1  // SPDX-License-Identifier: GPL-2.0-only
2  /*
3   * Media device
4   *
5   * Copyright (C) 2010 Nokia Corporation
6   *
7   * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
8   *	     Sakari Ailus <sakari.ailus@iki.fi>
9   */
10  
11  #include <linux/compat.h>
12  #include <linux/export.h>
13  #include <linux/idr.h>
14  #include <linux/ioctl.h>
15  #include <linux/media.h>
16  #include <linux/slab.h>
17  #include <linux/types.h>
18  #include <linux/pci.h>
19  #include <linux/usb.h>
20  #include <linux/version.h>
21  
22  #include <media/media-device.h>
23  #include <media/media-devnode.h>
24  #include <media/media-entity.h>
25  #include <media/media-request.h>
26  
27  #ifdef CONFIG_MEDIA_CONTROLLER
28  
29  /*
30   * Legacy defines from linux/media.h. This is the only place we need this
31   * so we just define it here. The media.h header doesn't expose it to the
32   * kernel to prevent it from being used by drivers, but here (and only here!)
33   * we need it to handle the legacy behavior.
34   */
35  #define MEDIA_ENT_SUBTYPE_MASK			0x0000ffff
36  #define MEDIA_ENT_T_DEVNODE_UNKNOWN		(MEDIA_ENT_F_OLD_BASE | \
37  						 MEDIA_ENT_SUBTYPE_MASK)
38  
39  /* -----------------------------------------------------------------------------
40   * Userspace API
41   */
42  
media_get_uptr(__u64 arg)43  static inline void __user *media_get_uptr(__u64 arg)
44  {
45  	return (void __user *)(uintptr_t)arg;
46  }
47  
media_device_open(struct file * filp)48  static int media_device_open(struct file *filp)
49  {
50  	return 0;
51  }
52  
media_device_close(struct file * filp)53  static int media_device_close(struct file *filp)
54  {
55  	return 0;
56  }
57  
media_device_get_info(struct media_device * dev,void * arg)58  static long media_device_get_info(struct media_device *dev, void *arg)
59  {
60  	struct media_device_info *info = arg;
61  
62  	memset(info, 0, sizeof(*info));
63  
64  	if (dev->driver_name[0])
65  		strscpy(info->driver, dev->driver_name, sizeof(info->driver));
66  	else
67  		strscpy(info->driver, dev->dev->driver->name,
68  			sizeof(info->driver));
69  
70  	strscpy(info->model, dev->model, sizeof(info->model));
71  	strscpy(info->serial, dev->serial, sizeof(info->serial));
72  	strscpy(info->bus_info, dev->bus_info, sizeof(info->bus_info));
73  
74  	info->media_version = LINUX_VERSION_CODE;
75  	info->driver_version = info->media_version;
76  	info->hw_revision = dev->hw_revision;
77  
78  	return 0;
79  }
80  
find_entity(struct media_device * mdev,u32 id)81  static struct media_entity *find_entity(struct media_device *mdev, u32 id)
82  {
83  	struct media_entity *entity;
84  	int next = id & MEDIA_ENT_ID_FLAG_NEXT;
85  
86  	id &= ~MEDIA_ENT_ID_FLAG_NEXT;
87  
88  	media_device_for_each_entity(entity, mdev) {
89  		if (((media_entity_id(entity) == id) && !next) ||
90  		    ((media_entity_id(entity) > id) && next)) {
91  			return entity;
92  		}
93  	}
94  
95  	return NULL;
96  }
97  
media_device_enum_entities(struct media_device * mdev,void * arg)98  static long media_device_enum_entities(struct media_device *mdev, void *arg)
99  {
100  	struct media_entity_desc *entd = arg;
101  	struct media_entity *ent;
102  
103  	ent = find_entity(mdev, entd->id);
104  	if (ent == NULL)
105  		return -EINVAL;
106  
107  	memset(entd, 0, sizeof(*entd));
108  
109  	entd->id = media_entity_id(ent);
110  	if (ent->name)
111  		strscpy(entd->name, ent->name, sizeof(entd->name));
112  	entd->type = ent->function;
113  	entd->revision = 0;		/* Unused */
114  	entd->flags = ent->flags;
115  	entd->group_id = 0;		/* Unused */
116  	entd->pads = ent->num_pads;
117  	entd->links = ent->num_links - ent->num_backlinks;
118  
119  	/*
120  	 * Workaround for a bug at media-ctl <= v1.10 that makes it to
121  	 * do the wrong thing if the entity function doesn't belong to
122  	 * either MEDIA_ENT_F_OLD_BASE or MEDIA_ENT_F_OLD_SUBDEV_BASE
123  	 * Ranges.
