4 * Copyright (C) 2010 Nokia Corporation
6 * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
7 * Sakari Ailus <sakari.ailus@iki.fi>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 #ifndef _MEDIA_ENTITY_H
24 #define _MEDIA_ENTITY_H
26 #include <linux/bitmap.h>
27 #include <linux/kernel.h>
28 #include <linux/list.h>
29 #include <linux/media.h>
31 /* Enums used internally at the media controller to represent graphs */
34 * enum media_gobj_type - type of a graph object
36 * @MEDIA_GRAPH_ENTITY: Identify a media entity
37 * @MEDIA_GRAPH_PAD: Identify a media pad
38 * @MEDIA_GRAPH_LINK: Identify a media link
39 * @MEDIA_GRAPH_INTF_DEVNODE: Identify a media Kernel API interface via
42 enum media_gobj_type
{
46 MEDIA_GRAPH_INTF_DEVNODE
,
49 #define MEDIA_BITS_PER_TYPE 8
50 #define MEDIA_BITS_PER_LOCAL_ID (32 - MEDIA_BITS_PER_TYPE)
51 #define MEDIA_LOCAL_ID_MASK GENMASK(MEDIA_BITS_PER_LOCAL_ID - 1, 0)
53 /* Structs to represent the objects that belong to a media graph */
56 * struct media_gobj - Define a graph object.
58 * @mdev: Pointer to the struct media_device that owns the object
59 * @id: Non-zero object ID identifier. The ID should be unique
60 * inside a media_device, as it is composed by
61 * MEDIA_BITS_PER_TYPE to store the type plus
62 * MEDIA_BITS_PER_LOCAL_ID to store a per-type ID
63 * (called as "local ID").
64 * @list: List entry stored in one of the per-type mdev object lists
66 * All objects on the media graph should have this struct embedded
69 struct media_device
*mdev
;
71 struct list_head list
;
74 #define MEDIA_ENTITY_ENUM_MAX_DEPTH 16
75 #define MEDIA_ENTITY_ENUM_MAX_ID 64
78 * The number of pads can't be bigger than the number of entities,
79 * as the worse-case scenario is to have one entity linked up to
80 * MEDIA_ENTITY_ENUM_MAX_ID - 1 entities.
82 #define MEDIA_ENTITY_MAX_PADS (MEDIA_ENTITY_ENUM_MAX_ID - 1)
85 * struct media_entity_enum - An enumeration of media entities.
87 * @prealloc_bmap: Pre-allocated space reserved for media entities if the
88 * total number of entities does not exceed
89 * MEDIA_ENTITY_ENUM_MAX_ID.
90 * @bmap: Bit map in which each bit represents one entity at struct
91 * media_entity->internal_idx.
92 * @idx_max: Number of bits in bmap
94 struct media_entity_enum
{
95 DECLARE_BITMAP(prealloc_bmap
, MEDIA_ENTITY_ENUM_MAX_ID
);
100 struct media_pipeline
{
104 * struct media_link - A link object part of a media graph.
106 * @graph_obj: Embedded structure containing the media object common data
107 * @list: Linked list associated with an entity or an interface that
109 * @gobj0: Part of a union. Used to get the pointer for the first
110 * graph_object of the link.
111 * @source: Part of a union. Used only if the first object (gobj0) is
112 * a pad. In that case, it represents the source pad.
113 * @intf: Part of a union. Used only if the first object (gobj0) is
115 * @gobj1: Part of a union. Used to get the pointer for the second
116 * graph_object of the link.
117 * @source: Part of a union. Used only if the second object (gobj1) is
118 * a pad. In that case, it represents the sink pad.
119 * @entity: Part of a union. Used only if the second object (gobj1) is
121 * @reverse: Pointer to the link for the reverse direction of a pad to pad
123 * @flags: Link flags, as defined in uapi/media.h (MEDIA_LNK_FL_*)
124 * @is_backlink: Indicate if the link is a backlink.
127 struct media_gobj graph_obj
;
128 struct list_head list
;
130 struct media_gobj
*gobj0
;
131 struct media_pad
*source
;
132 struct media_interface
*intf
;
135 struct media_gobj
*gobj1
;
136 struct media_pad
*sink
;
137 struct media_entity
*entity
;
139 struct media_link
*reverse
;
145 * struct media_pad - A media pad graph object.
