND:
407 		intf_type = MEDIA_INTF_T_DVB_FE;
408 		break;
409 	case DVB_DEVICE_DEMUX:
410 		intf_type = MEDIA_INTF_T_DVB_DEMUX;
411 		break;
412 	case DVB_DEVICE_DVR:
413 		intf_type = MEDIA_INTF_T_DVB_DVR;
414 		break;
415 	case DVB_DEVICE_CA:
416 		intf_type = MEDIA_INTF_T_DVB_CA;
417 		break;
418 	case DVB_DEVICE_NET:
419 		intf_type = MEDIA_INTF_T_DVB_NET;
420 		break;
421 	default:
422 		return 0;
423 	}
424 
425 	dvbdev->intf_devnode = media_devnode_create(dvbdev->adapter->mdev,
426 						    intf_type, 0,
427 						    DVB_MAJOR, minor);
428 
429 	if (!dvbdev->intf_devnode)
430 		return -ENOMEM;
431 
432 	/*
433 	 * Create the "obvious" link, e. g. the ones that represent
434 	 * a direct association between an interface and an entity.
435 	 * Other links should be created elsewhere, like:
436 	 *		DVB FE intf    -> tuner
437 	 *		DVB demux intf -> dvr
438 	 */
439 
440 	if (!dvbdev->entity)
441 		return 0;
442 
443 	link = media_create_intf_link(dvbdev->entity,
444 				      &dvbdev->intf_devnode->intf,
445 				      MEDIA_LNK_FL_ENABLED |
446 				      MEDIA_LNK_FL_IMMUTABLE);
447 	if (!link)
448 		return -ENOMEM;
449 #endif
450 	return 0;
451 }
452 
453 int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
454 			const struct dvb_device *template, void *priv,
455 			enum dvb_device_type type, int demux_sink_pads)
456 {
457 	struct dvb_device *dvbdev;
458 	struct file_operations *dvbdevfops;
459 	struct device *clsdev;
460 	int minor;
461 	int id, ret;
462 
463 	mutex_lock(&dvbdev_register_lock);
464 
465 	if ((id = dvbdev_get_free_id (adap, type)) < 0){
466 		mutex_unlock(&dvbdev_register_lock);
467 		*pdvbdev = NULL;
468 		pr_err("%s: couldn't find free device id\n", __func__);
469 		return -ENFILE;
470 	}
471 
472 	*pdvbdev = dvbdev = kzalloc(sizeof(*dvbdev), GFP_KERNEL);
473 
474 	if (!dvbdev){
475 		mutex_unlock(&dvbdev_register_lock);
476 		return -ENOMEM;
477 	}
478 
479 	dvbdevfops = kmemdup(template->fops, sizeof(*dvbdevfops), GFP_KERNEL);
480 
481 	if (!dvbdevfops){
482 		kfree (dvbdev);
483 		mutex_unlock(&dvbdev_register_lock);
484 		return -ENOMEM;
485 	}
486 
487 	memcpy(dvbdev, template, sizeof(struct dvb_device));
488 	dvbdev->type = type;
489 	dvbdev->id = id;
490 	dvbdev->adapter = adap;
491 	dvbdev->priv = priv;
492 	dvbdev->fops = dvbdevfops;
493 	init_waitqueue_head (&dvbdev->wait_queue);
494 
495 	dvbdevfops->owner = adap->module;
496 
497 	list_add_tail (&dvbdev->list_head, &adap->device_list);
498 
499 	down_write(&minor_rwsem);
500 #ifdef CONFIG_DVB_DYNAMIC_MINORS
501 	for (minor = 0; minor < MAX_DVB_MINORS; minor++)
502 		if (dvb_minors[minor] == NULL)
503 			break;
504 
505 	if (minor == MAX_DVB_MINORS) {
506 		kfree(dvbdevfops);
507 		kfree(dvbdev);
508 		up_write(&minor_rwsem);
509 		mutex_unlock(&dvbdev_register_lock);
510 		return -EINVAL;
511 	}
512 #else
513 	minor = nums2minor(adap->num, type, id);
514 #endif
515 
516 	dvbdev->minor = minor;
517 	dvb_minors[minor] = dvbdev;
518 	up_write(&minor_rwsem);
519 
520 	ret = dvb_register_media_device(dvbdev, type, minor, demux_sink_pads);
521 	if (ret) {
522 		pr_err("%s: dvb_register_media_device failed to create the mediagraph\n",
523 		      __func__);
524 
525 		dvb_media_device_free(dvbdev);
526 		kfree(dvbdevfops);
527 		kfree(dvbdev);
