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 #include <linux/pci.h>
  34 #include <linux/usb.h>
  35
  36 #include <media/media-device.h>
  37 #include <media/media-devnode.h>
  38 #include <media/media-entity.h>
  39
  40 #ifdef CONFIG_MEDIA_CONTROLLER
  41
  42 /* -----------------------------------------------------------------------------
  43  * Userspace API
  44  */
  45
  46 static inline void __user *media_get_uptr(__u64 arg)
  47 {
  48         return (void __user *)(uintptr_t)arg;
  49 }
  50
  51 static int media_device_open(struct file *filp)
  52 {
  53         return 0;
  54 }
  55
  56 static int media_device_close(struct file *filp)
  57 {
  58         return 0;
  59 }
  60
  61 static long media_device_get_info(struct media_device *dev, void *arg)
  62 {
  63         struct media_device_info *info = arg;
  64
  65         memset(info, 0, sizeof(*info));
  66
  67         if (dev->driver_name[0])
  68                 strlcpy(info->driver, dev->driver_name, sizeof(info->driver));
  69         else
  70                 strlcpy(info->driver, dev->dev->driver->name,
  71                         sizeof(info->driver));
  72
  73         strlcpy(info->model, dev->model, sizeof(info->model));
  74         strlcpy(info->serial, dev->serial, sizeof(info->serial));
  75         strlcpy(info->bus_info, dev->bus_info, sizeof(info->bus_info));
  76
  77         info->media_version = MEDIA_API_VERSION;
  78         info->hw_revision = dev->hw_revision;
  79         info->driver_version = dev->driver_version;
  80
  81         return 0;
  82 }
  83
  84 static struct media_entity *find_entity(struct media_device *mdev, u32 id)
  85 {
  86         struct media_entity *entity;
  87         int next = id & MEDIA_ENT_ID_FLAG_NEXT;
  88
  89         id &= ~MEDIA_ENT_ID_FLAG_NEXT;
  90
  91         media_device_for_each_entity(entity, mdev) {
  92                 if (((media_entity_id(entity) == id) && !next) ||
  93                     ((media_entity_id(entity) > id) && next)) {
  94                         return entity;
  95                 }
  96         }
  97
  98         return NULL;
  99 }
 100
 101 static long media_device_enum_entities(struct media_device *mdev, void *arg)
 102 {
 103         struct media_entity_desc *entd = arg;
 104         struct media_entity *ent;
 105
 106         ent = find_entity(mdev, entd->id);
 107         if (ent == NULL)
 108                 return -EINVAL;
 109
 110         memset(entd, 0, sizeof(*entd));
 111
 112         entd->id = media_entity_id(ent);
 113         if (ent->name)
 114                 strlcpy(entd->name, ent->name, sizeof(entd->name));
 115         entd->type = ent->function;
 116         entd->revision = 0;             /* Unused */
 117         entd->flags = ent->flags;
 118         entd->group_id = 0;             /* Unused */
 119         entd->pads = ent->num_pads;
 120         entd->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_F_TUNER) {
 135                 if (is_media_entity_v4l2_subdev(ent))
 136                         entd->type = MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN;
 137                 else if (ent->function != MEDIA_ENT_F_IO_V4L)
 138                         entd->type = MEDIA_ENT_T_DEVNODE_UNKNOWN;
 139         }
 140
 141         memcpy(&entd->raw, &ent->info, sizeof(ent->info));
 142
 143         return 0;
 144 }
 145
 146 static void media_device_kpad_to_upad(const struct media_pad *kpad,
 147                                       struct media_pad_desc *upad)
 148 {
 149         upad->entity = media_entity_id(kpad->entity);
 150         upad->index = kpad->index;
 151         upad->flags = kpad->flags;
 152 }
 153
 154 static long media_device_enum_links(struct media_device *mdev, void *arg)
 155 {
 156         struct media_links_enum *links = arg;
 157         struct media_entity *entity;
 158
 159         entity = find_entity(mdev, links->entity);
 160         if (entity == NULL)
 161                 return -EINVAL;
