From e36160b84253d7125d0fa4109a3d69f0c55fc5d0 Mon Sep 17 00:00:00 2001 From: Luca Ceresoli Date: Thu, 13 Jun 2019 10:18:22 -0400 Subject: [PATCH] media: docs: v4l2-controls: rearrange control initialization sequence MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- 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 -- 2.30.2