1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Media entity 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 #ifndef _MEDIA_ENTITY_H 12 #define _MEDIA_ENTITY_H 13 14 #include <linux/bitmap.h> 15 #include <linux/bug.h> 16 #include <linux/container_of.h> 17 #include <linux/fwnode.h> 18 #include <linux/list.h> 19 #include <linux/media.h> 20 #include <linux/minmax.h> 21 #include <linux/types.h> 22 23 /* Enums used internally at the media controller to represent graphs */ 24 25 /** 26 * enum media_gobj_type - type of a graph object 27 * 28 * @MEDIA_GRAPH_ENTITY: Identify a media entity 29 * @MEDIA_GRAPH_PAD: Identify a media pad 30 * @MEDIA_GRAPH_LINK: Identify a media link 31 * @MEDIA_GRAPH_INTF_DEVNODE: Identify a media Kernel API interface via 32 * a device node 33 */ 34 enum media_gobj_type { 35 MEDIA_GRAPH_ENTITY, 36 MEDIA_GRAPH_PAD, 37 MEDIA_GRAPH_LINK, 38 MEDIA_GRAPH_INTF_DEVNODE, 39 }; 40 41 #define MEDIA_BITS_PER_TYPE 8 42 #define MEDIA_BITS_PER_ID (32 - MEDIA_BITS_PER_TYPE) 43 #define MEDIA_ID_MASK GENMASK_ULL(MEDIA_BITS_PER_ID - 1, 0) 44 45 /* Structs to represent the objects that belong to a media graph */ 46 47 /** 48 * struct media_gobj - Define a graph object. 49 * 50 * @mdev: Pointer to the struct &media_device that owns the object 51 * @id: Non-zero object ID identifier. The ID should be unique 52 * inside a media_device, as it is composed by 53 * %MEDIA_BITS_PER_TYPE to store the type plus 54 * %MEDIA_BITS_PER_ID to store the ID 55 * @list: List entry stored in one of the per-type mdev object lists 56 * 57 * All objects on the media graph should have this struct embedded 58 */ 59 struct media_gobj { 60 struct media_device *mdev; 61 u32 id; 62 struct list_head list; 63 }; 64 65 #define MEDIA_ENTITY_ENUM_MAX_DEPTH 16 66 67 /** 68 * struct media_entity_enum - An enumeration of media entities. 69 * 70 * @bmap: Bit map in which each bit represents one entity at struct 71 * media_entity->internal_idx. 72 * @idx_max: Number of bits in bmap 73 */ 74 struct media_entity_enum { 75 unsigned long *bmap; 76 int idx_max; 77 }; 78 79 /** 80 * struct media_graph - Media graph traversal state 81 * 82 * @stack: Graph traversal stack; the stack contains information 83 * on the path the media entities to be walked and the 84 * links through which they were reached. 85 * @stack.entity: pointer to &struct media_entity at the graph. 86 * @stack.link: pointer to &struct list_head. 87 * @ent_enum: Visited entities 88 * @top: The top of the stack 89 */ 90 struct media_graph { 91 struct { 92 struct media_entity *entity; 93 struct list_head *link; 94 } stack[MEDIA_ENTITY_ENUM_MAX_DEPTH]; 95 96 struct media_entity_enum ent_enum; 97 int top; 98 }; 99 100 /** 101 * struct media_pipeline - Media pipeline related information 102 * 103 * @allocated: Media pipeline allocated and freed by the framework 104 * @mdev: The media device the pipeline is part of 105 * @pads: List of media_pipeline_pad 106 * @start_count: Media pipeline start - stop count 107 */ 108 struct media_pipeline { 109 bool allocated; 110 struct media_device *mdev; 111 struct list_head pads; 112 int start_count; 113 }; 114 115 /** 116 * struct media_pipeline_pad - A pad part of a media pipeline 117 * 118 * @list: Entry in the media_pad pads list 119 * @pipe: The media_pipeline that the pad is part of 120 * @pad: The media pad 121 * 122 * This structure associate a pad with a media pipeline. Instances of 123 * media_pipeline_pad are created by media_pipeline_start() when it builds the 124 * pipeline, and stored in the &media_pad.pads list. media_pipeline_stop() 125 * removes the entries from the list and deletes them. 126 */ 127 struct media_pipeline_pad { 128 struct list_head list; 129 struct media_pipeline *pipe; 130 struct media_pad *pad; 131 }; 132 133 /** 134 * struct media_pipeline_pad_iter - Iterator for media_pipeline_for_each_pad 135 * 136 * @cursor: The current element 137 */ 138 struct media_pipeline_pad_iter { 139 struct list_head *cursor; 140 }; 141 142 /** 143 * struct media_pipeline_entity_iter - Iterator for media_pipeline_for_each_entity 144 * 145 * @ent_enum: The entity enumeration tracker 146 * @cursor: The current element 147 */ 148 struct media_pipeline_entity_iter { 149 struct media_entity_enum ent_enum; 150 struct list_head *cursor; 151 }; 152 153 /** 154 * struct media_link - A link object part of a media graph. 155 * 156 * @graph_obj: Embedded structure containing the media object common data 157 * @list: Linked list associated with an entity or an interface that 158 * owns the link. 159 * @gobj0: Part of a union. Used to get the pointer for the first 160 * graph_object of the link. 161 * @source: Part of a union. Used only if the first object (gobj0) is 162 * a pad. In that case, it represents the source pad. 163 * @intf: Part of a union. Used only if the first object (gobj0) is 164 * an interface. 165 * @gobj1: Part of a union. Used to get the pointer for the second 166 * graph_object of the link. 167 * @sink: Part of a union. Used only if the second object (gobj1) is 168 * a pad. In that case, it represents the sink pad. 169 * @entity: Part of a union. Used only if the second object (gobj1) is 170 * an entity. 171 * @reverse: Pointer to the link for the reverse direction of a pad to pad 172 * link. 173 * @flags: Link flags, as defined in uapi/media.h (MEDIA_LNK_FL_*) 174 * @is_backlink: Indicate if the link is a backlink. 175 */ 176 struct media_link { 177 struct media_gobj graph_obj; 178 struct list_head list; 179 union { 180 struct media_gobj *gobj0; 181 struct media_pad *source; 182 struct media_interface *intf; 183 }; 184 union { 185 struct media_gobj *gobj1; 186 struct media_pad *sink; 187 struct media_entity *entity; 188 }; 189 struct media_link *reverse; 190 unsigned long flags; 191 bool is_backlink; 192 }; 193 194 /** 195 * enum media_pad_signal_type - type of the signal inside a media pad 196 * 197 * @PAD_SIGNAL_DEFAULT: 198 * Default signal. Use this when all inputs or all outputs are 199 * uniquely identified by the pad number. 200 * @PAD_SIGNAL_ANALOG: 201 * The pad contains an analog signal. It can be Radio Frequency, 202 * Intermediate Frequency, a baseband signal or sub-carriers. 203 * Tuner inputs, IF-PLL demodulators, composite and s-video signals 204 * should use it. 205 * @PAD_SIGNAL_DV: 206 * Contains a digital video signal, with can be a bitstream of samples 207 * taken from an analog TV video source. On such case, it usually 208 * contains the VBI data on it. 209 * @PAD_SIGNAL_AUDIO: 210 * Contains an Intermediate Frequency analog signal from an audio 211 * sub-carrier or an audio bitstream. IF signals are provided by tuners 212 * and consumed by audio AM/FM decoders. Bitstream audio is provided by 213 * an audio decoder. 