 162
 163         if (links->pads) {
 164                 unsigned int p;
 165
 166                 for (p = 0; p < entity->num_pads; p++) {
 167                         struct media_pad_desc pad;
 168
 169                         memset(&pad, 0, sizeof(pad));
 170                         media_device_kpad_to_upad(&entity->pads[p], &pad);
 171                         if (copy_to_user(&links->pads[p], &pad, sizeof(pad)))
 172                                 return -EFAULT;
 173                 }
 174         }
 175
 176         if (links->links) {
 177                 struct media_link *link;
 178                 struct media_link_desc __user *ulink_desc = links->links;
 179
 180                 list_for_each_entry(link, &entity->links, list) {
 181                         struct media_link_desc klink_desc;
 182
 183                         /* Ignore backlinks. */
 184                         if (link->source->entity != entity)
 185                                 continue;
 186                         memset(&klink_desc, 0, sizeof(klink_desc));
 187                         media_device_kpad_to_upad(link->source,
 188                                                   &klink_desc.source);
 189                         media_device_kpad_to_upad(link->sink,
 190                                                   &klink_desc.sink);
 191                         klink_desc.flags = link->flags;
 192                         if (copy_to_user(ulink_desc, &klink_desc,
 193                                          sizeof(*ulink_desc)))
 194                                 return -EFAULT;
 195                         ulink_desc++;
 196                 }
 197         }
 198
 199         return 0;
 200 }
 201
 202 static long media_device_setup_link(struct media_device *mdev, void *arg)
 203 {
 204         struct media_link_desc *linkd = arg;
 205         struct media_link *link = NULL;
 206         struct media_entity *source;
 207         struct media_entity *sink;
 208
 209         /* Find the source and sink entities and link.
 210          */
 211         source = find_entity(mdev, linkd->source.entity);
 212         sink = find_entity(mdev, linkd->sink.entity);
 213
 214         if (source == NULL || sink == NULL)
 215                 return -EINVAL;
 216
 217         if (linkd->source.index >= source->num_pads ||
 218             linkd->sink.index >= sink->num_pads)
 219                 return -EINVAL;
 220
 221         link = media_entity_find_link(&source->pads[linkd->source.index],
 222                                       &sink->pads[linkd->sink.index]);
 223         if (link == NULL)
 224                 return -EINVAL;
 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                 strncpy(kentity.name, entity->name,
 264                         sizeof(kentity.name));
 265
 266                 if (copy_to_user(uentity, &kentity, sizeof(kentity)))
 267                         ret = -EFAULT;
 268                 uentity++;
 269         }
 270         topo->num_entities = i;
 271
 272         /* Get interfaces and number of interfaces */
 273         i = 0;
 274         uintf = media_get_uptr(topo->ptr_interfaces);
 275         media_device_for_each_intf(intf, mdev) {
 276                 i++;
 277                 if (ret || !uintf)
 278                         continue;
 279
 280                 if (i > topo->num_interfaces) {
 281                         ret = -ENOSPC;
 282                         continue;
 283                 }
 284
 285                 memset(&kintf, 0, sizeof(kintf));
 286
 287                 /* Copy intf fields to userspace struct */
 288                 kintf.id = intf->graph_obj.id;
 289                 kintf.intf_type = intf->type;
 290                 kintf.flags = intf->flags;
 291
 292                 if (media_type(&intf->graph_obj) == MEDIA_GRAPH_INTF_DEVNODE) {
 293                         struct media_intf_devnode *devnode;
 294
 295                         devnode = intf_to_devnode(intf);
