On 08/21/2015 11:29 AM, Ricardo Ribalda Delgado wrote: > Vidioc-g-ext-ctrls can now be used to get the default value of the > controls. > > Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@xxxxxxxxx> > --- > Documentation/DocBook/media/v4l/v4l2.xml | 9 +++++++++ > Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml | 14 ++++++++++++++ > 2 files changed, 23 insertions(+) > > diff --git a/Documentation/DocBook/media/v4l/v4l2.xml b/Documentation/DocBook/media/v4l/v4l2.xml > index e98caa1c39bd..be52bd2fb335 100644 > --- a/Documentation/DocBook/media/v4l/v4l2.xml > +++ b/Documentation/DocBook/media/v4l/v4l2.xml > @@ -153,6 +153,15 @@ structs, ioctls) must be noted in more detail in the history chapter > applications. --> > > <revision> > + <revnumber>4.4</revnumber> > + <date>2015-08-20</date> > + <authorinitials>rr</authorinitials> > + <revremark>Extend vidioc-g-ext-ctrls;. Replace ctrl_class with a new > +union with ctrl_class and which. Which is used to select the current value of > +the control or the default value. > + </revremark> > + </revision> > + <revision> > <revnumber>3.21</revnumber> > <date>2015-02-13</date> > <authorinitials>mcc</authorinitials> > diff --git a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml > index c5bdbfcc42b3..224fa2bd1481 100644 > --- a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml > +++ b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml > @@ -216,7 +216,12 @@ Valid if <constant>V4L2_CTRL_FLAG_HAS_PAYLOAD</constant> is set for this control > <tgroup cols="3"> > &cs-str; > <tbody valign="top"> > + <row> > + <entry>union</entry> > + <entry>(anonymous)</entry> > + </row> > <row> > + <entry></entry> > <entry>__u32</entry> > <entry><structfield>ctrl_class</structfield></entry> > <entry>The control class to which all controls belong, see > @@ -228,6 +233,15 @@ with a <structfield>count</structfield> of 0. If that succeeds, then the driver > supports this feature.</entry> All I would say here is that ctrl_class is an alias for 'which', kept for backwards compatibility. Applications should use 'which' instead. > </row> > <row> > + <entry></entry> > + <entry>__u32</entry> > + <entry><structfield>which</structfield></entry> > + <entry> Which control are get/set/tried. <constant>V4L2_CTRL_WHICH_CUR_VAL</constant> I'd say: "Which value of the control to get/set/try." > +will return the current value of the control and <constant>V4L2_CTRL_WHICH_DEF_VAL</constant> will > +return the default value of the control. Please note that the default value of the control cannot > +be set or tried, only get.</entry> I'd rephrase that: "Please note that you can only get the default value of the control, you cannot set or try it." Add this: "For backwards compatibility you can also use a control class here (see <xref linkend="ctrl-class" />. In that case all controls have to belong to that control class. This usage is deprecated, instead just use <constant>V4L2_CTRL_WHICH_CUR_VAL</constant>. There are some very old drivers that do not yet support <constant>V4L2_CTRL_WHICH_CUR_VAL</constant> and that require a control class here. You can test for such drivers by setting ctrl_class to <constant>V4L2_CTRL_WHICH_CUR_VAL</constant> and calling VIDIOC_TRY_EXT_CTRLS with a count of 0. If that fails, then the driver does not support <constant>V4L2_CTRL_WHICH_CUR_VAL</constant>." I think the only driver that still doesn't support this is saa7164. I really need to convert it to the control framework. Regards, Hans > + </row> > + <row> > <entry>__u32</entry> > <entry><structfield>count</structfield></entry> > <entry>The number of controls in the controls array. May > -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
