drivers/media/media-device.c

   1 /*
   2  * Media device
   3  *
   4  * Copyright (C) 2010 Nokia Corporation
   5  *
   6  * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
   7  *           Sakari Ailus <sakari.ailus@iki.fi>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  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  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 /* We need to access legacy defines from linux/media.h */
  24 #define __NEED_MEDIA_LEGACY_API
  25
  26 #include <linux/compat.h>
  27 #include <linux/export.h>
  28 #include <linux/idr.h>
  29 #include <linux/ioctl.h>
  30 #include <linux/media.h>
  31 #include <linux/slab.h>
  32 #include <linux/types.h>
  33
  34 #include <media/media-device.h>
  35 #include <media/media-devnode.h>
  36 #include <media/media-entity.h>
  37
  38 #ifdef CONFIG_MEDIA_CONTROLLER
  39
  40 /* -----------------------------------------------------------------------------
  41  * Userspace API
  42  */
  43
  44 static int media_device_open(struct file *filp)
  45 {
  46         return 0;
  47 }
  48
  49 static int media_device_close(struct file *filp)
  50 {
  51         return 0;
  52 }
  53
  54 static int media_device_get_info(struct media_device *dev,
  55                                  struct media_device_info __user *__info)
  56 {
  57         struct media_device_info info;
  58
  59         memset(&info, 0, sizeof(info));
  60
  61         strlcpy(info.driver, dev->dev->driver->name, sizeof(info.driver));
  62         strlcpy(info.model, dev->model, sizeof(info.model));
  63         strlcpy(info.serial, dev->serial, sizeof(info.serial));
  64         strlcpy(info.bus_info, dev->bus_info, sizeof(info.bus_info));
  65
  66         info.media_version = MEDIA_API_VERSION;
  67         info.hw_revision = dev->hw_revision;
  68         info.driver_version = dev->driver_version;
  69
  70         if (copy_to_user(__info, &info, sizeof(*__info)))
  71                 return -EFAULT;
  72         return 0;
  73 }
  74
  75 static struct media_entity *find_entity(struct media_device *mdev, u32 id)
  76 {
  77         struct media_entity *entity;
  78         int next = id & MEDIA_ENT_ID_FLAG_NEXT;
  79
  80         id &= ~MEDIA_ENT_ID_FLAG_NEXT;
  81
  82         spin_lock(&mdev->lock);
  83
  84         media_device_for_each_entity(entity, mdev) {
  85                 if (((media_entity_id(entity) == id) && !next) ||
  86                     ((media_entity_id(entity) > id) && next)) {
  87                         spin_unlock(&mdev->lock);
  88                         return entity;
  89                 }
  90         }
  91
  92         spin_unlock(&mdev->lock);
  93
  94         return NULL;
  95 }
  96
  97 static long media_device_enum_entities(struct media_device *mdev,
  98                                        struct media_entity_desc __user *uent)
  99 {
 100         struct media_entity *ent;
 101         struct media_entity_desc u_ent;
 102
 103         memset(&u_ent, 0, sizeof(u_ent));
 104         if (copy_from_user(&u_ent.id, &uent->id, sizeof(u_ent.id)))
 105                 return -EFAULT;
 106
 107         ent = find_entity(mdev, u_ent.id);
 108
 109         if (ent == NULL)
 110                 return -EINVAL;
 111
 112         u_ent.id = media_entity_id(ent);
 113         if (ent->name)
 114                 strlcpy(u_ent.name, ent->name, sizeof(u_ent.name));
 115         u_ent.type = ent->function;
 116         u_ent.revision = 0;             /* Unused */
 117         u_ent.flags = ent->flags;
 118         u_ent.group_id = 0;             /* Unused */
 119         u_ent.pads = ent->num_pads;
 120         u_ent.links = ent->num_links - ent->num_backlinks;
 121
 122         /*
 123          * Workaround for a bug at media-ctl <= v1.10 that makes it to
 124          * do the wrong thing if the entity function doesn't belong to
 125          * either MEDIA_ENT_F_OLD_BASE or MEDIA_ENT_F_OLD_SUBDEV_BASE
 126          * Ranges.