214 */ 215 enum media_pad_signal_type { 216 PAD_SIGNAL_DEFAULT = 0, 217 PAD_SIGNAL_ANALOG, 218 PAD_SIGNAL_DV, 219 PAD_SIGNAL_AUDIO, 220 }; 221 222 /** 223 * struct media_pad - A media pad graph object. 224 * 225 * @graph_obj: Embedded structure containing the media object common data 226 * @entity: Entity this pad belongs to 227 * @index: Pad index in the entity pads array, numbered from 0 to n 228 * @num_links: Number of links connected to this pad 229 * @sig_type: Type of the signal inside a media pad 230 * @flags: Pad flags, as defined in 231 * :ref:`include/uapi/linux/media.h <media_header>` 232 * (seek for ``MEDIA_PAD_FL_*``) 233 * @pipe: Pipeline this pad belongs to. Use media_entity_pipeline() to 234 * access this field. 235 */ 236 struct media_pad { 237 struct media_gobj graph_obj; /* must be first field in struct */ 238 struct media_entity *entity; 239 u16 index; 240 u16 num_links; 241 enum media_pad_signal_type sig_type; 242 unsigned long flags; 243 244 /* 245 * The fields below are private, and should only be accessed via 246 * appropriate functions. 247 */ 248 struct media_pipeline *pipe; 249 }; 250 251 /** 252 * struct media_entity_operations - Media entity operations 253 * @get_fwnode_pad: Return the pad number based on a fwnode endpoint or 254 * a negative value on error. This operation can be used 255 * to map a fwnode to a media pad number. Optional. 256 * @link_setup: Notify the entity of link changes. The operation can 257 * return an error, in which case link setup will be 258 * cancelled. Optional. 259 * @link_validate: Return whether a link is valid from the entity point of 260 * view. The media_pipeline_start() function 261 * validates all links by calling this operation. Optional. 262 * @has_pad_interdep: Return whether two pads of the entity are 263 * interdependent. If two pads are interdependent they are 264 * part of the same pipeline and enabling one of the pads 265 * means that the other pad will become "locked" and 266 * doesn't allow configuration changes. pad0 and pad1 are 267 * guaranteed to not both be sinks or sources. Never call 268 * the .has_pad_interdep() operation directly, always use 269 * media_entity_has_pad_interdep(). 270 * Optional: If the operation isn't implemented all pads 271 * will be considered as interdependent. 272 * 273 * .. note:: 274 * 275 * Those these callbacks are called with struct &media_device.graph_mutex 276 * mutex held. 277 */ 278 struct media_entity_operations { 279 int (*get_fwnode_pad)(struct media_entity *entity, 280 struct fwnode_endpoint *endpoint); 281 int (*link_setup)(struct media_entity *entity, 282 const struct media_pad *local, 283 const struct media_pad *remote, u32 flags); 284 int (*link_validate)(struct media_link *link); 285 bool (*has_pad_interdep)(struct media_entity *entity, unsigned int pad0, 286 unsigned int pad1); 287 }; 288 289 /** 290 * enum media_entity_type - Media entity type 291 * 292 * @MEDIA_ENTITY_TYPE_BASE: 293 * The entity isn't embedded in another subsystem structure. 294 * @MEDIA_ENTITY_TYPE_VIDEO_DEVICE: 295 * The entity is embedded in a struct video_device instance. 296 * @MEDIA_ENTITY_TYPE_V4L2_SUBDEV: 297 * The entity is embedded in a struct v4l2_subdev instance. 298 * 299 * Media entity objects are often not instantiated directly, but the media 300 * entity structure is inherited by (through embedding) other subsystem-specific 301 * structures. The media entity type identifies the type of the subclass 302 * structure that implements a media entity instance. 303 * 304 * This allows runtime type identification of media entities and safe casting to 305 * the correct object type. For instance, a media entity structure instance 306 * embedded in a v4l2_subdev structure instance will have the type 307 * %MEDIA_ENTITY_TYPE_V4L2_SUBDEV and can safely be cast to a &v4l2_subdev 308 * structure using the container_of() macro. 309 */ 310 enum media_entity_type { 311 MEDIA_ENTITY_TYPE_BASE, 312 MEDIA_ENTITY_TYPE_VIDEO_DEVICE, 313 MEDIA_ENTITY_TYPE_V4L2_SUBDEV, 314 }; 315 316 /** 317 * struct media_entity - A media entity graph object. 318 * 319 * @graph_obj: Embedded structure containing the media object common data. 320 * @name: Entity name. 321 * @obj_type: Type of the object that implements the media_entity. 322 * @function: Entity main function, as defined in 323 * :ref:`include/uapi/linux/media.h <media_header>` 324 * (seek for ``MEDIA_ENT_F_*``) 325 * @flags: Entity flags, as defined in 326 * :ref:`include/uapi/linux/media.h <media_header>` 327 * (seek for ``MEDIA_ENT_FL_*``) 328 * @num_pads: Number of sink and source pads. 329 * @num_links: Total number of links, forward and back, enabled and disabled. 330 * @num_backlinks: Number of backlinks 331 * @internal_idx: An unique internal entity specific number. The numbers are 332 * re-used if entities are unregistered or registered again. 333 * @pads: Pads array with the size defined by @num_pads. 334 * @links: List of data links. 335 * @ops: Entity operations. 336 * @use_count: Use count for the entity. 337 * @info: Union with devnode information. Kept just for backward 338 * compatibility. 339 * @info.dev: Contains device major and minor info. 340 * @info.dev.major: device node major, if the device is a devnode. 341 * @info.dev.minor: device node minor, if the device is a devnode. 342 * 343 * .. note:: 344 * 345 * The @use_count reference count must never be negative, but is a signed 346 * integer on purpose: a simple ``WARN_ON(<0)`` check can be used to detect 347 * reference count bugs that would make it negative. 348 */ 349 struct media_entity { 350 struct media_gobj graph_obj; /* must be first field in struct */ 351 const char *name; 352 enum media_entity_type obj_type; 353 u32 function; 354 unsigned long flags; 355 356 u16 num_pads; 357 u16 num_links; 358 u16 num_backlinks; 359 int internal_idx; 360 361 struct media_pad *pads; 362 struct list_head links; 363 364 const struct media_entity_operations *ops; 365 366 int use_count; 367 368 union { 369 struct { 370 u32 major; 371 u32 minor; 372 } dev; 373 } info; 374 }; 375 376 /** 377 * media_entity_for_each_pad - Iterate on all pads in an entity 378 * @entity: The entity the pads belong to 379 * @iter: The iterator pad 380 * 381 * Iterate on all pads in a media entity. 