 296
 297                         kintf.devnode.major = devnode->major;
 298                         kintf.devnode.minor = devnode->minor;
 299                 }
 300
 301                 if (copy_to_user(uintf, &kintf, sizeof(kintf)))
 302                         ret = -EFAULT;
 303                 uintf++;
 304         }
 305         topo->num_interfaces = i;
 306
 307         /* Get pads and number of pads */
 308         i = 0;
 309         upad = media_get_uptr(topo->ptr_pads);
 310         media_device_for_each_pad(pad, mdev) {
 311                 i++;
 312                 if (ret || !upad)
 313                         continue;
 314
 315                 if (i > topo->num_pads) {
 316                         ret = -ENOSPC;
 317                         continue;
 318                 }
 319
 320                 memset(&kpad, 0, sizeof(kpad));
 321
 322                 /* Copy pad fields to userspace struct */
 323                 kpad.id = pad->graph_obj.id;
 324                 kpad.entity_id = pad->entity->graph_obj.id;
 325                 kpad.flags = pad->flags;
 326
 327                 if (copy_to_user(upad, &kpad, sizeof(kpad)))
 328                         ret = -EFAULT;
 329                 upad++;
 330         }
 331         topo->num_pads = i;
 332
 333         /* Get links and number of links */
 334         i = 0;
 335         ulink = media_get_uptr(topo->ptr_links);
 336         media_device_for_each_link(link, mdev) {
 337                 if (link->is_backlink)
 338                         continue;
 339
 340                 i++;
 341
 342                 if (ret || !ulink)
 343                         continue;
 344
 345                 if (i > topo->num_links) {
 346                         ret = -ENOSPC;
 347                         continue;
 348                 }
 349
 350                 memset(&klink, 0, sizeof(klink));
 351
 352                 /* Copy link fields to userspace struct */
 353                 klink.id = link->graph_obj.id;
 354                 klink.source_id = link->gobj0->id;
 355                 klink.sink_id = link->gobj1->id;
 356                 klink.flags = link->flags;
 357
 358                 if (copy_to_user(ulink, &klink, sizeof(klink)))
 359                         ret = -EFAULT;
 360                 ulink++;
 361         }
 362         topo->num_links = i;
 363
 364         return ret;
 365 }
 366
 367 static long copy_arg_from_user(void *karg, void __user *uarg, unsigned int cmd)
 368 {
 369         /* All media IOCTLs are _IOWR() */
 370         if (copy_from_user(karg, uarg, _IOC_SIZE(cmd)))
 371                 return -EFAULT;
 372
 373         return 0;
 374 }
 375
 376 static long copy_arg_to_user(void __user *uarg, void *karg, unsigned int cmd)
 377 {
 378         /* All media IOCTLs are _IOWR() */
 379         if (copy_to_user(uarg, karg, _IOC_SIZE(cmd)))
 380                 return -EFAULT;
 381
 382         return 0;
 383 }
 384
 385 /* Do acquire the graph mutex */
 386 #define MEDIA_IOC_FL_GRAPH_MUTEX        BIT(0)
 387
 388 #define MEDIA_IOC_ARG(__cmd, func, fl, from_user, to_user)              \
 389         [_IOC_NR(MEDIA_IOC_##__cmd)] = {                                \
 390                 .cmd = MEDIA_IOC_##__cmd,                               \
 391                 .fn = (long (*)(struct media_device *, void *))func,    \
 392                 .flags = fl,                                            \
 393                 .arg_from_user = from_user,                             \
 394                 .arg_to_user = to_user,                                 \
 395         }
 396
 397 #define MEDIA_IOC(__cmd, func, fl)                                      \
 398         MEDIA_IOC_ARG(__cmd, func, fl, copy_arg_from_user, copy_arg_to_user)
 399
 400 /* the table is indexed by _IOC_NR(cmd) */
 401 struct media_ioctl_info {
 402         unsigned int cmd;
 403         unsigned short flags;
 404         long (*fn)(struct media_device *dev, void *arg);
