The code snippet showing how to add controls to the driver’s top-level
struct is present twice, but only the second time it is split in the V4L2
and subdev cases. Consolidate everything at the beginning.
Also remove the "Where foo->bar is of type struct baz" sentences, this
obvious from the code.
Signed-off-by: Luca Ceresoli <luca@xxxxxxxxxxxxxxxx>
---
Documentation/media/kapi/v4l2-controls.rst | 40 +++++++++-------------
1 file changed, 17 insertions(+), 23 deletions(-)
diff --git a/Documentation/media/kapi/v4l2-controls.rst b/Documentation/media/kapi/v4l2-controls.rst
index 0c3f486727ed..5281c9b1fd66 100644
--- a/Documentation/media/kapi/v4l2-controls.rst
+++ b/Documentation/media/kapi/v4l2-controls.rst
@@ -52,15 +52,29 @@ Basic usage for V4L2 and sub-device drivers
1.1) Add the handler to your driver's top-level struct:
+For V4L2 drivers:
+
.. code-block:: none
struct foo_dev {
+ ...
+ struct v4l2_device v4l2_dev;
...
struct v4l2_ctrl_handler ctrl_handler;
...
};
- struct foo_dev *foo;
+For sub-device drivers:
+
+.. code-block:: none
+
+ struct foo_dev {
+ ...
+ struct v4l2_subdev sd;
+ ...
+ struct v4l2_ctrl_handler ctrl_handler;
+ ...
+ };
1.2) Initialize the handler:
@@ -74,43 +88,23 @@ information. It is a hint only.
1.3) Hook the control handler into the driver:
-1.3.1) For V4L2 drivers do this:
+For V4L2 drivers:
.. code-block:: none
- struct foo_dev {
- ...
- struct v4l2_device v4l2_dev;
- ...
- struct v4l2_ctrl_handler ctrl_handler;
- ...
- };
-
foo->v4l2_dev.ctrl_handler = &foo->ctrl_handler;
-Where foo->v4l2_dev is of type struct v4l2_device.
-
Finally, remove all control functions from your v4l2_ioctl_ops (if any):
vidioc_queryctrl, vidioc_query_ext_ctrl, vidioc_querymenu, vidioc_g_ctrl,
vidioc_s_ctrl, vidioc_g_ext_ctrls, vidioc_try_ext_ctrls and vidioc_s_ext_ctrls.
Those are now no longer needed.
-1.3.2) For sub-device drivers do this:
+For sub-device drivers:
.. code-block:: none
- struct foo_dev {
- ...
- struct v4l2_subdev sd;
- ...
- struct v4l2_ctrl_handler ctrl_handler;
- ...
- };
-
foo->sd.ctrl_handler = &foo->ctrl_handler;
-Where foo->sd is of type struct v4l2_subdev.
-
1.4) Clean up the handler at the end:
.. code-block:: none
--
2.21.0
