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