 127          *
 128          * Non-subdevices are expected to be at the MEDIA_ENT_F_OLD_BASE,
 129          * or, otherwise, will be silently ignored by media-ctl when
 130          * printing the graphviz diagram. So, map them into the devnode
 131          * old range.
 132          */
 133         if (ent->function < MEDIA_ENT_F_OLD_BASE ||
 134             ent->function > MEDIA_ENT_T_DEVNODE_UNKNOWN) {
 135                 if (is_media_entity_v4l2_subdev(ent))
 136                         u_ent.type = MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN;
 137                 else if (ent->function != MEDIA_ENT_F_IO_V4L)
 138                         u_ent.type = MEDIA_ENT_T_DEVNODE_UNKNOWN;
 139         }
 140
 141         memcpy(&u_ent.raw, &ent->info, sizeof(ent->info));
 142         if (copy_to_user(uent, &u_ent, sizeof(u_ent)))
 143                 return -EFAULT;
 144         return 0;
 145 }
 146
 147 static void media_device_kpad_to_upad(const struct media_pad *kpad,
 148                                       struct media_pad_desc *upad)
 149 {
 150         upad->entity = media_entity_id(kpad->entity);
 151         upad->index = kpad->index;
 152         upad->flags = kpad->flags;
 153 }
 154
 155 static long __media_device_enum_links(struct media_device *mdev,
 156                                       struct media_links_enum *links)
 157 {
 158         struct media_entity *entity;
 159
 160         entity = find_entity(mdev, links->entity);
 161         if (entity == NULL)
 162                 return -EINVAL;
 163
 164         if (links->pads) {
 165                 unsigned int p;
 166
 167                 for (p = 0; p < entity->num_pads; p++) {
 168                         struct media_pad_desc pad;
 169
 170                         memset(&pad, 0, sizeof(pad));
 171                         media_device_kpad_to_upad(&entity->pads[p], &pad);
 172                         if (copy_to_user(&links->pads[p], &pad, sizeof(pad)))
 173                                 return -EFAULT;
 174                 }
 175         }
 176
 177         if (links->links) {
 178                 struct media_link *link;
 179                 struct media_link_desc __user *ulink_desc = links->links;
 180
 181                 list_for_each_entry(link, &entity->links, list) {
 182                         struct media_link_desc klink_desc;
 183
 184                         /* Ignore backlinks. */
 185                         if (link->source->entity != entity)
 186                                 continue;
 187                         memset(&klink_desc, 0, sizeof(klink_desc));
 188                         media_device_kpad_to_upad(link->source,
 189                                                   &klink_desc.source);
 190                         media_device_kpad_to_upad(link->sink,
 191                                                   &klink_desc.sink);
 192                         klink_desc.flags = link->flags;
 193                         if (copy_to_user(ulink_desc, &klink_desc,
 194                                          sizeof(*ulink_desc)))
 195                                 return -EFAULT;
 196                         ulink_desc++;
 197                 }
 198         }
 199
 200         return 0;
 201 }
 202
 203 static long media_device_enum_links(struct media_device *mdev,
 204                                     struct media_links_enum __user *ulinks)
 205 {
 206         struct media_links_enum links;
 207         int rval;
 208
 209         if (copy_from_user(&links, ulinks, sizeof(links)))
 210                 return -EFAULT;
 211
 212         rval = __media_device_enum_links(mdev, &links);
 213         if (rval < 0)
 214                 return rval;
 215
 216         if (copy_to_user(ulinks, &links, sizeof(*ulinks)))
 217                 return -EFAULT;
 218
 219         return 0;
 220 }
 221
 222 static long media_device_setup_link(struct media_device *mdev,
 223                                     struct media_link_desc __user *_ulink)
 224 {
 225         struct media_link *link = NULL;
 226         struct media_link_desc ulink;
 227         struct media_entity *source;
 228         struct media_entity *sink;
 229         int ret;
 230
 231         if (copy_from_user(&ulink, _ulink, sizeof(ulink)))
 232                 return -EFAULT;
 233
 234         /* Find the source and sink entities and link.