124  	 *
125  	 * Non-subdevices are expected to be at the MEDIA_ENT_F_OLD_BASE,
126  	 * or, otherwise, will be silently ignored by media-ctl when
127  	 * printing the graphviz diagram. So, map them into the devnode
128  	 * old range.
129  	 */
130  	if (ent->function < MEDIA_ENT_F_OLD_BASE ||
131  	    ent->function > MEDIA_ENT_F_TUNER) {
132  		if (is_media_entity_v4l2_subdev(ent))
133  			entd->type = MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN;
134  		else if (ent->function != MEDIA_ENT_F_IO_V4L)
135  			entd->type = MEDIA_ENT_T_DEVNODE_UNKNOWN;
136  	}
137  
138  	memcpy(&entd->raw, &ent->info, sizeof(ent->info));
139  
140  	return 0;
141  }
142  
media_device_kpad_to_upad(const struct media_pad * kpad,struct media_pad_desc * upad)143  static void media_device_kpad_to_upad(const struct media_pad *kpad,
144  				      struct media_pad_desc *upad)
145  {
146  	upad->entity = media_entity_id(kpad->entity);
147  	upad->index = kpad->index;
148  	upad->flags = kpad->flags;
149  }
150  
media_device_enum_links(struct media_device * mdev,void * arg)151  static long media_device_enum_links(struct media_device *mdev, void *arg)
152  {
153  	struct media_links_enum *links = arg;
154  	struct media_entity *entity;
155  
156  	entity = find_entity(mdev, links->entity);
157  	if (entity == NULL)
158  		return -EINVAL;
159  
160  	if (links->pads) {
161  		unsigned int p;
162  
163  		for (p = 0; p < entity->num_pads; p++) {
164  			struct media_pad_desc pad;
165  
166  			memset(&pad, 0, sizeof(pad));
167  			media_device_kpad_to_upad(&entity->pads[p], &pad);
168  			if (copy_to_user(&links->pads[p], &pad, sizeof(pad)))
169  				return -EFAULT;
170  		}
171  	}
172  
173  	if (links->links) {
174  		struct media_link *link;
175  		struct media_link_desc __user *ulink_desc = links->links;
176  
177  		list_for_each_entry(link, &entity->links, list) {
178  			struct media_link_desc klink_desc;
179  
180  			/* Ignore backlinks. */
181  			if (link->source->entity != entity)
182  				continue;
183  			memset(&klink_desc, 0, sizeof(klink_desc));
184  			media_device_kpad_to_upad(link->source,
185  						  &klink_desc.source);
186  			media_device_kpad_to_upad(link->sink,
187  						  &klink_desc.sink);
188  			klink_desc.flags = link->flags;
189  			if (copy_to_user(ulink_desc, &klink_desc,
190  					 sizeof(*ulink_desc)))
191  				return -EFAULT;
192  			ulink_desc++;
193  		}
194  	}
195  	memset(links->reserved, 0, sizeof(links->reserved));
196  
197  	return 0;
198  }
199  
media_device_setup_link(struct media_device * mdev,void * arg)200  static long media_device_setup_link(struct media_device *mdev, void *arg)
201  {
202  	struct media_link_desc *linkd = arg;
203  	struct media_link *link = NULL;
204  	struct media_entity *source;
205  	struct media_entity *sink;
206  
207  	/* Find the source and sink entities and link.
