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