xref: /linux/drivers/media/dvb-core/dvbdev.c (revision 69050f8d6d075dc01af7a5f2f550a8067510366f)
1 // SPDX-License-Identifier: LGPL-2.1-or-later
2 /*
3  * dvbdev.c
4  *
5  * Copyright (C) 2000 Ralph  Metzler <ralph@convergence.de>
6  *                  & Marcus Metzler <marcus@convergence.de>
7  *                    for convergence integrated media GmbH
8  */
9 
10 #define pr_fmt(fmt) "dvbdev: " fmt
11 
12 #include <linux/types.h>
13 #include <linux/errno.h>
14 #include <linux/string.h>
15 #include <linux/module.h>
16 #include <linux/kernel.h>
17 #include <linux/i2c.h>
18 #include <linux/init.h>
19 #include <linux/slab.h>
20 #include <linux/device.h>
21 #include <linux/fs.h>
22 #include <linux/cdev.h>
23 #include <linux/mutex.h>
24 #include <media/dvbdev.h>
25 
26 /* Due to enum tuner_pad_index */
27 #include <media/tuner.h>
28 
29 static DEFINE_MUTEX(dvbdev_mutex);
30 static LIST_HEAD(dvbdevfops_list);
31 static int dvbdev_debug;
32 
33 module_param(dvbdev_debug, int, 0644);
34 MODULE_PARM_DESC(dvbdev_debug, "Turn on/off device debugging (default:off).");
35 
36 #define dprintk(fmt, arg...) do {					\
37 	if (dvbdev_debug)						\
38 		printk(KERN_DEBUG pr_fmt("%s: " fmt),			\
39 		       __func__, ##arg);				\
40 } while (0)
41 
42 static LIST_HEAD(dvb_adapter_list);
43 static DEFINE_MUTEX(dvbdev_register_lock);
44 
45 static const char * const dnames[] = {
46 	[DVB_DEVICE_VIDEO] =		"video",
47 	[DVB_DEVICE_AUDIO] =		"audio",
48 	[DVB_DEVICE_SEC] =		"sec",
49 	[DVB_DEVICE_FRONTEND] =		"frontend",
50 	[DVB_DEVICE_DEMUX] =		"demux",
51 	[DVB_DEVICE_DVR] =		"dvr",
52 	[DVB_DEVICE_CA] =		"ca",
53 	[DVB_DEVICE_NET] =		"net",
54 	[DVB_DEVICE_OSD] =		"osd"
55 };
56 
57 #ifdef CONFIG_DVB_DYNAMIC_MINORS
58 #define MAX_DVB_MINORS		256
59 #define DVB_MAX_IDS		MAX_DVB_MINORS
60 #else
61 #define DVB_MAX_IDS		4
62 
63 static const u8 minor_type[] = {
64 	[DVB_DEVICE_VIDEO]      = 0,
65 	[DVB_DEVICE_AUDIO]      = 1,
66 	[DVB_DEVICE_SEC]        = 2,
67 	[DVB_DEVICE_FRONTEND]   = 3,
68 	[DVB_DEVICE_DEMUX]      = 4,
69 	[DVB_DEVICE_DVR]        = 5,
70 	[DVB_DEVICE_CA]         = 6,
71 	[DVB_DEVICE_NET]        = 7,
72 	[DVB_DEVICE_OSD]        = 8,
73 };
74 
75 #define nums2minor(num, type, id) \
76 	(((num) << 6) | ((id) << 4) | minor_type[type])
77 
78 #define MAX_DVB_MINORS		(DVB_MAX_ADAPTERS * 64)
79 #endif
80 
81 static struct class *dvb_class;
82 
83 static struct dvb_device *dvb_minors[MAX_DVB_MINORS];
84 static DECLARE_RWSEM(minor_rwsem);
85 
86 static int dvb_device_open(struct inode *inode, struct file *file)
87 {
88 	struct dvb_device *dvbdev;
89 	unsigned int minor = iminor(inode);
90 
91 	if (minor >= MAX_DVB_MINORS)
92 		return -ENODEV;
93 
94 	mutex_lock(&dvbdev_mutex);
95 	down_read(&minor_rwsem);
96 
97 	dvbdev = dvb_minors[minor];
98 
99 	if (dvbdev && dvbdev->fops) {
100 		int err = 0;
101 		const struct file_operations *new_fops;
102 
103 		new_fops = fops_get(dvbdev->fops);
104 		if (!new_fops)
105 			goto fail;
106 		file->private_data = dvb_device_get(dvbdev);
107 		replace_fops(file, new_fops);
108 		if (file->f_op->open)
109 			err = file->f_op->open(inode, file);
110 		up_read(&minor_rwsem);
111 		mutex_unlock(&dvbdev_mutex);
112 		if (err)
113 			dvb_device_put(dvbdev);
114 		return err;
115 	}
116 fail:
117 	up_read(&minor_rwsem);
118 	mutex_unlock(&dvbdev_mutex);