382 */ 383 #define media_entity_for_each_pad(entity, iter) \ 384 for (iter = (entity)->pads; \ 385 iter < &(entity)->pads[(entity)->num_pads]; \ 386 ++iter) 387 388 /** 389 * struct media_interface - A media interface graph object. 390 * 391 * @graph_obj: embedded graph object 392 * @links: List of links pointing to graph entities 393 * @type: Type of the interface as defined in 394 * :ref:`include/uapi/linux/media.h <media_header>` 395 * (seek for ``MEDIA_INTF_T_*``) 396 * @flags: Interface flags as defined in 397 * :ref:`include/uapi/linux/media.h <media_header>` 398 * (seek for ``MEDIA_INTF_FL_*``) 399 * 400 * .. note:: 401 * 402 * Currently, no flags for &media_interface is defined. 403 */ 404 struct media_interface { 405 struct media_gobj graph_obj; 406 struct list_head links; 407 u32 type; 408 u32 flags; 409 }; 410 411 /** 412 * struct media_intf_devnode - A media interface via a device node. 413 * 414 * @intf: embedded interface object 415 * @major: Major number of a device node 416 * @minor: Minor number of a device node 417 */ 418 struct media_intf_devnode { 419 struct media_interface intf; 420 421 /* Should match the fields at media_v2_intf_devnode */ 422 u32 major; 423 u32 minor; 424 }; 425 426 /** 427 * media_entity_id() - return the media entity graph object id 428 * 429 * @entity: pointer to &media_entity 430 */ 431 static inline u32 media_entity_id(struct media_entity *entity) 432 { 433 return entity->graph_obj.id; 434 } 435 436 /** 437 * media_type() - return the media object type 438 * 439 * @gobj: Pointer to the struct &media_gobj graph object 440 */ 441 static inline enum media_gobj_type media_type(struct media_gobj *gobj) 442 { 443 return gobj->id >> MEDIA_BITS_PER_ID; 444 } 445 446 /** 447 * media_id() - return the media object ID 448 * 449 * @gobj: Pointer to the struct &media_gobj graph object 450 */ 451 static inline u32 media_id(struct media_gobj *gobj) 452 { 453 return gobj->id & MEDIA_ID_MASK; 454 } 455 456 /** 457 * media_gobj_gen_id() - encapsulates type and ID on at the object ID 458 * 459 * @type: object type as define at enum &media_gobj_type. 460 * @local_id: next ID, from struct &media_device.id. 461 */ 462 static inline u32 media_gobj_gen_id(enum media_gobj_type type, u64 local_id) 463 { 464 u32 id; 465 466 id = type << MEDIA_BITS_PER_ID; 467 id |= local_id & MEDIA_ID_MASK; 468 469 return id; 470 } 471 472 /** 473 * is_media_entity_v4l2_video_device() - Check if the entity is a video_device 474 * @entity: pointer to entity 475 * 476 * Return: %true if the entity is an instance of a video_device object and can 477 * safely be cast to a struct video_device using the container_of() macro, or 478 * %false otherwise. 479 */ 480 static inline bool is_media_entity_v4l2_video_device(struct media_entity *entity) 481 { 482 return entity && entity->obj_type == MEDIA_ENTITY_TYPE_VIDEO_DEVICE; 483 } 484 485 /** 486 * is_media_entity_v4l2_subdev() - Check if the entity is a v4l2_subdev 487 * @entity: pointer to entity 488 * 489 * Return: %true if the entity is an instance of a &v4l2_subdev object and can 490 * safely be cast to a struct &v4l2_subdev using the container_of() macro, or 491 * %false otherwise. 492 */ 493 static inline bool is_media_entity_v4l2_subdev(struct media_entity *entity) 494 { 495 return entity && entity->obj_type == MEDIA_ENTITY_TYPE_V4L2_SUBDEV; 496 } 497 498 /** 499 * media_entity_enum_init - Initialise an entity enumeration 500 * 501 * @ent_enum: Entity enumeration to be initialised 502 * @mdev: The related media device 503 * 504 * Return: zero on success or a negative error code. 505 */ 506 __must_check int media_entity_enum_init(struct media_entity_enum *ent_enum, 507 struct media_device *mdev); 508 509 /** 510 * media_entity_enum_cleanup - Release resources of an entity enumeration 511 * 512 * @ent_enum: Entity enumeration to be released 513 */ 514 void media_entity_enum_cleanup(struct media_entity_enum *ent_enum); 515 516 /** 517 * media_entity_enum_zero - Clear the entire enum 518 * 519 * @ent_enum: Entity enumeration to be cleared 520 */ 521 static inline void media_entity_enum_zero(struct media_entity_enum *ent_enum) 522 { 523 bitmap_zero(ent_enum->bmap, ent_enum->idx_max); 524 } 525 526 /** 527 * media_entity_enum_set - Mark a single entity in the enum 528 * 529 * @ent_enum: Entity enumeration 530 * @entity: Entity to be marked 531 */ 532 static inline void media_entity_enum_set(struct media_entity_enum *ent_enum, 533 struct media_entity *entity) 534 { 535 if (WARN_ON(entity->internal_idx >= ent_enum->idx_max)) 536 return; 537 538 __set_bit(entity->internal_idx, ent_enum->bmap); 539 } 540 541 /** 542 * media_entity_enum_clear - Unmark a single entity in the enum 543 * 544 * @ent_enum: Entity enumeration 545 * @entity: Entity to be unmarked 546 */ 547 static inline void media_entity_enum_clear(struct media_entity_enum *ent_enum, 548 struct media_entity *entity) 549 { 550 if (WARN_ON(entity->internal_idx >= ent_enum->idx_max)) 551 return; 552 553 __clear_bit(entity->internal_idx, ent_enum->bmap); 554 } 555 556 /** 557 * media_entity_enum_test - Test whether the entity is marked 558 * 559 * @ent_enum: Entity enumeration 560 * @entity: Entity to be tested 561 * 562 * Returns %true if the entity was marked. 563 */ 564 static inline bool media_entity_enum_test(struct media_entity_enum *ent_enum, 565 struct media_entity *entity) 566 { 567 if (WARN_ON(entity->internal_idx >= ent_enum->idx_max)) 568 return true; 569 570 return test_bit(entity->internal_idx, ent_enum->bmap); 571 } 572 573 /** 574 * media_entity_enum_test_and_set - Test whether the entity is marked, 575 * and mark it 576 * 577 * @ent_enum: Entity enumeration 578 * @entity: Entity to be tested 579 * 580 * Returns %true if the entity was marked, and mark it before doing so. 581 */ 582 static inline bool 583 media_entity_enum_test_and_set(struct media_entity_enum *ent_enum, 584 struct media_entity *entity) 585 { 586 if (WARN_ON(entity->internal_idx >= ent_enum->idx_max)) 587 return true; 588 589 return __test_and_set_bit(entity->internal_idx, ent_enum->bmap); 590 } 591 592 /** 593 * media_entity_enum_empty - Test whether the entire enum is empty 594 * 595 * @ent_enum: Entity enumeration 596 * 597 * Return: %true if the entity was empty. 598 */ 599 static inline bool media_entity_enum_empty(struct media_entity_enum *ent_enum) 600 { 601 return bitmap_empty(ent_enum->bmap, ent_enum->idx_max); 602 } 603 604 /** 605 * media_entity_enum_intersects - Test whether two enums intersect 606 * 607 * @ent_enum1: First entity enumeration 608 * @ent_enum2: Second entity enumeration 609 * 610 * Return: %true if entity enumerations @ent_enum1 and @ent_enum2 intersect, 611 * otherwise %false. 