528 		mutex_unlock(&dvbdev_register_lock);
529 		return ret;
530 	}
531 
532 	mutex_unlock(&dvbdev_register_lock);
533 
534 	clsdev = device_create(dvb_class, adap->device,
535 			       MKDEV(DVB_MAJOR, minor),
536 			       dvbdev, "dvb%d.%s%d", adap->num, dnames[type], id);
537 	if (IS_ERR(clsdev)) {
538 		pr_err("%s: failed to create device dvb%d.%s%d (%ld)\n",
539 		       __func__, adap->num, dnames[type], id, PTR_ERR(clsdev));
540 		return PTR_ERR(clsdev);
541 	}
542 	dprintk("DVB: register adapter%d/%s%d @ minor: %i (0x%02x)\n",
543 		adap->num, dnames[type], id, minor, minor);
544 
545 	return 0;
546 }
547 EXPORT_SYMBOL(dvb_register_device);
548 
549 
550 void dvb_remove_device(struct dvb_device *dvbdev)
551 {
552 	if (!dvbdev)
553 		return;
554 
555 	down_write(&minor_rwsem);
556 	dvb_minors[dvbdev->minor] = NULL;
557 	up_write(&minor_rwsem);
558 
559 	dvb_media_device_free(dvbdev);
560 
561 	device_destroy(dvb_class, MKDEV(DVB_MAJOR, dvbdev->minor));
562 
563 	list_del (&dvbdev->list_head);
564 }
565 EXPORT_SYMBOL(dvb_remove_device);
566 
567 
568 void dvb_free_device(struct dvb_device *dvbdev)
569 {
570 	if (!dvbdev)
571 		return;
572 
573 	kfree (dvbdev->fops);
574 	kfree (dvbdev);
575 }
576 EXPORT_SYMBOL(dvb_free_device);
577 
578 
579 void dvb_unregister_device(struct dvb_device *dvbdev)
580 {
581 	dvb_remove_device(dvbdev);
582 	dvb_free_device(dvbdev);
583 }
584 EXPORT_SYMBOL(dvb_unregister_device);
585 
586 
587 #ifdef CONFIG_MEDIA_CONTROLLER_DVB
588 
589 static int dvb_create_io_intf_links(struct dvb_adapter *adap,
590 				    struct media_interface *intf,
591 				    char *name)
592 {
593 	struct media_device *mdev = adap->mdev;
594 	struct media_entity *entity;
595 	struct media_link *link;
596 
597 	media_device_for_each_entity(entity, mdev) {
598 		if (entity->function == MEDIA_ENT_F_IO_DTV) {
599 			if (strncmp(entity->name, name, strlen(name)))
600 				continue;
601 			link = media_create_intf_link(entity, intf,
602 						      MEDIA_LNK_FL_ENABLED |
603 						      MEDIA_LNK_FL_IMMUTABLE);
604 			if (!link)
605 				return -ENOMEM;
606 		}
607 	}
608 	return 0;
609 }
610 
611 int dvb_create_media_graph(struct dvb_adapter *adap,
612 			   bool create_rf_connector)
613 {
614 	struct media_device *mdev = adap->mdev;
615 	struct media_entity *entity, *tuner = NULL, *demod = NULL, *conn;
616 	struct media_entity *demux = NULL, *ca = NULL;
617 	struct media_link *link;
618 	struct media_interface *intf;
619 	unsigned demux_pad = 0;
620 	unsigned dvr_pad = 0;
621 	unsigned ntuner = 0, ndemod = 0;
622 	int ret, pad_source, pad_sink;
623 	static const char *connector_name = "Television";
624 
625 	if (!mdev)
626 		return 0;
627 
628 	media_device_for_each_entity(entity, mdev) {
629 		switch (entity->function) {
630 		case MEDIA_ENT_F_TUNER:
631 			tuner = entity;
632 			ntuner++;
633 			break;
634 		case MEDIA_ENT_F_DTV_DEMOD:
635 			demod = entity;
636 			ndemod++;
637 			break;
638 		case MEDIA_ENT_F_TS_DEMUX:
639 			demux = entity;
640 			break;
641 		case MEDIA_ENT_F_DTV_CA:
642 			ca = entity;
643 			break;
644 		}
645 	}
646 
647 	/*
648 	 * Prepare to signalize to media_create_pad_links() that multiple
649 	 * entities of the same type exists and a 1:n or n:1 links need to be
650 	 * created.
