/* SPDX-License-Identifier: GPL-2.0-only */ /* * Media entity * * Copyright (C) 2010 Nokia Corporation * * Contacts: Laurent Pinchart <[email protected]> * Sakari Ailus <[email protected]> */ #ifndef _MEDIA_ENTITY_H #define _MEDIA_ENTITY_H #include <linux/bitmap.h> #include <linux/bug.h> #include <linux/container_of.h> #include <linux/fwnode.h> #include <linux/list.h> #include <linux/media.h> #include <linux/minmax.h> #include <linux/types.h> /* Enums used internally at the media controller to represent graphs */ /** * enum media_gobj_type - type of a graph object * * @MEDIA_GRAPH_ENTITY: Identify a media entity * @MEDIA_GRAPH_PAD: Identify a media pad * @MEDIA_GRAPH_LINK: Identify a media link * @MEDIA_GRAPH_INTF_DEVNODE: Identify a media Kernel API interface via * a device node */ enum media_gobj_type { … }; #define MEDIA_BITS_PER_TYPE … #define MEDIA_BITS_PER_ID … #define MEDIA_ID_MASK … /* Structs to represent the objects that belong to a media graph */ /** * struct media_gobj - Define a graph object. * * @mdev: Pointer to the struct &media_device that owns the object * @id: Non-zero object ID identifier. The ID should be unique * inside a media_device, as it is composed by * %MEDIA_BITS_PER_TYPE to store the type plus * %MEDIA_BITS_PER_ID to store the ID * @list: List entry stored in one of the per-type mdev object lists * * All objects on the media graph should have this struct embedded */ struct media_gobj { … }; #define MEDIA_ENTITY_ENUM_MAX_DEPTH … /** * struct media_entity_enum - An enumeration of media entities. * * @bmap: Bit map in which each bit represents one entity at struct * media_entity->internal_idx. * @idx_max: Number of bits in bmap */ struct media_entity_enum { … }; /** * struct media_graph - Media graph traversal state * * @stack: Graph traversal stack; the stack contains information * on the path the media entities to be walked and the * links through which they were reached. * @stack.entity: pointer to &struct media_entity at the graph. * @stack.link: pointer to &struct list_head. * @ent_enum: Visited entities * @top: The top of the stack */ struct media_graph { … }; /** * struct media_pipeline - Media pipeline related information * * @allocated: Media pipeline allocated and freed by the framework * @mdev: The media device the pipeline is part of * @pads: List of media_pipeline_pad * @start_count: Media pipeline start - stop count */ struct media_pipeline { … }; /** * struct media_pipeline_pad - A pad part of a media pipeline * * @list: Entry in the media_pad pads list * @pipe: The media_pipeline that the pad is part of * @pad: The media pad * * This structure associate a pad with a media pipeline. Instances of * media_pipeline_pad are created by media_pipeline_start() when it builds the * pipeline, and stored in the &media_pad.pads list. media_pipeline_stop() * removes the entries from the list and deletes them. */ struct media_pipeline_pad { … }; /** * struct media_pipeline_pad_iter - Iterator for media_pipeline_for_each_pad * * @cursor: The current element */ struct media_pipeline_pad_iter { … }; /** * struct media_pipeline_entity_iter - Iterator for media_pipeline_for_each_entity * * @ent_enum: The entity enumeration tracker * @cursor: The current element */ struct media_pipeline_entity_iter { … }; /** * struct media_link - A link object part of a media graph. * * @graph_obj: Embedded structure containing the media object common data * @list: Linked list associated with an entity or an interface that * owns the link. * @gobj0: Part of a union. Used to get the pointer for the first * graph_object of the link. * @source: Part of a union. Used only if the first object (gobj0) is * a pad. In that case, it represents the source pad. * @intf: Part of a union. Used only if the first object (gobj0) is * an interface. * @gobj1: Part of a union. Used to get the pointer for the second * graph_object of the link. * @sink: Part of a union. Used only if the second object (gobj1) is * a pad. In that case, it represents the sink pad. * @entity: Part of a union. Used only if the second object (gobj1) is * an entity. * @reverse: Pointer to the link for the reverse direction of a pad to pad * link. * @flags: Link flags, as defined in uapi/media.h (MEDIA_LNK_FL_*) * @is_backlink: Indicate if the link is a backlink. */ struct media_link { … }; /** * enum media_pad_signal_type - type of the signal inside a media pad * * @PAD_SIGNAL_DEFAULT: * Default signal. Use this when all inputs or all outputs are * uniquely identified by the pad number. * @PAD_SIGNAL_ANALOG: * The pad contains an analog signal. It can be Radio Frequency, * Intermediate Frequency, a baseband signal or sub-carriers. * Tuner inputs, IF-PLL demodulators, composite and s-video signals * should use it. * @PAD_SIGNAL_DV: * Contains a digital video signal, with can be a bitstream of samples * taken from an analog TV video source. On such case, it usually * contains the VBI data on it. * @PAD_SIGNAL_AUDIO: * Contains an Intermediate Frequency analog signal from an audio * sub-carrier or an audio bitstream. IF signals are provided by tuners * and consumed by audio AM/FM decoders. Bitstream audio is provided by * an audio decoder. */ enum media_pad_signal_type { … }; /** * struct