612 */ 613 static inline bool media_entity_enum_intersects( 614 struct media_entity_enum *ent_enum1, 615 struct media_entity_enum *ent_enum2) 616 { 617 WARN_ON(ent_enum1->idx_max != ent_enum2->idx_max); 618 619 return bitmap_intersects(ent_enum1->bmap, ent_enum2->bmap, 620 min(ent_enum1->idx_max, ent_enum2->idx_max)); 621 } 622 623 /** 624 * gobj_to_entity - returns the struct &media_entity pointer from the 625 * @gobj contained on it. 626 * 627 * @gobj: Pointer to the struct &media_gobj graph object 628 */ 629 #define gobj_to_entity(gobj) \ 630 container_of_const(gobj, struct media_entity, graph_obj) 631 632 /** 633 * gobj_to_pad - returns the struct &media_pad pointer from the 634 * @gobj contained on it. 635 * 636 * @gobj: Pointer to the struct &media_gobj graph object 637 */ 638 #define gobj_to_pad(gobj) \ 639 container_of_const(gobj, struct media_pad, graph_obj) 640 641 /** 642 * gobj_to_link - returns the struct &media_link pointer from the 643 * @gobj contained on it. 644 * 645 * @gobj: Pointer to the struct &media_gobj graph object 646 */ 647 #define gobj_to_link(gobj) \ 648 container_of_const(gobj, struct media_link, graph_obj) 649 650 /** 651 * gobj_to_intf - returns the struct &media_interface pointer from the 652 * @gobj contained on it. 653 * 654 * @gobj: Pointer to the struct &media_gobj graph object 655 */ 656 #define gobj_to_intf(gobj) \ 657 container_of_const(gobj, struct media_interface, graph_obj) 658 659 /** 660 * intf_to_devnode - returns the struct media_intf_devnode pointer from the 661 * @intf contained on it. 662 * 663 * @intf: Pointer to struct &media_intf_devnode 664 */ 665 #define intf_to_devnode(intf) \ 666 container_of_const(intf, struct media_intf_devnode, intf) 667 668 /** 669 * media_gobj_create - Initialize a graph object 670 * 671 * @mdev: Pointer to the &media_device that contains the object 672 * @type: Type of the object 673 * @gobj: Pointer to the struct &media_gobj graph object 674 * 675 * This routine initializes the embedded struct &media_gobj inside a 676 * media graph object. It is called automatically if ``media_*_create`` 677 * function calls are used. However, if the object (entity, link, pad, 678 * interface) is embedded on some other object, this function should be 679 * called before registering the object at the media controller. 680 */ 681 void media_gobj_create(struct media_device *mdev, 682 enum media_gobj_type type, 683 struct media_gobj *gobj); 684 685 /** 686 * media_gobj_destroy - Stop using a graph object on a media device 687 * 688 * @gobj: Pointer to the struct &media_gobj graph object 689 * 690 * This should be called by all routines like media_device_unregister() 691 * that remove/destroy media graph objects. 692 */ 693 void media_gobj_destroy(struct media_gobj *gobj); 694 695 /** 696 * media_entity_pads_init() - Initialize the entity pads 697 * 698 * @entity: entity where the pads belong 699 * @num_pads: total number of sink and source pads 700 * @pads: Array of @num_pads pads. 701 * 702 * The pads array is managed by the entity driver and passed to 703 * media_entity_pads_init() where its pointer will be stored in the 704 * &media_entity structure. 705 * 706 * If no pads are needed, drivers could either directly fill 707 * &media_entity->num_pads with 0 and &media_entity->pads with %NULL or call 708 * this function that will do the same. 709 * 710 * As the number of pads is known in advance, the pads array is not allocated 711 * dynamically but is managed by the entity driver. Most drivers will embed the 712 * pads array in a driver-specific structure, avoiding dynamic allocation. 713 * 714 * Drivers must set the direction of every pad in the pads array before calling 715 * media_entity_pads_init(). The function will initialize the other pads fields. 716 */ 717 int media_entity_pads_init(struct media_entity *entity, u16 num_pads, 718 struct media_pad *pads); 719 720 /** 721 * media_entity_cleanup() - free resources associated with an entity 722 * 723 * @entity: entity where the pads belong 724 * 725 * This function must be called during the cleanup phase after unregistering 726 * the entity (currently, it does nothing). 727 * 728 * Calling media_entity_cleanup() on a media_entity whose memory has been 729 * zeroed but that has not been initialized with media_entity_pads_init() is 730 * valid and is a no-op. 731 */ 732 static inline void media_entity_cleanup(struct media_entity *entity) 733 { 734 } 735 736 /** 737 * media_get_pad_index() - retrieves a pad index from an entity 738 * 739 * @entity: entity where the pads belong 740 * @pad_type: the type of the pad, one of MEDIA_PAD_FL_* pad types 741 * @sig_type: type of signal of the pad to be search 742 * 743 * This helper function finds the first pad index inside an entity that 744 * satisfies both @is_sink and @sig_type conditions. 745 * 746 * Return: 747 * 748 * On success, return the pad number. If the pad was not found or the media 749 * entity is a NULL pointer, return -EINVAL. 750 */ 751 int media_get_pad_index(struct media_entity *entity, u32 pad_type, 752 enum media_pad_signal_type sig_type); 753 754 /** 755 * media_create_pad_link() - creates a link between two entities. 756 * 757 * @source: pointer to &media_entity of the source pad. 758 * @source_pad: number of the source pad in the pads array 759 * @sink: pointer to &media_entity of the sink pad. 760 * @sink_pad: number of the sink pad in the pads array. 761 * @flags: Link flags, as defined in 762 * :ref:`include/uapi/linux/media.h <media_header>` 763 * ( seek for ``MEDIA_LNK_FL_*``) 764 * 765 * Valid values for flags: 766 * 767 * %MEDIA_LNK_FL_ENABLED 768 * Indicates that the link is enabled and can be used to transfer media data. 769 * When two or more links target a sink pad, only one of them can be 770 * enabled at a time. 771 * 772 * %MEDIA_LNK_FL_IMMUTABLE 773 * Indicates that the link enabled state can't be modified at runtime. If 774 * %MEDIA_LNK_FL_IMMUTABLE is set, then %MEDIA_LNK_FL_ENABLED must also be 775 * set, since an immutable link is always enabled. 776 * 777 * .. note:: 778 * 779 * Before calling this function, media_entity_pads_init() and 780 * media_device_register_entity() should be called previously for both ends. 781 */ 782 __must_check int media_create_pad_link(struct media_entity *source, 783 u16 source_pad, struct media_entity *sink, 784 u16 sink_pad, u32 flags); 785 786 /** 787 * media_create_pad_links() - creates a link between two entities. 