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/fwnode.h> 17 #include <linux/kernel.h> 18 #include <linux/list.h> 19 #include <linux/media.h> 20 21 /* Enums used internally at the media controller to represent graphs */ 22 23 /** 24 * enum media_gobj_type - type of a graph object 25 * 26 * @MEDIA_GRAPH_ENTITY: Identify a media entity 27 * @MEDIA_GRAPH_PAD: Identify a media pad 28 * @MEDIA_GRAPH_LINK: Identify a media link 29 * @MEDIA_GRAPH_INTF_DEVNODE: Identify a media Kernel API interface via 30 * a device node 31 */ 32 enum media_gobj_type { 33 MEDIA_GRAPH_ENTITY, 34 MEDIA_GRAPH_PAD, 35 MEDIA_GRAPH_LINK, 36 MEDIA_GRAPH_INTF_DEVNODE, 37 }; 38 39 #define MEDIA_BITS_PER_TYPE 8 40 #define MEDIA_BITS_PER_ID (32 - MEDIA_BITS_PER_TYPE) 41 #define MEDIA_ID_MASK GENMASK_ULL(MEDIA_BITS_PER_ID - 1, 0) 42 43 /* Structs to represent the objects that belong to a media graph */ 44 45 /** 46 * struct media_gobj - Define a graph object. 47 * 48 * @mdev: Pointer to the struct &media_device that owns the object 49 * @id: Non-zero object ID identifier. The ID should be unique 50 * inside a media_device, as it is composed by 51 * %MEDIA_BITS_PER_TYPE to store the type plus 52 * %MEDIA_BITS_PER_ID to store the ID 53 * @list: List entry stored in one of the per-type mdev object lists 54 * 55 * All objects on the media graph should have this struct embedded 56 */ 57 struct media_gobj { 58 struct media_device *mdev; 59 u32 id; 60 struct list_head list; 61 }; 62 63 #define MEDIA_ENTITY_ENUM_MAX_DEPTH 16 64 65 /** 66 * struct media_entity_enum - An enumeration of media entities. 67 * 68 * @bmap: Bit map in which each bit represents one entity at struct 69 * media_entity->internal_idx. 70 * @idx_max: Number of bits in bmap 71 */ 72 struct media_entity_enum { 73 unsigned long *bmap; 74 int idx_max; 75 }; 76 77 /** 78 * struct media_graph - Media graph traversal state 79 * 80 * @stack: Graph traversal stack; the stack contains information 81 * on the path the media entities to be walked and the 82 * links through which they were reached. 83 * @stack.entity: pointer to &struct media_entity at the graph. 84 * @stack.link: pointer to &struct list_head. 85 * @ent_enum: Visited entities 86 * @top: The top of the stack 87 */ 88 struct media_graph { 89 struct { 90 struct media_entity *entity; 91 struct list_head *link; 92 } stack[MEDIA_ENTITY_ENUM_MAX_DEPTH]; 93 94 struct media_entity_enum ent_enum; 95 int top; 96 }; 97 98 /** 99 * struct media_pipeline - Media pipeline related information 100 * 101 * @streaming_count: Streaming start count - streaming stop count 102 * @graph: Media graph walk during pipeline start / stop 103 */ 104 struct media_pipeline { 105 int streaming_count; 106 struct media_graph graph; 107 }; 108 109 /** 110 * struct media_link - A link object part of a media graph. 111 * 112 * @graph_obj: Embedded structure containing the media object common data 113 * @list: Linked list associated with an entity or an interface that 114 * owns the link. 115 * @gobj0: Part of a union. Used to get the pointer for the first 116 * graph_object of the link. 117 * @source: Part of a union. Used only if the first object (gobj0) is 118 * a pad. In that case, it represents the source pad. 119 * @intf: Part of a union. Used only if the first object (gobj0) is 120 * an interface. 121 * @gobj1: Part of a union. Used to get the pointer for the second 122 * graph_object of the link. 123 * @sink: Part of a union. Used only if the second object (gobj1) is 124 * a pad. In that case, it represents the sink pad. 125 * @entity: Part of a union. Used only if the second object (gobj1) is 126 * an entity. 127 * @reverse: Pointer to the link for the reverse direction of a pad to pad 128 * link. 129 * @flags: Link flags, as defined in uapi/media.h (MEDIA_LNK_FL_*) 130 * @is_backlink: Indicate if the link is a backlink. 131 */ 132 struct media_link { 133 struct media_gobj graph_obj; 134 struct list_head list; 135 union { 136 struct media_gobj *gobj0; 137 struct media_pad *source; 138 struct media_interface *intf; 139 }; 140 union { 141 struct media_gobj *gobj1; 142 struct media_pad *sink; 143 struct media_entity *entity; 144 }; 145 struct media_link *reverse; 146 unsigned long flags; 147 bool is_backlink; 148 }; 149 150 /** 151 * enum media_pad_signal_type - type of the signal inside a media pad 152 * 153 * @PAD_SIGNAL_DEFAULT: 154 * Default signal. Use this when all inputs or all outputs are 155 * uniquely identified by the pad number. 156 * @PAD_SIGNAL_ANALOG: 157 * The pad contains an analog signal. It can be Radio Frequency, 158 * Intermediate Frequency, a baseband signal or sub-cariers. 159 * Tuner inputs, IF-PLL demodulators, composite and s-video signals 160 * should use it. 161 * @PAD_SIGNAL_DV: 162 * Contains a digital video signal, with can be a bitstream of samples 163 * taken from an analog TV video source. On such case, it usually 164 * contains the VBI data on it. 165 * @PAD_SIGNAL_AUDIO: 166 * Contains an Intermediate Frequency analog signal from an audio 167 * sub-carrier or an audio bitstream. IF signals are provided by tuners 168 * and consumed by audio AM/FM decoders. Bitstream audio is provided by 169 * an audio decoder. 170 */ 171 enum media_pad_signal_type { 172 PAD_SIGNAL_DEFAULT = 0, 173 PAD_SIGNAL_ANALOG, 174 PAD_SIGNAL_DV, 175 PAD_SIGNAL_AUDIO, 176 }; 177 178 /** 179 * struct media_pad - A media pad graph object. 180 * 181 * @graph_obj: Embedded structure containing the media object common data 182 * @entity: Entity this pad belongs to 183 * @index: Pad index in the entity pads array, numbered from 0 to n 184 * @sig_type: Type of the signal inside a media pad 185 * @flags: Pad flags, as defined in 186 * :ref:`include/uapi/linux/media.h <media_header>` 187 * (seek for ``MEDIA_PAD_FL_*``) 188 */ 189 struct media_pad { 190 struct media_gobj graph_obj; /* must be first field in struct */ 191 struct media_entity *entity; 192 u16 index; 193 enum media_pad_signal_type sig_type; 194 unsigned long flags; 195 }; 196 197 /** 198 * struct media_entity_operations - Media entity operations 199 * @get_fwnode_pad: Return the pad number based on a fwnode endpoint or 200 * a negative value on error. This operation can be used 201 * to map a fwnode to a media pad number. Optional. 202 * @link_setup: Notify the entity of link changes. The operation can 203 * return an error, in which case link setup will be 204 * cancelled. Optional. 205 * @link_validate: Return whether a link is valid from the entity point of 206 * view. The media_pipeline_start() function 207 * validates all links by calling this operation. Optional. 208 * 209 * .. note:: 210 * 211 * Those these callbacks are called with struct &media_device.graph_mutex 212 * mutex held. 213 */ 214 struct media_entity_operations { 215 int (*get_fwnode_pad)(struct fwnode_endpoint *endpoint); 216 int (*link_setup)(struct media_entity *entity, 217 const struct media_pad *local, 218 const struct media_pad *remote, u32 flags); 219 int (*link_validate)(struct media_link *link); 220 }; 221 222 /** 223 * enum media_entity_type - Media entity type 224 * 225 * @MEDIA_ENTITY_TYPE_BASE: 226 * The entity isn't embedded in another subsystem structure. 227 * @MEDIA_ENTITY_TYPE_VIDEO_DEVICE: 228 * The entity is embedded in a struct video_device instance. 229 * @MEDIA_ENTITY_TYPE_V4L2_SUBDEV: 230 * The entity is embedded in a struct v4l2_subdev instance. 231 * 232 * Media entity objects are often not instantiated directly, but the media 233 * entity structure is inherited by (through embedding) other subsystem-specific 234 * structures. The media entity type identifies the type of the subclass 235 * structure that implements a media entity instance. 236 * 237 * This allows runtime type identification of media entities and safe casting to 238 * the correct object type. For instance, a media entity structure instance 239 * embedded in a v4l2_subdev structure instance will have the type 240 * %MEDIA_ENTITY_TYPE_V4L2_SUBDEV and can safely be cast to a &v4l2_subdev 241 * structure using the container_of() macro. 242 */ 243 enum media_entity_type { 244 MEDIA_ENTITY_TYPE_BASE, 245 MEDIA_ENTITY_TYPE_VIDEO_DEVICE, 246 MEDIA_ENTITY_TYPE_V4L2_SUBDEV, 247 }; 248 249 /** 250 * struct media_entity - A media entity graph object. 251 * 252 * @graph_obj: Embedded structure containing the media object common data. 253 * @name: Entity name. 254 * @obj_type: Type of the object that implements the media_entity. 255 * @function: Entity main function, as defined in 256 * :ref:`include/uapi/linux/media.h <media_header>` 257 * (seek for ``MEDIA_ENT_F_*``) 258 * @flags: Entity flags, as defined in 259 * :ref:`include/uapi/linux/media.h <media_header>` 260 * (seek for ``MEDIA_ENT_FL_*``) 261 * @num_pads: Number of sink and source pads. 262 * @num_links: Total number of links, forward and back, enabled and disabled. 263 * @num_backlinks: Number of backlinks 264 * @internal_idx: An unique internal entity specific number. The numbers are 265 * re-used if entities are unregistered or registered again. 266 * @pads: Pads array with the size defined by @num_pads. 267 * @links: List of data links. 268 * @ops: Entity operations. 269 * @stream_count: Stream count for the entity. 270 * @use_count: Use count for the entity. 271 * @pipe: Pipeline this entity belongs to. 272 * @info: Union with devnode information. Kept just for backward 273 * compatibility. 274 * @info.dev: Contains device major and minor info. 275 * @info.dev.major: device node major, if the device is a devnode. 276 * @info.dev.minor: device node minor, if the device is a devnode. 277 * @major: Devnode major number (zero if not applicable). Kept just 278 * for backward compatibility. 279 * @minor: Devnode minor number (zero if not applicable). Kept just 280 * for backward compatibility. 281 * 282 * .. note:: 283 * 284 * @stream_count and @use_count reference counts must never be 285 * negative, but are signed integers on purpose: a simple ``WARN_ON(<0)`` 286 * check can be used to detect reference count bugs that would make them 287 * negative. 288 */ 289 struct media_entity { 290 struct media_gobj graph_obj; /* must be first field in struct */ 291 const char *name; 292 enum media_entity_type obj_type; 293 u32 function; 294 unsigned long flags; 295 296 u16 num_pads; 297 u16 num_links; 298 u16 num_backlinks; 299 int internal_idx; 300 301 struct media_pad *pads; 302 struct list_head links; 303 304 const struct media_entity_operations *ops; 305 306 int stream_count; 307 int use_count; 308 309 struct media_pipeline *pipe; 310 311 union { 312 struct { 313 u32 major; 314 u32 minor; 315 } dev; 316 } info; 317 }; 318 319 /** 320 * struct media_interface - A media interface graph object. 321 * 322 * @graph_obj: embedded graph object 323 * @links: List of links pointing to graph entities 324 * @type: Type of the interface as defined in 325 * :ref:`include/uapi/linux/media.h <media_header>` 326 * (seek for ``MEDIA_INTF_T_*``) 327 * @flags: Interface flags as defined in 328 * :ref:`include/uapi/linux/media.h <media_header>` 329 * (seek for ``MEDIA_INTF_FL_*``) 330 * 331 * .. note:: 332 * 333 * Currently, no flags for &media_interface is defined. 334 */ 335 struct media_interface { 336 struct media_gobj graph_obj; 337 struct list_head links; 338 u32 type; 339 u32 flags; 340 }; 341 342 /** 343 * struct media_intf_devnode - A media interface via a device node. 344 * 345 * @intf: embedded interface object 346 * @major: Major number of a device node 347 * @minor: Minor number of a device node 348 */ 349 struct media_intf_devnode { 350 struct media_interface intf; 351 352 /* Should match the fields at media_v2_intf_devnode */ 353 u32 major; 354 u32 minor; 355 }; 356 357 /** 358 * media_entity_id() - return the media entity graph object id 359 * 360 * @entity: pointer to &media_entity 361 */ 362 static inline u32 media_entity_id(struct media_entity *entity) 363 { 364 return entity->graph_obj.id; 365 } 366 367 /** 368 * media_type() - return the media object type 369 * 370 * @gobj: Pointer to the struct &media_gobj graph object 371 */ 372 static inline enum media_gobj_type media_type(struct media_gobj *gobj) 373 { 374 return gobj->id >> MEDIA_BITS_PER_ID; 375 } 376 377 /** 378 * media_id() - return the media object ID 379 * 380 * @gobj: Pointer to the struct &media_gobj graph object 381 */ 382 static inline u32 media_id(struct media_gobj *gobj) 383 { 384 return gobj->id & MEDIA_ID_MASK; 385 } 386 387 /** 388 * media_gobj_gen_id() - encapsulates type and ID on at the object ID 389 * 390 * @type: object type as define at enum &media_gobj_type. 391 * @local_id: next ID, from struct &media_device.id. 392 */ 393 static inline u32 media_gobj_gen_id(enum media_gobj_type type, u64 local_id) 394 { 395 u32 id; 396 397 id = type << MEDIA_BITS_PER_ID; 398 id |= local_id & MEDIA_ID_MASK; 399 400 return id; 401 } 402 403 /** 404 * is_media_entity_v4l2_video_device() - Check if the entity is a video_device 405 * @entity: pointer to entity 406 * 407 * Return: %true if the entity is an instance of a video_device object and can 408 * safely be cast to a struct video_device using the container_of() macro, or 409 * %false otherwise. 410 */ 411 static inline bool is_media_entity_v4l2_video_device(struct media_entity *entity) 412 { 413 return entity && entity->obj_type == MEDIA_ENTITY_TYPE_VIDEO_DEVICE; 414 } 415 416 /** 417 * is_media_entity_v4l2_subdev() - Check if the entity is a v4l2_subdev 418 * @entity: pointer to entity 419 * 420 * Return: %true if the entity is an instance of a &v4l2_subdev object and can 421 * safely be cast to a struct &v4l2_subdev using the container_of() macro, or 422 * %false otherwise. 423 */ 424 static inline bool is_media_entity_v4l2_subdev(struct media_entity *entity) 425 { 426 return entity && entity->obj_type == MEDIA_ENTITY_TYPE_V4L2_SUBDEV; 427 } 428 429 /** 430 * __media_entity_enum_init - Initialise an entity enumeration 431 * 432 * @ent_enum: Entity enumeration to be initialised 433 * @idx_max: Maximum number of entities in the enumeration 434 * 435 * Return: Returns zero on success or a negative error code. 436 */ 437 __must_check int __media_entity_enum_init(struct media_entity_enum *ent_enum, 438 int idx_max); 439 440 /** 441 * media_entity_enum_cleanup - Release resources of an entity enumeration 442 * 443 * @ent_enum: Entity enumeration to be released 444 */ 445 void media_entity_enum_cleanup(struct media_entity_enum *ent_enum); 446 447 /** 448 * media_entity_enum_zero - Clear the entire enum 449 * 450 * @ent_enum: Entity enumeration to be cleared 451 */ 452 static