119 	return -ENODEV;
120 }
121 
122 static const struct file_operations dvb_device_fops = {
123 	.owner =	THIS_MODULE,
124 	.open =		dvb_device_open,
125 	.llseek =	noop_llseek,
126 };
127 
128 static struct cdev dvb_device_cdev;
129 
130 int dvb_generic_open(struct inode *inode, struct file *file)
131 {
132 	struct dvb_device *dvbdev = file->private_data;
133 
134 	if (!dvbdev)
135 		return -ENODEV;
136 
137 	if (!dvbdev->users)
138 		return -EBUSY;
139 
140 	if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
141 		if (!dvbdev->readers)
142 			return -EBUSY;
143 		dvbdev->readers--;
144 	} else {
145 		if (!dvbdev->writers)
146 			return -EBUSY;
147 		dvbdev->writers--;
148 	}
149 
150 	dvbdev->users--;
151 	return 0;
152 }
153 EXPORT_SYMBOL(dvb_generic_open);
154 
155 int dvb_generic_release(struct inode *inode, struct file *file)
156 {
157 	struct dvb_device *dvbdev = file->private_data;
158 
159 	if (!dvbdev)
160 		return -ENODEV;
161 
162 	if ((file->f_flags & O_ACCMODE) == O_RDONLY)
163 		dvbdev->readers++;
164 	else
165 		dvbdev->writers++;
166 
167 	dvbdev->users++;
168 
169 	dvb_device_put(dvbdev);
170 
171 	return 0;
172 }
173 EXPORT_SYMBOL(dvb_generic_release);
174 
175 long dvb_generic_ioctl(struct file *file,
176 		       unsigned int cmd, unsigned long arg)
177 {
178 	struct dvb_device *dvbdev = file->private_data;
179 
180 	if (!dvbdev)
181 		return -ENODEV;
182 
183 	if (!dvbdev->kernel_ioctl)
184 		return -EINVAL;
185 
186 	return dvb_usercopy(file, cmd, arg, dvbdev->kernel_ioctl);
187 }
188 EXPORT_SYMBOL(dvb_generic_ioctl);
189 
190 static int dvbdev_get_free_id(struct dvb_adapter *adap, int type)
191 {
192 	u32 id = 0;
193 
194 	while (id < DVB_MAX_IDS) {
195 		struct dvb_device *dev;
196 
197 		list_for_each_entry(dev, &adap->device_list, list_head)
198 			if (dev->type == type && dev->id == id)
199 				goto skip;
200 		return id;
201 skip:
202 		id++;
203 	}
204 	return -ENFILE;
205 }
206 
207 static void dvb_media_device_free(struct dvb_device *dvbdev)
208 {
209 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
210 	if (dvbdev->entity) {
211 		media_device_unregister_entity(dvbdev->entity);
212 		kfree(dvbdev->entity);
213 		kfree(dvbdev->pads);
214 		dvbdev->entity = NULL;
215 		dvbdev->pads = NULL;
216 	}
217 
218 	if (dvbdev->tsout_entity) {
219 		int i;
220 
221 		for (i = 0; i < dvbdev->tsout_num_entities; i++) {
222 			media_device_unregister_entity(&dvbdev->tsout_entity[i]);
223 			kfree(dvbdev->tsout_entity[i].name);
224 		}
225 		kfree(dvbdev->tsout_entity);
226 		kfree(dvbdev->tsout_pads);
227 		dvbdev->tsout_entity = NULL;
228 		dvbdev->tsout_pads = NULL;
229 
230 		dvbdev->tsout_num_entities = 0;
231 	}
232 
233 	if (dvbdev->intf_devnode) {
234 		media_devnode_remove(dvbdev->intf_devnode);
235 		dvbdev->intf_devnode = NULL;
236 	}
237 
238 	if (dvbdev->adapter->conn) {
239 		media_device_unregister_entity(dvbdev->adapter->conn);
240 		kfree(dvbdev->adapter->conn);
241 		dvbdev->adapter->conn = NULL;
242 		kfree(dvbdev->adapter->conn_pads);
243 		dvbdev->adapter->conn_pads = NULL;
244 	}
245 #endif
246 }
247 
248 #if defined(CONFIG_MEDIA_CONTROLLER_DVB)
249 static int dvb_create_tsout_entity(struct dvb_device *dvbdev,
250 				   const char *name, int npads)
251 {
252 	int i;
253 
254 	dvbdev->tsout_pads = kzalloc_objs(*dvbdev->tsout_pads, npads,
