drivers/media/mc/mc-device.c

   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
  43 static inline void __user *media_get_uptr(__u64 arg)
  44 {
  45         return (void __user *)(uintptr_t)arg;
  46 }
  47
  48 static int media_device_open(struct file *filp)
  49 {
  50         return 0;
  51 }
  52
  53 static int media_device_close(struct file *filp)
  54 {
  55         return 0;
  56 }
  57
  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
  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
  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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 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
 570 static void media_device_release(struct media_devnode *devnode)
 571 {
 572         dev_dbg(devnode->parent, "Media device released\n");
 573 }
 574
 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
 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
 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
 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
 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
 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
 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  */
 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
 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
 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)
 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)
 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 */