147 * @graph_obj: Embedded structure containing the media object common data
148 * @entity: Entity this pad belongs to
149 * @index: Pad index in the entity pads array, numbered from 0 to n
150 * @flags: Pad flags, as defined in uapi/media.h (MEDIA_PAD_FL_*)
153 struct media_gobj graph_obj
; /* must be first field in struct */
154 struct media_entity
*entity
;
160 * struct media_entity_operations - Media entity operations
161 * @link_setup: Notify the entity of link changes. The operation can
162 * return an error, in which case link setup will be
163 * cancelled. Optional.
164 * @link_validate: Return whether a link is valid from the entity point of
165 * view. The media_entity_pipeline_start() function
166 * validates all links by calling this operation. Optional.
168 struct media_entity_operations
{
169 int (*link_setup
)(struct media_entity
*entity
,
170 const struct media_pad
*local
,
171 const struct media_pad
*remote
, u32 flags
);
172 int (*link_validate
)(struct media_link
*link
);
176 * struct media_entity - A media entity graph object.
178 * @graph_obj: Embedded structure containing the media object common data.
179 * @name: Entity name.
180 * @function: Entity main function, as defined in uapi/media.h
182 * @flags: Entity flags, as defined in uapi/media.h (MEDIA_ENT_FL_*)
183 * @num_pads: Number of sink and source pads.
184 * @num_links: Total number of links, forward and back, enabled and disabled.
185 * @num_backlinks: Number of backlinks
186 * @internal_idx: An unique internal entity specific number. The numbers are
187 * re-used if entities are unregistered or registered again.
188 * @pads: Pads array with the size defined by @num_pads.
189 * @links: List of data links.
190 * @ops: Entity operations.
191 * @stream_count: Stream count for the entity.
192 * @use_count: Use count for the entity.
193 * @pipe: Pipeline this entity belongs to.
194 * @info: Union with devnode information. Kept just for backward
196 * @major: Devnode major number (zero if not applicable). Kept just
197 * for backward compatibility.
198 * @minor: Devnode minor number (zero if not applicable). Kept just
199 * for backward compatibility.
201 * NOTE: @stream_count and @use_count reference counts must never be
202 * negative, but are signed integers on purpose: a simple WARN_ON(<0) check
203 * can be used to detect reference count bugs that would make them negative.
205 struct media_entity
{
206 struct media_gobj graph_obj
; /* must be first field in struct */
216 struct media_pad
*pads
;
217 struct list_head links
;
219 const struct media_entity_operations
*ops
;
221 /* Reference counts must never be negative, but are signed integers on
222 * purpose: a simple WARN_ON(<0) check can be used to detect reference
223 * count bugs that would make them negative.
228 struct media_pipeline
*pipe
;
239 * struct media_interface - A media interface graph object.
241 * @graph_obj: embedded graph object
242 * @links: List of links pointing to graph entities
243 * @type: Type of the interface as defined in the
244 * uapi/media/media.h header, e. g.
246 * @flags: Interface flags as defined in uapi/media/media.h
248 struct media_interface
{
249 struct media_gobj graph_obj
;
250 struct list_head links
;
256 * struct media_intf_devnode - A media interface via a device node.
258 * @intf: embedded interface object
259 * @major: Major number of a device node
260 * @minor: Minor number of a device node
262 struct media_intf_devnode
{
263 struct media_interface intf
;
265 /* Should match the fields at media_v2_intf_devnode */
271 * media_entity_id() - return the media entity graph object id
273 * @entity: pointer to entity
275 static inline u32
media_entity_id(struct media_entity
*entity
)
277 return entity
->graph_obj
.id
;
281 * media_type() - return the media object type
283 * @gobj: pointer to the media graph object
285 static inline enum media_gobj_type
media_type(struct media_gobj
*gobj
)
287 return gobj
->id
>> MEDIA_BITS_PER_LOCAL_ID
;
290 static inline u32
media_localid(struct media_gobj
*gobj
)
292 return gobj
->id
& MEDIA_LOCAL_ID_MASK
;
295 static inline u32
media_gobj_gen_id(enum media_gobj_type type
, u32 local_id
)
299 id
= type
<< MEDIA_BITS_PER_LOCAL_ID
;
300 id
|= local_id
& MEDIA_LOCAL_ID_MASK
;
306 * is_media_entity_v4l2_io() - identify if the entity main function
309 * @entity: pointer to entity
311 * Return: true if the entity main function is one of the V4L2 I/O types
312 * (video, VBI or SDR radio); false otherwise.
