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 * @sig_type: Type of the signal inside a media pad 229 * @flags: Pad flags, as defined in 230 * :ref:`include/uapi/linux/media.h <media_header>` 231 * (seek for ``MEDIA_PAD_FL_*``) 232 * @pipe: Pipeline this pad belongs to. Use media_entity_pipeline() to 233 * access this field. 234 */ 235 struct media_pad { 236 struct media_gobj graph_obj; /* must be first field in struct */ 237 struct media_entity *entity; 238 u16 index; 239 enum media_pad_signal_type sig_type; 240 unsigned long flags; 241 242 /* 243 * The fields below are private, and should only be accessed via 244 * appropriate functions. 245 */ 246 struct media_pipeline *pipe; 247 }; 248 249 /** 250 * struct media_entity_operations - Media entity operations 251 * @get_fwnode_pad: Return the pad number based on a fwnode endpoint or 252 * a negative value on error. This operation can be used 253 * to map a fwnode to a media pad number. Optional. 254 * @link_setup: Notify the entity of link changes. The operation can 255 * return an error, in which case link setup will be 256 * cancelled. Optional. 257 * @link_validate: Return whether a link is valid from the entity point of 258 * view. The media_pipeline_start() function 259 * validates all links by calling this operation. Optional. 260 * @has_pad_interdep: Return whether two pads of the entity are 261 * interdependent. If two pads are interdependent they are 262 * part of the same pipeline and enabling one of the pads 263 * means that the other pad will become "locked" and 264 * doesn't allow configuration changes. pad0 and pad1 are 265 * guaranteed to not both be sinks or sources. Never call 266 * the .has_pad_interdep() operation directly, always use 267 * media_entity_has_pad_interdep(). 268 * Optional: If the operation isn't implemented all pads 269 * will be considered as interdependent. 270 * 271 * .. note:: 272 * 273 * Those these callbacks are called with struct &media_device.graph_mutex 274 * mutex held. 275 */ 276 struct media_entity_operations { 277 int (*get_fwnode_pad)(struct media_entity *entity, 278 struct fwnode_endpoint *endpoint); 279 int (*link_setup)(struct media_entity *entity, 280 const struct media_pad *local, 281 const struct media_pad *remote, u32 flags); 282 int (*link_validate)(struct media_link *link); 283 bool (*has_pad_interdep)(struct media_entity *entity, unsigned int pad0, 284 unsigned int pad1); 285 }; 286 287 /** 288 * enum media_entity_type - Media entity type 289 * 290 * @MEDIA_ENTITY_TYPE_BASE: 291 * The entity isn't embedded in another subsystem structure. 292 * @MEDIA_ENTITY_TYPE_VIDEO_DEVICE: 293 * The entity is embedded in a struct video_device instance. 294 * @MEDIA_ENTITY_TYPE_V4L2_SUBDEV: 295 * The entity is embedded in a struct v4l2_subdev instance. 296 * 297 * Media entity objects are often not instantiated directly, but the media 298 * entity structure is inherited by (through embedding) other subsystem-specific 299 * structures. The media entity type identifies the type of the subclass 300 * structure that implements a media entity instance. 301 * 302 * This allows runtime type identification of media entities and safe casting to 303 * the correct object type. For instance, a media entity structure instance 304 * embedded in a v4l2_subdev structure instance will have the type 305 * %MEDIA_ENTITY_TYPE_V4L2_SUBDEV and can safely be cast to a &v4l2_subdev 306 * structure using the container_of() macro. 307 */ 308 enum media_entity_type { 309 MEDIA_ENTITY_TYPE_BASE, 310 MEDIA_ENTITY_TYPE_VIDEO_DEVICE, 311 MEDIA_ENTITY_TYPE_V4L2_SUBDEV, 312 }; 313 314 /** 315 * struct media_entity - A media entity graph object. 316 * 317 * @graph_obj: Embedded structure containing the media object common data. 318 * @name: Entity name. 319 * @obj_type: Type of the object that implements the media_entity. 320 * @function: Entity main function, as defined in 321 * :ref:`include/uapi/linux/media.h <media_header>` 322 * (seek for ``MEDIA_ENT_F_*``) 323 * @flags: Entity flags, as defined in 324 * :ref:`include/uapi/linux/media.h <media_header>` 325 * (seek for ``MEDIA_ENT_FL_*``) 326 * @num_pads: Number of sink and source pads. 327 * @num_links: Total number of links, forward and back, enabled and disabled. 328 * @num_backlinks: Number of backlinks 329 * @internal_idx: An unique internal entity specific number. The numbers are 330 * re-used if entities are unregistered or registered again. 331 * @pads: Pads array with the size defined by @num_pads. 332 * @links: List of data links. 333 * @ops: Entity operations. 334 * @use_count: Use count for the entity. 335 * @info: Union with devnode information. Kept just for backward 336 * compatibility. 337 * @info.dev: Contains device major and minor info. 338 * @info.dev.major: device node major, if the device is a devnode. 339 * @info.dev.minor: device node minor, if the device is a devnode. 340 * @major: Devnode major number (zero if not applicable). Kept just 341 * for backward compatibility. 342 * @minor: Devnode minor number (zero if not applicable). Kept just 343 * for backward compatibility. 344 * 345 * .. note:: 346 * 347 * The @use_count reference count must never be negative, but is a signed 348 * integer on purpose: a simple ``WARN_ON(<0)`` check can be used to detect 349 * reference count bugs that would make it negative. 