inline void media_entity_enum_zero(struct media_entity_enum *ent_enum) 453 { 454 bitmap_zero(ent_enum->bmap, ent_enum->idx_max); 455 } 456 457 /** 458 * media_entity_enum_set - Mark a single entity in the enum 459 * 460 * @ent_enum: Entity enumeration 461 * @entity: Entity to be marked 462 */ 463 static inline void media_entity_enum_set(struct media_entity_enum *ent_enum, 464 struct media_entity *entity) 465 { 466 if (WARN_ON(entity->internal_idx >= ent_enum->idx_max)) 467 return; 468 469 __set_bit(entity->internal_idx, ent_enum->bmap); 470 } 471 472 /** 473 * media_entity_enum_clear - Unmark a single entity in the enum 474 * 475 * @ent_enum: Entity enumeration 476 * @entity: Entity to be unmarked 477 */ 478 static inline void media_entity_enum_clear(struct media_entity_enum *ent_enum, 479 struct media_entity *entity) 480 { 481 if (WARN_ON(entity->internal_idx >= ent_enum->idx_max)) 482 return; 483 484 __clear_bit(entity->internal_idx, ent_enum->bmap); 485 } 486 487 /** 488 * media_entity_enum_test - Test whether the entity is marked 489 * 490 * @ent_enum: Entity enumeration 491 * @entity: Entity to be tested 492 * 493 * Returns %true if the entity was marked. 494 */ 495 static inline bool media_entity_enum_test(struct media_entity_enum *ent_enum, 496 struct media_entity *entity) 497 { 498 if (WARN_ON(entity->internal_idx >= ent_enum->idx_max)) 499 return true; 500 501 return test_bit(entity->internal_idx, ent_enum->bmap); 502 } 503 504 /** 505 * media_entity_enum_test_and_set - Test whether the entity is marked, 506 * and mark it 507 * 508 * @ent_enum: Entity enumeration 509 * @entity: Entity to be tested 510 * 511 * Returns %true if the entity was marked, and mark it before doing so. 512 */ 513 static inline bool 514 media_entity_enum_test_and_set(struct media_entity_enum *ent_enum, 515 struct media_entity *entity) 516 { 517 if (WARN_ON(entity->internal_idx >= ent_enum->idx_max)) 518 return true; 519 520 return __test_and_set_bit(entity->internal_idx, ent_enum->bmap); 521 } 522 523 /** 524 * media_entity_enum_empty - Test whether the entire enum is empty 525 * 526 * @ent_enum: Entity enumeration 527 * 528 * Return: %true if the entity was empty. 529 */ 530 static inline bool media_entity_enum_empty(struct media_entity_enum *ent_enum) 531 { 532 return bitmap_empty(ent_enum->bmap, ent_enum->idx_max); 533 } 534 535 /** 536 * media_entity_enum_intersects - Test whether two enums intersect 537 * 538 * @ent_enum1: First entity enumeration 539 * @ent_enum2: Second entity enumeration 540 * 541 * Return: %true if entity enumerations @ent_enum1 and @ent_enum2 intersect, 542 * otherwise %false. 543 */ 544 static inline bool media_entity_enum_intersects( 545 struct media_entity_enum *ent_enum1, 546 struct media_entity_enum *ent_enum2) 547 { 548 WARN_ON(ent_enum1->idx_max != ent_enum2->idx_max); 549 550 return bitmap_intersects(ent_enum1->bmap, ent_enum2->bmap, 551 min(ent_enum1->idx_max, ent_enum2->idx_max)); 552 } 553 554 /** 555 * gobj_to_entity - returns the struct &media_entity pointer from the 556 * @gobj contained on it. 557 * 558 * @gobj: Pointer to the struct &media_gobj graph object 559 */ 560 #define gobj_to_entity(gobj) \ 561 container_of(gobj, struct media_entity, graph_obj) 562 563 /** 564 * gobj_to_pad - returns the struct &media_pad pointer from the 565 * @gobj contained on it. 566 * 567 * @gobj: Pointer to the struct &media_gobj graph object 568 */ 569 #define gobj_to_pad(gobj) \ 570 container_of(gobj, struct media_pad, graph_obj) 571 572 /** 573 * gobj_to_link - returns the struct &media_link pointer from the 574 * @gobj contained on it. 575 * 576 * @gobj: Pointer to the struct &media_gobj graph object 577 */ 578 #define gobj_to_link(gobj) \ 579 container_of(gobj, struct media_link, graph_obj) 580 581 /** 582 * gobj_to_intf - returns the struct &media_interface pointer from the 583 * @gobj contained on it. 584 * 585 * @gobj: Pointer to the struct &media_gobj graph object 586 */ 587 #define gobj_to_intf(gobj) \ 588 container_of(gobj, struct media_interface, graph_obj) 589 590 /** 591 * intf_to_devnode - returns the struct media_intf_devnode pointer from the 592 * @intf contained on it. 593 * 594 * @intf: Pointer to struct &media_intf_devnode 595 */ 596 #define intf_to_devnode(intf) \ 597 container_of(intf, struct media_intf_devnode, intf) 598 599 /** 600 * media_gobj_create - Initialize a graph object 601 * 602 * @mdev: Pointer to the &media_device that contains the object 603 * @type: Type of the object 604 * @gobj: Pointer to the struct &media_gobj graph object 605 * 606 * This routine initializes the embedded struct &media_gobj inside a 607 * media graph object. It is called automatically if ``media_*_create`` 608 * function calls are used. However, if the object (entity, link, pad, 609 * interface) is embedded on some other object, this function should be 610 * called before registering the object at the media controller. 611 */ 612 void media_gobj_create(struct media_device *mdev, 613 enum media_gobj_type type, 614 struct media_gobj *gobj); 615 616 /** 617 * media_gobj_destroy - Stop using a graph object on a media device 618 * 619 * @gobj: Pointer to the struct &media_gobj graph object 620 * 621 * This should be called by all routines like media_device_unregister() 622 * that remove/destroy media graph objects. 623 */ 624 void media_gobj_destroy(struct media_gobj *gobj); 625 626 /** 627 * media_entity_pads_init() - Initialize the entity pads 628 * 629 * @entity: entity where the pads belong 630 * @num_pads: total number of sink and source pads 631 * @pads: Array of @num_pads pads. 632 * 633 * The pads array is managed by the entity driver and passed to 634 * media_entity_pads_init() where its pointer will be stored in the 635 * &media_entity structure. 636 * 637 * If no pads are needed, drivers could either directly fill 638 * &media_entity->num_pads with 0 and &media_entity->pads with %NULL or call 639 * this function that will do the same. 640 * 641 * As the number of pads is known in advance, the pads array is not allocated 642 * dynamically but is managed by the entity driver. Most drivers will embed the 643 * pads array in a driver-specific structure, avoiding dynamic allocation. 644 * 645 * Drivers must set the direction of every pad in the pads array before calling 646 * media_entity_pads_init(). The function will initialize the other pads fields. 647 */ 648 int media_entity_pads_init(struct media_entity *entity, u16 num_pads, 649 struct media_pad *pads); 650 651 /** 652 * media_entity_cleanup() - free resources associated with an entity 653 * 654 * @entity: entity where the pads belong 655 * 656 * This function must be called during the cleanup phase after unregistering 657 * the entity (currently, it does nothing). 658 */ 659 #if IS_ENABLED(CONFIG_MEDIA_CONTROLLER) 660 static inline void media_entity_cleanup(struct media_entity *entity) {} 661 #else 662 #define media_entity_cleanup(entity) do { } while (false) 663 #endif 664 665 /** 666 * media_get_pad_index() - retrieves a pad index from an entity 667 * 668 * @entity: entity where the pads belong 669 * @is_sink: true if the pad is a sink, false if it is a source 670 * @sig_type: type of signal of the pad to be search 671 * 672 * This helper function finds the first pad index inside an entity that 673 * satisfies both @is_sink and @sig_type conditions. 674 * 675 * Return: 676 * 677 * On success, return the pad number. If the pad was not found or the media 678 * entity is a NULL pointer, return -EINVAL. 679 */ 680 int media_get_pad_index(struct media_entity *entity, bool is_sink, 681 enum media_pad_signal_type sig_type); 682 683 /** 684 * media_create_pad_link() - creates a link between two entities. 685 * 686 * @source: pointer to &media_entity of the source pad. 687 * @source_pad: number of the source pad in the pads array 688 * @sink: pointer to &media_entity of the sink pad. 689 * @sink_pad: number of the sink pad in the pads array. 690 * @flags: Link flags, as defined in 691 * :ref:`include/uapi/linux/media.h <media_header>` 692 * ( seek for ``MEDIA_LNK_FL_*``) 693 * 694 * Valid values for flags: 695 * 696 * %MEDIA_LNK_FL_ENABLED 697 * Indicates that the link is enabled and can be used to transfer media data. 698 * When two or more links target a sink pad, only one of them can be 699 * enabled at a time. 700 * 701 * %MEDIA_LNK_FL_IMMUTABLE 702 * Indicates that the link enabled state can't be modified at runtime. If 703 * %MEDIA_LNK_FL_IMMUTABLE is set, then %MEDIA_LNK_FL_ENABLED must also be 704 * set, since an immutable link is always enabled. 705 * 706 * .. note:: 707 * 708 * Before calling this function, media_entity_pads_init() and 709 * media_device_register_entity() should be called previously for both ends. 710 */ 711 __must_check int media_create_pad_link(struct media_entity *source, 712 u16 source_pad, struct media_entity *sink, 713 u16 sink_pad, u32 flags); 714 715 /** 716 * media_create_pad_links() - creates a link between two entities. 717 * 718 * @mdev: Pointer to the media_device that contains the object 719 * @source_function: Function of the source entities. Used only if @source is 720 * NULL. 721 * @source: pointer to &media_entity of the source pad. If NULL, it will use 722 * all entities that matches the @sink_function. 723 * @source_pad: number of the source pad in the pads array 724 * @sink_function: Function of the sink entities. Used only if @sink is NULL. 725 * @sink: pointer to &media_entity of the sink pad. If NULL, it will use 726 * all entities that matches the @sink_function. 727 * @sink_pad: number of the sink pad in the pads array. 728 * @flags: Link flags, as defined in include/uapi/linux/media.h. 729 * @allow_both_undefined: if %true, then both @source and @sink can be NULL. 730 * In such case, it will create a crossbar between all entities that 731 * matches @source_function to all entities that matches @sink_function. 732 * If %false, it will return 0 and won't create any link if both @source 733 * and @sink are NULL. 734 * 735 * Valid values for flags: 736 * 737 * A %MEDIA_LNK_FL_ENABLED flag indicates that the link is enabled and can be 738 * used to transfer media data. If multiple links are created and this 739 * flag is passed as an argument, only the first created link will have 740 * this flag. 741 * 742 * A %MEDIA_LNK_FL_IMMUTABLE flag indicates that the link enabled state can't 743 * be modified at runtime. If %MEDIA_LNK_FL_IMMUTABLE is set, then 744 * %MEDIA_LNK_FL_ENABLED must also be set since an immutable link is 745 * always enabled. 746 * 747 * It is common for some devices to have multiple source and/or sink entities 748 * of the same type that should be linked. While media_create_pad_link() 749 * creates link by link, this function is meant to allow 1:n, n:1 and even 750 * cross-bar (n:n) links. 751 * 752 * .. note:: 753 * 754 * Before calling this function, media_entity_pads_init() and 755 * media_device_register_entity() should be called previously for the 756 * entities to be linked. 757 */ 758 int media_create_pad_links(const struct media_device *mdev, 759 const u32 source_function, 760 struct media_entity *source, 761 const u16 source_pad, 762 const u32 sink_function, 763 struct media_entity *sink, 764 const u16 sink_pad, 765 u32 flags, 766 const bool allow_both_undefined); 767 768 void __media_entity_remove_links(struct media_entity *entity); 769 770 /** 771 * media_entity_remove_links() - remove all links associated with an entity 772 * 773 * @entity: pointer to &media_entity 774 * 775 * .. note:: 776 * 777 * This is called automatically when an entity is unregistered via 778 * media_device_register_entity(). 779 */ 780 void media_entity_remove_links(struct media_entity *entity); 781 782 /** 783 * __media_entity_setup_link - Configure a media link without locking 784 * @link: The link being configured 785 * @flags: Link configuration flags 786 * 787 * The bulk of link setup is handled by the two entities connected through the 788 * link. This function notifies both entities of the link configuration change. 789 * 790 * If the link is immutable or if the current and new configuration are 791 * identical, return immediately. 792 * 793 * The user is expected to hold link->source->parent->mutex. If not, 794 * media_entity_setup_link() should be used instead. 795 */ 796 int __media_entity_setup_link(struct media_link *link, u32 flags); 797 798 /** 799 * media_entity_setup_link() - changes the link flags properties in runtime 800 * 801 * @link: pointer to &media_link 802 * @flags: the requested new link flags 803 * 804 * The only configurable property is the %MEDIA_LNK_FL_ENABLED link flag 805 * flag to enable/disable a link. Links marked with the 806 * %MEDIA_LNK_FL_IMMUTABLE link flag can not be enabled or disabled. 807 * 808 * When a link is enabled or disabled, the media framework calls the 809 * link_setup operation for the two entities at the source and sink of the 810 * link, in that order. If the second link_setup call fails, another 811 * link_setup call is made on the first entity to restore the original link 812 * flags. 813 * 814 * Media device drivers can be notified of link setup operations by setting the 815 * &media_device.link_notify pointer to a callback function. If provided, the 816 * notification callback will be called before enabling and after disabling 817 * links. 818 * 819 * Entity drivers must implement the link_setup operation if any of their links 820 * is non-immutable. The operation must either configure the hardware or store 821 * the configuration information to be applied later. 822 * 823 * Link configuration must not have any side effect on other links. If an 824 * enabled link at a sink pad prevents another link at the same pad from 825 * being enabled, the link_setup operation must return %-EBUSY and can't 826 * implicitly disable the first enabled link. 827 * 828 * .. note:: 829 * 830 * The valid values of the flags for the link is the same as described 831 * on media_create_pad_link(), for pad to pad links or the same as described 832 * on media_create_intf_link(), for interface to entity links. 833 */ 834 int media_entity_setup_link(struct media_link *link, u32 flags); 835 836 /** 837 * media_entity_find_link - Find a link between two pads 838 * @source: Source pad 839 * @sink: Sink pad 840 * 841 * Return: returns a pointer to the link between the two entities. If no 842 * such link exists, return %NULL. 843 */ 844 struct media_link *media_entity_find_link(struct media_pad *source, 845 struct media_pad *sink); 846 847 /** 848 * media_entity_remote_pad - Find the pad at the remote end of a link 849 * @pad: Pad at the local end of the link 850 * 851 * Search for a remote pad connected to the given pad by iterating over all 852 * links originating or terminating at that pad until an enabled link is found. 