651 	 * NOTE: if both tuner and demod have multiple instances, it is up
652 	 * to the caller driver to create such links.
653 	 */
654 	if (ntuner > 1)
655 		tuner = NULL;
656 	if (ndemod > 1)
657 		demod = NULL;
658 
659 	if (create_rf_connector) {
660 		conn = kzalloc(sizeof(*conn), GFP_KERNEL);
661 		if (!conn)
662 			return -ENOMEM;
663 		adap->conn = conn;
664 
665 		adap->conn_pads = kzalloc(sizeof(*adap->conn_pads), GFP_KERNEL);
666 		if (!adap->conn_pads)
667 			return -ENOMEM;
668 
669 		conn->flags = MEDIA_ENT_FL_CONNECTOR;
670 		conn->function = MEDIA_ENT_F_CONN_RF;
671 		conn->name = connector_name;
672 		adap->conn_pads->flags = MEDIA_PAD_FL_SOURCE;
673 
674 		ret = media_entity_pads_init(conn, 1, adap->conn_pads);
675 		if (ret)
676 			return ret;
677 
678 		ret = media_device_register_entity(mdev, conn);
679 		if (ret)
680 			return ret;
681 
682 		if (!ntuner) {
683 			ret = media_create_pad_links(mdev,
684 						     MEDIA_ENT_F_CONN_RF,
685 						     conn, 0,
686 						     MEDIA_ENT_F_DTV_DEMOD,
687 						     demod, 0,
688 						     MEDIA_LNK_FL_ENABLED,
689 						     false);
690 		} else {
691 			pad_sink = media_get_pad_index(tuner, true,
692 						       PAD_SIGNAL_ANALOG);
693 			if (pad_sink < 0)
694 				return -EINVAL;
695 			ret = media_create_pad_links(mdev,
696 						     MEDIA_ENT_F_CONN_RF,
697 						     conn, 0,
698 						     MEDIA_ENT_F_TUNER,
699 						     tuner, pad_sink,
700 						     MEDIA_LNK_FL_ENABLED,
701 						     false);
702 		}
703 		if (ret)
704 			return ret;
705 	}
706 
707 	if (ntuner && ndemod) {
708 		pad_source = media_get_pad_index(tuner, true,
709 						 PAD_SIGNAL_ANALOG);
710 		if (pad_source)
711 			return -EINVAL;
712 		ret = media_create_pad_links(mdev,
713 					     MEDIA_ENT_F_TUNER,
714 					     tuner, pad_source,
715 					     MEDIA_ENT_F_DTV_DEMOD,
716 					     demod, 0, MEDIA_LNK_FL_ENABLED,
717 					     false);
718 		if (ret)
719 			return ret;
720 	}
721 
722 	if (ndemod && demux) {
723 		ret = media_create_pad_links(mdev,
724 					     MEDIA_ENT_F_DTV_DEMOD,
725 					     demod, 1,
726 					     MEDIA_ENT_F_TS_DEMUX,
727 					     demux, 0, MEDIA_LNK_FL_ENABLED,
728 					     false);
729 		if (ret)
730 			return ret;
731 	}
732 	if (demux && ca) {
733 		ret = media_create_pad_link(demux, 1, ca,
734 					    0, MEDIA_LNK_FL_ENABLED);
735 		if (ret)
736 			return ret;
737 	}
738 
739 	/* Create demux links for each ringbuffer/pad */
740 	if (demux) {
741 		media_device_for_each_entity(entity, mdev) {
742 			if (entity->function == MEDIA_ENT_F_IO_DTV) {
743 				if (!strncmp(entity->name, DVR_TSOUT,
744 				    strlen(DVR_TSOUT))) {
745 					ret = media_create_pad_link(demux,
746 								++dvr_pad,
747 							    entity, 0, 0);
748 					if (ret)
749 						return ret;
750 				}
751 				if (!strncmp(entity->name, DEMUX_TSOUT,
752 				    strlen(DEMUX_TSOUT))) {
753 					ret = media_create_pad_link(demux,