 405         long (*arg_from_user)(void *karg, void __user *uarg, unsigned int cmd);
 406         long (*arg_to_user)(void __user *uarg, void *karg, unsigned int cmd);
 407 };
 408
 409 static const struct media_ioctl_info ioctl_info[] = {
 410         MEDIA_IOC(DEVICE_INFO, media_device_get_info, MEDIA_IOC_FL_GRAPH_MUTEX),
 411         MEDIA_IOC(ENUM_ENTITIES, media_device_enum_entities, MEDIA_IOC_FL_GRAPH_MUTEX),
 412         MEDIA_IOC(ENUM_LINKS, media_device_enum_links, MEDIA_IOC_FL_GRAPH_MUTEX),
 413         MEDIA_IOC(SETUP_LINK, media_device_setup_link, MEDIA_IOC_FL_GRAPH_MUTEX),
 414         MEDIA_IOC(G_TOPOLOGY, media_device_get_topology, MEDIA_IOC_FL_GRAPH_MUTEX),
 415 };
 416
 417 static long media_device_ioctl(struct file *filp, unsigned int cmd,
 418                                unsigned long __arg)
 419 {
 420         struct media_devnode *devnode = media_devnode_data(filp);
 421         struct media_device *dev = devnode->media_dev;
 422         const struct media_ioctl_info *info;
 423         void __user *arg = (void __user *)__arg;
 424         char __karg[256], *karg = __karg;
 425         long ret;
 426
 427         if (_IOC_NR(cmd) >= ARRAY_SIZE(ioctl_info)
 428             || ioctl_info[_IOC_NR(cmd)].cmd != cmd)
 429                 return -ENOIOCTLCMD;
 430
 431         info = &ioctl_info[_IOC_NR(cmd)];
 432
 433         if (_IOC_SIZE(info->cmd) > sizeof(__karg)) {
 434                 karg = kmalloc(_IOC_SIZE(info->cmd), GFP_KERNEL);
 435                 if (!karg)
 436                         return -ENOMEM;
 437         }
 438
 439         if (info->arg_from_user) {
 440                 ret = info->arg_from_user(karg, arg, cmd);
 441                 if (ret)
 442                         goto out_free;
 443         }
 444
 445         if (info->flags & MEDIA_IOC_FL_GRAPH_MUTEX)
 446                 mutex_lock(&dev->graph_mutex);
 447
 448         ret = info->fn(dev, karg);
 449
 450         if (info->flags & MEDIA_IOC_FL_GRAPH_MUTEX)
 451                 mutex_unlock(&dev->graph_mutex);
 452
 453         if (!ret && info->arg_to_user)
 454                 ret = info->arg_to_user(arg, karg, cmd);
 455
 456 out_free:
 457         if (karg != __karg)
 458                 kfree(karg);
 459
 460         return ret;
 461 }
 462
 463 #ifdef CONFIG_COMPAT
 464
 465 struct media_links_enum32 {
 466         __u32 entity;
 467         compat_uptr_t pads; /* struct media_pad_desc * */
 468         compat_uptr_t links; /* struct media_link_desc * */
 469         __u32 reserved[4];
 470 };
 471
 472 static long media_device_enum_links32(struct media_device *mdev,
 473                                       struct media_links_enum32 __user *ulinks)
 474 {
 475         struct media_links_enum links;
 476         compat_uptr_t pads_ptr, links_ptr;
 477
 478         memset(&links, 0, sizeof(links));
 479
 480         if (get_user(links.entity, &ulinks->entity)
 481             || get_user(pads_ptr, &ulinks->pads)
 482             || get_user(links_ptr, &ulinks->links))
 483                 return -EFAULT;
 484
 485         links.pads = compat_ptr(pads_ptr);
 486         links.links = compat_ptr(links_ptr);
 487
 488         return media_device_enum_links(mdev, &links);
 489 }
 490
 491 #define MEDIA_IOC_ENUM_LINKS32          _IOWR('|', 0x02, struct media_links_enum32)
 492
 493 static long media_device_compat_ioctl(struct file *filp, unsigned int cmd,
 494                                       unsigned long arg)
 495 {
 496         struct media_devnode *devnode = media_devnode_data(filp);
 497         struct media_device *dev = devnode->media_dev;
 498         long ret;
 499
 500         switch (cmd) {
 501         case MEDIA_IOC_ENUM_LINKS32:
 502                 mutex_lock(&dev->graph_mutex);
 503                 ret = media_device_enum_links32(dev,
 504                                 (struct media_links_enum32 __user *)arg);
 505                 mutex_unlock(&dev->graph_mutex);
 506                 break;
 507