255 					  GFP_KERNEL);
256 	if (!dvbdev->tsout_pads)
257 		return -ENOMEM;
258 
259 	dvbdev->tsout_entity = kzalloc_objs(*dvbdev->tsout_entity, npads,
260 					    GFP_KERNEL);
261 	if (!dvbdev->tsout_entity)
262 		return -ENOMEM;
263 
264 	dvbdev->tsout_num_entities = npads;
265 
266 	for (i = 0; i < npads; i++) {
267 		struct media_pad *pads = &dvbdev->tsout_pads[i];
268 		struct media_entity *entity = &dvbdev->tsout_entity[i];
269 		int ret;
270 
271 		entity->name = kasprintf(GFP_KERNEL, "%s #%d", name, i);
272 		if (!entity->name)
273 			return -ENOMEM;
274 
275 		entity->function = MEDIA_ENT_F_IO_DTV;
276 		pads->flags = MEDIA_PAD_FL_SINK;
277 
278 		ret = media_entity_pads_init(entity, 1, pads);
279 		if (ret < 0)
280 			return ret;
281 
282 		ret = media_device_register_entity(dvbdev->adapter->mdev,
283 						   entity);
284 		if (ret < 0)
285 			return ret;
286 	}
287 	return 0;
288 }
289 
290 #define DEMUX_TSOUT	"demux-tsout"
291 #define DVR_TSOUT	"dvr-tsout"
292 
293 static int dvb_create_media_entity(struct dvb_device *dvbdev,
294 				   int type, int demux_sink_pads)
295 {
296 	int i, ret, npads;
297 
298 	switch (type) {
299 	case DVB_DEVICE_FRONTEND:
300 		npads = 2;
301 		break;
302 	case DVB_DEVICE_DVR:
303 		ret = dvb_create_tsout_entity(dvbdev, DVR_TSOUT,
304 					      demux_sink_pads);
305 		return ret;
306 	case DVB_DEVICE_DEMUX:
307 		npads = 1 + demux_sink_pads;
308 		ret = dvb_create_tsout_entity(dvbdev, DEMUX_TSOUT,
309 					      demux_sink_pads);
310 		if (ret < 0)
311 			return ret;
312 		break;
313 	case DVB_DEVICE_CA:
314 		npads = 2;
315 		break;
316 	case DVB_DEVICE_NET:
317 		/*
318 		 * We should be creating entities for the MPE/ULE
319 		 * decapsulation hardware (or software implementation).
320 		 *
321 		 * However, the number of for the MPE/ULE decaps may not be
322 		 * fixed. As we don't have yet dynamic support for PADs at
323 		 * the Media Controller, let's not create the decap
324 		 * entities yet.
325 		 */
326 		return 0;
327 	default:
328 		return 0;
329 	}
330 
331 	dvbdev->entity = kzalloc_obj(*dvbdev->entity, GFP_KERNEL);
332 	if (!dvbdev->entity)
333 		return -ENOMEM;
334 
335 	dvbdev->entity->name = dvbdev->name;
336 
337 	if (npads) {
338 		dvbdev->pads = kzalloc_objs(*dvbdev->pads, npads, GFP_KERNEL);
339 		if (!dvbdev->pads) {
340 			kfree(dvbdev->entity);
341 			dvbdev->entity = NULL;
342 			return -ENOMEM;
343 		}
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 int 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 = NULL;
459 	struct dvbdevfops_node *node = NULL, *new_node = NULL;
460 	struct device *clsdev;
461 	int minor;
462 	int id, ret;
463 
464 	mutex_lock(&dvbdev_register_lock);
465 
466 	id = dvbdev_get_free_id(adap, type);
467 	if (id < 0) {
468 		mutex_unlock(&dvbdev_register_lock);
469 		*pdvbdev = NULL;
470 		pr_err("%s: couldn't find free device id\n", __func__);
471 		return -ENFILE;
472 	}
473 
474 	*pdvbdev = dvbdev = kzalloc_obj(*dvbdev, GFP_KERNEL);
475 	if (!dvbdev) {
476 		mutex_unlock(&dvbdev_register_lock);
477 		return -ENOMEM;
478 	}
479 
480 	/*
481 	 * When a device of the same type is probe()d more than once,
482 	 * the first allocated fops are used. This prevents memory leaks
483 	 * that can occur when the same device is probe()d repeatedly.