754 							      ++demux_pad,
755 							    entity, 0, 0);
756 					if (ret)
757 						return ret;
758 				}
759 			}
760 		}
761 	}
762 
763 	/* Create interface links for FE->tuner, DVR->demux and CA->ca */
764 	media_device_for_each_intf(intf, mdev) {
765 		if (intf->type == MEDIA_INTF_T_DVB_CA && ca) {
766 			link = media_create_intf_link(ca, intf,
767 						      MEDIA_LNK_FL_ENABLED |
768 						      MEDIA_LNK_FL_IMMUTABLE);
769 			if (!link)
770 				return -ENOMEM;
771 		}
772 
773 		if (intf->type == MEDIA_INTF_T_DVB_FE && tuner) {
774 			link = media_create_intf_link(tuner, intf,
775 						      MEDIA_LNK_FL_ENABLED |
776 						      MEDIA_LNK_FL_IMMUTABLE);
777 			if (!link)
778 				return -ENOMEM;
779 		}
780 #if 0
781 		/*
782 		 * Indirect link - let's not create yet, as we don't know how
783 		 *		   to handle indirect links, nor if this will
784 		 *		   actually be needed.
785 		 */
786 		if (intf->type == MEDIA_INTF_T_DVB_DVR && demux) {
787 			link = media_create_intf_link(demux, intf,
788 						      MEDIA_LNK_FL_ENABLED |
789 						      MEDIA_LNK_FL_IMMUTABLE);
790 			if (!link)
791 				return -ENOMEM;
792 		}
793 #endif
794 		if (intf->type == MEDIA_INTF_T_DVB_DVR) {
795 			ret = dvb_create_io_intf_links(adap, intf, DVR_TSOUT);
796 			if (ret)
797 				return ret;
798 		}
799 		if (intf->type == MEDIA_INTF_T_DVB_DEMUX) {
800 			ret = dvb_create_io_intf_links(adap, intf, DEMUX_TSOUT);
801 			if (ret)
802 				return ret;
803 		}
804 	}
805 	return 0;
806 }
807 EXPORT_SYMBOL_GPL(dvb_create_media_graph);
808 #endif
809 
810 static int dvbdev_check_free_adapter_num(int num)
811 {
812 	struct list_head *entry;
813 	list_for_each(entry, &dvb_adapter_list) {
814 		struct dvb_adapter *adap;
815 		adap = list_entry(entry, struct dvb_adapter, list_head);
816 		if (adap->num == num)
817 			return 0;
818 	}
819 	return 1;
820 }
821 
822 static int dvbdev_get_free_adapter_num (void)
823 {
824 	int num = 0;
825 
826 	while (num < DVB_MAX_ADAPTERS) {
827 		if (dvbdev_check_free_adapter_num(num))
828 			return num;
829 		num++;
830 	}
831 
832 	return -ENFILE;
833 }
834 
835 
836 int dvb_register_adapter(struct dvb_adapter *adap, const char *name,
837 			 struct module *module, struct device *device,
838 			 short *adapter_nums)
839 {
840 	int i, num;
841 
842 	mutex_lock(&dvbdev_register_lock);
843 
844 	for (i = 0; i < DVB_MAX_ADAPTERS; ++i) {
845 		num = adapter_nums[i];
846 		if (num >= 0  &&  num < DVB_MAX_ADAPTERS) {
847 		/* use the one the driver asked for */
848 			if (dvbdev_check_free_adapter_num(num))
849 				break;
850 		} else {
851 			num = dvbdev_get_free_adapter_num();
852 			break;
853 		}
854 		num = -1;
855 	}
856 
857 	if (num < 0) {
858 		mutex_unlock(&dvbdev_register_lock);
859 		return -ENFILE;
860 	}
861 
862 	memset (adap, 0, sizeof(struct dvb_adapter));
863 	INIT_LIST_HEAD (&adap->device_list);
864 
865 	pr_info("DVB: registering new adapter (%s)\n", name);