788 * 789 * @mdev: Pointer to the media_device that contains the object 790 * @source_function: Function of the source entities. Used only if @source is 791 * NULL. 792 * @source: pointer to &media_entity of the source pad. If NULL, it will use 793 * all entities that matches the @sink_function. 794 * @source_pad: number of the source pad in the pads array 795 * @sink_function: Function of the sink entities. Used only if @sink is NULL. 796 * @sink: pointer to &media_entity of the sink pad. If NULL, it will use 797 * all entities that matches the @sink_function. 798 * @sink_pad: number of the sink pad in the pads array. 799 * @flags: Link flags, as defined in include/uapi/linux/media.h. 800 * @allow_both_undefined: if %true, then both @source and @sink can be NULL. 801 * In such case, it will create a crossbar between all entities that 802 * matches @source_function to all entities that matches @sink_function. 803 * If %false, it will return 0 and won't create any link if both @source 804 * and @sink are NULL. 805 * 806 * Valid values for flags: 807 * 808 * A %MEDIA_LNK_FL_ENABLED flag indicates that the link is enabled and can be 809 * used to transfer media data. If multiple links are created and this 810 * flag is passed as an argument, only the first created link will have 811 * this flag. 812 * 813 * A %MEDIA_LNK_FL_IMMUTABLE flag indicates that the link enabled state can't 814 * be modified at runtime. If %MEDIA_LNK_FL_IMMUTABLE is set, then 815 * %MEDIA_LNK_FL_ENABLED must also be set since an immutable link is 816 * always enabled. 817 * 818 * It is common for some devices to have multiple source and/or sink entities 819 * of the same type that should be linked. While media_create_pad_link() 820 * creates link by link, this function is meant to allow 1:n, n:1 and even 821 * cross-bar (n:n) links. 822 * 823 * .. note:: 824 * 825 * Before calling this function, media_entity_pads_init() and 826 * media_device_register_entity() should be called previously for the 827 * entities to be linked. 828 */ 829 int media_create_pad_links(const struct media_device *mdev, 830 const u32 source_function, 831 struct media_entity *source, 832 const u16 source_pad, 833 const u32 sink_function, 834 struct media_entity *sink, 835 const u16 sink_pad, 836 u32 flags, 837 const bool allow_both_undefined); 838 839 void __media_entity_remove_links(struct media_entity *entity); 840 841 /** 842 * media_entity_remove_links() - remove all links associated with an entity 843 * 844 * @entity: pointer to &media_entity 845 * 846 * .. note:: 847 * 848 * This is called automatically when an entity is unregistered via 849 * media_device_register_entity(). 850 */ 851 void media_entity_remove_links(struct media_entity *entity); 852 853 /** 854 * __media_entity_setup_link - Configure a media link without locking 855 * @link: The link being configured 856 * @flags: Link configuration flags 857 * 858 * The bulk of link setup is handled by the two entities connected through the 859 * link. This function notifies both entities of the link configuration change. 860 * 861 * If the link is immutable or if the current and new configuration are 862 * identical, return immediately. 863 * 864 * The user is expected to hold link->source->parent->mutex. If not, 865 * media_entity_setup_link() should be used instead. 866 */ 867 int __media_entity_setup_link(struct media_link *link, u32 flags); 868 869 /** 870 * media_entity_setup_link() - changes the link flags properties in runtime 871 * 872 * @link: pointer to &media_link 873 * @flags: the requested new link flags 874 * 875 * The only configurable property is the %MEDIA_LNK_FL_ENABLED link flag 876 * to enable/disable a link. Links marked with the 877 * %MEDIA_LNK_FL_IMMUTABLE link flag can not be enabled or disabled. 878 * 879 * When a link is enabled or disabled, the media framework calls the 880 * link_setup operation for the two entities at the source and sink of the 881 * link, in that order. If the second link_setup call fails, another 882 * link_setup call is made on the first entity to restore the original link 883 * flags. 884 * 885 * Media device drivers can be notified of link setup operations by setting the 886 * &media_device.link_notify pointer to a callback function. If provided, the 887 * notification callback will be called before enabling and after disabling 888 * links. 889 * 890 * Entity drivers must implement the link_setup operation if any of their links 891 * is non-immutable. The operation must either configure the hardware or store 892 * the configuration information to be applied later. 893 * 894 * Link configuration must not have any side effect on other links. If an 895 * enabled link at a sink pad prevents another link at the same pad from 896 * being enabled, the link_setup operation must return %-EBUSY and can't 897 * implicitly disable the first enabled link. 898 * 899 * .. note:: 900 * 901 * The valid values of the flags for the link is the same as described 902 * on media_create_pad_link(), for pad to pad links or the same as described 903 * on media_create_intf_link(), for interface to entity links. 904 */ 905 int media_entity_setup_link(struct media_link *link, u32 flags); 906 907 /** 908 * media_entity_find_link - Find a link between two pads 909 * @source: Source pad 910 * @sink: Sink pad 911 * 912 * Return: returns a pointer to the link between the two entities. If no 913 * such link exists, return %NULL. 914 */ 915 struct media_link *media_entity_find_link(struct media_pad *source, 916 struct media_pad *sink); 917 918 /** 919 * media_pad_remote_pad_first - Find the first pad at the remote end of a link 920 * @pad: Pad at the local end of the link 921 * 922 * Search for a remote pad connected to the given pad by iterating over all 923 * links originating or terminating at that pad until an enabled link is found. 924 * 925 * Return: returns a pointer to the pad at the remote end of the first found 926 * enabled link, or %NULL if no enabled link has been found. 927 */ 928 struct media_pad *media_pad_remote_pad_first(const struct media_pad *pad); 929 930 /** 931 * media_pad_remote_pad_unique - Find a remote pad connected to a pad 932 * @pad: The pad 933 * 934 * Search for and return a remote pad connected to @pad through an enabled 935 * link. If multiple (or no) remote pads are found, an error is returned. 