208  	 */
209  	source = find_entity(mdev, linkd->source.entity);
210  	sink = find_entity(mdev, linkd->sink.entity);
211  
212  	if (source == NULL || sink == NULL)
213  		return -EINVAL;
214  
215  	if (linkd->source.index >= source->num_pads ||
216  	    linkd->sink.index >= sink->num_pads)
217  		return -EINVAL;
218  
219  	link = media_entity_find_link(&source->pads[linkd->source.index],
220  				      &sink->pads[linkd->sink.index]);
221  	if (link == NULL)
222  		return -EINVAL;
223  
224  	memset(linkd->reserved, 0, sizeof(linkd->reserved));
225  
226  	/* Setup the link on both entities. */
227  	return __media_entity_setup_link(link, linkd->flags);
228  }
229  
media_device_get_topology(struct media_device * mdev,void * arg)230  static long media_device_get_topology(struct media_device *mdev, void *arg)
231  {
232  	struct media_v2_topology *topo = arg;
233  	struct media_entity *entity;
234  	struct media_interface *intf;
235  	struct media_pad *pad;
236  	struct media_link *link;
237  	struct media_v2_entity kentity, __user *uentity;
238  	struct media_v2_interface kintf, __user *uintf;
239  	struct media_v2_pad kpad, __user *upad;
240  	struct media_v2_link klink, __user *ulink;
241  	unsigned int i;
242  	int ret = 0;
243  
244  	topo->topology_version = mdev->topology_version;
245  
246  	/* Get entities and number of entities */
247  	i = 0;
248  	uentity = media_get_uptr(topo->ptr_entities);
249  	media_device_for_each_entity(entity, mdev) {
250  		i++;
251  		if (ret || !uentity)
252  			continue;
253  
254  		if (i > topo->num_entities) {
255  			ret = -ENOSPC;
256  			continue;
257  		}
258  
259  		/* Copy fields to userspace struct if not error */
260  		memset(&kentity, 0, sizeof(kentity));
261  		kentity.id = entity->graph_obj.id;
262  		kentity.function = entity->function;
263  		kentity.flags = entity->flags;
264  		strscpy(kentity.name, entity->name,
265  			sizeof(kentity.name));
266  
267  		if (copy_to_user(uentity, &kentity, sizeof(kentity)))
268  			ret = -EFAULT;
269  		uentity++;
270  	}
271  	topo->num_entities = i;
272  	topo->reserved1 = 0;
273  
274  	/* Get interfaces and number of interfaces */
275  	i = 0;
276  	uintf = media_get_uptr(topo->ptr_interfaces);
277  	media_device_for_each_intf(intf, mdev) {
278  		i++;
279  		if (ret || !uintf)
280  			continue;
281  
282  		if (i > topo->num_interfaces) {
283  			ret = -ENOSPC;
284  			continue;
285  		}
286  
287  		memset(&kintf, 0, sizeof(kintf));
288  
289  		/* Copy intf fields to userspace struct */
290  		kintf.id = intf->graph_obj.id;
291  		kintf.intf_type = intf->type;
292  		kintf.flags = intf->flags;
293  
294  		if (media_type(&intf->graph_obj) == MEDIA_GRAPH_INTF_DEVNODE) {
295  			struct media_intf_devnode *devnode;
296  
297  			devnode = intf_to_devnode(intf);
298  
299  			kintf.devnode.major = devnode->major;
300  			kintf.devnode.minor = devnode->minor;
301  		}
302  
303  		if (copy_to_user(uintf, &kintf, sizeof(kintf)))
304  			ret = -EFAULT;
305  		uintf++;
306  	}
307  	topo->num_interfaces = i;
308  	topo->reserved2 = 0;
309  
310  	/* Get pads and number of pads */
311  	i = 0;
312  	upad = media_get_uptr(topo->ptr_pads);
313  	media_device_for_each_pad(pad, mdev) {
314  		i++;
315  		if (ret || !upad)
316  			continue;
317  
318  		if (i > topo->num_pads) {
319  			ret = -ENOSPC;
320  			continue;
321  		}
322  
323  		memset(&kpad, 0, sizeof(kpad));
324  
325  		/* Copy pad fields to userspace struct */
326  		kpad.id = pad->graph_obj.id;
327  		kpad.entity_id = pad->entity->graph_obj.id;
328  		kpad.flags = pad->flags;
329  		kpad.index = pad->index;