 235          */
 236         source = find_entity(mdev, ulink.source.entity);
 237         sink = find_entity(mdev, ulink.sink.entity);
 238
 239         if (source == NULL || sink == NULL)
 240                 return -EINVAL;
 241
 242         if (ulink.source.index >= source->num_pads ||
 243             ulink.sink.index >= sink->num_pads)
 244                 return -EINVAL;
 245
 246         link = media_entity_find_link(&source->pads[ulink.source.index],
 247                                       &sink->pads[ulink.sink.index]);
 248         if (link == NULL)
 249                 return -EINVAL;
 250
 251         /* Setup the link on both entities. */
 252         ret = __media_entity_setup_link(link, ulink.flags);
 253
 254         if (copy_to_user(_ulink, &ulink, sizeof(ulink)))
 255                 return -EFAULT;
 256
 257         return ret;
 258 }
 259
 260 #if 0 /* Let's postpone it to Kernel 4.6 */
 261 static long __media_device_get_topology(struct media_device *mdev,
 262                                       struct media_v2_topology *topo)
 263 {
 264         struct media_entity *entity;
 265         struct media_interface *intf;
 266         struct media_pad *pad;
 267         struct media_link *link;
 268         struct media_v2_entity kentity, *uentity;
 269         struct media_v2_interface kintf, *uintf;
 270         struct media_v2_pad kpad, *upad;
 271         struct media_v2_link klink, *ulink;
 272         unsigned int i;
 273         int ret = 0;
 274
 275         topo->topology_version = mdev->topology_version;
 276
 277         /* Get entities and number of entities */
 278         i = 0;
 279         uentity = media_get_uptr(topo->ptr_entities);
 280         media_device_for_each_entity(entity, mdev) {
 281                 i++;
 282                 if (ret || !uentity)
 283                         continue;
 284
 285                 if (i > topo->num_entities) {
 286                         ret = -ENOSPC;
 287                         continue;
 288                 }
 289
 290                 /* Copy fields to userspace struct if not error */
 291                 memset(&kentity, 0, sizeof(kentity));
 292                 kentity.id = entity->graph_obj.id;
 293                 kentity.function = entity->function;
 294                 strncpy(kentity.name, entity->name,
 295                         sizeof(kentity.name));
 296
 297                 if (copy_to_user(uentity, &kentity, sizeof(kentity)))
 298                         ret = -EFAULT;
 299                 uentity++;
 300         }
 301         topo->num_entities = i;
 302
 303         /* Get interfaces and number of interfaces */
 304         i = 0;
 305         uintf = media_get_uptr(topo->ptr_interfaces);
 306         media_device_for_each_intf(intf, mdev) {
 307                 i++;
 308                 if (ret || !uintf)
 309                         continue;
 310
 311                 if (i > topo->num_interfaces) {
 312                         ret = -ENOSPC;
 313                         continue;
 314                 }
 315
 316                 memset(&kintf, 0, sizeof(kintf));
 317
 318                 /* Copy intf fields to userspace struct */
 319                 kintf.id = intf->graph_obj.id;
 320                 kintf.intf_type = intf->type;
 321                 kintf.flags = intf->flags;
 322
 323                 if (media_type(&intf->graph_obj) == MEDIA_GRAPH_INTF_DEVNODE) {
 324                         struct media_intf_devnode *devnode;
 325
 326                         devnode = intf_to_devnode(intf);
 327
 328                         kintf.devnode.major = devnode->major;
 329                         kintf.devnode.minor = devnode->minor;
 330                 }
 331
 332                 if (copy_to_user(uintf, &kintf, sizeof(kintf)))
 333                         ret = -EFAULT;
 334                 uintf++;
 335         }
 336         topo->num_interfaces = i;
 337
 338         /* Get pads and number of pads */
