diff options
Diffstat (limited to 'v4l2-spec/vidioc-queryctrl.sgml')
| -rw-r--r-- | v4l2-spec/vidioc-queryctrl.sgml | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/v4l2-spec/vidioc-queryctrl.sgml b/v4l2-spec/vidioc-queryctrl.sgml index 20c4147eb..9908a964d 100644 --- a/v4l2-spec/vidioc-queryctrl.sgml +++ b/v4l2-spec/vidioc-queryctrl.sgml @@ -361,6 +361,15 @@ control.</entry> <entry>A hint that this control is best represented as a slider-like element in a user interface.</entry> </row> + <row> + <entry><constant>V4L2_CTRL_FLAG_WRITE_ONLY</constant></entry> + <entry>0x0040</entry> + <entry>This control is permanently writable only. Any +attempt to read the control will result in an &EACCES; error code. This +flag is typically present for relative controls or action controls where +writing a value will cause the device to carry out a given action +(⪚ motor control) but no meaningful value can be returned.</entry> + </row> </tbody> </tgroup> </table> @@ -378,6 +387,12 @@ is invalid. The &v4l2-querymenu; <structfield>id</structfield> or <structfield>index</structfield> is invalid.</para> </listitem> </varlistentry> + <varlistentry> + <term><errorcode>EACCES</errorcode></term> + <listitem> + <para>An attempt was made to read a write-only control.</para> + </listitem> + </varlistentry> </variablelist> </refsect1> </refentry> |