330  
331  		if (copy_to_user(upad, &kpad, sizeof(kpad)))
332  			ret = -EFAULT;
333  		upad++;
334  	}
335  	topo->num_pads = i;
336  	topo->reserved3 = 0;
337  
338  	/* Get links and number of links */
339  	i = 0;
340  	ulink = media_get_uptr(topo->ptr_links);
341  	media_device_for_each_link(link, mdev) {
342  		if (link->is_backlink)
343  			continue;
344  
345  		i++;
346  
347  		if (ret || !ulink)
348  			continue;
349  
350  		if (i > topo->num_links) {
351  			ret = -ENOSPC;
352  			continue;
353  		}
354  
355  		memset(&klink, 0, sizeof(klink));
356  
357  		/* Copy link fields to userspace struct */
358  		klink.id = link->graph_obj.id;
359  		klink.source_id = link->gobj0->id;
360  		klink.sink_id = link->gobj1->id;
361  		klink.flags = link->flags;
362  
363  		if (copy_to_user(ulink, &klink, sizeof(klink)))
364  			ret = -EFAULT;
365  		ulink++;
366  	}
367  	topo->num_links = i;
368  	topo->reserved4 = 0;
369  
370  	return ret;
371  }
372  
media_device_request_alloc(struct media_device * mdev,void * arg)373  static long media_device_request_alloc(struct media_device *mdev, void *arg)
374  {
375  	int *alloc_fd = arg;
376  
377  	if (!mdev->ops || !mdev->ops->req_validate || !mdev->ops->req_queue)
378  		return -ENOTTY;
379  
380  	return media_request_alloc(mdev, alloc_fd);
381  }
382  
copy_arg_from_user(void * karg,void __user * uarg,unsigned int cmd)383  static long copy_arg_from_user(void *karg, void __user *uarg, unsigned int cmd)
384  {
385  	if ((_IOC_DIR(cmd) & _IOC_WRITE) &&
386  	    copy_from_user(karg, uarg, _IOC_SIZE(cmd)))
387  		return -EFAULT;
388  
389  	return 0;
390  }
391  
copy_arg_to_user(void __user * uarg,void * karg,unsigned int cmd)392  static long copy_arg_to_user(void __user *uarg, void *karg, unsigned int cmd)
393  {
394  	if ((_IOC_DIR(cmd) & _IOC_READ) &&
395  	    copy_to_user(uarg, karg, _IOC_SIZE(cmd)))
396  		return -EFAULT;
397  
398  	return 0;
399  }
400  
401  /* Do acquire the graph mutex */
402  #define MEDIA_IOC_FL_GRAPH_MUTEX	BIT(0)
403  
404  #define MEDIA_IOC_ARG(__cmd, func, fl, from_user, to_user)		\
405  	[_IOC_NR(MEDIA_IOC_##__cmd)] = {				\
406  		.cmd = MEDIA_IOC_##__cmd,				\
407  		.fn = func,						\
408  		.flags = fl,						\
409  		.arg_from_user = from_user,				\
410  		.arg_to_user = to_user,					\
411  	}
412  
413  #define MEDIA_IOC(__cmd, func, fl)					\
414  	MEDIA_IOC_ARG(__cmd, func, fl, copy_arg_from_user, copy_arg_to_user)
415  
416  /* the table is indexed by _IOC_NR(cmd) */
417  struct media_ioctl_info {
418  	unsigned int cmd;
419  	unsigned short flags;
420  	long (*fn)(struct media_device *dev, void *arg);
421  	long (*arg_from_user)(void *karg, void __user *uarg, unsigned int cmd);
422  	long (*arg_to_user)(void __user *uarg, void *karg, unsigned int cmd);
423  };
424  
425  static const struct media_ioctl_info ioctl_info[] = {
426  	MEDIA_IOC(DEVICE_INFO, media_device_get_info, MEDIA_IOC_FL_GRAPH_MUTEX),
427  	MEDIA_IOC(ENUM_ENTITIES, media_device_enum_entities, MEDIA_IOC_FL_GRAPH_MUTEX),
428  	MEDIA_IOC(ENUM_LINKS, media_device_enum_links, MEDIA_IOC_FL_GRAPH_MUTEX),
429  	MEDIA_IOC(SETUP_LINK, media_device_setup_link, MEDIA_IOC_FL_GRAPH_MUTEX),
430  	MEDIA_IOC(G_TOPOLOGY, media_device_get_topology, MEDIA_IOC_FL_GRAPH_MUTEX),
431  	MEDIA_IOC(REQUEST_ALLOC, media_device_request_alloc, 0),
432  };
433  
media_device_ioctl(struct file * filp,unsigned int cmd,unsigned long __arg)434  static long media_device_ioctl(struct file *filp, unsigned int cmd,
435  			       unsigned long __arg)
436  {
437  	struct media_devnode *devnode = media_devnode_data(filp);