 508         default:
 509                 return media_device_ioctl(filp, cmd, arg);
 510         }
 511
 512         return ret;
 513 }
 514 #endif /* CONFIG_COMPAT */
 515
 516 static const struct media_file_operations media_device_fops = {
 517         .owner = THIS_MODULE,
 518         .open = media_device_open,
 519         .ioctl = media_device_ioctl,
 520 #ifdef CONFIG_COMPAT
 521         .compat_ioctl = media_device_compat_ioctl,
 522 #endif /* CONFIG_COMPAT */
 523         .release = media_device_close,
 524 };
 525
 526 /* -----------------------------------------------------------------------------
 527  * sysfs
 528  */
 529
 530 static ssize_t show_model(struct device *cd,
 531                           struct device_attribute *attr, char *buf)
 532 {
 533         struct media_devnode *devnode = to_media_devnode(cd);
 534         struct media_device *mdev = devnode->media_dev;
 535
 536         return sprintf(buf, "%.*s\n", (int)sizeof(mdev->model), mdev->model);
 537 }
 538
 539 static DEVICE_ATTR(model, S_IRUGO, show_model, NULL);
 540
 541 /* -----------------------------------------------------------------------------
 542  * Registration/unregistration
 543  */
 544
 545 static void media_device_release(struct media_devnode *mdev)
 546 {
 547         dev_dbg(mdev->parent, "Media device released\n");
 548 }
 549
 550 /**
 551  * media_device_register_entity - Register an entity with a media device
 552  * @mdev:       The media device
 553  * @entity:     The entity
 554  */
 555 int __must_check media_device_register_entity(struct media_device *mdev,
 556                                               struct media_entity *entity)
 557 {
 558         struct media_entity_notify *notify, *next;
 559         unsigned int i;
 560         int ret;
 561
 562         if (entity->function == MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN ||
 563             entity->function == MEDIA_ENT_F_UNKNOWN)
 564                 dev_warn(mdev->dev,
 565                          "Entity type for entity %s was not initialized!\n",
 566                          entity->name);
 567
 568         /* Warn if we apparently re-register an entity */
 569         WARN_ON(entity->graph_obj.mdev != NULL);
 570         entity->graph_obj.mdev = mdev;
 571         INIT_LIST_HEAD(&entity->links);
 572         entity->num_links = 0;
 573         entity->num_backlinks = 0;
 574
 575         if (!ida_pre_get(&mdev->entity_internal_idx, GFP_KERNEL))
 576                 return -ENOMEM;
 577
 578         mutex_lock(&mdev->graph_mutex);
 579
 580         ret = ida_get_new_above(&mdev->entity_internal_idx, 1,
 581                                 &entity->internal_idx);
 582         if (ret < 0) {
 583                 mutex_unlock(&mdev->graph_mutex);
 584                 return ret;
 585         }
 586
 587         mdev->entity_internal_idx_max =
 588                 max(mdev->entity_internal_idx_max, entity->internal_idx);
 589
 590         /* Initialize media_gobj embedded at the entity */
 591         media_gobj_create(mdev, MEDIA_GRAPH_ENTITY, &entity->graph_obj);
 592
 593         /* Initialize objects at the pads */
 594         for (i = 0; i < entity->num_pads; i++)
 595                 media_gobj_create(mdev, MEDIA_GRAPH_PAD,
 596                                &entity->pads[i].graph_obj);
 597
 598         /* invoke entity_notify callbacks */
 599         list_for_each_entry_safe(notify, next, &mdev->entity_notify, list) {
 600                 (notify)->notify(entity, notify->notify_data);
 601         }
 602
 603         if (mdev->entity_internal_idx_max
 604             >= mdev->pm_count_walk.ent_enum.idx_max) {
 605                 struct media_entity_graph new = { .top = 0 };
 606
 607                 /*
 608                  * Initialise the new graph walk before cleaning up
 609                  * the old one in order not to spoil the graph walk
 610                  * object of the media device if graph walk init fails.