853 * 854 * Return: returns a pointer to the pad at the remote end of the first found 855 * enabled link, or %NULL if no enabled link has been found. 856 */ 857 struct media_pad *media_entity_remote_pad(const struct media_pad *pad); 858 859 /** 860 * media_entity_get_fwnode_pad - Get pad number from fwnode 861 * 862 * @entity: The entity 863 * @fwnode: Pointer to the fwnode_handle which should be used to find the pad 864 * @direction_flags: Expected direction of the pad, as defined in 865 * :ref:`include/uapi/linux/media.h <media_header>` 866 * (seek for ``MEDIA_PAD_FL_*``) 867 * 868 * This function can be used to resolve the media pad number from 869 * a fwnode. This is useful for devices which use more complex 870 * mappings of media pads. 871 * 872 * If the entity does not implement the get_fwnode_pad() operation 873 * then this function searches the entity for the first pad that 874 * matches the @direction_flags. 875 * 876 * Return: returns the pad number on success or a negative error code. 877 */ 878 int media_entity_get_fwnode_pad(struct media_entity *entity, 879 struct fwnode_handle *fwnode, 880 unsigned long direction_flags); 881 882 /** 883 * media_graph_walk_init - Allocate resources used by graph walk. 884 * 885 * @graph: Media graph structure that will be used to walk the graph 886 * @mdev: Pointer to the &media_device that contains the object 887 */ 888 __must_check int media_graph_walk_init( 889 struct media_graph *graph, struct media_device *mdev); 890 891 /** 892 * media_graph_walk_cleanup - Release resources used by graph walk. 893 * 894 * @graph: Media graph structure that will be used to walk the graph 895 */ 896 void media_graph_walk_cleanup(struct media_graph *graph); 897 898 /** 899 * media_graph_walk_start - Start walking the media graph at a 900 * given entity 901 * 902 * @graph: Media graph structure that will be used to walk the graph 903 * @entity: Starting entity 904 * 905 * Before using this function, media_graph_walk_init() must be 906 * used to allocate resources used for walking the graph. This 907 * function initializes the graph traversal structure to walk the 908 * entities graph starting at the given entity. The traversal 909 * structure must not be modified by the caller during graph 910 * traversal. After the graph walk, the resources must be released 911 * using media_graph_walk_cleanup(). 912 */ 913 void media_graph_walk_start(struct media_graph *graph, 914 struct media_entity *entity); 915 916 /** 917 * media_graph_walk_next - Get the next entity in the graph 918 * @graph: Media graph structure 919 * 920 * Perform a depth-first traversal of the given media entities graph. 921 * 922 * The graph structure must have been previously initialized with a call to 923 * media_graph_walk_start(). 924 * 925 * Return: returns the next entity in the graph or %NULL if the whole graph 926 * have been traversed. 927 */ 928 struct media_entity *media_graph_walk_next(struct media_graph *graph); 929 930 /** 931 * media_pipeline_start - Mark a pipeline as streaming 932 * @entity: Starting entity 933 * @pipe: Media pipeline to be assigned to all entities in the pipeline. 934 * 935 * Mark all entities connected to a given entity through enabled links, either 936 * directly or indirectly, as streaming. The given pipeline object is assigned 937 * to every entity in the pipeline and stored in the media_entity pipe field. 938 * 939 * Calls to this function can be nested, in which case the same number of 940 * media_pipeline_stop() calls will be required to stop streaming. The 941 * pipeline pointer must be identical for all nested calls to 942 * media_pipeline_start(). 943 */ 944 __must_check int media_pipeline_start(struct media_entity *entity, 945 struct media_pipeline *pipe); 946 /** 947 * __media_pipeline_start - Mark a pipeline as streaming 948 * 949 * @entity: Starting entity 950 * @pipe: Media pipeline to be assigned to all entities in the pipeline. 951 * 952 * ..note:: This is the non-locking version of media_pipeline_start() 953 */ 954 __must_check int __media_pipeline_start(struct media_entity *entity, 955 struct media_pipeline *pipe); 956 957 /** 958 * media_pipeline_stop - Mark a pipeline as not streaming 959 * @entity: Starting entity 960 * 961 * Mark all entities connected to a given entity through enabled links, either 962 * directly or indirectly, as not streaming. The media_entity pipe field is 963 * reset to %NULL. 964 * 965 * If multiple calls to media_pipeline_start() have been made, the same 966 * number of calls to this function are required to mark the pipeline as not 967 * streaming. 