484 	 */
485 	list_for_each_entry(node, &dvbdevfops_list, list_head) {
486 		if (node->fops->owner == adap->module &&
487 		    node->type == type && node->template == template) {
488 			dvbdevfops = node->fops;
489 			break;
490 		}
491 	}
492 
493 	if (!dvbdevfops) {
494 		dvbdevfops = kmemdup(template->fops, sizeof(*dvbdevfops), GFP_KERNEL);
495 		if (!dvbdevfops) {
496 			kfree(dvbdev);
497 			*pdvbdev = NULL;
498 			mutex_unlock(&dvbdev_register_lock);
499 			return -ENOMEM;
500 		}
501 
502 		new_node = kzalloc_obj(*new_node, GFP_KERNEL);
503 		if (!new_node) {
504 			kfree(dvbdevfops);
505 			kfree(dvbdev);
506 			*pdvbdev = NULL;
507 			mutex_unlock(&dvbdev_register_lock);
508 			return -ENOMEM;
509 		}
510 
511 		new_node->fops = dvbdevfops;
512 		new_node->type = type;
513 		new_node->template = template;
514 		list_add_tail(&new_node->list_head, &dvbdevfops_list);
515 	}
516 
517 	memcpy(dvbdev, template, sizeof(struct dvb_device));
518 	kref_init(&dvbdev->ref);
519 	dvbdev->type = type;
520 	dvbdev->id = id;
521 	dvbdev->adapter = adap;
522 	dvbdev->priv = priv;
523 	dvbdev->fops = dvbdevfops;
524 	init_waitqueue_head(&dvbdev->wait_queue);
525 	dvbdevfops->owner = adap->module;
526 	list_add_tail(&dvbdev->list_head, &adap->device_list);
527 	down_write(&minor_rwsem);
528 #ifdef CONFIG_DVB_DYNAMIC_MINORS
529 	for (minor = 0; minor < MAX_DVB_MINORS; minor++)
530 		if (!dvb_minors[minor])
531 			break;
532 #else
533 	minor = nums2minor(adap->num, type, id);
534 #endif
535 	if (minor >= MAX_DVB_MINORS) {
536 		if (new_node) {
537 			list_del(&new_node->list_head);
538 			kfree(dvbdevfops);
539 			kfree(new_node);
540 		}
541 		list_del(&dvbdev->list_head);
542 		kfree(dvbdev);
543 		*pdvbdev = NULL;
544 		up_write(&minor_rwsem);
545 		mutex_unlock(&dvbdev_register_lock);
546 		return -EINVAL;
547 	}
548 
549 	dvbdev->minor = minor;
550 	dvb_minors[minor] = dvb_device_get(dvbdev);
551 	up_write(&minor_rwsem);
552 	ret = dvb_register_media_device(dvbdev, type, minor, demux_sink_pads);
553 	if (ret) {
554 		pr_err("%s: dvb_register_media_device failed to create the mediagraph\n",
555 		       __func__);
556 		if (new_node) {
557 			list_del(&new_node->list_head);
558 			kfree(dvbdevfops);
559 			kfree(new_node);
560 		}
561 		dvb_media_device_free(dvbdev);
562 		list_del(&dvbdev->list_head);
563 		kfree(dvbdev);
564 		*pdvbdev = NULL;
565 		mutex_unlock(&dvbdev_register_lock);
566 		return ret;
567 	}
568 
569 	clsdev = device_create(dvb_class, adap->device,
570 			       MKDEV(DVB_MAJOR, minor),
571 			       dvbdev, "dvb%d.%s%d", adap->num, dnames[type], id);
572 	if (IS_ERR(clsdev)) {
573 		pr_err("%s: failed to create device dvb%d.%s%d (%pe)\n",
574 		       __func__, adap->num, dnames[type], id, clsdev);
575 		if (new_node) {
576 			list_del(&new_node->list_head);
577 			kfree(dvbdevfops);
578 			kfree(new_node);
579 		}
580 		dvb_media_device_free(dvbdev);
581 		list_del(&dvbdev->list_head);
582 		kfree(dvbdev);
583 		*pdvbdev = NULL;
584 		mutex_unlock(&dvbdev_register_lock);
585 		return PTR_ERR(clsdev);
586 	}
587 
588 	dprintk("DVB: register adapter%d/%s%d @ minor: %i (0x%02x)\n",
589 		adap->num, dnames[type], id, minor, minor);
590 
591 	mutex_unlock(&dvbdev_register_lock);
592 	return 0;
593 }
594 EXPORT_SYMBOL(dvb_register_device);
595 
596 void dvb_remove_device(struct dvb_device *dvbdev)
597 {
598 	if (!dvbdev)
599 		return;
600 
601 	down_write(&minor_rwsem);
602 	dvb_minors[dvbdev->minor] = NULL;
603 	dvb_device_put(dvbdev);
604 	up_write(&minor_rwsem);
605 
606 	dvb_media_device_free(dvbdev);
607 
608 	device_destroy(dvb_class, MKDEV(DVB_MAJOR, dvbdev->minor));
609 