 611                  */
 612                 ret = media_entity_graph_walk_init(&new, mdev);
 613                 if (ret) {
 614                         mutex_unlock(&mdev->graph_mutex);
 615                         return ret;
 616                 }
 617                 media_entity_graph_walk_cleanup(&mdev->pm_count_walk);
 618                 mdev->pm_count_walk = new;
 619         }
 620         mutex_unlock(&mdev->graph_mutex);
 621
 622         return 0;
 623 }
 624 EXPORT_SYMBOL_GPL(media_device_register_entity);
 625
 626 static void __media_device_unregister_entity(struct media_entity *entity)
 627 {
 628         struct media_device *mdev = entity->graph_obj.mdev;
 629         struct media_link *link, *tmp;
 630         struct media_interface *intf;
 631         unsigned int i;
 632
 633         ida_simple_remove(&mdev->entity_internal_idx, entity->internal_idx);
 634
 635         /* Remove all interface links pointing to this entity */
 636         list_for_each_entry(intf, &mdev->interfaces, graph_obj.list) {
 637                 list_for_each_entry_safe(link, tmp, &intf->links, list) {
 638                         if (link->entity == entity)
 639                                 __media_remove_intf_link(link);
 640                 }
 641         }
 642
 643         /* Remove all data links that belong to this entity */
 644         __media_entity_remove_links(entity);
 645
 646         /* Remove all pads that belong to this entity */
 647         for (i = 0; i < entity->num_pads; i++)
 648                 media_gobj_destroy(&entity->pads[i].graph_obj);
 649
 650         /* Remove the entity */
 651         media_gobj_destroy(&entity->graph_obj);
 652
 653         /* invoke entity_notify callbacks to handle entity removal?? */
 654
 655         entity->graph_obj.mdev = NULL;
 656 }
 657
 658 void media_device_unregister_entity(struct media_entity *entity)
 659 {
 660         struct media_device *mdev = entity->graph_obj.mdev;
 661
 662         if (mdev == NULL)
 663                 return;
 664
 665         mutex_lock(&mdev->graph_mutex);
 666         __media_device_unregister_entity(entity);
 667         mutex_unlock(&mdev->graph_mutex);
 668 }
 669 EXPORT_SYMBOL_GPL(media_device_unregister_entity);
 670
 671 /**
 672  * media_device_init() - initialize a media device
 673  * @mdev:       The media device
 674  *
 675  * The caller is responsible for initializing the media device before
 676  * registration. The following fields must be set:
 677  *
 678  * - dev must point to the parent device
 679  * - model must be filled with the device model name
 680  */
 681 void media_device_init(struct media_device *mdev)
 682 {
 683         INIT_LIST_HEAD(&mdev->entities);
 684         INIT_LIST_HEAD(&mdev->interfaces);
 685         INIT_LIST_HEAD(&mdev->pads);
 686         INIT_LIST_HEAD(&mdev->links);
 687         INIT_LIST_HEAD(&mdev->entity_notify);
 688         mutex_init(&mdev->graph_mutex);
 689         ida_init(&mdev->entity_internal_idx);
 690
 691         dev_dbg(mdev->dev, "Media device initialized\n");
 692 }
 693 EXPORT_SYMBOL_GPL(media_device_init);
 694
 695 void media_device_cleanup(struct media_device *mdev)
 696 {
 697         ida_destroy(&mdev->entity_internal_idx);
 698         mdev->entity_internal_idx_max = 0;
 699         media_entity_graph_walk_cleanup(&mdev->pm_count_walk);
 700         mutex_destroy(&mdev->graph_mutex);
 701 }
 702 EXPORT_SYMBOL_GPL(media_device_cleanup);
 703
 704 int __must_check __media_device_register(struct media_device *mdev,
 705                                          struct module *owner)
 706 {
 707         struct media_devnode *devnode;
 708         int ret;