314 static inline bool is_media_entity_v4l2_io(struct media_entity
*entity
)
319 switch (entity
->function
) {
320 case MEDIA_ENT_F_IO_V4L
:
321 case MEDIA_ENT_F_IO_VBI
:
322 case MEDIA_ENT_F_IO_SWRADIO
:
330 * is_media_entity_v4l2_subdev - return true if the entity main function is
331 * associated with the V4L2 API subdev usage
333 * @entity: pointer to entity
335 * This is an ancillary function used by subdev-based V4L2 drivers.
336 * It checks if the entity function is one of functions used by a V4L2 subdev,
337 * e. g. camera-relatef functions, analog TV decoder, TV tuner, V4L2 DSPs.
339 static inline bool is_media_entity_v4l2_subdev(struct media_entity
*entity
)
344 switch (entity
->function
) {
345 case MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN
:
346 case MEDIA_ENT_F_CAM_SENSOR
:
347 case MEDIA_ENT_F_FLASH
:
348 case MEDIA_ENT_F_LENS
:
349 case MEDIA_ENT_F_ATV_DECODER
:
350 case MEDIA_ENT_F_TUNER
:
358 __must_check
int __media_entity_enum_init(struct media_entity_enum
*ent_enum
,
360 void media_entity_enum_cleanup(struct media_entity_enum
*e
);
363 * media_entity_enum_zero - Clear the entire enum
365 * @e: Entity enumeration to be cleared
367 static inline void media_entity_enum_zero(struct media_entity_enum
*ent_enum
)
369 bitmap_zero(ent_enum
->bmap
, ent_enum
->idx_max
);
373 * media_entity_enum_set - Mark a single entity in the enum
375 * @e: Entity enumeration
376 * @entity: Entity to be marked
378 static inline void media_entity_enum_set(struct media_entity_enum
*ent_enum
,
379 struct media_entity
*entity
)
381 if (WARN_ON(entity
->internal_idx
>= ent_enum
->idx_max
))
384 __set_bit(entity
->internal_idx
, ent_enum
->bmap
);
388 * media_entity_enum_clear - Unmark a single entity in the enum
390 * @e: Entity enumeration
391 * @entity: Entity to be unmarked
393 static inline void media_entity_enum_clear(struct media_entity_enum
*ent_enum
,
394 struct media_entity
*entity
)
396 if (WARN_ON(entity
->internal_idx
>= ent_enum
->idx_max
))
399 __clear_bit(entity
->internal_idx
, ent_enum
->bmap
);
403 * media_entity_enum_test - Test whether the entity is marked
405 * @e: Entity enumeration
406 * @entity: Entity to be tested
408 * Returns true if the entity was marked.
410 static inline bool media_entity_enum_test(struct media_entity_enum
*ent_enum
,
411 struct media_entity
*entity
)
413 if (WARN_ON(entity
->internal_idx
>= ent_enum
->idx_max
))
416 return test_bit(entity
->internal_idx
, ent_enum
->bmap
);
420 * media_entity_enum_test - Test whether the entity is marked, and mark it
422 * @e: Entity enumeration
423 * @entity: Entity to be tested
425 * Returns true if the entity was marked, and mark it before doing so.
427 static inline bool media_entity_enum_test_and_set(
428 struct media_entity_enum
*ent_enum
, struct media_entity
*entity
)
430 if (WARN_ON(entity
->internal_idx
>= ent_enum
->idx_max
))
433 return __test_and_set_bit(entity
->internal_idx
, ent_enum
->bmap
);
437 * media_entity_enum_test - Test whether the entire enum is empty
439 * @e: Entity enumeration
440 * @entity: Entity to be tested
442 * Returns true if the entity was marked.
444 static inline bool media_entity_enum_empty(struct media_entity_enum
*ent_enum
)
446 return bitmap_empty(ent_enum
->bmap
, ent_enum
->idx_max
);
450 * media_entity_enum_intersects - Test whether two enums intersect
452 * @e: First entity enumeration
453 * @f: Second entity enumeration
455 * Returns true if entity enumerations e and f intersect, otherwise false.