610 	list_del(&dvbdev->list_head);
611 }
612 EXPORT_SYMBOL(dvb_remove_device);
613 
614 static void dvb_free_device(struct kref *ref)
615 {
616 	struct dvb_device *dvbdev = container_of(ref, struct dvb_device, ref);
617 
618 	kfree(dvbdev);
619 }
620 
621 struct dvb_device *dvb_device_get(struct dvb_device *dvbdev)
622 {
623 	kref_get(&dvbdev->ref);
624 	return dvbdev;
625 }
626 EXPORT_SYMBOL(dvb_device_get);
627 
628 void dvb_device_put(struct dvb_device *dvbdev)
629 {
630 	if (dvbdev)
631 		kref_put(&dvbdev->ref, dvb_free_device);
632 }
633 
634 void dvb_unregister_device(struct dvb_device *dvbdev)
635 {
636 	dvb_remove_device(dvbdev);
637 	dvb_device_put(dvbdev);
638 }
639 EXPORT_SYMBOL(dvb_unregister_device);
640 
641 #ifdef CONFIG_MEDIA_CONTROLLER_DVB
642 
643 static int dvb_create_io_intf_links(struct dvb_adapter *adap,
644 				    struct media_interface *intf,
645 				    char *name)
646 {
647 	struct media_device *mdev = adap->mdev;
648 	struct media_entity *entity;
649 	struct media_link *link;
650 
651 	media_device_for_each_entity(entity, mdev) {
652 		if (entity->function == MEDIA_ENT_F_IO_DTV) {
653 			if (strncmp(entity->name, name, strlen(name)))
654 				continue;
655 			link = media_create_intf_link(entity, intf,
656 						      MEDIA_LNK_FL_ENABLED |
657 						      MEDIA_LNK_FL_IMMUTABLE);
658 			if (!link)
659 				return -ENOMEM;
660 		}
661 	}
662 	return 0;
663 }
664 
665 int dvb_create_media_graph(struct dvb_adapter *adap,
666 			   bool create_rf_connector)
667 {
668 	struct media_device *mdev = adap->mdev;
669 	struct media_entity *entity, *tuner = NULL, *demod = NULL, *conn;
670 	struct media_entity *demux = NULL, *ca = NULL;
671 	struct media_link *link;
672 	struct media_interface *intf;
673 	unsigned int demux_pad = 0;
674 	unsigned int dvr_pad = 0;
675 	unsigned int ntuner = 0, ndemod = 0;
676 	int ret, pad_source, pad_sink;
677 	static const char *connector_name = "Television";
678 
679 	if (!mdev)
680 		return 0;
681 
682 	media_device_for_each_entity(entity, mdev) {
683 		switch (entity->function) {
684 		case MEDIA_ENT_F_TUNER:
685 			tuner = entity;
686 			ntuner++;
687 			break;
688 		case MEDIA_ENT_F_DTV_DEMOD:
689 			demod = entity;
690 			ndemod++;
691 			break;
692 		case MEDIA_ENT_F_TS_DEMUX:
693 			demux = entity;
694 			break;
695 		case MEDIA_ENT_F_DTV_CA:
696 			ca = entity;
697 			break;
698 		}
699 	}
700 
701 	/*
702 	 * Prepare to signalize to media_create_pad_links() that multiple
703 	 * entities of the same type exists and a 1:n or n:1 links need to be
704 	 * created.
705 	 * NOTE: if both tuner and demod have multiple instances, it is up
706 	 * to the caller driver to create such links.
707 	 */
708 	if (ntuner > 1)
709 		tuner = NULL;
710 	if (ndemod > 1)
711 		demod = NULL;
712 
713 	if (create_rf_connector) {
714 		conn = kzalloc_obj(*conn, GFP_KERNEL);
715 		if (!conn)
716 			return -ENOMEM;
717 		adap->conn = conn;
718 
719 		adap->conn_pads = kzalloc_obj(*adap->conn_pads, GFP_KERNEL);
720 		if (!adap->conn_pads)
721 			return -ENOMEM;
722 
723 		conn->flags = MEDIA_ENT_FL_CONNECTOR;
724 		conn->function = MEDIA_ENT_F_CONN_RF;
725 		conn->name = connector_name;
726 		adap->conn_pads->flags = MEDIA_PAD_FL_SOURCE;
727 
728 		ret = media_entity_pads_init(conn, 1, adap->conn_pads);
729 		if (ret)
730 			return ret;
731 
732 		ret = media_device_register_entity(mdev, conn);
733 		if (ret)
734 			return ret;
735 
736 		if (!ntuner) {
737 			ret = media_create_pad_links(mdev,
738 						     MEDIA_ENT_F_CONN_RF,
739 						     conn, 0,
740 						     MEDIA_ENT_F_DTV_DEMOD,
741 						     demod, 0,
742 						     MEDIA_LNK_FL_ENABLED,
743 						     false);
744 		} else {