968 */ 969 void media_pipeline_stop(struct media_entity *entity); 970 971 /** 972 * __media_pipeline_stop - Mark a pipeline as not streaming 973 * 974 * @entity: Starting entity 975 * 976 * .. note:: This is the non-locking version of media_pipeline_stop() 977 */ 978 void __media_pipeline_stop(struct media_entity *entity); 979 980 /** 981 * media_devnode_create() - creates and initializes a device node interface 982 * 983 * @mdev: pointer to struct &media_device 984 * @type: type of the interface, as given by 985 * :ref:`include/uapi/linux/media.h <media_header>` 986 * ( seek for ``MEDIA_INTF_T_*``) macros. 987 * @flags: Interface flags, as defined in 988 * :ref:`include/uapi/linux/media.h <media_header>` 989 * ( seek for ``MEDIA_INTF_FL_*``) 990 * @major: Device node major number. 991 * @minor: Device node minor number. 992 * 993 * Return: if succeeded, returns a pointer to the newly allocated 994 * &media_intf_devnode pointer. 995 * 996 * .. note:: 997 * 998 * Currently, no flags for &media_interface is defined. 999 */ 1000 struct media_intf_devnode * 1001 __must_check media_devnode_create(struct media_device *mdev, 1002 u32 type, u32 flags, 1003 u32 major, u32 minor); 1004 /** 1005 * media_devnode_remove() - removes a device node interface 1006 * 1007 * @devnode: pointer to &media_intf_devnode to be freed. 1008 * 1009 * When a device node interface is removed, all links to it are automatically 1010 * removed. 1011 */ 1012 void media_devnode_remove(struct media_intf_devnode *devnode); 1013 struct media_link * 1014 1015 /** 1016 * media_create_intf_link() - creates a link between an entity and an interface 1017 * 1018 * @entity: pointer to %media_entity 1019 * @intf: pointer to %media_interface 1020 * @flags: Link flags, as defined in 1021 * :ref:`include/uapi/linux/media.h <media_header>` 1022 * ( seek for ``MEDIA_LNK_FL_*``) 1023 * 1024 * 1025 * Valid values for flags: 1026 * 1027 * %MEDIA_LNK_FL_ENABLED 1028 * Indicates that the interface is connected to the entity hardware. 1029 * That's the default value for interfaces. An interface may be disabled if 1030 * the hardware is busy due to the usage of some other interface that it is 1031 * currently controlling the hardware. 1032 * 1033 * A typical example is an hybrid TV device that handle only one type of 1034 * stream on a given time. So, when the digital TV is streaming, 1035 * the V4L2 interfaces won't be enabled, as such device is not able to 1036 * also stream analog TV or radio. 1037 * 1038 * .. note:: 1039 * 1040 * Before calling this function, media_devnode_create() should be called for 1041 * the interface and media_device_register_entity() should be called for the 1042 * interface that will be part of the link. 1043 */ 1044 __must_check media_create_intf_link(struct media_entity *entity, 1045 struct media_interface *intf, 1046 u32 flags); 1047 /** 1048 * __media_remove_intf_link() - remove a single interface link 1049 * 1050 * @link: pointer to &media_link. 1051 * 1052 * .. note:: This is an unlocked version of media_remove_intf_link() 1053 */ 1054 void __media_remove_intf_link(struct media_link *link); 1055 1056 /** 1057 * media_remove_intf_link() - remove a single interface link 1058 * 1059 * @link: pointer to &media_link. 1060 * 1061 * .. note:: Prefer to use this one, instead of __media_remove_intf_link() 1062 */ 1063 void media_remove_intf_link(struct media_link *link); 1064 1065 /** 1066 * __media_remove_intf_links() - remove all links associated with an interface 1067 * 1068 * @intf: pointer to &media_interface 1069 * 1070 * .. note:: This is an unlocked version of media_remove_intf_links(). 1071 */ 1072 void __media_remove_intf_links(struct media_interface *intf); 1073 1074 /** 1075 * media_remove_intf_links() - remove all links associated with an interface 1076 * 1077 * @intf: pointer to &media_interface 1078 * 1079 * .. note:: 1080 * 1081 * #) This is called automatically when an entity is unregistered via 1082 * media_device_register_entity() and by media_devnode_remove(). 1083 * 1084 * #) Prefer to use this one, instead of __media_remove_intf_links(). 1085 */ 1086 void media_remove_intf_links(struct media_interface *intf); 1087 1088 /** 1089 * media_entity_call - Calls a struct media_entity_operations operation on 1090 * an entity 1091 * 1092 * @entity: entity where the @operation will be called 1093 * @operation: type of the operation. Should be the name of a member of 1094 * struct &media_entity_operations. 1095 * 1096 * This helper function will check if @operation is not %NULL. On such case, 1097 * it will issue a call to @operation\(@entity, @args\). 1098 */ 1099 1100 #define media_entity_call(entity, operation, args...) \ 1101 (((entity)->ops && (entity)->ops->operation) ? \ 1102 (entity)->ops->operation((entity) , ##args) : -ENOIOCTLCMD) 1103 1104 #endif 1105