936 * 937 * The uniqueness constraint makes this helper function suitable for entities 938 * that support a single active source at a time on a given pad. 939 * 940 * Return: A pointer to the remote pad, or one of the following error pointers 941 * if an error occurs: 942 * 943 * * -ENOTUNIQ - Multiple links are enabled 944 * * -ENOLINK - No connected pad found 945 */ 946 struct media_pad *media_pad_remote_pad_unique(const struct media_pad *pad); 947 948 /** 949 * media_entity_remote_pad_unique - Find a remote pad connected to an entity 950 * @entity: The entity 951 * @type: The type of pad to find (MEDIA_PAD_FL_SINK or MEDIA_PAD_FL_SOURCE) 952 * 953 * Search for and return a remote pad of @type connected to @entity through an 954 * enabled link. If multiple (or no) remote pads match these criteria, an error 955 * is returned. 956 * 957 * The uniqueness constraint makes this helper function suitable for entities 958 * that support a single active source or sink at a time. 959 * 960 * Return: A pointer to the remote pad, or one of the following error pointers 961 * if an error occurs: 962 * 963 * * -ENOTUNIQ - Multiple links are enabled 964 * * -ENOLINK - No connected pad found 965 */ 966 struct media_pad * 967 media_entity_remote_pad_unique(const struct media_entity *entity, 968 unsigned int type); 969 970 /** 971 * media_entity_remote_source_pad_unique - Find a remote source pad connected to 972 * an entity 973 * @entity: The entity 974 * 975 * Search for and return a remote source pad connected to @entity through an 976 * enabled link. If multiple (or no) remote pads match these criteria, an error 977 * is returned. 978 * 979 * The uniqueness constraint makes this helper function suitable for entities 980 * that support a single active source at a time. 981 * 982 * Return: A pointer to the remote pad, or one of the following error pointers 983 * if an error occurs: 984 * 985 * * -ENOTUNIQ - Multiple links are enabled 986 * * -ENOLINK - No connected pad found 987 */ 988 static inline struct media_pad * 989 media_entity_remote_source_pad_unique(const struct media_entity *entity) 990 { 991 return media_entity_remote_pad_unique(entity, MEDIA_PAD_FL_SOURCE); 992 } 993 994 /** 995 * media_pad_is_streaming - Test if a pad is part of a streaming pipeline 996 * @pad: The pad 997 * 998 * Return: True if the pad is part of a pipeline started with the 999 * media_pipeline_start() function, false otherwise. 1000 */ 1001 static inline bool media_pad_is_streaming(const struct media_pad *pad) 1002 { 1003 return pad->pipe; 1004 } 1005 1006 /** 1007 * media_entity_is_streaming - Test if an entity is part of a streaming pipeline 1008 * @entity: The entity 1009 * 1010 * Return: True if the entity is part of a pipeline started with the 1011 * media_pipeline_start() function, false otherwise. 1012 */ 1013 static inline bool media_entity_is_streaming(const struct media_entity *entity) 1014 { 1015 struct media_pad *pad; 1016 1017 media_entity_for_each_pad(entity, pad) { 1018 if (media_pad_is_streaming(pad)) 1019 return true; 1020 } 1021 1022 return false; 1023 } 1024 1025 /** 1026 * media_entity_pipeline - Get the media pipeline an entity is part of 1027 * @entity: The entity 1028 * 1029 * DEPRECATED: use media_pad_pipeline() instead. 1030 * 1031 * This function returns the media pipeline that an entity has been associated 1032 * with when constructing the pipeline with media_pipeline_start(). The pointer 1033 * remains valid until media_pipeline_stop() is called. 1034 * 1035 * In general, entities can be part of multiple pipelines, when carrying 1036 * multiple streams (either on different pads, or on the same pad using 1037 * multiplexed streams). This function is to be used only for entities that 1038 * do not support multiple pipelines. 1039 * 1040 * Return: The media_pipeline the entity is part of, or NULL if the entity is 1041 * not part of any pipeline. 1042 */ 1043 struct media_pipeline *media_entity_pipeline(struct media_entity *entity); 1044 1045 /** 1046 * media_pad_pipeline - Get the media pipeline a pad is part of 1047 * @pad: The pad 1048 * 1049 * This function returns the media pipeline that a pad has been associated 1050 * with when constructing the pipeline with media_pipeline_start(). The pointer 1051 * remains valid until media_pipeline_stop() is called. 1052 * 1053 * Return: The media_pipeline the pad is part of, or NULL if the pad is 1054 * not part of any pipeline. 1055 */ 1056 struct media_pipeline *media_pad_pipeline(struct media_pad *pad); 1057 1058 /** 1059 * media_entity_get_fwnode_pad - Get pad number from fwnode 1060 * 1061 * @entity: The entity 1062 * @fwnode: Pointer to the fwnode_handle which should be used to find the pad 1063 * @direction_flags: Expected direction of the pad, as defined in 1064 * :ref:`include/uapi/linux/media.h <media_header>` 1065 * (seek for ``MEDIA_PAD_FL_*``) 1066 * 1067 * This function can be used to resolve the media pad number from 1068 * a fwnode. This is useful for devices which use more complex 1069 * mappings of media pads. 1070 * 1071 * If the entity does not implement the get_fwnode_pad() operation 1072 * then this function searches the entity for the first pad that 1073 * matches the @direction_flags. 1074 * 1075 * Return: returns the pad number on success or a negative error code. 1076 */ 1077 int media_entity_get_fwnode_pad(struct media_entity *entity, 1078 const struct fwnode_handle *fwnode, 1079 unsigned long direction_flags); 1080 1081 /** 1082 * media_graph_walk_init - Allocate resources used by graph walk. 1083 * 1084 * @graph: Media graph structure that will be used to walk the graph 1085 * @mdev: Pointer to the &media_device that contains the object 1086 * 1087 * This function is deprecated, use media_pipeline_for_each_pad() instead. 1088 * 1089 * The caller is required to hold the media_device graph_mutex during the graph 1090 * walk until the graph state is released. 1091 * 1092 * Returns zero on success or a negative error code otherwise. 1093 */ 1094 __must_check int media_graph_walk_init( 1095 struct media_graph *graph, struct media_device *mdev); 1096 1097 /** 1098 * media_graph_walk_cleanup - Release resources used by graph walk. 1099 * 1100 * @graph: Media graph structure that will be used to walk the graph 1101 * 1102 * This function is deprecated, use media_pipeline_for_each_pad() instead. 1103 */ 1104 void media_graph_walk_cleanup(struct media_graph *graph); 1105 1106 /** 1107 * media_graph_walk_start - Start walking the media graph at a 1108 * given entity 1109 * 1110 * @graph: Media graph structure that will be used to walk the graph 1111 * @entity: Starting entity 1112 * 1113 * This function is deprecated, use media_pipeline_for_each_pad() instead. 