 709
 710         devnode = kzalloc(sizeof(*devnode), GFP_KERNEL);
 711         if (!devnode)
 712                 return -ENOMEM;
 713
 714         /* Register the device node. */
 715         mdev->devnode = devnode;
 716         devnode->fops = &media_device_fops;
 717         devnode->parent = mdev->dev;
 718         devnode->release = media_device_release;
 719
 720         /* Set version 0 to indicate user-space that the graph is static */
 721         mdev->topology_version = 0;
 722
 723         ret = media_devnode_register(mdev, devnode, owner);
 724         if (ret < 0) {
 725                 /* devnode free is handled in media_devnode_*() */
 726                 mdev->devnode = NULL;
 727                 return ret;
 728         }
 729
 730         ret = device_create_file(&devnode->dev, &dev_attr_model);
 731         if (ret < 0) {
 732                 /* devnode free is handled in media_devnode_*() */
 733                 mdev->devnode = NULL;
 734                 media_devnode_unregister_prepare(devnode);
 735                 media_devnode_unregister(devnode);
 736                 return ret;
 737         }
 738
 739         dev_dbg(mdev->dev, "Media device registered\n");
 740
 741         return 0;
 742 }
 743 EXPORT_SYMBOL_GPL(__media_device_register);
 744
 745 int __must_check media_device_register_entity_notify(struct media_device *mdev,
 746                                         struct media_entity_notify *nptr)
 747 {
 748         mutex_lock(&mdev->graph_mutex);
 749         list_add_tail(&nptr->list, &mdev->entity_notify);
 750         mutex_unlock(&mdev->graph_mutex);
 751         return 0;
 752 }
 753 EXPORT_SYMBOL_GPL(media_device_register_entity_notify);
 754
 755 /*
 756  * Note: Should be called with mdev->lock held.
 757  */
 758 static void __media_device_unregister_entity_notify(struct media_device *mdev,
 759                                         struct media_entity_notify *nptr)
 760 {
 761         list_del(&nptr->list);
 762 }
 763
 764 void media_device_unregister_entity_notify(struct media_device *mdev,
 765                                         struct media_entity_notify *nptr)
 766 {
 767         mutex_lock(&mdev->graph_mutex);
 768         __media_device_unregister_entity_notify(mdev, nptr);
 769         mutex_unlock(&mdev->graph_mutex);
 770 }
 771 EXPORT_SYMBOL_GPL(media_device_unregister_entity_notify);
 772
 773 void media_device_unregister(struct media_device *mdev)
 774 {
 775         struct media_entity *entity;
 776         struct media_entity *next;
 777         struct media_interface *intf, *tmp_intf;
 778         struct media_entity_notify *notify, *nextp;
 779
 780         if (mdev == NULL)
 781                 return;
 782
 783         mutex_lock(&mdev->graph_mutex);
 784
 785         /* Check if mdev was ever registered at all */
 786         if (!media_devnode_is_registered(mdev->devnode)) {
 787                 mutex_unlock(&mdev->graph_mutex);
 788                 return;
 789         }
 790
 791         /* Clear the devnode register bit to avoid races with media dev open */
 792         media_devnode_unregister_prepare(mdev->devnode);
 793
 794         /* Remove all entities from the media device */
 795         list_for_each_entry_safe(entity, next, &mdev->entities, graph_obj.list)
 796                 __media_device_unregister_entity(entity);
 797
 798         /* Remove all entity_notify callbacks from the media device */
 799         list_for_each_entry_safe(notify, nextp, &mdev->entity_notify, list)
 800                 __media_device_unregister_entity_notify(mdev, notify);
 801
 802         /* Remove all interfaces from the media device */
