[media] v4l2-ctrls: add a filter function to v4l2_ctrl_add_handler

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / Documentation / video4linux / v4l2-controls.txt

diff --git a/Documentation/video4linux/v4l2-controls.txt b/Documentation/video4linux/v4l2-controls.txt
index 43da22b8972869c7d283d751674d6633d7cd822d..54270df99d5c2f1794c4fcd537eec05fd525d031 100644 (file)
--- a/Documentation/video4linux/v4l2-controls.txt
+++ b/Documentation/video4linux/v4l2-controls.txt
@@ -594,7 +594,11 @@ handler and finally add the first handler to the second. For example:
        v4l2_ctrl_new_std(&radio_ctrl_handler, &radio_ops, V4L2_CID_AUDIO_MUTE, ...);
        v4l2_ctrl_new_std(&video_ctrl_handler, &video_ops, V4L2_CID_BRIGHTNESS, ...);
        v4l2_ctrl_new_std(&video_ctrl_handler, &video_ops, V4L2_CID_CONTRAST, ...);
-       v4l2_ctrl_add_handler(&video_ctrl_handler, &radio_ctrl_handler);
+       v4l2_ctrl_add_handler(&video_ctrl_handler, &radio_ctrl_handler, NULL);
+
+The last argument to v4l2_ctrl_add_handler() is a filter function that allows
+you to filter which controls will be added. Set it to NULL if you want to add
+all controls.
 
 Or you can add specific controls to a handler: