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authorMauro Carvalho Chehab <mchehab@osg.samsung.com>2015-12-11 12:44:40 +0300
committerMauro Carvalho Chehab <mchehab@osg.samsung.com>2016-01-11 17:19:03 +0300
commitab22e77cd3d3073c8cac51b59713ef635678dfbe (patch)
treedfe14b163cd094531b260cab7e7d69d035b751da /Documentation
parentb83e250833e6c40a9e92935ea6fc125b64792357 (diff)
downloadlinux-ab22e77cd3d3073c8cac51b59713ef635678dfbe.tar.xz
[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 <mchehab@osg.samsung.com>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/media-framework.txt18
-rw-r--r--Documentation/video4linux/v4l2-framework.txt8
-rw-r--r--Documentation/zh_CN/video4linux/v4l2-framework.txt8
3 files changed, 19 insertions, 15 deletions
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。