350 */ 351 struct media_entity { 352 struct media_gobj graph_obj; /* must be first field in struct */ 353 const char *name; 354 enum media_entity_type obj_type; 355 u32 function; 356 unsigned long flags; 357 358 u16 num_pads; 359 u16 num_links; 360 u16 num_backlinks; 361 int internal_idx; 362 363 struct media_pad *pads; 364 struct list_head links; 365 366 const struct media_entity_operations *ops; 367 368 int use_count; 369 370 union { 371 struct { 372 u32 major; 373 u32 minor; 374 } dev; 375 } info; 376 }; 377 378 /** 379 * media_entity_for_each_pad - Iterate on all pads in an entity 380 * @entity: The entity the pads belong to 381 * @iter: The iterator pad 382 * 383 * Iterate on all pads in a media entity. 384 */ 385 #define media_entity_for_each_pad(entity, iter) \ 386 for (iter = (entity)->pads; \ 387 iter < &(entity)->pads[(entity)->num_pads]; \ 388 ++iter) 389 390 /** 391 * struct media_interface - A media interface graph object. 392 * 393 * @graph_obj: embedded graph object 394 * @links: List of links pointing to graph entities 395 * @type: Type of the interface as defined in 396 * :ref:`include/uapi/linux/media.h <media_header>` 397 * (seek for ``MEDIA_INTF_T_*``) 398 * @flags: Interface flags as defined in 399 * :ref:`include/uapi/linux/media.h <media_header>` 400 * (seek for ``MEDIA_INTF_FL_*``) 401 * 402 * .. note:: 403 * 404 * Currently, no flags for &media_interface is defined. 405 */ 406 struct media_interface { 407 struct media_gobj graph_obj; 408 struct list_head links; 409 u32 type; 410 u32 flags; 411 }; 412 413 /** 414 * struct media_intf_devnode - A media interface via a device node. 415 * 416 * @intf: embedded interface object 417 * @major: Major number of a device node 418 * @minor: Minor number of a device node 419 */ 420 struct media_intf_devnode { 421 struct media_interface intf; 422 423 /* Should match the fields at media_v2_intf_devnode */ 424 u32 major; 425 u32 minor; 426 }; 427 428 /** 429 * media_entity_id() - return the media entity graph object id 430 * 431 * @entity: pointer to &media_entity 432 */ 433 static inline u32 media_entity_id(struct media_entity *entity) 434 { 435 return entity->graph_obj.id; 436 } 437 438 /** 439 * media_type() - return the media object type 440 * 441 * @gobj: Pointer to the struct &media_gobj graph object 442 */ 443 static inline enum media_gobj_type media_type(struct media_gobj *gobj) 444 { 445 return gobj->id >> MEDIA_BITS_PER_ID; 446 } 447 448 /** 449 * media_id() - return the media object ID 450 * 451 * @gobj: Pointer to the struct &media_gobj graph object 452 */ 453 static inline u32 media_id(struct media_gobj *gobj) 454 { 455 return gobj->id & MEDIA_ID_MASK; 456 } 457 458 /** 459 * media_gobj_gen_id() - encapsulates type and ID on at the object ID 460 * 461 * @type: object type as define at enum &media_gobj_type. 462 * @local_id: next ID, from struct &media_device.id. 463 */ 464 static inline u32 media_gobj_gen_id(enum media_gobj_type type, u64 local_id) 465 { 466 u32 id; 467 468 id = type << MEDIA_BITS_PER_ID; 469 id |= local_id & MEDIA_ID_MASK; 470 471 return id; 472 } 473 474 /** 475 * is_media_entity_v4l2_video_device() - Check if the entity is a video_device 476 * @entity: pointer to entity 477 * 478 * Return: %true if the entity is an instance of a video_device object and can 479 * safely be cast to a struct video_device using the container_of() macro, or 480 * %false otherwise. 481 */ 482 static inline bool is_media_entity_v4l2_video_device(struct media_entity *entity) 483 { 484 return entity && entity->obj_type == MEDIA_ENTITY_TYPE_VIDEO_DEVICE; 485 } 486 487 /** 488 * is_media_entity_v4l2_subdev() - Check if the entity is a v4l2_subdev 489 * @entity: pointer to entity 490 * 491 * Return: %true if the entity is an instance of a &v4l2_subdev object and can 492 * safely be cast to a struct &v4l2_subdev using the container_of() macro, or 493 * %false otherwise. 494 */ 495 static inline bool is_media_entity_v4l2_subdev(struct media_entity *entity) 496 { 497 return entity && entity->obj_type == MEDIA_ENTITY_TYPE_V4L2_SUBDEV; 498 } 499 500 /** 501 * media_entity_enum_init - Initialise an entity enumeration 502 * 503 * @ent_enum: Entity enumeration to be initialised 504 * @mdev: The related media device 505 * 506 * Return: zero on success or a negative error code. 507 */ 508 __must_check int media_entity_enum_init(struct media_entity_enum *ent_enum, 509 struct media_device *mdev); 510 511 /** 512 * media_entity_enum_cleanup - Release resources of an entity enumeration 513 * 514 * @ent_enum: Entity enumeration to be released 515 */ 516 void media_entity_enum_cleanup(struct media_entity_enum *ent_enum); 517 518 /** 519 * media_entity_enum_zero - Clear the entire enum 520 * 521 * @ent_enum: Entity enumeration to be cleared 522 */ 523 static inline void media_entity_enum_zero(struct media_entity_enum *ent_enum) 524 { 525 bitmap_zero(ent_enum->bmap, ent_enum->idx_max); 526 } 527 528 /** 529 * media_entity_enum_set - Mark a single entity in the enum 530 * 531 * @ent_enum: Entity enumeration 532 * @entity: Entity to be marked 533 */ 534 static inline void media_entity_enum_set(struct media_entity_enum *ent_enum, 535 struct media_entity *entity) 536 { 537 if (WARN_ON(entity->internal_idx >= ent_enum->idx_max)) 538 return; 539 540 __set_bit(entity->internal_idx, ent_enum->bmap); 541 } 542 543 /** 544 * media_entity_enum_clear - Unmark a single entity in the enum 545 * 546 * @ent_enum: Entity enumeration 547 * @entity: Entity to be unmarked 548 */ 549 static inline void media_entity_enum_clear(struct media_entity_enum *ent_enum, 550 struct media_entity *entity) 551 { 552 if (WARN_ON(entity->internal_idx >= ent_enum->idx_max)) 553 return; 554 555 __clear_bit(entity->internal_idx, ent_enum->bmap); 556 } 557 558 /** 559 * media_entity_enum_test - Test whether the entity is marked 560 * 561 * @ent_enum: Entity enumeration 562 * @entity: Entity to be tested 563 * 564 * Returns %true if the entity was marked. 565 */ 566 static inline bool media_entity_enum_test(struct media_entity_enum *ent_enum, 567 struct media_entity *entity) 568 { 569 if (WARN_ON(entity->internal_idx >= ent_enum->idx_max)) 570 return true; 571 572 return test_bit(entity->internal_idx, ent_enum->bmap); 573 } 574 575 /** 576 * media_entity_enum_test_and_set - Test whether the entity is marked, 577 * and mark it 578 * 579 * @ent_enum: Entity enumeration 580 * @entity: Entity to be tested 581 * 582 * Returns %true if the entity was marked, and mark it before doing so. 583 */ 584 static inline bool 585 media_entity_enum_test_and_set(struct media_entity_enum *ent_enum, 586 struct media_entity *entity) 587 { 588 if (WARN_ON(entity->internal_idx >= ent_enum->idx_max)) 589 return true; 590 591 return __test_and_set_bit(entity->internal_idx, ent_enum->bmap); 592 } 593 594 /** 595 * media_entity_enum_empty - Test whether the entire enum is empty 596 * 597 * @ent_enum: Entity enumeration 598 * 599 * Return: %true if the entity was empty. 600 */ 601 static inline bool media_entity_enum_empty(struct media_entity_enum *ent_enum) 602 { 603 return bitmap_empty(ent_enum->bmap, ent_enum->idx_max); 604 } 605 606 /** 607 * media_entity_enum_intersects - Test whether two enums intersect 608 * 609 * @ent_enum1: First entity enumeration 610 * @ent_enum2: Second entity enumeration 611 * 612 * Return: %true if entity enumerations @ent_enum1 and @ent_enum2 intersect, 613 * otherwise %false. 614 */ 615 static inline bool media_entity_enum_intersects( 616 struct media_entity_enum *ent_enum1, 617 struct media_entity_enum *ent_enum2) 618 { 619 WARN_ON(ent_enum1->idx_max != ent_enum2->idx_max); 620 621 return bitmap_intersects(ent_enum1->bmap, ent_enum2->bmap, 622 min(ent_enum1->idx_max, ent_enum2->idx_max)); 623 } 624 625 /** 626 * gobj_to_entity - returns the struct &media_entity pointer from the 627 * @gobj contained on it. 628 * 629 * @gobj: Pointer to the struct &media_gobj graph object 630 */ 631 #define gobj_to_entity(gobj) \ 632 container_of(gobj, struct media_entity, graph_obj) 633 634 /** 635 * gobj_to_pad - returns the struct &media_pad pointer from the 636 * @gobj contained on it. 637 * 638 * @gobj: Pointer to the struct &media_gobj graph object 639 */ 640 #define gobj_to_pad(gobj) \ 641 container_of(gobj, struct media_pad, graph_obj) 642 643 /** 644 * gobj_to_link - returns the struct &media_link pointer from the 645 * @gobj contained on it. 646 * 647 * @gobj: Pointer to the struct &media_gobj graph object 648 */ 649 #define gobj_to_link(gobj) \ 650 container_of(gobj, struct media_link, graph_obj) 651 652 /** 653 * gobj_to_intf - returns the struct &media_interface pointer from the 654 * @gobj contained on it. 655 * 656 * @gobj: Pointer to the struct &media_gobj graph object 657 */ 658 #define gobj_to_intf(gobj) \ 659 container_of(gobj, struct media_interface, graph_obj) 660 661 /** 662 * intf_to_devnode - returns the struct media_intf_devnode pointer from the 663 * @intf contained on it. 664 * 665 * @intf: Pointer to struct &media_intf_devnode 666 */ 667 #define intf_to_devnode(intf) \ 668 container_of(intf, struct media_intf_devnode, intf) 669 670 /** 671 * media_gobj_create - Initialize a graph object 672 * 673 * @mdev: Pointer to the &media_device that contains the object 674 * @type: Type of the object 675 * @gobj: Pointer to the struct &media_gobj graph object 676 * 677 * This routine initializes the embedded struct &media_gobj inside a 678 * media graph object. It is called automatically if ``media_*_create`` 679 * function calls are used. However, if the object (entity, link, pad, 680 * interface) is embedded on some other object, this function should be 681 * called before registering the object at the media controller. 682 */ 683 void media_gobj_create(struct media_device *mdev, 684 enum media_gobj_type type, 685 struct media_gobj *gobj); 686 687 /** 688 * media_gobj_destroy - Stop using a graph object on a media device 689 * 690 * @gobj: Pointer to the struct &media_gobj graph object 691 * 692 * This should be called by all routines like media_device_unregister() 693 * that remove/destroy media graph objects. 694 */ 695 void media_gobj_destroy(struct media_gobj *gobj); 696 697 /** 698 * media_entity_pads_init() - Initialize the entity pads 699 * 700 * @entity: entity where the pads belong 701 * @num_pads: total number of sink and source pads 702 * @pads: Array of @num_pads pads. 703 * 704 * The pads array is managed by the entity driver and passed to 705 * media_entity_pads_init() where its pointer will be stored in the 706 * &media_entity structure. 707 * 708 * If no pads are needed, drivers could either directly fill 709 * &media_entity->num_pads with 0 and &media_entity->pads with %NULL or call 710 * this function that will do the same. 711 * 712 * As the number of pads is known in advance, the pads array is not allocated 713 * dynamically but is managed by the entity driver. Most drivers will embed the 714 * pads array in a driver-specific structure, avoiding dynamic allocation. 715 * 716 * Drivers must set the direction of every pad in the pads array before calling 717 * media_entity_pads_init(). The function will initialize the other pads fields. 718 */ 719 int media_entity_pads_init(struct media_entity *entity, u16 num_pads, 720 struct media_pad *pads); 721 722 /** 723 * media_entity_cleanup() - free resources associated with an entity 724 * 725 * @entity: entity where the pads belong 726 * 727 * This function must be called during the cleanup phase after unregistering 728 * the entity (currently, it does nothing). 