457 static inline bool media_entity_enum_intersects(
458 struct media_entity_enum
*ent_enum1
,
459 struct media_entity_enum
*ent_enum2
)
461 WARN_ON(ent_enum1
->idx_max
!= ent_enum2
->idx_max
);
463 return bitmap_intersects(ent_enum1
->bmap
, ent_enum2
->bmap
,
464 min(ent_enum1
->idx_max
, ent_enum2
->idx_max
));
467 struct media_entity_graph
{
469 struct media_entity
*entity
;
470 struct list_head
*link
;
471 } stack
[MEDIA_ENTITY_ENUM_MAX_DEPTH
];
473 DECLARE_BITMAP(entities
, MEDIA_ENTITY_ENUM_MAX_ID
);
477 #define gobj_to_entity(gobj) \
478 container_of(gobj, struct media_entity, graph_obj)
480 #define gobj_to_pad(gobj) \
481 container_of(gobj, struct media_pad, graph_obj)
483 #define gobj_to_link(gobj) \
484 container_of(gobj, struct media_link, graph_obj)
486 #define gobj_to_link(gobj) \
487 container_of(gobj, struct media_link, graph_obj)
489 #define gobj_to_pad(gobj) \
490 container_of(gobj, struct media_pad, graph_obj)
492 #define gobj_to_intf(gobj) \
493 container_of(gobj, struct media_interface, graph_obj)
495 #define intf_to_devnode(intf) \
496 container_of(intf, struct media_intf_devnode, intf)
499 * media_gobj_create - Initialize a graph object
501 * @mdev: Pointer to the media_device that contains the object
502 * @type: Type of the object
503 * @gobj: Pointer to the graph object
505 * This routine initializes the embedded struct media_gobj inside a
506 * media graph object. It is called automatically if media_*_create()
507 * calls are used. However, if the object (entity, link, pad, interface)
508 * is embedded on some other object, this function should be called before
509 * registering the object at the media controller.
511 void media_gobj_create(struct media_device
*mdev
,
512 enum media_gobj_type type
,
513 struct media_gobj
*gobj
);
516 * media_gobj_destroy - Stop using a graph object on a media device
518 * @gobj: Pointer to the graph object
520 * This should be called by all routines like media_device_unregister()
521 * that remove/destroy media graph objects.
523 void media_gobj_destroy(struct media_gobj
*gobj
);
526 * media_entity_pads_init() - Initialize the entity pads
528 * @entity: entity where the pads belong
529 * @num_pads: total number of sink and source pads
530 * @pads: Array of @num_pads pads.
532 * The pads array is managed by the entity driver and passed to
533 * media_entity_pads_init() where its pointer will be stored in the entity
536 * If no pads are needed, drivers could either directly fill
537 * &media_entity->@num_pads with 0 and &media_entity->@pads with NULL or call
538 * this function that will do the same.
540 * As the number of pads is known in advance, the pads array is not allocated
541 * dynamically but is managed by the entity driver. Most drivers will embed the
542 * pads array in a driver-specific structure, avoiding dynamic allocation.
544 * Drivers must set the direction of every pad in the pads array before calling
545 * media_entity_pads_init(). The function will initialize the other pads fields.
547 int media_entity_pads_init(struct media_entity
*entity
, u16 num_pads
,
548 struct media_pad
*pads
);
551 * media_entity_cleanup() - free resources associated with an entity
553 * @entity: entity where the pads belong
555 * This function must be called during the cleanup phase after unregistering
556 * the entity (currently, it does nothing).
558 static inline void media_entity_cleanup(struct media_entity
*entity
) {};
561 * media_create_pad_link() - creates a link between two entities.
563 * @source: pointer to &media_entity of the source pad.
564 * @source_pad: number of the source pad in the pads array
565 * @sink: pointer to &media_entity of the sink pad.
566 * @sink_pad: number of the sink pad in the pads array.
567 * @flags: Link flags, as defined in include/uapi/linux/media.h.
569 * Valid values for flags:
570 * A %MEDIA_LNK_FL_ENABLED flag indicates that the link is enabled and can be
571 * used to transfer media data. When two or more links target a sink pad,
572 * only one of them can be enabled at a time.
574 * A %MEDIA_LNK_FL_IMMUTABLE flag indicates that the link enabled state can't
575 * be modified at runtime. If %MEDIA_LNK_FL_IMMUTABLE is set, then
576 * %MEDIA_LNK_FL_ENABLED must also be set since an immutable link is
581 * Before calling this function, media_entity_pads_init() and
582 * media_device_register_entity() should be called previously for both ends.