438  	struct media_device *dev = devnode->media_dev;
439  	const struct media_ioctl_info *info;
440  	void __user *arg = (void __user *)__arg;
441  	char __karg[256], *karg = __karg;
442  	long ret;
443  
444  	if (_IOC_NR(cmd) >= ARRAY_SIZE(ioctl_info)
445  	    || ioctl_info[_IOC_NR(cmd)].cmd != cmd)
446  		return -ENOIOCTLCMD;
447  
448  	info = &ioctl_info[_IOC_NR(cmd)];
449  
450  	if (_IOC_SIZE(info->cmd) > sizeof(__karg)) {
451  		karg = kmalloc(_IOC_SIZE(info->cmd), GFP_KERNEL);
452  		if (!karg)
453  			return -ENOMEM;
454  	}
455  
456  	if (info->arg_from_user) {
457  		ret = info->arg_from_user(karg, arg, cmd);
458  		if (ret)
459  			goto out_free;
460  	}
461  
462  	if (info->flags & MEDIA_IOC_FL_GRAPH_MUTEX)
463  		mutex_lock(&dev->graph_mutex);
464  
465  	ret = info->fn(dev, karg);
466  
467  	if (info->flags & MEDIA_IOC_FL_GRAPH_MUTEX)
468  		mutex_unlock(&dev->graph_mutex);
469  
470  	if (!ret && info->arg_to_user)
471  		ret = info->arg_to_user(arg, karg, cmd);
472  
473  out_free:
474  	if (karg != __karg)
475  		kfree(karg);
476  
477  	return ret;
478  }
479  
480  #ifdef CONFIG_COMPAT
481  
482  struct media_links_enum32 {
483  	__u32 entity;
484  	compat_uptr_t pads; /* struct media_pad_desc * */
485  	compat_uptr_t links; /* struct media_link_desc * */
486  	__u32 reserved[4];
487  };
488  
media_device_enum_links32(struct media_device * mdev,struct media_links_enum32 __user * ulinks)489  static long media_device_enum_links32(struct media_device *mdev,
490  				      struct media_links_enum32 __user *ulinks)
491  {
492  	struct media_links_enum links;
493  	compat_uptr_t pads_ptr, links_ptr;
494  	int ret;
495  
496  	memset(&links, 0, sizeof(links));
497  
498  	if (get_user(links.entity, &ulinks->entity)
499  	    || get_user(pads_ptr, &ulinks->pads)
500  	    || get_user(links_ptr, &ulinks->links))
501  		return -EFAULT;
502  
503  	links.pads = compat_ptr(pads_ptr);
504  	links.links = compat_ptr(links_ptr);
505  
506  	ret = media_device_enum_links(mdev, &links);
507  	if (ret)
508  		return ret;
509  
510  	if (copy_to_user(ulinks->reserved, links.reserved,
511  			 sizeof(ulinks->reserved)))
512  		return -EFAULT;
513  	return 0;
514  }
515  
516  #define MEDIA_IOC_ENUM_LINKS32		_IOWR('|', 0x02, struct media_links_enum32)
517  
media_device_compat_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)518  static long media_device_compat_ioctl(struct file *filp, unsigned int cmd,
519  				      unsigned long arg)
520  {
521  	struct media_devnode *devnode = media_devnode_data(filp);
522  	struct media_device *dev = devnode->media_dev;
523  	long ret;
524  
525  	switch (cmd) {
526  	case MEDIA_IOC_ENUM_LINKS32:
527  		mutex_lock(&dev->graph_mutex);
528  		ret = media_device_enum_links32(dev,
529  				(struct media_links_enum32 __user *)arg);
530  		mutex_unlock(&dev->graph_mutex);
531  		break;
532  
533  	default:
534  		return media_device_ioctl(filp, cmd, arg);
535  	}
536  
537  	return ret;
538  }
539  #endif /* CONFIG_COMPAT */
540  
541  static const struct media_file_operations media_device_fops = {
542  	.owner = THIS_MODULE,
543  	.open = media_device_open,
544  	.ioctl = media_device_ioctl,
545  #ifdef CONFIG_COMPAT
546  	.compat_ioctl = media_device_compat_ioctl,
547  #endif /* CONFIG_COMPAT */
548  	.release = media_device_close,
549  };
550  
551  /* -----------------------------------------------------------------------------
552   * sysfs
553   */
554  
model_show(struct device * cd,struct device_attribute * attr,char * buf)555  static ssize_t model_show(struct device *cd,
556  			  struct device_attribute *attr, char *buf)