729 * 730 * Calling media_entity_cleanup() on a media_entity whose memory has been 731 * zeroed but that has not been initialized with media_entity_pad_init() is 732 * valid and is a no-op. 733 */ 734 #if IS_ENABLED(CONFIG_MEDIA_CONTROLLER) 735 static inline void media_entity_cleanup(struct media_entity *entity) {} 736 #else 737 #define media_entity_cleanup(entity) do { } while (false) 738 #endif 739 740 /** 741 * media_get_pad_index() - retrieves a pad index from an entity 742 * 743 * @entity: entity where the pads belong 744 * @pad_type: the type of the pad, one of MEDIA_PAD_FL_* pad types 745 * @sig_type: type of signal of the pad to be search 746 * 747 * This helper function finds the first pad index inside an entity that 748 * satisfies both @is_sink and @sig_type conditions. 749 * 750 * Return: 751 * 752 * On success, return the pad number. If the pad was not found or the media 753 * entity is a NULL pointer, return -EINVAL. 754 */ 755 int media_get_pad_index(struct media_entity *entity, u32 pad_type, 756 enum media_pad_signal_type sig_type); 757 758 /** 759 * media_create_pad_link() - creates a link between two entities. 760 * 761 * @source: pointer to &media_entity of the source pad. 762 * @source_pad: number of the source pad in the pads array 763 * @sink: pointer to &media_entity of the sink pad. 764 * @sink_pad: number of the sink pad in the pads array. 765 * @flags: Link flags, as defined in 766 * :ref:`include/uapi/linux/media.h <media_header>` 767 * ( seek for ``MEDIA_LNK_FL_*``) 768 * 769 * Valid values for flags: 770 * 771 * %MEDIA_LNK_FL_ENABLED 772 * Indicates that the link is enabled and can be used to transfer media data. 773 * When two or more links target a sink pad, only one of them can be 774 * enabled at a time. 775 * 776 * %MEDIA_LNK_FL_IMMUTABLE 777 * Indicates that the link enabled state can't be modified at runtime. If 778 * %MEDIA_LNK_FL_IMMUTABLE is set, then %MEDIA_LNK_FL_ENABLED must also be 779 * set, since an immutable link is always enabled. 780 * 781 * .. note:: 782 * 783 * Before calling this function, media_entity_pads_init() and 784 * media_device_register_entity() should be called previously for both ends. 785 */ 786 __must_check int media_create_pad_link(struct media_entity *source, 787 u16 source_pad, struct media_entity *sink, 788 u16 sink_pad, u32 flags); 789 790 /** 791 * media_create_pad_links() - creates a link between two entities. 792 * 793 * @mdev: Pointer to the media_device that contains the object 794 * @source_function: Function of the source entities. Used only if @source is 795 * NULL. 796 * @source: pointer to &media_entity of the source pad. If NULL, it will use 797 * all entities that matches the @sink_function. 798 * @source_pad: number of the source pad in the pads array 799 * @sink_function: Function of the sink entities. Used only if @sink is NULL. 800 * @sink: pointer to &media_entity of the sink pad. If NULL, it will use 801 * all entities that matches the @sink_function. 802 * @sink_pad: number of the sink pad in the pads array. 803 * @flags: Link flags, as defined in include/uapi/linux/media.h. 804 * @allow_both_undefined: if %true, then both @source and @sink can be NULL. 805 * In such case, it will create a crossbar between all entities that 806 * matches @source_function to all entities that matches @sink_function. 807 * If %false, it will return 0 and won't create any link if both @source 808 * and @sink are NULL. 809 * 810 * Valid values for flags: 811 * 812 * A %MEDIA_LNK_FL_ENABLED flag indicates that the link is enabled and can be 813 * used to transfer media data. If multiple links are created and this 814 * flag is passed as an argument, only the first created link will have 815 * this flag. 816 * 817 * A %MEDIA_LNK_FL_IMMUTABLE flag indicates that the link enabled state can't 818 * be modified at runtime. If %MEDIA_LNK_FL_IMMUTABLE is set, then 819 * %MEDIA_LNK_FL_ENABLED must also be set since an immutable link is 820 * always enabled. 821 * 822 * It is common for some devices to have multiple source and/or sink entities 823 * of the same type that should be linked. While media_create_pad_link() 824 * creates link by link, this function is meant to allow 1:n, n:1 and even 825 * cross-bar (n:n) links. 826 * 827 * .. note:: 828 * 829 * Before calling this function, media_entity_pads_init() and 830 * media_device_register_entity() should be called previously for the 831 * entities to be linked. 832 */ 833 int media_create_pad_links(const struct media_device *mdev, 834 const u32 source_function, 835 struct media_entity *source, 836 const u16 source_pad, 837 const u32 sink_function, 838 struct media_entity *sink, 839 const u16 sink_pad, 840 u32 flags, 841 const bool allow_both_undefined); 842 843 void __media_entity_remove_links(struct media_entity *entity); 844 845 /** 846 * media_entity_remove_links() - remove all links associated with an entity 847 * 848 * @entity: pointer to &media_entity 849 * 850 * .. note:: 851 * 852 * This is called automatically when an entity is unregistered via 853 * media_device_register_entity(). 854 */ 855 void media_entity_remove_links(struct media_entity *entity); 856 857 /** 858 * __media_entity_setup_link - Configure a media link without locking 859 * @link: The link being configured 860 * @flags: Link configuration flags 861 * 862 * The bulk of link setup is handled by the two entities connected through the 863 * link. This function notifies both entities of the link configuration change. 864 * 865 * If the link is immutable or if the current and new configuration are 866 * identical, return immediately. 867 * 868 * The user is expected to hold link->source->parent->mutex. If not, 869 * media_entity_setup_link() should be used instead. 