media_pad - A media pad graph object. * * @graph_obj: Embedded structure containing the media object common data * @entity: Entity this pad belongs to * @index: Pad index in the entity pads array, numbered from 0 to n * @num_links: Number of links connected to this pad * @sig_type: Type of the signal inside a media pad * @flags: Pad flags, as defined in * :ref:`include/uapi/linux/media.h <media_header>` * (seek for ``MEDIA_PAD_FL_*``) * @pipe: Pipeline this pad belongs to. Use media_entity_pipeline() to * access this field. */ struct media_pad { … }; /** * struct media_entity_operations - Media entity operations * @get_fwnode_pad: Return the pad number based on a fwnode endpoint or * a negative value on error. This operation can be used * to map a fwnode to a media pad number. Optional. * @link_setup: Notify the entity of link changes. The operation can * return an error, in which case link setup will be * cancelled. Optional. * @link_validate: Return whether a link is valid from the entity point of * view. The media_pipeline_start() function * validates all links by calling this operation. Optional. * @has_pad_interdep: Return whether two pads of the entity are * interdependent. If two pads are interdependent they are * part of the same pipeline and enabling one of the pads * means that the other pad will become "locked" and * doesn't allow configuration changes. pad0 and pad1 are * guaranteed to not both be sinks or sources. Never call * the .has_pad_interdep() operation directly, always use * media_entity_has_pad_interdep(). * Optional: If the operation isn't implemented all pads * will be considered as interdependent. * * .. note:: * * Those these callbacks are called with struct &media_device.graph_mutex * mutex held. */ struct media_entity_operations { … }; /** * enum media_entity_type - Media entity type * * @MEDIA_ENTITY_TYPE_BASE: * The entity isn't embedded in another subsystem structure. * @MEDIA_ENTITY_TYPE_VIDEO_DEVICE: * The entity is embedded in a struct video_device instance. * @MEDIA_ENTITY_TYPE_V4L2_SUBDEV: * The entity is embedded in a struct v4l2_subdev instance. * * Media entity objects are often not instantiated directly, but the media * entity structure is inherited by (through embedding) other subsystem-specific * structures. The media entity type identifies the type of the subclass * structure that implements a media entity instance. * * This allows runtime type identification of media entities and safe casting to * the correct object type. For instance, a media entity structure instance * embedded in a v4l2_subdev structure instance will have the type * %MEDIA_ENTITY_TYPE_V4L2_SUBDEV and can safely be cast to a &v4l2_subdev * structure using the container_of() macro. */ enum media_entity_type { … }; /** * struct media_entity - A media entity graph object. * * @graph_obj: Embedded structure containing the media object common data. * @name: Entity name. * @obj_type: Type of the object that implements the media_entity. * @function: Entity main function, as defined in * :ref:`include/uapi/linux/media.h <media_header>` * (seek for ``MEDIA_ENT_F_*``) * @flags: Entity flags, as defined in * :ref:`include/uapi/linux/media.h <media_header>` * (seek for ``MEDIA_ENT_FL_*``) * @num_pads: Number of sink and source pads. * @num_links: Total number of links, forward and back, enabled and disabled. * @num_backlinks: Number of backlinks * @internal_idx: An unique internal entity specific number. The numbers are * re-used if entities are unregistered or registered again. * @pads: Pads array with the size defined by @num_pads. * @links: List of data links. * @ops: Entity operations. * @use_count: Use count for the entity. * @info: Union with devnode information. Kept just for backward * compatibility. * @info.dev: Contains device major and minor info. * @info.dev.major: device node major, if the device is a devnode. * @info.dev.minor: device node minor, if the device is a devnode. * * .. note:: * * The @use_count reference count must never be negative, but is a signed * integer on purpose: a simple ``WARN_ON(<0)`` check can be used to detect * reference count bugs that would make it negative. */ struct media_entity { … }; /** * media_entity_for_each_pad - Iterate on all pads in an entity * @entity: The entity the pads belong to * @iter: The iterator pad * * Iterate on all pads in a media entity. */ #define media_entity_for_each_pad(entity, iter) … /** * struct media_interface - A media interface graph object. * * @graph_obj: embedded graph object * @links: List of links pointing to graph entities * @type: Type of the interface as defined in * :ref:`include/uapi/linux/media.h <media_header>` * (seek for ``MEDIA_INTF_T_*``) * @flags: Interface flags as defined in * :ref:`include/uapi/linux/media.h <media_header>` * (seek for ``MEDIA_INTF_FL_*``) * * .. note:: * * Currently, no flags for &media_interface is defined. */ struct media_interface { … }; /** * struct media_intf_devnode - A media interface via a device node. * * @intf: embedded interface object * @major: Major number of a device node * @minor: Minor number of a device node */ struct media_intf_devnode { … }; /** * media_entity_id() - return the media entity graph object id * * @entity: pointer to &media_entity */ static inline u32 media_entity_id(struct media_entity *entity) { … } /** * media_type() - return the media object type * * @gobj: Pointer to the struct &media_gobj graph object */ static inline enum media_gobj_type media_type(struct media_gobj *gobj) { … } /** * media_id() - return the media object ID * * @gobj: Pointer to the struct &media_gobj graph object */ static inline u32 media_id(struct media_gobj *gobj) { … } /** * media_gobj_gen_id() - encapsulates type and ID on at the object ID * * @type: object type as define at enum &media_gobj_type. * @local_id: next ID, from struct &media_device.id. */ static inline u32 media_gobj_gen_id(enum media_gobj_type type, u64 local_id) { … } /** * is_media_entity_v4l2_video_device() - Check if the entity is a video_device * @entity: pointer to entity * * Return: %true if the entity is an instance of a video_device object and can * safely be cast to a struct video_device using the container_of() macro, or * %false otherwise. */ static inline bool is_media_entity_v4l2_video_device(struct media_entity *entity) { … } /** * is_media_entity_v4l2_subdev() - Check if the entity is a v4l2_subdev * @entity: pointer to entity * * Return: %true if the entity is an instance of a &v4l2_subdev object and can * safely be cast to a struct &v4l2_subdev using the container_of() macro, or * %false otherwise. */ static inline bool is_media_entity_v4l2_subdev(struct media_entity *entity) { … } /** * media_entity_enum_init - Initialise an entity enumeration * * @ent_enum: Entity enumeration to be initialised * @mdev: The related media device * * Return: zero on success or a negative error code. */ __must_check int media_entity_enum_init(struct media_entity_enum *ent_enum, struct media_device *mdev); /** * media_entity_enum_cleanup - Release resources of an entity enumeration * * @ent_enum: Entity enumeration to be released */ void media_entity_enum_cleanup(struct media_entity_enum *ent_enum); /** * media_entity_enum_zero - Clear the entire enum * * @ent_enum: Entity enumeration to be cleared */ static inline void media_entity_enum_zero(struct media_entity_enum *ent_enum) { … } /** * media_entity_enum_set - Mark a single entity in the enum * * @ent_enum: Entity enumeration * @entity: Entity to be marked */ static inline void media_entity_enum_set(struct media_entity_enum *ent_enum, struct media_entity *entity) { … } /** * media_entity_enum_clear - Unmark a single entity in the enum * * @ent_enum: Entity enumeration * @entity: Entity to be unmarked */ static inline void media_entity_enum_clear(struct media_entity_enum *ent_enum, struct media_entity *entity) { … } /** * media_entity_enum_test - Test whether the entity is marked * * @ent_enum: Entity enumeration * @entity: Entity to be tested * * Returns %true if the entity was marked. */ static inline bool media_entity_enum_test(struct media_entity_enum *ent_enum, struct media_entity *entity) { … } /** * media_entity_enum_test_and_set - Test whether the entity is marked, * and mark it * * @ent_enum: Entity enumeration * @entity: Entity to be tested * * Returns %true if the entity was marked, and mark it before doing so. */ static inline bool media_entity_enum_test_and_set(struct media_entity_enum *ent_enum, struct media_entity *entity) { … } /** * media_entity_enum_empty - Test whether the entire enum is empty * * @ent_enum: Entity enumeration * * Return: %true if the entity was empty. */ static inline bool media_entity_enum_empty(struct media_entity_enum *ent_enum) { … } /** * media_entity_enum_intersects - Test whether two enums intersect * * @ent_enum1: First entity enumeration * @ent_enum2: Second entity enumeration * * Return: %true if entity enumerations @ent_enum1 and @ent_enum2 intersect, * otherwise %false. */ static inline bool media_entity_enum_intersects( struct media_entity_enum *ent_enum1, struct media_entity_enum *ent_enum2) { … } /** * gobj_to_entity - returns the struct &media_entity pointer from the * @gobj contained on it. * * @gobj: Pointer to the struct &media_gobj graph object */ #define gobj_to_entity(gobj) … /** * gobj_to_pad - returns the struct &media_pad pointer from the * @gobj contained on it. * * @gobj: Pointer to the struct &media_gobj graph object */ #define gobj_to_pad(gobj) … /** * gobj_to_link - returns the struct &media_link pointer from the * @gobj contained on it. * * @gobj: Pointer to the struct &media_gobj graph object */ #define gobj_to_link(gobj) … /** * gobj_to_intf - returns the struct &media_interface pointer from the * @gobj contained on it. * * @gobj: Pointer to the struct &media_gobj graph object */ #define gobj_to_intf(gobj) … /** * intf_to_devnode - returns the struct media_intf_devnode pointer from the * @intf contained on it. * * @intf: Pointer to struct &media_intf_devnode */ #define intf_to_devnode(intf) … /** * media_gobj_create - Initialize a graph object * * @mdev: Pointer to the &media_device that contains the object * @type: Type of the object * @gobj: Pointer to the struct &media_gobj graph object * * This routine initializes the embedded struct &media_gobj inside a * media graph object. It is called automatically if ``media_*_create`` * function calls are used. However, if the object (entity, link, pad, * interface) is embedded on some other object, this function should be * called before registering the object at the media controller. */ void media_gobj_create(struct media_device *mdev, enum media_gobj_type type, struct media_gobj *gobj); /** * media_gobj_destroy - Stop using a graph object on a media device * * @gobj: Pointer to the struct &media_gobj graph object * * This should be called by all routines like media_device_unregister() * that remove/destroy media graph objects. */ void media_gobj_destroy(struct media_gobj *gobj); /** * media_entity_pads_init() - Initialize the entity pads * * @entity: entity where the pads belong * @num_pads: total number of sink and source pads * @pads: Array of @num_pads pads. * * The pads array is managed by the entity driver and passed to * media_entity_pads_init() where its pointer will be stored in the * &media_entity structure. * * If no pads are needed, drivers could either directly fill * &media_entity->num_pads with 0 and &media_entity->pads with %NULL or call * this function that will do the same. * * As the number of pads is known in advance, the pads array is not allocated * dynamically but is managed by the entity driver. Most drivers will embed the * pads array in a driver-specific structure, avoiding dynamic allocation. * * Drivers must set the direction of every pad in the pads array before calling * media_entity_pads_init(). The function will initialize the other pads fields. */ int media_entity_pads_init(struct media_entity *entity, u16 num_pads, struct media_pad *pads); /** * media_entity_cleanup() - free resources associated with an entity * * @entity: entity where the pads belong * * This function must be called during the cleanup phase after unregistering * the entity (currently, it does nothing). * * Calling media_entity_cleanup() on a media_entity whose memory has been * zeroed but that has not been initialized with media_entity_pad_init() is * valid and is a no-op. */ #if IS_ENABLED(CONFIG_MEDIA_CONTROLLER) static inline void media_entity_cleanup(struct media_entity *entity) { … } #else #define media_entity_cleanup … #endif /** * media_get_pad_index() - retrieves a pad index from an entity * * @entity: entity where the pads belong * @pad_type: the type of the pad, one of MEDIA_PAD_FL_* pad types * @sig_type: type of signal of the pad to be search * * This helper function finds the first pad index inside an entity that * satisfies both @is_sink and @sig_type conditions. * * Return: * * On success, return the pad number. If the pad was not found or the media * entity is a NULL pointer, return -EINVAL. */ int media_get_pad_index(struct media_entity *entity, u32 pad_type, enum media_pad_signal_type sig_type); /** * media_create_pad_link() - creates a link between two entities. * * @source: pointer to &media_entity of the source pad. * @source_pad: number of the source pad in the pads array * @sink: pointer to &media_entity of the sink pad. * @sink_pad: number of the sink pad in the pads array. * @flags: Link flags, as defined in * :ref:`include/uapi/linux/media.h <media_header>` * ( seek for ``MEDIA_LNK_FL_*``) * * Valid values for flags: * * %MEDIA_LNK_FL_ENABLED * Indicates that the link is enabled and can be used to transfer media data. * When two or more links target a sink pad, only one of them can be * enabled at a time. * * %MEDIA_LNK_FL_IMMUTABLE * Indicates that the link enabled state can't be modified at runtime. If * %MEDIA_LNK_FL_IMMUTABLE is set, then %MEDIA_LNK_FL_ENABLED must also be * set, since an immutable link is always enabled. * * .. note:: * * Before calling this function, media_entity_pads_init() and * media_device_register_entity() should be called previously for both ends. */ __must_check int media_create_pad_link(struct media_entity *source, u16 source_pad, struct media_entity *sink, u16 sink_pad, u32 flags); /** * media_create_pad_links() - creates a link between two entities. * * @mdev: Pointer to the media_device that contains the object * @source_function: Function of the source entities. Used only if @source is * NULL. * @source: pointer to &media_entity of the source pad. If NULL, it will use * all entities that matches the @sink_function. * @source_pad: number of the source pad in the pads array * @sink_function: Function of the sink entities. Used only if @sink is NULL. * @sink: pointer to &media_entity of the sink pad. If NULL, it will use * all entities that matches the @sink_function. * @sink_pad: number of the sink pad in the pads array. * @flags: Link flags, as defined in include/uapi/linux/media.h. * @allow_both_undefined: if %true, then both @source and @sink can be NULL. * In such case, it will create a crossbar between all entities that * matches @source_function to all entities that matches @sink_function. * If %false, it will return 0 and won't create any link if both @source * and @sink are NULL. * * Valid values for flags: * * A %MEDIA_LNK_FL_ENABLED flag indicates that the link is enabled and can be * used to transfer media data. If multiple links are created and this * flag is passed as an argument, only the first created link will have * this flag. * * A %MEDIA_LNK_FL_IMMUTABLE flag indicates that the link enabled state can't * be modified