866 
867 	adap->num = num;
868 	adap->name = name;
869 	adap->module = module;
870 	adap->device = device;
871 	adap->mfe_shared = 0;
872 	adap->mfe_dvbdev = NULL;
873 	mutex_init (&adap->mfe_lock);
874 
875 #ifdef CONFIG_MEDIA_CONTROLLER_DVB
876 	mutex_init(&adap->mdev_lock);
877 #endif
878 
879 	list_add_tail (&adap->list_head, &dvb_adapter_list);
880 
881 	mutex_unlock(&dvbdev_register_lock);
882 
883 	return num;
884 }
885 EXPORT_SYMBOL(dvb_register_adapter);
886 
887 
888 int dvb_unregister_adapter(struct dvb_adapter *adap)
889 {
890 	mutex_lock(&dvbdev_register_lock);
891 	list_del (&adap->list_head);
892 	mutex_unlock(&dvbdev_register_lock);
893 	return 0;
894 }
895 EXPORT_SYMBOL(dvb_unregister_adapter);
896 
897 /* if the miracle happens and "generic_usercopy()" is included into
898    the kernel, then this can vanish. please don't make the mistake and
899    define this as video_usercopy(). this will introduce a dependency
900    to the v4l "videodev.o" module, which is unnecessary for some
901    cards (ie. the budget dvb-cards don't need the v4l module...) */
902 int dvb_usercopy(struct file *file,
903 		     unsigned int cmd, unsigned long arg,
904 		     int (*func)(struct file *file,
905 		     unsigned int cmd, void *arg))
906 {
907 	char    sbuf[128];
908 	void    *mbuf = NULL;
909 	void    *parg = NULL;
910 	int     err  = -EINVAL;
911 
912 	/*  Copy arguments into temp kernel buffer  */
913 	switch (_IOC_DIR(cmd)) {
914 	case _IOC_NONE:
915 		/*
916 		 * For this command, the pointer is actually an integer
917 		 * argument.
918 		 */
919 		parg = (void *) arg;
920 		break;
921 	case _IOC_READ: /* some v4l ioctls are marked wrong ... */
922 	case _IOC_WRITE:
923 	case (_IOC_WRITE | _IOC_READ):
924 		if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
925 			parg = sbuf;
926 		} else {
927 			/* too big to allocate from stack */
928 			mbuf = kmalloc(_IOC_SIZE(cmd), GFP_KERNEL);
929 			if (NULL == mbuf)
930 				return -ENOMEM;
931 			parg = mbuf;
932 		}
933 
934 		err = -EFAULT;
935 		if (copy_from_user(parg, (void __user *)arg, _IOC_SIZE(cmd)))
936 			goto out;
937 		break;
938 	}
939 
940 	/* call driver */
941 	if ((err = func(file, cmd, parg)) == -ENOIOCTLCMD)
942 		err = -ENOTTY;
943 
944 	if (err < 0)
945 		goto out;
946 
947 	/*  Copy results into user buffer  */
948 	switch (_IOC_DIR(cmd))
949 	{
950 	case _IOC_READ:
951 	case (_IOC_WRITE | _IOC_READ):
952 		if (copy_to_user((void __user *)arg, parg, _IOC_SIZE(cmd)))
953 			err = -EFAULT;
954 		break;
955 	}
956 
957 out:
958 	kfree(mbuf);
959 	return err;
960 }
961 
962 #if IS_ENABLED(CONFIG_I2C)
963 struct i2c_client *dvb_module_probe(const char *module_name,
964 				    const char *name,
965 				    struct i2c_adapter *adap,
966 				    unsigned char addr,
967 				    void *platform_data)
968 {
969 	struct i2c_client *client;
970 	struct i2c_board_info *board_info;
971 
972 	board_info = kzalloc(sizeof(*board_info), GFP_KERNEL);