870 */ 871 int __media_entity_setup_link(struct media_link *link, u32 flags); 872 873 /** 874 * media_entity_setup_link() - changes the link flags properties in runtime 875 * 876 * @link: pointer to &media_link 877 * @flags: the requested new link flags 878 * 879 * The only configurable property is the %MEDIA_LNK_FL_ENABLED link flag 880 * to enable/disable a link. Links marked with the 881 * %MEDIA_LNK_FL_IMMUTABLE link flag can not be enabled or disabled. 882 * 883 * When a link is enabled or disabled, the media framework calls the 884 * link_setup operation for the two entities at the source and sink of the 885 * link, in that order. If the second link_setup call fails, another 886 * link_setup call is made on the first entity to restore the original link 887 * flags. 888 * 889 * Media device drivers can be notified of link setup operations by setting the 890 * &media_device.link_notify pointer to a callback function. If provided, the 891 * notification callback will be called before enabling and after disabling 892 * links. 893 * 894 * Entity drivers must implement the link_setup operation if any of their links 895 * is non-immutable. The operation must either configure the hardware or store 896 * the configuration information to be applied later. 897 * 898 * Link configuration must not have any side effect on other links. If an 899 * enabled link at a sink pad prevents another link at the same pad from 900 * being enabled, the link_setup operation must return %-EBUSY and can't 901 * implicitly disable the first enabled link. 902 * 903 * .. note:: 904 * 905 * The valid values of the flags for the link is the same as described 906 * on media_create_pad_link(), for pad to pad links or the same as described 907 * on media_create_intf_link(), for interface to entity links. 908 */ 909 int media_entity_setup_link(struct media_link *link, u32 flags); 910 911 /** 912 * media_entity_find_link - Find a link between two pads 913 * @source: Source pad 914 * @sink: Sink pad 915 * 916 * Return: returns a pointer to the link between the two entities. If no 917 * such link exists, return %NULL. 918 */ 919 struct media_link *media_entity_find_link(struct media_pad *source, 920 struct media_pad *sink); 921 922 /** 923 * media_pad_remote_pad_first - Find the first pad at the remote end of a link 924 * @pad: Pad at the local end of the link 925 * 926 * Search for a remote pad connected to the given pad by iterating over all 927 * links originating or terminating at that pad until an enabled link is found. 928 * 929 * Return: returns a pointer to the pad at the remote end of the first found 930 * enabled link, or %NULL if no enabled link has been found. 931 */ 932 struct media_pad *media_pad_remote_pad_first(const struct media_pad *pad); 933 934 /** 935 * media_pad_remote_pad_unique - Find a remote pad connected to a pad 936 * @pad: The pad 937 * 938 * Search for and return a remote pad connected to @pad through an enabled 939 * link. If multiple (or no) remote pads are found, an error is returned. 940 * 941 * The uniqueness constraint makes this helper function suitable for entities 942 * that support a single active source at a time on a given pad. 943 * 944 * Return: A pointer to the remote pad, or one of the following error pointers 945 * if an error occurs: 946 * 947 * * -ENOTUNIQ - Multiple links are enabled 948 * * -ENOLINK - No connected pad found 949 */ 950 struct media_pad *media_pad_remote_pad_unique(const struct media_pad *pad); 951 952 /** 953 * media_entity_remote_pad_unique - Find a remote pad connected to an entity 954 * @entity: The entity 955 * @type: The type of pad to find (MEDIA_PAD_FL_SINK or MEDIA_PAD_FL_SOURCE) 956 * 957 * Search for and return a remote pad of @type connected to @entity through an 958 * enabled link. If multiple (or no) remote pads match these criteria, an error 959 * is returned. 960 * 961 * The uniqueness constraint makes this helper function suitable for entities 962 * that support a single active source or sink at a time. 963 * 964 * Return: A pointer to the remote pad, or one of the following error pointers 965 * if an error occurs: 966 * 967 * * -ENOTUNIQ - Multiple links are enabled 968 * * -ENOLINK - No connected pad found 969 */ 970 struct media_pad * 971 media_entity_remote_pad_unique(const struct media_entity *entity, 972 unsigned int type); 973 974 /** 975 * media_entity_remote_source_pad_unique - Find a remote source pad connected to 976 * an entity 977 * @entity: The entity 978 * 979 * Search for and return a remote source pad connected to @entity through an 980 * enabled link. If multiple (or no) remote pads match these criteria, an error 981 * is returned. 982 * 983 * The uniqueness constraint makes this helper function suitable for entities 984 * that support a single active source at a time. 985 * 986 * Return: A pointer to the remote pad, or one of the following error pointers 987 * if an error occurs: 988 * 989 * * -ENOTUNIQ - Multiple links are enabled 990 * * -ENOLINK - No connected pad found 991 */ 992 static inline struct media_pad * 993 media_entity_remote_source_pad_unique(const struct media_entity *entity) 994 { 995 return media_entity_remote_pad_unique(entity, MEDIA_PAD_FL_SOURCE); 996 } 997 998 /** 999 * media_pad_is_streaming - Test if a pad is part of a streaming pipeline 1000 * @pad: The pad 1001 * 1002 * Return: True if the pad is part of a pipeline started with the 1003 * media_pipeline_start() function, false otherwise. 1004 */ 1005 static inline bool media_pad_is_streaming(const struct media_pad *pad) 1006 { 1007 return pad->pipe; 1008 } 1009 1010 /** 1011 * media_entity_is_streaming - Test if an entity is part of a streaming pipeline 1012 * @entity: The entity 1013 * 1014 * Return: True if the entity is part of a pipeline started with the 1015 * media_pipeline_start() function, false otherwise. 