745 			pad_sink = media_get_pad_index(tuner, MEDIA_PAD_FL_SINK,
746 						       PAD_SIGNAL_ANALOG);
747 			if (pad_sink < 0)
748 				return -EINVAL;
749 			ret = media_create_pad_links(mdev,
750 						     MEDIA_ENT_F_CONN_RF,
751 						     conn, 0,
752 						     MEDIA_ENT_F_TUNER,
753 						     tuner, pad_sink,
754 						     MEDIA_LNK_FL_ENABLED,
755 						     false);
756 		}
757 		if (ret)
758 			return ret;
759 	}
760 
761 	if (ntuner && ndemod) {
762 		/* NOTE: first found tuner source pad presumed correct */
763 		pad_source = media_get_pad_index(tuner, MEDIA_PAD_FL_SOURCE,
764 						 PAD_SIGNAL_ANALOG);
765 		if (pad_source < 0)
766 			return -EINVAL;
767 		ret = media_create_pad_links(mdev,
768 					     MEDIA_ENT_F_TUNER,
769 					     tuner, pad_source,
770 					     MEDIA_ENT_F_DTV_DEMOD,
771 					     demod, 0, MEDIA_LNK_FL_ENABLED,
772 					     false);
773 		if (ret)
774 			return ret;
775 	}
776 
777 	if (ndemod && demux) {
778 		ret = media_create_pad_links(mdev,
779 					     MEDIA_ENT_F_DTV_DEMOD,
780 					     demod, 1,
781 					     MEDIA_ENT_F_TS_DEMUX,
782 					     demux, 0, MEDIA_LNK_FL_ENABLED,
783 					     false);
784 		if (ret)
785 			return ret;
786 	}
787 	if (demux && ca) {
788 		ret = media_create_pad_link(demux, 1, ca,
789 					    0, MEDIA_LNK_FL_ENABLED);
790 		if (ret)
791 			return ret;
792 	}
793 
794 	/* Create demux links for each ringbuffer/pad */
795 	if (demux) {
796 		media_device_for_each_entity(entity, mdev) {
797 			if (entity->function == MEDIA_ENT_F_IO_DTV) {
798 				if (!strncmp(entity->name, DVR_TSOUT,
799 					     strlen(DVR_TSOUT))) {
800 					ret = media_create_pad_link(demux,
801 								    ++dvr_pad,
802 								    entity, 0, 0);
803 					if (ret)
804 						return ret;
805 				}
806 				if (!strncmp(entity->name, DEMUX_TSOUT,
807 					     strlen(DEMUX_TSOUT))) {
808 					ret = media_create_pad_link(demux,
809 								    ++demux_pad,
810 								    entity, 0, 0);
811 					if (ret)
812 						return ret;
813 				}
814 			}
815 		}
816 	}
817 
818 	/* Create interface links for FE->tuner, DVR->demux and CA->ca */
819 	media_device_for_each_intf(intf, mdev) {
820 		if (intf->type == MEDIA_INTF_T_DVB_CA && ca) {
821 			link = media_create_intf_link(ca, intf,
822 						      MEDIA_LNK_FL_ENABLED |
823 						      MEDIA_LNK_FL_IMMUTABLE);
824 			if (!link)
825 				return -ENOMEM;
826 		}
827 
828 		if (intf->type == MEDIA_INTF_T_DVB_FE && tuner) {
829 			link = media_create_intf_link(tuner, intf,
830 						      MEDIA_LNK_FL_ENABLED |
831 						      MEDIA_LNK_FL_IMMUTABLE);
832 			if (!link)
833 				return -ENOMEM;
834 		}
835 #if 0
836 		/*
837 		 * Indirect link - let's not create yet, as we don't know how
838 		 *		   to handle indirect links, nor if this will
839 		 *		   actually be needed.
840 		 */
841 		if (intf->type == MEDIA_INTF_T_DVB_DVR && demux) {
842 			link = media_create_intf_link(demux, intf,
843 						      MEDIA_LNK_FL_ENABLED |
844 						      MEDIA_LNK_FL_IMMUTABLE);
845 			if (!link)
846 				return -ENOMEM;
847 		}
848 #endif
849 		if (intf->type == MEDIA_INTF_T_DVB_DVR) {
850 			ret = dvb_create_io_intf_links(adap, intf, DVR_TSOUT);
851 			if (ret)
852 				return ret;
853 		}
854 		if (intf->type == MEDIA_INTF_T_DVB_DEMUX) {
855 			ret = dvb_create_io_intf_links(adap, intf, DEMUX_TSOUT);
856 			if (ret)
857 				return ret;
858 		}
859 	}
860 	return 0;
861 }
862 EXPORT_SYMBOL_GPL(dvb_create_media_graph);
863 #endif
864 
865 static int dvbdev_check_free_adapter_num(int num)
866 {
867 	struct list_head *entry;
868 
869 	list_for_each(entry, &dvb_adapter_list) {
870 		struct dvb_adapter *adap;
871 