at runtime. If %MEDIA_LNK_FL_IMMUTABLE is set, then * %MEDIA_LNK_FL_ENABLED must also be set since an immutable link is * always enabled. * * It is common for some devices to have multiple source and/or sink entities * of the same type that should be linked. While media_create_pad_link() * creates link by link, this function is meant to allow 1:n, n:1 and even * cross-bar (n:n) links. * * .. note:: * * Before calling this function, media_entity_pads_init() and * media_device_register_entity() should be called previously for the * entities to be linked. */ int media_create_pad_links(const struct media_device *mdev, const u32 source_function, struct media_entity *source, const u16 source_pad, const u32 sink_function, struct media_entity *sink, const u16 sink_pad, u32 flags, const bool allow_both_undefined); void __media_entity_remove_links(struct media_entity *entity); /** * media_entity_remove_links() - remove all links associated with an entity * * @entity: pointer to &media_entity * * .. note:: * * This is called automatically when an entity is unregistered via * media_device_register_entity(). */ void media_entity_remove_links(struct media_entity *entity); /** * __media_entity_setup_link - Configure a media link without locking * @link: The link being configured * @flags: Link configuration flags * * The bulk of link setup is handled by the two entities connected through the * link. This function notifies both entities of the link configuration change. * * If the link is immutable or if the current and new configuration are * identical, return immediately. * * The user is expected to hold link->source->parent->mutex. If not, * media_entity_setup_link() should be used instead. */ int __media_entity_setup_link(struct media_link *link, u32 flags); /** * media_entity_setup_link() - changes the link flags properties in runtime * * @link: pointer to &media_link * @flags: the requested new link flags * * The only configurable property is the %MEDIA_LNK_FL_ENABLED link flag * to enable/disable a link. Links marked with the * %MEDIA_LNK_FL_IMMUTABLE link flag can not be enabled or disabled. * * When a link is enabled or disabled, the media framework calls the * link_setup operation for the two entities at the source and sink of the * link, in that order. If the second link_setup call fails, another * link_setup call is made on the first entity to restore the original link * flags. * * Media device drivers can be notified of link setup operations by setting the * &media_device.link_notify pointer to a callback function. If provided, the * notification callback will be called before enabling and after disabling * links. * * Entity drivers must implement the link_setup operation if any of their links * is non-immutable. The operation must either configure the hardware or store * the configuration information to be applied later. * * Link configuration must not have any side effect on other links. If an * enabled link at a sink pad prevents another link at the same pad from * being enabled, the link_setup operation must return %-EBUSY and can't * implicitly disable the first enabled link. * * .. note:: * * The valid values of the flags for the link is the same as described * on media_create_pad_link(), for pad to pad links or the same as described * on media_create_intf_link(), for interface to entity links. */ int media_entity_setup_link(struct media_link *link, u32 flags); /** * media_entity_find_link - Find a link between two pads * @source: Source pad * @sink: Sink pad * * Return: returns a pointer to the link between the two entities. If no * such link exists, return %NULL. */ struct media_link *media_entity_find_link(struct media_pad *source, struct media_pad *sink); /** * media_pad_remote_pad_first - Find the first pad at the remote end of a link * @pad: Pad at the local end of the link * * Search for a remote pad connected to the given pad by iterating over all * links originating or terminating at that pad until an enabled link is found. * * Return: returns a pointer to the pad at the remote end of the first found * enabled link, or %NULL if no enabled link has been found. */ struct media_pad *media_pad_remote_pad_first(const struct media_pad *pad); /** * media_pad_remote_pad_unique - Find a remote pad connected to a pad * @pad: The pad * * Search for and return a remote pad connected to @pad through an enabled * link. If multiple (or no) remote pads are found, an error is returned. * * The uniqueness constraint makes this helper function suitable for entities * that support a single active source at a time on a given pad. * * Return: A pointer to the remote pad, or one of the following error pointers * if an error occurs: * * * -ENOTUNIQ - Multiple links are enabled * * -ENOLINK - No connected pad found */ struct media_pad *media_pad_remote_pad_unique(const struct media_pad *pad); /** * media_entity_remote_pad_unique - Find a remote pad connected to an entity * @entity: The entity * @type: The type of pad to find (MEDIA_PAD_FL_SINK or MEDIA_PAD_FL_SOURCE) * * Search for and return a remote pad of @type connected to @entity through an * enabled link. If multiple (or no) remote pads match these criteria, an error * is returned. * * The uniqueness constraint