557  {
558  	struct media_devnode *devnode = to_media_devnode(cd);
559  	struct media_device *mdev = devnode->media_dev;
560  
561  	return sprintf(buf, "%.*s\n", (int)sizeof(mdev->model), mdev->model);
562  }
563  
564  static DEVICE_ATTR_RO(model);
565  
566  /* -----------------------------------------------------------------------------
567   * Registration/unregistration
568   */
569  
media_device_release(struct media_devnode * devnode)570  static void media_device_release(struct media_devnode *devnode)
571  {
572  	dev_dbg(devnode->parent, "Media device released\n");
573  }
574  
__media_device_unregister_entity(struct media_entity * entity)575  static void __media_device_unregister_entity(struct media_entity *entity)
576  {
577  	struct media_device *mdev = entity->graph_obj.mdev;
578  	struct media_link *link, *tmp;
579  	struct media_interface *intf;
580  	struct media_pad *iter;
581  
582  	ida_free(&mdev->entity_internal_idx, entity->internal_idx);
583  
584  	/* Remove all interface links pointing to this entity */
585  	list_for_each_entry(intf, &mdev->interfaces, graph_obj.list) {
586  		list_for_each_entry_safe(link, tmp, &intf->links, list) {
587  			if (link->entity == entity)
588  				__media_remove_intf_link(link);
589  		}
590  	}
591  
592  	/* Remove all data links that belong to this entity */
593  	__media_entity_remove_links(entity);
594  
595  	/* Remove all pads that belong to this entity */
596  	media_entity_for_each_pad(entity, iter)
597  		media_gobj_destroy(&iter->graph_obj);
598  
599  	/* Remove the entity */
600  	media_gobj_destroy(&entity->graph_obj);
601  
602  	/* invoke entity_notify callbacks to handle entity removal?? */
603  }
604  
media_device_register_entity(struct media_device * mdev,struct media_entity * entity)605  int __must_check media_device_register_entity(struct media_device *mdev,
606  					      struct media_entity *entity)
607  {
608  	struct media_entity_notify *notify, *next;
609  	struct media_pad *iter;
610  	int ret;
611  
612  	if (entity->function == MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN ||
613  	    entity->function == MEDIA_ENT_F_UNKNOWN)
614  		dev_warn(mdev->dev,
615  			 "Entity type for entity %s was not initialized!\n",
616  			 entity->name);
617  
618  	/* Warn if we apparently re-register an entity */
619  	WARN_ON(entity->graph_obj.mdev != NULL);
620  	entity->graph_obj.mdev = mdev;
621  	INIT_LIST_HEAD(&entity->links);
622  	entity->num_links = 0;
623  	entity->num_backlinks = 0;
624  
625  	ret = ida_alloc_min(&mdev->entity_internal_idx, 1, GFP_KERNEL);
626  	if (ret < 0)
627  		return ret;
628  	entity->internal_idx = ret;
629  
630  	mutex_lock(&mdev->graph_mutex);
631  	mdev->entity_internal_idx_max =
632  		max(mdev->entity_internal_idx_max, entity->internal_idx);
633  
634  	/* Initialize media_gobj embedded at the entity */
635  	media_gobj_create(mdev, MEDIA_GRAPH_ENTITY, &entity->graph_obj);
636  
637  	/* Initialize objects at the pads */
638  	media_entity_for_each_pad(entity, iter)
639  		media_gobj_create(mdev, MEDIA_GRAPH_PAD, &iter->graph_obj);
640  
641  	/* invoke entity_notify callbacks */
642  	list_for_each_entry_safe(notify, next, &mdev->entity_notify, list)
643  		notify->notify(entity, notify->notify_data);
644  
645  	if (mdev->entity_internal_idx_max
646  	    >= mdev->pm_count_walk.ent_enum.idx_max) {
647  		struct media_graph new = { .top = 0 };
648  
649  		/*
650  		 * Initialise the new graph walk before cleaning up
651  		 * the old one in order not to spoil the graph walk
652  		 * object of the media device if graph walk init fails.
653  		 */
654  		ret = media_graph_walk_init(&new, mdev);
655  		if (ret) {
656  			__media_device_unregister_entity(entity);
657  			mutex_unlock(&mdev->graph_mutex);
658  			return ret;
659  		}
660  		media_graph_walk_cleanup(&mdev->pm_count_walk);
661  		mdev->pm_count_walk = new;
662  	}
663  	mutex_unlock(&mdev->graph_mutex);
664  
665  	return 0;
666  }
667  EXPORT_SYMBOL_GPL(media_device_register_entity);
668  
media_device_unregister_entity(struct media_entity * entity)669  void media_device_unregister_entity(struct media_entity *entity)
670  {
671  	struct media_device *mdev = entity->graph_obj.mdev;
672  
673  	if (mdev == NULL)
674  		return;
675  
676  	mutex_lock(&mdev->graph_mutex);
677  	__media_device_unregister_entity(entity);
678  	mutex_unlock(&mdev->graph_mutex);
679  }
680  EXPORT_SYMBOL_GPL(media_device_unregister_entity);
681  
media_device_init(struct media_device * mdev)682  void media_device_init(struct media_device *mdev)
683  {
684  	INIT_LIST_HEAD(&mdev->entities);
685  	INIT_LIST_HEAD(&mdev->interfaces);
686  	INIT_LIST_HEAD(&mdev->pads);
687  	INIT_LIST_HEAD(&mdev->links);
688  	INIT_LIST_HEAD(&mdev->entity_notify);
689  
690  	mutex_init(&mdev->req_queue_mutex);
691  	mutex_init(&mdev->graph_mutex);
692  	ida_init(&mdev->entity_internal_idx);
693  
694  	atomic_set(&mdev->request_id, 0);
695  
696  	if (!*mdev->bus_info)
697  		media_set_bus_info(mdev->bus_info, sizeof(mdev->bus_info),
698  				   mdev->dev);
699  
700  	dev_dbg(mdev->dev, "Media device initialized\n");
701  }
702  EXPORT_SYMBOL_GPL(media_device_init);
703  
media_device_cleanup(struct media_device * mdev)704  void media_device_cleanup(struct media_device *mdev)
705  {
706  	ida_destroy(&mdev->entity_internal_idx);
707  	mdev->entity_internal_idx_max = 0;
708  	media_graph_walk_cleanup(&mdev->pm_count_walk);
709  	mutex_destroy(&mdev->graph_mutex);
710  	mutex_destroy(&mdev->req_queue_mutex);
711  }
712  EXPORT_SYMBOL_GPL(media_device_cleanup);
713  
__media_device_register(struct media_device * mdev,struct module * owner)714  int __must_check __media_device_register(struct media_device *mdev,
715  					 struct module *owner)
716  {
717  	struct media_devnode *devnode;
718  	int ret;
719  
720  	devnode = kzalloc(sizeof(*devnode), GFP_KERNEL);
721  	if (!devnode)
722  		return -ENOMEM;
723  
724  	/* Register the device node. */
725  	mdev->devnode = devnode;
726  	devnode->fops = &media_device_fops;
727  	devnode->parent = mdev->dev;
728  	devnode->release = media_device_release;
729  
730  	/* Set version 0 to indicate user-space that the graph is static */
731  	mdev->topology_version = 0;
732  
733  	ret = media_devnode_register(mdev, devnode, owner);
734  	if (ret < 0) {
735  		/* devnode free is handled in media_devnode_*() */
736  		mdev->devnode = NULL;
737  		return ret;
738  	}
739  
740  	ret = device_create_file(&devnode->dev, &dev_attr_model);
741  	if (ret < 0) {
742  		/* devnode free is handled in media_devnode_*() */
743  		mdev->devnode = NULL;
744  		media_devnode_unregister_prepare(devnode);
745  		media_devnode_unregister(devnode);
746  		return ret;
747  	}
748  
749  	dev_dbg(mdev->dev, "Media device registered\n");
750  
751  	return 0;
752  }
753  EXPORT_SYMBOL_GPL(__media_device_register);
754  
media_device_register_entity_notify(struct media_device * mdev,struct media_entity_notify * nptr)755  void media_device_register_entity_notify(struct media_device *mdev,
756  					struct media_entity_notify *nptr)
757  {
758  	mutex_lock(&mdev->graph_mutex);
759  	list_add_tail(&nptr->list, &mdev->entity_notify);
760  	mutex_unlock(&mdev->graph_mutex);
761  }
762  EXPORT_SYMBOL_GPL(media_device_register_entity_notify);
763  
764  /*
765   * Note: Should be called with mdev->lock held.