 339         i = 0;
 340         upad = media_get_uptr(topo->ptr_pads);
 341         media_device_for_each_pad(pad, mdev) {
 342                 i++;
 343                 if (ret || !upad)
 344                         continue;
 345
 346                 if (i > topo->num_pads) {
 347                         ret = -ENOSPC;
 348                         continue;
 349                 }
 350
 351                 memset(&kpad, 0, sizeof(kpad));
 352
 353                 /* Copy pad fields to userspace struct */
 354                 kpad.id = pad->graph_obj.id;
 355                 kpad.entity_id = pad->entity->graph_obj.id;
 356                 kpad.flags = pad->flags;
 357
 358                 if (copy_to_user(upad, &kpad, sizeof(kpad)))
 359                         ret = -EFAULT;
 360                 upad++;
 361         }
 362         topo->num_pads = i;
 363
 364         /* Get links and number of links */
 365         i = 0;
 366         ulink = media_get_uptr(topo->ptr_links);
 367         media_device_for_each_link(link, mdev) {
 368                 if (link->is_backlink)
 369                         continue;
 370
 371                 i++;
 372
 373                 if (ret || !ulink)
 374                         continue;
 375
 376                 if (i > topo->num_links) {
 377                         ret = -ENOSPC;
 378                         continue;
 379                 }
 380
 381                 memset(&klink, 0, sizeof(klink));
 382
 383                 /* Copy link fields to userspace struct */
 384                 klink.id = link->graph_obj.id;
 385                 klink.source_id = link->gobj0->id;
 386                 klink.sink_id = link->gobj1->id;
 387                 klink.flags = link->flags;
 388
 389                 if (copy_to_user(ulink, &klink, sizeof(klink)))
 390                         ret = -EFAULT;
 391                 ulink++;
 392         }
 393         topo->num_links = i;
 394
 395         return ret;
 396 }
 397
 398 static long media_device_get_topology(struct media_device *mdev,
 399                                       struct media_v2_topology __user *utopo)
 400 {
 401         struct media_v2_topology ktopo;
 402         int ret;
 403
 404         if (copy_from_user(&ktopo, utopo, sizeof(ktopo)))
 405                 return -EFAULT;
 406
 407         ret = __media_device_get_topology(mdev, &ktopo);
 408         if (ret < 0)
 409                 return ret;
 410
 411         if (copy_to_user(utopo, &ktopo, sizeof(*utopo)))
 412                 return -EFAULT;
 413
 414         return 0;
 415 }
 416 #endif
 417
 418 static long media_device_ioctl(struct file *filp, unsigned int cmd,
 419                                unsigned long arg)
 420 {
 421         struct media_devnode *devnode = media_devnode_data(filp);
 422         struct media_device *dev = to_media_device(devnode);
 423         long ret;
 424
 425         switch (cmd) {
 426         case MEDIA_IOC_DEVICE_INFO:
 427                 ret = media_device_get_info(dev,
 428                                 (struct media_device_info __user *)arg);
 429                 break;
 430
 431         case MEDIA_IOC_ENUM_ENTITIES:
 432                 ret = media_device_enum_entities(dev,
 433                                 (struct media_entity_desc __user *)arg);
 434                 break;
 435
 436         case MEDIA_IOC_ENUM_LINKS:
 437                 mutex_lock(&dev->graph_mutex);
 438                 ret = media_device_enum_links(dev,
 439                                 (struct media_links_enum __user *)arg);
 440                 mutex_unlock(&dev->graph_mutex);
 441                 break;
 442
 443         case MEDIA_IOC_SETUP_LINK:
 444                 mutex_lock(&dev->graph_mutex);
 445                 ret = media_device_setup_link(dev,
 446                                 (struct media_link_desc __user *)arg);
 447                 mutex_unlock(&dev->graph_mutex);
 448                 break;
 449