 803         list_for_each_entry_safe(intf, tmp_intf, &mdev->interfaces,
 804                                  graph_obj.list) {
 805                 __media_remove_intf_links(intf);
 806                 media_gobj_destroy(&intf->graph_obj);
 807                 kfree(intf);
 808         }
 809
 810         mutex_unlock(&mdev->graph_mutex);
 811
 812         dev_dbg(mdev->dev, "Media device unregistered\n");
 813
 814         device_remove_file(&mdev->devnode->dev, &dev_attr_model);
 815         media_devnode_unregister(mdev->devnode);
 816         /* devnode free is handled in media_devnode_*() */
 817         mdev->devnode = NULL;
 818 }
 819 EXPORT_SYMBOL_GPL(media_device_unregister);
 820
 821 static void media_device_release_devres(struct device *dev, void *res)
 822 {
 823 }
 824
 825 struct media_device *media_device_get_devres(struct device *dev)
 826 {
 827         struct media_device *mdev;
 828
 829         mdev = devres_find(dev, media_device_release_devres, NULL, NULL);
 830         if (mdev)
 831                 return mdev;
 832
 833         mdev = devres_alloc(media_device_release_devres,
 834                                 sizeof(struct media_device), GFP_KERNEL);
 835         if (!mdev)
 836                 return NULL;
 837         return devres_get(dev, mdev, NULL, NULL);
 838 }
 839 EXPORT_SYMBOL_GPL(media_device_get_devres);
 840
 841 struct media_device *media_device_find_devres(struct device *dev)
 842 {
 843         return devres_find(dev, media_device_release_devres, NULL, NULL);
 844 }
 845 EXPORT_SYMBOL_GPL(media_device_find_devres);
 846
 847 #if IS_ENABLED(CONFIG_PCI)
 848 void media_device_pci_init(struct media_device *mdev,
 849                            struct pci_dev *pci_dev,
 850                            const char *name)
 851 {
 852         mdev->dev = &pci_dev->dev;
 853
 854         if (name)
 855                 strlcpy(mdev->model, name, sizeof(mdev->model));
 856         else
 857                 strlcpy(mdev->model, pci_name(pci_dev), sizeof(mdev->model));
 858
 859         sprintf(mdev->bus_info, "PCI:%s", pci_name(pci_dev));
 860
 861         mdev->hw_revision = (pci_dev->subsystem_vendor << 16)
 862                             | pci_dev->subsystem_device;
 863
 864         mdev->driver_version = LINUX_VERSION_CODE;
 865
 866         media_device_init(mdev);
 867 }
 868 EXPORT_SYMBOL_GPL(media_device_pci_init);
 869 #endif
 870
 871 #if IS_ENABLED(CONFIG_USB)
 872 void __media_device_usb_init(struct media_device *mdev,
 873                              struct usb_device *udev,
 874                              const char *board_name,
 875                              const char *driver_name)
 876 {
 877         mdev->dev = &udev->dev;
 878
 879         if (driver_name)
 880                 strlcpy(mdev->driver_name, driver_name,
 881                         sizeof(mdev->driver_name));
 882
 883         if (board_name)
 884                 strlcpy(mdev->model, board_name, sizeof(mdev->model));
 885         else if (udev->product)
 886                 strlcpy(mdev->model, udev->product, sizeof(mdev->model));
 887         else
 888                 strlcpy(mdev->model, "unknown model", sizeof(mdev->model));
 889         if (udev->serial)
 890                 strlcpy(mdev->serial, udev->serial, sizeof(mdev->serial));
 891         usb_make_path(udev, mdev->bus_info, sizeof(mdev->bus_info));
 892         mdev->hw_revision = le16_to_cpu(udev->descriptor.bcdDevice);
 893         mdev->driver_version = LINUX_VERSION_CODE;
 894
 895         media_device_init(mdev);
 896 }
 897 EXPORT_SYMBOL_GPL(__media_device_usb_init);
 898 #endif
 899
 900
 901 #endif /* CONFIG_MEDIA_CONTROLLER */