1114 * 1115 * Before using this function, media_graph_walk_init() must be 1116 * used to allocate resources used for walking the graph. This 1117 * function initializes the graph traversal structure to walk the 1118 * entities graph starting at the given entity. The traversal 1119 * structure must not be modified by the caller during graph 1120 * traversal. After the graph walk, the resources must be released 1121 * using media_graph_walk_cleanup(). 1122 */ 1123 void media_graph_walk_start(struct media_graph *graph, 1124 struct media_entity *entity); 1125 1126 /** 1127 * media_graph_walk_next - Get the next entity in the graph 1128 * @graph: Media graph structure 1129 * 1130 * This function is deprecated, use media_pipeline_for_each_pad() instead. 1131 * 1132 * Perform a depth-first traversal of the given media entities graph. 1133 * 1134 * The graph structure must have been previously initialized with a call to 1135 * media_graph_walk_start(). 1136 * 1137 * Return: returns the next entity in the graph or %NULL if the whole graph 1138 * have been traversed. 1139 */ 1140 struct media_entity *media_graph_walk_next(struct media_graph *graph); 1141 1142 /** 1143 * media_pipeline_start - Mark a pipeline as streaming 1144 * @origin: Starting pad 1145 * @pipe: Media pipeline to be assigned to all pads in the pipeline. 1146 * 1147 * Mark all pads connected to pad @origin through enabled links, either 1148 * directly or indirectly, as streaming. The given pipeline object is assigned 1149 * to every pad in the pipeline and stored in the media_pad pipe field. 1150 * 1151 * Calls to this function can be nested, in which case the same number of 1152 * media_pipeline_stop() calls will be required to stop streaming. The 1153 * pipeline pointer must be identical for all nested calls to 1154 * media_pipeline_start(). 1155 */ 1156 __must_check int media_pipeline_start(struct media_pad *origin, 1157 struct media_pipeline *pipe); 1158 /** 1159 * __media_pipeline_start - Mark a pipeline as streaming 1160 * 1161 * @origin: Starting pad 1162 * @pipe: Media pipeline to be assigned to all pads in the pipeline. 1163 * 1164 * ..note:: This is the non-locking version of media_pipeline_start() 1165 */ 1166 __must_check int __media_pipeline_start(struct media_pad *origin, 1167 struct media_pipeline *pipe); 1168 1169 /** 1170 * media_pipeline_stop - Mark a pipeline as not streaming 1171 * @pad: Starting pad 1172 * 1173 * Mark all pads connected to a given pad through enabled links, either 1174 * directly or indirectly, as not streaming. The media_pad pipe field is 1175 * reset to %NULL. 1176 * 1177 * If multiple calls to media_pipeline_start() have been made, the same 1178 * number of calls to this function are required to mark the pipeline as not 1179 * streaming. 1180 */ 1181 void media_pipeline_stop(struct media_pad *pad); 1182 1183 /** 1184 * __media_pipeline_stop - Mark a pipeline as not streaming 1185 * 1186 * @pad: Starting pad 1187 * 1188 * .. note:: This is the non-locking version of media_pipeline_stop() 1189 */ 1190 void __media_pipeline_stop(struct media_pad *pad); 1191 1192 struct media_pad * 1193 __media_pipeline_pad_iter_next(struct media_pipeline *pipe, 1194 struct media_pipeline_pad_iter *iter, 1195 struct media_pad *pad); 1196 1197 /** 1198 * media_pipeline_for_each_pad - Iterate on all pads in a media pipeline 1199 * @pipe: The pipeline 1200 * @iter: The iterator (struct media_pipeline_pad_iter) 1201 * @pad: The iterator pad 1202 * 1203 * Iterate on all pads in a media pipeline. This is only valid after the 1204 * pipeline has been built with media_pipeline_start() and before it gets 1205 * destroyed with media_pipeline_stop(). 1206 */ 1207 #define media_pipeline_for_each_pad(pipe, iter, pad) \ 1208 for (pad = __media_pipeline_pad_iter_next((pipe), iter, NULL); \ 1209 pad != NULL; \ 1210 pad = __media_pipeline_pad_iter_next((pipe), iter, pad)) 1211 1212 /** 1213 * media_pipeline_entity_iter_init - Initialize a pipeline entity iterator 1214 * @pipe: The pipeline 1215 * @iter: The iterator 1216 * 1217 * This function must be called to initialize the iterator before using it in a 1218 * media_pipeline_for_each_entity() loop. The iterator must be destroyed by a 1219 * call to media_pipeline_entity_iter_cleanup after the loop (including in code 1220 * paths that break from the loop). 1221 * 1222 * The same iterator can be used in multiple consecutive loops without being 1223 * destroyed and reinitialized. 1224 * 1225 * Return: 0 on success or a negative error code otherwise. 1226 */ 1227 int media_pipeline_entity_iter_init(struct media_pipeline *pipe, 1228 struct media_pipeline_entity_iter *iter); 1229 1230 /** 1231 * media_pipeline_entity_iter_cleanup - Destroy a pipeline entity iterator 1232 * @iter: The iterator 1233 * 1234 * This function must be called to destroy iterators initialized with 1235 * media_pipeline_entity_iter_init(). 1236 */ 1237 void media_pipeline_entity_iter_cleanup(struct media_pipeline_entity_iter *iter); 1238 1239 struct media_entity * 1240 __media_pipeline_entity_iter_next(struct media_pipeline *pipe, 1241 struct media_pipeline_entity_iter *iter, 1242 struct media_entity *entity); 1243 1244 /** 1245 * media_pipeline_for_each_entity - Iterate on all entities in a media pipeline 1246 * @pipe: The pipeline 1247 * @iter: The iterator (struct media_pipeline_entity_iter) 1248 * @entity: The iterator entity 1249 * 1250 * Iterate on all entities in a media pipeline. This is only valid after the 1251 * pipeline has been built with media_pipeline_start() and before it gets 1252 * destroyed with media_pipeline_stop(). The iterator must be initialized with 1253 * media_pipeline_entity_iter_init() before iteration, and destroyed with 1254 * media_pipeline_entity_iter_cleanup() after (including in code paths that 1255 * break from the loop). 1256 */ 1257 #define media_pipeline_for_each_entity(pipe, iter, entity) \ 1258 for (entity = __media_pipeline_entity_iter_next((pipe), iter, NULL); \ 1259 entity != NULL; \ 1260 entity = __media_pipeline_entity_iter_next((pipe), iter, entity)) 1261 1262 /** 1263 * media_pipeline_alloc_start - Mark a pipeline as streaming 1264 * @pad: Starting pad 1265 * 1266 * media_pipeline_alloc_start() is similar to media_pipeline_start() but instead 1267 * of working on a given pipeline the function will use an existing pipeline if 1268 * the pad is already part of a pipeline, or allocate a new pipeline. 1269 * 1270 * Calls to media_pipeline_alloc_start() must be matched with 1271 * media_pipeline_stop(). 