 450 #if 0 /* Let's postpone it to Kernel 4.6 */
 451         case MEDIA_IOC_G_TOPOLOGY:
 452                 mutex_lock(&dev->graph_mutex);
 453                 ret = media_device_get_topology(dev,
 454                                 (struct media_v2_topology __user *)arg);
 455                 mutex_unlock(&dev->graph_mutex);
 456                 break;
 457 #endif
 458         default:
 459                 ret = -ENOIOCTLCMD;
 460         }
 461
 462         return ret;
 463 }
 464
 465 #ifdef CONFIG_COMPAT
 466
 467 struct media_links_enum32 {
 468         __u32 entity;
 469         compat_uptr_t pads; /* struct media_pad_desc * */
 470         compat_uptr_t links; /* struct media_link_desc * */
 471         __u32 reserved[4];
 472 };
 473
 474 static long media_device_enum_links32(struct media_device *mdev,
 475                                       struct media_links_enum32 __user *ulinks)
 476 {
 477         struct media_links_enum links;
 478         compat_uptr_t pads_ptr, links_ptr;
 479
 480         memset(&links, 0, sizeof(links));
 481
 482         if (get_user(links.entity, &ulinks->entity)
 483             || get_user(pads_ptr, &ulinks->pads)
 484             || get_user(links_ptr, &ulinks->links))
 485                 return -EFAULT;
 486
 487         links.pads = compat_ptr(pads_ptr);
 488         links.links = compat_ptr(links_ptr);
 489
 490         return __media_device_enum_links(mdev, &links);
 491 }
 492
 493 #define MEDIA_IOC_ENUM_LINKS32          _IOWR('|', 0x02, struct media_links_enum32)
 494
 495 static long media_device_compat_ioctl(struct file *filp, unsigned int cmd,
 496                                       unsigned long arg)
 497 {
 498         struct media_devnode *devnode = media_devnode_data(filp);
 499         struct media_device *dev = to_media_device(devnode);
 500         long ret;
 501
 502         switch (cmd) {
 503         case MEDIA_IOC_DEVICE_INFO:
 504         case MEDIA_IOC_ENUM_ENTITIES:
 505         case MEDIA_IOC_SETUP_LINK:
 506 #if 0 /* Let's postpone it to Kernel 4.6 */
 507         case MEDIA_IOC_G_TOPOLOGY:
 508 #endif
 509                 return media_device_ioctl(filp, cmd, arg);
 510
 511         case MEDIA_IOC_ENUM_LINKS32:
 512                 mutex_lock(&dev->graph_mutex);
 513                 ret = media_device_enum_links32(dev,
 514                                 (struct media_links_enum32 __user *)arg);
 515                 mutex_unlock(&dev->graph_mutex);
 516                 break;
 517
 518         default:
 519                 ret = -ENOIOCTLCMD;
 520         }
 521
 522         return ret;
 523 }
 524 #endif /* CONFIG_COMPAT */
 525
 526 static const struct media_file_operations media_device_fops = {
 527         .owner = THIS_MODULE,
 528         .open = media_device_open,
 529         .ioctl = media_device_ioctl,
 530 #ifdef CONFIG_COMPAT
 531         .compat_ioctl = media_device_compat_ioctl,
 532 #endif /* CONFIG_COMPAT */
 533         .release = media_device_close,
 534 };
 535
 536 /* -----------------------------------------------------------------------------
 537  * sysfs
 538  */
 539
 540 static ssize_t show_model(struct device *cd,
 541                           struct device_attribute *attr, char *buf)
 542 {
 543         struct media_device *mdev = to_media_device(to_media_devnode(cd));
 544
 545         return sprintf(buf, "%.*s\n", (int)sizeof(mdev->model), mdev->model);
 546 }
 547
 548 static DEVICE_ATTR(model, S_IRUGO, show_model, NULL);
 549
 550 /* -----------------------------------------------------------------------------
 551  * Registration/unregistration
 552  */
 553
 554 static void media_device_release(struct media_devnode *mdev)
 555 {
 556         dev_dbg(mdev->parent, "Media device released\n");
 557 }
 558
 559 /**
 560  * media_device_register_entity - Register an entity with a media device
 561  * @mdev:       The media device
 562  * @entity:     The entity
 563  */
 564 int __must_check media_device_register_entity(struct media_device *mdev,