584 __must_check
int media_create_pad_link(struct media_entity
*source
,
585 u16 source_pad
, struct media_entity
*sink
,
586 u16 sink_pad
, u32 flags
);
587 void __media_entity_remove_links(struct media_entity
*entity
);
590 * media_entity_remove_links() - remove all links associated with an entity
592 * @entity: pointer to &media_entity
594 * Note: this is called automatically when an entity is unregistered via
595 * media_device_register_entity().
597 void media_entity_remove_links(struct media_entity
*entity
);
600 * __media_entity_setup_link - Configure a media link without locking
601 * @link: The link being configured
602 * @flags: Link configuration flags
604 * The bulk of link setup is handled by the two entities connected through the
605 * link. This function notifies both entities of the link configuration change.
607 * If the link is immutable or if the current and new configuration are
608 * identical, return immediately.
610 * The user is expected to hold link->source->parent->mutex. If not,
611 * media_entity_setup_link() should be used instead.
613 int __media_entity_setup_link(struct media_link
*link
, u32 flags
);
616 * media_entity_setup_link() - changes the link flags properties in runtime
618 * @link: pointer to &media_link
619 * @flags: the requested new link flags
621 * The only configurable property is the %MEDIA_LNK_FL_ENABLED link flag
622 * flag to enable/disable a link. Links marked with the
623 * %MEDIA_LNK_FL_IMMUTABLE link flag can not be enabled or disabled.
625 * When a link is enabled or disabled, the media framework calls the
626 * link_setup operation for the two entities at the source and sink of the
627 * link, in that order. If the second link_setup call fails, another
628 * link_setup call is made on the first entity to restore the original link
631 * Media device drivers can be notified of link setup operations by setting the
632 * media_device::link_notify pointer to a callback function. If provided, the
633 * notification callback will be called before enabling and after disabling
636 * Entity drivers must implement the link_setup operation if any of their links
637 * is non-immutable. The operation must either configure the hardware or store
638 * the configuration information to be applied later.
640 * Link configuration must not have any side effect on other links. If an
641 * enabled link at a sink pad prevents another link at the same pad from
642 * being enabled, the link_setup operation must return -EBUSY and can't
643 * implicitly disable the first enabled link.
645 * NOTE: the valid values of the flags for the link is the same as described
646 * on media_create_pad_link(), for pad to pad links or the same as described
647 * on media_create_intf_link(), for interface to entity links.
649 int media_entity_setup_link(struct media_link
*link
, u32 flags
);
652 * media_entity_find_link - Find a link between two pads
653 * @source: Source pad
656 * Return a pointer to the link between the two entities. If no such link
657 * exists, return NULL.
659 struct media_link
*media_entity_find_link(struct media_pad
*source
,
660 struct media_pad
*sink
);
663 * media_entity_remote_pad - Find the pad at the remote end of a link
664 * @pad: Pad at the local end of the link
666 * Search for a remote pad connected to the given pad by iterating over all
667 * links originating or terminating at that pad until an enabled link is found.
669 * Return a pointer to the pad at the remote end of the first found enabled
670 * link, or NULL if no enabled link has been found.
672 struct media_pad
*media_entity_remote_pad(struct media_pad
*pad
);
675 * media_entity_get - Get a reference to the parent module
677 * @entity: The entity
679 * Get a reference to the parent media device module.
681 * The function will return immediately if @entity is NULL.
683 * Return a pointer to the entity on success or NULL on failure.
685 struct media_entity
*media_entity_get(struct media_entity
*entity
);
688 * media_entity_put - Release the reference to the parent module
690 * @entity: The entity
692 * Release the reference count acquired by media_entity_get().
694 * The function will return immediately if @entity is NULL.
696 void media_entity_put(struct media_entity
*entity
);
699 * media_entity_graph_walk_start - Start walking the media graph at a given entity
700 * @graph: Media graph structure that will be used to walk the graph
701 * @entity: Starting entity
703 * This function initializes the graph traversal structure to walk the entities
704 * graph starting at the given entity. The traversal structure must not be
705 * modified by the caller during graph traversal. When done the structure can
708 void media_entity_graph_walk_start(struct media_entity_graph
*graph
,
709 struct media_entity
*entity
);
712 * media_entity_graph_walk_next - Get the next entity in the graph
713 * @graph: Media graph structure
715 * Perform a depth-first traversal of the given media entities graph.
717 * The graph structure must have been previously initialized with a call to
718 * media_entity_graph_walk_start().