766   */
__media_device_unregister_entity_notify(struct media_device * mdev,struct media_entity_notify * nptr)767  static void __media_device_unregister_entity_notify(struct media_device *mdev,
768  					struct media_entity_notify *nptr)
769  {
770  	list_del(&nptr->list);
771  }
772  
media_device_unregister_entity_notify(struct media_device * mdev,struct media_entity_notify * nptr)773  void media_device_unregister_entity_notify(struct media_device *mdev,
774  					struct media_entity_notify *nptr)
775  {
776  	mutex_lock(&mdev->graph_mutex);
777  	__media_device_unregister_entity_notify(mdev, nptr);
778  	mutex_unlock(&mdev->graph_mutex);
779  }
780  EXPORT_SYMBOL_GPL(media_device_unregister_entity_notify);
781  
media_device_unregister(struct media_device * mdev)782  void media_device_unregister(struct media_device *mdev)
783  {
784  	struct media_entity *entity;
785  	struct media_entity *next;
786  	struct media_interface *intf, *tmp_intf;
787  	struct media_entity_notify *notify, *nextp;
788  
789  	if (mdev == NULL)
790  		return;
791  
792  	mutex_lock(&mdev->graph_mutex);
793  
794  	/* Check if mdev was ever registered at all */
795  	if (!media_devnode_is_registered(mdev->devnode)) {
796  		mutex_unlock(&mdev->graph_mutex);
797  		return;
798  	}
799  
800  	/* Clear the devnode register bit to avoid races with media dev open */
801  	media_devnode_unregister_prepare(mdev->devnode);
802  
803  	/* Remove all entities from the media device */
804  	list_for_each_entry_safe(entity, next, &mdev->entities, graph_obj.list)
805  		__media_device_unregister_entity(entity);
806  
807  	/* Remove all entity_notify callbacks from the media device */
808  	list_for_each_entry_safe(notify, nextp, &mdev->entity_notify, list)
809  		__media_device_unregister_entity_notify(mdev, notify);
810  
811  	/* Remove all interfaces from the media device */
812  	list_for_each_entry_safe(intf, tmp_intf, &mdev->interfaces,
813  				 graph_obj.list) {
814  		/*
815  		 * Unlink the interface, but don't free it here; the
816  		 * module which created it is responsible for freeing
817  		 * it
818  		 */
819  		__media_remove_intf_links(intf);
820  		media_gobj_destroy(&intf->graph_obj);
821  	}
822  
823  	mutex_unlock(&mdev->graph_mutex);
824  
825  	dev_dbg(mdev->dev, "Media device unregistered\n");
826  
827  	device_remove_file(&mdev->devnode->dev, &dev_attr_model);
828  	media_devnode_unregister(mdev->devnode);
829  	/* devnode free is handled in media_devnode_*() */
830  	mdev->devnode = NULL;
831  }
832  EXPORT_SYMBOL_GPL(media_device_unregister);
833  
834  #if IS_ENABLED(CONFIG_PCI)
media_device_pci_init(struct media_device * mdev,struct pci_dev * pci_dev,const char * name)835  void media_device_pci_init(struct media_device *mdev,
836  			   struct pci_dev *pci_dev,
837  			   const char *name)
838  {
839  	mdev->dev = &pci_dev->dev;
840  
841  	if (name)
842  		strscpy(mdev->model, name, sizeof(mdev->model));
843  	else
844  		strscpy(mdev->model, pci_name(pci_dev), sizeof(mdev->model));
845  
846  	sprintf(mdev->bus_info, "PCI:%s", pci_name(pci_dev));
847  
848  	mdev->hw_revision = (pci_dev->subsystem_vendor << 16)
849  			    | pci_dev->subsystem_device;
850  
851  	media_device_init(mdev);
852  }
853  EXPORT_SYMBOL_GPL(media_device_pci_init);
854  #endif
855  
856  #if IS_ENABLED(CONFIG_USB)
__media_device_usb_init(struct media_device * mdev,struct usb_device * udev,const char * board_name,const char * driver_name)857  void __media_device_usb_init(struct media_device *mdev,
858  			     struct usb_device *udev,
859  			     const char *board_name,
860  			     const char *driver_name)
861  {
862  	mdev->dev = &udev->dev;
863  
864  	if (driver_name)
865  		strscpy(mdev->driver_name, driver_name,
866  			sizeof(mdev->driver_name));
867  
868  	if (board_name)
869  		strscpy(mdev->model, board_name, sizeof(mdev->model));
870  	else if (udev->product)
871  		strscpy(mdev->model, udev->product, sizeof(mdev->model));
872  	else
873  		strscpy(mdev->model, "unknown model", sizeof(mdev->model));
874  	if (udev->serial)
875  		strscpy(mdev->serial, udev->serial, sizeof(mdev->serial));
876  	usb_make_path(udev, mdev->bus_info, sizeof(mdev->bus_info));
877  	mdev->hw_revision = le16_to_cpu(udev->descriptor.bcdDevice);
878  
879  	media_device_init(mdev);
880  }
881  EXPORT_SYMBOL_GPL(__media_device_usb_init);
882  #endif
883  
884  
885  #endif /* CONFIG_MEDIA_CONTROLLER */
886