 565                                               struct media_entity *entity)
 566 {
 567         unsigned int i;
 568         int ret;
 569
 570         if (entity->function == MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN ||
 571             entity->function == MEDIA_ENT_F_UNKNOWN)
 572                 dev_warn(mdev->dev,
 573                          "Entity type for entity %s was not initialized!\n",
 574                          entity->name);
 575
 576         /* Warn if we apparently re-register an entity */
 577         WARN_ON(entity->graph_obj.mdev != NULL);
 578         entity->graph_obj.mdev = mdev;
 579         INIT_LIST_HEAD(&entity->links);
 580         entity->num_links = 0;
 581         entity->num_backlinks = 0;
 582
 583         if (!ida_pre_get(&mdev->entity_internal_idx, GFP_KERNEL))
 584                 return -ENOMEM;
 585
 586         spin_lock(&mdev->lock);
 587
 588         ret = ida_get_new_above(&mdev->entity_internal_idx, 1,
 589                                 &entity->internal_idx);
 590         if (ret < 0) {
 591                 spin_unlock(&mdev->lock);
 592                 return ret;
 593         }
 594
 595         mdev->entity_internal_idx_max =
 596                 max(mdev->entity_internal_idx_max, entity->internal_idx);
 597
 598         /* Initialize media_gobj embedded at the entity */
 599         media_gobj_create(mdev, MEDIA_GRAPH_ENTITY, &entity->graph_obj);
 600
 601         /* Initialize objects at the pads */
 602         for (i = 0; i < entity->num_pads; i++)
 603                 media_gobj_create(mdev, MEDIA_GRAPH_PAD,
 604                                &entity->pads[i].graph_obj);
 605
 606         spin_unlock(&mdev->lock);
 607
 608         return 0;
 609 }
 610 EXPORT_SYMBOL_GPL(media_device_register_entity);
 611
 612 static void __media_device_unregister_entity(struct media_entity *entity)
 613 {
 614         struct media_device *mdev = entity->graph_obj.mdev;
 615         struct media_link *link, *tmp;
 616         struct media_interface *intf;
 617         unsigned int i;
 618
 619         ida_simple_remove(&mdev->entity_internal_idx, entity->internal_idx);
 620
 621         /* Remove all interface links pointing to this entity */
 622         list_for_each_entry(intf, &mdev->interfaces, graph_obj.list) {
 623                 list_for_each_entry_safe(link, tmp, &intf->links, list) {
 624                         if (link->entity == entity)
 625                                 __media_remove_intf_link(link);
 626                 }
 627         }
 628
 629         /* Remove all data links that belong to this entity */
 630         __media_entity_remove_links(entity);
 631
 632         /* Remove all pads that belong to this entity */
 633         for (i = 0; i < entity->num_pads; i++)
 634                 media_gobj_destroy(&entity->pads[i].graph_obj);
 635
 636         /* Remove the entity */
 637         media_gobj_destroy(&entity->graph_obj);
 638
 639         entity->graph_obj.mdev = NULL;
 640 }
 641
 642 void media_device_unregister_entity(struct media_entity *entity)
 643 {
 644         struct media_device *mdev = entity->graph_obj.mdev;
 645
 646         if (mdev == NULL)
 647                 return;
 648
 649         spin_lock(&mdev->lock);
 650         __media_device_unregister_entity(entity);
 651         spin_unlock(&mdev->lock);
 652 }
 653 EXPORT_SYMBOL_GPL(media_device_unregister_entity);
 654
 655 /**
 656  * media_device_init() - initialize a media device
 657  * @mdev:       The media device
 658  *
 659  * The caller is responsible for initializing the media device before
 660  * registration. The following fields must be set:
 661  *
 662  * - dev must point to the parent device
 663  * - model must be filled with the device model name
 664  */
 665 void media_device_init(struct media_device *mdev)
 666 {
 667         INIT_LIST_HEAD(&mdev->entities);
 668         INIT_LIST_HEAD(&mdev->interfaces);
