From ab22e77cd3d3073c8cac51b59713ef635678dfbe Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Fri, 11 Dec 2015 07:44:40 -0200 Subject: [media] media framework: rename pads init function to media_entity_pads_init() With the MC next gen rework, what's left for media_entity_init() is to just initialize the PADs. However, certain devices, like a FLASH led/light doesn't have any input or output PAD. So, there's no reason why calling media_entity_init() would be mandatory. Also, despite its name, what this function actually does is to initialize the PADs data. So, rename it to media_entity_pads_init() in order to reflect that. The media entity actual init happens during entity register, at media_device_register_entity(). We should move init of num_links and num_backlinks to it. Signed-off-by: Mauro Carvalho Chehab --- Documentation/media-framework.txt | 18 +++++++++++------- Documentation/video4linux/v4l2-framework.txt | 8 ++++---- Documentation/zh_CN/video4linux/v4l2-framework.txt | 8 ++++---- 3 files changed, 19 insertions(+), 15 deletions(-) (limited to 'Documentation') diff --git a/Documentation/media-framework.txt b/Documentation/media-framework.txt index b424de6c3bb3..7fbfe4bd1f47 100644 --- a/Documentation/media-framework.txt +++ b/Documentation/media-framework.txt @@ -101,14 +101,18 @@ include/media/media-entity.h. The structure is usually embedded into a higher-level structure, such as a v4l2_subdev or video_device instance, although drivers can allocate entities directly. -Drivers initialize entities by calling +Drivers initialize entity pads by calling - media_entity_init(struct media_entity *entity, u16 num_pads, + media_entity_pads_init(struct media_entity *entity, u16 num_pads, struct media_pad *pads); -The media_entity name, type, flags, revision and group_id fields can be -initialized before or after calling media_entity_init. Entities embedded in -higher-level standard structures can have some of those fields set by the +If no pads are needed, drivers could directly fill entity->num_pads +with 0 and entity->pads with NULL or to call the above function that +will do the same. + +The media_entity name, type, flags, revision and group_id fields should be +initialized before calling media_device_register_entity(). Entities embedded +in higher-level standard structures can have some of those fields set by the higher-level framework. As the number of pads is known in advance, the pads array is not allocated @@ -116,10 +120,10 @@ 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_init. The function will initialize the other pads fields. +media_entity_pads_init. The function will initialize the other pads fields. Unlike the number of pads, the total number of links isn't always known in -advance by the entity driver. As an initial estimate, media_entity_init +advance by the entity driver. As an initial estimate, media_entity_pads_init pre-allocates a number of links equal to the number of pads. The links array will be reallocated if it grows beyond the initial estimate. diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 2e0fc28fa12f..fa41608ab2b4 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -295,12 +295,12 @@ module owner. This is done for you if you use the i2c helper functions. If integration with the media framework is needed, you must initialize the media_entity struct embedded in the v4l2_subdev struct (entity field) by -calling media_entity_init(): +calling media_entity_pads_init(), if the entity has pads: struct media_pad *pads = &my_sd->pads; int err; - err = media_entity_init(&sd->entity, npads, pads); + err = media_entity_pads_init(&sd->entity, npads, pads); The pads array must have been previously initialized. There is no need to manually set the struct media_entity function and name fields, but the @@ -695,12 +695,12 @@ difference is that the inode argument is omitted since it is never used. If integration with the media framework is needed, you must initialize the media_entity struct embedded in the video_device struct (entity field) by -calling media_entity_init(): +calling media_entity_pads_init(): struct media_pad *pad = &my_vdev->pad; int err; - err = media_entity_init(&vdev->entity, 1, pad); + err = media_entity_pads_init(&vdev->entity, 1, pad); The pads array must have been previously initialized. There is no need to manually set the struct media_entity type and name fields. diff --git a/Documentation/zh_CN/video4linux/v4l2-framework.txt b/Documentation/zh_CN/video4linux/v4l2-framework.txt index ff815cb92031..698660b7f21f 100644 --- a/Documentation/zh_CN/video4linux/v4l2-framework.txt +++ b/Documentation/zh_CN/video4linux/v4l2-framework.txt @@ -289,13 +289,13 @@ struct v4l2_subdev_ops { 然后，你必须用一个唯一的名字初始化 subdev->name，并初始化模块的 owner 域。若使用 i2c 辅助函数，这些都会帮你处理好。 -若需同媒体框架整合，你必须调用 media_entity_init() 初始化 v4l2_subdev +若需同媒体框架整合，你必须调用 media_entity_pads_init() 初始化 v4l2_subdev 结构体中的 media_entity 结构体（entity 域）： struct media_pad *pads = &my_sd->pads; int err; - err = media_entity_init(&sd->entity, npads, pads); + err = media_entity_pads_init(&sd->entity, npads, pads); pads 数组必须预先初始化。无须手动设置 media_entity 的 type 和 name 域，但如有必要，revision 域必须初始化。 @@ -596,13 +596,13 @@ void v4l2_disable_ioctl(struct video_device *vdev, unsigned int cmd); v4l2_file_operations 结构体是 file_operations 的一个子集。其主要 区别在于：因 inode 参数从未被使用，它将被忽略。 -如果需要与媒体框架整合，你必须通过调用 media_entity_init() 初始化 +如果需要与媒体框架整合，你必须通过调用 media_entity_pads_init() 初始化 嵌入在 video_device 结构体中的 media_entity（entity 域）结构体： struct media_pad *pad = &my_vdev->pad; int err; - err = media_entity_init(&vdev->entity, 1, pad); + err = media_entity_pads_init(&vdev->entity, 1, pad); pads 数组必须预先初始化。没有必要手动设置 media_entity 的 type 和 name 域。 -- cgit v1.2.1