diff options
| -rw-r--r-- | Documentation/video4linux/v4l2-framework.txt | 13 | ||||
| -rw-r--r-- | Documentation/zh_CN/video4linux/v4l2-framework.txt | 13 |
2 files changed, 12 insertions, 14 deletions
diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index a300b283a1a..24353ecab19 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -246,7 +246,6 @@ may be NULL if the subdev driver does not support anything from that category. It looks like this: struct v4l2_subdev_core_ops { - int (*g_chip_ident)(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip); int (*log_status)(struct v4l2_subdev *sd); int (*init)(struct v4l2_subdev *sd, u32 val); ... @@ -346,24 +345,24 @@ Afterwards the subdev module can be unloaded and sd->dev == NULL. You can call an ops function either directly: - err = sd->ops->core->g_chip_ident(sd, &chip); + err = sd->ops->core->g_std(sd, &norm); but it is better and easier to use this macro: - err = v4l2_subdev_call(sd, core, g_chip_ident, &chip); + err = v4l2_subdev_call(sd, core, g_std, &norm); The macro will to the right NULL pointer checks and returns -ENODEV if subdev -is NULL, -ENOIOCTLCMD if either subdev->core or subdev->core->g_chip_ident is -NULL, or the actual result of the subdev->ops->core->g_chip_ident ops. +is NULL, -ENOIOCTLCMD if either subdev->core or subdev->core->g_std is +NULL, or the actual result of the subdev->ops->core->g_std ops. It is also possible to call all or a subset of the sub-devices: - v4l2_device_call_all(v4l2_dev, 0, core, g_chip_ident, &chip); + v4l2_device_call_all(v4l2_dev, 0, core, g_std, &norm); Any subdev that does not support this ops is skipped and error results are ignored. If you want to check for errors use this: - err = v4l2_device_call_until_err(v4l2_dev, 0, core, g_chip_ident, &chip); + err = v4l2_device_call_until_err(v4l2_dev, 0, core, g_std, &norm); Any error except -ENOIOCTLCMD will exit the loop with that error. If no errors (except -ENOIOCTLCMD) occurred, then 0 is returned. diff --git a/Documentation/zh_CN/video4linux/v4l2-framework.txt b/Documentation/zh_CN/video4linux/v4l2-framework.txt index 44c1d934c4e..0da95dbaef3 100644 --- a/Documentation/zh_CN/video4linux/v4l2-framework.txt +++ b/Documentation/zh_CN/video4linux/v4l2-framework.txt @@ -247,7 +247,6 @@ i2c_client 结构体，i2c_set_clientdata() 函数可用于保存一个 v4l2_sub 这些结构体定义如下： struct v4l2_subdev_core_ops { - int (*g_chip_ident)(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip); int (*log_status)(struct v4l2_subdev *sd); int (*init)(struct v4l2_subdev *sd, u32 val); ... @@ -337,24 +336,24 @@ subdev->dev 域就指向了 v4l2_device。 注册之设备后，可通过以下方式直接调用其操作函数： - err = sd->ops->core->g_chip_ident(sd, &chip); + err = sd->ops->core->g_std(sd, &norm); 但使用如下宏会比较容易且合适： - err = v4l2_subdev_call(sd, core, g_chip_ident, &chip); + err = v4l2_subdev_call(sd, core, g_std, &norm); 这个宏将会做 NULL 指针检查，如果 subdev 为 NULL，则返回-ENODEV；如果 -subdev->core 或 subdev->core->g_chip_ident 为 NULL，则返回 -ENOIOCTLCMD； -否则将返回 subdev->ops->core->g_chip_ident ops 调用的实际结果。 +subdev->core 或 subdev->core->g_std 为 NULL，则返回 -ENOIOCTLCMD； +否则将返回 subdev->ops->core->g_std ops 调用的实际结果。 有时也可能同时调用所有或一系列子设备的某个操作函数： - v4l2_device_call_all(v4l2_dev, 0, core, g_chip_ident, &chip); + v4l2_device_call_all(v4l2_dev, 0, core, g_std, &norm); 任何不支持此操作的子设备都会被跳过，并忽略错误返回值。但如果你需要 检查出错码，则可使用如下函数： - err = v4l2_device_call_until_err(v4l2_dev, 0, core, g_chip_ident, &chip); + err = v4l2_device_call_until_err(v4l2_dev, 0, core, g_std, &norm); 除 -ENOIOCTLCMD 外的任何错误都会跳出循环并返回错误值。如果（除 -ENOIOCTLCMD 外）没有错误发生，则返回 0。 |