973 	if (!board_info)
974 		return NULL;
975 
976 	if (name)
977 		strscpy(board_info->type, name, I2C_NAME_SIZE);
978 	else
979 		strscpy(board_info->type, module_name, I2C_NAME_SIZE);
980 
981 	board_info->addr = addr;
982 	board_info->platform_data = platform_data;
983 	request_module(module_name);
984 	client = i2c_new_device(adap, board_info);
985 	if (client == NULL || client->dev.driver == NULL) {
986 		kfree(board_info);
987 		return NULL;
988 	}
989 
990 	if (!try_module_get(client->dev.driver->owner)) {
991 		i2c_unregister_device(client);
992 		client = NULL;
993 	}
994 
995 	kfree(board_info);
996 	return client;
997 }
998 EXPORT_SYMBOL_GPL(dvb_module_probe);
999 
1000 void dvb_module_release(struct i2c_client *client)
1001 {
1002 	if (!client)
1003 		return;
1004 
1005 	module_put(client->dev.driver->owner);
1006 	i2c_unregister_device(client);
1007 }
1008 EXPORT_SYMBOL_GPL(dvb_module_release);
1009 #endif
1010 
1011 static int dvb_uevent(struct device *dev, struct kobj_uevent_env *env)
1012 {
1013 	struct dvb_device *dvbdev = dev_get_drvdata(dev);
1014 
1015 	add_uevent_var(env, "DVB_ADAPTER_NUM=%d", dvbdev->adapter->num);
1016 	add_uevent_var(env, "DVB_DEVICE_TYPE=%s", dnames[dvbdev->type]);
1017 	add_uevent_var(env, "DVB_DEVICE_NUM=%d", dvbdev->id);
1018 	return 0;
1019 }
1020 
1021 static char *dvb_devnode(struct device *dev, umode_t *mode)
1022 {
1023 	struct dvb_device *dvbdev = dev_get_drvdata(dev);
1024 
1025 	return kasprintf(GFP_KERNEL, "dvb/adapter%d/%s%d",
1026 		dvbdev->adapter->num, dnames[dvbdev->type], dvbdev->id);
1027 }
1028 
1029 
1030 static int __init init_dvbdev(void)
1031 {
1032 	int retval;
1033 	dev_t dev = MKDEV(DVB_MAJOR, 0);
1034 
1035 	if ((retval = register_chrdev_region(dev, MAX_DVB_MINORS, "DVB")) != 0) {
1036 		pr_err("dvb-core: unable to get major %d\n", DVB_MAJOR);
1037 		return retval;
1038 	}
1039 
1040 	cdev_init(&dvb_device_cdev, &dvb_device_fops);
1041 	if ((retval = cdev_add(&dvb_device_cdev, dev, MAX_DVB_MINORS)) != 0) {
1042 		pr_err("dvb-core: unable register character device\n");
1043 		goto error;
1044 	}
1045 
1046 	dvb_class = class_create(THIS_MODULE, "dvb");
1047 	if (IS_ERR(dvb_class)) {
1048 		retval = PTR_ERR(dvb_class);
1049 		goto error;
1050 	}
1051 	dvb_class->dev_uevent = dvb_uevent;
1052 	dvb_class->devnode = dvb_devnode;
1053 	return 0;
1054 
1055 error:
1056 	cdev_del(&dvb_device_cdev);
1057 	unregister_chrdev_region(dev, MAX_DVB_MINORS);
1058 	return retval;
1059 }
1060 
1061 
1062 static void __exit exit_dvbdev(void)
1063 {
1064 	class_destroy(dvb_class);
1065 	cdev_del(&dvb_device_cdev);
1066 	unregister_chrdev_region(MKDEV(DVB_MAJOR, 0), MAX_DVB_MINORS);
1067 }
1068 
1069 subsys_initcall(init_dvbdev);
1070 module_exit(exit_dvbdev);
1071 
1072 MODULE_DESCRIPTION("DVB Core Driver");
1073 MODULE_AUTHOR("Marcus Metzler, Ralph Metzler, Holger Waechtler");
1074 MODULE_LICENSE("GPL");
1075