 669         INIT_LIST_HEAD(&mdev->pads);
 670         INIT_LIST_HEAD(&mdev->links);
 671         spin_lock_init(&mdev->lock);
 672         mutex_init(&mdev->graph_mutex);
 673         ida_init(&mdev->entity_internal_idx);
 674
 675         dev_dbg(mdev->dev, "Media device initialized\n");
 676 }
 677 EXPORT_SYMBOL_GPL(media_device_init);
 678
 679 void media_device_cleanup(struct media_device *mdev)
 680 {
 681         ida_destroy(&mdev->entity_internal_idx);
 682         mdev->entity_internal_idx_max = 0;
 683         mutex_destroy(&mdev->graph_mutex);
 684 }
 685 EXPORT_SYMBOL_GPL(media_device_cleanup);
 686
 687 int __must_check __media_device_register(struct media_device *mdev,
 688                                          struct module *owner)
 689 {
 690         int ret;
 691
 692         /* Register the device node. */
 693         mdev->devnode.fops = &media_device_fops;
 694         mdev->devnode.parent = mdev->dev;
 695         mdev->devnode.release = media_device_release;
 696
 697         /* Set version 0 to indicate user-space that the graph is static */
 698         mdev->topology_version = 0;
 699
 700         ret = media_devnode_register(&mdev->devnode, owner);
 701         if (ret < 0)
 702                 return ret;
 703
 704         ret = device_create_file(&mdev->devnode.dev, &dev_attr_model);
 705         if (ret < 0) {
 706                 media_devnode_unregister(&mdev->devnode);
 707                 return ret;
 708         }
 709
 710         dev_dbg(mdev->dev, "Media device registered\n");
 711
 712         return 0;
 713 }
 714 EXPORT_SYMBOL_GPL(__media_device_register);
 715
 716 void media_device_unregister(struct media_device *mdev)
 717 {
 718         struct media_entity *entity;
 719         struct media_entity *next;
 720         struct media_interface *intf, *tmp_intf;
 721
 722         if (mdev == NULL)
 723                 return;
 724
 725         spin_lock(&mdev->lock);
 726
 727         /* Check if mdev was ever registered at all */
 728         if (!media_devnode_is_registered(&mdev->devnode)) {
 729                 spin_unlock(&mdev->lock);
 730                 return;
 731         }
 732
 733         /* Remove all entities from the media device */
 734         list_for_each_entry_safe(entity, next, &mdev->entities, graph_obj.list)
 735                 __media_device_unregister_entity(entity);
 736
 737         /* Remove all interfaces from the media device */
 738         list_for_each_entry_safe(intf, tmp_intf, &mdev->interfaces,
 739                                  graph_obj.list) {
 740                 __media_remove_intf_links(intf);
 741                 media_gobj_destroy(&intf->graph_obj);
 742                 kfree(intf);
 743         }
 744
 745         spin_unlock(&mdev->lock);
 746
 747         device_remove_file(&mdev->devnode.dev, &dev_attr_model);
 748         media_devnode_unregister(&mdev->devnode);
 749
 750         dev_dbg(mdev->dev, "Media device unregistered\n");
 751 }
 752 EXPORT_SYMBOL_GPL(media_device_unregister);
 753
 754 static void media_device_release_devres(struct device *dev, void *res)
 755 {
 756 }
 757
 758 struct media_device *media_device_get_devres(struct device *dev)
 759 {
 760         struct media_device *mdev;
 761
 762         mdev = devres_find(dev, media_device_release_devres, NULL, NULL);
 763         if (mdev)
 764                 return mdev;
 765
 766         mdev = devres_alloc(media_device_release_devres,
 767                                 sizeof(struct media_device), GFP_KERNEL);
 768         if (!mdev)
 769                 return NULL;
 770         return devres_get(dev, mdev, NULL, NULL);
 771 }
 772 EXPORT_SYMBOL_GPL(media_device_get_devres);
 773
 774 struct media_device *media_device_find_devres(struct device *dev)
 775 {
 776         return devres_find(dev, media_device_release_devres, NULL, NULL);
 777 }
 778 EXPORT_SYMBOL_GPL(media_device_find_devres);
 779
 780 #endif /* CONFIG_MEDIA_CONTROLLER */