makes this helper function suitable for entities * that support a single active source or sink at a time. * * Return: A pointer to the remote pad, or one of the following error pointers * if an error occurs: * * * -ENOTUNIQ - Multiple links are enabled * * -ENOLINK - No connected pad found */ struct media_pad * media_entity_remote_pad_unique(const struct media_entity *entity, unsigned int type); /** * media_entity_remote_source_pad_unique - Find a remote source pad connected to * an entity * @entity: The entity * * Search for and return a remote source pad connected to @entity through an * enabled link. If multiple (or no) remote pads match these criteria, an error * is returned. * * The uniqueness constraint makes this helper function suitable for entities * that support a single active source at a time. * * Return: A pointer to the remote pad, or one of the following error pointers * if an error occurs: * * * -ENOTUNIQ - Multiple links are enabled * * -ENOLINK - No connected pad found */ static inline struct media_pad * media_entity_remote_source_pad_unique(const struct media_entity *entity) { … } /** * media_pad_is_streaming - Test if a pad is part of a streaming pipeline * @pad: The pad * * Return: True if the pad is part of a pipeline started with the * media_pipeline_start() function, false otherwise. */ static inline bool media_pad_is_streaming(const struct media_pad *pad) { … } /** * media_entity_is_streaming - Test if an entity is part of a streaming pipeline * @entity: The entity * * Return: True if the entity is part of a pipeline started with the * media_pipeline_start() function, false otherwise. */ static inline bool media_entity_is_streaming(const struct media_entity *entity) { … } /** * media_entity_pipeline - Get the media pipeline an entity is part of * @entity: The entity * * DEPRECATED: use media_pad_pipeline() instead. * * This function returns the media pipeline that an entity has been associated * with when constructing the pipeline with media_pipeline_start(). The pointer * remains valid until media_pipeline_stop() is called. * * In general, entities can be part of multiple pipelines, when carrying * multiple streams (either on different pads, or on the same pad using * multiplexed streams). This function is to be used only for entities that * do not support multiple pipelines. * * Return: The media_pipeline the entity is part of, or NULL if the entity is * not part of any pipeline. */ struct media_pipeline *media_entity_pipeline(struct media_entity *entity); /** * media_pad_pipeline - Get the media pipeline a pad is part of * @pad: The pad * * This function returns the media pipeline that a pad has been associated * with when constructing the pipeline with media_pipeline_start(). The pointer * remains valid until media_pipeline_stop() is called. * * Return: The media_pipeline the pad is part of, or NULL if the pad is * not part of any pipeline. */ struct media_pipeline *media_pad_pipeline(struct media_pad *pad); /** * media_entity_get_fwnode_pad - Get pad number from fwnode * * @entity: The entity * @fwnode: Pointer to the fwnode_handle which should be used to find the pad * @direction_flags: Expected direction of the pad, as defined in * :ref:`include/uapi/linux/media.h <media_header>` * (seek for ``MEDIA_PAD_FL_*``) * * This function can be used to resolve the media pad number from * a fwnode. This is useful for devices which use more complex * mappings of media pads. * * If the entity does not implement the get_fwnode_pad() operation * then this function searches the entity for the first pad that * matches the @direction_flags. * * Return: returns the pad number on success or a negative error code. */ int media_entity_get_fwnode_pad(struct media_entity *entity, const struct fwnode_handle *fwnode, unsigned long direction_flags); /** * media_graph_walk_init - Allocate resources used by graph walk. * * @graph: Media graph structure that will be used to walk the graph * @mdev: Pointer to the &media_device that contains the object * * This function is deprecated, use media_pipeline_for_each_pad() instead. * * The caller is required to hold the media_device graph_mutex during the graph * walk until the graph state is released. * * Returns zero on success or a negative error code otherwise. */ __must_check int media_graph_walk_init( struct media_graph *graph, struct media_device *mdev); /** * media_graph_walk_cleanup - Release resources used by graph walk. * * @graph: Media graph structure that will be used to walk the graph * * This function is deprecated, use media_pipeline_for_each_pad() instead. */ void media_graph_walk_cleanup(struct media_graph *graph); /** * media_graph_walk_start - Start walking the media graph at a * given entity * * @graph: Media graph structure that will be used to walk the graph * @entity: Starting entity * * This function is deprecated, use media_pipeline_for_each_pad() instead. * * Before using this function, media_graph_walk_init() must be * used to allocate resources used for walking the graph. This * function initializes the graph traversal structure to walk the * entities graph starting at the given entity. The traversal * structure must not be modified by the caller during graph * traversal. After