1016 */ 1017 static inline bool media_entity_is_streaming(const struct media_entity *entity) 1018 { 1019 struct media_pad *pad; 1020 1021 media_entity_for_each_pad(entity, pad) { 1022 if (media_pad_is_streaming(pad)) 1023 return true; 1024 } 1025 1026 return false; 1027 } 1028 1029 /** 1030 * media_entity_pipeline - Get the media pipeline an entity is part of 1031 * @entity: The entity 1032 * 1033 * DEPRECATED: use media_pad_pipeline() instead. 1034 * 1035 * This function returns the media pipeline that an entity has been associated 1036 * with when constructing the pipeline with media_pipeline_start(). The pointer 1037 * remains valid until media_pipeline_stop() is called. 1038 * 1039 * In general, entities can be part of multiple pipelines, when carrying 1040 * multiple streams (either on different pads, or on the same pad using 1041 * multiplexed streams). This function is to be used only for entities that 1042 * do not support multiple pipelines. 1043 * 1044 * Return: The media_pipeline the entity is part of, or NULL if the entity is 1045 * not part of any pipeline. 1046 */ 1047 struct media_pipeline *media_entity_pipeline(struct media_entity *entity); 1048 1049 /** 1050 * media_pad_pipeline - Get the media pipeline a pad is part of 1051 * @pad: The pad 1052 * 1053 * This function returns the media pipeline that a pad has been associated 1054 * with when constructing the pipeline with media_pipeline_start(). The pointer 1055 * remains valid until media_pipeline_stop() is called. 1056 * 1057 * Return: The media_pipeline the pad is part of, or NULL if the pad is 1058 * not part of any pipeline. 1059 */ 1060 struct media_pipeline *media_pad_pipeline(struct media_pad *pad); 1061 1062 /** 1063 * media_entity_get_fwnode_pad - Get pad number from fwnode 1064 * 1065 * @entity: The entity 1066 * @fwnode: Pointer to the fwnode_handle which should be used to find the pad 1067 * @direction_flags: Expected direction of the pad, as defined in 1068 * :ref:`include/uapi/linux/media.h <media_header>` 1069 * (seek for ``MEDIA_PAD_FL_*``) 1070 * 1071 * This function can be used to resolve the media pad number from 1072 * a fwnode. This is useful for devices which use more complex 1073 * mappings of media pads. 1074 * 1075 * If the entity does not implement the get_fwnode_pad() operation 1076 * then this function searches the entity for the first pad that 1077 * matches the @direction_flags. 1078 * 1079 * Return: returns the pad number on success or a negative error code. 1080 */ 1081 int media_entity_get_fwnode_pad(struct media_entity *entity, 1082 const struct fwnode_handle *fwnode, 1083 unsigned long direction_flags); 1084 1085 /** 1086 * media_graph_walk_init - Allocate resources used by graph walk. 1087 * 1088 * @graph: Media graph structure that will be used to walk the graph 1089 * @mdev: Pointer to the &media_device that contains the object 1090 * 1091 * This function is deprecated, use media_pipeline_for_each_pad() instead. 1092 * 1093 * The caller is required to hold the media_device graph_mutex during the graph 1094 * walk until the graph state is released. 1095 * 1096 * Returns zero on success or a negative error code otherwise. 1097 */ 1098 __must_check int media_graph_walk_init( 1099 struct media_graph *graph, struct media_device *mdev); 1100 1101 /** 1102 * media_graph_walk_cleanup - Release resources used by graph walk. 1103 * 1104 * @graph: Media graph structure that will be used to walk the graph 1105 * 1106 * This function is deprecated, use media_pipeline_for_each_pad() instead. 1107 */ 1108 void media_graph_walk_cleanup(struct media_graph *graph); 1109 1110 /** 1111 * media_graph_walk_start - Start walking the media graph at a 1112 * given entity 1113 * 1114 * @graph: Media graph structure that will be used to walk the graph 1115 * @entity: Starting entity 1116 * 1117 * This function is deprecated, use media_pipeline_for_each_pad() instead. 1118 * 1119 * Before using this function, media_graph_walk_init() must be 1120 * used to allocate resources used for walking the graph. This 1121 * function initializes the graph traversal structure to walk the 1122 * entities graph starting at the given entity. The traversal 1123 * structure must not be modified by the caller during graph 1124 * traversal. After the graph walk, the resources must be released 1125 * using media_graph_walk_cleanup(). 1126 */ 1127 void media_graph_walk_start(struct media_graph *graph, 1128 struct media_entity *entity); 1129 1130 /** 1131 * media_graph_walk_next - Get the next entity in the graph 1132 * @graph: Media graph structure 1133 * 1134 * This function is deprecated, use media_pipeline_for_each_pad() instead. 1135 * 1136 * Perform a depth-first traversal of the given media entities graph. 1137 * 1138 * The graph structure must have been previously initialized with a call to 1139 * media_graph_walk_start(). 1140 * 1141 * Return: returns the next entity in the graph or %NULL if the whole graph 1142 * have been traversed. 1143 */ 1144 struct media_entity *media_graph_walk_next(struct media_graph *graph); 1145 1146 /** 1147 * media_pipeline_start - Mark a pipeline as streaming 1148 * @pad: Starting pad 1149 * @pipe: Media pipeline to be assigned to all pads in the pipeline. 1150 * 1151 * Mark all pads connected to a given pad through enabled links, either 1152 * directly or indirectly, as streaming. The given pipeline object is assigned 1153 * to every pad in the pipeline and stored in the media_pad pipe field. 