Add new interfaces to register and unregister entity_notify hook to media device to allow drivers to take appropriate actions when as new entities get added to the shared media device.When a new entity is registered, all registered entity_notify hooks are invoked to allow drivers or modules that registered hook to take appropriate action. For example, ALSA driver registers an entity_notify hook to parse the list of registered entities to determine if decoder has been linked to ALSA entity. au0828 bridge driver registers an entity_notify hook to create media graph for the device.
Signed-off-by: Shuah Khan shuahkh@osg.samsung.com --- drivers/media/media-device.c | 61 ++++++++++++++++++++++++++++++++++++++++++++ include/media/media-device.h | 25 ++++++++++++++++++ 2 files changed, 86 insertions(+)
diff --git a/drivers/media/media-device.c b/drivers/media/media-device.c index b786b10..20c85a9 100644 --- a/drivers/media/media-device.c +++ b/drivers/media/media-device.c @@ -536,6 +536,7 @@ static void media_device_release(struct media_devnode *mdev) int __must_check media_device_register_entity(struct media_device *mdev, struct media_entity *entity) { + struct media_entity_notify *notify, *next; unsigned int i; int ret;
@@ -575,6 +576,11 @@ int __must_check media_device_register_entity(struct media_device *mdev, media_gobj_create(mdev, MEDIA_GRAPH_PAD, &entity->pads[i].graph_obj);
+ /* invoke entity_notify callbacks */ + list_for_each_entry_safe(notify, next, &mdev->entity_notify, list) { + (notify)->notify(entity, notify->notify_data); + } + spin_unlock(&mdev->lock);
return 0; @@ -608,6 +614,8 @@ static void __media_device_unregister_entity(struct media_entity *entity) /* Remove the entity */ media_gobj_destroy(&entity->graph_obj);
+ /* invoke entity_notify callbacks to handle entity removal?? */ + entity->graph_obj.mdev = NULL; }
@@ -633,6 +641,7 @@ int __must_check media_device_init(struct media_device *mdev) INIT_LIST_HEAD(&mdev->interfaces); INIT_LIST_HEAD(&mdev->pads); INIT_LIST_HEAD(&mdev->links); + INIT_LIST_HEAD(&mdev->entity_notify); spin_lock_init(&mdev->lock); mutex_init(&mdev->graph_mutex); ida_init(&mdev->entity_internal_idx); @@ -680,11 +689,59 @@ int __must_check __media_device_register(struct media_device *mdev, } EXPORT_SYMBOL_GPL(__media_device_register);
+/** + * media_device_register_entity_notify - Register a media entity notify + * callback with a media device. When a new entity is registered, all + * the registered media_entity_notify callbacks are invoked. + * @mdev: The media device + * @nptr: The media_entity_notify + */ +int __must_check media_device_register_entity_notify(struct media_device *mdev, + struct media_entity_notify *nptr) +{ + spin_lock(&mdev->lock); + list_add_tail(&nptr->list, &mdev->entity_notify); + spin_unlock(&mdev->lock); + return 0; +} +EXPORT_SYMBOL_GPL(media_device_register_entity_notify); + +/** + * __media_device_unregister_entity_notify - Unregister a media entity notify + * callback with a media device. When a new entity is registered, all + * the registered media_entity_notify callbacks are invoked. + * @mdev: The media device + * @nptr: The media_entity_notify + * Non-locking version. Should be called with mdev->lock held. + */ +static void __media_device_unregister_entity_notify(struct media_device *mdev, + struct media_entity_notify *nptr) +{ + list_del(&nptr->list); +} + +/** + * media_device_unregister_entity_notify - Unregister a media entity notify + * callback with a media device. When a new entity is registered, all + * the registered media_entity_notify callbacks are invoked. + * @mdev: The media device + * @nptr: The media_entity_notify + */ +void media_device_unregister_entity_notify(struct media_device *mdev, + struct media_entity_notify *nptr) +{ + spin_lock(&mdev->lock); + __media_device_unregister_entity_notify(mdev, nptr); + spin_unlock(&mdev->lock); +} +EXPORT_SYMBOL_GPL(media_device_unregister_entity_notify); + void media_device_unregister(struct media_device *mdev) { struct media_entity *entity; struct media_entity *next; struct media_interface *intf, *tmp_intf; + struct media_entity_notify *notify, *nextp;
if (mdev == NULL) return; @@ -701,6 +758,10 @@ void media_device_unregister(struct media_device *mdev) list_for_each_entry_safe(entity, next, &mdev->entities, graph_obj.list) __media_device_unregister_entity(entity);
+ /* Remove all entity_notify callbacks from the media device */ + list_for_each_entry_safe(notify, nextp, &mdev->entity_notify, list) + __media_device_unregister_entity_notify(mdev, notify); + /* Remove all interfaces from the media device */ list_for_each_entry_safe(intf, tmp_intf, &mdev->interfaces, graph_obj.list) { diff --git a/include/media/media-device.h b/include/media/media-device.h index 122963a..6520d1c 100644 --- a/include/media/media-device.h +++ b/include/media/media-device.h @@ -264,6 +264,12 @@ struct ida; struct device;
+struct media_entity_notify { + struct list_head list; + void *notify_data; + void (*notify)(struct media_entity *entity, void *notify_data); +}; + /** * struct media_device - Media device * @dev: Parent device @@ -319,6 +325,9 @@ struct media_device { struct list_head pads; struct list_head links;
+ /* notify callback list invoked when a new entity is registered */ + struct list_head entity_notify; + /* Protects the graph objects creation/removal */ spinlock_t lock; /* Serializes graph operations. */ @@ -497,6 +506,11 @@ int __must_check media_device_register_entity(struct media_device *mdev, */ void media_device_unregister_entity(struct media_entity *entity);
+int __must_check media_device_register_entity_notify(struct media_device *mdev, + struct media_entity_notify *nptr); +void media_device_unregister_entity_notify(struct media_device *mdev, + struct media_entity_notify *nptr); + /** * media_device_get_devres() - get media device as device resource * creates if one doesn't exist @@ -552,6 +566,17 @@ static inline int media_device_register_entity(struct media_device *mdev, static inline void media_device_unregister_entity(struct media_entity *entity) { } +static inline int media_device_register_entity_notify( + struct media_device *mdev, + struct media_entity_notify *nptr) +{ + return 0; +} +static inline void media_device_unregister_entity_notify( + struct media_device *mdev, + struct media_entity_notify *nptr) +{ +} static inline struct media_device *media_device_get_devres(struct device *dev) { return NULL;