the graph walk, the resources must be released * using media_graph_walk_cleanup(). */ void media_graph_walk_start(struct media_graph *graph, struct media_entity *entity); /** * media_graph_walk_next - Get the next entity in the graph * @graph: Media graph structure * * This function is deprecated, use media_pipeline_for_each_pad() instead. * * Perform a depth-first traversal of the given media entities graph. * * The graph structure must have been previously initialized with a call to * media_graph_walk_start(). * * Return: returns the next entity in the graph or %NULL if the whole graph * have been traversed. */ struct media_entity *media_graph_walk_next(struct media_graph *graph); /** * media_pipeline_start - Mark a pipeline as streaming * @pad: Starting pad * @pipe: Media pipeline to be assigned to all pads in the pipeline. * * Mark all pads connected to a given pad through enabled links, either * directly or indirectly, as streaming. The given pipeline object is assigned * to every pad in the pipeline and stored in the media_pad pipe field. * * Calls to this function can be nested, in which case the same number of * media_pipeline_stop() calls will be required to stop streaming. The * pipeline pointer must be identical for all nested calls to * media_pipeline_start(). */ __must_check int media_pipeline_start(struct media_pad *pad, struct media_pipeline *pipe); /** * __media_pipeline_start - Mark a pipeline as streaming * * @pad: Starting pad * @pipe: Media pipeline to be assigned to all pads in the pipeline. * * ..note:: This is the non-locking version of media_pipeline_start() */ __must_check int __media_pipeline_start(struct media_pad *pad, struct media_pipeline *pipe); /** * media_pipeline_stop - Mark a pipeline as not streaming * @pad: Starting pad * * Mark all pads connected to a given pad through enabled links, either * directly or indirectly, as not streaming. The media_pad pipe field is * reset to %NULL. * * If multiple calls to media_pipeline_start() have been made, the same * number of calls to this function are required to mark the pipeline as not * streaming. */ void media_pipeline_stop(struct media_pad *pad); /** * __media_pipeline_stop - Mark a pipeline as not streaming * * @pad: Starting pad * * .. note:: This is the non-locking version of media_pipeline_stop() */ void __media_pipeline_stop(struct media_pad *pad); struct media_pad * __media_pipeline_pad_iter_next(struct media_pipeline *pipe, struct media_pipeline_pad_iter *iter, struct media_pad *pad); /** * media_pipeline_for_each_pad - Iterate on all pads in a media pipeline * @pipe: The pipeline * @iter: The iterator (struct media_pipeline_pad_iter) * @pad: The iterator pad * * Iterate on all pads in a media pipeline. This is only valid after the * pipeline has been built with media_pipeline_start() and before it gets * destroyed with media_pipeline_stop(). */ #define media_pipeline_for_each_pad(pipe, iter, pad) … /** * media_pipeline_entity_iter_init - Initialize a pipeline entity iterator * @pipe: The pipeline * @iter: The iterator * * This function must be called to initialize the iterator before using it in a * media_pipeline_for_each_entity() loop. The iterator must be destroyed by a * call to media_pipeline_entity_iter_cleanup after the loop (including in code * paths that break from the loop). * * The same iterator can be used in multiple consecutive loops without being * destroyed and reinitialized. * * Return: 0 on success or a negative error code otherwise. */ int media_pipeline_entity_iter_init(struct media_pipeline *pipe, struct media_pipeline_entity_iter *iter); /** * media_pipeline_entity_iter_cleanup - Destroy a pipeline entity iterator * @iter: The iterator * * This function must be called to destroy iterators initialized with * media_pipeline_entity_iter_init(). */ void media_pipeline_entity_iter_cleanup(struct media_pipeline_entity_iter *iter); struct media_entity * __media_pipeline_entity_iter_next(struct media_pipeline *pipe, struct media_pipeline_entity_iter *iter, struct media_entity *entity); /** * media_pipeline_for_each_entity - Iterate on all entities in a media pipeline * @pipe: The pipeline * @iter: The iterator (struct media_pipeline_entity_iter) * @entity: The iterator entity * * Iterate on all entities in a media pipeline. This is only valid after the * pipeline has been built with media_pipeline_start() and before it gets * destroyed with media_pipeline_stop(). The iterator must be initialized with * media_pipeline_entity_iter_init() before iteration, and destroyed with * media_pipeline_entity_iter_cleanup() after (including in code paths that * break from the loop). */ #define media_pipeline_for_each_entity(pipe, iter, entity) … /** * media_pipeline_alloc_start - Mark a pipeline as streaming * @pad: Starting pad * * media_pipeline_alloc_start() is similar to media_pipeline_start() but instead * of working on a given pipeline the function will use an existing pipeline if * the pad is already part of a pipeline, or allocate a new pipeline. * * Calls to media_pipeline_alloc_start() must be matched with * media_pipeline_stop(). */ __must_check int media_pipeline_alloc_start(struct media_pad *pad); /** * media_devnode_create() - creates and