1154 * 1155 * Calls to this function can be nested, in which case the same number of 1156 * media_pipeline_stop() calls will be required to stop streaming. The 1157 * pipeline pointer must be identical for all nested calls to 1158 * media_pipeline_start(). 1159 */ 1160 __must_check int media_pipeline_start(struct media_pad *pad, 1161 struct media_pipeline *pipe); 1162 /** 1163 * __media_pipeline_start - Mark a pipeline as streaming 1164 * 1165 * @pad: Starting pad 1166 * @pipe: Media pipeline to be assigned to all pads in the pipeline. 1167 * 1168 * ..note:: This is the non-locking version of media_pipeline_start() 1169 */ 1170 __must_check int __media_pipeline_start(struct media_pad *pad, 1171 struct media_pipeline *pipe); 1172 1173 /** 1174 * media_pipeline_stop - Mark a pipeline as not streaming 1175 * @pad: Starting pad 1176 * 1177 * Mark all pads connected to a given pad through enabled links, either 1178 * directly or indirectly, as not streaming. The media_pad pipe field is 1179 * reset to %NULL. 1180 * 1181 * If multiple calls to media_pipeline_start() have been made, the same 1182 * number of calls to this function are required to mark the pipeline as not 1183 * streaming. 1184 */ 1185 void media_pipeline_stop(struct media_pad *pad); 1186 1187 /** 1188 * __media_pipeline_stop - Mark a pipeline as not streaming 1189 * 1190 * @pad: Starting pad 1191 * 1192 * .. note:: This is the non-locking version of media_pipeline_stop() 1193 */ 1194 void __media_pipeline_stop(struct media_pad *pad); 1195 1196 struct media_pad * 1197 __media_pipeline_pad_iter_next(struct media_pipeline *pipe, 1198 struct media_pipeline_pad_iter *iter, 1199 struct media_pad *pad); 1200 1201 /** 1202 * media_pipeline_for_each_pad - Iterate on all pads in a media pipeline 1203 * @pipe: The pipeline 1204 * @iter: The iterator (struct media_pipeline_pad_iter) 1205 * @pad: The iterator pad 1206 * 1207 * Iterate on all pads in a media pipeline. This is only valid after the 1208 * pipeline has been built with media_pipeline_start() and before it gets 1209 * destroyed with media_pipeline_stop(). 1210 */ 1211 #define media_pipeline_for_each_pad(pipe, iter, pad) \ 1212 for (pad = __media_pipeline_pad_iter_next((pipe), iter, NULL); \ 1213 pad != NULL; \ 1214 pad = __media_pipeline_pad_iter_next((pipe), iter, pad)) 1215 1216 /** 1217 * media_pipeline_entity_iter_init - Initialize a pipeline entity iterator 1218 * @pipe: The pipeline 1219 * @iter: The iterator 1220 * 1221 * This function must be called to initialize the iterator before using it in a 1222 * media_pipeline_for_each_entity() loop. The iterator must be destroyed by a 1223 * call to media_pipeline_entity_iter_cleanup after the loop (including in code 1224 * paths that break from the loop). 1225 * 1226 * The same iterator can be used in multiple consecutive loops without being 1227 * destroyed and reinitialized. 1228 * 1229 * Return: 0 on success or a negative error code otherwise. 1230 */ 1231 int media_pipeline_entity_iter_init(struct media_pipeline *pipe, 1232 struct media_pipeline_entity_iter *iter); 1233 1234 /** 1235 * media_pipeline_entity_iter_cleanup - Destroy a pipeline entity iterator 1236 * @iter: The iterator 1237 * 1238 * This function must be called to destroy iterators initialized with 1239 * media_pipeline_entity_iter_init(). 1240 */ 1241 void media_pipeline_entity_iter_cleanup(struct media_pipeline_entity_iter *iter); 1242 1243 struct media_entity * 1244 __media_pipeline_entity_iter_next(struct media_pipeline *pipe, 1245 struct media_pipeline_entity_iter *iter, 1246 struct media_entity *entity); 1247 1248 /** 1249 * media_pipeline_for_each_entity - Iterate on all entities in a media pipeline 1250 * @pipe: The pipeline 1251 * @iter: The iterator (struct media_pipeline_entity_iter) 1252 * @entity: The iterator entity 1253 * 1254 * Iterate on all entities in a media pipeline. This is only valid after the 1255 * pipeline has been built with media_pipeline_start() and before it gets 1256 * destroyed with media_pipeline_stop(). The iterator must be initialized with 1257 * media_pipeline_entity_iter_init() before iteration, and destroyed with 1258 * media_pipeline_entity_iter_cleanup() after (including in code paths that 1259 * break from the loop). 1260 */ 1261 #define media_pipeline_for_each_entity(pipe, iter, entity) \ 1262 for (entity = __media_pipeline_entity_iter_next((pipe), iter, NULL); \ 1263 entity != NULL; \ 1264 entity = __media_pipeline_entity_iter_next((pipe), iter, entity)) 1265 1266 /** 1267 * media_pipeline_alloc_start - Mark a pipeline as streaming 1268 * @pad: Starting pad 1269 * 1270 * media_pipeline_alloc_start() is similar to media_pipeline_start() but instead 1271 * of working on a given pipeline the function will use an existing pipeline if 1272 * the pad is already part of a pipeline, or allocate a new pipeline. 1273 * 1274 * Calls to media_pipeline_alloc_start() must be matched with 1275 * media_pipeline_stop(). 1276 */ 1277 __must_check int media_pipeline_alloc_start(struct media_pad *pad); 1278 1279 /** 1280 * media_devnode_create() - creates and initializes a device node interface 1281 * 1282 * @mdev: pointer to struct &media_device 1283 * @type: type of the interface, as given by 1284 * :ref:`include/uapi/linux/media.h <media_header>` 1285 * ( seek for ``MEDIA_INTF_T_*``) macros. 1286 * @flags: Interface flags, as defined in 1287 * :ref:`include/uapi/linux/media.h <media_header>` 1288 * ( seek for ``MEDIA_INTF_FL_*``) 1289 * @major: Device node major number. 1290 * @minor: Device node minor number. 1291 * 1292 * Return: if succeeded, returns a pointer to the newly allocated 1293 * &media_intf_devnode pointer. 1294 * 1295 * .. note:: 1296 * 1297 * Currently, no flags for &media_interface is defined. 