872 		adap = list_entry(entry, struct dvb_adapter, list_head);
873 		if (adap->num == num)
874 			return 0;
875 	}
876 	return 1;
877 }
878 
879 static int dvbdev_get_free_adapter_num(void)
880 {
881 	int num = 0;
882 
883 	while (num < DVB_MAX_ADAPTERS) {
884 		if (dvbdev_check_free_adapter_num(num))
885 			return num;
886 		num++;
887 	}
888 
889 	return -ENFILE;
890 }
891 
892 int dvb_register_adapter(struct dvb_adapter *adap, const char *name,
893 			 struct module *module, struct device *device,
894 			 short *adapter_nums)
895 {
896 	int i, num;
897 
898 	mutex_lock(&dvbdev_register_lock);
899 
900 	for (i = 0; i < DVB_MAX_ADAPTERS; ++i) {
901 		num = adapter_nums[i];
902 		if (num >= 0  &&  num < DVB_MAX_ADAPTERS) {
903 		/* use the one the driver asked for */
904 			if (dvbdev_check_free_adapter_num(num))
905 				break;
906 		} else {
907 			num = dvbdev_get_free_adapter_num();
908 			break;
909 		}
910 		num = -1;
911 	}
912 
913 	if (num < 0) {
914 		mutex_unlock(&dvbdev_register_lock);
915 		return -ENFILE;
916 	}
917 
918 	memset(adap, 0, sizeof(struct dvb_adapter));
919 	INIT_LIST_HEAD(&adap->device_list);
920 
921 	pr_info("DVB: registering new adapter (%s)\n", name);
922 
923 	adap->num = num;
924 	adap->name = name;
925 	adap->module = module;
926 	adap->device = device;
927 	adap->mfe_shared = 0;
928 	adap->mfe_dvbdev = NULL;
929 	mutex_init(&adap->mfe_lock);
930 
931 #ifdef CONFIG_MEDIA_CONTROLLER_DVB
932 	mutex_init(&adap->mdev_lock);
933 #endif
934 
935 	list_add_tail(&adap->list_head, &dvb_adapter_list);
936 
937 	mutex_unlock(&dvbdev_register_lock);
938 
939 	return num;
940 }
941 EXPORT_SYMBOL(dvb_register_adapter);
942 
943 int dvb_unregister_adapter(struct dvb_adapter *adap)
944 {
945 	mutex_lock(&dvbdev_register_lock);
946 	list_del(&adap->list_head);
947 	mutex_unlock(&dvbdev_register_lock);
948 	return 0;
949 }
950 EXPORT_SYMBOL(dvb_unregister_adapter);
951 
952 /*
953  * if the miracle happens and "generic_usercopy()" is included into
954  * the kernel, then this can vanish. please don't make the mistake and
955  * define this as video_usercopy(). this will introduce a dependency
956  * to the v4l "videodev.o" module, which is unnecessary for some
957  * cards (ie. the budget dvb-cards don't need the v4l module...)
958  */
959 int dvb_usercopy(struct file *file,
960 		 unsigned int cmd, unsigned long arg,
961 		 int (*func)(struct file *file,
962 			     unsigned int cmd, void *arg))
963 {
964 	char    sbuf[128] = {};
965 	void    *mbuf = NULL;
966 	void    *parg = NULL;
967 	int     err  = -EINVAL;
968 
969 	/*  Copy arguments into temp kernel buffer  */
970 	switch (_IOC_DIR(cmd)) {
971 	case _IOC_NONE:
972 		/*
973 		 * For this command, the pointer is actually an integer
974 		 * argument.
975 		 */
976 		parg = (void *)arg;
977 		break;
978 	case _IOC_READ: /* some v4l ioctls are marked wrong ... */
979 	case _IOC_WRITE:
980 	case (_IOC_WRITE | _IOC_READ):
981 		if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
982 			parg = sbuf;
983 		} else {
984 			/* too big to allocate from stack */
985 			mbuf = kmalloc(_IOC_SIZE(cmd), GFP_KERNEL);
986 			if (!mbuf)
987 				return -ENOMEM;
988 			parg = mbuf;
989 		}
990 
991 		err = -EFAULT;
992 		if (copy_from_user(parg, (void __user *)arg, _IOC_SIZE(cmd)))
993 			goto out;
994 		break;
995 	}
996 
997 	/* call driver */
998 	err = func(file, cmd, parg);
999 	if (err == -ENOIOCTLCMD)
1000 		err = -ENOTTY;
1001 
1002 	if (err < 0)
1003 		goto out;
1004 
1005 	/*  Copy results into user buffer  */
1006 	switch (_IOC_DIR(cmd)) {
1007 	case _IOC_READ:
1008 	case (_IOC_WRITE | _IOC_READ):
1009 		if (copy_to_user((void __user *)arg, parg, _IOC_SIZE(cmd)))