1272 */ 1273 __must_check int media_pipeline_alloc_start(struct media_pad *pad); 1274 1275 /** 1276 * media_devnode_create() - creates and initializes a device node interface 1277 * 1278 * @mdev: pointer to struct &media_device 1279 * @type: type of the interface, as given by 1280 * :ref:`include/uapi/linux/media.h <media_header>` 1281 * ( seek for ``MEDIA_INTF_T_*``) macros. 1282 * @flags: Interface flags, as defined in 1283 * :ref:`include/uapi/linux/media.h <media_header>` 1284 * ( seek for ``MEDIA_INTF_FL_*``) 1285 * @major: Device node major number. 1286 * @minor: Device node minor number. 1287 * 1288 * Return: if succeeded, returns a pointer to the newly allocated 1289 * &media_intf_devnode pointer. 1290 * 1291 * .. note:: 1292 * 1293 * Currently, no flags for &media_interface is defined. 1294 */ 1295 struct media_intf_devnode * 1296 __must_check media_devnode_create(struct media_device *mdev, 1297 u32 type, u32 flags, 1298 u32 major, u32 minor); 1299 /** 1300 * media_devnode_remove() - removes a device node interface 1301 * 1302 * @devnode: pointer to &media_intf_devnode to be freed. 1303 * 1304 * When a device node interface is removed, all links to it are automatically 1305 * removed. 1306 */ 1307 void media_devnode_remove(struct media_intf_devnode *devnode); 1308 1309 /** 1310 * media_create_intf_link() - creates a link between an entity and an interface 1311 * 1312 * @entity: pointer to %media_entity 1313 * @intf: pointer to %media_interface 1314 * @flags: Link flags, as defined in 1315 * :ref:`include/uapi/linux/media.h <media_header>` 1316 * ( seek for ``MEDIA_LNK_FL_*``) 1317 * 1318 * 1319 * Valid values for flags: 1320 * 1321 * %MEDIA_LNK_FL_ENABLED 1322 * Indicates that the interface is connected to the entity hardware. 1323 * That's the default value for interfaces. An interface may be disabled if 1324 * the hardware is busy due to the usage of some other interface that it is 1325 * currently controlling the hardware. 1326 * 1327 * A typical example is an hybrid TV device that handle only one type of 1328 * stream on a given time. So, when the digital TV is streaming, 1329 * the V4L2 interfaces won't be enabled, as such device is not able to 1330 * also stream analog TV or radio. 1331 * 1332 * .. note:: 1333 * 1334 * Before calling this function, media_devnode_create() should be called for 1335 * the interface and media_device_register_entity() should be called for the 1336 * interface that will be part of the link. 1337 */ 1338 struct media_link * 1339 __must_check media_create_intf_link(struct media_entity *entity, 1340 struct media_interface *intf, 1341 u32 flags); 1342 /** 1343 * __media_remove_intf_link() - remove a single interface link 1344 * 1345 * @link: pointer to &media_link. 1346 * 1347 * .. note:: This is an unlocked version of media_remove_intf_link() 1348 */ 1349 void __media_remove_intf_link(struct media_link *link); 1350 1351 /** 1352 * media_remove_intf_link() - remove a single interface link 1353 * 1354 * @link: pointer to &media_link. 1355 * 1356 * .. note:: Prefer to use this one, instead of __media_remove_intf_link() 1357 */ 1358 void media_remove_intf_link(struct media_link *link); 1359 1360 /** 1361 * __media_remove_intf_links() - remove all links associated with an interface 1362 * 1363 * @intf: pointer to &media_interface 1364 * 1365 * .. note:: This is an unlocked version of media_remove_intf_links(). 1366 */ 1367 void __media_remove_intf_links(struct media_interface *intf); 1368 1369 /** 1370 * media_remove_intf_links() - remove all links associated with an interface 1371 * 1372 * @intf: pointer to &media_interface 1373 * 1374 * .. note:: 1375 * 1376 * #) This is called automatically when an entity is unregistered via 1377 * media_device_register_entity() and by media_devnode_remove(). 1378 * 1379 * #) Prefer to use this one, instead of __media_remove_intf_links(). 1380 */ 1381 void media_remove_intf_links(struct media_interface *intf); 1382 1383 /** 1384 * media_entity_call - Calls a struct media_entity_operations operation on 1385 * an entity 1386 * 1387 * @entity: entity where the @operation will be called 1388 * @operation: type of the operation. Should be the name of a member of 1389 * struct &media_entity_operations. 1390 * 1391 * This helper function will check if @operation is not %NULL. On such case, 1392 * it will issue a call to @operation\(@entity, @args\). 1393 */ 1394 1395 #define media_entity_call(entity, operation, args...) \ 1396 (((entity)->ops && (entity)->ops->operation) ? \ 1397 (entity)->ops->operation((entity) , ##args) : -ENOIOCTLCMD) 1398 1399 /** 1400 * media_create_ancillary_link() - create an ancillary link between two 1401 * instances of &media_entity 1402 * 1403 * @primary: pointer to the primary &media_entity 1404 * @ancillary: pointer to the ancillary &media_entity 1405 * 1406 * Create an ancillary link between two entities, indicating that they 1407 * represent two connected pieces of hardware that form a single logical unit. 1408 * A typical example is a camera lens controller being linked to the sensor that 1409 * it is supporting. 1410 * 1411 * The function sets both MEDIA_LNK_FL_ENABLED and MEDIA_LNK_FL_IMMUTABLE for 1412 * the new link. 1413 */ 1414 struct media_link * 1415 media_create_ancillary_link(struct media_entity *primary, 1416 struct media_entity *ancillary); 1417 1418 /** 1419 * __media_entity_next_link() - Iterate through a &media_entity's links 1420 * 1421 * @entity: pointer to the &media_entity 1422 * @link: pointer to a &media_link to hold the iterated values 1423 * @link_type: one of the MEDIA_LNK_FL_LINK_TYPE flags 1424 * 1425 * Return the next link against an entity matching a specific link type. This 1426 * allows iteration through an entity's links whilst guaranteeing all of the 1427 * returned links are of the given type. 1428 */ 1429 struct media_link *__media_entity_next_link(struct media_entity *entity, 1430 struct media_link *link, 1431 unsigned long link_type); 1432 1433 /** 1434 * for_each_media_entity_data_link() - Iterate through an entity's data links 1435 * 1436 * @entity: pointer to the &media_entity 1437 * @link: pointer to a &media_link to hold the iterated values 1438 * 1439 * Iterate over a &media_entity's data links 1440 */ 1441 #define for_each_media_entity_data_link(entity, link) \ 1442 for (link = __media_entity_next_link(entity, NULL, \ 1443 MEDIA_LNK_FL_DATA_LINK); \ 1444 link; \ 1445 link = __media_entity_next_link(entity, link, \ 1446 MEDIA_LNK_FL_DATA_LINK)) 1447 1448 #endif 1449