1298 */ 1299 struct media_intf_devnode * 1300 __must_check media_devnode_create(struct media_device *mdev, 1301 u32 type, u32 flags, 1302 u32 major, u32 minor); 1303 /** 1304 * media_devnode_remove() - removes a device node interface 1305 * 1306 * @devnode: pointer to &media_intf_devnode to be freed. 1307 * 1308 * When a device node interface is removed, all links to it are automatically 1309 * removed. 1310 */ 1311 void media_devnode_remove(struct media_intf_devnode *devnode); 1312 1313 /** 1314 * media_create_intf_link() - creates a link between an entity and an interface 1315 * 1316 * @entity: pointer to %media_entity 1317 * @intf: pointer to %media_interface 1318 * @flags: Link flags, as defined in 1319 * :ref:`include/uapi/linux/media.h <media_header>` 1320 * ( seek for ``MEDIA_LNK_FL_*``) 1321 * 1322 * 1323 * Valid values for flags: 1324 * 1325 * %MEDIA_LNK_FL_ENABLED 1326 * Indicates that the interface is connected to the entity hardware. 1327 * That's the default value for interfaces. An interface may be disabled if 1328 * the hardware is busy due to the usage of some other interface that it is 1329 * currently controlling the hardware. 1330 * 1331 * A typical example is an hybrid TV device that handle only one type of 1332 * stream on a given time. So, when the digital TV is streaming, 1333 * the V4L2 interfaces won't be enabled, as such device is not able to 1334 * also stream analog TV or radio. 1335 * 1336 * .. note:: 1337 * 1338 * Before calling this function, media_devnode_create() should be called for 1339 * the interface and media_device_register_entity() should be called for the 1340 * interface that will be part of the link. 1341 */ 1342 struct media_link * 1343 __must_check media_create_intf_link(struct media_entity *entity, 1344 struct media_interface *intf, 1345 u32 flags); 1346 /** 1347 * __media_remove_intf_link() - remove a single interface link 1348 * 1349 * @link: pointer to &media_link. 1350 * 1351 * .. note:: This is an unlocked version of media_remove_intf_link() 1352 */ 1353 void __media_remove_intf_link(struct media_link *link); 1354 1355 /** 1356 * media_remove_intf_link() - remove a single interface link 1357 * 1358 * @link: pointer to &media_link. 1359 * 1360 * .. note:: Prefer to use this one, instead of __media_remove_intf_link() 1361 */ 1362 void media_remove_intf_link(struct media_link *link); 1363 1364 /** 1365 * __media_remove_intf_links() - remove all links associated with an interface 1366 * 1367 * @intf: pointer to &media_interface 1368 * 1369 * .. note:: This is an unlocked version of media_remove_intf_links(). 1370 */ 1371 void __media_remove_intf_links(struct media_interface *intf); 1372 1373 /** 1374 * media_remove_intf_links() - remove all links associated with an interface 1375 * 1376 * @intf: pointer to &media_interface 1377 * 1378 * .. note:: 1379 * 1380 * #) This is called automatically when an entity is unregistered via 1381 * media_device_register_entity() and by media_devnode_remove(). 1382 * 1383 * #) Prefer to use this one, instead of __media_remove_intf_links(). 1384 */ 1385 void media_remove_intf_links(struct media_interface *intf); 1386 1387 /** 1388 * media_entity_call - Calls a struct media_entity_operations operation on 1389 * an entity 1390 * 1391 * @entity: entity where the @operation will be called 1392 * @operation: type of the operation. Should be the name of a member of 1393 * struct &media_entity_operations. 1394 * 1395 * This helper function will check if @operation is not %NULL. On such case, 1396 * it will issue a call to @operation\(@entity, @args\). 1397 */ 1398 1399 #define media_entity_call(entity, operation, args...) \ 1400 (((entity)->ops && (entity)->ops->operation) ? \ 1401 (entity)->ops->operation((entity) , ##args) : -ENOIOCTLCMD) 1402 1403 /** 1404 * media_create_ancillary_link() - create an ancillary link between two 1405 * instances of &media_entity 1406 * 1407 * @primary: pointer to the primary &media_entity 1408 * @ancillary: pointer to the ancillary &media_entity 1409 * 1410 * Create an ancillary link between two entities, indicating that they 1411 * represent two connected pieces of hardware that form a single logical unit. 1412 * A typical example is a camera lens controller being linked to the sensor that 1413 * it is supporting. 1414 * 1415 * The function sets both MEDIA_LNK_FL_ENABLED and MEDIA_LNK_FL_IMMUTABLE for 1416 * the new link. 1417 */ 1418 struct media_link * 1419 media_create_ancillary_link(struct media_entity *primary, 1420 struct media_entity *ancillary); 1421 1422 /** 1423 * __media_entity_next_link() - Iterate through a &media_entity's links 1424 * 1425 * @entity: pointer to the &media_entity 1426 * @link: pointer to a &media_link to hold the iterated values 1427 * @link_type: one of the MEDIA_LNK_FL_LINK_TYPE flags 1428 * 1429 * Return the next link against an entity matching a specific link type. This 1430 * allows iteration through an entity's links whilst guaranteeing all of the 1431 * returned links are of the given type. 1432 */ 1433 struct media_link *__media_entity_next_link(struct media_entity *entity, 1434 struct media_link *link, 1435 unsigned long link_type); 1436 1437 /** 1438 * for_each_media_entity_data_link() - Iterate through an entity's data links 1439 * 1440 * @entity: pointer to the &media_entity 1441 * @link: pointer to a &media_link to hold the iterated values 1442 * 1443 * Iterate over a &media_entity's data links 1444 */ 1445 #define for_each_media_entity_data_link(entity, link) \ 1446 for (link = __media_entity_next_link(entity, NULL, \ 1447 MEDIA_LNK_FL_DATA_LINK); \ 1448 link; \ 1449 link = __media_entity_next_link(entity, link, \ 1450 MEDIA_LNK_FL_DATA_LINK)) 1451 1452 #endif 1453