On 01/23/2014 02:46 PM, Sylwester Nawrocki wrote: > On 20/01/14 13:46, Hans Verkuil wrote: >> From: Hans Verkuil <hans.verkuil@xxxxxxxxx> >> >> Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx> >> --- >> .../DocBook/media/v4l/vidioc-g-ext-ctrls.xml | 43 ++++++++++++++++++---- >> 1 file changed, 35 insertions(+), 8 deletions(-) >> >> diff --git a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml >> index b3bb957..bb383b9 100644 >> --- a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml >> +++ b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml >> @@ -72,23 +72,30 @@ initialize the <structfield>id</structfield>, >> <structfield>size</structfield> and <structfield>reserved2</structfield> fields >> of each &v4l2-ext-control; and call the >> <constant>VIDIOC_G_EXT_CTRLS</constant> ioctl. String controls controls >> -must also set the <structfield>string</structfield> field.</para> >> +must also set the <structfield>string</structfield> field. Controls >> +of complex types (<constant>V4L2_CTRL_FLAG_IS_PTR</constant> is set) >> +must set the <structfield>p</structfield> field.</para> >> >> <para>If the <structfield>size</structfield> is too small to >> receive the control result (only relevant for pointer-type controls >> like strings), then the driver will set <structfield>size</structfield> >> to a valid value and return an &ENOSPC;. You should re-allocate the >> -string memory to this new size and try again. It is possible that the >> -same issue occurs again if the string has grown in the meantime. It is >> +memory to this new size and try again. For the string type it is possible that >> +the same issue occurs again if the string has grown in the meantime. It is >> recommended to call &VIDIOC-QUERYCTRL; first and use >> <structfield>maximum</structfield>+1 as the new <structfield>size</structfield> >> value. It is guaranteed that that is sufficient memory. >> </para> >> >> + <para>For matrices it is possible to only get the first <constant>X</constant> >> +elements by setting size to <constant>X * elem_size</constant>, where >> +<structfield>elem_size</structfield> is obtained by calling &VIDIOC-QUERY-EXT-CTRL;. >> +Matrix elements are returned row-by-row.</para> >> + >> <para>To change the value of a set of controls applications >> initialize the <structfield>id</structfield>, <structfield>size</structfield>, >> <structfield>reserved2</structfield> and >> -<structfield>value/string</structfield> fields of each &v4l2-ext-control; and >> +<structfield>value/value64/string/p</structfield> fields of each &v4l2-ext-control; and >> call the <constant>VIDIOC_S_EXT_CTRLS</constant> ioctl. The controls >> will only be set if <emphasis>all</emphasis> control values are >> valid.</para> >> @@ -96,11 +103,17 @@ valid.</para> >> <para>To check if a set of controls have correct values applications >> initialize the <structfield>id</structfield>, <structfield>size</structfield>, >> <structfield>reserved2</structfield> and >> -<structfield>value/string</structfield> fields of each &v4l2-ext-control; and >> +<structfield>value/value64/string/p</structfield> fields of each &v4l2-ext-control; and >> call the <constant>VIDIOC_TRY_EXT_CTRLS</constant> ioctl. It is up to >> the driver whether wrong values are automatically adjusted to a valid >> value or if an error is returned.</para> >> >> + <para>For matrices it is possible to only set or check only the first >> +<constant>X</constant> elements by setting size to <constant>X * elem_size</constant>, >> +where <structfield>elem_size</structfield> is obtained by calling &VIDIOC-QUERY-EXT-CTRL;. >> +Matrix elements are set row-by-row. Matrix elements that are not explicitly >> +set will be initialized to their default value.</para> > > Presumably this could be more problematic than leaving the remaining part > of the matrix unchanged. I assume this paragraph is going to be removed ? Yes, that's going away. Regards, Hans > >> <para>When the <structfield>id</structfield> or >> <structfield>ctrl_class</structfield> is invalid drivers return an >> &EINVAL;. When the value is out of bounds drivers can choose to take >> @@ -158,19 +171,33 @@ applications must set the array to zero.</entry> >> <entry></entry> >> <entry>__s32</entry> >> <entry><structfield>value</structfield></entry> >> - <entry>New value or current value.</entry> >> + <entry>New value or current value. Valid if this control is not of >> +type <constant>V4L2_CTRL_TYPE_INTEGER64</constant> and >> +<constant>V4L2_CTRL_FLAG_IS_PTR</constant> is not set.</entry> >> </row> >> <row> >> <entry></entry> >> <entry>__s64</entry> >> <entry><structfield>value64</structfield></entry> >> - <entry>New value or current value.</entry> >> + <entry>New value or current value. Valid if this control is of >> +type <constant>V4L2_CTRL_TYPE_INTEGER64</constant> and >> +<constant>V4L2_CTRL_FLAG_IS_PTR</constant> is not set.</entry> >> </row> >> <row> >> <entry></entry> >> <entry>char *</entry> >> <entry><structfield>string</structfield></entry> >> - <entry>A pointer to a string.</entry> >> + <entry>A pointer to a string. Valid if this control is of >> +type <constant>V4L2_CTRL_TYPE_STRING</constant>.</entry> >> + </row> >> + <row> >> + <entry></entry> >> + <entry>void *</entry> >> + <entry><structfield>p</structfield></entry> >> + <entry>A pointer to a complex type which can be a matrix and/or a >> +complex type (the control's type is >= <constant>V4L2_CTRL_COMPLEX_TYPES</constant>). >> +Valid if <constant>V4L2_CTRL_FLAG_IS_PTR</constant> is set for this control. >> +</entry> >> </row> >> </tbody> >> </tgroup> > > -- > Regards, > Sylwester > -- 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