720 * Return the next entity in the graph or NULL if the whole graph have been
723 struct media_entity
*
724 media_entity_graph_walk_next(struct media_entity_graph
*graph
);
727 * media_entity_pipeline_start - Mark a pipeline as streaming
728 * @entity: Starting entity
729 * @pipe: Media pipeline to be assigned to all entities in the pipeline.
731 * Mark all entities connected to a given entity through enabled links, either
732 * directly or indirectly, as streaming. The given pipeline object is assigned to
733 * every entity in the pipeline and stored in the media_entity pipe field.
735 * Calls to this function can be nested, in which case the same number of
736 * media_entity_pipeline_stop() calls will be required to stop streaming. The
737 * pipeline pointer must be identical for all nested calls to
738 * media_entity_pipeline_start().
740 __must_check
int media_entity_pipeline_start(struct media_entity
*entity
,
741 struct media_pipeline
*pipe
);
744 * media_entity_pipeline_stop - Mark a pipeline as not streaming
745 * @entity: Starting entity
747 * Mark all entities connected to a given entity through enabled links, either
748 * directly or indirectly, as not streaming. The media_entity pipe field is
751 * If multiple calls to media_entity_pipeline_start() have been made, the same
752 * number of calls to this function are required to mark the pipeline as not
755 void media_entity_pipeline_stop(struct media_entity
*entity
);
758 * media_devnode_create() - creates and initializes a device node interface
760 * @mdev: pointer to struct &media_device
761 * @type: type of the interface, as given by MEDIA_INTF_T_* macros
762 * as defined in the uapi/media/media.h header.
763 * @flags: Interface flags as defined in uapi/media/media.h.
764 * @major: Device node major number.
765 * @minor: Device node minor number.
767 * Return: if succeeded, returns a pointer to the newly allocated
768 * &media_intf_devnode pointer.
770 struct media_intf_devnode
*
771 __must_check
media_devnode_create(struct media_device
*mdev
,
773 u32 major
, u32 minor
);
775 * media_devnode_remove() - removes a device node interface
777 * @devnode: pointer to &media_intf_devnode to be freed.
779 * When a device node interface is removed, all links to it are automatically
782 void media_devnode_remove(struct media_intf_devnode
*devnode
);
786 * media_create_intf_link() - creates a link between an entity and an interface
788 * @entity: pointer to %media_entity
789 * @intf: pointer to %media_interface
790 * @flags: Link flags, as defined in include/uapi/linux/media.h.
793 * Valid values for flags:
794 * The %MEDIA_LNK_FL_ENABLED flag indicates that the interface is connected to
795 * the entity hardware. That's the default value for interfaces. An
796 * interface may be disabled if the hardware is busy due to the usage
797 * of some other interface that it is currently controlling the hardware.
798 * A typical example is an hybrid TV device that handle only one type of
799 * stream on a given time. So, when the digital TV is streaming,
800 * the V4L2 interfaces won't be enabled, as such device is not able to
801 * also stream analog TV or radio.
805 * Before calling this function, media_devnode_create() should be called for
806 * the interface and media_device_register_entity() should be called for the
807 * interface that will be part of the link.
809 __must_check
media_create_intf_link(struct media_entity
*entity
,
810 struct media_interface
*intf
,
813 * __media_remove_intf_link() - remove a single interface link
815 * @link: pointer to &media_link.
817 * Note: this is an unlocked version of media_remove_intf_link()
819 void __media_remove_intf_link(struct media_link
*link
);
822 * media_remove_intf_link() - remove a single interface link
824 * @link: pointer to &media_link.
826 * Note: prefer to use this one, instead of __media_remove_intf_link()
828 void media_remove_intf_link(struct media_link
*link
);
831 * __media_remove_intf_links() - remove all links associated with an interface
833 * @intf: pointer to &media_interface
835 * Note: this is an unlocked version of media_remove_intf_links().
837 void __media_remove_intf_links(struct media_interface
*intf
);
839 * media_remove_intf_links() - remove all links associated with an interface
841 * @intf: pointer to &media_interface
845 * this is called automatically when an entity is unregistered via
846 * media_device_register_entity() and by media_devnode_remove().
848 * Prefer to use this one, instead of __media_remove_intf_links().
850 void media_remove_intf_links(struct media_interface
*intf
);
853 #define media_entity_call(entity, operation, args...) \
854 (((entity)->ops && (entity)->ops->operation) ? \
855 (entity)->ops->operation((entity) , ##args) : -ENOIOCTLCMD)