initializes a device node interface * * @mdev: pointer to struct &media_device * @type: type of the interface, as given by * :ref:`include/uapi/linux/media.h <media_header>` * ( seek for ``MEDIA_INTF_T_*``) macros. * @flags: Interface flags, as defined in * :ref:`include/uapi/linux/media.h <media_header>` * ( seek for ``MEDIA_INTF_FL_*``) * @major: Device node major number. * @minor: Device node minor number. * * Return: if succeeded, returns a pointer to the newly allocated * &media_intf_devnode pointer. * * .. note:: * * Currently, no flags for &media_interface is defined. */ struct media_intf_devnode * __must_check media_devnode_create(struct media_device *mdev, u32 type, u32 flags, u32 major, u32 minor); /** * media_devnode_remove() - removes a device node interface * * @devnode: pointer to &media_intf_devnode to be freed. * * When a device node interface is removed, all links to it are automatically * removed. */ void media_devnode_remove(struct media_intf_devnode *devnode); /** * media_create_intf_link() - creates a link between an entity and an interface * * @entity: pointer to %media_entity * @intf: pointer to %media_interface * @flags: Link flags, as defined in * :ref:`include/uapi/linux/media.h <media_header>` * ( seek for ``MEDIA_LNK_FL_*``) * * * Valid values for flags: * * %MEDIA_LNK_FL_ENABLED * Indicates that the interface is connected to the entity hardware. * That's the default value for interfaces. An interface may be disabled if * the hardware is busy due to the usage of some other interface that it is * currently controlling the hardware. * * A typical example is an hybrid TV device that handle only one type of * stream on a given time. So, when the digital TV is streaming, * the V4L2 interfaces won't be enabled, as such device is not able to * also stream analog TV or radio. * * .. note:: * * Before calling this function, media_devnode_create() should be called for * the interface and media_device_register_entity() should be called for the * interface that will be part of the link. */ struct media_link * __must_check media_create_intf_link(struct media_entity *entity, struct media_interface *intf, u32 flags); /** * __media_remove_intf_link() - remove a single interface link * * @link: pointer to &media_link. * * .. note:: This is an unlocked version of media_remove_intf_link() */ void __media_remove_intf_link(struct media_link *link); /** * media_remove_intf_link() - remove a single interface link * * @link: pointer to &media_link. * * .. note:: Prefer to use this one, instead of __media_remove_intf_link() */ void media_remove_intf_link(struct media_link *link); /** * __media_remove_intf_links() - remove all links associated with an interface * * @intf: pointer to &media_interface * * .. note:: This is an unlocked version of media_remove_intf_links(). */ void __media_remove_intf_links(struct media_interface *intf); /** * media_remove_intf_links() - remove all links associated with an interface * * @intf: pointer to &media_interface * * .. note:: * * #) This is called automatically when an entity is unregistered via * media_device_register_entity() and by media_devnode_remove(). * * #) Prefer to use this one, instead of __media_remove_intf_links(). */ void media_remove_intf_links(struct media_interface *intf); /** * media_entity_call - Calls a struct media_entity_operations operation on * an entity * * @entity: entity where the @operation will be called * @operation: type of the operation. Should be the name of a member of * struct &media_entity_operations. * * This helper function will check if @operation is not %NULL. On such case, * it will issue a call to @operation\(@entity, @args\). */ #define media_entity_call(entity, operation, args...) … /** * media_create_ancillary_link() - create an ancillary link between two * instances of &media_entity * * @primary: pointer to the primary &media_entity * @ancillary: pointer to the ancillary &media_entity * * Create an ancillary link between two entities, indicating that they * represent two connected pieces of hardware that form a single logical unit. * A typical example is a camera lens controller being linked to the sensor that * it is supporting. * * The function sets both MEDIA_LNK_FL_ENABLED and MEDIA_LNK_FL_IMMUTABLE for * the new link. */ struct media_link * media_create_ancillary_link(struct media_entity *primary, struct media_entity *ancillary); /** * __media_entity_next_link() - Iterate through a &media_entity's links * * @entity: pointer to the &media_entity * @link: pointer to a &media_link to hold the iterated values * @link_type: one of the MEDIA_LNK_FL_LINK_TYPE flags * * Return the next link against an entity matching a specific link type. This * allows iteration through an entity's links whilst guaranteeing all of the * returned links are of the given type. */ struct media_link *__media_entity_next_link(struct media_entity *entity, struct media_link *link, unsigned long link_type); /** * for_each_media_entity_data_link() - Iterate through an entity's data links * * @entity: pointer to the &media_entity * @link: pointer to a &media_link to hold the iterated values * * Iterate over a &media_entity's data links */ #define for_each_media_entity_data_link(entity, link) … #endif