1010 			err = -EFAULT;
1011 		break;
1012 	}
1013 
1014 out:
1015 	kfree(mbuf);
1016 	return err;
1017 }
1018 
1019 #if IS_ENABLED(CONFIG_I2C)
1020 struct i2c_client *dvb_module_probe(const char *module_name,
1021 				    const char *name,
1022 				    struct i2c_adapter *adap,
1023 				    unsigned char addr,
1024 				    void *platform_data)
1025 {
1026 	struct i2c_client *client;
1027 	struct i2c_board_info *board_info;
1028 
1029 	board_info = kzalloc_obj(*board_info, GFP_KERNEL);
1030 	if (!board_info)
1031 		return NULL;
1032 
1033 	if (name)
1034 		strscpy(board_info->type, name, I2C_NAME_SIZE);
1035 	else
1036 		strscpy(board_info->type, module_name, I2C_NAME_SIZE);
1037 
1038 	board_info->addr = addr;
1039 	board_info->platform_data = platform_data;
1040 	request_module(module_name);
1041 	client = i2c_new_client_device(adap, board_info);
1042 	if (!i2c_client_has_driver(client)) {
1043 		kfree(board_info);
1044 		return NULL;
1045 	}
1046 
1047 	if (!try_module_get(client->dev.driver->owner)) {
1048 		i2c_unregister_device(client);
1049 		client = NULL;
1050 	}
1051 
1052 	kfree(board_info);
1053 	return client;
1054 }
1055 EXPORT_SYMBOL_GPL(dvb_module_probe);
1056 
1057 void dvb_module_release(struct i2c_client *client)
1058 {
1059 	if (!client)
1060 		return;
1061 
1062 	module_put(client->dev.driver->owner);
1063 	i2c_unregister_device(client);
1064 }
1065 EXPORT_SYMBOL_GPL(dvb_module_release);
1066 #endif
1067 
1068 static int dvb_uevent(const struct device *dev, struct kobj_uevent_env *env)
1069 {
1070 	const struct dvb_device *dvbdev = dev_get_drvdata(dev);
1071 
1072 	add_uevent_var(env, "DVB_ADAPTER_NUM=%d", dvbdev->adapter->num);
1073 	add_uevent_var(env, "DVB_DEVICE_TYPE=%s", dnames[dvbdev->type]);
1074 	add_uevent_var(env, "DVB_DEVICE_NUM=%d", dvbdev->id);
1075 	return 0;
1076 }
1077 
1078 static char *dvb_devnode(const struct device *dev, umode_t *mode)
1079 {
1080 	const struct dvb_device *dvbdev = dev_get_drvdata(dev);
1081 
1082 	return kasprintf(GFP_KERNEL, "dvb/adapter%d/%s%d",
1083 		dvbdev->adapter->num, dnames[dvbdev->type], dvbdev->id);
1084 }
1085 
1086 static int __init init_dvbdev(void)
1087 {
1088 	int retval;
1089 	dev_t dev = MKDEV(DVB_MAJOR, 0);
1090 
1091 	retval = register_chrdev_region(dev, MAX_DVB_MINORS, "DVB");
1092 	if (retval != 0) {
1093 		pr_err("dvb-core: unable to get major %d\n", DVB_MAJOR);
1094 		return retval;
1095 	}
1096 
1097 	cdev_init(&dvb_device_cdev, &dvb_device_fops);
1098 	retval = cdev_add(&dvb_device_cdev, dev, MAX_DVB_MINORS);
1099 	if (retval != 0) {
1100 		pr_err("dvb-core: unable register character device\n");
1101 		goto error;
1102 	}
1103 
1104 	dvb_class = class_create("dvb");
1105 	if (IS_ERR(dvb_class)) {
1106 		retval = PTR_ERR(dvb_class);
1107 		goto error;
1108 	}
1109 	dvb_class->dev_uevent = dvb_uevent;
1110 	dvb_class->devnode = dvb_devnode;
1111 	return 0;
1112 
1113 error:
1114 	cdev_del(&dvb_device_cdev);
1115 	unregister_chrdev_region(dev, MAX_DVB_MINORS);
1116 	return retval;
1117 }
1118 
1119 static void __exit exit_dvbdev(void)
1120 {
1121 	struct dvbdevfops_node *node, *next;
1122 
1123 	class_destroy(dvb_class);
1124 	cdev_del(&dvb_device_cdev);
1125 	unregister_chrdev_region(MKDEV(DVB_MAJOR, 0), MAX_DVB_MINORS);
1126 
1127 	list_for_each_entry_safe(node, next, &dvbdevfops_list, list_head) {
1128 		list_del(&node->list_head);
1129 		kfree(node->fops);
1130 		kfree(node);
1131 	}
1132 }
1133 
1134 subsys_initcall(init_dvbdev);
1135 module_exit(exit_dvbdev);
1136 
1137 MODULE_DESCRIPTION("DVB Core Driver");
1138 MODULE_AUTHOR("Marcus Metzler, Ralph Metzler, Holger Waechtler");
1139 MODULE_LICENSE("GPL");
1140